linux/fs/btrfs
Filipe Manana a79c3a99ac btrfs: fix failure of RWF_NOWAIT write into prealloc extent beyond eof
commit 4b1946284d upstream.

If we attempt to write to prealloc extent located after eof using a
RWF_NOWAIT write, we always fail with -EAGAIN.

We do actually check if we have an allocated extent for the write at
the start of btrfs_file_write_iter() through a call to check_can_nocow(),
but later when we go into the actual direct IO write path we simply
return -EAGAIN if the write starts at or beyond EOF.

Trivial to reproduce:

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

  $ touch /mnt/foo
  $ chattr +C /mnt/foo

  $ xfs_io -d -c "pwrite -S 0xab 0 64K" /mnt/foo
  wrote 65536/65536 bytes at offset 0
  64 KiB, 16 ops; 0.0004 sec (135.575 MiB/sec and 34707.1584 ops/sec)

  $ xfs_io -c "falloc -k 64K 1M" /mnt/foo

  $ xfs_io -d -c "pwrite -N -V 1 -S 0xfe -b 64K 64K 64K" /mnt/foo
  pwrite: Resource temporarily unavailable

On xfs and ext4 the write succeeds, as expected.

Fix this by removing the wrong check at btrfs_direct_IO().

Fixes: edf064e7c6 ("btrfs: nowait aio support")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:37:08 -04:00
..
tests btrfs: Correctly handle empty trees in find_first_clear_extent_bit 2020-02-11 04:35:34 -08:00
acl.c btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter 2019-04-29 19:02:44 +02:00
async-thread.c Btrfs: fix crash during unmount due to race with delayed inode workers 2020-04-17 10:50:15 +02:00
async-thread.h Btrfs: fix crash during unmount due to race with delayed inode workers 2020-04-17 10:50:15 +02:00
backref.c Btrfs: fix deadlock between fiemap and transaction commits 2019-07-30 18:25:12 +02:00
backref.h btrfs: fiemap: preallocate ulists for btrfs_check_shared 2019-07-01 13:34:53 +02:00
block-group.c btrfs: fix a block group ref counter leak after failure to remove block group 2020-06-30 15:36:47 -04:00
block-group.h btrfs: move struct io_ctl to free-space-cache.h 2019-09-09 14:59:15 +02:00
block-rsv.c btrfs: force chunk allocation if our global rsv is larger than metadata 2020-06-22 09:31:13 +02:00
block-rsv.h btrfs: migrate the global_block_rsv helpers to block-rsv.c 2019-07-02 12:30:55 +02:00
btrfs_inode.h btrfs: remove assumption about csum type form btrfs_print_data_csum_error() 2019-07-01 13:35:02 +02:00
check-integrity.c btrfs: fix possible NULL-pointer dereference in integrity checks 2020-02-24 08:36:53 +01:00
check-integrity.h btrfs: replace GPL boilerplate by SPDX -- headers 2018-04-12 16:29:46 +02:00
compression.c btrfs: move cond_wake_up functions out of ctree 2019-09-09 14:59:15 +02:00
compression.h btrfs: compression: replace set_level callbacks by a common helper 2019-09-09 14:59:11 +02:00
ctree.c Btrfs: fix race between adding and putting tree mod seq elements and nodes 2020-02-11 04:35:34 -08:00
ctree.h btrfs: check if a log root exists before locking the log_mutex on unlink 2020-06-30 15:37:08 -04:00
delalloc-space.c Btrfs: fix qgroup double free after failure to reserve metadata for delalloc 2019-10-17 20:13:44 +02:00
delalloc-space.h btrfs: migrate the delalloc space stuff to it's own home 2019-07-04 17:26:17 +02:00
delayed-inode.c btrfs: use nofs allocations for running delayed items 2020-04-17 10:50:15 +02:00
delayed-inode.h Btrfs: delayed-inode: use rb_first_cached for ins_root and del_root 2018-10-15 17:23:33 +02:00
