linux/fs/xfs
Chandan Babu R d62113303d xfs: Fix false ENOSPC when performing direct write on a delalloc extent in cow fork
On a higly fragmented filesystem a Direct IO write can fail with -ENOSPC error
even though the filesystem has sufficient number of free blocks.

This occurs if the file offset range on which the write operation is being
performed has a delalloc extent in the cow fork and this delalloc extent
begins much before the Direct IO range.

In such a scenario, xfs_reflink_allocate_cow() invokes xfs_bmapi_write() to
allocate the blocks mapped by the delalloc extent. The extent thus allocated
may not cover the beginning of file offset range on which the Direct IO write
was issued. Hence xfs_reflink_allocate_cow() ends up returning -ENOSPC.

The following script reliably recreates the bug described above.

  #!/usr/bin/bash

  device=/dev/loop0
  shortdev=$(basename $device)

  mntpnt=/mnt/
  file1=${mntpnt}/file1
  file2=${mntpnt}/file2
  fragmentedfile=${mntpnt}/fragmentedfile
  punchprog=/root/repos/xfstests-dev/src/punch-alternating

  errortag=/sys/fs/xfs/${shortdev}/errortag/bmap_alloc_minlen_extent

  umount $device > /dev/null 2>&1

  echo "Create FS"
  mkfs.xfs -f -m reflink=1 $device > /dev/null 2>&1
  if [[ $? != 0 ]]; then
  	echo "mkfs failed."
  	exit 1
  fi

  echo "Mount FS"
  mount $device $mntpnt > /dev/null 2>&1
  if [[ $? != 0 ]]; then
  	echo "mount failed."
  	exit 1
  fi

  echo "Create source file"
  xfs_io -f -c "pwrite 0 32M" $file1 > /dev/null 2>&1

  sync

  echo "Create Reflinked file"
  xfs_io -f -c "reflink $file1" $file2 &>/dev/null

  echo "Set cowextsize"
  xfs_io -c "cowextsize 16M" $file1 > /dev/null 2>&1

  echo "Fragment FS"
  xfs_io -f -c "pwrite 0 64M" $fragmentedfile > /dev/null 2>&1
  sync
  $punchprog $fragmentedfile

  echo "Allocate block sized extent from now onwards"
  echo -n 1 > $errortag

  echo "Create 16MiB delalloc extent in CoW fork"
  xfs_io -c "pwrite 0 4k" $file1 > /dev/null 2>&1

  sync

  echo "Direct I/O write at offset 12k"
  xfs_io -d -c "pwrite 12k 8k" $file1

This commit fixes the bug by invoking xfs_bmapi_write() in a loop until disk
blocks are allocated for atleast the starting file offset of the Direct IO
write range.

