linux.git/include/linux/sunrpc/cache.h, branch v7.2-rc1

sunrpc: add a generic netlink family for cache upcalls

2026-06-01T15:08:18+00:00

The auth.unix.ip and auth.unix.gid caches live in the sunrpc module,
so they cannot use the nfsd generic netlink family. Create a new
"sunrpc" generic netlink family with its own "exportd" multicast
group to support cache upcall notifications for sunrpc-resident
caches.

Define a YAML spec (sunrpc_cache.yaml) with a cache-type enum
(ip_map, unix_gid), a cache-notify multicast event, and the
corresponding uapi header.

Implement sunrpc_cache_notify() in cache.c, which checks for
listeners on the exportd multicast group, builds and sends a
SUNRPC_CMD_CACHE_NOTIFY message with the cache-type attribute.

Register/unregister the sunrpc_nl_family in init_sunrpc() and
cleanup_sunrpc().

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

sunrpc: add helpers to count and snapshot pending cache requests

2026-06-01T15:08:18+00:00

Add sunrpc_cache_requests_count() and sunrpc_cache_requests_snapshot()
to allow callers to count and snapshot the pending upcall request list
without exposing struct cache_request outside of cache.c.

Both functions skip entries that no longer have CACHE_PENDING set.

The snapshot function takes a cache_get() reference on each item so the
caller can safely use them after the queue_lock is released.

These will be used by the nfsd generic netlink dumpit handler for
svc_export upcall requests.

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

sunrpc: add a cache_notify callback

2026-06-01T15:08:18+00:00

A later patch will be changing the kernel to send a netlink notification
when there is a pending cache_request. Add a new cache_notify operation
to struct cache_detail for this purpose.

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

sunrpc: rename sunrpc_cache_pipe_upcall_timeout()

2026-06-01T15:08:18+00:00

This function doesn't have anything to do with a timeout. The only
difference is that it warns if there are no listeners. Rename it to
sunrpc_cache_upcall_warn().

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

sunrpc: rename sunrpc_cache_pipe_upcall() to sunrpc_cache_upcall()

2026-06-01T15:08:18+00:00

Since it will soon also send an upcall via netlink, if configured.

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

sunrpc: split cache_detail queue into request and reader lists

2026-03-30T01:25:09+00:00

Replace the single interleaved queue (which mixed cache_request and
cache_reader entries distinguished by a ->reader flag) with two
dedicated lists: cd->requests for upcall requests and cd->readers
for open file handles.

Readers now track their position via a monotonically increasing
sequence number (next_seqno) rather than by their position in the
shared list. Each cache_request is assigned a seqno when enqueued,
and a new cache_next_request() helper finds the next request at or
after a given seqno.

This eliminates the cache_queue wrapper struct entirely, simplifies
the reader-skipping loops in cache_read/cache_poll/cache_ioctl/
cache_release, and makes the data flow easier to reason about.

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

sunrpc: convert queue_wait from global to per-cache-detail waitqueue

2026-03-30T01:25:09+00:00

The queue_wait waitqueue is currently a file-scoped global, so a
wake_up for one cache_detail wakes pollers on all caches. Convert it
to a per-cache-detail field so that only pollers on the relevant cache
are woken.

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

sunrpc: convert queue_lock from global spinlock to per-cache-detail lock

2026-03-30T01:25:09+00:00

The global queue_lock serializes all upcall queue operations across
every cache_detail instance. Convert it to a per-cache-detail spinlock
so that different caches (e.g. auth.unix.ip vs nfsd.fh) no longer
contend with each other on queue operations.

Signed-off-by: Jeff Layton 
Signed-off-by: Chuck Lever

SUNRPC: introduce cache_check_rcu to help check in rcu context

2025-01-06T14:37:40+00:00

This is a prepare patch to add cache_check_rcu, will use it with follow
patch.

Suggested-by: NeilBrown 
Signed-off-by: Yang Erkun 
Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

SUNRPC: change cache_head.flags bits to enum

2023-08-29T21:45:22+00:00

When a sequence of numbers are needed for internal-use only, an enum is
typically best.  The sequence will inevitably need to be changed one
day, and having an enum means the developer doesn't need to think about
renumbering after insertion or deletion.  Such patches will be easier
to review.

Signed-off-by: NeilBrown 
Signed-off-by: Chuck Lever