| commit | 14b9d0902dfa25dac9c41bf346aa655fdeafe5b2 | [log] [tgz] |
|---|---|---|
| author | David Howells <[email protected]> | Fri Jan 07 10:51:13 2022 +0000 |
| committer | David Howells <[email protected]> | Fri Jan 21 21:36:28 2022 +0000 |
| tree | 7f7d282b76af3da8c6e8cb7d68afddb2ac8a1441 | |
| parent | b64a3314989df8e44c114f377808407f36dbf4f4 [diff] [blame] |
cachefiles: Explain checks in a comment Add a comment to explain the checks that cachefiles is making of the backing filesystem[1]. Suggested-by: Jeff Layton <[email protected]> Signed-off-by: David Howells <[email protected]> Reviewed-by: Jeff Layton <[email protected]> cc: [email protected] Link: https://lore.kernel.org/r/[email protected]/ [1] Link: https://lore.kernel.org/r/164251405621.3435901.771439791811515914.stgit@warthog.procyon.org.uk/ # v1
diff --git a/fs/cachefiles/cache.c b/fs/cachefiles/cache.c index 1e9c7166..2b2879c 100644 --- a/fs/cachefiles/cache.c +++ b/fs/cachefiles/cache.c
@@ -49,7 +49,13 @@ int cachefiles_add_cache(struct cachefiles_cache *cache) goto error_unsupported; } - /* check parameters */ + /* Check features of the backing filesystem: + * - Directories must support looking up and directory creation + * - We use xattrs to store metadata + * - We need to be able to query the amount of space available + * - We want to be able to sync the filesystem when stopping the cache + * - We use DIO to/from pages, so the blocksize mustn't be too big. + */ ret = -EOPNOTSUPP; if (d_is_negative(root) || !d_backing_inode(root)->i_op->lookup ||