linux/fs/btrfs
Zhaolei 76a8efa171 btrfs: Continue replace when set_block_ro failed
xfstests/011 failed in node with small_size filesystem.
Can be reproduced by following script:
  DEV_LIST="/dev/vdd /dev/vde"
  DEV_REPLACE="/dev/vdf"

  do_test()
  {
      local mkfs_opt="$1"
      local size="$2"

      dmesg -c >/dev/null
      umount $SCRATCH_MNT &>/dev/null

      echo  mkfs.btrfs -f $mkfs_opt "${DEV_LIST[*]}"
      mkfs.btrfs -f $mkfs_opt "${DEV_LIST[@]}" || return 1
      mount "${DEV_LIST[0]}" $SCRATCH_MNT

      echo -n "Writing big files"
      dd if=/dev/urandom of=$SCRATCH_MNT/t0 bs=1M count=1 >/dev/null 2>&1
      for ((i = 1; i <= size; i++)); do
          echo -n .
          /bin/cp $SCRATCH_MNT/t0 $SCRATCH_MNT/t$i || return 1
      done
      echo

      echo Start replace
      btrfs replace start -Bf "${DEV_LIST[0]}" "$DEV_REPLACE" $SCRATCH_MNT || {
          dmesg
          return 1
      }
      return 0
  }

  # Set size to value near fs size
  # for example, 1897 can trigger this bug in 2.6G device.
  #
  ./do_test "-d raid1 -m raid1" 1897

System will report replace fail with following warning in dmesg:
 [  134.710853] BTRFS: dev_replace from /dev/vdd (devid 1) to /dev/vdf started
 [  135.542390] BTRFS: btrfs_scrub_dev(/dev/vdd, 1, /dev/vdf) failed -28
 [  135.543505] ------------[ cut here ]------------
 [  135.544127] WARNING: CPU: 0 PID: 4080 at fs/btrfs/dev-replace.c:428 btrfs_dev_replace_start+0x398/0x440()
 [  135.545276] Modules linked in:
 [  135.545681] CPU: 0 PID: 4080 Comm: btrfs Not tainted 4.3.0 #256
 [  135.546439] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014
 [  135.547798]  ffffffff81c5bfcf ffff88003cbb3d28 ffffffff817fe7b5 0000000000000000
 [  135.548774]  ffff88003cbb3d60 ffffffff810a88f1 ffff88002b030000 00000000ffffffe4
 [  135.549774]  ffff88003c080000 ffff88003c082588 ffff88003c28ab60 ffff88003cbb3d70
 [  135.550758] Call Trace:
 [  135.551086]  [<ffffffff817fe7b5>] dump_stack+0x44/0x55
 [  135.551737]  [<ffffffff810a88f1>] warn_slowpath_common+0x81/0xc0
 [  135.552487]  [<ffffffff810a89e5>] warn_slowpath_null+0x15/0x20
 [  135.553211]  [<ffffffff81448c88>] btrfs_dev_replace_start+0x398/0x440
 [  135.554051]  [<ffffffff81412c3e>] btrfs_ioctl+0x1d2e/0x25c0
 [  135.554722]  [<ffffffff8114c7ba>] ? __audit_syscall_entry+0xaa/0xf0
 [  135.555506]  [<ffffffff8111ab36>] ? current_kernel_time64+0x56/0xa0
 [  135.556304]  [<ffffffff81201e3d>] do_vfs_ioctl+0x30d/0x580
 [  135.557009]  [<ffffffff8114c7ba>] ? __audit_syscall_entry+0xaa/0xf0
 [  135.557855]  [<ffffffff810011d1>] ? do_audit_syscall_entry+0x61/0x70
 [  135.558669]  [<ffffffff8120d1c1>] ? __fget_light+0x61/0x90
 [  135.559374]  [<ffffffff81202124>] SyS_ioctl+0x74/0x80
 [  135.559987]  [<ffffffff81809857>] entry_SYSCALL_64_fastpath+0x12/0x6f
 [  135.560842] ---[ end trace 2a5c1fc3205abbdd ]---

Reason:
 When big data writen to fs, the whole free space will be allocated
 for data chunk.
 And operation as scrub need to set_block_ro(), and when there is
 only one metadata chunk in system(or other metadata chunks
 are all full), the function will try to allocate a new chunk,
 and failed because no space in device.

Fix:
 When set_block_ro failed for metadata chunk, it is not a problem
 because scrub_lock paused commit_trancaction in same time, and
 metadata are always cowed, so the on-the-fly writepages will not
 write data into same place with scrub/replace.
 Let replace continue in this case is no problem.

