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xfs: move xfs_file_iomap_begin_delay around
Move xfs_file_iomap_begin_delay near the end of the file next to the other iomap functions to prepare for additional refactoring. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This commit is contained in:
Christoph Hellwig
Darrick J. Wong
parent
690c2a3887
commit
a526c85c22
@ -530,6 +530,340 @@ check_writeio:
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return alloc_blocks;
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}
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int
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xfs_iomap_write_unwritten(
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xfs_inode_t *ip,
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xfs_off_t offset,
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xfs_off_t count,
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bool update_isize)
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{
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xfs_mount_t *mp = ip->i_mount;
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xfs_fileoff_t offset_fsb;
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xfs_filblks_t count_fsb;
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xfs_filblks_t numblks_fsb;
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int nimaps;
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xfs_trans_t *tp;
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xfs_bmbt_irec_t imap;
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struct inode *inode = VFS_I(ip);
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xfs_fsize_t i_size;
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uint resblks;
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int error;
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trace_xfs_unwritten_convert(ip, offset, count);
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offset_fsb = XFS_B_TO_FSBT(mp, offset);
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count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
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count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb);
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/*
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* Reserve enough blocks in this transaction for two complete extent
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* btree splits. We may be converting the middle part of an unwritten
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* extent and in this case we will insert two new extents in the btree
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* each of which could cause a full split.
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*
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* This reservation amount will be used in the first call to
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* xfs_bmbt_split() to select an AG with enough space to satisfy the
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* rest of the operation.
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*/
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resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1;
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do {
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/*
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* Set up a transaction to convert the range of extents
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* from unwritten to real. Do allocations in a loop until
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* we have covered the range passed in.
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*
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* Note that we can't risk to recursing back into the filesystem
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* here as we might be asked to write out the same inode that we
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* complete here and might deadlock on the iolock.
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*/
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error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
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XFS_TRANS_RESERVE, &tp);
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if (error)
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return error;
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xfs_ilock(ip, XFS_ILOCK_EXCL);
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xfs_trans_ijoin(tp, ip, 0);
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/*
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* Modify the unwritten extent state of the buffer.
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*/
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nimaps = 1;
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error = xfs_bmapi_write(tp, ip, offset_fsb, count_fsb,
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XFS_BMAPI_CONVERT, resblks, &imap,
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&nimaps);
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if (error)
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goto error_on_bmapi_transaction;
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/*
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* Log the updated inode size as we go. We have to be careful
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* to only log it up to the actual write offset if it is
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* halfway into a block.
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*/
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i_size = XFS_FSB_TO_B(mp, offset_fsb + count_fsb);
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if (i_size > offset + count)
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i_size = offset + count;
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if (update_isize && i_size > i_size_read(inode))
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i_size_write(inode, i_size);
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i_size = xfs_new_eof(ip, i_size);
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if (i_size) {
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ip->i_d.di_size = i_size;
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xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
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}
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error = xfs_trans_commit(tp);
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xfs_iunlock(ip, XFS_ILOCK_EXCL);
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if (error)
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return error;
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if (unlikely(!xfs_valid_startblock(ip, imap.br_startblock)))
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return xfs_alert_fsblock_zero(ip, &imap);
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if ((numblks_fsb = imap.br_blockcount) == 0) {
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/*
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* The numblks_fsb value should always get
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* smaller, otherwise the loop is stuck.
