2022-08-05 13:26:27

by Jiachen Zhang

[permalink] [raw]
Subject: [PATCH] fuse: invalidate dentry on EEXIST creates or ENOENT deletes

If kernel creates a file which already exists on the server (EEXIST), we'd
better invalidate its negative dentry cache. Similarly, if kernel wants
to delete a file that is already deleted on the server (ENOENT), we can
also invalidate its positive dentry cache. This commit does this by
setting the fuse dentry timeout to 0 using fuse_invalidate_entry().

Signed-off-by: Jiachen Zhang <[email protected]>
---
fs/fuse/dir.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 74303d6e987b..3bb34a849831 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -669,7 +669,8 @@ static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
if (err == -ENOSYS) {
fc->no_create = 1;
goto mknod;
- }
+ } else if (err == -EEXIST)
+ fuse_invalidate_entry(entry);
out_dput:
dput(res);
return err;
@@ -758,6 +759,8 @@ static int create_new_entry(struct fuse_mount *fm, struct fuse_args *args,
return 0;

out_put_forget_req:
+ if (err == -EEXIST)
+ fuse_invalidate_entry(entry);
kfree(forget);
return err;
}
@@ -892,7 +895,7 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry)
if (!err) {
fuse_dir_changed(dir);
fuse_entry_unlinked(entry);
- } else if (err == -EINTR)
+ } else if (err == -EINTR || err == -ENOENT)
fuse_invalidate_entry(entry);
return err;
}
@@ -915,7 +918,7 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry)
if (!err) {
fuse_dir_changed(dir);
fuse_entry_unlinked(entry);
- } else if (err == -EINTR)
+ } else if (err == -EINTR || err == -ENOENT)
fuse_invalidate_entry(entry);
return err;
}
@@ -956,7 +959,7 @@ static int fuse_rename_common(struct inode *olddir, struct dentry *oldent,
/* newent will end up negative */
if (!(flags & RENAME_EXCHANGE) && d_really_is_positive(newent))
fuse_entry_unlinked(newent);
- } else if (err == -EINTR) {
+ } else if (err == -EINTR || err == -ENOENT) {
/* If request was interrupted, DEITY only knows if the
rename actually took place. If the invalidation
fails (e.g. some process has CWD under the renamed
--
2.20.1