Tested by above script, and xfstests/011, plus 100 times xfstests/070.

Changelog v1->v2:
1: Add detail comments in source and commit-message.
2: Add dmesg detail into commit-message.
3: Limit return value of -ENOSPC to be passed.
All suggested by: Filipe Manana <fdmanana@gmail.com>

Suggested-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:51 -08:00
..
tests Btrfs: tests: checking for NULL instead of IS_ERR() 2015-11-25 05:19:50 -08:00
acl.c btrfs: remove useless ACL check 2014-06-09 17:20:42 -07:00
async-thread.c btrfs: async_thread: Fix workqueue 'max_active' value when initializing 2015-08-31 11:46:40 -07:00
async-thread.h btrfs: async_thread: Fix workqueue 'max_active' value when initializing 2015-08-31 11:46:40 -07:00
backref.c btrfs: fix use after free iterating extrefs 2015-10-26 19:38:28 -07:00
backref.h btrfs: cleanup, remove inode_item_info helper 2015-01-14 19:23:47 +01:00
btrfs_inode.h Btrfs: Direct I/O: Fix space accounting 2015-09-21 13:47:55 -07:00
check-integrity.c Merge branch 'cleanups/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 2015-10-21 18:21:40 -07:00
check-integrity.h block: submit_bio_wait() conversions 2013-11-24 16:33:41 -07:00
compression.c Merge branch 'cleanups/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 2015-10-21 18:21:40 -07:00
compression.h btrfs: constify structs with op functions or static definitions 2015-02-16 18:48:44 +01:00
ctree.c Merge branch 'cleanups/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 2015-10-21 18:21:40 -07:00
ctree.h Btrfs: fix the number of transaction units needed to remove a block group 2015-11-25 05:19:50 -08:00
delayed-inode.c btrfs: comment the rest of implicit barriers before waitqueue_active 2015-10-10 18:42:00 +02:00
delayed-inode.h Btrfs: introduce the delayed inode ref deletion for the single link inode 2014-01-28 13:20:09 -08:00
delayed-ref.c btrfs: qgroup: Fix a race in delayed_ref which leads to abort trans 2015-10-26 19:44:39 -07:00
delayed-ref.h btrfs: qgroup: Fix a race in delayed_ref which leads to abort trans 2015-10-26 19:44:39 -07:00
dev-replace.c Merge branch 'fix/waitqueue-barriers' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 2015-10-12 16:24:40 -07:00
dev-replace.h
dir-item.c Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
disk-io.c btrfs: qgroup: exit the rescan worker during umount 2015-11-05 10:32:20 +00:00
disk-io.h Btrfs: add btrfs_read_dev_one_super() to read one specific SB 2015-10-01 17:29:38 +02:00
export.c BTRFS: support NFSv2 export 2015-10-06 06:55:23 -07:00
export.h
extent_io.c btrfs: extent_io: Introduce new function clear_record_extent_bits() 2015-10-21 18:37:44 -07:00
extent_io.h btrfs: qgroup: Introduce btrfs_qgroup_reserve_data function 2015-10-21 18:37:45 -07:00
extent_map.c Btrfs: do not move em to modified list when unpinning 2014-11-21 11:59:54 -08:00
extent_map.h Btrfs: fix NULL pointer crash when running balance and scrub concurrently 2014-06-19 14:20:55 -07:00
extent-tree.c Btrfs: fix the number of transaction units needed to remove a block group 2015-11-25 05:19:50 -08:00
extent-tree.h btrfs: qgroup: Add new qgroup calculation function 2015-06-10 09:25:49 -07:00
file-item.c Merge branch 'cleanups-post-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.1 2015-03-25 10:52:48 -07:00
file.c btrfs: fix signed overflows in btrfs_sync_file 2015-11-25 05:19:50 -08:00
free-space-cache.c Btrfs: don't do extra bitmap search in one bit case 2015-10-21 18:55:41 -07:00
free-space-cache.h Btrfs: keep track of largest extent in bitmaps 2015-10-21 18:55:40 -07:00
hash.c btrfs: LLVMLinux: Remove VLAIS 2014-10-14 10:51:22 +02:00
hash.h Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
inode-item.c Btrfs: consolidate btrfs_error() to btrfs_std_error() 2015-09-29 16:30:00 +02:00