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*/
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ASSERT(imap.br_blockcount);
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break;
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}
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offset_fsb += numblks_fsb;
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count_fsb -= numblks_fsb;
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} while (count_fsb > 0);
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return 0;
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error_on_bmapi_transaction:
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xfs_trans_cancel(tp);
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xfs_iunlock(ip, XFS_ILOCK_EXCL);
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return error;
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}
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static inline bool
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imap_needs_alloc(
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struct inode *inode,
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struct xfs_bmbt_irec *imap,
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int nimaps)
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{
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return !nimaps ||
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imap->br_startblock == HOLESTARTBLOCK ||
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imap->br_startblock == DELAYSTARTBLOCK ||
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(IS_DAX(inode) && imap->br_state == XFS_EXT_UNWRITTEN);
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}
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static inline bool
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needs_cow_for_zeroing(
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struct xfs_bmbt_irec *imap,
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int nimaps)
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{
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return nimaps &&
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imap->br_startblock != HOLESTARTBLOCK &&
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imap->br_state != XFS_EXT_UNWRITTEN;
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}
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static int
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xfs_ilock_for_iomap(
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struct xfs_inode *ip,
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unsigned flags,
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unsigned *lockmode)
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{
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unsigned mode = XFS_ILOCK_SHARED;
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bool is_write = flags & (IOMAP_WRITE | IOMAP_ZERO);
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/*
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* COW writes may allocate delalloc space or convert unwritten COW
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* extents, so we need to make sure to take the lock exclusively here.
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*/
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if (xfs_is_cow_inode(ip) && is_write) {
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/*
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* FIXME: It could still overwrite on unshared extents and not
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* need allocation.
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*/
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if (flags & IOMAP_NOWAIT)
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return -EAGAIN;
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mode = XFS_ILOCK_EXCL;
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}
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/*
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* Extents not yet cached requires exclusive access, don't block. This
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* is an opencoded xfs_ilock_data_map_shared() call but with
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* non-blocking behaviour.
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*/
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if (!(ip->i_df.if_flags & XFS_IFEXTENTS)) {
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if (flags & IOMAP_NOWAIT)
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return -EAGAIN;
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mode = XFS_ILOCK_EXCL;
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}
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relock:
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if (flags & IOMAP_NOWAIT) {
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if (!xfs_ilock_nowait(ip, mode))
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return -EAGAIN;
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} else {
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xfs_ilock(ip, mode);
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}
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/*
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* The reflink iflag could have changed since the earlier unlocked
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* check, so if we got ILOCK_SHARED for a write and but we're now a
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* reflink inode we have to switch to ILOCK_EXCL and relock.
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*/
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if (mode == XFS_ILOCK_SHARED && is_write && xfs_is_cow_inode(ip)) {
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xfs_iunlock(ip, mode);
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mode = XFS_ILOCK_EXCL;
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goto relock;
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}
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*lockmode = mode;
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return 0;
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}
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static int
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xfs_file_iomap_begin_delay(
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struct inode *inode,
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loff_t offset,
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loff_t count,
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unsigned flags,
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struct iomap *iomap,
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struct iomap *srcmap);
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static int
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xfs_file_iomap_begin(
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struct inode *inode,
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loff_t offset,
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loff_t length,
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unsigned flags,
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struct iomap *iomap,
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struct iomap *srcmap)
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{
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struct xfs_inode *ip = XFS_I(inode);
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struct xfs_mount *mp = ip->i_mount;
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struct xfs_bmbt_irec imap, cmap;
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xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset);
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xfs_fileoff_t end_fsb = xfs_iomap_end_fsb(mp, offset, length);
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int nimaps = 1, error = 0;
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bool shared = false;
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u16 iomap_flags = 0;
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unsigned lockmode;
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ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO));
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if (XFS_FORCED_SHUTDOWN(mp))
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return -EIO;
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if (!(flags & IOMAP_DIRECT) && !IS_DAX(inode) &&
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!xfs_get_extsz_hint(ip)) {
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/* Reserve delalloc blocks for regular writeback. */
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return xfs_file_iomap_begin_delay(inode, offset, length, flags,
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iomap, srcmap);
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}
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/*
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* Lock the inode in the manner required for the specified operation and
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* check for as many conditions that would result in blocking as
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* possible. This removes most of the non-blocking checks from the
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* mapping code below.
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*/
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error = xfs_ilock_for_iomap(ip, flags, &lockmode);
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if (error)
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return error;
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error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap,
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&nimaps, 0);
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if (error)
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goto out_unlock;
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/*
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* Break shared extents if necessary. Checks for non-blocking IO have
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* been done up front, so we don't need to do them here.