Fixes: 3c68d44a2b ("xfs: allocate direct I/O COW blocks in iomap_begin")
Reported-and-Root-caused-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: slight editing to make the locking less grody, and fix some style things]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-08-05 17:00:36 -07:00
..
libxfs xfs: Fix typo 'the the' in comment 2022-07-22 10:58:39 -07:00
scrub xfs: fix for variable set but not used warning 2022-07-20 16:40:39 -07:00
Kconfig
kmem.c mm: introduce memalloc_retry_wait() 2022-01-15 16:30:29 +02:00
kmem.h xfs: remove kmem_zone typedef 2021-10-22 16:00:31 -07:00
Makefile xfs: add in-memory iunlink log item 2022-07-14 11:47:42 +10:00
mrlock.h
xfs_acl.c xfs: move xfs_attr_use_log_assist usage out of libxfs 2022-05-27 10:34:04 +10:00
xfs_acl.h xfs: improve __xfs_set_acl 2022-04-26 13:34:42 +10:00
xfs_aops.c Page cache changes for 5.19 2022-05-24 19:55:07 -07:00
xfs_aops.h
xfs_attr_inactive.c xfs: don't leak memory when attr fork loading fails 2022-07-20 16:40:39 -07:00
xfs_attr_item.c xfs: don't hold xattr leaf buffers across transaction rolls 2022-06-29 08:47:56 -07:00
xfs_attr_item.h xfs: share xattr name and value buffers when logging xattr updates 2022-05-23 08:43:46 +10:00
xfs_attr_list.c xfs: use XFS_IFORK_Q to determine the presence of an xattr fork 2022-07-09 15:17:21 -07:00
xfs_bio_io.c Bug fixes for 5.18: 2022-04-01 19:30:44 -07:00
xfs_bmap_item.c xfs: whiteouts release intents that are not in the AIL 2022-05-04 11:46:47 +10:00
xfs_bmap_item.h xfs: rename _zone variables to _cache 2021-10-22 16:04:20 -07:00
xfs_bmap_util.c xfs: fix NULL pointer dereference in xfs_getbmap() 2022-07-31 09:21:27 -07:00
xfs_bmap_util.h xfs: kill the XFS_IOC_{ALLOC,FREE}SP* ioctls 2022-01-17 09:16:41 -08:00
xfs_buf_item_recover.c xfs: convert buf_cancel_table allocation to kmalloc_array 2022-05-27 10:27:19 +10:00
xfs_buf_item.c xfs: log items should have a xlog pointer, not a mount 2022-03-20 08:59:49 -07:00
xfs_buf_item.h xfs: convert buffer log item flags to unsigned. 2022-04-21 10:46:40 +10:00
xfs_buf.c xfs: xfs_buf cache destroy isn't RCU safe 2022-07-20 16:40:39 -07:00
xfs_buf.h xfs: xfs_buf cache destroy isn't RCU safe 2022-07-20 16:40:39 -07:00
xfs_dir2_readdir.c xfs: convert XFS_IFORK_PTR to a static inline helper 2022-07-09 15:17:21 -07:00
xfs_discard.c xfs: pass perag to xfs_alloc_read_agf() 2022-07-07 19:07:40 +10:00
xfs_discard.h
xfs_dquot_item_recover.c xfs: replace xfs_sb_version checks with feature flag checks 2021-08-19 10:07:12 -07:00
xfs_dquot_item.c xfs: remove support for disabling quota accounting on a mounted file system 2021-08-06 11:05:36 -07:00
xfs_dquot_item.h xfs: remove support for disabling quota accounting on a mounted file system 2021-08-06 11:05:36 -07:00
xfs_dquot.c xfs: Fix comment typo 2022-07-22 10:58:39 -07:00
xfs_dquot.h xfs: remove warning counters from struct xfs_dquot_res 2022-05-11 17:12:09 +10:00
xfs_error.c xfs: add leaf to node error tag 2022-05-11 17:01:23 +10:00
xfs_error.h xfs: convert ptag flags to unsigned. 2022-04-21 10:47:25 +10:00
xfs_export.c xfs: convert remaining mount flags to state flags 2021-08-19 10:07:13 -07:00
xfs_export.h
xfs_extent_busy.c xfs: pass perags through to the busy extent code 2021-06-02 10:48:24 +10:00
xfs_extent_busy.h xfs: pass perags through to the busy extent code 2021-06-02 10:48:24 +10:00