inode-map.c btrfs: qgroup: Cleanup old inaccurate facilities 2015-10-21 18:41:06 -07:00
inode-map.h
inode.c Btrfs: use global reserve when deleting unused block group after ENOSPC 2015-11-25 05:19:50 -08:00
ioctl.c btrfs: check unsupported filters in balance arguments 2015-10-26 19:38:26 -07:00
Kconfig rcu: Make SRCU optional by using CONFIG_SRCU 2015-01-06 11:04:29 -08:00
locking.c btrfs: comment the rest of implicit barriers before waitqueue_active 2015-10-10 18:42:00 +02:00
locking.h btrfs: fix lockups from btrfs_clear_path_blocking 2014-11-19 10:34:35 -08:00
lzo.c btrfs: constify structs with op functions or static definitions 2015-02-16 18:48:44 +01:00
Makefile Btrfs: add sanity tests for new qgroup accounting code 2014-06-09 17:20:49 -07:00
math.h btrfs: cleanup 64bit/32bit divs, compile time constants 2015-03-03 17:23:57 +01:00
ordered-data.c Btrfs: change how we wait for pending ordered extents 2015-10-21 18:51:40 -07:00
ordered-data.h Btrfs: change how we wait for pending ordered extents 2015-10-21 18:51:40 -07:00
orphan.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
print-tree.c btrfs: remove parameter blocksize from read_tree_block 2014-10-02 17:14:50 +02:00
print-tree.h
props.c btrfs: cleanup iterating over prop_handlers array 2015-10-21 18:28:48 +02:00
props.h Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
qgroup.c Btrfs: fix sleeping inside atomic context in qgroup rescan worker 2015-11-05 11:02:22 +00:00
qgroup.h btrfs: qgroup: Check if qgroup reserved space leaked 2015-10-21 18:41:10 -07:00
raid56.c btrfs: comment waitqueue_active implied by locks 2015-10-10 18:35:10 +02:00
raid56.h Btrfs: add RAID 5/6 BTRFS_RBIO_REBUILD_MISSING operation 2015-08-09 07:34:26 -07:00
rcu-string.h
reada.c btrfs: reada: Fix returned errno code 2015-10-21 18:29:50 +02:00
relocation.c Btrfs: fix regression running delayed references when using qgroups 2015-10-25 19:53:26 +00:00
root-tree.c Merge branch 'cleanups/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 2015-10-21 18:21:40 -07:00
scrub.c btrfs: Continue replace when set_block_ro failed 2015-11-25 05:19:51 -08:00
send.c btrfs: fix resending received snapshot with parent 2015-10-13 20:04:10 +01:00
send.h
struct-funcs.c
super.c Btrfs: add fragment=* debug mount option 2015-10-21 18:51:43 -07:00
sysfs.c Btrfs: rename super_kobj to fsid_kobj 2015-09-29 16:29:59 +02:00
sysfs.h Btrfs: rename btrfs_kobj_rm_device to btrfs_sysfs_rm_device_link 2015-09-29 16:29:59 +02:00
transaction.c Btrfs: use global reserve when deleting unused block group after ENOSPC 2015-11-25 05:19:50 -08:00
transaction.h Btrfs: use global reserve when deleting unused block group after ENOSPC 2015-11-25 05:19:50 -08:00
tree-defrag.c Btrfs: cleanup: remove unnecessary check before btrfs_free_path is called 2015-08-31 11:46:41 -07:00
tree-log.c Btrfs: fix regression running delayed references when using qgroups 2015-10-25 19:53:26 +00:00
tree-log.h Btrfs: fix metadata inconsistencies after directory fsync 2015-03-26 17:56:23 -07:00
ulist.c btrfs: ulist: Add ulist_del() function. 2015-06-10 09:26:17 -07:00
ulist.h btrfs: ulist: Add ulist_del() function. 2015-06-10 09:26:17 -07:00
uuid-tree.c Btrfs: make btrfs_search_forward return with nodes unlocked 2014-09-17 13:38:02 -07:00
volumes.c Btrfs: fix the number of transaction units needed to remove a block group 2015-11-25 05:19:50 -08:00
volumes.h btrfs: fix clashing number of the enhanced balance usage filter 2015-11-25 05:19:50 -08:00
xattr.c Btrfs: fix race when listing an inode's xattrs 2015-11-09 18:34:40 +00:00
xattr.h btrfs: use generic posix ACL infrastructure 2014-01-25 23:58:18 -05:00
zlib.c btrfs: constify structs with op functions or static definitions 2015-02-16 18:48:44 +01:00