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https://github.com/edk2-porting/linux-next.git
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46d0733801
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
802 lines
20 KiB
C
802 lines
20 KiB
C
/*
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* fs/logfs/dir.c - directory-related code
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*
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* As should be obvious for Linux kernel code, license is GPLv2
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*
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* Copyright (c) 2005-2008 Joern Engel <joern@logfs.org>
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*/
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#include "logfs.h"
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#include <linux/slab.h>
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/*
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* Atomic dir operations
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*
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* Directory operations are by default not atomic. Dentries and Inodes are
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* created/removed/altered in separate operations. Therefore we need to do
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* a small amount of journaling.
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*
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* Create, link, mkdir, mknod and symlink all share the same function to do
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* the work: __logfs_create. This function works in two atomic steps:
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* 1. allocate inode (remember in journal)
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* 2. allocate dentry (clear journal)
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*
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* As we can only get interrupted between the two, when the inode we just
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* created is simply stored in the anchor. On next mount, if we were
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* interrupted, we delete the inode. From a users point of view the
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* operation never happened.
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*
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* Unlink and rmdir also share the same function: unlink. Again, this
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* function works in two atomic steps
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* 1. remove dentry (remember inode in journal)
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* 2. unlink inode (clear journal)
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*
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* And again, on the next mount, if we were interrupted, we delete the inode.
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* From a users point of view the operation succeeded.
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*
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* Rename is the real pain to deal with, harder than all the other methods
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* combined. Depending on the circumstances we can run into three cases.
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* A "target rename" where the target dentry already existed, a "local
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* rename" where both parent directories are identical or a "cross-directory
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* rename" in the remaining case.
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*
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* Local rename is atomic, as the old dentry is simply rewritten with a new
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* name.
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*
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* Cross-directory rename works in two steps, similar to __logfs_create and
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* logfs_unlink:
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* 1. Write new dentry (remember old dentry in journal)
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* 2. Remove old dentry (clear journal)
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*
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* Here we remember a dentry instead of an inode. On next mount, if we were
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* interrupted, we delete the dentry. From a users point of view, the
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* operation succeeded.
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*
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* Target rename works in three atomic steps:
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* 1. Attach old inode to new dentry (remember old dentry and new inode)
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* 2. Remove old dentry (still remember the new inode)
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* 3. Remove victim inode
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*
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* Here we remember both an inode an a dentry. If we get interrupted
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* between steps 1 and 2, we delete both the dentry and the inode. If
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* we get interrupted between steps 2 and 3, we delete just the inode.
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* In either case, the remaining objects are deleted on next mount. From
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* a users point of view, the operation succeeded.
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*/
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static int write_dir(struct inode *dir, struct logfs_disk_dentry *dd,
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loff_t pos)
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{
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return logfs_inode_write(dir, dd, sizeof(*dd), pos, WF_LOCK, NULL);
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}
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static int write_inode(struct inode *inode)
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{
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return __logfs_write_inode(inode, NULL, WF_LOCK);
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}
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static s64 dir_seek_data(struct inode *inode, s64 pos)
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{
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s64 new_pos = logfs_seek_data(inode, pos);
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return max(pos, new_pos - 1);
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}
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static int beyond_eof(struct inode *inode, loff_t bix)
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{
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loff_t pos = bix << inode->i_sb->s_blocksize_bits;
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return pos >= i_size_read(inode);
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}
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/*
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* Prime value was chosen to be roughly 256 + 26. r5 hash uses 11,
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* so short names (len <= 9) don't even occupy the complete 32bit name
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* space. A prime >256 ensures short names quickly spread the 32bit
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* name space. Add about 26 for the estimated amount of information
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* of each character and pick a prime nearby, preferably a bit-sparse
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* one.
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*/
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static u32 hash_32(const char *s, int len, u32 seed)
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{
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u32 hash = seed;
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int i;
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for (i = 0; i < len; i++)
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hash = hash * 293 + s[i];
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return hash;
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}
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/*
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* We have to satisfy several conflicting requirements here. Small
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* directories should stay fairly compact and not require too many
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* indirect blocks. The number of possible locations for a given hash
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* should be small to make lookup() fast. And we should try hard not
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* to overflow the 32bit name space or nfs and 32bit host systems will
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* be unhappy.
