[PATCH 5.18 0883/1095] 9p: Drop kref usage

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 18:42:31 EST


From: Kent Overstreet <kent.overstreet@xxxxxxxxx>

[ Upstream commit 6cda12864cb0f99810a5809e11e3ee5b102c9a47 ]

An upcoming patch is going to require passing the client through
p9_req_put() -> p9_req_free(), but that's awkward with the kref
indirection - so this patch switches to using refcount_t directly.

Link: https://lkml.kernel.org/r/20220704014243.153050-1-kent.overstreet@xxxxxxxxx
Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Cc: Eric Van Hensbergen <ericvh@xxxxxxxxx>
Cc: Latchesar Ionkov <lucho@xxxxxxxxxx>
Signed-off-by: Dominique Martinet <asmadeus@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/net/9p/client.h | 6 +++---
net/9p/client.c | 19 ++++++++-----------
2 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index ec1d1706f43c..c038c2d73dae 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -76,7 +76,7 @@ enum p9_req_status_t {
struct p9_req_t {
int status;
int t_err;
- struct kref refcount;
+ refcount_t refcount;
wait_queue_head_t wq;
struct p9_fcall tc;
struct p9_fcall rc;
@@ -227,12 +227,12 @@ struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag);

static inline void p9_req_get(struct p9_req_t *r)
{
- kref_get(&r->refcount);
+ refcount_inc(&r->refcount);
}

static inline int p9_req_try_get(struct p9_req_t *r)
{
- return kref_get_unless_zero(&r->refcount);
+ return refcount_inc_not_zero(&r->refcount);
}

int p9_req_put(struct p9_req_t *r);
diff --git a/net/9p/client.c b/net/9p/client.c
index 8bba0d9cf975..0ee48e8b7220 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -305,7 +305,7 @@ p9_tag_alloc(struct p9_client *c, int8_t type, unsigned int max_size)
* callback), so p9_client_cb eats the second ref there
* as the pointer is duplicated directly by virtqueue_add_sgs()
*/
- refcount_set(&req->refcount.refcount, 2);
+ refcount_set(&req->refcount, 2);

return req;

@@ -370,18 +370,15 @@ static int p9_tag_remove(struct p9_client *c, struct p9_req_t *r)
return p9_req_put(r);
}

-static void p9_req_free(struct kref *ref)
-{
- struct p9_req_t *r = container_of(ref, struct p9_req_t, refcount);
-
- p9_fcall_fini(&r->tc);
- p9_fcall_fini(&r->rc);
- kmem_cache_free(p9_req_cache, r);
-}
-
int p9_req_put(struct p9_req_t *r)
{
- return kref_put(&r->refcount, p9_req_free);
+ if (refcount_dec_and_test(&r->refcount)) {
+ p9_fcall_fini(&r->tc);
+ p9_fcall_fini(&r->rc);
+ kmem_cache_free(p9_req_cache, r);
+ return 1;
+ }
+ return 0;
}
EXPORT_SYMBOL(p9_req_put);

--
2.35.1