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53e872681f
We cannot wait for transaction commit in journal_unmap_buffer() because we hold page lock which ranks below transaction start. We solve the issue by bailing out of journal_unmap_buffer() and jbd2_journal_invalidatepage() with -EBUSY. Caller is then responsible for waiting for transaction commit to finish and try invalidation again. Since the issue can happen only for page stradding i_size, it is simple enough to manually call jbd2_journal_invalidatepage() for such page from ext4_setattr(), check the return value and wait if necessary. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
5008 lines
144 KiB
C
5008 lines
144 KiB
C
/*
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* linux/fs/ext4/inode.c
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*
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* Copyright (C) 1992, 1993, 1994, 1995
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* Remy Card (card@masi.ibp.fr)
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* Laboratoire MASI - Institut Blaise Pascal
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* Universite Pierre et Marie Curie (Paris VI)
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*
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* from
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*
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* linux/fs/minix/inode.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* 64-bit file support on 64-bit platforms by Jakub Jelinek
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* (jj@sunsite.ms.mff.cuni.cz)
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*
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* Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
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*/
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#include <linux/fs.h>
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#include <linux/time.h>
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#include <linux/jbd2.h>
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#include <linux/highuid.h>
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#include <linux/pagemap.h>
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#include <linux/quotaops.h>
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#include <linux/string.h>
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#include <linux/buffer_head.h>
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#include <linux/writeback.h>
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#include <linux/pagevec.h>
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#include <linux/mpage.h>
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#include <linux/namei.h>
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#include <linux/uio.h>
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#include <linux/bio.h>
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#include <linux/workqueue.h>
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#include <linux/kernel.h>
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#include <linux/printk.h>
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#include <linux/slab.h>
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#include <linux/ratelimit.h>
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#include "ext4_jbd2.h"
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#include "xattr.h"
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#include "acl.h"
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#include "truncate.h"
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#include <trace/events/ext4.h>
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#define MPAGE_DA_EXTENT_TAIL 0x01
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static __u32 ext4_inode_csum(struct inode *inode, struct ext4_inode *raw,
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struct ext4_inode_info *ei)
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{
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struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
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__u16 csum_lo;
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__u16 csum_hi = 0;
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__u32 csum;
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csum_lo = raw->i_checksum_lo;
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raw->i_checksum_lo = 0;
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if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
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EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi)) {
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csum_hi = raw->i_checksum_hi;
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raw->i_checksum_hi = 0;
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}
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csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)raw,
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EXT4_INODE_SIZE(inode->i_sb));
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raw->i_checksum_lo = csum_lo;
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if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
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EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
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raw->i_checksum_hi = csum_hi;
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return csum;
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}
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static int ext4_inode_csum_verify(struct inode *inode, struct ext4_inode *raw,
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struct ext4_inode_info *ei)
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{
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__u32 provided, calculated;
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if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
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cpu_to_le32(EXT4_OS_LINUX) ||
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!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
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EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
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return 1;
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provided = le16_to_cpu(raw->i_checksum_lo);
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calculated = ext4_inode_csum(inode, raw, ei);
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if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
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EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
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provided |= ((__u32)le16_to_cpu(raw->i_checksum_hi)) << 16;
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else
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calculated &= 0xFFFF;
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return provided == calculated;
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}
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static void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
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struct ext4_inode_info *ei)
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{
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__u32 csum;
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if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
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cpu_to_le32(EXT4_OS_LINUX) ||
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!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
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EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
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return;
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csum = ext4_inode_csum(inode, raw, ei);
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raw->i_checksum_lo = cpu_to_le16(csum & 0xFFFF);
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if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
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EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
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raw->i_checksum_hi = cpu_to_le16(csum >> 16);
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}
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static inline int ext4_begin_ordered_truncate(struct inode *inode,
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loff_t new_size)
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{
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trace_ext4_begin_ordered_truncate(inode, new_size);
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/*
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* If jinode is zero, then we never opened the file for
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* writing, so there's no need to call
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* jbd2_journal_begin_ordered_truncate() since there's no
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* outstanding writes we need to flush.
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*/
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if (!EXT4_I(inode)->jinode)
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return 0;
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return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode),
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EXT4_I(inode)->jinode,
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new_size);
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}
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static void ext4_invalidatepage(struct page *page, unsigned long offset);
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static int noalloc_get_block_write(struct inode *inode, sector_t iblock,
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struct buffer_head *bh_result, int create);
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static int ext4_set_bh_endio(struct buffer_head *bh, struct inode *inode);
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static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate);
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static int __ext4_journalled_writepage(struct page *page, unsigned int len);
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static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh);
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static int ext4_discard_partial_page_buffers_no_lock(handle_t *handle,
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struct inode *inode, struct page *page, loff_t from,
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loff_t length, int flags);
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/*
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* Test whether an inode is a fast symlink.
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*/
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static int ext4_inode_is_fast_symlink(struct inode *inode)
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{
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int ea_blocks = EXT4_I(inode)->i_file_acl ?
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(inode->i_sb->s_blocksize >> 9) : 0;
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return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
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}
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/*
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* Restart the transaction associated with *handle. This does a commit,
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* so before we call here everything must be consistently dirtied against
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* this transaction.
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*/
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int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode,
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int nblocks)
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{
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int ret;
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/*
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* Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
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* moment, get_block can be called only for blocks inside i_size since
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* page cache has been already dropped and writes are blocked by
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* i_mutex. So we can safely drop the i_data_sem here.
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*/
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BUG_ON(EXT4_JOURNAL(inode) == NULL);
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jbd_debug(2, "restarting handle %p\n", handle);
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up_write(&EXT4_I(inode)->i_data_sem);
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ret = ext4_journal_restart(handle, nblocks);
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down_write(&EXT4_I(inode)->i_data_sem);
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ext4_discard_preallocations(inode);
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return ret;
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}
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/*
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* Called at the last iput() if i_nlink is zero.
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*/
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void ext4_evict_inode(struct inode *inode)
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{
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handle_t *handle;
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int err;
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trace_ext4_evict_inode(inode);
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ext4_ioend_wait(inode);
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if (inode->i_nlink) {
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/*
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* When journalling data dirty buffers are tracked only in the
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* journal. So although mm thinks everything is clean and
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* ready for reaping the inode might still have some pages to
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* write in the running transaction or waiting to be
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* checkpointed. Thus calling jbd2_journal_invalidatepage()
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* (via truncate_inode_pages()) to discard these buffers can
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* cause data loss. Also even if we did not discard these
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* buffers, we would have no way to find them after the inode
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* is reaped and thus user could see stale data if he tries to
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* read them before the transaction is checkpointed. So be
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* careful and force everything to disk here... We use
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* ei->i_datasync_tid to store the newest transaction
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* containing inode's data.
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*
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* Note that directories do not have this problem because they
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* don't use page cache.
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*/
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if (ext4_should_journal_data(inode) &&
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(S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode))) {
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journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
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tid_t commit_tid = EXT4_I(inode)->i_datasync_tid;
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jbd2_log_start_commit(journal, commit_tid);
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jbd2_log_wait_commit(journal, commit_tid);
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filemap_write_and_wait(&inode->i_data);
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}
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truncate_inode_pages(&inode->i_data, 0);
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goto no_delete;
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}
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if (!is_bad_inode(inode))
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dquot_initialize(inode);
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if (ext4_should_order_data(inode))
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ext4_begin_ordered_truncate(inode, 0);
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truncate_inode_pages(&inode->i_data, 0);
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if (is_bad_inode(inode))
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goto no_delete;
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/*
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* Protect us against freezing - iput() caller didn't have to have any
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* protection against it
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*/
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sb_start_intwrite(inode->i_sb);
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handle = ext4_journal_start(inode, ext4_blocks_for_truncate(inode)+3);
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if (IS_ERR(handle)) {
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ext4_std_error(inode->i_sb, PTR_ERR(handle));
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/*
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* If we're going to skip the normal cleanup, we still need to
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* make sure that the in-core orphan linked list is properly
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* cleaned up.
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*/
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ext4_orphan_del(NULL, inode);
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sb_end_intwrite(inode->i_sb);
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goto no_delete;
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}
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if (IS_SYNC(inode))
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ext4_handle_sync(handle);
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inode->i_size = 0;
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err = ext4_mark_inode_dirty(handle, inode);
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if (err) {
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ext4_warning(inode->i_sb,
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"couldn't mark inode dirty (err %d)", err);
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goto stop_handle;
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}
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if (inode->i_blocks)
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ext4_truncate(inode);
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/*
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* ext4_ext_truncate() doesn't reserve any slop when it
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* restarts journal transactions; therefore there may not be
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* enough credits left in the handle to remove the inode from
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* the orphan list and set the dtime field.
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*/
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if (!ext4_handle_has_enough_credits(handle, 3)) {
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err = ext4_journal_extend(handle, 3);
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if (err > 0)
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err = ext4_journal_restart(handle, 3);
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if (err != 0) {
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ext4_warning(inode->i_sb,
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"couldn't extend journal (err %d)", err);
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stop_handle:
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ext4_journal_stop(handle);
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ext4_orphan_del(NULL, inode);
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sb_end_intwrite(inode->i_sb);
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goto no_delete;
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}
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}
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/*
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* Kill off the orphan record which ext4_truncate created.
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* AKPM: I think this can be inside the above `if'.
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* Note that ext4_orphan_del() has to be able to cope with the
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* deletion of a non-existent orphan - this is because we don't
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* know if ext4_truncate() actually created an orphan record.
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* (Well, we could do this if we need to, but heck - it works)
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*/
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ext4_orphan_del(handle, inode);
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EXT4_I(inode)->i_dtime = get_seconds();
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/*
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* One subtle ordering requirement: if anything has gone wrong
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* (transaction abort, IO errors, whatever), then we can still
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* do these next steps (the fs will already have been marked as
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* having errors), but we can't free the inode if the mark_dirty
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* fails.
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*/
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if (ext4_mark_inode_dirty(handle, inode))
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/* If that failed, just do the required in-core inode clear. */
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ext4_clear_inode(inode);
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else
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ext4_free_inode(handle, inode);
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ext4_journal_stop(handle);
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sb_end_intwrite(inode->i_sb);
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return;
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no_delete:
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ext4_clear_inode(inode); /* We must guarantee clearing of inode... */
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}
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#ifdef CONFIG_QUOTA
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qsize_t *ext4_get_reserved_space(struct inode *inode)
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{
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return &EXT4_I(inode)->i_reserved_quota;
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}
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#endif
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/*
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* Calculate the number of metadata blocks need to reserve
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* to allocate a block located at @lblock
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*/
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static int ext4_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
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{
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if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
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return ext4_ext_calc_metadata_amount(inode, lblock);
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return ext4_ind_calc_metadata_amount(inode, lblock);
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}
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/*
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* Called with i_data_sem down, which is important since we can call
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* ext4_discard_preallocations() from here.
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*/
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void ext4_da_update_reserve_space(struct inode *inode,
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int used, int quota_claim)
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{
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struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
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struct ext4_inode_info *ei = EXT4_I(inode);
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spin_lock(&ei->i_block_reservation_lock);
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trace_ext4_da_update_reserve_space(inode, used, quota_claim);
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if (unlikely(used > ei->i_reserved_data_blocks)) {
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ext4_msg(inode->i_sb, KERN_NOTICE, "%s: ino %lu, used %d "
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"with only %d reserved data blocks",
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__func__, inode->i_ino, used,
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ei->i_reserved_data_blocks);
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WARN_ON(1);
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used = ei->i_reserved_data_blocks;
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}
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if (unlikely(ei->i_allocated_meta_blocks > ei->i_reserved_meta_blocks)) {
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ext4_msg(inode->i_sb, KERN_NOTICE, "%s: ino %lu, allocated %d "
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"with only %d reserved metadata blocks\n", __func__,
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inode->i_ino, ei->i_allocated_meta_blocks,
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ei->i_reserved_meta_blocks);
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WARN_ON(1);
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ei->i_allocated_meta_blocks = ei->i_reserved_meta_blocks;
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}
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|
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/* Update per-inode reservations */
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ei->i_reserved_data_blocks -= used;
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ei->i_reserved_meta_blocks -= ei->i_allocated_meta_blocks;
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percpu_counter_sub(&sbi->s_dirtyclusters_counter,
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used + ei->i_allocated_meta_blocks);
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ei->i_allocated_meta_blocks = 0;
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|
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if (ei->i_reserved_data_blocks == 0) {
|
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/*
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* We can release all of the reserved metadata blocks
|
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* only when we have written all of the delayed
|
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* allocation blocks.
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*/
|
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percpu_counter_sub(&sbi->s_dirtyclusters_counter,
|
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ei->i_reserved_meta_blocks);
|
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ei->i_reserved_meta_blocks = 0;
|
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ei->i_da_metadata_calc_len = 0;
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}
|
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spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
|
|
|
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/* Update quota subsystem for data blocks */
|
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if (quota_claim)
|
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dquot_claim_block(inode, EXT4_C2B(sbi, used));
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else {
|
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/*
|
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* We did fallocate with an offset that is already delayed
|
|
* allocated. So on delayed allocated writeback we should
|
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* not re-claim the quota for fallocated blocks.
|
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*/
|
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dquot_release_reservation_block(inode, EXT4_C2B(sbi, used));
|
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}
|
|
|
|
/*
|
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* If we have done all the pending block allocations and if
|
|
* there aren't any writers on the inode, we can discard the
|
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* inode's preallocations.
|
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*/
|
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if ((ei->i_reserved_data_blocks == 0) &&
|
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(atomic_read(&inode->i_writecount) == 0))
|
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ext4_discard_preallocations(inode);
|
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}
|
|
|
|
static int __check_block_validity(struct inode *inode, const char *func,
|
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unsigned int line,
|
|
struct ext4_map_blocks *map)
|
|
{
|
|
if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), map->m_pblk,
|
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map->m_len)) {
|
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ext4_error_inode(inode, func, line, map->m_pblk,
|
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"lblock %lu mapped to illegal pblock "
|
|
"(length %d)", (unsigned long) map->m_lblk,
|
|
map->m_len);
|
|
return -EIO;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#define check_block_validity(inode, map) \
|
|
__check_block_validity((inode), __func__, __LINE__, (map))
|
|
|
|
/*
|
|
* Return the number of contiguous dirty pages in a given inode
|
|
* starting at page frame idx.
|
|
*/
|
|
static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
|
|
unsigned int max_pages)
|
|
{
|
|
struct address_space *mapping = inode->i_mapping;
|
|
pgoff_t index;
|
|
struct pagevec pvec;
|
|
pgoff_t num = 0;
|
|
int i, nr_pages, done = 0;
|
|
|
|
if (max_pages == 0)
|
|
return 0;
|
|
pagevec_init(&pvec, 0);
|
|
while (!done) {
|
|
index = idx;
|
|
nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
|
|
PAGECACHE_TAG_DIRTY,
|
|
(pgoff_t)PAGEVEC_SIZE);
|
|
if (nr_pages == 0)
|
|
break;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec.pages[i];
|
|
struct buffer_head *bh, *head;
|
|
|
|
lock_page(page);
|
|
if (unlikely(page->mapping != mapping) ||
|
|
!PageDirty(page) ||
|
|
PageWriteback(page) ||
|
|
page->index != idx) {
|
|
done = 1;
|
|
unlock_page(page);
|
|
break;
|
|
}
|
|
if (page_has_buffers(page)) {
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (!buffer_delay(bh) &&
|
|
!buffer_unwritten(bh))
|
|
done = 1;
|
|
bh = bh->b_this_page;
|
|
} while (!done && (bh != head));
|
|
}
|
|
unlock_page(page);
|
|
if (done)
|
|
break;
|
|
idx++;
|
|
num++;
|
|
if (num >= max_pages) {
|
|
done = 1;
|
|
break;
|
|
}
|
|
}
|
|
pagevec_release(&pvec);
|
|
}
|
|
return num;
|
|
}
|
|
|
|
/*
|
|
* The ext4_map_blocks() function tries to look up the requested blocks,
|
|
* and returns if the blocks are already mapped.
|
|
*
|
|
* Otherwise it takes the write lock of the i_data_sem and allocate blocks
|
|
* and store the allocated blocks in the result buffer head and mark it
|
|
* mapped.
|
|
*
|
|
* If file type is extents based, it will call ext4_ext_map_blocks(),
|
|
* Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
|
|
* based files
|
|
*
|
|
* On success, it returns the number of blocks being mapped or allocate.
|
|
* if create==0 and the blocks are pre-allocated and uninitialized block,
|
|
* the result buffer head is unmapped. If the create ==1, it will make sure
|
|
* the buffer head is mapped.
|
|
*
|
|
* It returns 0 if plain look up failed (blocks have not been allocated), in
|
|
* that case, buffer head is unmapped
|
|
*
|
|
* It returns the error in case of allocation failure.
|
|
*/
|
|
int ext4_map_blocks(handle_t *handle, struct inode *inode,
|
|
struct ext4_map_blocks *map, int flags)
|
|
{
|
|
int retval;
|
|
|
|
map->m_flags = 0;
|
|
ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
|
|
"logical block %lu\n", inode->i_ino, flags, map->m_len,
|
|
(unsigned long) map->m_lblk);
|
|
/*
|
|
* Try to see if we can get the block without requesting a new
|
|
* file system block.
|
|
*/
|
|
if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
|
|
down_read((&EXT4_I(inode)->i_data_sem));
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
retval = ext4_ext_map_blocks(handle, inode, map, flags &
|
|
EXT4_GET_BLOCKS_KEEP_SIZE);
|
|
} else {
|
|
retval = ext4_ind_map_blocks(handle, inode, map, flags &
|
|
EXT4_GET_BLOCKS_KEEP_SIZE);
|
|
}
|
|
if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
|
|
up_read((&EXT4_I(inode)->i_data_sem));
|
|
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
|
|
int ret;
|
|
if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
|
|
/* delayed alloc may be allocated by fallocate and
|
|
* coverted to initialized by directIO.
|
|
* we need to handle delayed extent here.
|
|
*/
|
|
down_write((&EXT4_I(inode)->i_data_sem));
|
|
goto delayed_mapped;
|
|
}
|
|
ret = check_block_validity(inode, map);
|
|
if (ret != 0)
|
|
return ret;
|
|
}
|
|
|
|
/* If it is only a block(s) look up */
|
|
if ((flags & EXT4_GET_BLOCKS_CREATE) == 0)
|
|
return retval;
|
|
|
|
/*
|
|
* Returns if the blocks have already allocated
|
|
*
|
|
* Note that if blocks have been preallocated
|
|
* ext4_ext_get_block() returns the create = 0
|
|
* with buffer head unmapped.
|
|
*/
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED)
|
|
return retval;
|
|
|
|
/*
|
|
* When we call get_blocks without the create flag, the
|
|
* BH_Unwritten flag could have gotten set if the blocks
|
|
* requested were part of a uninitialized extent. We need to
|
|
* clear this flag now that we are committed to convert all or
|
|
* part of the uninitialized extent to be an initialized
|
|
* extent. This is because we need to avoid the combination
|
|
* of BH_Unwritten and BH_Mapped flags being simultaneously
|
|
* set on the buffer_head.
|
|
*/
|
|
map->m_flags &= ~EXT4_MAP_UNWRITTEN;
|
|
|
|
/*
|
|
* New blocks allocate and/or writing to uninitialized extent
|
|
* will possibly result in updating i_data, so we take
|
|
* the write lock of i_data_sem, and call get_blocks()
|
|
* with create == 1 flag.
|
|
*/
|
|
down_write((&EXT4_I(inode)->i_data_sem));
|
|
|
|
/*
|
|
* if the caller is from delayed allocation writeout path
|
|
* we have already reserved fs blocks for allocation
|
|
* let the underlying get_block() function know to
|
|
* avoid double accounting
|
|
*/
|
|
if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
|
|
ext4_set_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED);
|
|
/*
|
|
* We need to check for EXT4 here because migrate
|
|
* could have changed the inode type in between
|
|
*/
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
retval = ext4_ext_map_blocks(handle, inode, map, flags);
|
|
} else {
|
|
retval = ext4_ind_map_blocks(handle, inode, map, flags);
|
|
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_NEW) {
|
|
/*
|
|
* We allocated new blocks which will result in
|
|
* i_data's format changing. Force the migrate
|
|
* to fail by clearing migrate flags
|
|
*/
|
|
ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
|
|
}
|
|
|
|
/*
|
|
* Update reserved blocks/metadata blocks after successful
|
|
* block allocation which had been deferred till now. We don't
|
|
* support fallocate for non extent files. So we can update
|
|
* reserve space here.