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*
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* So we use the following scheme. First we reduce the hash to 0..15
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* and try a direct block. If that is occupied we reduce the hash to
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* 16..255 and try an indirect block. Same for 2x and 3x indirect
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* blocks. Lastly we reduce the hash to 0x800_0000 .. 0xffff_ffff,
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* but use buckets containing eight entries instead of a single one.
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*
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* Using 16 entries should allow for a reasonable amount of hash
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* collisions, so the 32bit name space can be packed fairly tight
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* before overflowing. Oh and currently we don't overflow but return
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* and error.
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*
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* How likely are collisions? Doing the appropriate math is beyond me
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* and the Bronstein textbook. But running a test program to brute
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* force collisions for a couple of days showed that on average the
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* first collision occurs after 598M entries, with 290M being the
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* smallest result. Obviously 21 entries could already cause a
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* collision if all entries are carefully chosen.
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*/
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static pgoff_t hash_index(u32 hash, int round)
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{
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u32 i0_blocks = I0_BLOCKS;
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u32 i1_blocks = I1_BLOCKS;
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u32 i2_blocks = I2_BLOCKS;
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u32 i3_blocks = I3_BLOCKS;
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switch (round) {
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case 0:
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return hash % i0_blocks;
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case 1:
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return i0_blocks + hash % (i1_blocks - i0_blocks);
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case 2:
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return i1_blocks + hash % (i2_blocks - i1_blocks);
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case 3:
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return i2_blocks + hash % (i3_blocks - i2_blocks);
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case 4 ... 19:
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return i3_blocks + 16 * (hash % (((1<<31) - i3_blocks) / 16))
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+ round - 4;
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}
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BUG();
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}
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static struct page *logfs_get_dd_page(struct inode *dir, struct dentry *dentry)
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{
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struct qstr *name = &dentry->d_name;
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struct page *page;
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struct logfs_disk_dentry *dd;
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u32 hash = hash_32(name->name, name->len, 0);
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pgoff_t index;
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int round;
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if (name->len > LOGFS_MAX_NAMELEN)
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return ERR_PTR(-ENAMETOOLONG);
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for (round = 0; round < 20; round++) {
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index = hash_index(hash, round);
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if (beyond_eof(dir, index))
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return NULL;
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if (!logfs_exist_block(dir, index))
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continue;
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page = read_cache_page(dir->i_mapping, index,
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(filler_t *)logfs_readpage, NULL);
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if (IS_ERR(page))
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return page;
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dd = kmap_atomic(page);
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BUG_ON(dd->namelen == 0);
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if (name->len != be16_to_cpu(dd->namelen) ||
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memcmp(name->name, dd->name, name->len)) {
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kunmap_atomic(dd);
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page_cache_release(page);
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continue;
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}
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kunmap_atomic(dd);
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return page;
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}
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return NULL;
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}
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static int logfs_remove_inode(struct inode *inode)
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{
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int ret;
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drop_nlink(inode);
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ret = write_inode(inode);
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LOGFS_BUG_ON(ret, inode->i_sb);
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return ret;
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}
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static void abort_transaction(struct inode *inode, struct logfs_transaction *ta)
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{
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if (logfs_inode(inode)->li_block)
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logfs_inode(inode)->li_block->ta = NULL;
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kfree(ta);
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}
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static int logfs_unlink(struct inode *dir, struct dentry *dentry)
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{
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struct logfs_super *super = logfs_super(dir->i_sb);
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struct inode *inode = dentry->d_inode;
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struct logfs_transaction *ta;
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struct page *page;
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pgoff_t index;
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int ret;
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ta = kzalloc(sizeof(*ta), GFP_KERNEL);
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if (!ta)
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return -ENOMEM;
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ta->state = UNLINK_1;
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ta->ino = inode->i_ino;