delayed-ref.c Btrfs: fix race between adding and putting tree mod seq elements and nodes 2020-02-11 04:35:34 -08:00
delayed-ref.h btrfs: migrate the delayed refs rsv code 2019-07-04 17:26:17 +02:00
dev-replace.c btrfs: move cond_wake_up functions out of ctree 2019-09-09 14:59:15 +02:00
dev-replace.h btrfs: get fs_info from trans in btrfs_run_dev_replace 2019-04-29 19:02:43 +02:00
dir-item.c btrfs: remove unused parameter fs_info from btrfs_extend_item 2019-04-29 19:02:50 +02:00
disk-io.c btrfs: set update the uuid generation as soon as possible 2020-04-17 10:50:15 +02:00
disk-io.h btrfs: Make reada_tree_block_flagged private 2019-09-09 14:59:11 +02:00
export.c btrfs: Remove 'objectid' member from struct btrfs_root 2018-10-15 17:23:25 +02:00
export.h btrfs: replace GPL boilerplate by SPDX -- headers 2018-04-12 16:29:46 +02:00
extent_io.c btrfs: Don't submit any btree write bio if the fs has errors 2020-04-17 10:50:15 +02:00
extent_io.h btrfs: Remove delalloc_end argument from extent_clear_unlock_delalloc 2019-09-09 14:58:59 +02:00
extent_map.c Btrfs: fix race between using extent maps and merging them 2020-02-19 19:53:00 +01:00
extent_map.h btrfs: Remove impossible condition from mergable_maps 2019-02-25 14:13:21 +01:00
extent-tree.c btrfs: handle logged extent failure properly 2020-02-28 17:22:13 +01:00
file-item.c btrfs: do not ignore error from btrfs_next_leaf() when inserting checksums 2020-06-22 09:30:55 +02:00
file.c btrfs: fix missing semaphore unlock in btrfs_sync_file 2020-04-17 10:50:15 +02:00
free-space-cache.c btrfs: check page->mapping when loading free space cache 2019-12-17 19:56:02 +01:00
free-space-cache.h btrfs: move struct io_ctl to free-space-cache.h 2019-09-09 14:59:15 +02:00
free-space-tree.c btrfs: move basic block_group definitions to their own header 2019-09-09 14:59:03 +02:00
free-space-tree.h btrfs: move basic block_group definitions to their own header 2019-09-09 14:59:03 +02:00
inode-item.c btrfs: Make btrfs_find_name_in_ext_backref return struct btrfs_inode_extref 2019-09-09 14:59:16 +02:00
inode-map.c btrfs: qgroup: Always free PREALLOC META reserve in btrfs_delalloc_release_extents() 2019-10-15 18:50:07 +02:00
inode-map.h btrfs: replace GPL boilerplate by SPDX -- headers 2018-04-12 16:29:46 +02:00
inode.c btrfs: fix failure of RWF_NOWAIT write into prealloc extent beyond eof 2020-06-30 15:37:08 -04:00
ioctl.c Btrfs: make deduplication with range including the last block work 2020-02-11 04:35:33 -08:00
Kconfig btrfs: Fix build error while LIBCRC32C is module 2019-07-17 17:03:30 +02:00
locking.c btrfs: move cond_wake_up functions out of ctree 2019-09-09 14:59:15 +02:00
locking.h btrfs: Remove unused locking functions 2019-09-09 14:58:59 +02:00
lzo.c btrfs: compression: replace set_level callbacks by a common helper 2019-09-09 14:59:11 +02:00
Makefile btrfs: migrate the block group lookup code 2019-09-09 14:59:04 +02:00
misc.h btrfs: move math functions to misc.h 2019-09-09 14:59:15 +02:00
ordered-data.c Btrfs: fix btrfs_wait_ordered_range() so that it waits for all ordered extents 2020-02-28 17:22:24 +01:00
ordered-data.h btrfs: don't assume ordered sums to be 4 bytes 2019-07-01 13:35:00 +02:00
orphan.c btrfs: replace GPL boilerplate by SPDX -- sources 2018-04-12 16:29:51 +02:00
print-tree.c btrfs: switch extent_buffer write_locks from atomic to int 2019-07-02 12:30:47 +02:00
print-tree.h btrfs: print-tree: debugging output enhancement 2018-04-20 19:18:16 +02:00
