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40e7efe057
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Qu Wenruo 40e7efe057 btrfs: populate extent_map::generation when reading from disk 
When btrfs_get_extent() tries to get some file extent from disk, it
never populates extent_map::generation, leaving the value to be 0.

On the other hand, for extent map generated by IO, it will get its
generation properly set at finish_ordered_io()

 finish_ordered_io()
 |- unpin_extent_cache(gen = trans->transid)
    |- em->generation = gen;

[CAUSE]
Since extent_map::generation is mostly used by fsync code, and for fsync
they only care about modified extents, which all have their
em::generation > 0.

Thus it's fine to not populate em read from disk for fsync.

[CORNER CASE]
However autodefrag also relies on em::generation to determine if one
extent needs to be defragged.

This unpopulated extent_map::generation can prevent the following
autodefrag case from working:

	mkfs.btrfs -f $dev
	mount $dev $mnt -o autodefrag

	# initial write to queue the inode for autodefrag
	xfs_io -f -c "pwrite 0 4k" $mnt/file
	sync

	# Real fragmented write
	xfs_io -f -s -c "pwrite -b 4096 0 32k" $mnt/file
	sync
	echo "=== before autodefrag ==="
	xfs_io -c "fiemap -v" $mnt/file

	# Drop cache to force em to be read from disk
	echo 3 > /proc/sys/vm/drop_caches
	mount -o remount,commit=1 $mnt
	sleep 3
	sync

	echo "=== After autodefrag ==="
	xfs_io -c "fiemap -v" $mnt/file
	umount $mnt

The result looks like this:

  === before autodefrag ===
  /mnt/btrfs/file:
   EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
     0: [0..15]:         26672..26687        16   0x0
     1: [16..31]:        26656..26671        16   0x0
     2: [32..47]:        26640..26655        16   0x0
     3: [48..63]:        26624..26639        16   0x1
  === After autodefrag ===
  /mnt/btrfs/file:
   EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
     0: [0..15]:         26672..26687        16   0x0
     1: [16..31]:        26656..26671        16   0x0
     2: [32..47]:        26640..26655        16   0x0
     3: [48..63]:        26624..26639        16   0x1

This fragmented 32K will not be defragged by autodefrag.

[FIX]
To make things less weird, just populate extent_map::generation when
reading file extents from disk.

This would make above fragmented extents to be properly defragged:

  == before autodefrag ===
  /mnt/btrfs/file:
   EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
     0: [0..15]:         26672..26687        16   0x0
     1: [16..31]:        26656..26671        16   0x0
     2: [32..47]:        26640..26655        16   0x0
     3: [48..63]:        26624..26639        16   0x1
  === After autodefrag ===
  /mnt/btrfs/file:
   EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
     0: [0..63]:         26688..26751        64   0x1