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inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
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page = logfs_get_dd_page(dir, dentry);
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if (!page) {
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kfree(ta);
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return -ENOENT;
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}
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if (IS_ERR(page)) {
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kfree(ta);
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return PTR_ERR(page);
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}
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index = page->index;
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page_cache_release(page);
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mutex_lock(&super->s_dirop_mutex);
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logfs_add_transaction(dir, ta);
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ret = logfs_delete(dir, index, NULL);
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if (!ret)
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ret = write_inode(dir);
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if (ret) {
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abort_transaction(dir, ta);
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printk(KERN_ERR"LOGFS: unable to delete inode\n");
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goto out;
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}
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ta->state = UNLINK_2;
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logfs_add_transaction(inode, ta);
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ret = logfs_remove_inode(inode);
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out:
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mutex_unlock(&super->s_dirop_mutex);
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return ret;
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}
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static inline int logfs_empty_dir(struct inode *dir)
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{
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u64 data;
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data = logfs_seek_data(dir, 0) << dir->i_sb->s_blocksize_bits;
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return data >= i_size_read(dir);
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}
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static int logfs_rmdir(struct inode *dir, struct dentry *dentry)
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{
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struct inode *inode = dentry->d_inode;
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if (!logfs_empty_dir(inode))
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return -ENOTEMPTY;
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return logfs_unlink(dir, dentry);
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}
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/* FIXME: readdir currently has it's own dir_walk code. I don't see a good
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* way to combine the two copies */
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static int logfs_readdir(struct file *file, struct dir_context *ctx)
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{
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struct inode *dir = file_inode(file);
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loff_t pos;
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struct page *page;
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struct logfs_disk_dentry *dd;
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if (ctx->pos < 0)
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return -EINVAL;
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if (!dir_emit_dots(file, ctx))
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return 0;
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pos = ctx->pos - 2;
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BUG_ON(pos < 0);
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for (;; pos++, ctx->pos++) {
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bool full;
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if (beyond_eof(dir, pos))
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break;
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if (!logfs_exist_block(dir, pos)) {
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/* deleted dentry */
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pos = dir_seek_data(dir, pos);
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continue;
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}
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page = read_cache_page(dir->i_mapping, pos,
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(filler_t *)logfs_readpage, NULL);
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if (IS_ERR(page))
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return PTR_ERR(page);
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dd = kmap(page);
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BUG_ON(dd->namelen == 0);
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full = !dir_emit(ctx, (char *)dd->name,
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be16_to_cpu(dd->namelen),
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be64_to_cpu(dd->ino), dd->type);
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kunmap(page);
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page_cache_release(page);
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if (full)
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break;
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}
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return 0;
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}
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static void logfs_set_name(struct logfs_disk_dentry *dd, struct qstr *name)
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{
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dd->namelen = cpu_to_be16(name->len);
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memcpy(dd->name, name->name, name->len);
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}
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static struct dentry *logfs_lookup(struct inode *dir, struct dentry *dentry,
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unsigned int flags)
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{
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struct page *page;
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struct logfs_disk_dentry *dd;
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pgoff_t index;
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u64 ino = 0;
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struct inode *inode;
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page = logfs_get_dd_page(dir, dentry);
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if (IS_ERR(page))
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return ERR_CAST(page);
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if (!page) {
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d_add(dentry, NULL);
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return NULL;
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}
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index = page->index;
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dd = kmap_atomic(page);
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ino = be64_to_cpu(dd->ino);
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kunmap_atomic(dd);
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page_cache_release(page);
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inode = logfs_iget(dir->i_sb, ino);
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if (IS_ERR(inode))