|
|
*/
|
|
if ((retval > 0) &&
|
|
(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE))
|
|
ext4_da_update_reserve_space(inode, retval, 1);
|
|
}
|
|
if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) {
|
|
ext4_clear_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED);
|
|
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
|
|
int ret;
|
|
delayed_mapped:
|
|
/* delayed allocation blocks has been allocated */
|
|
ret = ext4_es_remove_extent(inode, map->m_lblk,
|
|
map->m_len);
|
|
if (ret < 0)
|
|
retval = ret;
|
|
}
|
|
}
|
|
|
|
up_write((&EXT4_I(inode)->i_data_sem));
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
|
|
int ret = check_block_validity(inode, map);
|
|
if (ret != 0)
|
|
return ret;
|
|
}
|
|
return retval;
|
|
}
|
|
|
|
/* Maximum number of blocks we map for direct IO at once. */
|
|
#define DIO_MAX_BLOCKS 4096
|
|
|
|
static int _ext4_get_block(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh, int flags)
|
|
{
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
struct ext4_map_blocks map;
|
|
int ret = 0, started = 0;
|
|
int dio_credits;
|
|
|
|
if (ext4_has_inline_data(inode))
|
|
return -ERANGE;
|
|
|
|
map.m_lblk = iblock;
|
|
map.m_len = bh->b_size >> inode->i_blkbits;
|
|
|
|
if (flags && !(flags & EXT4_GET_BLOCKS_NO_LOCK) && !handle) {
|
|
/* Direct IO write... */
|
|
if (map.m_len > DIO_MAX_BLOCKS)
|
|
map.m_len = DIO_MAX_BLOCKS;
|
|
dio_credits = ext4_chunk_trans_blocks(inode, map.m_len);
|
|
handle = ext4_journal_start(inode, dio_credits);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
return ret;
|
|
}
|
|
started = 1;
|
|
}
|
|
|
|
ret = ext4_map_blocks(handle, inode, &map, flags);
|
|
if (ret > 0) {
|
|
map_bh(bh, inode->i_sb, map.m_pblk);
|
|
bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
|
|
bh->b_size = inode->i_sb->s_blocksize * map.m_len;
|
|
ret = 0;
|
|
}
|
|
if (started)
|
|
ext4_journal_stop(handle);
|
|
return ret;
|
|
}
|
|
|
|
int ext4_get_block(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh, int create)
|
|
{
|
|
return _ext4_get_block(inode, iblock, bh,
|
|
create ? EXT4_GET_BLOCKS_CREATE : 0);
|
|
}
|
|
|
|
/*
|
|
* `handle' can be NULL if create is zero
|
|
*/
|
|
struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
|
|
ext4_lblk_t block, int create, int *errp)
|
|
{
|
|
struct ext4_map_blocks map;
|
|
struct buffer_head *bh;
|
|
int fatal = 0, err;
|
|
|
|
J_ASSERT(handle != NULL || create == 0);
|
|
|
|
map.m_lblk = block;
|
|
map.m_len = 1;
|
|
err = ext4_map_blocks(handle, inode, &map,
|
|
create ? EXT4_GET_BLOCKS_CREATE : 0);
|
|
|
|
/* ensure we send some value back into *errp */
|
|
*errp = 0;
|
|
|
|
if (err < 0)
|
|
*errp = err;
|
|
if (err <= 0)
|
|
return NULL;
|
|
|
|
bh = sb_getblk(inode->i_sb, map.m_pblk);
|
|
if (!bh) {
|
|
*errp = -EIO;
|
|
return NULL;
|
|
}
|
|
if (map.m_flags & EXT4_MAP_NEW) {
|
|
J_ASSERT(create != 0);
|
|
J_ASSERT(handle != NULL);
|
|
|
|
/*
|
|
* Now that we do not always journal data, we should
|
|
* keep in mind whether this should always journal the
|
|
* new buffer as metadata. For now, regular file
|
|
* writes use ext4_get_block instead, so it's not a
|
|
* problem.
|
|
*/
|
|
lock_buffer(bh);
|
|
BUFFER_TRACE(bh, "call get_create_access");
|
|
fatal = ext4_journal_get_create_access(handle, bh);
|
|
if (!fatal && !buffer_uptodate(bh)) {
|
|
memset(bh->b_data, 0, inode->i_sb->s_blocksize);
|
|
set_buffer_uptodate(bh);
|
|
}
|
|
unlock_buffer(bh);
|
|
BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
|
|
err = ext4_handle_dirty_metadata(handle, inode, bh);
|
|
if (!fatal)
|
|
fatal = err;
|
|
} else {
|
|
BUFFER_TRACE(bh, "not a new buffer");
|
|
}
|
|
if (fatal) {
|
|
*errp = fatal;
|
|
brelse(bh);
|
|
bh = NULL;
|
|
}
|
|
return bh;
|
|
}
|
|
|
|
struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
|
|
ext4_lblk_t block, int create, int *err)
|
|
{
|
|
struct buffer_head *bh;
|
|
|
|
bh = ext4_getblk(handle, inode, block, create, err);
|
|
if (!bh)
|
|
return bh;
|
|
if (buffer_uptodate(bh))
|
|
return bh;
|
|
ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &bh);
|
|
wait_on_buffer(bh);
|
|
if (buffer_uptodate(bh))
|
|
return bh;
|
|
put_bh(bh);
|
|
*err = -EIO;
|
|
return NULL;
|
|
}
|
|
|
|
int ext4_walk_page_buffers(handle_t *handle,
|
|
struct buffer_head *head,
|
|
unsigned from,
|
|
unsigned to,
|
|
int *partial,
|
|
int (*fn)(handle_t *handle,
|
|
struct buffer_head *bh))
|
|
{
|
|
struct buffer_head *bh;
|
|
unsigned block_start, block_end;
|
|
unsigned blocksize = head->b_size;
|
|
int err, ret = 0;
|
|
struct buffer_head *next;
|
|
|
|
for (bh = head, block_start = 0;
|
|
ret == 0 && (bh != head || !block_start);
|
|
block_start = block_end, bh = next) {
|
|
next = bh->b_this_page;
|
|
block_end = block_start + blocksize;
|
|
if (block_end <= from || block_start >= to) {
|
|
if (partial && !buffer_uptodate(bh))
|
|
*partial = 1;
|
|
continue;
|
|
}
|
|
err = (*fn)(handle, bh);
|
|
if (!ret)
|
|
ret = err;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* To preserve ordering, it is essential that the hole instantiation and
|
|
* the data write be encapsulated in a single transaction. We cannot
|
|
* close off a transaction and start a new one between the ext4_get_block()
|
|
* and the commit_write(). So doing the jbd2_journal_start at the start of
|
|
* prepare_write() is the right place.
|
|
*
|
|
* Also, this function can nest inside ext4_writepage() ->
|
|
* block_write_full_page(). In that case, we *know* that ext4_writepage()
|
|
* has generated enough buffer credits to do the whole page. So we won't
|
|
* block on the journal in that case, which is good, because the caller may
|
|
* be PF_MEMALLOC.
|
|
*
|
|
* By accident, ext4 can be reentered when a transaction is open via
|
|
* quota file writes. If we were to commit the transaction while thus
|
|
* reentered, there can be a deadlock - we would be holding a quota
|
|
* lock, and the commit would never complete if another thread had a
|
|
* transaction open and was blocking on the quota lock - a ranking
|
|
* violation.
|
|
*
|
|
* So what we do is to rely on the fact that jbd2_journal_stop/journal_start
|
|
* will _not_ run commit under these circumstances because handle->h_ref
|
|
* is elevated. We'll still have enough credits for the tiny quotafile
|
|
* write.
|
|
*/
|
|
int do_journal_get_write_access(handle_t *handle,
|
|
struct buffer_head *bh)
|
|
{
|
|
int dirty = buffer_dirty(bh);
|
|
int ret;
|
|
|
|
if (!buffer_mapped(bh) || buffer_freed(bh))
|
|
return 0;
|
|
/*
|
|
* __block_write_begin() could have dirtied some buffers. Clean
|
|
* the dirty bit as jbd2_journal_get_write_access() could complain
|
|
* otherwise about fs integrity issues. Setting of the dirty bit
|
|
* by __block_write_begin() isn't a real problem here as we clear
|
|
* the bit before releasing a page lock and thus writeback cannot
|
|
* ever write the buffer.
|
|
*/
|
|
if (dirty)
|
|
clear_buffer_dirty(bh);
|
|
ret = ext4_journal_get_write_access(handle, bh);
|
|
if (!ret && dirty)
|
|
ret = ext4_handle_dirty_metadata(handle, NULL, bh);
|
|
return ret;
|
|
}
|
|
|
|
static int ext4_get_block_write_nolock(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create);
|
|
static int ext4_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
int ret, needed_blocks;
|
|
handle_t *handle;
|
|
int retries = 0;
|
|
struct page *page;
|
|
pgoff_t index;
|
|
unsigned from, to;
|
|
|
|
trace_ext4_write_begin(inode, pos, len, flags);
|
|
/*
|
|
* Reserve one block more for addition to orphan list in case
|
|
* we allocate blocks but write fails for some reason
|
|
*/
|
|
needed_blocks = ext4_writepage_trans_blocks(inode) + 1;
|
|
index = pos >> PAGE_CACHE_SHIFT;
|
|
from = pos & (PAGE_CACHE_SIZE - 1);
|
|
to = from + len;
|
|
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
|
|
ret = ext4_try_to_write_inline_data(mapping, inode, pos, len,
|
|
flags, pagep);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret == 1) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
retry:
|
|
handle = ext4_journal_start(inode, needed_blocks);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
goto out;
|
|
}
|
|
|
|
/* We cannot recurse into the filesystem as the transaction is already
|
|
* started */
|
|
flags |= AOP_FLAG_NOFS;
|
|
|
|
page = grab_cache_page_write_begin(mapping, index, flags);
|
|
if (!page) {
|
|
ext4_journal_stop(handle);
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
*pagep = page;
|
|
|
|
if (ext4_should_dioread_nolock(inode))
|
|
ret = __block_write_begin(page, pos, len, ext4_get_block_write);
|
|
else
|
|
ret = __block_write_begin(page, pos, len, ext4_get_block);
|
|
|
|
if (!ret && ext4_should_journal_data(inode)) {
|
|
ret = ext4_walk_page_buffers(handle, page_buffers(page),
|
|
from, to, NULL,
|
|
do_journal_get_write_access);
|
|
}
|
|
|
|
if (ret) {
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
/*
|
|
* __block_write_begin may have instantiated a few blocks
|
|
* outside i_size. Trim these off again. Don't need
|
|
* i_size_read because we hold i_mutex.
|
|
*
|
|
* Add inode to orphan list in case we crash before
|
|
* truncate finishes
|
|
*/
|
|
if (pos + len > inode->i_size && ext4_can_truncate(inode))
|
|
ext4_orphan_add(handle, inode);
|
|
|
|
ext4_journal_stop(handle);
|
|
if (pos + len > inode->i_size) {
|
|
ext4_truncate_failed_write(inode);
|
|
/*
|
|
* If truncate failed early the inode might
|
|
* still be on the orphan list; we need to
|
|
* make sure the inode is removed from the
|
|
* orphan list in that case.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
}
|
|
}
|
|
|
|
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
|
|
goto retry;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/* For write_end() in data=journal mode */
|
|
static int write_end_fn(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
if (!buffer_mapped(bh) || buffer_freed(bh))
|
|
return 0;
|
|
set_buffer_uptodate(bh);
|
|
return ext4_handle_dirty_metadata(handle, NULL, bh);
|
|
}
|
|
|
|
static int ext4_generic_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
int i_size_changed = 0;
|
|
struct inode *inode = mapping->host;
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
|
|
if (ext4_has_inline_data(inode))
|
|
copied = ext4_write_inline_data_end(inode, pos, len,
|
|
copied, page);
|
|
else
|
|
copied = block_write_end(file, mapping, pos,
|
|
len, copied, page, fsdata);
|
|
|
|
/*
|
|
* No need to use i_size_read() here, the i_size
|
|
* cannot change under us because we hold i_mutex.
|
|
*
|
|
* But it's important to update i_size while still holding page lock:
|
|
* page writeout could otherwise come in and zero beyond i_size.
|
|
*/
|
|
if (pos + copied > inode->i_size) {
|
|
i_size_write(inode, pos + copied);
|
|
i_size_changed = 1;
|
|
}
|
|
|
|
if (pos + copied > EXT4_I(inode)->i_disksize) {
|
|
/* We need to mark inode dirty even if
|
|
* new_i_size is less that inode->i_size
|
|
* bu greater than i_disksize.(hint delalloc)
|
|
*/
|
|
ext4_update_i_disksize(inode, (pos + copied));
|
|
i_size_changed = 1;
|
|
}
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
|
|
/*
|
|
* Don't mark the inode dirty under page lock. First, it unnecessarily
|
|
* makes the holding time of page lock longer. Second, it forces lock
|
|
* ordering of page lock and transaction start for journaling
|
|
* filesystems.
|
|
*/
|
|
if (i_size_changed)
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
|
|
return copied;
|
|
}
|
|
|
|
/*
|
|
* We need to pick up the new inode size which generic_commit_write gave us
|
|
* `file' can be NULL - eg, when called from page_symlink().
|
|
*
|
|
* ext4 never places buffers on inode->i_mapping->private_list. metadata
|
|
* buffers are managed internally.
|
|
*/
|
|
static int ext4_ordered_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
struct inode *inode = mapping->host;
|
|
int ret = 0, ret2;
|
|
|
|
trace_ext4_ordered_write_end(inode, pos, len, copied);
|
|
ret = ext4_jbd2_file_inode(handle, inode);
|
|
|
|
if (ret == 0) {
|
|
ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
|
|
page, fsdata);
|
|
copied = ret2;
|
|
if (pos + len > inode->i_size && ext4_can_truncate(inode))
|
|
/* if we have allocated more blocks and copied
|
|
* less. We will have blocks allocated outside
|
|
* inode->i_size. So truncate them
|
|
*/
|
|
ext4_orphan_add(handle, inode);
|
|
if (ret2 < 0)
|
|
ret = ret2;
|
|
} else {
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
}
|
|
|
|
ret2 = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = ret2;
|
|
|
|
if (pos + len > inode->i_size) {
|
|
ext4_truncate_failed_write(inode);
|
|
/*
|
|
* If truncate failed early the inode might still be
|
|
* on the orphan list; we need to make sure the inode
|
|
* is removed from the orphan list in that case.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
}
|
|
|
|
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
static int ext4_writeback_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
struct inode *inode = mapping->host;
|
|
int ret = 0, ret2;
|
|
|
|
trace_ext4_writeback_write_end(inode, pos, len, copied);
|
|
ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
|
|
page, fsdata);
|
|
copied = ret2;
|
|
if (pos + len > inode->i_size && ext4_can_truncate(inode))
|
|
/* if we have allocated more blocks and copied
|
|
* less. We will have blocks allocated outside
|
|
* inode->i_size. So truncate them
|
|
*/
|
|
ext4_orphan_add(handle, inode);
|
|
|
|
if (ret2 < 0)
|
|
ret = ret2;
|
|
|
|
ret2 = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = ret2;
|
|
|
|
if (pos + len > inode->i_size) {
|
|
ext4_truncate_failed_write(inode);
|
|
/*
|
|
* If truncate failed early the inode might still be
|
|
* on the orphan list; we need to make sure the inode
|
|
* is removed from the orphan list in that case.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
}
|
|
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
static int ext4_journalled_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
struct inode *inode = mapping->host;
|
|
int ret = 0, ret2;
|
|
int partial = 0;
|
|
unsigned from, to;
|
|
loff_t new_i_size;
|
|
|
|
trace_ext4_journalled_write_end(inode, pos, len, copied);
|
|
from = pos & (PAGE_CACHE_SIZE - 1);
|
|
to = from + len;
|
|
|
|
BUG_ON(!ext4_handle_valid(handle));
|
|
|
|
if (ext4_has_inline_data(inode))
|
|
copied = ext4_write_inline_data_end(inode, pos, len,
|
|
copied, page);
|
|
else {
|
|
if (copied < len) {
|
|
if (!PageUptodate(page))
|
|
copied = 0;
|
|
page_zero_new_buffers(page, from+copied, to);
|
|
}
|
|
|
|
ret = ext4_walk_page_buffers(handle, page_buffers(page), from,
|
|
to, &partial, write_end_fn);
|
|
if (!partial)
|
|
SetPageUptodate(page);
|
|
}
|
|
new_i_size = pos + copied;
|
|
if (new_i_size > inode->i_size)
|
|
i_size_write(inode, pos+copied);
|
|
ext4_set_inode_state(inode, EXT4_STATE_JDATA);
|
|
EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
|
|
if (new_i_size > EXT4_I(inode)->i_disksize) {
|
|
ext4_update_i_disksize(inode, new_i_size);
|
|
ret2 = ext4_mark_inode_dirty(handle, inode);
|
|
if (!ret)
|
|
ret = ret2;
|
|
}
|
|
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
if (pos + len > inode->i_size && ext4_can_truncate(inode))
|
|
/* if we have allocated more blocks and copied
|
|
* less. We will have blocks allocated outside
|
|
* inode->i_size. So truncate them
|
|
*/
|
|
ext4_orphan_add(handle, inode);
|
|
|
|
ret2 = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = ret2;
|
|
if (pos + len > inode->i_size) {
|
|
ext4_truncate_failed_write(inode);
|
|
/*
|
|
* If truncate failed early the inode might still be
|
|
* on the orphan list; we need to make sure the inode
|
|
* is removed from the orphan list in that case.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
}
|
|
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
/*
|
|
* Reserve a single cluster located at lblock
|
|
*/
|
|
static int ext4_da_reserve_space(struct inode *inode, ext4_lblk_t lblock)
|
|
{
|
|
int retries = 0;
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
unsigned int md_needed;
|
|
int ret;
|
|
ext4_lblk_t save_last_lblock;
|
|
int save_len;
|
|
|
|
/*
|
|
* We will charge metadata quota at writeout time; this saves
|
|
* us from metadata over-estimation, though we may go over by
|
|
* a small amount in the end. Here we just reserve for data.
|
|
*/
|
|
ret = dquot_reserve_block(inode, EXT4_C2B(sbi, 1));
|
|
if (ret)
|
|
return ret;
|
|
|
|
/*
|
|
* recalculate the amount of metadata blocks to reserve
|
|
* in order to allocate nrblocks
|
|
* worse case is one extent per block
|
|
*/
|
|
repeat:
|
|
spin_lock(&ei->i_block_reservation_lock);
|
|
/*
|
|
* ext4_calc_metadata_amount() has side effects, which we have
|
|
* to be prepared undo if we fail to claim space.
|
|
*/
|
|
save_len = ei->i_da_metadata_calc_len;
|
|
save_last_lblock = ei->i_da_metadata_calc_last_lblock;
|
|
md_needed = EXT4_NUM_B2C(sbi,
|
|
ext4_calc_metadata_amount(inode, lblock));
|
|
trace_ext4_da_reserve_space(inode, md_needed);
|
|
|
|
/*
|
|
* We do still charge estimated metadata to the sb though;
|
|
* we cannot afford to run out of free blocks.
|
|
*/
|
|
if (ext4_claim_free_clusters(sbi, md_needed + 1, 0)) {
|
|
ei->i_da_metadata_calc_len = save_len;
|
|
ei->i_da_metadata_calc_last_lblock = save_last_lblock;
|
|
spin_unlock(&ei->i_block_reservation_lock);
|
|
if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
|
|
yield();
|
|
goto repeat;
|
|
}
|
|
dquot_release_reservation_block(inode, EXT4_C2B(sbi, 1));
|
|
return -ENOSPC;
|
|
}
|
|
ei->i_reserved_data_blocks++;
|
|
ei->i_reserved_meta_blocks += md_needed;
|
|
spin_unlock(&ei->i_block_reservation_lock);
|
|
|
|
return 0; /* success */
|
|
}
|
|
|
|
static void ext4_da_release_space(struct inode *inode, int to_free)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
|
|
if (!to_free)
|
|
return; /* Nothing to release, exit */
|
|
|
|
spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
|
|
|
|
trace_ext4_da_release_space(inode, to_free);
|
|
if (unlikely(to_free > ei->i_reserved_data_blocks)) {
|
|
/*
|
|
* if there aren't enough reserved blocks, then the
|
|
* counter is messed up somewhere. Since this
|
|
* function is called from invalidate page, it's
|
|
* harmless to return without any action.
|
|
*/
|
|
ext4_msg(inode->i_sb, KERN_NOTICE, "ext4_da_release_space: "
|
|
"ino %lu, to_free %d with only %d reserved "
|
|
"data blocks", inode->i_ino, to_free,
|
|
ei->i_reserved_data_blocks);
|
|
WARN_ON(1);
|
|
to_free = ei->i_reserved_data_blocks;
|
|
}
|
|
ei->i_reserved_data_blocks -= to_free;
|
|
|
|
if (ei->i_reserved_data_blocks == 0) {
|
|
/*
|
|
* We can release all of the reserved metadata blocks
|
|
* only when we have written all of the delayed
|
|
* allocation blocks.
|
|
* Note that in case of bigalloc, i_reserved_meta_blocks,
|
|
* i_reserved_data_blocks, etc. refer to number of clusters.
|
|
*/
|
|
percpu_counter_sub(&sbi->s_dirtyclusters_counter,
|
|
ei->i_reserved_meta_blocks);
|
|
ei->i_reserved_meta_blocks = 0;
|
|
ei->i_da_metadata_calc_len = 0;
|
|
}
|
|
|
|
/* update fs dirty data blocks counter */
|
|
percpu_counter_sub(&sbi->s_dirtyclusters_counter, to_free);
|
|
|
|
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
|
|
|
|
dquot_release_reservation_block(inode, EXT4_C2B(sbi, to_free));
|
|
}
|
|
|
|
static void ext4_da_page_release_reservation(struct page *page,
|
|
unsigned long offset)
|
|
{
|
|
int to_release = 0;
|
|
struct buffer_head *head, *bh;
|
|
unsigned int curr_off = 0;
|
|
struct inode *inode = page->mapping->host;
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
int num_clusters;
|
|
ext4_fsblk_t lblk;
|
|
|
|
head = page_buffers(page);
|
|
bh = head;
|
|
do {
|
|
unsigned int next_off = curr_off + bh->b_size;
|
|
|
|
if ((offset <= curr_off) && (buffer_delay(bh))) {
|
|
to_release++;
|
|
clear_buffer_delay(bh);
|
|
}
|
|
curr_off = next_off;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
|
|
if (to_release) {
|
|
lblk = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
ext4_es_remove_extent(inode, lblk, to_release);
|
|
}
|
|
|
|
/* If we have released all the blocks belonging to a cluster, then we
|
|
* need to release the reserved space for that cluster. */
|
|
num_clusters = EXT4_NUM_B2C(sbi, to_release);
|
|
while (num_clusters > 0) {
|
|
lblk = (page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits)) +
|
|
((num_clusters - 1) << sbi->s_cluster_bits);
|
|
if (sbi->s_cluster_ratio == 1 ||
|
|
!ext4_find_delalloc_cluster(inode, lblk))
|
|
ext4_da_release_space(inode, 1);
|
|
|
|
num_clusters--;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Delayed allocation stuff
|
|
*/
|
|
|
|
/*
|
|
* mpage_da_submit_io - walks through extent of pages and try to write
|
|
* them with writepage() call back
|
|
*
|
|
* @mpd->inode: inode
|
|
* @mpd->first_page: first page of the extent
|
|
* @mpd->next_page: page after the last page of the extent
|
|
*
|
|
* By the time mpage_da_submit_io() is called we expect all blocks
|
|
* to be allocated. this may be wrong if allocation failed.