xfs_extfree_item.c xfs: delete extra space and tab in blank line 2022-07-31 09:21:27 -07:00
xfs_extfree_item.h xfs: rename _zone variables to _cache 2021-10-22 16:04:20 -07:00
xfs_file.c xfs: check return codes when flushing block devices 2022-08-05 17:00:36 -07:00
xfs_filestream.c xfs: pass perag to xfs_alloc_read_agf() 2022-07-07 19:07:40 +10:00
xfs_filestream.h xfs: convert mount flags to features 2021-08-19 10:07:12 -07:00
xfs_fsmap.c xfs: pass perag to xfs_alloc_read_agf() 2022-07-07 19:07:40 +10:00
xfs_fsmap.h
xfs_fsops.c xfs: Pre-calculate per-AG agbno geometry 2022-07-07 19:13:02 +10:00
xfs_fsops.h
xfs_globals.c xfs: Add larp debug option 2022-05-11 17:01:22 +10:00
xfs_health.c xfs: replace XFS_FORCED_SHUTDOWN with xfs_is_shutdown 2021-08-19 10:07:13 -07:00
xfs_icache.c xfs: don't leak memory when attr fork loading fails 2022-07-20 16:40:39 -07:00
xfs_icache.h xfs: introduce xfs_inodegc_push() 2022-06-23 13:34:38 -07:00
xfs_icreate_item.c xfs: fix potential log item leak 2022-05-04 11:45:11 +10:00
xfs_icreate_item.h xfs: rename _zone variables to _cache 2021-10-22 16:04:20 -07:00
xfs_inode_item_recover.c xfs: hide log iovec alignment constraints 2022-05-04 11:45:50 +10:00
xfs_inode_item.c xfs: replace inode fork size macros with functions 2022-07-12 11:17:27 -07:00
xfs_inode_item.h xfs: aborting inodes on shutdown may need buffer lock 2022-03-29 18:21:59 -07:00
xfs_inode.c xfs: make attr forks permanent 2022-07-14 09:46:37 -07:00
xfs_inode.h xfs: make attr forks permanent 2022-07-14 09:46:37 -07:00
xfs_ioctl32.c xfs: Set up infrastructure for log attribute replay 2022-05-04 12:41:02 +10:00
xfs_ioctl32.h xfs: remove unused xfs_ioctl32.h declarations 2022-01-18 10:18:36 -08:00
xfs_ioctl.c xfs: convert XFS_IFORK_PTR to a static inline helper 2022-07-09 15:17:21 -07:00
xfs_ioctl.h xfs: kill the XFS_IOC_{ALLOC,FREE}SP* ioctls 2022-01-17 09:16:41 -08:00
xfs_iomap.c xfs: replace XFS_IFORK_Q with a proper predicate function 2022-07-12 11:17:27 -07:00
xfs_iomap.h iomap: add a IOMAP_DAX flag 2021-12-04 08:58:53 -08:00
xfs_iops.c xfs: replace XFS_IFORK_Q with a proper predicate function 2022-07-12 11:17:27 -07:00
xfs_iops.h xfs: add selinux labels to whiteout inodes 2022-07-09 10:56:02 -07:00
xfs_itable.c xfs: replace inode fork size macros with functions 2022-07-12 11:17:27 -07:00
xfs_itable.h xfs: Enable bulkstat ioctl to support 64-bit per-inode extent counters 2022-04-13 07:02:45 +00:00
xfs_iunlink_item.c xfs: add in-memory iunlink log item 2022-07-14 11:47:42 +10:00
xfs_iunlink_item.h xfs: add in-memory iunlink log item 2022-07-14 11:47:42 +10:00
xfs_iwalk.c xfs: avoid buffer deadlocks when walking fs inodes 2021-08-09 11:13:16 -07:00
xfs_iwalk.h xfs: Decouple XFS_IBULK flags from XFS_IWALK flags 2022-04-13 07:02:44 +00:00
xfs_linux.h xfs: drop async cache flushes from CIL commits. 2022-03-29 18:22:02 -07:00
xfs_log_cil.c xfs: xlog_sync() manually adjusts grant head space 2022-07-07 18:56:09 +10:00
xfs_log_priv.h xfs: xlog_sync() manually adjusts grant head space 2022-07-07 18:56:09 +10:00
xfs_log_recover.c xfs: double link the unlinked inode list 2022-07-14 11:46:43 +10:00
xfs_log.c xfs: check return codes when flushing block devices 2022-08-05 17:00:36 -07:00
xfs_log.h xfs: move CIL ordering to the logvec chain 2022-07-07 18:56:08 +10:00
