From faca536008375bece23783e7382b5d0356c13ba5 Mon Sep 17 00:00:00 2001 From: Karsten Graul Date: Wed, 29 Apr 2020 17:10:48 +0200 Subject: [PATCH] net/smc: use mutex instead of rwlock_t to protect buffers The locks for sndbufs and rmbs are never used from atomic context. Using a mutex for these locks will allow to nest locks with other mutexes. Signed-off-by: Karsten Graul Reviewed-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/smc_core.c | 22 +++++++++++----------- net/smc/smc_core.h | 4 ++-- 2 files changed, 13 insertions(+), 13 deletions(-) diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index a1463da14614..8a43d2948493 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -385,8 +385,8 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) lgr->freefast = 0; lgr->freeing = 0; lgr->vlan_id = ini->vlan_id; - rwlock_init(&lgr->sndbufs_lock); - rwlock_init(&lgr->rmbs_lock); + mutex_init(&lgr->sndbufs_lock); + mutex_init(&lgr->rmbs_lock); rwlock_init(&lgr->conns_lock); for (i = 0; i < SMC_RMBE_SIZES; i++) { INIT_LIST_HEAD(&lgr->sndbufs[i]); @@ -456,9 +456,9 @@ static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc, } if (rmb_desc->is_reg_err) { /* buf registration failed, reuse not possible */ - write_lock_bh(&lgr->rmbs_lock); + mutex_lock(&lgr->rmbs_lock); list_del(&rmb_desc->list); - write_unlock_bh(&lgr->rmbs_lock); + mutex_unlock(&lgr->rmbs_lock); smc_buf_free(lgr, true, rmb_desc); } else { @@ -1059,19 +1059,19 @@ int smc_uncompress_bufsize(u8 compressed) * buffer size; if not available, return NULL */ static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize, - rwlock_t *lock, + struct mutex *lock, struct list_head *buf_list) { struct smc_buf_desc *buf_slot; - read_lock_bh(lock); + mutex_lock(lock); list_for_each_entry(buf_slot, buf_list, list) { if (cmpxchg(&buf_slot->used, 0, 1) == 0) { - read_unlock_bh(lock); + mutex_unlock(lock); return buf_slot; } } - read_unlock_bh(lock); + mutex_unlock(lock); return NULL; } @@ -1220,8 +1220,8 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) struct smc_link_group *lgr = conn->lgr; struct list_head *buf_list; int bufsize, bufsize_short; + struct mutex *lock; /* lock buffer list */ int sk_buf_size; - rwlock_t *lock; if (is_rmb) /* use socket recv buffer size (w/o overhead) as start value */ @@ -1262,9 +1262,9 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) continue; buf_desc->used = 1; - write_lock_bh(lock); + mutex_lock(lock); list_add(&buf_desc->list, buf_list); - write_unlock_bh(lock); + mutex_unlock(lock); break; /* found */ } diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index d785656b3489..379ced490c49 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -205,9 +205,9 @@ struct smc_link_group { unsigned short vlan_id; /* vlan id of link group */ struct list_head sndbufs[SMC_RMBE_SIZES];/* tx buffers */ - rwlock_t sndbufs_lock; /* protects tx buffers */ + struct mutex sndbufs_lock; /* protects tx buffers */ struct list_head rmbs[SMC_RMBE_SIZES]; /* rx buffers */ - rwlock_t rmbs_lock; /* protects rx buffers */ + struct mutex rmbs_lock; /* protects rx buffers */ u8 id[SMC_LGR_ID_SIZE]; /* unique lgr id */ struct delayed_work free_work; /* delayed freeing of an lgr */ -- 2.11.0