|
|
*
|
|
* As pages are already locked by write_cache_pages(), we can't use it
|
|
*/
|
|
static int mpage_da_submit_io(struct mpage_da_data *mpd,
|
|
struct ext4_map_blocks *map)
|
|
{
|
|
struct pagevec pvec;
|
|
unsigned long index, end;
|
|
int ret = 0, err, nr_pages, i;
|
|
struct inode *inode = mpd->inode;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
loff_t size = i_size_read(inode);
|
|
unsigned int len, block_start;
|
|
struct buffer_head *bh, *page_bufs = NULL;
|
|
int journal_data = ext4_should_journal_data(inode);
|
|
sector_t pblock = 0, cur_logical = 0;
|
|
struct ext4_io_submit io_submit;
|
|
|
|
BUG_ON(mpd->next_page <= mpd->first_page);
|
|
memset(&io_submit, 0, sizeof(io_submit));
|
|
/*
|
|
* We need to start from the first_page to the next_page - 1
|
|
* to make sure we also write the mapped dirty buffer_heads.
|
|
* If we look at mpd->b_blocknr we would only be looking
|
|
* at the currently mapped buffer_heads.
|
|
*/
|
|
index = mpd->first_page;
|
|
end = mpd->next_page - 1;
|
|
|
|
pagevec_init(&pvec, 0);
|
|
while (index <= end) {
|
|
nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
|
|
if (nr_pages == 0)
|
|
break;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
int commit_write = 0, skip_page = 0;
|
|
struct page *page = pvec.pages[i];
|
|
|
|
index = page->index;
|
|
if (index > end)
|
|
break;
|
|
|
|
if (index == size >> PAGE_CACHE_SHIFT)
|
|
len = size & ~PAGE_CACHE_MASK;
|
|
else
|
|
len = PAGE_CACHE_SIZE;
|
|
if (map) {
|
|
cur_logical = index << (PAGE_CACHE_SHIFT -
|
|
inode->i_blkbits);
|
|
pblock = map->m_pblk + (cur_logical -
|
|
map->m_lblk);
|
|
}
|
|
index++;
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
BUG_ON(PageWriteback(page));
|
|
|
|
/*
|
|
* If the page does not have buffers (for
|
|
* whatever reason), try to create them using
|
|
* __block_write_begin. If this fails,
|
|
* skip the page and move on.
|
|
*/
|
|
if (!page_has_buffers(page)) {
|
|
if (__block_write_begin(page, 0, len,
|
|
noalloc_get_block_write)) {
|
|
skip_page:
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
commit_write = 1;
|
|
}
|
|
|
|
bh = page_bufs = page_buffers(page);
|
|
block_start = 0;
|
|
do {
|
|
if (!bh)
|
|
goto skip_page;
|
|
if (map && (cur_logical >= map->m_lblk) &&
|
|
(cur_logical <= (map->m_lblk +
|
|
(map->m_len - 1)))) {
|
|
if (buffer_delay(bh)) {
|
|
clear_buffer_delay(bh);
|
|
bh->b_blocknr = pblock;
|
|
}
|
|
if (buffer_unwritten(bh) ||
|
|
buffer_mapped(bh))
|
|
BUG_ON(bh->b_blocknr != pblock);
|
|
if (map->m_flags & EXT4_MAP_UNINIT)
|
|
set_buffer_uninit(bh);
|
|
clear_buffer_unwritten(bh);
|
|
}
|
|
|
|
/*
|
|
* skip page if block allocation undone and
|
|
* block is dirty
|
|
*/
|
|
if (ext4_bh_delay_or_unwritten(NULL, bh))
|
|
skip_page = 1;
|
|
bh = bh->b_this_page;
|
|
block_start += bh->b_size;
|
|
cur_logical++;
|
|
pblock++;
|
|
} while (bh != page_bufs);
|
|
|
|
if (skip_page)
|
|
goto skip_page;
|
|
|
|
if (commit_write)
|
|
/* mark the buffer_heads as dirty & uptodate */
|
|
block_commit_write(page, 0, len);
|
|
|
|
clear_page_dirty_for_io(page);
|
|
/*
|
|
* Delalloc doesn't support data journalling,
|
|
* but eventually maybe we'll lift this
|
|
* restriction.
|
|
*/
|
|
if (unlikely(journal_data && PageChecked(page)))
|
|
err = __ext4_journalled_writepage(page, len);
|
|
else if (test_opt(inode->i_sb, MBLK_IO_SUBMIT))
|
|
err = ext4_bio_write_page(&io_submit, page,
|
|
len, mpd->wbc);
|
|
else if (buffer_uninit(page_bufs)) {
|
|
ext4_set_bh_endio(page_bufs, inode);
|
|
err = block_write_full_page_endio(page,
|
|
noalloc_get_block_write,
|
|
mpd->wbc, ext4_end_io_buffer_write);
|
|
} else
|
|
err = block_write_full_page(page,
|
|
noalloc_get_block_write, mpd->wbc);
|
|
|
|
if (!err)
|
|
mpd->pages_written++;
|
|
/*
|
|
* In error case, we have to continue because
|
|
* remaining pages are still locked
|
|
*/
|
|
if (ret == 0)
|
|
ret = err;
|
|
}
|
|
pagevec_release(&pvec);
|
|
}
|
|
ext4_io_submit(&io_submit);
|
|
return ret;
|
|
}
|
|
|
|
static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd)
|
|
{
|
|
int nr_pages, i;
|
|
pgoff_t index, end;
|
|
struct pagevec pvec;
|
|
struct inode *inode = mpd->inode;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
ext4_lblk_t start, last;
|
|
|
|
index = mpd->first_page;
|
|
end = mpd->next_page - 1;
|
|
|
|
start = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
last = end << (PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
ext4_es_remove_extent(inode, start, last - start + 1);
|
|
|
|
pagevec_init(&pvec, 0);
|
|
while (index <= end) {
|
|
nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
|
|
if (nr_pages == 0)
|
|
break;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec.pages[i];
|
|
if (page->index > end)
|
|
break;
|
|
BUG_ON(!PageLocked(page));
|
|
BUG_ON(PageWriteback(page));
|
|
block_invalidatepage(page, 0);
|
|
ClearPageUptodate(page);
|
|
unlock_page(page);
|
|
}
|
|
index = pvec.pages[nr_pages - 1]->index + 1;
|
|
pagevec_release(&pvec);
|
|
}
|
|
return;
|
|
}
|
|
|
|
static void ext4_print_free_blocks(struct inode *inode)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
ext4_msg(sb, KERN_CRIT, "Total free blocks count %lld",
|
|
EXT4_C2B(EXT4_SB(inode->i_sb),
|
|
ext4_count_free_clusters(inode->i_sb)));
|
|
ext4_msg(sb, KERN_CRIT, "Free/Dirty block details");
|
|
ext4_msg(sb, KERN_CRIT, "free_blocks=%lld",
|
|
(long long) EXT4_C2B(EXT4_SB(inode->i_sb),
|
|
percpu_counter_sum(&sbi->s_freeclusters_counter)));
|
|
ext4_msg(sb, KERN_CRIT, "dirty_blocks=%lld",
|
|
(long long) EXT4_C2B(EXT4_SB(inode->i_sb),
|
|
percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
|
|
ext4_msg(sb, KERN_CRIT, "Block reservation details");
|
|
ext4_msg(sb, KERN_CRIT, "i_reserved_data_blocks=%u",
|
|
EXT4_I(inode)->i_reserved_data_blocks);
|
|
ext4_msg(sb, KERN_CRIT, "i_reserved_meta_blocks=%u",
|
|
EXT4_I(inode)->i_reserved_meta_blocks);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* mpage_da_map_and_submit - go through given space, map them
|
|
* if necessary, and then submit them for I/O
|
|
*
|
|
* @mpd - bh describing space
|
|
*
|
|
* The function skips space we know is already mapped to disk blocks.
|
|
*
|
|
*/
|
|
static void mpage_da_map_and_submit(struct mpage_da_data *mpd)
|
|
{
|
|
int err, blks, get_blocks_flags;
|
|
struct ext4_map_blocks map, *mapp = NULL;
|
|
sector_t next = mpd->b_blocknr;
|
|
unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits;
|
|
loff_t disksize = EXT4_I(mpd->inode)->i_disksize;
|
|
handle_t *handle = NULL;
|
|
|
|
/*
|
|
* If the blocks are mapped already, or we couldn't accumulate
|
|
* any blocks, then proceed immediately to the submission stage.
|
|
*/
|
|
if ((mpd->b_size == 0) ||
|
|
((mpd->b_state & (1 << BH_Mapped)) &&
|
|
!(mpd->b_state & (1 << BH_Delay)) &&
|
|
!(mpd->b_state & (1 << BH_Unwritten))))
|
|
goto submit_io;
|
|
|
|
handle = ext4_journal_current_handle();
|
|
BUG_ON(!handle);
|
|
|
|
/*
|
|
* Call ext4_map_blocks() to allocate any delayed allocation
|
|
* blocks, or to convert an uninitialized extent to be
|
|
* initialized (in the case where we have written into
|
|
* one or more preallocated blocks).
|
|
*
|
|
* We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to
|
|
* indicate that we are on the delayed allocation path. This
|
|
* affects functions in many different parts of the allocation
|
|
* call path. This flag exists primarily because we don't
|
|
* want to change *many* call functions, so ext4_map_blocks()
|
|
* will set the EXT4_STATE_DELALLOC_RESERVED flag once the
|
|
* inode's allocation semaphore is taken.
|
|
*
|
|
* If the blocks in questions were delalloc blocks, set
|
|
* EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting
|
|
* variables are updated after the blocks have been allocated.
|
|
*/
|
|
map.m_lblk = next;
|
|
map.m_len = max_blocks;
|
|
get_blocks_flags = EXT4_GET_BLOCKS_CREATE;
|
|
if (ext4_should_dioread_nolock(mpd->inode))
|
|
get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT;
|
|
if (mpd->b_state & (1 << BH_Delay))
|
|
get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE;
|
|
|
|
blks = ext4_map_blocks(handle, mpd->inode, &map, get_blocks_flags);
|
|
if (blks < 0) {
|
|
struct super_block *sb = mpd->inode->i_sb;
|
|
|
|
err = blks;
|
|
/*
|
|
* If get block returns EAGAIN or ENOSPC and there
|
|
* appears to be free blocks we will just let
|
|
* mpage_da_submit_io() unlock all of the pages.
|
|
*/
|
|
if (err == -EAGAIN)
|
|
goto submit_io;
|
|
|
|
if (err == -ENOSPC && ext4_count_free_clusters(sb)) {
|
|
mpd->retval = err;
|
|
goto submit_io;
|
|
}
|
|
|
|
/*
|
|
* get block failure will cause us to loop in
|
|
* writepages, because a_ops->writepage won't be able
|
|
* to make progress. The page will be redirtied by
|
|
* writepage and writepages will again try to write
|
|
* the same.
|
|
*/
|
|
if (!(EXT4_SB(sb)->s_mount_flags & EXT4_MF_FS_ABORTED)) {
|
|
ext4_msg(sb, KERN_CRIT,
|
|
"delayed block allocation failed for inode %lu "
|
|
"at logical offset %llu with max blocks %zd "
|
|
"with error %d", mpd->inode->i_ino,
|
|
(unsigned long long) next,
|
|
mpd->b_size >> mpd->inode->i_blkbits, err);
|
|
ext4_msg(sb, KERN_CRIT,
|
|
"This should not happen!! Data will be lost\n");
|
|
if (err == -ENOSPC)
|
|
ext4_print_free_blocks(mpd->inode);
|
|
}
|
|
/* invalidate all the pages */
|
|
ext4_da_block_invalidatepages(mpd);
|
|
|
|
/* Mark this page range as having been completed */
|
|
mpd->io_done = 1;
|
|
return;
|
|
}
|
|
BUG_ON(blks == 0);
|
|
|
|
mapp = ↦
|
|
if (map.m_flags & EXT4_MAP_NEW) {
|
|
struct block_device *bdev = mpd->inode->i_sb->s_bdev;
|
|
int i;
|
|
|
|
for (i = 0; i < map.m_len; i++)
|
|
unmap_underlying_metadata(bdev, map.m_pblk + i);
|
|
}
|
|
|
|
/*
|
|
* Update on-disk size along with block allocation.
|
|
*/
|
|
disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits;
|
|
if (disksize > i_size_read(mpd->inode))
|
|
disksize = i_size_read(mpd->inode);
|
|
if (disksize > EXT4_I(mpd->inode)->i_disksize) {
|
|
ext4_update_i_disksize(mpd->inode, disksize);
|
|
err = ext4_mark_inode_dirty(handle, mpd->inode);
|
|
if (err)
|
|
ext4_error(mpd->inode->i_sb,
|
|
"Failed to mark inode %lu dirty",
|
|
mpd->inode->i_ino);
|
|
}
|
|
|
|
submit_io:
|
|
mpage_da_submit_io(mpd, mapp);
|
|
mpd->io_done = 1;
|
|
}
|
|
|
|
#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
|
|
(1 << BH_Delay) | (1 << BH_Unwritten))
|
|
|
|
/*
|
|
* mpage_add_bh_to_extent - try to add one more block to extent of blocks
|
|
*
|
|
* @mpd->lbh - extent of blocks
|
|
* @logical - logical number of the block in the file
|
|
* @bh - bh of the block (used to access block's state)
|
|
*
|
|
* the function is used to collect contig. blocks in same state
|
|
*/
|
|
static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
|
|
sector_t logical, size_t b_size,
|
|
unsigned long b_state)
|
|
{
|
|
sector_t next;
|
|
int nrblocks = mpd->b_size >> mpd->inode->i_blkbits;
|
|
|
|
/*
|
|
* XXX Don't go larger than mballoc is willing to allocate
|
|
* This is a stopgap solution. We eventually need to fold
|
|
* mpage_da_submit_io() into this function and then call
|
|
* ext4_map_blocks() multiple times in a loop
|
|
*/
|
|
if (nrblocks >= 8*1024*1024/mpd->inode->i_sb->s_blocksize)
|
|
goto flush_it;
|
|
|
|
/* check if thereserved journal credits might overflow */
|
|
if (!(ext4_test_inode_flag(mpd->inode, EXT4_INODE_EXTENTS))) {
|
|
if (nrblocks >= EXT4_MAX_TRANS_DATA) {
|
|
/*
|
|
* With non-extent format we are limited by the journal
|
|
* credit available. Total credit needed to insert
|
|
* nrblocks contiguous blocks is dependent on the
|
|
* nrblocks. So limit nrblocks.
|
|
*/
|
|
goto flush_it;
|
|
} else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) >
|
|
EXT4_MAX_TRANS_DATA) {
|
|
/*
|
|
* Adding the new buffer_head would make it cross the
|
|
* allowed limit for which we have journal credit
|
|
* reserved. So limit the new bh->b_size
|
|
*/
|
|
b_size = (EXT4_MAX_TRANS_DATA - nrblocks) <<
|
|
mpd->inode->i_blkbits;
|
|
/* we will do mpage_da_submit_io in the next loop */
|
|
}
|
|
}
|
|
/*
|
|
* First block in the extent
|
|
*/
|
|
if (mpd->b_size == 0) {
|
|
mpd->b_blocknr = logical;
|
|
mpd->b_size = b_size;
|
|
mpd->b_state = b_state & BH_FLAGS;
|
|
return;
|
|
}
|
|
|
|
next = mpd->b_blocknr + nrblocks;
|
|
/*
|
|
* Can we merge the block to our big extent?
|
|
*/
|
|
if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) {
|
|
mpd->b_size += b_size;
|
|
return;
|
|
}
|
|
|
|
flush_it:
|
|
/*
|
|
* We couldn't merge the block to our extent, so we
|
|
* need to flush current extent and start new one
|
|
*/
|
|
mpage_da_map_and_submit(mpd);
|
|
return;
|
|
}
|
|
|
|
static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
return (buffer_delay(bh) || buffer_unwritten(bh)) && buffer_dirty(bh);
|
|
}
|
|
|
|
/*
|
|
* This function is grabs code from the very beginning of
|
|
* ext4_map_blocks, but assumes that the caller is from delayed write
|
|
* time. This function looks up the requested blocks and sets the
|
|
* buffer delay bit under the protection of i_data_sem.
|
|
*/
|
|
static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
|
|
struct ext4_map_blocks *map,
|
|
struct buffer_head *bh)
|
|
{
|
|
int retval;
|
|
sector_t invalid_block = ~((sector_t) 0xffff);
|
|
|
|
if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
|
|
invalid_block = ~0;
|
|
|
|
map->m_flags = 0;
|
|
ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
|
|
"logical block %lu\n", inode->i_ino, map->m_len,
|
|
(unsigned long) map->m_lblk);
|
|
/*
|
|
* Try to see if we can get the block without requesting a new
|
|
* file system block.
|
|
*/
|
|
down_read((&EXT4_I(inode)->i_data_sem));
|
|
if (ext4_has_inline_data(inode)) {
|
|
/*
|
|
* We will soon create blocks for this page, and let
|
|
* us pretend as if the blocks aren't allocated yet.
|
|
* In case of clusters, we have to handle the work
|
|
* of mapping from cluster so that the reserved space
|
|
* is calculated properly.
|
|
*/
|
|
if ((EXT4_SB(inode->i_sb)->s_cluster_ratio > 1) &&
|
|
ext4_find_delalloc_cluster(inode, map->m_lblk))
|
|
map->m_flags |= EXT4_MAP_FROM_CLUSTER;
|
|
retval = 0;
|
|
} else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
retval = ext4_ext_map_blocks(NULL, inode, map, 0);
|
|
else
|
|
retval = ext4_ind_map_blocks(NULL, inode, map, 0);
|
|
|
|
if (retval == 0) {
|
|
/*
|
|
* XXX: __block_prepare_write() unmaps passed block,
|
|
* is it OK?
|
|
*/
|
|
/* If the block was allocated from previously allocated cluster,
|
|
* then we dont need to reserve it again. */
|
|
if (!(map->m_flags & EXT4_MAP_FROM_CLUSTER)) {
|
|
retval = ext4_da_reserve_space(inode, iblock);
|
|
if (retval)
|
|
/* not enough space to reserve */
|
|
goto out_unlock;
|
|
}
|
|
|
|
retval = ext4_es_insert_extent(inode, map->m_lblk, map->m_len);
|
|
if (retval)
|
|
goto out_unlock;
|
|
|
|
/* Clear EXT4_MAP_FROM_CLUSTER flag since its purpose is served
|
|
* and it should not appear on the bh->b_state.
|
|
*/
|
|
map->m_flags &= ~EXT4_MAP_FROM_CLUSTER;
|
|
|
|
map_bh(bh, inode->i_sb, invalid_block);
|
|
set_buffer_new(bh);
|
|
set_buffer_delay(bh);
|
|
}
|
|
|
|
out_unlock:
|
|
up_read((&EXT4_I(inode)->i_data_sem));
|
|
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* This is a special get_blocks_t callback which is used by
|
|
* ext4_da_write_begin(). It will either return mapped block or
|
|
* reserve space for a single block.
|
|
*
|
|
* For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
|
|
* We also have b_blocknr = -1 and b_bdev initialized properly
|
|
*
|
|
* For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
|
|
* We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
|
|
* initialized properly.
|
|
*/
|
|
int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh, int create)
|
|
{
|
|
struct ext4_map_blocks map;
|
|
int ret = 0;
|
|
|
|
BUG_ON(create == 0);
|
|
BUG_ON(bh->b_size != inode->i_sb->s_blocksize);
|
|
|
|
map.m_lblk = iblock;
|
|
map.m_len = 1;
|
|
|
|
/*
|
|
* first, we need to know whether the block is allocated already
|
|
* preallocated blocks are unmapped but should treated
|
|
* the same as allocated blocks.
|
|
*/
|
|
ret = ext4_da_map_blocks(inode, iblock, &map, bh);
|
|
if (ret <= 0)
|
|
return ret;
|
|
|
|
map_bh(bh, inode->i_sb, map.m_pblk);
|
|
bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
|
|
|
|
if (buffer_unwritten(bh)) {
|
|
/* A delayed write to unwritten bh should be marked
|
|
* new and mapped. Mapped ensures that we don't do
|
|
* get_block multiple times when we write to the same
|
|
* offset and new ensures that we do proper zero out
|
|
* for partial write.
|
|
*/
|
|
set_buffer_new(bh);
|
|
set_buffer_mapped(bh);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This function is used as a standard get_block_t calback function
|
|
* when there is no desire to allocate any blocks. It is used as a
|
|
* callback function for block_write_begin() and block_write_full_page().
|
|
* These functions should only try to map a single block at a time.
|
|
*
|
|
* Since this function doesn't do block allocations even if the caller
|
|
* requests it by passing in create=1, it is critically important that
|
|
* any caller checks to make sure that any buffer heads are returned
|
|
* by this function are either all already mapped or marked for
|
|
* delayed allocation before calling block_write_full_page(). Otherwise,
|
|
* b_blocknr could be left unitialized, and the page write functions will
|
|
* be taken by surprise.