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:50 +01:00
..
9p Revert "fs/9p: search open fids first" 2022-01-30 22:13:37 +09:00
adfs fs/adfs: remove unneeded variable make code cleaner 2022-01-20 08:52:55 +02:00
affs affs: use bdev_nr_sectors instead of open coding it 2021-10-18 14:43:22 -06:00
afs afs: Fix potential thrashing in afs writeback 2022-03-11 10:24:37 -08:00
autofs autofs: fix wait name hash calculation in autofs_wait() 2021-10-20 21:09:02 -04:00
befs isystem: ship and use stdarg.h 2021-08-19 09:02:55 +09:00
bfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
btrfs btrfs: populate extent_map::generation when reading from disk 2022-03-14 13:13:50 +01:00
cachefiles cachefiles: Fix volume coherency attribute 2022-03-11 10:24:37 -08:00
ceph ceph: set pool_ns in new inode layout for async creates 2022-01-26 20:17:50 +01:00
cifs cifs: fix confusing unneeded warning message on smb2.1 and earlier 2022-02-16 17:16:49 -06:00
coda coda: bump module version to 7.2 2021-11-09 10:02:51 -08:00
configfs configfs: fix a race in configfs_{,un}register_subsystem() 2022-02-22 18:30:28 +01:00
cramfs cramfs: use bdev_nr_bytes instead of open coding it 2021-10-18 14:43:22 -06:00
crypto fscrypt: improve a few comments 2021-10-25 19:11:50 -07:00
debugfs debugfs: lockdown: Allow reading debugfs files that are not world readable 2022-01-06 15:47:41 +01:00
devpts fsnotify: fix fsnotify hooks in pseudo filesystems 2022-01-24 14:17:02 +01:00
dlm driver core changes for 5.17-rc1 2022-01-12 11:11:34 -08:00
ecryptfs fs: add is_idmapped_mnt() helper 2021-12-03 18:44:06 +01:00
efivarfs
efs
erofs erofs: fix ztailpacking on > 4GiB filesystems 2022-03-02 21:58:45 +08:00
exfat exfat: fix missing REQ_SYNC in exfat_update_bhs() 2022-01-10 11:00:04 +09:00
exportfs
ext2 fsdax: shift partition offset handling into the file systems 2021-12-04 08:58:54 -08:00
ext4 Various bug fixes for ext4 fast commit and inline data handling. Also 2022-02-06 10:34:45 -08:00
f2fs Fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into the 2022-02-01 11:13:24 -08:00
fat FAT: use io_schedule_timeout() instead of congestion_wait() 2022-01-20 08:52:54 +02:00
freevxfs
fscache fscache: Fix the volume collision wait condition 2022-01-21 21:36:28 +00:00
fuse fuse: fix pipe buffer lifetime for direct_io 2022-03-07 16:30:44 +01:00
gfs2 gfs2 fixes: 2022-02-11 11:36:32 -08:00
hfs Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
hfsplus hfsplus: use struct_group_attr() for memcpy() region 2022-01-20 08:52:54 +02:00
hostfs hostfs: Fix writeback of dirty pages 2021-12-21 21:44:27 +01:00
hpfs treewide: Replace open-coded flex arrays in unions 2021-10-18 12:28:53 -07:00
hugetlbfs hugetlbfs: fix off-by-one error in hugetlb_vmdelete_list() 2022-01-15 16:30:30 +02:00
iomap xfs, iomap: limit individual ioend chain lengths in writeback 2022-01-26 09:19:20 -08:00
isofs isofs: Fix out of bound access for corrupted isofs image 2021-10-19 12:51:02 +02:00
jbd2 Various bug fixes for ext4 fast commit and inline data handling. Also 2022-02-06 10:34:45 -08:00
jffs2 Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2022-01-17 05:49:30 +02:00
jfs Just one JFS patch 2021-11-03 09:23:25 -07:00
kernfs kernfs: prevent early freeing of root node 2021-12-03 14:36:21 +01:00
ksmbd ksmbd: add support for key exchange 2022-02-04 00:12:22 -06:00
lockd Notable bug fixes: 2022-02-02 10:14:31 -08:00
minix mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
netfs netfs: Make ops->init_rreq() optional 2022-01-21 21:36:28 +00:00
nfs NFS: Do not report writeback errors in nfs_getattr() 2022-02-16 15:15:22 -05:00
nfs_common nfs: Fix kerneldoc warning shown up by W=1 2021-10-04 22:02:17 +01:00