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*/
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if (xfs_is_cow_inode(ip)) {
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/* if zeroing doesn't need COW allocation, then we are done. */
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if ((flags & IOMAP_ZERO) &&
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!needs_cow_for_zeroing(&imap, nimaps))
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goto out_found;
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/* may drop and re-acquire the ilock */
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error = xfs_reflink_allocate_cow(ip, &imap, &cmap, &shared,
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&lockmode, flags & IOMAP_DIRECT);
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if (error)
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goto out_unlock;
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if (shared)
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goto out_found_cow;
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end_fsb = imap.br_startoff + imap.br_blockcount;
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length = XFS_FSB_TO_B(mp, end_fsb) - offset;
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}
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/* Don't need to allocate over holes when doing zeroing operations. */
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if (flags & IOMAP_ZERO)
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goto out_found;
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if (!imap_needs_alloc(inode, &imap, nimaps))
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goto out_found;
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/* If nowait is set bail since we are going to make allocations. */
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if (flags & IOMAP_NOWAIT) {
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error = -EAGAIN;
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goto out_unlock;
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}
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/*
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* We cap the maximum length we map to a sane size to keep the chunks
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* of work done where somewhat symmetric with the work writeback does.
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* This is a completely arbitrary number pulled out of thin air as a
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* best guess for initial testing.
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*
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* Note that the values needs to be less than 32-bits wide until the
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* lower level functions are updated.
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*/
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length = min_t(loff_t, length, 1024 * PAGE_SIZE);
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/*
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* xfs_iomap_write_direct() expects the shared lock. It is unlocked on
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* return.
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*/
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if (lockmode == XFS_ILOCK_EXCL)
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xfs_ilock_demote(ip, lockmode);
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error = xfs_iomap_write_direct(ip, offset, length, &imap,
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nimaps);
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if (error)
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return error;
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iomap_flags |= IOMAP_F_NEW;
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trace_xfs_iomap_alloc(ip, offset, length, XFS_DATA_FORK, &imap);
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out_finish:
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/*
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* Writes that span EOF might trigger an IO size update on completion,
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* so consider them to be dirty for the purposes of O_DSYNC even if
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* there is no other metadata changes pending or have been made here.
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*/
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if (offset + length > i_size_read(inode))
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iomap_flags |= IOMAP_F_DIRTY;
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return xfs_bmbt_to_iomap(ip, iomap, &imap, iomap_flags);
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out_found:
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ASSERT(nimaps);
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xfs_iunlock(ip, lockmode);
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trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap);
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goto out_finish;
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out_found_cow:
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xfs_iunlock(ip, lockmode);
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length = XFS_FSB_TO_B(mp, cmap.br_startoff + cmap.br_blockcount);
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trace_xfs_iomap_found(ip, offset, length - offset, XFS_COW_FORK, &cmap);
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if (imap.br_startblock != HOLESTARTBLOCK) {
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error = xfs_bmbt_to_iomap(ip, srcmap, &imap, 0);
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if (error)
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return error;
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}
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return xfs_bmbt_to_iomap(ip, iomap, &cmap, IOMAP_F_SHARED);
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out_unlock:
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xfs_iunlock(ip, lockmode);
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return error;
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}
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static int
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xfs_file_iomap_begin_delay(
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struct inode *inode,
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@ -740,332 +1074,6 @@ found_cow:
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out_unlock:
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xfs_iunlock(ip, XFS_ILOCK_EXCL);
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return error;
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}
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int
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xfs_iomap_write_unwritten(
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xfs_inode_t *ip,
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xfs_off_t offset,
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xfs_off_t count,
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bool update_isize)
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{
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xfs_mount_t *mp = ip->i_mount;
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xfs_fileoff_t offset_fsb;
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xfs_filblks_t count_fsb;
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xfs_filblks_t numblks_fsb;
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int nimaps;
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xfs_trans_t *tp;
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xfs_bmbt_irec_t imap;
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struct inode *inode = VFS_I(ip);
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xfs_fsize_t i_size;
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uint resblks;
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int error;
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trace_xfs_unwritten_convert(ip, offset, count);
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offset_fsb = XFS_B_TO_FSBT(mp, offset);
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count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
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count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb);
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/*
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* Reserve enough blocks in this transaction for two complete extent
|
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* btree splits. We may be converting the middle part of an unwritten
|
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* extent and in this case we will insert two new extents in the btree
|
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* each of which could cause a full split.