|
|
*/
|
|
static int noalloc_get_block_write(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create)
|
|
{
|
|
BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);
|
|
return _ext4_get_block(inode, iblock, bh_result, 0);
|
|
}
|
|
|
|
static int bget_one(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
get_bh(bh);
|
|
return 0;
|
|
}
|
|
|
|
static int bput_one(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
put_bh(bh);
|
|
return 0;
|
|
}
|
|
|
|
static int __ext4_journalled_writepage(struct page *page,
|
|
unsigned int len)
|
|
{
|
|
struct address_space *mapping = page->mapping;
|
|
struct inode *inode = mapping->host;
|
|
struct buffer_head *page_bufs = NULL;
|
|
handle_t *handle = NULL;
|
|
int ret = 0, err = 0;
|
|
int inline_data = ext4_has_inline_data(inode);
|
|
struct buffer_head *inode_bh = NULL;
|
|
|
|
ClearPageChecked(page);
|
|
|
|
if (inline_data) {
|
|
BUG_ON(page->index != 0);
|
|
BUG_ON(len > ext4_get_max_inline_size(inode));
|
|
inode_bh = ext4_journalled_write_inline_data(inode, len, page);
|
|
if (inode_bh == NULL)
|
|
goto out;
|
|
} else {
|
|
page_bufs = page_buffers(page);
|
|
if (!page_bufs) {
|
|
BUG();
|
|
goto out;
|
|
}
|
|
ext4_walk_page_buffers(handle, page_bufs, 0, len,
|
|
NULL, bget_one);
|
|
}
|
|
/* As soon as we unlock the page, it can go away, but we have
|
|
* references to buffers so we are safe */
|
|
unlock_page(page);
|
|
|
|
handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
goto out;
|
|
}
|
|
|
|
BUG_ON(!ext4_handle_valid(handle));
|
|
|
|
if (inline_data) {
|
|
ret = ext4_journal_get_write_access(handle, inode_bh);
|
|
|
|
err = ext4_handle_dirty_metadata(handle, inode, inode_bh);
|
|
|
|
} else {
|
|
ret = ext4_walk_page_buffers(handle, page_bufs, 0, len, NULL,
|
|
do_journal_get_write_access);
|
|
|
|
err = ext4_walk_page_buffers(handle, page_bufs, 0, len, NULL,
|
|
write_end_fn);
|
|
}
|
|
if (ret == 0)
|
|
ret = err;
|
|
EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
|
|
err = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = err;
|
|
|
|
if (!ext4_has_inline_data(inode))
|
|
ext4_walk_page_buffers(handle, page_bufs, 0, len,
|
|
NULL, bput_one);
|
|
ext4_set_inode_state(inode, EXT4_STATE_JDATA);
|
|
out:
|
|
brelse(inode_bh);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Note that we don't need to start a transaction unless we're journaling data
|
|
* because we should have holes filled from ext4_page_mkwrite(). We even don't
|
|
* need to file the inode to the transaction's list in ordered mode because if
|
|
* we are writing back data added by write(), the inode is already there and if
|
|
* we are writing back data modified via mmap(), no one guarantees in which
|
|
* transaction the data will hit the disk. In case we are journaling data, we
|
|
* cannot start transaction directly because transaction start ranks above page
|
|
* lock so we have to do some magic.
|
|
*
|
|
* This function can get called via...
|
|
* - ext4_da_writepages after taking page lock (have journal handle)
|
|
* - journal_submit_inode_data_buffers (no journal handle)
|
|
* - shrink_page_list via the kswapd/direct reclaim (no journal handle)
|
|
* - grab_page_cache when doing write_begin (have journal handle)
|
|
*
|
|
* We don't do any block allocation in this function. If we have page with
|
|
* multiple blocks we need to write those buffer_heads that are mapped. This
|
|
* is important for mmaped based write. So if we do with blocksize 1K
|
|
* truncate(f, 1024);
|
|
* a = mmap(f, 0, 4096);
|
|
* a[0] = 'a';
|
|
* truncate(f, 4096);
|
|
* we have in the page first buffer_head mapped via page_mkwrite call back
|
|
* but other buffer_heads would be unmapped but dirty (dirty done via the
|
|
* do_wp_page). So writepage should write the first block. If we modify
|
|
* the mmap area beyond 1024 we will again get a page_fault and the
|
|
* page_mkwrite callback will do the block allocation and mark the
|
|
* buffer_heads mapped.
|
|
*
|
|
* We redirty the page if we have any buffer_heads that is either delay or
|
|
* unwritten in the page.
|
|
*
|
|
* We can get recursively called as show below.
|
|
*
|
|
* ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
|
|
* ext4_writepage()
|
|
*
|
|
* But since we don't do any block allocation we should not deadlock.
|
|
* Page also have the dirty flag cleared so we don't get recurive page_lock.
|
|
*/
|
|
static int ext4_writepage(struct page *page,
|
|
struct writeback_control *wbc)
|
|
{
|
|
int ret = 0, commit_write = 0;
|
|
loff_t size;
|
|
unsigned int len;
|
|
struct buffer_head *page_bufs = NULL;
|
|
struct inode *inode = page->mapping->host;
|
|
|
|
trace_ext4_writepage(page);
|
|
size = i_size_read(inode);
|
|
if (page->index == size >> PAGE_CACHE_SHIFT)
|
|
len = size & ~PAGE_CACHE_MASK;
|
|
else
|
|
len = PAGE_CACHE_SIZE;
|
|
|
|
/*
|
|
* If the page does not have buffers (for whatever reason),
|
|
* try to create them using __block_write_begin. If this
|
|
* fails, redirty the page and move on.
|
|
*/
|
|
if (!page_has_buffers(page)) {
|
|
if (__block_write_begin(page, 0, len,
|
|
noalloc_get_block_write)) {
|
|
redirty_page:
|
|
redirty_page_for_writepage(wbc, page);
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
commit_write = 1;
|
|
}
|
|
page_bufs = page_buffers(page);
|
|
if (ext4_walk_page_buffers(NULL, page_bufs, 0, len, NULL,
|
|
ext4_bh_delay_or_unwritten)) {
|
|
/*
|
|
* We don't want to do block allocation, so redirty
|
|
* the page and return. We may reach here when we do
|
|
* a journal commit via journal_submit_inode_data_buffers.
|
|
* We can also reach here via shrink_page_list but it
|
|
* should never be for direct reclaim so warn if that
|
|
* happens
|
|
*/
|
|
WARN_ON_ONCE((current->flags & (PF_MEMALLOC|PF_KSWAPD)) ==
|
|
PF_MEMALLOC);
|
|
goto redirty_page;
|
|
}
|
|
if (commit_write)
|
|
/* now mark the buffer_heads as dirty and uptodate */
|
|
block_commit_write(page, 0, len);
|
|
|
|
if (PageChecked(page) && ext4_should_journal_data(inode))
|
|
/*
|
|
* It's mmapped pagecache. Add buffers and journal it. There
|
|
* doesn't seem much point in redirtying the page here.
|
|
*/
|
|
return __ext4_journalled_writepage(page, len);
|
|
|
|
if (buffer_uninit(page_bufs)) {
|
|
ext4_set_bh_endio(page_bufs, inode);
|
|
ret = block_write_full_page_endio(page, noalloc_get_block_write,
|
|
wbc, ext4_end_io_buffer_write);
|
|
} else
|
|
ret = block_write_full_page(page, noalloc_get_block_write,
|
|
wbc);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* This is called via ext4_da_writepages() to
|
|
* calculate the total number of credits to reserve to fit
|
|
* a single extent allocation into a single transaction,
|
|
* ext4_da_writpeages() will loop calling this before
|
|
* the block allocation.
|
|
*/
|
|
|
|
static int ext4_da_writepages_trans_blocks(struct inode *inode)
|
|
{
|
|
int max_blocks = EXT4_I(inode)->i_reserved_data_blocks;
|
|
|
|
/*
|
|
* With non-extent format the journal credit needed to
|
|
* insert nrblocks contiguous block is dependent on
|
|
* number of contiguous block. So we will limit
|
|
* number of contiguous block to a sane value
|
|
*/
|
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) &&
|
|
(max_blocks > EXT4_MAX_TRANS_DATA))
|
|
max_blocks = EXT4_MAX_TRANS_DATA;
|
|
|
|
return ext4_chunk_trans_blocks(inode, max_blocks);
|
|
}
|
|
|
|
/*
|
|
* write_cache_pages_da - walk the list of dirty pages of the given
|
|
* address space and accumulate pages that need writing, and call
|
|
* mpage_da_map_and_submit to map a single contiguous memory region
|
|
* and then write them.
|
|
*/
|
|
static int write_cache_pages_da(handle_t *handle,
|
|
struct address_space *mapping,
|
|
struct writeback_control *wbc,
|
|
struct mpage_da_data *mpd,
|
|
pgoff_t *done_index)
|
|
{
|
|
struct buffer_head *bh, *head;
|
|
struct inode *inode = mapping->host;
|
|
struct pagevec pvec;
|
|
unsigned int nr_pages;
|
|
sector_t logical;
|
|
pgoff_t index, end;
|
|
long nr_to_write = wbc->nr_to_write;
|
|
int i, tag, ret = 0;
|
|
|
|
memset(mpd, 0, sizeof(struct mpage_da_data));
|
|
mpd->wbc = wbc;
|
|
mpd->inode = inode;
|
|
pagevec_init(&pvec, 0);
|
|
index = wbc->range_start >> PAGE_CACHE_SHIFT;
|
|
end = wbc->range_end >> PAGE_CACHE_SHIFT;
|
|
|
|
if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
|
|
tag = PAGECACHE_TAG_TOWRITE;
|
|
else
|
|
tag = PAGECACHE_TAG_DIRTY;
|
|
|
|
*done_index = index;
|
|
while (index <= end) {
|
|
nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
|
|
min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
|
|
if (nr_pages == 0)
|
|
return 0;
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec.pages[i];
|
|
|
|
/*
|
|
* At this point, the page may be truncated or
|
|
* invalidated (changing page->mapping to NULL), or
|
|
* even swizzled back from swapper_space to tmpfs file
|
|
* mapping. However, page->index will not change
|
|
* because we have a reference on the page.
|
|
*/
|
|
if (page->index > end)
|
|
goto out;
|
|
|
|
*done_index = page->index + 1;
|
|
|
|
/*
|
|
* If we can't merge this page, and we have
|
|
* accumulated an contiguous region, write it
|
|
*/
|
|
if ((mpd->next_page != page->index) &&
|
|
(mpd->next_page != mpd->first_page)) {
|
|
mpage_da_map_and_submit(mpd);
|
|
goto ret_extent_tail;
|
|
}
|
|
|
|
lock_page(page);
|
|
|
|
/*
|
|
* If the page is no longer dirty, or its
|
|
* mapping no longer corresponds to inode we
|
|
* are writing (which means it has been
|
|
* truncated or invalidated), or the page is
|
|
* already under writeback and we are not
|
|
* doing a data integrity writeback, skip the page
|
|
*/
|
|
if (!PageDirty(page) ||
|
|
(PageWriteback(page) &&
|
|
(wbc->sync_mode == WB_SYNC_NONE)) ||
|
|
unlikely(page->mapping != mapping)) {
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
wait_on_page_writeback(page);
|
|
BUG_ON(PageWriteback(page));
|
|
|
|
/*
|
|
* If we have inline data and arrive here, it means that
|
|
* we will soon create the block for the 1st page, so
|
|
* we'd better clear the inline data here.
|
|
*/
|
|
if (ext4_has_inline_data(inode)) {
|
|
BUG_ON(ext4_test_inode_state(inode,
|
|
EXT4_STATE_MAY_INLINE_DATA));
|
|
ext4_destroy_inline_data(handle, inode);
|
|
}
|
|
|
|
if (mpd->next_page != page->index)
|
|
mpd->first_page = page->index;
|
|
mpd->next_page = page->index + 1;
|
|
logical = (sector_t) page->index <<
|
|
(PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
|
|
if (!page_has_buffers(page)) {
|
|
mpage_add_bh_to_extent(mpd, logical,
|
|
PAGE_CACHE_SIZE,
|
|
(1 << BH_Dirty) | (1 << BH_Uptodate));
|
|
if (mpd->io_done)
|
|
goto ret_extent_tail;
|
|
} else {
|
|
/*
|
|
* Page with regular buffer heads,
|
|
* just add all dirty ones
|
|
*/
|
|
head = page_buffers(page);
|
|
bh = head;
|
|
do {
|
|
BUG_ON(buffer_locked(bh));
|
|
/*
|
|
* We need to try to allocate
|
|
* unmapped blocks in the same page.
|
|
* Otherwise we won't make progress
|
|
* with the page in ext4_writepage
|
|
*/
|
|
if (ext4_bh_delay_or_unwritten(NULL, bh)) {
|
|
mpage_add_bh_to_extent(mpd, logical,
|
|
bh->b_size,
|
|
bh->b_state);
|
|
if (mpd->io_done)
|
|
goto ret_extent_tail;
|
|
} else if (buffer_dirty(bh) && (buffer_mapped(bh))) {
|
|
/*
|
|
* mapped dirty buffer. We need
|
|
* to update the b_state
|
|
* because we look at b_state
|
|
* in mpage_da_map_blocks. We
|
|
* don't update b_size because
|
|
* if we find an unmapped
|
|
* buffer_head later we need to
|
|
* use the b_state flag of that
|
|
* buffer_head.
|
|
*/
|
|
if (mpd->b_size == 0)
|
|
mpd->b_state = bh->b_state & BH_FLAGS;
|
|
}
|
|
logical++;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
}
|
|
|
|
if (nr_to_write > 0) {
|
|
nr_to_write--;
|
|
if (nr_to_write == 0 &&
|
|
wbc->sync_mode == WB_SYNC_NONE)
|
|
/*
|
|
* We stop writing back only if we are
|
|
* not doing integrity sync. In case of
|
|
* integrity sync we have to keep going
|
|
* because someone may be concurrently
|
|
* dirtying pages, and we might have
|
|
* synced a lot of newly appeared dirty
|
|
* pages, but have not synced all of the
|
|
* old dirty pages.
|
|
*/
|
|
goto out;
|
|
}
|
|
}
|
|
pagevec_release(&pvec);
|
|
cond_resched();
|
|
}
|
|
return 0;
|
|
ret_extent_tail:
|
|
ret = MPAGE_DA_EXTENT_TAIL;
|
|
out:
|
|
pagevec_release(&pvec);
|
|
cond_resched();
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int ext4_da_writepages(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
pgoff_t index;
|
|
int range_whole = 0;
|
|
handle_t *handle = NULL;
|
|
struct mpage_da_data mpd;
|
|
struct inode *inode = mapping->host;
|
|
int pages_written = 0;
|
|
unsigned int max_pages;
|
|
int range_cyclic, cycled = 1, io_done = 0;
|
|
int needed_blocks, ret = 0;
|
|
long desired_nr_to_write, nr_to_writebump = 0;
|
|
loff_t range_start = wbc->range_start;
|
|
struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
|
|
pgoff_t done_index = 0;
|
|
pgoff_t end;
|
|
struct blk_plug plug;
|
|
|
|
trace_ext4_da_writepages(inode, wbc);
|
|
|
|
/*
|
|
* No pages to write? This is mainly a kludge to avoid starting
|
|
* a transaction for special inodes like journal inode on last iput()
|
|
* because that could violate lock ordering on umount
|
|
*/
|
|
if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
|
|
return 0;
|
|
|
|
/*
|
|
* If the filesystem has aborted, it is read-only, so return
|
|
* right away instead of dumping stack traces later on that
|
|
* will obscure the real source of the problem. We test
|
|
* EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
|
|
* the latter could be true if the filesystem is mounted
|
|
* read-only, and in that case, ext4_da_writepages should
|
|
* *never* be called, so if that ever happens, we would want
|
|
* the stack trace.
|
|
*/
|
|
if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED))
|
|
return -EROFS;
|
|
|
|
if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
|
|
range_whole = 1;
|
|
|
|
range_cyclic = wbc->range_cyclic;
|
|
if (wbc->range_cyclic) {
|
|
index = mapping->writeback_index;
|
|
if (index)
|
|
cycled = 0;
|
|
wbc->range_start = index << PAGE_CACHE_SHIFT;
|
|
wbc->range_end = LLONG_MAX;
|
|
wbc->range_cyclic = 0;
|
|
end = -1;
|
|
} else {
|
|
index = wbc->range_start >> PAGE_CACHE_SHIFT;
|
|
end = wbc->range_end >> PAGE_CACHE_SHIFT;
|
|
}
|
|
|
|
/*
|
|
* This works around two forms of stupidity. The first is in
|
|
* the writeback code, which caps the maximum number of pages
|
|
* written to be 1024 pages. This is wrong on multiple
|
|
* levels; different architectues have a different page size,
|
|
* which changes the maximum amount of data which gets
|
|
* written. Secondly, 4 megabytes is way too small. XFS
|
|
* forces this value to be 16 megabytes by multiplying
|
|
* nr_to_write parameter by four, and then relies on its
|
|
* allocator to allocate larger extents to make them
|
|
* contiguous. Unfortunately this brings us to the second
|
|
* stupidity, which is that ext4's mballoc code only allocates
|
|
* at most 2048 blocks. So we force contiguous writes up to
|
|
* the number of dirty blocks in the inode, or
|
|
* sbi->max_writeback_mb_bump whichever is smaller.
|
|
*/
|
|
max_pages = sbi->s_max_writeback_mb_bump << (20 - PAGE_CACHE_SHIFT);
|
|
if (!range_cyclic && range_whole) {
|
|
if (wbc->nr_to_write == LONG_MAX)
|
|
desired_nr_to_write = wbc->nr_to_write;
|
|
else
|
|
desired_nr_to_write = wbc->nr_to_write * 8;
|
|
} else
|
|
desired_nr_to_write = ext4_num_dirty_pages(inode, index,
|
|
max_pages);
|
|
if (desired_nr_to_write > max_pages)
|
|
desired_nr_to_write = max_pages;
|
|
|
|
if (wbc->nr_to_write < desired_nr_to_write) {
|
|
nr_to_writebump = desired_nr_to_write - wbc->nr_to_write;
|
|
wbc->nr_to_write = desired_nr_to_write;
|
|
}
|
|
|
|
retry:
|
|
if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
|
|
tag_pages_for_writeback(mapping, index, end);
|
|
|
|
blk_start_plug(&plug);
|
|
while (!ret && wbc->nr_to_write > 0) {
|
|
|
|
/*
|
|
* we insert one extent at a time. So we need
|
|
* credit needed for single extent allocation.
|
|
* journalled mode is currently not supported
|
|
* by delalloc
|
|
*/
|
|
BUG_ON(ext4_should_journal_data(inode));
|
|
needed_blocks = ext4_da_writepages_trans_blocks(inode);
|
|
|
|
/* start a new transaction*/
|
|
handle = ext4_journal_start(inode, needed_blocks);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
|
|
"%ld pages, ino %lu; err %d", __func__,
|
|
wbc->nr_to_write, inode->i_ino, ret);
|
|
blk_finish_plug(&plug);
|
|
goto out_writepages;
|
|
}
|
|
|
|
/*
|
|
* Now call write_cache_pages_da() to find the next
|
|
* contiguous region of logical blocks that need
|
|
* blocks to be allocated by ext4 and submit them.
|
|
*/
|
|
ret = write_cache_pages_da(handle, mapping,
|
|
wbc, &mpd, &done_index);
|
|
/*
|
|
* If we have a contiguous extent of pages and we
|
|
* haven't done the I/O yet, map the blocks and submit
|
|
* them for I/O.
|
|
*/
|
|
if (!mpd.io_done && mpd.next_page != mpd.first_page) {
|
|
mpage_da_map_and_submit(&mpd);
|
|
ret = MPAGE_DA_EXTENT_TAIL;
|
|
}
|
|
trace_ext4_da_write_pages(inode, &mpd);
|
|
wbc->nr_to_write -= mpd.pages_written;
|
|
|
|
ext4_journal_stop(handle);
|
|
|
|
if ((mpd.retval == -ENOSPC) && sbi->s_journal) {
|
|
/* commit the transaction which would
|
|
* free blocks released in the transaction
|
|
* and try again
|
|
*/
|
|
jbd2_journal_force_commit_nested(sbi->s_journal);
|
|
ret = 0;
|
|
} else if (ret == MPAGE_DA_EXTENT_TAIL) {
|
|
/*
|
|
* Got one extent now try with rest of the pages.
|
|
* If mpd.retval is set -EIO, journal is aborted.
|
|
* So we don't need to write any more.
|
|
*/
|
|
pages_written += mpd.pages_written;
|
|
ret = mpd.retval;
|
|
io_done = 1;
|
|
} else if (wbc->nr_to_write)
|
|
/*
|
|
* There is no more writeout needed
|
|
* or we requested for a noblocking writeout
|
|
* and we found the device congested
|
|
*/
|
|
break;
|
|
}
|
|
blk_finish_plug(&plug);
|
|
if (!io_done && !cycled) {
|
|
cycled = 1;
|
|
index = 0;
|
|
wbc->range_start = index << PAGE_CACHE_SHIFT;
|
|
wbc->range_end = mapping->writeback_index - 1;
|
|
goto retry;
|
|
}
|
|
|
|
/* Update index */
|
|
wbc->range_cyclic = range_cyclic;
|
|
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
|
|
/*
|
|
* set the writeback_index so that range_cyclic
|
|
* mode will write it back later
|
|
*/
|
|
mapping->writeback_index = done_index;
|
|
|
|
out_writepages:
|
|
wbc->nr_to_write -= nr_to_writebump;
|
|
wbc->range_start = range_start;
|
|
trace_ext4_da_writepages_result(inode, wbc, ret, pages_written);
|
|
return ret;
|
|
}
|
|
|
|
static int ext4_nonda_switch(struct super_block *sb)
|
|
{
|
|
s64 free_blocks, dirty_blocks;
|
|
struct ext4_sb_info *sbi = EXT4_SB(sb);
|
|
|
|
/*
|
|
* switch to non delalloc mode if we are running low
|
|
* on free block. The free block accounting via percpu
|
|
* counters can get slightly wrong with percpu_counter_batch getting
|
|
* accumulated on each CPU without updating global counters
|
|
* Delalloc need an accurate free block accounting. So switch
|
|
* to non delalloc when we are near to error range.
|
|
*/
|
|
free_blocks = EXT4_C2B(sbi,
|
|
percpu_counter_read_positive(&sbi->s_freeclusters_counter));
|
|
dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyclusters_counter);
|
|
/*
|
|
* Start pushing delalloc when 1/2 of free blocks are dirty.
