From 7cb58f19edd5e90940d1c80e467cdc6289706729 Mon Sep 17 00:00:00 2001 From: Andriy Skulysh Date: Wed, 26 Jul 2017 11:22:19 -0400 Subject: [PATCH] staging: lustre: ldlm: crash on umount in cleanup_resource cfs_hash_for_each_relax() assumes that cfs_hash_put_locked() doesn't release bd lock, but it isn't true for ldlm_res_hop_put_locked(). Add recfcount on next hnode in cfs_hash_for_each_relax() and remove ldlm_res_hop_put_locked() Signed-off-by: Andriy Skulysh Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6304 Xyratex-bug-id: MRP-2352 Reviewed-by: Vitaly Fertman Reviewed-by: Alexander Boyko Tested-by: Alexander Lezhoev Reviewed-on: http://review.whamcloud.com/13908 Reviewed-by: Oleg Drokin Signed-off-by: James Simmons Signed-off-by: Greg Kroah-Hartman --- drivers/staging/lustre/lnet/libcfs/hash.c | 47 ++++++++++++------- .../lustre/lustre/ldlm/ldlm_internal.h | 3 -- .../lustre/lustre/ldlm/ldlm_resource.c | 43 ----------------- 3 files changed, 31 insertions(+), 62 deletions(-) diff --git a/drivers/staging/lustre/lnet/libcfs/hash.c b/drivers/staging/lustre/lnet/libcfs/hash.c index 5c2ce2ee6fd9..ff54eaf6651b 100644 --- a/drivers/staging/lustre/lnet/libcfs/hash.c +++ b/drivers/staging/lustre/lnet/libcfs/hash.c @@ -1008,7 +1008,7 @@ cfs_hash_create(char *name, unsigned int cur_bits, unsigned int max_bits, LASSERT(ops->hs_object); LASSERT(ops->hs_keycmp); LASSERT(ops->hs_get); - LASSERT(ops->hs_put_locked); + LASSERT(ops->hs_put || ops->hs_put_locked); if (flags & CFS_HASH_REHASH) flags |= CFS_HASH_COUNTER; /* must have counter */ @@ -1553,19 +1553,20 @@ static int cfs_hash_for_each_relax(struct cfs_hash *hs, cfs_hash_for_each_cb_t func, void *data, int start) { + struct hlist_node *next = NULL; struct hlist_node *hnode; - struct hlist_node *tmp; struct cfs_hash_bd bd; u32 version; int count = 0; int stop_on_change; + int has_put_locked; int end = -1; int rc = 0; int i; stop_on_change = cfs_hash_with_rehash_key(hs) || - !cfs_hash_with_no_itemref(hs) || - !hs->hs_ops->hs_put_locked; + !cfs_hash_with_no_itemref(hs); + has_put_locked = hs->hs_ops->hs_put_locked != NULL; cfs_hash_lock(hs, 0); again: LASSERT(!cfs_hash_is_rehashing(hs)); @@ -1582,38 +1583,52 @@ again: version = cfs_hash_bd_version_get(&bd); cfs_hash_bd_for_each_hlist(hs, &bd, hhead) { - for (hnode = hhead->first; hnode;) { + hnode = hhead->first; + if (!hnode) + continue; + cfs_hash_get(hs, hnode); + + for (; hnode; hnode = next) { cfs_hash_bucket_validate(hs, &bd, hnode); - cfs_hash_get(hs, hnode); + next = hnode->next; + if (next) + cfs_hash_get(hs, next); cfs_hash_bd_unlock(hs, &bd, 0); cfs_hash_unlock(hs, 0); rc = func(hs, &bd, hnode, data); - if (stop_on_change) + if (stop_on_change || !has_put_locked) cfs_hash_put(hs, hnode); cond_resched(); count++; cfs_hash_lock(hs, 0); cfs_hash_bd_lock(hs, &bd, 0); - if (!stop_on_change) { - tmp = hnode->next; - cfs_hash_put_locked(hs, hnode); - hnode = tmp; - } else { /* bucket changed? */ + if (stop_on_change) { if (version != cfs_hash_bd_version_get(&bd)) - break; - /* safe to continue because no change */ - hnode = hnode->next; + rc = -EINTR; + } else if (has_put_locked) { + cfs_hash_put_locked(hs, hnode); } if (rc) /* callback wants to break iteration */ break; } - if (rc) /* callback wants to break iteration */ + if (next) { + if (has_put_locked) { + cfs_hash_put_locked(hs, next); + next = NULL; + } break; + } else if (rc) { + break; + } } cfs_hash_bd_unlock(hs, &bd, 0); + if (next && !has_put_locked) { + cfs_hash_put(hs, next); + next = NULL; + } if (rc) /* callback wants to break iteration */ break; } diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h b/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h index ec3b23cd09ec..2bf5c8491be9 100644 --- a/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h +++ b/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h @@ -106,9 +106,6 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns, extern unsigned int ldlm_enqueue_min; extern unsigned int ldlm_cancel_unused_locks_before_replay; -/* ldlm_resource.c */ -int ldlm_resource_putref_locked(struct ldlm_resource *res); - /* ldlm_lock.c */ struct ldlm_cb_set_arg { diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c index eab44dc898e1..4e805e775134 100644 --- a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c +++ b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c @@ -536,16 +536,6 @@ static void ldlm_res_hop_get_locked(struct cfs_hash *hs, ldlm_resource_getref(res); } -static void ldlm_res_hop_put_locked(struct cfs_hash *hs, - struct hlist_node *hnode) -{ - struct ldlm_resource *res; - - res = hlist_entry(hnode, struct ldlm_resource, lr_hash); - /* cfs_hash_for_each_nolock is the only chance we call it */ - ldlm_resource_putref_locked(res); -} - static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode) { struct ldlm_resource *res; @@ -561,7 +551,6 @@ static struct cfs_hash_ops ldlm_ns_hash_ops = { .hs_keycpy = NULL, .hs_object = ldlm_res_hop_object, .hs_get = ldlm_res_hop_get_locked, - .hs_put_locked = ldlm_res_hop_put_locked, .hs_put = ldlm_res_hop_put }; @@ -572,7 +561,6 @@ static struct cfs_hash_ops ldlm_ns_fid_hash_ops = { .hs_keycpy = NULL, .hs_object = ldlm_res_hop_object, .hs_get = ldlm_res_hop_get_locked, - .hs_put_locked = ldlm_res_hop_put_locked, .hs_put = ldlm_res_hop_put }; @@ -1249,37 +1237,6 @@ int ldlm_resource_putref(struct ldlm_resource *res) } EXPORT_SYMBOL(ldlm_resource_putref); -/* Returns 1 if the resource was freed, 0 if it remains. */ -int ldlm_resource_putref_locked(struct ldlm_resource *res) -{ - struct ldlm_namespace *ns = ldlm_res_to_ns(res); - - LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON); - CDEBUG(D_INFO, "putref res: %p count: %d\n", - res, atomic_read(&res->lr_refcount) - 1); - - if (atomic_dec_and_test(&res->lr_refcount)) { - struct cfs_hash_bd bd; - - cfs_hash_bd_get(ldlm_res_to_ns(res)->ns_rs_hash, - &res->lr_name, &bd); - __ldlm_resource_putref_final(&bd, res); - cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1); - /* NB: ns_rs_hash is created with CFS_HASH_NO_ITEMREF, - * so we should never be here while calling cfs_hash_del, - * cfs_hash_for_each_nolock is the only case we can get - * here, which is safe to release cfs_hash_bd_lock. - */ - if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free) - ns->ns_lvbo->lvbo_free(res); - kmem_cache_free(ldlm_resource_slab, res); - - cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1); - return 1; - } - return 0; -} - /** * Add a lock into a given resource into specified lock list. */ -- 2.20.1