|
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*
|
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* This reservation amount will be used in the first call to
|
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* xfs_bmbt_split() to select an AG with enough space to satisfy the
|
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* rest of the operation.
|
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*/
|
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resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1;
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do {
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/*
|
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* Set up a transaction to convert the range of extents
|
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* from unwritten to real. Do allocations in a loop until
|
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* we have covered the range passed in.
|
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*
|
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* Note that we can't risk to recursing back into the filesystem
|
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* here as we might be asked to write out the same inode that we
|
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* complete here and might deadlock on the iolock.
|
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*/
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error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
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XFS_TRANS_RESERVE, &tp);
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if (error)
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return error;
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xfs_ilock(ip, XFS_ILOCK_EXCL);
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xfs_trans_ijoin(tp, ip, 0);
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/*
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* Modify the unwritten extent state of the buffer.
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*/
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nimaps = 1;
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error = xfs_bmapi_write(tp, ip, offset_fsb, count_fsb,
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XFS_BMAPI_CONVERT, resblks, &imap,
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&nimaps);
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if (error)
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goto error_on_bmapi_transaction;
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/*
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* Log the updated inode size as we go. We have to be careful
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* to only log it up to the actual write offset if it is
|
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* halfway into a block.
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*/
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i_size = XFS_FSB_TO_B(mp, offset_fsb + count_fsb);
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if (i_size > offset + count)
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i_size = offset + count;
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if (update_isize && i_size > i_size_read(inode))
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i_size_write(inode, i_size);
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i_size = xfs_new_eof(ip, i_size);
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if (i_size) {
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ip->i_d.di_size = i_size;
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xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
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}
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error = xfs_trans_commit(tp);
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xfs_iunlock(ip, XFS_ILOCK_EXCL);
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if (error)
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return error;
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if (unlikely(!xfs_valid_startblock(ip, imap.br_startblock)))
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return xfs_alert_fsblock_zero(ip, &imap);
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if ((numblks_fsb = imap.br_blockcount) == 0) {
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/*
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* The numblks_fsb value should always get
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* smaller, otherwise the loop is stuck.
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*/
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ASSERT(imap.br_blockcount);
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break;
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}
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offset_fsb += numblks_fsb;
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count_fsb -= numblks_fsb;
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} while (count_fsb > 0);
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return 0;
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error_on_bmapi_transaction:
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xfs_trans_cancel(tp);
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xfs_iunlock(ip, XFS_ILOCK_EXCL);
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return error;
|
||||
}
|
||||
|
||||
static inline bool
|
||||
imap_needs_alloc(
|
||||
struct inode *inode,
|
||||
struct xfs_bmbt_irec *imap,
|
||||
int nimaps)
|
||||
{
|
||||
return !nimaps ||
|
||||
imap->br_startblock == HOLESTARTBLOCK ||
|
||||
imap->br_startblock == DELAYSTARTBLOCK ||
|
||||
(IS_DAX(inode) && imap->br_state == XFS_EXT_UNWRITTEN);
|
||||
}
|
||||
|
||||
static inline bool
|
||||
needs_cow_for_zeroing(
|
||||
struct xfs_bmbt_irec *imap,
|
||||
int nimaps)
|
||||
{
|
||||
return nimaps &&
|
||||
imap->br_startblock != HOLESTARTBLOCK &&
|
||||
imap->br_state != XFS_EXT_UNWRITTEN;
|
||||
}
|
||||
|
||||
static int
|
||||
xfs_ilock_for_iomap(
|
||||
struct xfs_inode *ip,
|
||||
unsigned flags,
|
||||
unsigned *lockmode)
|
||||
{
|
||||
unsigned mode = XFS_ILOCK_SHARED;
|
||||
bool is_write = flags & (IOMAP_WRITE | IOMAP_ZERO);
|
||||
|
||||
/*
|
||||
* COW writes may allocate delalloc space or convert unwritten COW
|
||||
* extents, so we need to make sure to take the lock exclusively here.