props.c btrfs: rename the btrfs_calc_*_metadata_size helpers 2019-09-09 14:59:13 +02:00
props.h btrfs: delete unused function btrfs_set_prop_trans 2019-04-29 19:02:54 +02:00
qgroup.c btrfs: qgroup: mark qgroup inconsistent if we're inherting snapshot to a new qgroup 2020-06-22 09:31:09 +02:00
qgroup.h btrfs: destroy qgroup extent records on transaction abort 2020-02-28 17:22:23 +01:00
raid56.c btrfs: get rid of unique workqueue helper functions 2020-01-09 10:20:06 +01:00
raid56.h btrfs: constify map parameter for nr_parity_stripes and nr_data_stripes 2019-07-01 13:34:58 +02:00
rcu-string.h btrfs: replace GPL boilerplate by SPDX -- headers 2018-04-12 16:29:46 +02:00
reada.c btrfs: get rid of unique workqueue helper functions 2020-01-09 10:20:06 +01:00
ref-verify.c btrfs: ref-verify: fix memory leaks 2020-02-19 19:53:00 +01:00
ref-verify.h btrfs: ref-verify: Use btrfs_ref to refactor btrfs_ref_tree_mod() 2019-04-29 19:02:49 +02:00
relocation.c btrfs: fix transaction leak in btrfs_recover_relocation 2020-05-06 08:15:05 +02:00
root-tree.c btrfs: do not delete mismatched root refs 2020-01-23 08:22:40 +01:00
scrub.c btrfs: get rid of unique workqueue helper functions 2020-01-09 10:20:06 +01:00
send.c btrfs: send: emit file capabilities after chown 2020-06-22 09:31:12 +02:00
send.h btrfs: replace GPL boilerplate by SPDX -- headers 2018-04-12 16:29:46 +02:00
space-info.c btrfs: improve global reserve stealing logic 2020-06-22 09:31:08 +02:00
space-info.h btrfs: improve global reserve stealing logic 2020-06-22 09:31:08 +02:00
struct-funcs.c btrfs: tie extent buffer and it's token together 2019-09-09 14:59:16 +02:00
super.c btrfs: log message when rw remount is attempted with unclean tree-log 2020-02-19 19:53:01 +01:00
sysfs.c btrfs: sysfs: move helper macros to sysfs.c 2019-09-09 14:59:08 +02:00
sysfs.h btrfs: sysfs: move helper macros to sysfs.c 2019-09-09 14:59:08 +02:00
transaction.c btrfs: force chunk allocation if our global rsv is larger than metadata 2020-06-22 09:31:13 +02:00
transaction.h btrfs: improve global reserve stealing logic 2020-06-22 09:31:08 +02:00
tree-checker.c Btrfs: make tree checker detect checksum items with overlapping ranges 2019-12-31 16:41:55 +01:00
tree-checker.h btrfs: get fs_info from eb in btrfs_check_chunk_valid 2019-04-29 19:02:39 +02:00
tree-defrag.c btrfs: open code now trivial btrfs_set_lock_blocking 2019-02-25 14:13:27 +01:00
tree-log.c btrfs: check if a log root exists before locking the log_mutex on unlink 2020-06-30 15:37:08 -04:00
tree-log.h btrfs: get fs_info from trans in btrfs_set_log_full_commit 2019-04-29 19:02:41 +02:00
ulist.c btrfs: replace GPL boilerplate by SPDX -- sources 2018-04-12 16:29:51 +02:00
ulist.h btrfs: replace GPL boilerplate by SPDX -- headers 2018-04-12 16:29:46 +02:00
uuid-tree.c btrfs: handle ENOENT in btrfs_uuid_tree_iterate 2019-12-31 16:42:05 +01:00
volumes.c btrfs: include non-missing as a qualifier for the latest_bdev 2020-06-22 09:31:12 +02:00
volumes.h btrfs: Remove btrfs_bio::flags member 2019-12-17 19:56:06 +01:00
xattr.c Btrfs: fix failure to persist compression property xattr deletion on fsync 2019-06-17 16:37:17 +02:00
xattr.h btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter 2019-04-29 19:02:44 +02:00
zlib.c btrfs: compression: replace set_level callbacks by a common helper 2019-09-09 14:59:11 +02:00
zstd.c btrfs: move cond_wake_up functions out of ctree 2019-09-09 14:59:15 +02:00