nfsd Notable bug fixes: 2022-02-09 09:56:57 -08:00
nilfs2 Merge branch 'akpm' (patches from Andrew) 2022-01-20 10:41:01 +02:00
nls
notify fanotify: Fix stale file descriptor in copy_event_to_user() 2022-02-01 12:52:07 +01:00
ntfs fs/ntfs/attrib.c: fix one kernel-doc comment 2022-01-15 16:30:24 +02:00
ntfs3 mm: remove cleancache 2022-01-22 08:33:38 +02:00
ocfs2 ocfs2: fix a deadlock when commit trans 2022-01-30 09:56:58 +02:00
omfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
openpromfs
orangefs orangefs: Fix the size of a memory allocation in orangefs_bufmap_alloc() 2021-12-31 14:37:43 -05:00
overlayfs overlayfs fixes for 5.17-rc3 2022-02-01 11:23:02 -08:00
proc proc: fix documentation and description of pagemap 2022-03-05 11:08:33 -08:00
pstore pstore update for v5.17-rc1 2022-01-10 11:48:37 -08:00
qnx4 qnx4: work around gcc false positive warning bug 2021-09-21 08:36:48 -07:00
qnx6
quota quota: make dquot_quota_sync return errors from ->sync_fs 2022-01-30 08:59:47 -08:00
ramfs Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
reiserfs reiserfs: don't use congestion_wait() 2021-11-18 11:52:22 +01:00
romfs
smbfs_common smb3: add new defines from protocol specification 2022-01-18 16:50:47 -06:00
squashfs squashfs: provide backing_dev_info in order to disable read-ahead 2022-01-15 16:30:24 +02:00
sysfs fs/sysfs/dir.c: replace S_IRWXU|S_IRUGO|S_IXUGO with 0755 sysfs_create_dir_ns() 2021-10-05 16:35:05 +02:00
sysv sysv: use BUILD_BUG_ON instead of runtime check 2021-11-09 10:02:52 -08:00
tracefs tracefs: Set the group ownership in apply_options() not parse_options() 2022-02-25 21:05:04 -05:00
ubifs ubifs: read-only if LEB may always be taken in ubifs_garbage_collect 2021-12-23 22:30:38 +01:00
udf udf: Restore i_lenAlloc when inode expansion fails 2022-01-24 14:45:02 +01:00
ufs isystem: ship and use stdarg.h 2021-08-19 09:02:55 +09:00
unicode Fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into the 2022-02-01 11:13:24 -08:00
vboxsf vboxfs: fix broken legacy mount signature checking 2021-09-27 11:26:21 -07:00
verity fs-verity: fix signed integer overflow with i_size near S64_MAX 2021-09-22 10:56:34 -07:00
xfs Bug fixes for 5.17-rc4: 2022-02-26 09:53:19 -08:00
zonefs zonefs: add MODULE_ALIAS_FS 2021-12-17 16:56:35 +09:00
aio.c aio: move aio sysctl to aio.c 2022-01-22 08:33:34 +02:00
anon_inodes.c fs: add anon_inode_getfile_secure() similar to anon_inode_getfd_secure() 2021-09-19 22:35:37 -04:00
attr.c fs: handle circular mappings correctly 2021-11-17 09:26:09 +01:00
bad_inode.c vfs: add rcu argument to ->get_acl() callback 2021-08-18 22:08:24 +02:00
binfmt_aout.c binfmt: a.out: Fix bogus semicolon 2021-09-05 10:15:05 -07:00
binfmt_elf_fdpic.c coredump: Limit coredumps to a single thread group 2021-10-08 12:06:02 -05:00
binfmt_elf.c binfmt_elf fix for v5.17-rc7 2022-03-01 11:31:37 -08:00
binfmt_flat.c binfmt: remove in-tree usage of MAP_EXECUTABLE 2021-06-29 10:53:50 -07:00
binfmt_misc.c Fix regression due to "fs: move binfmt_misc sysctl to its own file" 2022-02-09 09:50:02 -08:00
binfmt_script.c
buffer.c fs/buffer: Convert __block_write_begin_int() to take a folio 2021-12-16 15:49:51 -05:00
char_dev.c
compat_binfmt_elf.c
coredump.c fs/coredump: move coredump sysctls into its own file 2022-01-22 08:33:36 +02:00
d_path.c d_path: fix Kernel doc validator complaining 2021-11-06 13:30:32 -07:00
dax.c dax: remove the copy_from_iter and copy_to_iter methods 2021-12-18 08:04:53 -08:00
dcache.c fs: move dcache sysctls to its own file 2022-01-22 08:33:36 +02:00
direct-io.c fs: get rid of the res2 iocb->ki_complete argument 2021-10-25 10:36:24 -06:00
