linux-hardened/fs/btrfs
Goldwyn Rodrigues ff0fa73247 btrfs: nowait aio: Correct assignment of pos
Assigning pos for usage early messes up in append mode, where the pos is
re-assigned in generic_write_checks(). Assign pos later to get the
correct position to write from iocb->ki_pos.

Since check_can_nocow also uses the value of pos, we shift
generic_write_checks() before check_can_nocow(). Checks with IOCB_DIRECT
are present in generic_write_checks(), so checking for IOCB_NOWAIT is
enough.

Also, put locking sequence in the fast path.

This fixes a user visible bug, as reported:

"apparently breaks several shell related features on my system.
In zsh history stopped working, because no new entries are added
anymore.
I fist noticed the issue when I tried to build mplayer. It uses a shell
script to generate a help_mp.h file:
[...]

Here is a simple testcase:

 % echo "foo" >> test
 % echo "foo" >> test
 % cat test
 foo
 %
"

Fixes: edf064e7c6 ("btrfs: nowait aio support")
CC: Jens Axboe <axboe@kernel.dk>
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Link: https://lkml.kernel.org/r/20170704042306.GA274@x4
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-07-10 15:29:44 +02:00
..
tests btrfs: remove unused qgroup members from btrfs_trans_handle 2017-04-18 14:07:25 +02:00
acl.c posix_acl: Clear SGID bit when setting file permissions 2016-09-22 10:55:32 +02:00
async-thread.c btrfs: fix crash when tracepoint arguments are freed by wq callbacks 2017-01-09 11:24:50 +01:00
async-thread.h btrfs: limit async_work allocation and worker func duration 2016-12-13 11:01:30 -08:00
backref.c btrfs: replace hardcoded value with SEQ_LAST macro 2017-04-18 14:07:25 +02:00
backref.h
btrfs_inode.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
check-integrity.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
check-integrity.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
compression.c btrfs: use new block error code 2017-06-21 07:47:34 -06:00
compression.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
ctree.c Merge branch 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-05-10 08:33:17 -07:00
ctree.h Linux 4.12-rc5 2017-06-12 08:30:13 -06:00
dedupe.h btrfs: expand cow_file_range() to support in-band dedup and subpage-blocksize 2016-07-26 13:52:25 +02:00
delayed-inode.c btrfs: convert btrfs_delayed_item.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
delayed-inode.h btrfs: convert btrfs_delayed_item.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
delayed-ref.c btrfs: convert btrfs_delayed_ref_node.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
delayed-ref.h btrfs: convert btrfs_delayed_ref_node.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
dev-replace.c Btrfs: switch to div64_u64 if with a u64 divisor 2017-04-18 14:07:26 +02:00
dev-replace.h btrfs: constify device path passed to relevant helpers 2017-02-28 14:26:07 +01:00
dir-item.c btrfs: tree-log.c: Wrong printk information about namelen 2017-06-09 12:48:07 -07:00
disk-io.c Linux 4.12-rc5 2017-06-12 08:30:13 -06:00
disk-io.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
export.c btrfs: Make btrfs_ino take a struct btrfs_inode 2017-02-14 15:50:51 +01:00
export.h
extent-tree.c btrfs: fix race with relocation recovery and fs_root setup 2017-06-01 16:56:55 +02:00
extent_io.c blk: replace bioset_create_nobvec() with a flags arg to bioset_create() 2017-06-18 12:40:59 -06:00
extent_io.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
extent_map.c btrfs: convert extent_map.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
extent_map.h btrfs: convert extent_map.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
file-item.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
file.c btrfs: nowait aio: Correct assignment of pos 2017-07-10 15:29:44 +02:00
free-space-cache.c btrfs: use clear_page where appropriate 2017-04-18 14:07:26 +02:00
free-space-cache.h btrfs: free-space-cache, clean up unnecessary root arguments 2017-02-17 12:03:56 +01:00