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printk(KERN_ERR"LogFS: Cannot read inode #%llx for dentry (%lx, %lx)n",
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ino, dir->i_ino, index);
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return d_splice_alias(inode, dentry);
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}
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static void grow_dir(struct inode *dir, loff_t index)
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{
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index = (index + 1) << dir->i_sb->s_blocksize_bits;
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if (i_size_read(dir) < index)
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i_size_write(dir, index);
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}
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static int logfs_write_dir(struct inode *dir, struct dentry *dentry,
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struct inode *inode)
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{
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struct page *page;
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struct logfs_disk_dentry *dd;
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u32 hash = hash_32(dentry->d_name.name, dentry->d_name.len, 0);
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pgoff_t index;
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int round, err;
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for (round = 0; round < 20; round++) {
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index = hash_index(hash, round);
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if (logfs_exist_block(dir, index))
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continue;
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page = find_or_create_page(dir->i_mapping, index, GFP_KERNEL);
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if (!page)
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return -ENOMEM;
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dd = kmap_atomic(page);
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memset(dd, 0, sizeof(*dd));
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dd->ino = cpu_to_be64(inode->i_ino);
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dd->type = logfs_type(inode);
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logfs_set_name(dd, &dentry->d_name);
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kunmap_atomic(dd);
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err = logfs_write_buf(dir, page, WF_LOCK);
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unlock_page(page);
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page_cache_release(page);
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if (!err)
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grow_dir(dir, index);
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return err;
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}
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/* FIXME: Is there a better return value? In most cases neither
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* the filesystem nor the directory are full. But we have had
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* too many collisions for this particular hash and no fallback.
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*/
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return -ENOSPC;
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}
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static int __logfs_create(struct inode *dir, struct dentry *dentry,
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struct inode *inode, const char *dest, long destlen)
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{
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struct logfs_super *super = logfs_super(dir->i_sb);
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struct logfs_inode *li = logfs_inode(inode);
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struct logfs_transaction *ta;
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int ret;
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ta = kzalloc(sizeof(*ta), GFP_KERNEL);
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if (!ta) {
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drop_nlink(inode);
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iput(inode);
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return -ENOMEM;
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}
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ta->state = CREATE_1;
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ta->ino = inode->i_ino;
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mutex_lock(&super->s_dirop_mutex);
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logfs_add_transaction(inode, ta);
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if (dest) {
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/* symlink */
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ret = logfs_inode_write(inode, dest, destlen, 0, WF_LOCK, NULL);
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if (!ret)
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ret = write_inode(inode);
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} else {
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/* creat/mkdir/mknod */
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ret = write_inode(inode);
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}
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if (ret) {
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abort_transaction(inode, ta);
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li->li_flags |= LOGFS_IF_STILLBORN;
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/* FIXME: truncate symlink */
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drop_nlink(inode);
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iput(inode);
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goto out;
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}
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ta->state = CREATE_2;
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logfs_add_transaction(dir, ta);
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ret = logfs_write_dir(dir, dentry, inode);
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/* sync directory */
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if (!ret)
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ret = write_inode(dir);
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if (ret) {
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logfs_del_transaction(dir, ta);
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ta->state = CREATE_2;
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logfs_add_transaction(inode, ta);
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logfs_remove_inode(inode);
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iput(inode);
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goto out;
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}
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d_instantiate(dentry, inode);
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out:
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mutex_unlock(&super->s_dirop_mutex);
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return ret;
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}
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static int logfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
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{
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struct inode *inode;
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/*
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* FIXME: why do we have to fill in S_IFDIR, while the mode is
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* correct for mknod, creat, etc.? Smells like the vfs *should*
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* do it for us but for some reason fails to do so.