|
|
*/
|
|
if (dirty_blocks && (free_blocks < 2 * dirty_blocks) &&
|
|
!writeback_in_progress(sb->s_bdi) &&
|
|
down_read_trylock(&sb->s_umount)) {
|
|
writeback_inodes_sb(sb, WB_REASON_FS_FREE_SPACE);
|
|
up_read(&sb->s_umount);
|
|
}
|
|
|
|
if (2 * free_blocks < 3 * dirty_blocks ||
|
|
free_blocks < (dirty_blocks + EXT4_FREECLUSTERS_WATERMARK)) {
|
|
/*
|
|
* free block count is less than 150% of dirty blocks
|
|
* or free blocks is less than watermark
|
|
*/
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
int ret, retries = 0;
|
|
struct page *page;
|
|
pgoff_t index;
|
|
struct inode *inode = mapping->host;
|
|
handle_t *handle;
|
|
|
|
index = pos >> PAGE_CACHE_SHIFT;
|
|
|
|
if (ext4_nonda_switch(inode->i_sb)) {
|
|
*fsdata = (void *)FALL_BACK_TO_NONDELALLOC;
|
|
return ext4_write_begin(file, mapping, pos,
|
|
len, flags, pagep, fsdata);
|
|
}
|
|
*fsdata = (void *)0;
|
|
trace_ext4_da_write_begin(inode, pos, len, flags);
|
|
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
|
|
ret = ext4_da_write_inline_data_begin(mapping, inode,
|
|
pos, len, flags,
|
|
pagep, fsdata);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret == 1) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
retry:
|
|
/*
|
|
* With delayed allocation, we don't log the i_disksize update
|
|
* if there is delayed block allocation. But we still need
|
|
* to journalling the i_disksize update if writes to the end
|
|
* of file which has an already mapped buffer.
|
|
*/
|
|
handle = ext4_journal_start(inode, 1);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
goto out;
|
|
}
|
|
/* We cannot recurse into the filesystem as the transaction is already
|
|
* started */
|
|
flags |= AOP_FLAG_NOFS;
|
|
|
|
page = grab_cache_page_write_begin(mapping, index, flags);
|
|
if (!page) {
|
|
ext4_journal_stop(handle);
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
*pagep = page;
|
|
|
|
ret = __block_write_begin(page, pos, len, ext4_da_get_block_prep);
|
|
if (ret < 0) {
|
|
unlock_page(page);
|
|
ext4_journal_stop(handle);
|
|
page_cache_release(page);
|
|
/*
|
|
* block_write_begin may have instantiated a few blocks
|
|
* outside i_size. Trim these off again. Don't need
|
|
* i_size_read because we hold i_mutex.
|
|
*/
|
|
if (pos + len > inode->i_size)
|
|
ext4_truncate_failed_write(inode);
|
|
}
|
|
|
|
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
|
|
goto retry;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Check if we should update i_disksize
|
|
* when write to the end of file but not require block allocation
|
|
*/
|
|
static int ext4_da_should_update_i_disksize(struct page *page,
|
|
unsigned long offset)
|
|
{
|
|
struct buffer_head *bh;
|
|
struct inode *inode = page->mapping->host;
|
|
unsigned int idx;
|
|
int i;
|
|
|
|
bh = page_buffers(page);
|
|
idx = offset >> inode->i_blkbits;
|
|
|
|
for (i = 0; i < idx; i++)
|
|
bh = bh->b_this_page;
|
|
|
|
if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int ext4_da_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
int ret = 0, ret2;
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
loff_t new_i_size;
|
|
unsigned long start, end;
|
|
int write_mode = (int)(unsigned long)fsdata;
|
|
|
|
if (write_mode == FALL_BACK_TO_NONDELALLOC) {
|
|
switch (ext4_inode_journal_mode(inode)) {
|
|
case EXT4_INODE_ORDERED_DATA_MODE:
|
|
return ext4_ordered_write_end(file, mapping, pos,
|
|
len, copied, page, fsdata);
|
|
case EXT4_INODE_WRITEBACK_DATA_MODE:
|
|
return ext4_writeback_write_end(file, mapping, pos,
|
|
len, copied, page, fsdata);
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
trace_ext4_da_write_end(inode, pos, len, copied);
|
|
start = pos & (PAGE_CACHE_SIZE - 1);
|
|
end = start + copied - 1;
|
|
|
|
/*
|
|
* generic_write_end() will run mark_inode_dirty() if i_size
|
|
* changes. So let's piggyback the i_disksize mark_inode_dirty
|
|
* into that.
|
|
*/
|
|
new_i_size = pos + copied;
|
|
if (copied && new_i_size > EXT4_I(inode)->i_disksize) {
|
|
if (ext4_has_inline_data(inode) ||
|
|
ext4_da_should_update_i_disksize(page, end)) {
|
|
down_write(&EXT4_I(inode)->i_data_sem);
|
|
if (new_i_size > EXT4_I(inode)->i_disksize)
|
|
EXT4_I(inode)->i_disksize = new_i_size;
|
|
up_write(&EXT4_I(inode)->i_data_sem);
|
|
/* We need to mark inode dirty even if
|
|
* new_i_size is less that inode->i_size
|
|
* bu greater than i_disksize.(hint delalloc)
|
|
*/
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
}
|
|
}
|
|
|
|
if (write_mode != CONVERT_INLINE_DATA &&
|
|
ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) &&
|
|
ext4_has_inline_data(inode))
|
|
ret2 = ext4_da_write_inline_data_end(inode, pos, len, copied,
|
|
page);
|
|
else
|
|
ret2 = generic_write_end(file, mapping, pos, len, copied,
|
|
page, fsdata);
|
|
|
|
copied = ret2;
|
|
if (ret2 < 0)
|
|
ret = ret2;
|
|
ret2 = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = ret2;
|
|
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
static void ext4_da_invalidatepage(struct page *page, unsigned long offset)
|
|
{
|
|
/*
|
|
* Drop reserved blocks
|
|
*/
|
|
BUG_ON(!PageLocked(page));
|
|
if (!page_has_buffers(page))
|
|
goto out;
|
|
|
|
ext4_da_page_release_reservation(page, offset);
|
|
|
|
out:
|
|
ext4_invalidatepage(page, offset);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Force all delayed allocation blocks to be allocated for a given inode.
|
|
*/
|
|
int ext4_alloc_da_blocks(struct inode *inode)
|
|
{
|
|
trace_ext4_alloc_da_blocks(inode);
|
|
|
|
if (!EXT4_I(inode)->i_reserved_data_blocks &&
|
|
!EXT4_I(inode)->i_reserved_meta_blocks)
|
|
return 0;
|
|
|
|
/*
|
|
* We do something simple for now. The filemap_flush() will
|
|
* also start triggering a write of the data blocks, which is
|
|
* not strictly speaking necessary (and for users of
|
|
* laptop_mode, not even desirable). However, to do otherwise
|
|
* would require replicating code paths in:
|
|
*
|
|
* ext4_da_writepages() ->
|
|
* write_cache_pages() ---> (via passed in callback function)
|
|
* __mpage_da_writepage() -->
|
|
* mpage_add_bh_to_extent()
|
|
* mpage_da_map_blocks()
|
|
*
|
|
* The problem is that write_cache_pages(), located in
|
|
* mm/page-writeback.c, marks pages clean in preparation for
|
|
* doing I/O, which is not desirable if we're not planning on
|
|
* doing I/O at all.
|
|
*
|
|
* We could call write_cache_pages(), and then redirty all of
|
|
* the pages by calling redirty_page_for_writepage() but that
|
|
* would be ugly in the extreme. So instead we would need to
|
|
* replicate parts of the code in the above functions,
|
|
* simplifying them because we wouldn't actually intend to
|
|
* write out the pages, but rather only collect contiguous
|
|
* logical block extents, call the multi-block allocator, and
|
|
* then update the buffer heads with the block allocations.
|
|
*
|
|
* For now, though, we'll cheat by calling filemap_flush(),
|
|
* which will map the blocks, and start the I/O, but not
|
|
* actually wait for the I/O to complete.
|
|
*/
|
|
return filemap_flush(inode->i_mapping);
|
|
}
|
|
|
|
/*
|
|
* bmap() is special. It gets used by applications such as lilo and by
|
|
* the swapper to find the on-disk block of a specific piece of data.
|
|
*
|
|
* Naturally, this is dangerous if the block concerned is still in the
|
|
* journal. If somebody makes a swapfile on an ext4 data-journaling
|
|
* filesystem and enables swap, then they may get a nasty shock when the
|
|
* data getting swapped to that swapfile suddenly gets overwritten by
|
|
* the original zero's written out previously to the journal and
|
|
* awaiting writeback in the kernel's buffer cache.
|
|
*
|
|
* So, if we see any bmap calls here on a modified, data-journaled file,
|
|
* take extra steps to flush any blocks which might be in the cache.
|
|
*/
|
|
static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
journal_t *journal;
|
|
int err;
|
|
|
|
/*
|
|
* We can get here for an inline file via the FIBMAP ioctl
|
|
*/
|
|
if (ext4_has_inline_data(inode))
|
|
return 0;
|
|
|
|
if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) &&
|
|
test_opt(inode->i_sb, DELALLOC)) {
|
|
/*
|
|
* With delalloc we want to sync the file
|
|
* so that we can make sure we allocate
|
|
* blocks for file
|
|
*/
|
|
filemap_write_and_wait(mapping);
|
|
}
|
|
|
|
if (EXT4_JOURNAL(inode) &&
|
|
ext4_test_inode_state(inode, EXT4_STATE_JDATA)) {
|
|
/*
|
|
* This is a REALLY heavyweight approach, but the use of
|
|
* bmap on dirty files is expected to be extremely rare:
|
|
* only if we run lilo or swapon on a freshly made file
|
|
* do we expect this to happen.
|
|
*
|
|
* (bmap requires CAP_SYS_RAWIO so this does not
|
|
* represent an unprivileged user DOS attack --- we'd be
|
|
* in trouble if mortal users could trigger this path at
|
|
* will.)
|
|
*
|
|
* NB. EXT4_STATE_JDATA is not set on files other than
|
|
* regular files. If somebody wants to bmap a directory
|
|
* or symlink and gets confused because the buffer
|
|
* hasn't yet been flushed to disk, they deserve
|
|
* everything they get.
|
|
*/
|
|
|
|
ext4_clear_inode_state(inode, EXT4_STATE_JDATA);
|
|
journal = EXT4_JOURNAL(inode);
|
|
jbd2_journal_lock_updates(journal);
|
|
err = jbd2_journal_flush(journal);
|
|
jbd2_journal_unlock_updates(journal);
|
|
|
|
if (err)
|
|
return 0;
|
|
}
|
|
|
|
return generic_block_bmap(mapping, block, ext4_get_block);
|
|
}
|
|
|
|
static int ext4_readpage(struct file *file, struct page *page)
|
|
{
|
|
int ret = -EAGAIN;
|
|
struct inode *inode = page->mapping->host;
|
|
|
|
trace_ext4_readpage(page);
|
|
|
|
if (ext4_has_inline_data(inode))
|
|
ret = ext4_readpage_inline(inode, page);
|
|
|
|
if (ret == -EAGAIN)
|
|
return mpage_readpage(page, ext4_get_block);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
ext4_readpages(struct file *file, struct address_space *mapping,
|
|
struct list_head *pages, unsigned nr_pages)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
|
|
/* If the file has inline data, no need to do readpages. */
|
|
if (ext4_has_inline_data(inode))
|
|
return 0;
|
|
|
|
return mpage_readpages(mapping, pages, nr_pages, ext4_get_block);
|
|
}
|
|
|
|
static void ext4_invalidatepage_free_endio(struct page *page, unsigned long offset)
|
|
{
|
|
struct buffer_head *head, *bh;
|
|
unsigned int curr_off = 0;
|
|
|
|
if (!page_has_buffers(page))
|
|
return;
|
|
head = bh = page_buffers(page);
|
|
do {
|
|
if (offset <= curr_off && test_clear_buffer_uninit(bh)
|
|
&& bh->b_private) {
|
|
ext4_free_io_end(bh->b_private);
|
|
bh->b_private = NULL;
|
|
bh->b_end_io = NULL;
|
|
}
|
|
curr_off = curr_off + bh->b_size;
|
|
bh = bh->b_this_page;
|
|
} while (bh != head);
|
|
}
|
|
|
|
static void ext4_invalidatepage(struct page *page, unsigned long offset)
|
|
{
|
|
trace_ext4_invalidatepage(page, offset);
|
|
|
|
/*
|
|
* free any io_end structure allocated for buffers to be discarded
|
|
*/
|
|
if (ext4_should_dioread_nolock(page->mapping->host))
|
|
ext4_invalidatepage_free_endio(page, offset);
|
|
|
|
/* No journalling happens on data buffers when this function is used */
|
|
WARN_ON(page_has_buffers(page) && buffer_jbd(page_buffers(page)));
|
|
|
|
block_invalidatepage(page, offset);
|
|
}
|
|
|
|
static int __ext4_journalled_invalidatepage(struct page *page,
|
|
unsigned long offset)
|
|
{
|
|
journal_t *journal = EXT4_JOURNAL(page->mapping->host);
|
|
|
|
trace_ext4_journalled_invalidatepage(page, offset);
|
|
|
|
/*
|
|
* If it's a full truncate we just forget about the pending dirtying
|
|
*/
|
|
if (offset == 0)
|
|
ClearPageChecked(page);
|
|
|
|
return jbd2_journal_invalidatepage(journal, page, offset);
|
|
}
|
|
|
|
/* Wrapper for aops... */
|
|
static void ext4_journalled_invalidatepage(struct page *page,
|
|
unsigned long offset)
|
|
{
|
|
WARN_ON(__ext4_journalled_invalidatepage(page, offset) < 0);
|
|
}
|
|
|
|
static int ext4_releasepage(struct page *page, gfp_t wait)
|
|
{
|
|
journal_t *journal = EXT4_JOURNAL(page->mapping->host);
|
|
|
|
trace_ext4_releasepage(page);
|
|
|
|
WARN_ON(PageChecked(page));
|
|
if (!page_has_buffers(page))
|
|
return 0;
|
|
if (journal)
|
|
return jbd2_journal_try_to_free_buffers(journal, page, wait);
|
|
else
|
|
return try_to_free_buffers(page);
|
|
}
|
|
|
|
/*
|
|
* ext4_get_block used when preparing for a DIO write or buffer write.
|
|
* We allocate an uinitialized extent if blocks haven't been allocated.
|
|
* The extent will be converted to initialized after the IO is complete.
|
|
*/
|
|
int ext4_get_block_write(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create)
|
|
{
|
|
ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
|
|
inode->i_ino, create);
|
|
return _ext4_get_block(inode, iblock, bh_result,
|
|
EXT4_GET_BLOCKS_IO_CREATE_EXT);
|
|
}
|
|
|
|
static int ext4_get_block_write_nolock(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create)
|
|
{
|
|
ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
|
|
inode->i_ino, create);
|
|
return _ext4_get_block(inode, iblock, bh_result,
|
|
EXT4_GET_BLOCKS_NO_LOCK);
|
|
}
|
|
|
|
static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
|
|
ssize_t size, void *private, int ret,
|
|
bool is_async)
|
|
{
|
|
struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
|
|
ext4_io_end_t *io_end = iocb->private;
|
|
|
|
/* if not async direct IO or dio with 0 bytes write, just return */
|
|
if (!io_end || !size)
|
|
goto out;
|
|
|
|
ext_debug("ext4_end_io_dio(): io_end 0x%p "
|
|
"for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
|
|
iocb->private, io_end->inode->i_ino, iocb, offset,
|
|
size);
|
|
|
|
iocb->private = NULL;
|
|
|
|
/* if not aio dio with unwritten extents, just free io and return */
|
|
if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
|
|
ext4_free_io_end(io_end);
|
|
out:
|
|
if (is_async)
|
|
aio_complete(iocb, ret, 0);
|
|
inode_dio_done(inode);
|
|
return;
|
|
}
|
|
|
|
io_end->offset = offset;
|
|
io_end->size = size;
|
|
if (is_async) {
|
|
io_end->iocb = iocb;
|
|
io_end->result = ret;
|
|
}
|
|
|
|
ext4_add_complete_io(io_end);
|
|
}
|
|
|
|
static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate)
|
|
{
|
|
ext4_io_end_t *io_end = bh->b_private;
|
|
struct inode *inode;
|
|
|
|
if (!test_clear_buffer_uninit(bh) || !io_end)
|
|
goto out;
|
|
|
|
if (!(io_end->inode->i_sb->s_flags & MS_ACTIVE)) {
|
|
ext4_msg(io_end->inode->i_sb, KERN_INFO,
|
|
"sb umounted, discard end_io request for inode %lu",
|
|
io_end->inode->i_ino);
|
|
ext4_free_io_end(io_end);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* It may be over-defensive here to check EXT4_IO_END_UNWRITTEN now,
|
|
* but being more careful is always safe for the future change.
|
|
*/
|
|
inode = io_end->inode;
|
|
ext4_set_io_unwritten_flag(inode, io_end);
|
|
ext4_add_complete_io(io_end);
|
|
out:
|
|
bh->b_private = NULL;
|
|
bh->b_end_io = NULL;
|
|
clear_buffer_uninit(bh);
|
|
end_buffer_async_write(bh, uptodate);
|
|
}
|
|
|
|
static int ext4_set_bh_endio(struct buffer_head *bh, struct inode *inode)
|
|
{
|
|
ext4_io_end_t *io_end;
|
|
struct page *page = bh->b_page;
|
|
loff_t offset = (sector_t)page->index << PAGE_CACHE_SHIFT;
|
|
size_t size = bh->b_size;
|
|
|
|
retry:
|
|
io_end = ext4_init_io_end(inode, GFP_ATOMIC);
|
|
if (!io_end) {
|
|
pr_warn_ratelimited("%s: allocation fail\n", __func__);
|
|
schedule();
|
|
goto retry;
|
|
}
|
|
io_end->offset = offset;
|
|
io_end->size = size;
|
|
/*
|
|
* We need to hold a reference to the page to make sure it
|
|
* doesn't get evicted before ext4_end_io_work() has a chance
|
|
* to convert the extent from written to unwritten.
|
|
*/
|
|
io_end->page = page;
|
|
get_page(io_end->page);
|
|
|
|
bh->b_private = io_end;
|
|
bh->b_end_io = ext4_end_io_buffer_write;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* For ext4 extent files, ext4 will do direct-io write to holes,
|
|
* preallocated extents, and those write extend the file, no need to
|
|
* fall back to buffered IO.
|
|
*
|
|
* For holes, we fallocate those blocks, mark them as uninitialized
|
|
* If those blocks were preallocated, we mark sure they are split, but
|
|
* still keep the range to write as uninitialized.
|
|
*
|
|
* The unwritten extents will be converted to written when DIO is completed.
|
|
* For async direct IO, since the IO may still pending when return, we
|
|
* set up an end_io call back function, which will do the conversion
|
|
* when async direct IO completed.
|
|
*
|
|
* If the O_DIRECT write will extend the file then add this inode to the
|
|
* orphan list. So recovery will truncate it back to the original size
|
|
* if the machine crashes during the write.
|
|
*
|
|
*/
|
|
static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
|
|
const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file->f_mapping->host;
|
|
ssize_t ret;
|
|
size_t count = iov_length(iov, nr_segs);
|
|
int overwrite = 0;
|
|
get_block_t *get_block_func = NULL;
|
|
int dio_flags = 0;
|
|
loff_t final_size = offset + count;
|
|
|
|
/* Use the old path for reads and writes beyond i_size. */
|
|
if (rw != WRITE || final_size > inode->i_size)
|
|
return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
|
|
|
|
BUG_ON(iocb->private == NULL);
|
|
|
|
/* If we do a overwrite dio, i_mutex locking can be released */
|
|
overwrite = *((int *)iocb->private);
|
|
|
|
if (overwrite) {
|
|
atomic_inc(&inode->i_dio_count);
|
|
down_read(&EXT4_I(inode)->i_data_sem);
|
|
mutex_unlock(&inode->i_mutex);
|
|
}
|
|
|
|
/*
|
|
* We could direct write to holes and fallocate.
|
|
*
|
|
* Allocated blocks to fill the hole are marked as
|
|
* uninitialized to prevent parallel buffered read to expose
|
|
* the stale data before DIO complete the data IO.
|
|
*
|
|
* As to previously fallocated extents, ext4 get_block will
|
|
* just simply mark the buffer mapped but still keep the
|
|
* extents uninitialized.
|
|
*
|
|
* For non AIO case, we will convert those unwritten extents
|
|
* to written after return back from blockdev_direct_IO.
|
|
*
|
|
* For async DIO, the conversion needs to be deferred when the
|
|
* IO is completed. The ext4 end_io callback function will be
|
|
* called to take care of the conversion work. Here for async
|
|
* case, we allocate an io_end structure to hook to the iocb.
|
|
*/
|
|
iocb->private = NULL;
|
|
ext4_inode_aio_set(inode, NULL);
|
|
if (!is_sync_kiocb(iocb)) {
|
|
ext4_io_end_t *io_end = ext4_init_io_end(inode, GFP_NOFS);
|
|
if (!io_end) {
|
|
ret = -ENOMEM;
|
|
goto retake_lock;
|
|
}
|
|
io_end->flag |= EXT4_IO_END_DIRECT;
|
|
iocb->private = io_end;
|
|
/*
|
|
* we save the io structure for current async direct
|
|
* IO, so that later ext4_map_blocks() could flag the
|
|
* io structure whether there is a unwritten extents
|
|
* needs to be converted when IO is completed.