xfs_message.c Merge branch 'guilt/xfs-unsigned-flags-5.18' into xfs-5.19-for-next 2022-04-21 16:45:03 +10:00
xfs_message.h xfs: implement per-mount warnings for scrub and shrink usage 2022-05-27 10:31:34 +10:00
xfs_mount.c xfs: Pre-calculate per-AG agbno geometry 2022-07-07 19:13:02 +10:00
xfs_mount.h xfs: bound maximum wait time for inodegc work 2022-06-23 13:34:38 -07:00
xfs_mru_cache.c xfs: rename _zone variables to _cache 2021-10-22 16:04:20 -07:00
xfs_mru_cache.h
xfs_ondisk.h xfs: Set up infrastructure for log attribute replay 2022-05-04 12:41:02 +10:00
xfs_pnfs.c xfs: use setattr_copy to set vfs inode attributes 2022-03-14 10:23:16 -07:00
xfs_pnfs.h
xfs_pwork.c
xfs_pwork.h
xfs_qm_bhv.c xfs: replace xfs_sb_version checks with feature flag checks 2021-08-19 10:07:12 -07:00
xfs_qm_syscalls.c xfs: introduce xfs_inodegc_push() 2022-06-23 13:34:38 -07:00
xfs_qm.c xfs: fix intermittent hang during quotacheck 2022-08-05 17:00:36 -07:00
xfs_qm.h xfs: remove quota warning limit from struct xfs_quota_limits 2022-05-11 17:12:09 +10:00
xfs_quota.h xfs: queue inactivation immediately when quota is nearing enforcement 2021-08-09 10:52:18 -07:00
xfs_quotaops.c xfs: don't set quota warning values 2022-05-11 17:12:09 +10:00
xfs_refcount_item.c xfs: whiteouts release intents that are not in the AIL 2022-05-04 11:46:47 +10:00
xfs_refcount_item.h xfs: rename _zone variables to _cache 2021-10-22 16:04:20 -07:00
xfs_reflink.c xfs: Fix false ENOSPC when performing direct write on a delalloc extent in cow fork 2022-08-05 17:00:36 -07:00
xfs_reflink.h xfs: pass perag to xfs_alloc_read_agf() 2022-07-07 19:07:40 +10:00
xfs_rmap_item.c xfs: whiteouts release intents that are not in the AIL 2022-05-04 11:46:47 +10:00
xfs_rmap_item.h xfs: rename _zone variables to _cache 2021-10-22 16:04:20 -07:00
xfs_rtalloc.c Merge tag 'large-extent-counters-v9' of https://github.com/chandanr/linux into xfs-5.19-for-next 2022-04-21 16:46:17 +10:00
xfs_rtalloc.h xfs: recalculate free rt extents after log recovery 2022-04-12 06:49:42 +10:00
xfs_stats.c
xfs_stats.h
xfs_super.c xfs: xfs_buf cache destroy isn't RCU safe 2022-07-20 16:40:39 -07:00
xfs_super.h xfs: move xfs_attr_use_log_assist out of xfs_log.c 2022-05-27 10:33:29 +10:00
xfs_symlink.c xfs: replace inode fork size macros with functions 2022-07-12 11:17:27 -07:00
xfs_symlink.h
xfs_sysctl.c
xfs_sysctl.h xfs: Add larp debug option 2022-05-11 17:01:22 +10:00
xfs_sysfs.c xfs: Add larp debug option 2022-05-11 17:01:22 +10:00
xfs_sysfs.h
xfs_trace.c xfs: add trace point for fs shutdown 2021-08-18 18:46:00 -07:00
xfs_trace.h xfs: make attr forks permanent 2022-07-14 09:46:37 -07:00
xfs_trans_ail.c xfs: log shutdown triggers should only shut down the log 2022-03-29 18:22:01 -07:00
xfs_trans_buf.c xfs: introduce xfs_buf_daddr() 2021-08-19 10:07:14 -07:00
xfs_trans_dquot.c xfs: remove quota warning limit from struct xfs_quota_limits 2022-05-11 17:12:09 +10:00
xfs_trans_priv.h xfs: convert log vector chain to use list heads 2022-07-07 18:55:59 +10:00
xfs_trans.c xfs: introduce in-memory inode unlink log items 2022-07-14 09:21:42 -07:00
xfs_trans.h xfs: introduce in-memory inode unlink log items 2022-07-14 09:21:42 -07:00
xfs_xattr.c xfs: fix TOCTOU race involving the new logged xattrs control knob 2022-06-15 23:13:32 -07:00
xfs_xattr.h xfs: move xfs_attr_use_log_assist usage out of libxfs 2022-05-27 10:34:04 +10:00
xfs.h