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*/
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inode = logfs_new_inode(dir, S_IFDIR | mode);
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if (IS_ERR(inode))
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return PTR_ERR(inode);
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inode->i_op = &logfs_dir_iops;
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inode->i_fop = &logfs_dir_fops;
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return __logfs_create(dir, dentry, inode, NULL, 0);
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}
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static int logfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
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bool excl)
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{
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struct inode *inode;
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inode = logfs_new_inode(dir, mode);
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if (IS_ERR(inode))
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return PTR_ERR(inode);
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inode->i_op = &logfs_reg_iops;
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inode->i_fop = &logfs_reg_fops;
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inode->i_mapping->a_ops = &logfs_reg_aops;
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return __logfs_create(dir, dentry, inode, NULL, 0);
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}
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static int logfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
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dev_t rdev)
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{
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struct inode *inode;
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if (dentry->d_name.len > LOGFS_MAX_NAMELEN)
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return -ENAMETOOLONG;
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inode = logfs_new_inode(dir, mode);
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if (IS_ERR(inode))
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return PTR_ERR(inode);
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|
init_special_inode(inode, mode, rdev);
|
|
|
|
return __logfs_create(dir, dentry, inode, NULL, 0);
|
|
}
|
|
|
|
static int logfs_symlink(struct inode *dir, struct dentry *dentry,
|
|
const char *target)
|
|
{
|
|
struct inode *inode;
|
|
size_t destlen = strlen(target) + 1;
|
|
|
|
if (destlen > dir->i_sb->s_blocksize)
|
|
return -ENAMETOOLONG;
|
|
|
|
inode = logfs_new_inode(dir, S_IFLNK | 0777);
|
|
if (IS_ERR(inode))
|
|
return PTR_ERR(inode);
|
|
|
|
inode->i_op = &logfs_symlink_iops;
|
|
inode->i_mapping->a_ops = &logfs_reg_aops;
|
|
|
|
return __logfs_create(dir, dentry, inode, target, destlen);
|
|
}
|
|
|
|
static int logfs_link(struct dentry *old_dentry, struct inode *dir,
|
|
struct dentry *dentry)
|
|
{
|
|
struct inode *inode = old_dentry->d_inode;
|
|
|
|
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
|
|
ihold(inode);
|
|
inc_nlink(inode);
|
|
mark_inode_dirty_sync(inode);
|
|
|
|
return __logfs_create(dir, dentry, inode, NULL, 0);
|
|
}
|
|
|
|
static int logfs_get_dd(struct inode *dir, struct dentry *dentry,
|
|
struct logfs_disk_dentry *dd, loff_t *pos)
|
|
{
|
|
struct page *page;
|
|
void *map;
|
|
|
|
page = logfs_get_dd_page(dir, dentry);
|
|
if (IS_ERR(page))
|
|
return PTR_ERR(page);
|
|
*pos = page->index;
|
|
map = kmap_atomic(page);
|
|
memcpy(dd, map, sizeof(*dd));
|
|
kunmap_atomic(map);
|
|
page_cache_release(page);
|
|
return 0;
|
|
}
|
|
|
|
static int logfs_delete_dd(struct inode *dir, loff_t pos)
|
|
{
|
|
/*
|
|
* Getting called with pos somewhere beyond eof is either a goofup
|
|
* within this file or means someone maliciously edited the
|
|
* (crc-protected) journal.
|
|
*/
|
|
BUG_ON(beyond_eof(dir, pos));
|
|
dir->i_ctime = dir->i_mtime = CURRENT_TIME;
|
|
log_dir(" Delete dentry (%lx, %llx)\n", dir->i_ino, pos);
|
|
return logfs_delete(dir, pos, NULL);
|
|
}
|
|
|
|
/*
|
|
* Cross-directory rename, target does not exist. Just a little nasty.
|
|
* Create a new dentry in the target dir, then remove the old dentry,
|
|
* all the while taking care to remember our operation in the journal.