|
|
*/
|
|
ext4_inode_aio_set(inode, io_end);
|
|
}
|
|
|
|
if (overwrite) {
|
|
get_block_func = ext4_get_block_write_nolock;
|
|
} else {
|
|
get_block_func = ext4_get_block_write;
|
|
dio_flags = DIO_LOCKING;
|
|
}
|
|
ret = __blockdev_direct_IO(rw, iocb, inode,
|
|
inode->i_sb->s_bdev, iov,
|
|
offset, nr_segs,
|
|
get_block_func,
|
|
ext4_end_io_dio,
|
|
NULL,
|
|
dio_flags);
|
|
|
|
if (iocb->private)
|
|
ext4_inode_aio_set(inode, NULL);
|
|
/*
|
|
* The io_end structure takes a reference to the inode, that
|
|
* structure needs to be destroyed and the reference to the
|
|
* inode need to be dropped, when IO is complete, even with 0
|
|
* byte write, or failed.
|
|
*
|
|
* In the successful AIO DIO case, the io_end structure will
|
|
* be destroyed and the reference to the inode will be dropped
|
|
* after the end_io call back function is called.
|
|
*
|
|
* In the case there is 0 byte write, or error case, since VFS
|
|
* direct IO won't invoke the end_io call back function, we
|
|
* need to free the end_io structure here.
|
|
*/
|
|
if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) {
|
|
ext4_free_io_end(iocb->private);
|
|
iocb->private = NULL;
|
|
} else if (ret > 0 && !overwrite && ext4_test_inode_state(inode,
|
|
EXT4_STATE_DIO_UNWRITTEN)) {
|
|
int err;
|
|
/*
|
|
* for non AIO case, since the IO is already
|
|
* completed, we could do the conversion right here
|
|
*/
|
|
err = ext4_convert_unwritten_extents(inode,
|
|
offset, ret);
|
|
if (err < 0)
|
|
ret = err;
|
|
ext4_clear_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
|
|
}
|
|
|
|
retake_lock:
|
|
/* take i_mutex locking again if we do a ovewrite dio */
|
|
if (overwrite) {
|
|
inode_dio_done(inode);
|
|
up_read(&EXT4_I(inode)->i_data_sem);
|
|
mutex_lock(&inode->i_mutex);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
|
|
const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file->f_mapping->host;
|
|
ssize_t ret;
|
|
|
|
/*
|
|
* If we are doing data journalling we don't support O_DIRECT
|
|
*/
|
|
if (ext4_should_journal_data(inode))
|
|
return 0;
|
|
|
|
/* Let buffer I/O handle the inline data case. */
|
|
if (ext4_has_inline_data(inode))
|
|
return 0;
|
|
|
|
trace_ext4_direct_IO_enter(inode, offset, iov_length(iov, nr_segs), rw);
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
ret = ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
|
|
else
|
|
ret = ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
|
|
trace_ext4_direct_IO_exit(inode, offset,
|
|
iov_length(iov, nr_segs), rw, ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Pages can be marked dirty completely asynchronously from ext4's journalling
|
|
* activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
|
|
* much here because ->set_page_dirty is called under VFS locks. The page is
|
|
* not necessarily locked.
|
|
*
|
|
* We cannot just dirty the page and leave attached buffers clean, because the
|
|
* buffers' dirty state is "definitive". We cannot just set the buffers dirty
|
|
* or jbddirty because all the journalling code will explode.
|
|
*
|
|
* So what we do is to mark the page "pending dirty" and next time writepage
|
|
* is called, propagate that into the buffers appropriately.
|
|
*/
|
|
static int ext4_journalled_set_page_dirty(struct page *page)
|
|
{
|
|
SetPageChecked(page);
|
|
return __set_page_dirty_nobuffers(page);
|
|
}
|
|
|
|
static const struct address_space_operations ext4_ordered_aops = {
|
|
.readpage = ext4_readpage,
|
|
.readpages = ext4_readpages,
|
|
.writepage = ext4_writepage,
|
|
.write_begin = ext4_write_begin,
|
|
.write_end = ext4_ordered_write_end,
|
|
.bmap = ext4_bmap,
|
|
.invalidatepage = ext4_invalidatepage,
|
|
.releasepage = ext4_releasepage,
|
|
.direct_IO = ext4_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
static const struct address_space_operations ext4_writeback_aops = {
|
|
.readpage = ext4_readpage,
|
|
.readpages = ext4_readpages,
|
|
.writepage = ext4_writepage,
|
|
.write_begin = ext4_write_begin,
|
|
.write_end = ext4_writeback_write_end,
|
|
.bmap = ext4_bmap,
|
|
.invalidatepage = ext4_invalidatepage,
|
|
.releasepage = ext4_releasepage,
|
|
.direct_IO = ext4_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
static const struct address_space_operations ext4_journalled_aops = {
|
|
.readpage = ext4_readpage,
|
|
.readpages = ext4_readpages,
|
|
.writepage = ext4_writepage,
|
|
.write_begin = ext4_write_begin,
|
|
.write_end = ext4_journalled_write_end,
|
|
.set_page_dirty = ext4_journalled_set_page_dirty,
|
|
.bmap = ext4_bmap,
|
|
.invalidatepage = ext4_journalled_invalidatepage,
|
|
.releasepage = ext4_releasepage,
|
|
.direct_IO = ext4_direct_IO,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
static const struct address_space_operations ext4_da_aops = {
|
|
.readpage = ext4_readpage,
|
|
.readpages = ext4_readpages,
|
|
.writepage = ext4_writepage,
|
|
.writepages = ext4_da_writepages,
|
|
.write_begin = ext4_da_write_begin,
|
|
.write_end = ext4_da_write_end,
|
|
.bmap = ext4_bmap,
|
|
.invalidatepage = ext4_da_invalidatepage,
|
|
.releasepage = ext4_releasepage,
|
|
.direct_IO = ext4_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
void ext4_set_aops(struct inode *inode)
|
|
{
|
|
switch (ext4_inode_journal_mode(inode)) {
|
|
case EXT4_INODE_ORDERED_DATA_MODE:
|
|
if (test_opt(inode->i_sb, DELALLOC))
|
|
inode->i_mapping->a_ops = &ext4_da_aops;
|
|
else
|
|
inode->i_mapping->a_ops = &ext4_ordered_aops;
|
|
break;
|
|
case EXT4_INODE_WRITEBACK_DATA_MODE:
|
|
if (test_opt(inode->i_sb, DELALLOC))
|
|
inode->i_mapping->a_ops = &ext4_da_aops;
|
|
else
|
|
inode->i_mapping->a_ops = &ext4_writeback_aops;
|
|
break;
|
|
case EXT4_INODE_JOURNAL_DATA_MODE:
|
|
inode->i_mapping->a_ops = &ext4_journalled_aops;
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* ext4_discard_partial_page_buffers()
|
|
* Wrapper function for ext4_discard_partial_page_buffers_no_lock.
|
|
* This function finds and locks the page containing the offset
|
|
* "from" and passes it to ext4_discard_partial_page_buffers_no_lock.
|
|
* Calling functions that already have the page locked should call
|
|
* ext4_discard_partial_page_buffers_no_lock directly.
|
|
*/
|
|
int ext4_discard_partial_page_buffers(handle_t *handle,
|
|
struct address_space *mapping, loff_t from,
|
|
loff_t length, int flags)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
struct page *page;
|
|
int err = 0;
|
|
|
|
page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT,
|
|
mapping_gfp_mask(mapping) & ~__GFP_FS);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
err = ext4_discard_partial_page_buffers_no_lock(handle, inode, page,
|
|
from, length, flags);
|
|
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_discard_partial_page_buffers_no_lock()
|
|
* Zeros a page range of length 'length' starting from offset 'from'.
|
|
* Buffer heads that correspond to the block aligned regions of the
|
|
* zeroed range will be unmapped. Unblock aligned regions
|
|
* will have the corresponding buffer head mapped if needed so that
|
|
* that region of the page can be updated with the partial zero out.
|
|
*
|
|
* This function assumes that the page has already been locked. The
|
|
* The range to be discarded must be contained with in the given page.
|
|
* If the specified range exceeds the end of the page it will be shortened
|
|
* to the end of the page that corresponds to 'from'. This function is
|
|
* appropriate for updating a page and it buffer heads to be unmapped and
|
|
* zeroed for blocks that have been either released, or are going to be
|
|
* released.
|
|
*
|
|
* handle: The journal handle
|
|
* inode: The files inode
|
|
* page: A locked page that contains the offset "from"
|
|
* from: The starting byte offset (from the beginning of the file)
|
|
* to begin discarding
|
|
* len: The length of bytes to discard
|
|
* flags: Optional flags that may be used:
|
|
*
|
|
* EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED
|
|
* Only zero the regions of the page whose buffer heads
|
|
* have already been unmapped. This flag is appropriate
|
|
* for updating the contents of a page whose blocks may
|
|
* have already been released, and we only want to zero
|
|
* out the regions that correspond to those released blocks.
|
|
*
|
|
* Returns zero on success or negative on failure.
|
|
*/
|
|
static int ext4_discard_partial_page_buffers_no_lock(handle_t *handle,
|
|
struct inode *inode, struct page *page, loff_t from,
|
|
loff_t length, int flags)
|
|
{
|
|
ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
|
|
unsigned int offset = from & (PAGE_CACHE_SIZE-1);
|
|
unsigned int blocksize, max, pos;
|
|
ext4_lblk_t iblock;
|
|
struct buffer_head *bh;
|
|
int err = 0;
|
|
|
|
blocksize = inode->i_sb->s_blocksize;
|
|
max = PAGE_CACHE_SIZE - offset;
|
|
|
|
if (index != page->index)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* correct length if it does not fall between
|
|
* 'from' and the end of the page
|
|
*/
|
|
if (length > max || length < 0)
|
|
length = max;
|
|
|
|
iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
|
|
|
|
if (!page_has_buffers(page))
|
|
create_empty_buffers(page, blocksize, 0);
|
|
|
|
/* Find the buffer that contains "offset" */
|
|
bh = page_buffers(page);
|
|
pos = blocksize;
|
|
while (offset >= pos) {
|
|
bh = bh->b_this_page;
|
|
iblock++;
|
|
pos += blocksize;
|
|
}
|
|
|
|
pos = offset;
|
|
while (pos < offset + length) {
|
|
unsigned int end_of_block, range_to_discard;
|
|
|
|
err = 0;
|
|
|
|
/* The length of space left to zero and unmap */
|
|
range_to_discard = offset + length - pos;
|
|
|
|
/* The length of space until the end of the block */
|
|
end_of_block = blocksize - (pos & (blocksize-1));
|
|
|
|
/*
|
|
* Do not unmap or zero past end of block
|
|
* for this buffer head
|
|
*/
|
|
if (range_to_discard > end_of_block)
|
|
range_to_discard = end_of_block;
|
|
|
|
|
|
/*
|
|
* Skip this buffer head if we are only zeroing unampped
|
|
* regions of the page
|
|
*/
|
|
if (flags & EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED &&
|
|
buffer_mapped(bh))
|
|
goto next;
|
|
|
|
/* If the range is block aligned, unmap */
|
|
if (range_to_discard == blocksize) {
|
|
clear_buffer_dirty(bh);
|
|
bh->b_bdev = NULL;
|
|
clear_buffer_mapped(bh);
|
|
clear_buffer_req(bh);
|
|
clear_buffer_new(bh);
|
|
clear_buffer_delay(bh);
|
|
clear_buffer_unwritten(bh);
|
|
clear_buffer_uptodate(bh);
|
|
zero_user(page, pos, range_to_discard);
|
|
BUFFER_TRACE(bh, "Buffer discarded");
|
|
goto next;
|
|
}
|
|
|
|
/*
|
|
* If this block is not completely contained in the range
|
|
* to be discarded, then it is not going to be released. Because
|
|
* we need to keep this block, we need to make sure this part
|
|
* of the page is uptodate before we modify it by writeing
|
|
* partial zeros on it.
|
|
*/
|
|
if (!buffer_mapped(bh)) {
|
|
/*
|
|
* Buffer head must be mapped before we can read
|
|
* from the block
|
|
*/
|
|
BUFFER_TRACE(bh, "unmapped");
|
|
ext4_get_block(inode, iblock, bh, 0);
|
|
/* unmapped? It's a hole - nothing to do */
|
|
if (!buffer_mapped(bh)) {
|
|
BUFFER_TRACE(bh, "still unmapped");
|
|
goto next;
|
|
}
|
|
}
|
|
|
|
/* Ok, it's mapped. Make sure it's up-to-date */
|
|
if (PageUptodate(page))
|
|
set_buffer_uptodate(bh);
|
|
|
|
if (!buffer_uptodate(bh)) {
|
|
err = -EIO;
|
|
ll_rw_block(READ, 1, &bh);
|
|
wait_on_buffer(bh);
|
|
/* Uhhuh. Read error. Complain and punt.*/
|
|
if (!buffer_uptodate(bh))
|
|
goto next;
|
|
}
|
|
|
|
if (ext4_should_journal_data(inode)) {
|
|
BUFFER_TRACE(bh, "get write access");
|
|
err = ext4_journal_get_write_access(handle, bh);
|
|
if (err)
|
|
goto next;
|
|
}
|
|
|
|
zero_user(page, pos, range_to_discard);
|
|
|
|
err = 0;
|
|
if (ext4_should_journal_data(inode)) {
|
|
err = ext4_handle_dirty_metadata(handle, inode, bh);
|
|
} else
|
|
mark_buffer_dirty(bh);
|
|
|
|
BUFFER_TRACE(bh, "Partial buffer zeroed");
|
|
next:
|
|
bh = bh->b_this_page;
|
|
iblock++;
|
|
pos += range_to_discard;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
int ext4_can_truncate(struct inode *inode)
|
|
{
|
|
if (S_ISREG(inode->i_mode))
|
|
return 1;
|
|
if (S_ISDIR(inode->i_mode))
|
|
return 1;
|
|
if (S_ISLNK(inode->i_mode))
|
|
return !ext4_inode_is_fast_symlink(inode);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ext4_punch_hole: punches a hole in a file by releaseing the blocks
|
|
* associated with the given offset and length
|
|
*
|
|
* @inode: File inode
|
|
* @offset: The offset where the hole will begin
|
|
* @len: The length of the hole
|
|
*
|
|
* Returns: 0 on success or negative on failure
|
|
*/
|
|
|
|
int ext4_punch_hole(struct file *file, loff_t offset, loff_t length)
|
|
{
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
if (!S_ISREG(inode->i_mode))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
/* TODO: Add support for non extent hole punching */
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
if (EXT4_SB(inode->i_sb)->s_cluster_ratio > 1) {
|
|
/* TODO: Add support for bigalloc file systems */
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
return ext4_ext_punch_hole(file, offset, length);
|
|
}
|
|
|
|
/*
|
|
* ext4_truncate()
|
|
*
|
|
* We block out ext4_get_block() block instantiations across the entire
|
|
* transaction, and VFS/VM ensures that ext4_truncate() cannot run
|
|
* simultaneously on behalf of the same inode.
|
|
*
|
|
* As we work through the truncate and commit bits of it to the journal there
|
|
* is one core, guiding principle: the file's tree must always be consistent on
|
|
* disk. We must be able to restart the truncate after a crash.
|
|
*
|
|
* The file's tree may be transiently inconsistent in memory (although it
|
|
* probably isn't), but whenever we close off and commit a journal transaction,
|
|
* the contents of (the filesystem + the journal) must be consistent and
|
|
* restartable. It's pretty simple, really: bottom up, right to left (although
|
|
* left-to-right works OK too).
|
|
*
|
|
* Note that at recovery time, journal replay occurs *before* the restart of
|
|
* truncate against the orphan inode list.
|
|
*
|
|
* The committed inode has the new, desired i_size (which is the same as
|
|
* i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
|
|
* that this inode's truncate did not complete and it will again call
|
|
* ext4_truncate() to have another go. So there will be instantiated blocks
|
|
* to the right of the truncation point in a crashed ext4 filesystem. But
|
|
* that's fine - as long as they are linked from the inode, the post-crash
|
|
* ext4_truncate() run will find them and release them.
|
|
*/
|
|
void ext4_truncate(struct inode *inode)
|
|
{
|
|
trace_ext4_truncate_enter(inode);
|
|
|
|
if (!ext4_can_truncate(inode))
|
|
return;
|
|
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
|
|
|
|
if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
|
|
ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
|
|
|
|
if (ext4_has_inline_data(inode)) {
|
|
int has_inline = 1;
|
|
|
|
ext4_inline_data_truncate(inode, &has_inline);
|
|
if (has_inline)
|
|
return;
|
|
}
|
|
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
ext4_ext_truncate(inode);
|
|
else
|
|
ext4_ind_truncate(inode);
|
|
|
|
trace_ext4_truncate_exit(inode);
|
|
}
|
|
|
|
/*
|
|
* ext4_get_inode_loc returns with an extra refcount against the inode's
|
|
* underlying buffer_head on success. If 'in_mem' is true, we have all
|
|
* data in memory that is needed to recreate the on-disk version of this
|
|
* inode.
|
|
*/
|
|
static int __ext4_get_inode_loc(struct inode *inode,
|
|
struct ext4_iloc *iloc, int in_mem)
|
|
{
|
|
struct ext4_group_desc *gdp;
|
|
struct buffer_head *bh;
|
|
struct super_block *sb = inode->i_sb;
|
|
ext4_fsblk_t block;
|
|
int inodes_per_block, inode_offset;
|
|
|
|
iloc->bh = NULL;
|
|
if (!ext4_valid_inum(sb, inode->i_ino))
|
|
return -EIO;
|
|
|
|
iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb);
|
|
gdp = ext4_get_group_desc(sb, iloc->block_group, NULL);
|
|
if (!gdp)
|
|
return -EIO;
|
|
|
|
/*
|
|
* Figure out the offset within the block group inode table
|
|
*/
|
|
inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
|
|
inode_offset = ((inode->i_ino - 1) %
|
|
EXT4_INODES_PER_GROUP(sb));
|
|
block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block);
|
|
iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb);
|
|
|
|
bh = sb_getblk(sb, block);
|
|
if (!bh) {
|
|
EXT4_ERROR_INODE_BLOCK(inode, block,
|
|
"unable to read itable block");
|
|
return -EIO;
|
|
}
|
|
if (!buffer_uptodate(bh)) {
|
|
lock_buffer(bh);
|
|
|
|
/*
|
|
* If the buffer has the write error flag, we have failed
|
|
* to write out another inode in the same block. In this
|
|
* case, we don't have to read the block because we may
|
|
* read the old inode data successfully.
|
|
*/
|
|
if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
|
|
set_buffer_uptodate(bh);
|
|
|
|
if (buffer_uptodate(bh)) {
|
|
/* someone brought it uptodate while we waited */
|
|
unlock_buffer(bh);
|
|
goto has_buffer;
|
|
}
|
|
|
|
/*
|
|
* If we have all information of the inode in memory and this
|
|
* is the only valid inode in the block, we need not read the
|
|
* block.
|
|
*/
|
|
if (in_mem) {
|
|
struct buffer_head *bitmap_bh;
|
|
int i, start;
|
|
|
|
start = inode_offset & ~(inodes_per_block - 1);
|
|
|
|
/* Is the inode bitmap in cache? */
|
|
bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp));
|
|
if (!bitmap_bh)
|
|
goto make_io;
|
|
|
|
/*
|
|
* If the inode bitmap isn't in cache then the
|
|
* optimisation may end up performing two reads instead
|
|
* of one, so skip it.
|
|
*/
|
|
if (!buffer_uptodate(bitmap_bh)) {
|
|
brelse(bitmap_bh);
|
|
goto make_io;
|
|
}
|
|
for (i = start; i < start + inodes_per_block; i++) {
|
|
if (i == inode_offset)
|
|
continue;
|
|
if (ext4_test_bit(i, bitmap_bh->b_data))
|
|
break;
|
|
}
|
|
brelse(bitmap_bh);
|
|
if (i == start + inodes_per_block) {
|
|
/* all other inodes are free, so skip I/O */
|
|
memset(bh->b_data, 0, bh->b_size);
|
|
set_buffer_uptodate(bh);
|
|
unlock_buffer(bh);
|
|
goto has_buffer;
|
|
}
|
|
}
|
|
|
|
make_io:
|
|
/*
|
|
* If we need to do any I/O, try to pre-readahead extra
|
|
* blocks from the inode table.
|
|
*/
|
|
if (EXT4_SB(sb)->s_inode_readahead_blks) {
|
|
ext4_fsblk_t b, end, table;
|
|
unsigned num;
|
|
|
|
table = ext4_inode_table(sb, gdp);
|
|
/* s_inode_readahead_blks is always a power of 2 */
|
|
b = block & ~(EXT4_SB(sb)->s_inode_readahead_blks-1);
|
|
if (table > b)
|
|
b = table;
|
|
end = b + EXT4_SB(sb)->s_inode_readahead_blks;
|
|
num = EXT4_INODES_PER_GROUP(sb);
|
|
if (ext4_has_group_desc_csum(sb))
|
|
num -= ext4_itable_unused_count(sb, gdp);
|
|
table += num / inodes_per_block;
|
|
if (end > table)
|
|
end = table;
|
|
while (b <= end)
|
|
sb_breadahead(sb, b++);
|
|
}
|
|
|
|
/*
|
|
* There are other valid inodes in the buffer, this inode
|
|
* has in-inode xattrs, or we don't have this inode in memory.
|
|
* Read the block from disk.
