This is just a preparation for the move of the main renameat logic to a separate function to make the logic easier to follow. This change contains the flow changes so that the actual change to move the main logic to a separate function does no change the flow at all. Changes to the flow here: 1. Flags handling is moved into the retry loop. So it can be moved into the function with the main logic. A few extra arithmetic checks on a slow path should be OK. 2. Just like the similar patches for rmdir and others a few commits before, previously on filename_create() and filename_lookup() error the function used to exit immediately, and now it will check the return code to see if ESTALE retry is appropriate. Both filename_create() and filename_lookup() do their own retries on ESTALE (at least via filename_parentat() used inside), but this extra check should be completely fine. Invalid flags will now hit `if retry_estale()` as well. 3. unlikely() is added around the ESTALE check; Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Christian Brauner <christian.brauner@xxxxxxxxxx> Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/io-uring/CAHk-=wiG+sN+2zSoAOggKCGue2kOJvw3rQySvQXsZstRQFTN+g@xxxxxxxxxxxxxx/ Link: https://lore.kernel.org/io-uring/CAHk-=wjFd0qn6asio=zg7zUTRmSty_TpAEhnwym1Qb=wFgCKzA@xxxxxxxxxxxxxx/ Signed-off-by: Dmitry Kadashev <dkadashev@xxxxxxxxx> --- fs/namei.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index b93e9623eb5d..a75abff5a9a6 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4654,9 +4654,9 @@ int do_renameat2(int olddfd, struct filename *from, int newdfd, int old_type, new_type; struct inode *delegated_inode = NULL; unsigned int lookup_flags = 0, target_flags = LOOKUP_RENAME_TARGET; - bool should_retry = false; int error = -EINVAL; +retry: if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) goto put_names; @@ -4667,7 +4667,6 @@ int do_renameat2(int olddfd, struct filename *from, int newdfd, if (flags & RENAME_EXCHANGE) target_flags = 0; -retry: error = __filename_parentat(olddfd, from, lookup_flags, &old_path, &old_last, &old_type); if (error) @@ -4769,17 +4768,14 @@ int do_renameat2(int olddfd, struct filename *from, int newdfd, } mnt_drop_write(old_path.mnt); exit2: - if (retry_estale(error, lookup_flags)) - should_retry = true; path_put(&new_path); exit1: path_put(&old_path); - if (should_retry) { - should_retry = false; +put_names: + if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } -put_names: putname(from); putname(to); return error; -- 2.30.2
