NFSv4: Fix up locking for nfs4_state_owner

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 18 insertions, 5 deletions

diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 5c0dd26d0985..78a53f5a9f18 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -126,6 +126,7 @@ static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status
  * semantics by allowing the server to identify replayed requests.
  */
 struct nfs4_state_owner {
+        spinlock_t           so_lock;
         struct list_head     so_list;    /* per-clientid list of state_owners */
         struct nfs4_client   *so_client;
         u32                  so_id;      /* 32-bit identifier, unique */
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 2d9357cf3fc5..9c1da34036aa 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -212,6 +212,7 @@ static void update_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid,
 
         open_flags &= (FMODE_READ|FMODE_WRITE);
         /* Protect against nfs4_find_state() */
+        spin_lock(&state->owner->so_lock);
         spin_lock(&inode->i_lock);
         state->state |= open_flags;
         /* NB! List reordering - see the reclaim code for why.  */
@@ -221,6 +222,7 @@ static void update_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid,
                 state->nreaders++;
         memcpy(&state->stateid, stateid, sizeof(state->stateid));
         spin_unlock(&inode->i_lock);
+        spin_unlock(&state->owner->so_lock);
 }
 
 /*
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index c59ef90e956b..2d5a6a2b9dec 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -267,6 +267,7 @@ nfs4_alloc_state_owner(void)
         sp = kzalloc(sizeof(*sp),GFP_KERNEL);
         if (!sp)
                 return NULL;
+        spin_lock_init(&sp->so_lock);
         INIT_LIST_HEAD(&sp->so_states);
         INIT_LIST_HEAD(&sp->so_delegations);
         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
@@ -438,20 +439,23 @@ nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
         if (state)
                 goto out;
         new = nfs4_alloc_open_state();
+        spin_lock(&owner->so_lock);
         spin_lock(&inode->i_lock);
         state = __nfs4_find_state_byowner(inode, owner);
         if (state == NULL && new != NULL) {
                 state = new;
-                /* Note: The reclaim code dictates that we add stateless
-                 * and read-only stateids to the end of the list */
-                list_add_tail(&state->open_states, &owner->so_states);
                 state->owner = owner;
                 atomic_inc(&owner->so_count);
                 list_add(&state->inode_states, &nfsi->open_states);
                 state->inode = igrab(inode);
                 spin_unlock(&inode->i_lock);
+                /* Note: The reclaim code dictates that we add stateless
+                 * and read-only stateids to the end of the list */
+                list_add_tail(&state->open_states, &owner->so_states);
+                spin_unlock(&owner->so_lock);
         } else {
                 spin_unlock(&inode->i_lock);
+                spin_unlock(&owner->so_lock);
                 if (new)
                         nfs4_free_open_state(new);
         }
@@ -468,12 +472,14 @@ void nfs4_put_open_state(struct nfs4_state *state)
         struct inode *inode = state->inode;
         struct nfs4_state_owner *owner = state->owner;
 
-        if (!atomic_dec_and_lock(&state->count, &inode->i_lock))
+        if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
                 return;
+        spin_lock(&inode->i_lock);
         if (!list_empty(&state->inode_states))
                 list_del(&state->inode_states);
-        spin_unlock(&inode->i_lock);
         list_del(&state->open_states);
+        spin_unlock(&inode->i_lock);
+        spin_unlock(&owner->so_lock);
         iput(inode);
         BUG_ON (state->state != 0);
         nfs4_free_open_state(state);
@@ -491,6 +497,7 @@ void nfs4_close_state(struct nfs4_state *state, mode_t mode)
 
         atomic_inc(&owner->so_count);
         /* Protect against nfs4_find_state() */
+        spin_lock(&owner->so_lock);
         spin_lock(&inode->i_lock);
         if (mode & FMODE_READ)
                 state->nreaders--;
@@ -503,6 +510,7 @@ void nfs4_close_state(struct nfs4_state *state, mode_t mode)
                 list_move_tail(&state->open_states, &owner->so_states);
         }
         spin_unlock(&inode->i_lock);
+        spin_unlock(&owner->so_lock);
         newstate = 0;
         if (state->state != 0) {
                 if (state->nreaders)
@@ -899,6 +907,7 @@ static void nfs4_state_mark_reclaim(struct nfs4_client *clp)
         list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
                 sp->so_seqid.counter = 0;
                 sp->so_seqid.flags = 0;
+                spin_lock(&sp->so_lock);
                 list_for_each_entry(state, &sp->so_states, open_states) {
                         list_for_each_entry(lock, &state->lock_states, ls_locks) {
                                 lock->ls_seqid.counter = 0;
@@ -906,6 +915,7 @@ static void nfs4_state_mark_reclaim(struct nfs4_client *clp)
                                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
                         }
                 }
+                spin_unlock(&sp->so_lock);
         }
 }