|
|
*/
|
|
trace_ext4_load_inode(inode);
|
|
get_bh(bh);
|
|
bh->b_end_io = end_buffer_read_sync;
|
|
submit_bh(READ | REQ_META | REQ_PRIO, bh);
|
|
wait_on_buffer(bh);
|
|
if (!buffer_uptodate(bh)) {
|
|
EXT4_ERROR_INODE_BLOCK(inode, block,
|
|
"unable to read itable block");
|
|
brelse(bh);
|
|
return -EIO;
|
|
}
|
|
}
|
|
has_buffer:
|
|
iloc->bh = bh;
|
|
return 0;
|
|
}
|
|
|
|
int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc)
|
|
{
|
|
/* We have all inode data except xattrs in memory here. */
|
|
return __ext4_get_inode_loc(inode, iloc,
|
|
!ext4_test_inode_state(inode, EXT4_STATE_XATTR));
|
|
}
|
|
|
|
void ext4_set_inode_flags(struct inode *inode)
|
|
{
|
|
unsigned int flags = EXT4_I(inode)->i_flags;
|
|
|
|
inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
|
|
if (flags & EXT4_SYNC_FL)
|
|
inode->i_flags |= S_SYNC;
|
|
if (flags & EXT4_APPEND_FL)
|
|
inode->i_flags |= S_APPEND;
|
|
if (flags & EXT4_IMMUTABLE_FL)
|
|
inode->i_flags |= S_IMMUTABLE;
|
|
if (flags & EXT4_NOATIME_FL)
|
|
inode->i_flags |= S_NOATIME;
|
|
if (flags & EXT4_DIRSYNC_FL)
|
|
inode->i_flags |= S_DIRSYNC;
|
|
}
|
|
|
|
/* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
|
|
void ext4_get_inode_flags(struct ext4_inode_info *ei)
|
|
{
|
|
unsigned int vfs_fl;
|
|
unsigned long old_fl, new_fl;
|
|
|
|
do {
|
|
vfs_fl = ei->vfs_inode.i_flags;
|
|
old_fl = ei->i_flags;
|
|
new_fl = old_fl & ~(EXT4_SYNC_FL|EXT4_APPEND_FL|
|
|
EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|
|
|
EXT4_DIRSYNC_FL);
|
|
if (vfs_fl & S_SYNC)
|
|
new_fl |= EXT4_SYNC_FL;
|
|
if (vfs_fl & S_APPEND)
|
|
new_fl |= EXT4_APPEND_FL;
|
|
if (vfs_fl & S_IMMUTABLE)
|
|
new_fl |= EXT4_IMMUTABLE_FL;
|
|
if (vfs_fl & S_NOATIME)
|
|
new_fl |= EXT4_NOATIME_FL;
|
|
if (vfs_fl & S_DIRSYNC)
|
|
new_fl |= EXT4_DIRSYNC_FL;
|
|
} while (cmpxchg(&ei->i_flags, old_fl, new_fl) != old_fl);
|
|
}
|
|
|
|
static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
blkcnt_t i_blocks ;
|
|
struct inode *inode = &(ei->vfs_inode);
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
|
|
/* we are using combined 48 bit field */
|
|
i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 |
|
|
le32_to_cpu(raw_inode->i_blocks_lo);
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_HUGE_FILE)) {
|
|
/* i_blocks represent file system block size */
|
|
return i_blocks << (inode->i_blkbits - 9);
|
|
} else {
|
|
return i_blocks;
|
|
}
|
|
} else {
|
|
return le32_to_cpu(raw_inode->i_blocks_lo);
|
|
}
|
|
}
|
|
|
|
static inline void ext4_iget_extra_inode(struct inode *inode,
|
|
struct ext4_inode *raw_inode,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
__le32 *magic = (void *)raw_inode +
|
|
EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize;
|
|
if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC)) {
|
|
ext4_set_inode_state(inode, EXT4_STATE_XATTR);
|
|
ext4_find_inline_data_nolock(inode);
|
|
} else
|
|
EXT4_I(inode)->i_inline_off = 0;
|
|
}
|
|
|
|
struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
|
|
{
|
|
struct ext4_iloc iloc;
|
|
struct ext4_inode *raw_inode;
|
|
struct ext4_inode_info *ei;
|
|
struct inode *inode;
|
|
journal_t *journal = EXT4_SB(sb)->s_journal;
|
|
long ret;
|
|
int block;
|
|
uid_t i_uid;
|
|
gid_t i_gid;
|
|
|
|
inode = iget_locked(sb, ino);
|
|
if (!inode)
|
|
return ERR_PTR(-ENOMEM);
|
|
if (!(inode->i_state & I_NEW))
|
|
return inode;
|
|
|
|
ei = EXT4_I(inode);
|
|
iloc.bh = NULL;
|
|
|
|
ret = __ext4_get_inode_loc(inode, &iloc, 0);
|
|
if (ret < 0)
|
|
goto bad_inode;
|
|
raw_inode = ext4_raw_inode(&iloc);
|
|
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
|
|
ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
|
|
if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
|
|
EXT4_INODE_SIZE(inode->i_sb)) {
|
|
EXT4_ERROR_INODE(inode, "bad extra_isize (%u != %u)",
|
|
EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize,
|
|
EXT4_INODE_SIZE(inode->i_sb));
|
|
ret = -EIO;
|
|
goto bad_inode;
|
|
}
|
|
} else
|
|
ei->i_extra_isize = 0;
|
|
|
|
/* Precompute checksum seed for inode metadata */
|
|
if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
__u32 csum;
|
|
__le32 inum = cpu_to_le32(inode->i_ino);
|
|
__le32 gen = raw_inode->i_generation;
|
|
csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&inum,
|
|
sizeof(inum));
|
|
ei->i_csum_seed = ext4_chksum(sbi, csum, (__u8 *)&gen,
|
|
sizeof(gen));
|
|
}
|
|
|
|
if (!ext4_inode_csum_verify(inode, raw_inode, ei)) {
|
|
EXT4_ERROR_INODE(inode, "checksum invalid");
|
|
ret = -EIO;
|
|
goto bad_inode;
|
|
}
|
|
|
|
inode->i_mode = le16_to_cpu(raw_inode->i_mode);
|
|
i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
|
|
i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
|
|
if (!(test_opt(inode->i_sb, NO_UID32))) {
|
|
i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
|
|
i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
|
|
}
|
|
i_uid_write(inode, i_uid);
|
|
i_gid_write(inode, i_gid);
|
|
set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
|
|
|
|
ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
|
|
ei->i_inline_off = 0;
|
|
ei->i_dir_start_lookup = 0;
|
|
ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
|
|
/* We now have enough fields to check if the inode was active or not.
|
|
* This is needed because nfsd might try to access dead inodes
|
|
* the test is that same one that e2fsck uses
|
|
* NeilBrown 1999oct15
|
|
*/
|
|
if (inode->i_nlink == 0) {
|
|
if (inode->i_mode == 0 ||
|
|
!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) {
|
|
/* this inode is deleted */
|
|
ret = -ESTALE;
|
|
goto bad_inode;
|
|
}
|
|
/* The only unlinked inodes we let through here have
|
|
* valid i_mode and are being read by the orphan
|
|
* recovery code: that's fine, we're about to complete
|
|
* the process of deleting those. */
|
|
}
|
|
ei->i_flags = le32_to_cpu(raw_inode->i_flags);
|
|
inode->i_blocks = ext4_inode_blocks(raw_inode, ei);
|
|
ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo);
|
|
if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT))
|
|
ei->i_file_acl |=
|
|
((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32;
|
|
inode->i_size = ext4_isize(raw_inode);
|
|
ei->i_disksize = inode->i_size;
|
|
#ifdef CONFIG_QUOTA
|
|
ei->i_reserved_quota = 0;
|
|
#endif
|
|
inode->i_generation = le32_to_cpu(raw_inode->i_generation);
|
|
ei->i_block_group = iloc.block_group;
|
|
ei->i_last_alloc_group = ~0;
|
|
/*
|
|
* NOTE! The in-memory inode i_data array is in little-endian order
|
|
* even on big-endian machines: we do NOT byteswap the block numbers!
|
|
*/
|
|
for (block = 0; block < EXT4_N_BLOCKS; block++)
|
|
ei->i_data[block] = raw_inode->i_block[block];
|
|
INIT_LIST_HEAD(&ei->i_orphan);
|
|
|
|
/*
|
|
* Set transaction id's of transactions that have to be committed
|
|
* to finish f[data]sync. We set them to currently running transaction
|
|
* as we cannot be sure that the inode or some of its metadata isn't
|
|
* part of the transaction - the inode could have been reclaimed and
|
|
* now it is reread from disk.
|
|
*/
|
|
if (journal) {
|
|
transaction_t *transaction;
|
|
tid_t tid;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_running_transaction)
|
|
transaction = journal->j_running_transaction;
|
|
else
|
|
transaction = journal->j_committing_transaction;
|
|
if (transaction)
|
|
tid = transaction->t_tid;
|
|
else
|
|
tid = journal->j_commit_sequence;
|
|
read_unlock(&journal->j_state_lock);
|
|
ei->i_sync_tid = tid;
|
|
ei->i_datasync_tid = tid;
|
|
}
|
|
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
|
|
if (ei->i_extra_isize == 0) {
|
|
/* The extra space is currently unused. Use it. */
|
|
ei->i_extra_isize = sizeof(struct ext4_inode) -
|
|
EXT4_GOOD_OLD_INODE_SIZE;
|
|
} else {
|
|
ext4_iget_extra_inode(inode, raw_inode, ei);
|
|
}
|
|
}
|
|
|
|
EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode);
|
|
EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode);
|
|
EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode);
|
|
EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode);
|
|
|
|
inode->i_version = le32_to_cpu(raw_inode->i_disk_version);
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
|
|
if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
|
|
inode->i_version |=
|
|
(__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32;
|
|
}
|
|
|
|
ret = 0;
|
|
if (ei->i_file_acl &&
|
|
!ext4_data_block_valid(EXT4_SB(sb), ei->i_file_acl, 1)) {
|
|
EXT4_ERROR_INODE(inode, "bad extended attribute block %llu",
|
|
ei->i_file_acl);
|
|
ret = -EIO;
|
|
goto bad_inode;
|
|
} else if (!ext4_has_inline_data(inode)) {
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
if ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
|
|
(S_ISLNK(inode->i_mode) &&
|
|
!ext4_inode_is_fast_symlink(inode))))
|
|
/* Validate extent which is part of inode */
|
|
ret = ext4_ext_check_inode(inode);
|
|
} else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
|
|
(S_ISLNK(inode->i_mode) &&
|
|
!ext4_inode_is_fast_symlink(inode))) {
|
|
/* Validate block references which are part of inode */
|
|
ret = ext4_ind_check_inode(inode);
|
|
}
|
|
}
|
|
if (ret)
|
|
goto bad_inode;
|
|
|
|
if (S_ISREG(inode->i_mode)) {
|
|
inode->i_op = &ext4_file_inode_operations;
|
|
inode->i_fop = &ext4_file_operations;
|
|
ext4_set_aops(inode);
|
|
} else if (S_ISDIR(inode->i_mode)) {
|
|
inode->i_op = &ext4_dir_inode_operations;
|
|
inode->i_fop = &ext4_dir_operations;
|
|
} else if (S_ISLNK(inode->i_mode)) {
|
|
if (ext4_inode_is_fast_symlink(inode)) {
|
|
inode->i_op = &ext4_fast_symlink_inode_operations;
|
|
nd_terminate_link(ei->i_data, inode->i_size,
|
|
sizeof(ei->i_data) - 1);
|
|
} else {
|
|
inode->i_op = &ext4_symlink_inode_operations;
|
|
ext4_set_aops(inode);
|
|
}
|
|
} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
|
|
S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
|
|
inode->i_op = &ext4_special_inode_operations;
|
|
if (raw_inode->i_block[0])
|
|
init_special_inode(inode, inode->i_mode,
|
|
old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
|
|
else
|
|
init_special_inode(inode, inode->i_mode,
|
|
new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
|
|
} else {
|
|
ret = -EIO;
|
|
EXT4_ERROR_INODE(inode, "bogus i_mode (%o)", inode->i_mode);
|
|
goto bad_inode;
|
|
}
|
|
brelse(iloc.bh);
|
|
ext4_set_inode_flags(inode);
|
|
unlock_new_inode(inode);
|
|
return inode;
|
|
|
|
bad_inode:
|
|
brelse(iloc.bh);
|
|
iget_failed(inode);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
static int ext4_inode_blocks_set(handle_t *handle,
|
|
struct ext4_inode *raw_inode,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
struct inode *inode = &(ei->vfs_inode);
|
|
u64 i_blocks = inode->i_blocks;
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
if (i_blocks <= ~0U) {
|
|
/*
|
|
* i_blocks can be represented in a 32 bit variable
|
|
* as multiple of 512 bytes
|
|
*/
|
|
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
|
|
raw_inode->i_blocks_high = 0;
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
|
|
return 0;
|
|
}
|
|
if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE))
|
|
return -EFBIG;
|
|
|
|
if (i_blocks <= 0xffffffffffffULL) {
|
|
/*
|
|
* i_blocks can be represented in a 48 bit variable
|
|
* as multiple of 512 bytes
|
|
*/
|
|
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
|
|
raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
|
|
} else {
|
|
ext4_set_inode_flag(inode, EXT4_INODE_HUGE_FILE);
|
|
/* i_block is stored in file system block size */
|
|
i_blocks = i_blocks >> (inode->i_blkbits - 9);
|
|
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
|
|
raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Post the struct inode info into an on-disk inode location in the
|
|
* buffer-cache. This gobbles the caller's reference to the
|
|
* buffer_head in the inode location struct.
|
|
*
|
|
* The caller must have write access to iloc->bh.
|
|
*/
|
|
static int ext4_do_update_inode(handle_t *handle,
|
|
struct inode *inode,
|
|
struct ext4_iloc *iloc)
|
|
{
|
|
struct ext4_inode *raw_inode = ext4_raw_inode(iloc);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
struct buffer_head *bh = iloc->bh;
|
|
int err = 0, rc, block;
|
|
int need_datasync = 0;
|
|
uid_t i_uid;
|
|
gid_t i_gid;
|
|
|
|
/* For fields not not tracking in the in-memory inode,
|
|
* initialise them to zero for new inodes. */
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_NEW))
|
|
memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
|
|
|
|
ext4_get_inode_flags(ei);
|
|
raw_inode->i_mode = cpu_to_le16(inode->i_mode);
|
|
i_uid = i_uid_read(inode);
|
|
i_gid = i_gid_read(inode);
|
|
if (!(test_opt(inode->i_sb, NO_UID32))) {
|
|
raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
|
|
raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
|
|
/*
|
|
* Fix up interoperability with old kernels. Otherwise, old inodes get
|
|
* re-used with the upper 16 bits of the uid/gid intact
|
|
*/
|
|
if (!ei->i_dtime) {
|
|
raw_inode->i_uid_high =
|
|
cpu_to_le16(high_16_bits(i_uid));
|
|
raw_inode->i_gid_high =
|
|
cpu_to_le16(high_16_bits(i_gid));
|
|
} else {
|
|
raw_inode->i_uid_high = 0;
|
|
raw_inode->i_gid_high = 0;
|
|
}
|
|
} else {
|
|
raw_inode->i_uid_low = cpu_to_le16(fs_high2lowuid(i_uid));
|
|
raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(i_gid));
|
|
raw_inode->i_uid_high = 0;
|
|
raw_inode->i_gid_high = 0;
|
|
}
|
|
raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
|
|
|
|
EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode);
|
|
EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode);
|
|
EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
|
|
EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode);
|
|
|
|
if (ext4_inode_blocks_set(handle, raw_inode, ei))
|
|
goto out_brelse;
|
|
raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
|
|
raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF);
|
|
if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
|
|
cpu_to_le32(EXT4_OS_HURD))
|
|
raw_inode->i_file_acl_high =
|
|
cpu_to_le16(ei->i_file_acl >> 32);
|
|
raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl);
|
|
if (ei->i_disksize != ext4_isize(raw_inode)) {
|
|
ext4_isize_set(raw_inode, ei->i_disksize);
|
|
need_datasync = 1;
|
|
}
|
|
if (ei->i_disksize > 0x7fffffffULL) {
|
|
struct super_block *sb = inode->i_sb;
|
|
if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_LARGE_FILE) ||
|
|
EXT4_SB(sb)->s_es->s_rev_level ==
|
|
cpu_to_le32(EXT4_GOOD_OLD_REV)) {
|
|
/* If this is the first large file
|
|
* created, add a flag to the superblock.
|
|
*/
|
|
err = ext4_journal_get_write_access(handle,
|
|
EXT4_SB(sb)->s_sbh);
|
|
if (err)
|
|
goto out_brelse;
|
|
ext4_update_dynamic_rev(sb);
|
|
EXT4_SET_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_LARGE_FILE);
|
|
ext4_handle_sync(handle);
|
|
err = ext4_handle_dirty_super(handle, sb);
|
|
}
|
|
}
|
|
raw_inode->i_generation = cpu_to_le32(inode->i_generation);
|
|
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
|
|
if (old_valid_dev(inode->i_rdev)) {
|
|
raw_inode->i_block[0] =
|
|
cpu_to_le32(old_encode_dev(inode->i_rdev));
|
|
raw_inode->i_block[1] = 0;
|
|
} else {
|
|
raw_inode->i_block[0] = 0;
|
|
raw_inode->i_block[1] =
|
|
cpu_to_le32(new_encode_dev(inode->i_rdev));
|
|
raw_inode->i_block[2] = 0;
|
|
}
|
|
} else if (!ext4_has_inline_data(inode)) {
|
|
for (block = 0; block < EXT4_N_BLOCKS; block++)
|
|
raw_inode->i_block[block] = ei->i_data[block];
|
|
}
|
|
|
|
raw_inode->i_disk_version = cpu_to_le32(inode->i_version);
|
|
if (ei->i_extra_isize) {
|
|
if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
|
|
raw_inode->i_version_hi =
|
|
cpu_to_le32(inode->i_version >> 32);
|
|
raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
|
|
}
|
|
|
|
ext4_inode_csum_set(inode, raw_inode, ei);
|
|
|
|
BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
|
|
rc = ext4_handle_dirty_metadata(handle, NULL, bh);
|
|
if (!err)
|
|
err = rc;
|
|
ext4_clear_inode_state(inode, EXT4_STATE_NEW);
|
|
|
|
ext4_update_inode_fsync_trans(handle, inode, need_datasync);
|
|
out_brelse:
|
|
brelse(bh);
|
|
ext4_std_error(inode->i_sb, err);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_write_inode()
|
|
*
|
|
* We are called from a few places:
|
|
*
|
|
* - Within generic_file_write() for O_SYNC files.
|
|
* Here, there will be no transaction running. We wait for any running
|
|
* transaction to commit.
|
|
*
|
|
* - Within sys_sync(), kupdate and such.
|
|
* We wait on commit, if tol to.
|
|
*
|
|
* - Within prune_icache() (PF_MEMALLOC == true)
|
|
* Here we simply return. We can't afford to block kswapd on the
|
|
* journal commit.
|
|
*
|
|
* In all cases it is actually safe for us to return without doing anything,
|
|
* because the inode has been copied into a raw inode buffer in
|
|
* ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
|
|
* knfsd.
|
|
*
|
|
* Note that we are absolutely dependent upon all inode dirtiers doing the
|
|
* right thing: they *must* call mark_inode_dirty() after dirtying info in
|
|
* which we are interested.
|
|
*
|
|
* It would be a bug for them to not do this. The code:
|
|
*
|
|
* mark_inode_dirty(inode)
|
|
* stuff();
|
|
* inode->i_size = expr;
|
|
*
|
|
* is in error because a kswapd-driven write_inode() could occur while
|
|
* `stuff()' is running, and the new i_size will be lost. Plus the inode
|
|
* will no longer be on the superblock's dirty inode list.
|
|
*/
|
|
int ext4_write_inode(struct inode *inode, struct writeback_control *wbc)
|
|
{
|
|
int err;
|
|
|
|
if (current->flags & PF_MEMALLOC)
|
|
return 0;
|
|
|
|
if (EXT4_SB(inode->i_sb)->s_journal) {
|
|
if (ext4_journal_current_handle()) {
|
|
jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
|
|
dump_stack();
|
|
return -EIO;
|
|
}
|
|
|
|
if (wbc->sync_mode != WB_SYNC_ALL)
|
|
return 0;
|
|
|
|
err = ext4_force_commit(inode->i_sb);
|
|
} else {
|
|
struct ext4_iloc iloc;
|
|
|
|
err = __ext4_get_inode_loc(inode, &iloc, 0);
|
|
if (err)
|
|
return err;
|
|
if (wbc->sync_mode == WB_SYNC_ALL)
|
|
sync_dirty_buffer(iloc.bh);
|
|
if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) {
|
|
EXT4_ERROR_INODE_BLOCK(inode, iloc.bh->b_blocknr,
|
|
"IO error syncing inode");
|
|
err = -EIO;
|
|
}
|
|
brelse(iloc.bh);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
|
|
* buffers that are attached to a page stradding i_size and are undergoing
|
|
* commit. In that case we have to wait for commit to finish and try again.
|
|
*/
|
|
static void ext4_wait_for_tail_page_commit(struct inode *inode)
|
|
{
|
|
struct page *page;
|
|
unsigned offset;
|
|
journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
|
|
tid_t commit_tid = 0;
|
|
int ret;
|
|
|
|
offset = inode->i_size & (PAGE_CACHE_SIZE - 1);
|
|
/*
|
|
* All buffers in the last page remain valid? Then there's nothing to
|
|
* do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
|
|
* blocksize case
|
|
*/
|
|
if (offset > PAGE_CACHE_SIZE - (1 << inode->i_blkbits))
|
|
return;
|
|
while (1) {
|
|
page = find_lock_page(inode->i_mapping,
|
|
inode->i_size >> PAGE_CACHE_SHIFT);
|
|
if (!page)
|
|
return;
|
|
ret = __ext4_journalled_invalidatepage(page, offset);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
if (ret != -EBUSY)
|
|
return;
|
|
commit_tid = 0;
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_committing_transaction)
|
|
commit_tid = journal->j_committing_transaction->t_tid;
|
|
read_unlock(&journal->j_state_lock);
|
|
if (commit_tid)
|
|
jbd2_log_wait_commit(journal, commit_tid);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ext4_setattr()
|
|
*
|
|
* Called from notify_change.
|
|
*
|
|
* We want to trap VFS attempts to truncate the file as soon as
|
|
* possible. In particular, we want to make sure that when the VFS
|
|
* shrinks i_size, we put the inode on the orphan list and modify
|
|
* i_disksize immediately, so that during the subsequent flushing of
|
|
* dirty pages and freeing of disk blocks, we can guarantee that any
|
|
* commit will leave the blocks being flushed in an unused state on
|
|
* disk. (On recovery, the inode will get truncated and the blocks will
|
|
* be freed, so we have a strong guarantee that no future commit will
|
|
* leave these blocks visible to the user.)