|
|
*/
|
|
static int logfs_rename_cross(struct inode *old_dir, struct dentry *old_dentry,
|
|
struct inode *new_dir, struct dentry *new_dentry)
|
|
{
|
|
struct logfs_super *super = logfs_super(old_dir->i_sb);
|
|
struct logfs_disk_dentry dd;
|
|
struct logfs_transaction *ta;
|
|
loff_t pos;
|
|
int err;
|
|
|
|
/* 1. locate source dd */
|
|
err = logfs_get_dd(old_dir, old_dentry, &dd, &pos);
|
|
if (err)
|
|
return err;
|
|
|
|
ta = kzalloc(sizeof(*ta), GFP_KERNEL);
|
|
if (!ta)
|
|
return -ENOMEM;
|
|
|
|
ta->state = CROSS_RENAME_1;
|
|
ta->dir = old_dir->i_ino;
|
|
ta->pos = pos;
|
|
|
|
/* 2. write target dd */
|
|
mutex_lock(&super->s_dirop_mutex);
|
|
logfs_add_transaction(new_dir, ta);
|
|
err = logfs_write_dir(new_dir, new_dentry, old_dentry->d_inode);
|
|
if (!err)
|
|
err = write_inode(new_dir);
|
|
|
|
if (err) {
|
|
super->s_rename_dir = 0;
|
|
super->s_rename_pos = 0;
|
|
abort_transaction(new_dir, ta);
|
|
goto out;
|
|
}
|
|
|
|
/* 3. remove source dd */
|
|
ta->state = CROSS_RENAME_2;
|
|
logfs_add_transaction(old_dir, ta);
|
|
err = logfs_delete_dd(old_dir, pos);
|
|
if (!err)
|
|
err = write_inode(old_dir);
|
|
LOGFS_BUG_ON(err, old_dir->i_sb);
|
|
out:
|
|
mutex_unlock(&super->s_dirop_mutex);
|
|
return err;
|
|
}
|
|
|
|
static int logfs_replace_inode(struct inode *dir, struct dentry *dentry,
|
|
struct logfs_disk_dentry *dd, struct inode *inode)
|
|
{
|
|
loff_t pos;
|
|
int err;
|
|
|
|
err = logfs_get_dd(dir, dentry, dd, &pos);
|
|
if (err)
|
|
return err;
|
|
dd->ino = cpu_to_be64(inode->i_ino);
|
|
dd->type = logfs_type(inode);
|
|
|
|
err = write_dir(dir, dd, pos);
|
|
if (err)
|
|
return err;
|
|
log_dir("Replace dentry (%lx, %llx) %s -> %llx\n", dir->i_ino, pos,
|
|
dd->name, be64_to_cpu(dd->ino));
|
|
return write_inode(dir);
|
|
}
|
|
|
|
/* Target dentry exists - the worst case. We need to attach the source
|
|
* inode to the target dentry, then remove the orphaned target inode and
|
|
* source dentry.
|
|
*/
|
|
static int logfs_rename_target(struct inode *old_dir, struct dentry *old_dentry,
|
|
struct inode *new_dir, struct dentry *new_dentry)
|
|
{
|
|
struct logfs_super *super = logfs_super(old_dir->i_sb);
|
|
struct inode *old_inode = old_dentry->d_inode;
|
|
struct inode *new_inode = new_dentry->d_inode;
|
|
int isdir = S_ISDIR(old_inode->i_mode);
|
|
struct logfs_disk_dentry dd;
|
|
struct logfs_transaction *ta;
|
|
loff_t pos;
|
|
int err;
|
|
|
|
BUG_ON(isdir != S_ISDIR(new_inode->i_mode));
|
|
if (isdir) {
|
|
if (!logfs_empty_dir(new_inode))
|
|
return -ENOTEMPTY;
|
|
}
|
|
|
|
/* 1. locate source dd */
|
|
err = logfs_get_dd(old_dir, old_dentry, &dd, &pos);
|
|
if (err)
|
|
return err;
|
|
|
|
ta = kzalloc(sizeof(*ta), GFP_KERNEL);
|
|
if (!ta)
|
|
return -ENOMEM;
|
|
|
|
ta->state = TARGET_RENAME_1;
|
|
ta->dir = old_dir->i_ino;
|
|
ta->pos = pos;
|
|
ta->ino = new_inode->i_ino;
|
|
|
|
/* 2. attach source inode to target dd */
|
|
mutex_lock(&super->s_dirop_mutex);
|