drop_caches.c fs: drop_caches: fix skipping over shadow cache inodes 2021-09-03 09:58:10 -07:00
eventfd.c eventfd: Export eventfd_wake_count to modules 2021-09-06 07:20:56 -04:00
eventpoll.c eventpoll: simplify sysctl declaration with register_sysctl() 2022-01-22 08:33:35 +02:00
exec.c fs/coredump: move coredump sysctls into its own file 2022-01-22 08:33:36 +02:00
fcntl.c Merge branch 'akpm' (patches from Andrew) 2021-09-03 10:08:28 -07:00
fhandle.c
file_table.c fs/file_table: fix adding missing kmemleak_not_leak() 2022-02-17 10:23:19 -08:00
file.c fget: clarify and improve __fget_files() implementation 2021-12-13 10:55:30 -08:00
filesystems.c fs: simplify get_filesystem_list / get_all_fs_names 2021-08-23 01:25:40 -04:00
fs_context.c vfs: fs_context: fix up param length parsing in legacy_parse_param 2022-01-18 09:23:19 +02:00
fs_parser.c fs_parse: allow parameter value to be empty 2021-12-09 14:09:36 -05:00
fs_pin.c
fs_struct.c
fs_types.c
fs-writeback.c fscache rewrite 2022-01-12 13:45:12 -08:00
fsopen.c
init.c
inode.c fs: move inode sysctls to its own file 2022-01-22 08:33:35 +02:00
internal.h fs/buffer: Convert __block_write_begin_int() to take a folio 2021-12-16 15:49:51 -05:00
io_uring.c io_uring: disallow modification of rsrc_data during quiesce 2022-02-22 09:57:32 -07:00
io-wq.c io_uring-5.17-2022-01-21 2022-01-21 16:07:21 +02:00
io-wq.h Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2022-01-17 05:49:30 +02:00
ioctl.c fs/ioctl: remove unnecessary __user annotation 2022-01-15 16:30:25 +02:00
Kconfig ksmbd: add support for key exchange 2022-02-04 00:12:22 -06:00
Kconfig.binfmt binfmt: remove support for em86 (alpha only) 2021-07-25 22:33:03 -07:00
kernel_read_file.c vfs: check fd has read access in kernel_read_file_from_fd() 2021-10-18 20:22:03 -10:00
libfs.c unicode: clean up the Kconfig symbol confusion 2022-01-20 19:57:24 -05:00
locks.c fs: move locking sysctls where they are used 2022-01-22 08:33:36 +02:00
Makefile Fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into the 2022-02-01 11:13:24 -08:00
mbcache.c
mount.h
mpage.c mm: remove cleancache 2022-01-22 08:33:38 +02:00
namei.c \n 2022-01-28 17:51:31 +02:00
namespace.c fs: add kernel doc for mnt_{hold,unhold}_writers() 2022-02-14 08:35:32 +01:00
no-block.c
nsfs.c
open.c fs: support mapped mounts of mapped filesystems 2021-12-05 10:28:57 +01:00
pipe.c watch_queue: Fix lack of barrier/sync/lock between post and read 2022-03-11 10:17:13 -08:00
pnode.c
pnode.h
posix_acl.c fs: support mapped mounts of mapped filesystems 2021-12-05 10:28:57 +01:00
proc_namespace.c fs: add is_idmapped_mnt() helper 2021-12-03 18:44:06 +01:00
read_write.c fs: remove leftover comments from mandatory locking removal 2021-10-26 12:20:50 -04:00
readdir.c
remap_range.c fs: Convert vfs_dedupe_file_range_compare to folios 2022-01-08 00:28:41 -05:00
select.c select: Fix indefinitely sleeping task in poll_schedule_timeout() 2022-01-11 09:03:05 -08:00
seq_file.c seq_file: move seq_escape() to a header 2021-11-09 10:02:52 -08:00
signalfd.c Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2022-01-17 05:49:30 +02:00
splice.c
stack.c
stat.c fs: add generic helper for filling statx attribute flags 2021-08-17 11:47:43 +02:00
statfs.c
super.c vfs: make freeze_super abort when sync_filesystem returns error 2022-01-30 08:59:47 -08:00
sync.c vfs: make sync_filesystem return errors from ->sync_fs 2022-01-30 08:59:47 -08:00
sysctls.c fs: move namespace sysctls and declare fs base directory 2022-01-22 08:33:36 +02:00
timerfd.c timerfd: Provide timerfd_resume() 2021-08-10 17:57:22 +02:00
userfaultfd.c mm: refactor vm_area_struct::anon_vma_name usage code 2022-03-05 11:08:32 -08:00
utimes.c
xattr.c