|
|
*
|
|
* Another thing we have to assure is that if we are in ordered mode
|
|
* and inode is still attached to the committing transaction, we must
|
|
* we start writeout of all the dirty pages which are being truncated.
|
|
* This way we are sure that all the data written in the previous
|
|
* transaction are already on disk (truncate waits for pages under
|
|
* writeback).
|
|
*
|
|
* Called with inode->i_mutex down.
|
|
*/
|
|
int ext4_setattr(struct dentry *dentry, struct iattr *attr)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
int error, rc = 0;
|
|
int orphan = 0;
|
|
const unsigned int ia_valid = attr->ia_valid;
|
|
|
|
error = inode_change_ok(inode, attr);
|
|
if (error)
|
|
return error;
|
|
|
|
if (is_quota_modification(inode, attr))
|
|
dquot_initialize(inode);
|
|
if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)) ||
|
|
(ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid))) {
|
|
handle_t *handle;
|
|
|
|
/* (user+group)*(old+new) structure, inode write (sb,
|
|
* inode block, ? - but truncate inode update has it) */
|
|
handle = ext4_journal_start(inode, (EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+
|
|
EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb))+3);
|
|
if (IS_ERR(handle)) {
|
|
error = PTR_ERR(handle);
|
|
goto err_out;
|
|
}
|
|
error = dquot_transfer(inode, attr);
|
|
if (error) {
|
|
ext4_journal_stop(handle);
|
|
return error;
|
|
}
|
|
/* Update corresponding info in inode so that everything is in
|
|
* one transaction */
|
|
if (attr->ia_valid & ATTR_UID)
|
|
inode->i_uid = attr->ia_uid;
|
|
if (attr->ia_valid & ATTR_GID)
|
|
inode->i_gid = attr->ia_gid;
|
|
error = ext4_mark_inode_dirty(handle, inode);
|
|
ext4_journal_stop(handle);
|
|
}
|
|
|
|
if (attr->ia_valid & ATTR_SIZE) {
|
|
|
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
|
|
if (attr->ia_size > sbi->s_bitmap_maxbytes)
|
|
return -EFBIG;
|
|
}
|
|
}
|
|
|
|
if (S_ISREG(inode->i_mode) &&
|
|
attr->ia_valid & ATTR_SIZE &&
|
|
(attr->ia_size < inode->i_size)) {
|
|
handle_t *handle;
|
|
|
|
handle = ext4_journal_start(inode, 3);
|
|
if (IS_ERR(handle)) {
|
|
error = PTR_ERR(handle);
|
|
goto err_out;
|
|
}
|
|
if (ext4_handle_valid(handle)) {
|
|
error = ext4_orphan_add(handle, inode);
|
|
orphan = 1;
|
|
}
|
|
EXT4_I(inode)->i_disksize = attr->ia_size;
|
|
rc = ext4_mark_inode_dirty(handle, inode);
|
|
if (!error)
|
|
error = rc;
|
|
ext4_journal_stop(handle);
|
|
|
|
if (ext4_should_order_data(inode)) {
|
|
error = ext4_begin_ordered_truncate(inode,
|
|
attr->ia_size);
|
|
if (error) {
|
|
/* Do as much error cleanup as possible */
|
|
handle = ext4_journal_start(inode, 3);
|
|
if (IS_ERR(handle)) {
|
|
ext4_orphan_del(NULL, inode);
|
|
goto err_out;
|
|
}
|
|
ext4_orphan_del(handle, inode);
|
|
orphan = 0;
|
|
ext4_journal_stop(handle);
|
|
goto err_out;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (attr->ia_valid & ATTR_SIZE) {
|
|
if (attr->ia_size != inode->i_size) {
|
|
loff_t oldsize = inode->i_size;
|
|
|
|
i_size_write(inode, attr->ia_size);
|
|
/*
|
|
* Blocks are going to be removed from the inode. Wait
|
|
* for dio in flight. Temporarily disable
|
|
* dioread_nolock to prevent livelock.
|
|
*/
|
|
if (orphan) {
|
|
if (!ext4_should_journal_data(inode)) {
|
|
ext4_inode_block_unlocked_dio(inode);
|
|
inode_dio_wait(inode);
|
|
ext4_inode_resume_unlocked_dio(inode);
|
|
} else
|
|
ext4_wait_for_tail_page_commit(inode);
|
|
}
|
|
/*
|
|
* Truncate pagecache after we've waited for commit
|
|
* in data=journal mode to make pages freeable.
|
|
*/
|
|
truncate_pagecache(inode, oldsize, inode->i_size);
|
|
}
|
|
ext4_truncate(inode);
|
|
}
|
|
|
|
if (!rc) {
|
|
setattr_copy(inode, attr);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
/*
|
|
* If the call to ext4_truncate failed to get a transaction handle at
|
|
* all, we need to clean up the in-core orphan list manually.
|
|
*/
|
|
if (orphan && inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
|
|
if (!rc && (ia_valid & ATTR_MODE))
|
|
rc = ext4_acl_chmod(inode);
|
|
|
|
err_out:
|
|
ext4_std_error(inode->i_sb, error);
|
|
if (!error)
|
|
error = rc;
|
|
return error;
|
|
}
|
|
|
|
int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
|
|
struct kstat *stat)
|
|
{
|
|
struct inode *inode;
|
|
unsigned long delalloc_blocks;
|
|
|
|
inode = dentry->d_inode;
|
|
generic_fillattr(inode, stat);
|
|
|
|
/*
|
|
* We can't update i_blocks if the block allocation is delayed
|
|
* otherwise in the case of system crash before the real block
|
|
* allocation is done, we will have i_blocks inconsistent with
|
|
* on-disk file blocks.
|
|
* We always keep i_blocks updated together with real
|
|
* allocation. But to not confuse with user, stat
|
|
* will return the blocks that include the delayed allocation
|
|
* blocks for this file.
|
|
*/
|
|
delalloc_blocks = EXT4_C2B(EXT4_SB(inode->i_sb),
|
|
EXT4_I(inode)->i_reserved_data_blocks);
|
|
|
|
stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9;
|
|
return 0;
|
|
}
|
|
|
|
static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
|
|
{
|
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
|
|
return ext4_ind_trans_blocks(inode, nrblocks, chunk);
|
|
return ext4_ext_index_trans_blocks(inode, nrblocks, chunk);
|
|
}
|
|
|
|
/*
|
|
* Account for index blocks, block groups bitmaps and block group
|
|
* descriptor blocks if modify datablocks and index blocks
|
|
* worse case, the indexs blocks spread over different block groups
|
|
*
|
|
* If datablocks are discontiguous, they are possible to spread over
|
|
* different block groups too. If they are contiguous, with flexbg,
|
|
* they could still across block group boundary.
|
|
*
|
|
* Also account for superblock, inode, quota and xattr blocks
|
|
*/
|
|
static int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk)
|
|
{
|
|
ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb);
|
|
int gdpblocks;
|
|
int idxblocks;
|
|
int ret = 0;
|
|
|
|
/*
|
|
* How many index blocks need to touch to modify nrblocks?
|
|
* The "Chunk" flag indicating whether the nrblocks is
|
|
* physically contiguous on disk
|
|
*
|
|
* For Direct IO and fallocate, they calls get_block to allocate
|
|
* one single extent at a time, so they could set the "Chunk" flag
|
|
*/
|
|
idxblocks = ext4_index_trans_blocks(inode, nrblocks, chunk);
|
|
|
|
ret = idxblocks;
|
|
|
|
/*
|
|
* Now let's see how many group bitmaps and group descriptors need
|
|
* to account
|
|
*/
|
|
groups = idxblocks;
|
|
if (chunk)
|
|
groups += 1;
|
|
else
|
|
groups += nrblocks;
|
|
|
|
gdpblocks = groups;
|
|
if (groups > ngroups)
|
|
groups = ngroups;
|
|
if (groups > EXT4_SB(inode->i_sb)->s_gdb_count)
|
|
gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count;
|
|
|
|
/* bitmaps and block group descriptor blocks */
|
|
ret += groups + gdpblocks;
|
|
|
|
/* Blocks for super block, inode, quota and xattr blocks */
|
|
ret += EXT4_META_TRANS_BLOCKS(inode->i_sb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Calculate the total number of credits to reserve to fit
|
|
* the modification of a single pages into a single transaction,
|
|
* which may include multiple chunks of block allocations.
|
|
*
|
|
* This could be called via ext4_write_begin()
|
|
*
|
|
* We need to consider the worse case, when
|
|
* one new block per extent.
|
|
*/
|
|
int ext4_writepage_trans_blocks(struct inode *inode)
|
|
{
|
|
int bpp = ext4_journal_blocks_per_page(inode);
|
|
int ret;
|
|
|
|
ret = ext4_meta_trans_blocks(inode, bpp, 0);
|
|
|
|
/* Account for data blocks for journalled mode */
|
|
if (ext4_should_journal_data(inode))
|
|
ret += bpp;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Calculate the journal credits for a chunk of data modification.
|
|
*
|
|
* This is called from DIO, fallocate or whoever calling
|
|
* ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
|
|
*
|
|
* journal buffers for data blocks are not included here, as DIO
|
|
* and fallocate do no need to journal data buffers.
|
|
*/
|
|
int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks)
|
|
{
|
|
return ext4_meta_trans_blocks(inode, nrblocks, 1);
|
|
}
|
|
|
|
/*
|
|
* The caller must have previously called ext4_reserve_inode_write().
|
|
* Give this, we know that the caller already has write access to iloc->bh.
|
|
*/
|
|
int ext4_mark_iloc_dirty(handle_t *handle,
|
|
struct inode *inode, struct ext4_iloc *iloc)
|
|
{
|
|
int err = 0;
|
|
|
|
if (IS_I_VERSION(inode))
|
|
inode_inc_iversion(inode);
|
|
|
|
/* the do_update_inode consumes one bh->b_count */
|
|
get_bh(iloc->bh);
|
|
|
|
/* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
|
|
err = ext4_do_update_inode(handle, inode, iloc);
|
|
put_bh(iloc->bh);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* On success, We end up with an outstanding reference count against
|
|
* iloc->bh. This _must_ be cleaned up later.
|
|
*/
|
|
|
|
int
|
|
ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
|
|
struct ext4_iloc *iloc)
|
|
{
|
|
int err;
|
|
|
|
err = ext4_get_inode_loc(inode, iloc);
|
|
if (!err) {
|
|
BUFFER_TRACE(iloc->bh, "get_write_access");
|
|
err = ext4_journal_get_write_access(handle, iloc->bh);
|
|
if (err) {
|
|
brelse(iloc->bh);
|
|
iloc->bh = NULL;
|
|
}
|
|
}
|
|
ext4_std_error(inode->i_sb, err);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Expand an inode by new_extra_isize bytes.
|
|
* Returns 0 on success or negative error number on failure.
|
|
*/
|
|
static int ext4_expand_extra_isize(struct inode *inode,
|
|
unsigned int new_extra_isize,
|
|
struct ext4_iloc iloc,
|
|
handle_t *handle)
|
|
{
|
|
struct ext4_inode *raw_inode;
|
|
struct ext4_xattr_ibody_header *header;
|
|
|
|
if (EXT4_I(inode)->i_extra_isize >= new_extra_isize)
|
|
return 0;
|
|
|
|
raw_inode = ext4_raw_inode(&iloc);
|
|
|
|
header = IHDR(inode, raw_inode);
|
|
|
|
/* No extended attributes present */
|
|
if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR) ||
|
|
header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) {
|
|
memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0,
|
|
new_extra_isize);
|
|
EXT4_I(inode)->i_extra_isize = new_extra_isize;
|
|
return 0;
|
|
}
|
|
|
|
/* try to expand with EAs present */
|
|
return ext4_expand_extra_isize_ea(inode, new_extra_isize,
|
|
raw_inode, handle);
|
|
}
|
|
|
|
/*
|
|
* What we do here is to mark the in-core inode as clean with respect to inode
|
|
* dirtiness (it may still be data-dirty).
|
|
* This means that the in-core inode may be reaped by prune_icache
|
|
* without having to perform any I/O. This is a very good thing,
|
|
* because *any* task may call prune_icache - even ones which
|
|
* have a transaction open against a different journal.
|
|
*
|
|
* Is this cheating? Not really. Sure, we haven't written the
|
|
* inode out, but prune_icache isn't a user-visible syncing function.
|
|
* Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
|
|
* we start and wait on commits.
|
|
*/
|
|
int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
|
|
{
|
|
struct ext4_iloc iloc;
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
static unsigned int mnt_count;
|
|
int err, ret;
|
|
|
|
might_sleep();
|
|
trace_ext4_mark_inode_dirty(inode, _RET_IP_);
|
|
err = ext4_reserve_inode_write(handle, inode, &iloc);
|
|
if (ext4_handle_valid(handle) &&
|
|
EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize &&
|
|
!ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) {
|
|
/*
|
|
* We need extra buffer credits since we may write into EA block
|
|
* with this same handle. If journal_extend fails, then it will
|
|
* only result in a minor loss of functionality for that inode.
|
|
* If this is felt to be critical, then e2fsck should be run to
|
|
* force a large enough s_min_extra_isize.
|
|
*/
|
|
if ((jbd2_journal_extend(handle,
|
|
EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) {
|
|
ret = ext4_expand_extra_isize(inode,
|
|
sbi->s_want_extra_isize,
|
|
iloc, handle);
|
|
if (ret) {
|
|
ext4_set_inode_state(inode,
|
|
EXT4_STATE_NO_EXPAND);
|
|
if (mnt_count !=
|
|
le16_to_cpu(sbi->s_es->s_mnt_count)) {
|
|
ext4_warning(inode->i_sb,
|
|
"Unable to expand inode %lu. Delete"
|
|
" some EAs or run e2fsck.",
|
|
inode->i_ino);
|
|
mnt_count =
|
|
le16_to_cpu(sbi->s_es->s_mnt_count);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (!err)
|
|
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_dirty_inode() is called from __mark_inode_dirty()
|
|
*
|
|
* We're really interested in the case where a file is being extended.
|
|
* i_size has been changed by generic_commit_write() and we thus need
|
|
* to include the updated inode in the current transaction.
|
|
*
|
|
* Also, dquot_alloc_block() will always dirty the inode when blocks
|
|
* are allocated to the file.
|
|
*
|
|
* If the inode is marked synchronous, we don't honour that here - doing
|
|
* so would cause a commit on atime updates, which we don't bother doing.
|
|
* We handle synchronous inodes at the highest possible level.
|
|
*/
|
|
void ext4_dirty_inode(struct inode *inode, int flags)
|
|
{
|
|
handle_t *handle;
|
|
|
|
handle = ext4_journal_start(inode, 2);
|
|
if (IS_ERR(handle))
|
|
goto out;
|
|
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
|
|
ext4_journal_stop(handle);
|
|
out:
|
|
return;
|
|
}
|
|
|
|
#if 0
|
|
/*
|
|
* Bind an inode's backing buffer_head into this transaction, to prevent
|
|
* it from being flushed to disk early. Unlike
|
|
* ext4_reserve_inode_write, this leaves behind no bh reference and
|
|
* returns no iloc structure, so the caller needs to repeat the iloc
|
|
* lookup to mark the inode dirty later.
|
|
*/
|
|
static int ext4_pin_inode(handle_t *handle, struct inode *inode)
|
|
{
|
|
struct ext4_iloc iloc;
|
|
|
|
int err = 0;
|
|
if (handle) {
|
|
err = ext4_get_inode_loc(inode, &iloc);
|
|
if (!err) {
|
|
BUFFER_TRACE(iloc.bh, "get_write_access");
|
|
err = jbd2_journal_get_write_access(handle, iloc.bh);
|
|
if (!err)
|
|
err = ext4_handle_dirty_metadata(handle,
|
|
NULL,
|
|
iloc.bh);
|
|
brelse(iloc.bh);
|
|
}
|
|
}
|
|
ext4_std_error(inode->i_sb, err);
|
|
return err;
|
|
}
|
|
#endif
|
|
|
|
int ext4_change_inode_journal_flag(struct inode *inode, int val)
|
|
{
|
|
journal_t *journal;
|
|
handle_t *handle;
|
|
int err;
|
|
|
|
/*
|
|
* We have to be very careful here: changing a data block's
|
|
* journaling status dynamically is dangerous. If we write a
|
|
* data block to the journal, change the status and then delete
|
|
* that block, we risk forgetting to revoke the old log record
|
|
* from the journal and so a subsequent replay can corrupt data.
|
|
* So, first we make sure that the journal is empty and that
|
|
* nobody is changing anything.
|
|
*/
|
|
|
|
journal = EXT4_JOURNAL(inode);
|
|
if (!journal)
|
|
return 0;
|
|
if (is_journal_aborted(journal))
|
|
return -EROFS;
|
|
/* We have to allocate physical blocks for delalloc blocks
|
|
* before flushing journal. otherwise delalloc blocks can not
|
|
* be allocated any more. even more truncate on delalloc blocks
|
|
* could trigger BUG by flushing delalloc blocks in journal.
|
|
* There is no delalloc block in non-journal data mode.
|
|
*/
|
|
if (val && test_opt(inode->i_sb, DELALLOC)) {
|
|
err = ext4_alloc_da_blocks(inode);
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
|
|
/* Wait for all existing dio workers */
|
|
ext4_inode_block_unlocked_dio(inode);
|
|
inode_dio_wait(inode);
|
|
|
|
jbd2_journal_lock_updates(journal);
|
|
|
|
/*
|
|
* OK, there are no updates running now, and all cached data is
|
|
* synced to disk. We are now in a completely consistent state
|
|
* which doesn't have anything in the journal, and we know that
|
|
* no filesystem updates are running, so it is safe to modify
|
|
* the inode's in-core data-journaling state flag now.
|
|
*/
|
|
|
|
if (val)
|
|
ext4_set_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
|
|
else {
|
|
jbd2_journal_flush(journal);
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
|
|
}
|
|
ext4_set_aops(inode);
|
|
|
|
jbd2_journal_unlock_updates(journal);
|
|
ext4_inode_resume_unlocked_dio(inode);
|
|
|
|
/* Finally we can mark the inode as dirty. */
|
|
|
|
handle = ext4_journal_start(inode, 1);
|
|
if (IS_ERR(handle))
|
|
return PTR_ERR(handle);
|
|
|
|
err = ext4_mark_inode_dirty(handle, inode);
|
|
ext4_handle_sync(handle);
|
|
ext4_journal_stop(handle);
|
|
ext4_std_error(inode->i_sb, err);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
return !buffer_mapped(bh);
|
|
}
|
|
|
|
int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
|
|
{
|
|
struct page *page = vmf->page;
|
|
loff_t size;
|
|
unsigned long len;
|
|
int ret;
|
|
struct file *file = vma->vm_file;
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
handle_t *handle;
|
|
get_block_t *get_block;
|
|
int retries = 0;
|
|
|
|
sb_start_pagefault(inode->i_sb);
|
|
file_update_time(vma->vm_file);
|
|
/* Delalloc case is easy... */
|
|
if (test_opt(inode->i_sb, DELALLOC) &&
|
|
!ext4_should_journal_data(inode) &&
|
|
!ext4_nonda_switch(inode->i_sb)) {
|
|
do {
|
|
ret = __block_page_mkwrite(vma, vmf,
|
|
ext4_da_get_block_prep);
|
|
} while (ret == -ENOSPC &&
|
|
ext4_should_retry_alloc(inode->i_sb, &retries));
|
|
goto out_ret;
|
|
}
|
|
|
|
lock_page(page);
|
|
size = i_size_read(inode);
|
|
/* Page got truncated from under us? */
|
|
if (page->mapping != mapping || page_offset(page) > size) {
|
|
unlock_page(page);
|
|
ret = VM_FAULT_NOPAGE;
|
|
goto out;
|
|
}
|
|
|
|
if (page->index == size >> PAGE_CACHE_SHIFT)
|
|
len = size & ~PAGE_CACHE_MASK;
|
|
else
|
|
len = PAGE_CACHE_SIZE;
|
|
/*
|
|
* Return if we have all the buffers mapped. This avoids the need to do
|
|
* journal_start/journal_stop which can block and take a long time
|
|
*/
|
|
if (page_has_buffers(page)) {
|
|
if (!ext4_walk_page_buffers(NULL, page_buffers(page),
|
|
0, len, NULL,
|
|
ext4_bh_unmapped)) {
|
|
/* Wait so that we don't change page under IO */
|
|
wait_on_page_writeback(page);
|
|
ret = VM_FAULT_LOCKED;
|
|
goto out;
|
|
}
|
|
}
|
|
unlock_page(page);
|
|
/* OK, we need to fill the hole... */
|
|
if (ext4_should_dioread_nolock(inode))
|
|
get_block = ext4_get_block_write;
|
|
else
|
|
get_block = ext4_get_block;
|
|
retry_alloc:
|
|
handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
|
|
if (IS_ERR(handle)) {
|
|
ret = VM_FAULT_SIGBUS;
|
|
goto out;
|
|
}
|
|
ret = __block_page_mkwrite(vma, vmf, get_block);
|
|
if (!ret && ext4_should_journal_data(inode)) {
|
|
if (ext4_walk_page_buffers(handle, page_buffers(page), 0,
|
|
PAGE_CACHE_SIZE, NULL, do_journal_get_write_access)) {
|
|
unlock_page(page);
|
|
ret = VM_FAULT_SIGBUS;
|
|
ext4_journal_stop(handle);
|
|
goto out;
|
|
}
|
|
ext4_set_inode_state(inode, EXT4_STATE_JDATA);
|
|
}
|
|
ext4_journal_stop(handle);
|
|
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
|
|
goto retry_alloc;
|
|
out_ret:
|
|
ret = block_page_mkwrite_return(ret);
|
|
out:
|
|
sb_end_pagefault(inode->i_sb);
|
|
return ret;
|
|
}
|