free-space-tree.c mm, vmalloc: use __GFP_HIGHMEM implicitly 2017-05-08 17:15:13 -07:00
free-space-tree.h Btrfs: implement the free space B-tree 2015-12-17 12:16:47 -08:00
hash.c btrfs: advertise which crc32c implementation is being used at module load 2016-06-06 14:08:28 +02:00
hash.h btrfs: advertise which crc32c implementation is being used at module load 2016-06-06 14:08:28 +02:00
inode-item.c btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
inode-map.c btrfs: all btrfs_delalloc_release_metadata take btrfs_inode 2017-02-28 11:30:07 +01:00
inode-map.h Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots 2016-01-15 19:25:02 +01:00
inode.c btrfs: nowait aio support 2017-06-20 07:12:03 -06:00
ioctl.c Merge branch 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-05-10 08:33:17 -07:00
Kconfig
locking.c btrfs: cleanup, remove stray return statements 2016-01-07 14:30:52 +01:00
locking.h
lzo.c btrfs: derive maximum output size in the compression implementation 2017-02-28 14:26:36 +01:00
Makefile Btrfs: add free space tree sanity tests 2015-12-17 12:16:47 -08:00
math.h
ordered-data.c btrfs: convert btrfs_ordered_extent.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
ordered-data.h btrfs: convert btrfs_ordered_extent.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
orphan.c
print-tree.c btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
print-tree.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
props.c btrfs: Make btrfs_ino take a struct btrfs_inode 2017-02-14 15:50:51 +01:00
props.h
qgroup.c Merge branch 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-05-10 08:33:17 -07:00
qgroup.h btrfs: qgroup: Re-arrange tracepoint timing to co-operate with reserved space tracepoint 2017-04-18 14:07:26 +02:00
raid56.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
raid56.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
rcu-string.h
reada.c btrfs: remove local blocksize variable in reada_find_extent 2017-04-18 14:07:25 +02:00
relocation.c btrfs: Make btrfs_orphan_add take btrfs_inode 2017-02-28 11:30:10 +01:00
root-tree.c btrfs: Use ktime_get_real_ts for root ctime 2017-04-18 14:07:27 +02:00
scrub.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
send.c Merge branch 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-05-10 08:33:17 -07:00
send.h Btrfs: use linux/sizes.h to represent constants 2016-01-07 14:38:02 +01:00
struct-funcs.c btrfs: fix string and comment grammatical issues and typos 2016-05-25 22:35:14 +02:00
super.c Merge branch 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-05-10 08:33:17 -07:00
sysfs.c btrfs: convert printk(KERN_* to use pr_* calls 2016-09-26 18:08:44 +02:00
sysfs.h btrfs: sysfs: introduce helper for syncing bits with sysfs files 2016-01-21 18:50:40 +01:00
transaction.c btrfs: qgroup: Fix qgroup corruption caused by inode_cache mount option 2017-04-18 14:07:26 +02:00
transaction.h btrfs: remove unused qgroup members from btrfs_trans_handle 2017-04-18 14:07:25 +02:00
tree-defrag.c Btrfs: fix locking bugs when defragging leaves 2015-12-18 02:51:32 +00:00
tree-log.c btrfs: convert extent_map.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
tree-log.h btrfs: Make btrfs_del_inode_ref take btrfs_inode 2017-02-14 15:50:54 +01:00
ulist.c btrfs: ulist: rename ulist_fini to ulist_release 2017-02-17 12:03:50 +01:00
ulist.h btrfs: ulist: rename ulist_fini to ulist_release 2017-02-17 12:03:50 +01:00
uuid-tree.c btrfs: return the actual error value from from btrfs_uuid_tree_iterate 2016-12-19 18:08:15 +01:00
volumes.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
volumes.h btrfs: delete unused member nobarriers 2017-04-18 16:12:07 +02:00
xattr.c btrfs: fix over-80 lines introduced by previous cleanups 2017-02-14 15:50:57 +01:00
xattr.h btrfs: Switch to generic xattr handlers 2016-05-17 19:17:09 -04:00
zlib.c btrfs: derive maximum output size in the compression implementation 2017-02-28 14:26:36 +01:00