user/sven/linux.git/include/linux/lockd, branch v5.18.13

nfs: block notification on fs with its own ->lock

2022-01-08T19:42:01Z

NFSv4.1 supports an optional lock notification feature which notifies the client when a lock comes available. (Normally NFSv4 clients just poll for locks if necessary.) To make that work, we need to request a blocking lock from the filesystem. We turned that off for NFS in commit f657f8eef3ff ("nfs: don't atempt blocking locks on nfs reexports") [sic] because it actually blocks the nfsd thread while waiting for the lock. Thanks to Vasily Averin for pointing out that NFS isn't the only filesystem with that problem. Any filesystem that leaves ->lock NULL will use posix_lock_file(), which does the right thing. Simplest is just to assume that any filesystem that defines its own ->lock is not safe to request a blocking lock from. So, this patch mostly reverts commit f657f8eef3ff ("nfs: don't atempt blocking locks on nfs reexports") [sic] and commit b840be2f00c0 ("lockd: don't attempt blocking locks on nfs reexports"), and instead uses a check of ->lock (Vasily's suggestion) to decide whether to support blocking lock notifications on a given filesystem. Also add a little documentation. Perhaps someday we could add back an export flag later to allow filesystems with "good" ->lock methods to support blocking lock notifications. Reported-by: Vasily Averin Signed-off-by: J. Bruce Fields [ cel: Description rewritten to address checkpatch nits ] [ cel: Fixed warning when SUNRPC debugging is disabled ] [ cel: Fixed NULL check ] Signed-off-by: Chuck Lever Reviewed-by: Vasily Averin

SUNRPC: Change return value type of .pc_encode

2021-10-13T15:34:49Z

Returning an undecorated integer is an age-old trope, but it's not clear (even to previous experts in this code) that the only valid return values are 1 and 0. These functions do not return a negative errno, rpc_stat value, or a positive length. Document there are only two valid return values by having .pc_encode return only true or false. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields

SUNRPC: Replace the "__be32 *p" parameter to .pc_encode

2021-10-13T15:34:49Z

The passed-in value of the "__be32 *p" parameter is now unused in every server-side XDR encoder, and can be removed. Note also that there is a line in each encoder that sets up a local pointer to a struct xdr_stream. Passing that pointer from the dispatcher instead saves one line per encoder function. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields

SUNRPC: Change return value type of .pc_decode

2021-10-13T14:29:41Z

Returning an undecorated integer is an age-old trope, but it's not clear (even to previous experts in this code) that the only valid return values are 1 and 0. These functions do not return a negative errno, rpc_stat value, or a positive length. Document there are only two valid return values by having .pc_decode return only true or false. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields

SUNRPC: Replace the "__be32 *p" parameter to .pc_decode

2021-10-13T14:29:41Z

The passed-in value of the "__be32 *p" parameter is now unused in every server-side XDR decoder, and can be removed. Note also that there is a line in each decoder that sets up a local pointer to a struct xdr_stream. Passing that pointer from the dispatcher instead saves one line per decoder function. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields

Keep read and write fds with each nlm_file

2021-08-23T22:05:31Z

We shouldn't really be using a read-only file descriptor to take a write lock. Most filesystems will put up with it. But NFS, for example, won't. Signed-off-by: J. Bruce Fields Signed-off-by: Chuck Lever

nlm: minor nlm_lookup_file argument change

2021-08-23T16:56:03Z

It'll come in handy to get the whole nlm_lock. Signed-off-by: J. Bruce Fields Signed-off-by: Chuck Lever

lockd: Remove stale comments

2021-07-07T00:14:42Z

Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields

lockd: remove KERNEL ifdefs

2019-11-12T16:43:29Z

Remove the __KERNEL__ ifdefs from the non-UAPI sunrpc headers, as those can't be included from user space programs. Signed-off-by: Christoph Hellwig Signed-off-by: J. Bruce Fields

lockd: Convert NLM service fl_owner to nlm_lockowner

2019-07-03T21:52:08Z

Do as the NLM client: allocate and track a struct nlm_lockowner for use as the fl_owner for locks created by the NLM sever. This allows us to keep the svid within this structure for matching locks, and will allow us to track the pid of lockd in a future patch. It should also allow easier reference of the nlm_host in conflicting locks, and simplify lock hashing and comparison. Signed-off-by: Benjamin Coddington [bfields@redhat.com: fix type of some error returns] Signed-off-by: J. Bruce Fields