btrfs: update comment for struct btrfs_inode::lock

[ Upstream commit 68539bd0e7 ]

Update the comment for the lock named "lock" in struct btrfs_inode because
it does not mention that the fields "delalloc_bytes", "defrag_bytes",
"csum_bytes", "outstanding_extents" and "disk_i_size" are also protected
by that lock.

Also add a comment on top of each field protected by this lock to mention
that the lock protects them.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 7ee85f5515 ("btrfs: fix race setting file private on concurrent lseek using same fd")
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Filipe Manana 2023-10-04 11:38:53 +01:00 committed by Greg Kroah-Hartman
parent a0cc053ba1
commit 971d03cd45

View File

@ -82,8 +82,9 @@ struct btrfs_inode {
/* /*
* Lock for counters and all fields used to determine if the inode is in * Lock for counters and all fields used to determine if the inode is in
* the log or not (last_trans, last_sub_trans, last_log_commit, * the log or not (last_trans, last_sub_trans, last_log_commit,
* logged_trans), to access/update new_delalloc_bytes and to update the * logged_trans), to access/update delalloc_bytes, new_delalloc_bytes,
* VFS' inode number of bytes used. * defrag_bytes, disk_i_size, outstanding_extents, csum_bytes and to
* update the VFS' inode number of bytes used.
*/ */
spinlock_t lock; spinlock_t lock;
@ -106,7 +107,7 @@ struct btrfs_inode {
* Counters to keep track of the number of extent item's we may use due * Counters to keep track of the number of extent item's we may use due
* to delalloc and such. outstanding_extents is the number of extent * to delalloc and such. outstanding_extents is the number of extent
* items we think we'll end up using, and reserved_extents is the number * items we think we'll end up using, and reserved_extents is the number
* of extent items we've reserved metadata for. * of extent items we've reserved metadata for. Protected by 'lock'.
*/ */
unsigned outstanding_extents; unsigned outstanding_extents;
@ -130,28 +131,31 @@ struct btrfs_inode {
u64 generation; u64 generation;
/* /*
* transid of the trans_handle that last modified this inode * ID of the transaction handle that last modified this inode.
* Protected by 'lock'.
*/ */
u64 last_trans; u64 last_trans;
/* /*
* transid that last logged this inode * ID of the transaction that last logged this inode.
* Protected by 'lock'.
*/ */
u64 logged_trans; u64 logged_trans;
/* /*
* log transid when this inode was last modified * Log transaction ID when this inode was last modified.
* Protected by 'lock'.
*/ */
int last_sub_trans; int last_sub_trans;
/* a local copy of root's last_log_commit */ /* A local copy of root's last_log_commit. Protected by 'lock'. */
int last_log_commit; int last_log_commit;
union { union {
/* /*
* Total number of bytes pending delalloc, used by stat to * Total number of bytes pending delalloc, used by stat to
* calculate the real block usage of the file. This is used * calculate the real block usage of the file. This is used
* only for files. * only for files. Protected by 'lock'.
*/ */
u64 delalloc_bytes; u64 delalloc_bytes;
/* /*
@ -169,7 +173,7 @@ struct btrfs_inode {
* Total number of bytes pending delalloc that fall within a file * Total number of bytes pending delalloc that fall within a file
* range that is either a hole or beyond EOF (and no prealloc extent * range that is either a hole or beyond EOF (and no prealloc extent
* exists in the range). This is always <= delalloc_bytes and this * exists in the range). This is always <= delalloc_bytes and this
* is used only for files. * is used only for files. Protected by 'lock'.
*/ */
u64 new_delalloc_bytes; u64 new_delalloc_bytes;
/* /*
@ -180,15 +184,15 @@ struct btrfs_inode {
}; };
/* /*
* total number of bytes pending defrag, used by stat to check whether * Total number of bytes pending defrag, used by stat to check whether
* it needs COW. * it needs COW. Protected by 'lock'.
*/ */
u64 defrag_bytes; u64 defrag_bytes;
/* /*
* the size of the file stored in the metadata on disk. data=ordered * The size of the file stored in the metadata on disk. data=ordered
* means the in-memory i_size might be larger than the size on disk * means the in-memory i_size might be larger than the size on disk
* because not all the blocks are written yet. * because not all the blocks are written yet. Protected by 'lock'.
*/ */
u64 disk_i_size; u64 disk_i_size;
@ -222,7 +226,7 @@ struct btrfs_inode {
/* /*
* Number of bytes outstanding that are going to need csums. This is * Number of bytes outstanding that are going to need csums. This is
* used in ENOSPC accounting. * used in ENOSPC accounting. Protected by 'lock'.
*/ */
u64 csum_bytes; u64 csum_bytes;