|
||||
*/
|
||||
if (xfs_is_cow_inode(ip) && is_write) {
|
||||
/*
|
||||
* FIXME: It could still overwrite on unshared extents and not
|
||||
* need allocation.
|
||||
*/
|
||||
if (flags & IOMAP_NOWAIT)
|
||||
return -EAGAIN;
|
||||
mode = XFS_ILOCK_EXCL;
|
||||
}
|
||||
|
||||
/*
|
||||
* Extents not yet cached requires exclusive access, don't block. This
|
||||
* is an opencoded xfs_ilock_data_map_shared() call but with
|
||||
* non-blocking behaviour.
|
||||
*/
|
||||
if (!(ip->i_df.if_flags & XFS_IFEXTENTS)) {
|
||||
if (flags & IOMAP_NOWAIT)
|
||||
return -EAGAIN;
|
||||
mode = XFS_ILOCK_EXCL;
|
||||
}
|
||||
|
||||
relock:
|
||||
if (flags & IOMAP_NOWAIT) {
|
||||
if (!xfs_ilock_nowait(ip, mode))
|
||||
return -EAGAIN;
|
||||
} else {
|
||||
xfs_ilock(ip, mode);
|
||||
}
|
||||
|
||||
/*
|
||||
* The reflink iflag could have changed since the earlier unlocked
|
||||
* check, so if we got ILOCK_SHARED for a write and but we're now a
|
||||
* reflink inode we have to switch to ILOCK_EXCL and relock.
|
||||
*/
|
||||
if (mode == XFS_ILOCK_SHARED && is_write && xfs_is_cow_inode(ip)) {
|
||||
xfs_iunlock(ip, mode);
|
||||
mode = XFS_ILOCK_EXCL;
|
||||
goto relock;
|
||||
}
|
||||
|
||||
*lockmode = mode;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int
|
||||
xfs_file_iomap_begin(
|
||||
struct inode *inode,
|
||||
loff_t offset,
|
||||
loff_t length,
|
||||
unsigned flags,
|
||||
struct iomap *iomap,
|
||||
struct iomap *srcmap)
|
||||
{
|
||||
struct xfs_inode *ip = XFS_I(inode);
|
||||
struct xfs_mount *mp = ip->i_mount;
|
||||
struct xfs_bmbt_irec imap, cmap;
|
||||
xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset);
|
||||
xfs_fileoff_t end_fsb = xfs_iomap_end_fsb(mp, offset, length);
|
||||
int nimaps = 1, error = 0;
|
||||
bool shared = false;
|
||||
u16 iomap_flags = 0;
|
||||
unsigned lockmode;
|
||||
|
||||
ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO));
|
||||
|
||||
if (XFS_FORCED_SHUTDOWN(mp))
|
||||
return -EIO;
|
||||
|
||||
if (!(flags & IOMAP_DIRECT) && !IS_DAX(inode) &&
|
||||
!xfs_get_extsz_hint(ip)) {
|
||||
/* Reserve delalloc blocks for regular writeback. */
|
||||
return xfs_file_iomap_begin_delay(inode, offset, length, flags,
|
||||
iomap, srcmap);
|
||||
}
|
||||
|
||||
/*
|
||||
* Lock the inode in the manner required for the specified operation and
|
||||
* check for as many conditions that would result in blocking as
|
||||
* possible. This removes most of the non-blocking checks from the
|
||||
* mapping code below.
|
||||
*/
|
||||
error = xfs_ilock_for_iomap(ip, flags, &lockmode);
|
||||
if (error)
|
||||
return error;
|
||||
|
||||
error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap,
|
||||
&nimaps, 0);
|
||||
if (error)
|
||||
goto out_unlock;
|
||||
|
||||
/*
|
||||
* Break shared extents if necessary. Checks for non-blocking IO have
|
||||
* been done up front, so we don't need to do them here.
