linux_dsm_epyc7002/fs
Filipe Manana 8b191a6849 Btrfs: incremental send, check if orphanized dir inode needs delayed rename
If a directory inode is orphanized, because some inode previously
processed has a new name that collides with the old name of the current
inode, we need to check if it needs its rename operation delayed too,
as its ancestor-descendent relationship with some other inode might
have been reversed between the parent and send snapshots and therefore
its rename operation needs to happen after that other inode is renamed.

For example, for the following reproducer where this is needed (provided
by Robbie Ko):

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2

  $ mkdir -p /mnt/data/n1/n2
  $ mkdir /mnt/data/n4
  $ mkdir -p /mnt/data/t6/t7
  $ mkdir /mnt/data/t5
  $ mkdir /mnt/data/t7
  $ mkdir /mnt/data/n4/t2
  $ mkdir /mnt/data/t4
  $ mkdir /mnt/data/t3
  $ mv /mnt/data/t7 /mnt/data/n4/t2
  $ mv /mnt/data/t4 /mnt/data/n4/t2/t7
  $ mv /mnt/data/t5 /mnt/data/n4/t2/t7/t4
  $ mv /mnt/data/t6 /mnt/data/n4/t2/t7/t4/t5
  $ mv /mnt/data/n1/n2 /mnt/data/n4/t2/t7/t4/t5/t6
  $ mv /mnt/data/n1 /mnt/data/n4/t2/t7/t4/t5/t6
  $ mv /mnt/data/n4/t2/t7/t4/t5/t6/t7 /mnt/data/n4/t2/t7/t4/t5/t6/n2
  $ mv /mnt/data/t3 /mnt/data/n4/t2/t7/t4/t5/t6/n2/t7

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/data/n4/t2/t7/t4/t5/t6/n1 /mnt/data/n4
  $ mv /mnt/data/n4/t2 /mnt/data/n4/n1
  $ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6/n2 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/n2/t7/t3 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/t7/t4 /mnt/data/n4/n1/t2/t6
  $ mv /mnt/data/n4/n1/t2/t7 /mnt/data/n4/n1/t2/t3
  $ mv /mnt/data/n4/n1/t2/n2/t7 /mnt/data/n4/n1/t2

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
  ERROR: send ioctl failed with -12: Cannot allocate memory

Where the parent snapshot directory hierarchy is the following:

  .                                                        (ino 256)
  |-- data/                                                (ino 257)
        |-- n4/                                            (ino 260)
             |-- t2/                                       (ino 265)
                  |-- t7/                                  (ino 264)
                       |-- t4/                             (ino 266)
                            |-- t5/                        (ino 263)
                                 |-- t6/                   (ino 261)
                                      |-- n1/              (ino 258)
                                      |-- n2/              (ino 259)
                                           |-- t7/         (ino 262)
                                                |-- t3/    (ino 267)

And the send snapshot's directory hierarchy is the following:

  .                                                        (ino 256)
  |-- data/                                                (ino 257)
        |-- n4/                                            (ino 260)
             |-- n1/                                       (ino 258)
                  |-- t2/                                  (ino 265)
                       |-- n2/                             (ino 259)
                       |-- t3/                             (ino 267)
                       |    |-- t7                         (ino 264)
                       |
                       |-- t6/                             (ino 261)
                       |    |-- t4/                        (ino 266)
                       |         |-- t5/                   (ino 263)
                       |
                       |-- t7/                             (ino 262)

While processing inode 262 we orphanize inode 264 and later attempt
to rename inode 264 to its new name/location, which resulted in building
an incorrect destination path string for the rename operation with the
value "data/n4/t2/t7/t4/t5/t6/n2/t7/t3/t7". This rename operation must
have been done only after inode 267 is processed and renamed, as the
ancestor-descendent relationship between inodes 264 and 267 was reversed
between both snapshots, because otherwise it results in an infinite loop
when building the path string for inode 264 when we are processing an
inode with a number larger than 264. That loop is the following:

  start inode 264, send progress of 265 for example
  parent of 264 -> 267
  parent of 267 -> 262
  parent of 262 -> 259
  parent of 259 -> 261
  parent of 261 -> 263
  parent of 263 -> 266
  parent of 266 -> 264
    |--> back to first iteration while current path string length
         is <= PATH_MAX, and fail with -ENOMEM otherwise

So fix this by making the check if we need to delay a directory rename
regardless of the current inode having been orphanized or not.

A test case for fstests follows soon.

Thanks to Robbie Ko for providing a reproducer for this problem.

Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-06-03 03:10:40 +01:00
..
9p Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
adfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
affs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
afs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
autofs4 VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
befs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
bfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
btrfs Btrfs: incremental send, check if orphanized dir inode needs delayed rename 2015-06-03 03:10:40 +01:00
cachefiles VFS: fs/cachefiles: d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
cifs CIFS: Fix race condition on RFC1002_NEGATIVE_SESSION_RESPONSE 2015-05-20 13:25:55 -05:00
coda VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
configfs configfs: init configfs module earlier at boot time 2015-05-05 17:10:11 -07:00
cramfs
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
devpts VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
dlm
ecryptfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
efivarfs Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-05-06 10:57:37 -07:00
efs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
exofs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
exportfs
ext2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ext3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ext4 ext4: fix an ext3 collapse range regression in xfstests 2015-05-15 00:24:10 -04:00
f2fs f2fs: fix wrong error hanlder in f2fs_follow_link 2015-05-04 14:15:16 -07:00
fat Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
freevxfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
fscache
fuse VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
gfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
hfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
hfsplus Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
hostfs hostfs: Use correct mask for file mode 2015-05-04 14:50:29 +02:00
hpfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
hppfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
hugetlbfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
isofs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
jbd
jbd2 jbd2: fix r_count overflows leading to buffer overflow in journal recovery 2015-05-14 19:11:50 -04:00
jffs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
jfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
kernfs kernfs: do not account ino_ida allocations to memcg 2015-05-14 17:55:51 -07:00
lockd nfsd: eliminate NFSD_DEBUG 2015-04-21 16:16:02 -04:00
logfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
minix VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
ncpfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
nfs nfs: take extra reference to fl->fl_file when running a setlk 2015-05-13 14:56:06 -04:00
nfs_common
nfsd nfsd: skip CB_NULL probes for 4.1 or later 2015-05-04 12:02:42 -04:00
nilfs2 nilfs2: fix sanity check of btree level in nilfs_btree_root_broken() 2015-05-05 17:10:11 -07:00
nls
notify
ntfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
ocfs2 ocfs2: dlm: fix race between purge and get lock resource 2015-05-05 17:10:11 -07:00
omfs omfs: fix potential integer overflow in allocator 2015-05-28 18:25:19 -07:00
openpromfs
overlayfs ovl: mount read-only if workdir can't be created 2015-05-19 14:30:12 +02:00
proc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
pstore Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
qnx4
qnx6 VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
quota Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ramfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
reiserfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
romfs
squashfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
sysfs
sysv VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
tracefs
ubifs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
udf Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ufs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
xfs xfs: fix broken i_nlink accounting for whiteout tmpfile inode 2015-05-29 08:14:55 +10:00
aio.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-16 23:27:56 -04:00
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c
binfmt_elf.c fs/binfmt_elf.c:load_elf_binary(): return -EINVAL on zero-length mappings 2015-05-28 18:25:18 -07:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
binfmt_script.c
block_dev.c direct-io: only inc/dec inode->i_dio_count for file systems 2015-04-24 15:45:28 -04:00
buffer.c page_writeback: clean up mess around cancel_dirty_page() 2015-04-14 16:49:01 -07:00
char_dev.c
compat_binfmt_elf.c
compat_ioctl.c
compat.c
coredump.c
dax.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
dcache.c d_walk() might skip too much 2015-05-28 23:45:30 -04:00
dcookies.c
direct-io.c direct-io: only inc/dec inode->i_dio_count for file systems 2015-04-24 15:45:28 -04:00
drop_caches.c
eventfd.c
eventpoll.c
exec.c parisc,metag: Fix crashes due to stack randomization on stack-grows-upwards architectures 2015-05-12 22:03:44 +02:00
fcntl.c
fhandle.c
file_table.c
file.c mm: rcu-protected get_mm_exe_file() 2015-04-17 09:04:07 -04:00
filesystems.c
fs_pin.c
fs_struct.c
fs-writeback.c
inode.c direct-io: only inc/dec inode->i_dio_count for file systems 2015-04-24 15:45:28 -04:00
internal.h
ioctl.c
Kconfig
Kconfig.binfmt mm: split ET_DYN ASLR from mmap ASLR 2015-04-14 16:49:05 -07:00
libfs.c VFS: fs library helpers: d_inode() annotations 2015-04-15 15:06:58 -04:00
locks.c proc: show locks in /proc/pid/fdinfo/X 2015-04-17 09:04:12 -04:00
Makefile This adds the new tracefs file system. This has been in linux-next for 2015-04-14 10:22:29 -07:00
mbcache.c
mount.h
mpage.c
namei.c path_openat(): fix double fput() 2015-05-09 00:12:48 -04:00
namespace.c mnt: Fix fs_fully_visible to verify the root directory is visible 2015-05-09 11:55:50 -05:00
no-block.c
nsfs.c VFS: assorted weird filesystems: d_inode() annotations 2015-04-15 15:06:58 -04:00
open.c xfs: update for 4.1-rc1 2015-04-24 07:08:41 -07:00
pipe.c VFS: assorted weird filesystems: d_inode() annotations 2015-04-15 15:06:58 -04:00
pnode.c
pnode.h
posix_acl.c VFS: assorted d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
proc_namespace.c
read_write.c
readdir.c
select.c
seq_file.c
signalfd.c
splice.c splice: sendfile() at once fails for big files 2015-05-06 09:27:41 -06:00
stack.c
stat.c VFS: assorted d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
statfs.c
super.c cleancache: remove limit on the number of cleancache enabled filesystems 2015-04-14 16:49:03 -07:00
sync.c
timerfd.c
utimes.c
xattr.c