|
logfs_add_transaction(new_dir, ta);
|
|
err = logfs_replace_inode(new_dir, new_dentry, &dd, old_inode);
|
|
if (err) {
|
|
super->s_rename_dir = 0;
|
|
super->s_rename_pos = 0;
|
|
super->s_victim_ino = 0;
|
|
abort_transaction(new_dir, ta);
|
|
goto out;
|
|
}
|
|
|
|
/* 3. remove source dd */
|
|
ta->state = TARGET_RENAME_2;
|
|
logfs_add_transaction(old_dir, ta);
|
|
err = logfs_delete_dd(old_dir, pos);
|
|
if (!err)
|
|
err = write_inode(old_dir);
|
|
LOGFS_BUG_ON(err, old_dir->i_sb);
|
|
|
|
/* 4. remove target inode */
|
|
ta->state = TARGET_RENAME_3;
|
|
logfs_add_transaction(new_inode, ta);
|
|
err = logfs_remove_inode(new_inode);
|
|
|
|
out:
|
|
mutex_unlock(&super->s_dirop_mutex);
|
|
return err;
|
|
}
|
|
|
|
static int logfs_rename(struct inode *old_dir, struct dentry *old_dentry,
|
|
struct inode *new_dir, struct dentry *new_dentry)
|
|
{
|
|
if (new_dentry->d_inode)
|
|
return logfs_rename_target(old_dir, old_dentry,
|
|
new_dir, new_dentry);
|
|
return logfs_rename_cross(old_dir, old_dentry, new_dir, new_dentry);
|
|
}
|
|
|
|
/* No locking done here, as this is called before .get_sb() returns. */
|
|
int logfs_replay_journal(struct super_block *sb)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
struct inode *inode;
|
|
u64 ino, pos;
|
|
int err;
|
|
|
|
if (super->s_victim_ino) {
|
|
/* delete victim inode */
|
|
ino = super->s_victim_ino;
|
|
printk(KERN_INFO"LogFS: delete unmapped inode #%llx\n", ino);
|
|
inode = logfs_iget(sb, ino);
|
|
if (IS_ERR(inode))
|
|
goto fail;
|
|
|
|
LOGFS_BUG_ON(i_size_read(inode) > 0, sb);
|
|
super->s_victim_ino = 0;
|
|
err = logfs_remove_inode(inode);
|
|
iput(inode);
|
|
if (err) {
|
|
super->s_victim_ino = ino;
|
|
goto fail;
|
|
}
|
|
}
|
|
if (super->s_rename_dir) {
|
|
/* delete old dd from rename */
|
|
ino = super->s_rename_dir;
|
|
pos = super->s_rename_pos;
|
|
printk(KERN_INFO"LogFS: delete unbacked dentry (%llx, %llx)\n",
|
|
ino, pos);
|
|
inode = logfs_iget(sb, ino);
|
|
if (IS_ERR(inode))
|
|
goto fail;
|
|
|
|
super->s_rename_dir = 0;
|
|
super->s_rename_pos = 0;
|
|
err = logfs_delete_dd(inode, pos);
|
|
iput(inode);
|
|
if (err) {
|
|
super->s_rename_dir = ino;
|
|
super->s_rename_pos = pos;
|
|
goto fail;
|
|
}
|
|
}
|
|
return 0;
|
|
fail:
|
|
LOGFS_BUG(sb);
|
|
return -EIO;
|
|
}
|
|
|
|
const struct inode_operations logfs_symlink_iops = {
|
|
.readlink = generic_readlink,
|
|
.follow_link = page_follow_link_light,
|
|
};
|
|
|
|
const struct inode_operations logfs_dir_iops = {
|
|
.create = logfs_create,
|
|
.link = logfs_link,
|
|
.lookup = logfs_lookup,
|
|
.mkdir = logfs_mkdir,
|
|
.mknod = logfs_mknod,
|
|
.rename = logfs_rename,
|
|
.rmdir = logfs_rmdir,
|
|
.symlink = logfs_symlink,
|
|
.unlink = logfs_unlink,
|
|
};
|
|
const struct file_operations logfs_dir_fops = {
|
|
.fsync = logfs_fsync,
|
|
.unlocked_ioctl = logfs_ioctl,
|
|
.iterate = logfs_readdir,
|
|
.read = generic_read_dir,
|
|
.llseek = default_llseek,
|
|
};
|