|
||||
*/
|
||||
if (xfs_is_cow_inode(ip)) {
|
||||
/* if zeroing doesn't need COW allocation, then we are done. */
|
||||
if ((flags & IOMAP_ZERO) &&
|
||||
!needs_cow_for_zeroing(&imap, nimaps))
|
||||
goto out_found;
|
||||
|
||||
/* may drop and re-acquire the ilock */
|
||||
error = xfs_reflink_allocate_cow(ip, &imap, &cmap, &shared,
|
||||
&lockmode, flags & IOMAP_DIRECT);
|
||||
if (error)
|
||||
goto out_unlock;
|
||||
if (shared)
|
||||
goto out_found_cow;
|
||||
end_fsb = imap.br_startoff + imap.br_blockcount;
|
||||
length = XFS_FSB_TO_B(mp, end_fsb) - offset;
|
||||
}
|
||||
|
||||
/* Don't need to allocate over holes when doing zeroing operations. */
|
||||
if (flags & IOMAP_ZERO)
|
||||
goto out_found;
|
||||
|
||||
if (!imap_needs_alloc(inode, &imap, nimaps))
|
||||
goto out_found;
|
||||
|
||||
/* If nowait is set bail since we are going to make allocations. */
|
||||
if (flags & IOMAP_NOWAIT) {
|
||||
error = -EAGAIN;
|
||||
goto out_unlock;
|
||||
}
|
||||
|
||||
/*
|
||||
* We cap the maximum length we map to a sane size to keep the chunks
|
||||
* of work done where somewhat symmetric with the work writeback does.
|
||||
* This is a completely arbitrary number pulled out of thin air as a
|
||||
* best guess for initial testing.
|
||||
*
|
||||
* Note that the values needs to be less than 32-bits wide until the
|
||||
* lower level functions are updated.
|
||||
*/
|
||||
length = min_t(loff_t, length, 1024 * PAGE_SIZE);
|
||||
|
||||
/*
|
||||
* xfs_iomap_write_direct() expects the shared lock. It is unlocked on
|
||||
* return.
|
||||
*/
|
||||
if (lockmode == XFS_ILOCK_EXCL)
|
||||
xfs_ilock_demote(ip, lockmode);
|
||||
error = xfs_iomap_write_direct(ip, offset, length, &imap,
|
||||
nimaps);
|
||||
if (error)
|
||||
return error;
|
||||
|
||||
iomap_flags |= IOMAP_F_NEW;
|
||||
trace_xfs_iomap_alloc(ip, offset, length, XFS_DATA_FORK, &imap);
|
||||
|
||||
out_finish:
|
||||
/*
|
||||
* Writes that span EOF might trigger an IO size update on completion,
|
||||
* so consider them to be dirty for the purposes of O_DSYNC even if
|
||||
* there is no other metadata changes pending or have been made here.
|
||||
*/
|
||||
if (offset + length > i_size_read(inode))
|
||||
iomap_flags |= IOMAP_F_DIRTY;
|
||||
return xfs_bmbt_to_iomap(ip, iomap, &imap, iomap_flags);
|
||||
|
||||
out_found:
|
||||
ASSERT(nimaps);
|
||||
xfs_iunlock(ip, lockmode);
|
||||
trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap);
|
||||
goto out_finish;
|
||||
|
||||
out_found_cow:
|
||||
xfs_iunlock(ip, lockmode);
|
||||
length = XFS_FSB_TO_B(mp, cmap.br_startoff + cmap.br_blockcount);
|
||||
trace_xfs_iomap_found(ip, offset, length - offset, XFS_COW_FORK, &cmap);
|
||||
if (imap.br_startblock != HOLESTARTBLOCK) {
|
||||
error = xfs_bmbt_to_iomap(ip, srcmap, &imap, 0);
|
||||
if (error)
|
||||
return error;
|
||||
}
|
||||
return xfs_bmbt_to_iomap(ip, iomap, &cmap, IOMAP_F_SHARED);
|
||||
|
||||
out_unlock:
|
||||
xfs_iunlock(ip, lockmode);
|
||||
return error;
|
||||
}
|
||||
|
||||
static int
|
||||
|
||||
Loading…
Reference in New Issue
Block a user