simple_lookup(): just set DCACHE_DONTCACHE

Browse source

No need to mess with ->d_op at all.  Note that ->d_delete that always
returns 1 is equivalent to having DCACHE_DONTCACHE in ->d_flags.
Later the same thing will be placed into ->s_d_flags of the filesystems
where we want that behaviour for all dentries; then the check in
simple_lookup() will at least get unlikely() slapped on it.

NOTE: there are only two filesystems where
	* simple_lookup() might be called
	* default ->d_op is non-NULL
	* its ->d_delete() doesn't always return 1
If not for those, we could have simple_lookup() just set DCACHE_DONTCACHE
without even looking at ->d_op.  Filesystems in question are btrfs
and tracefs; both have ->d_delete() returning 1 on anything fed to
simple_lookup(), so both would be fine with simple_lookup() setting
DCACHE_DONTCACHE regardless of ->d_op.

IOW, we might want to drop the check for ->d_op in simple_lookup();
it's definitely a separate story, though.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

...

This commit is contained in:

Al Viro 2025-02-23 20:04:30 -05:00

parent d9b13cdad8

commit a97dc087da

1 changed files with 5 additions and 3 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

8

fs/libfs.c

View file