Merge branch 'wip-2.6.34' into old-private-masterarchived-private-master

1 files changed, 105 insertions, 59 deletions

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 6dd48a4405b4..ea61d26e7871 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -10,6 +10,7 @@
 #include <linux/kthread.h>
 #include <linux/module.h>
 #include <linux/sched.h>
+#include <linux/slab.h>
 #include <linux/smp_lock.h>
 #include <linux/spinlock.h>
 
@@ -23,6 +24,8 @@
 
 static void nfs_do_free_delegation(struct nfs_delegation *delegation)
 {
+        if (delegation->cred)
+                put_rpccred(delegation->cred);
         kfree(delegation);
 }
 
@@ -35,13 +38,7 @@ static void nfs_free_delegation_callback(struct rcu_head *head)
 
 static void nfs_free_delegation(struct nfs_delegation *delegation)
 {
-        struct rpc_cred *cred;
-
-        cred = rcu_dereference(delegation->cred);
-        rcu_assign_pointer(delegation->cred, NULL);
         call_rcu(&delegation->rcu, nfs_free_delegation_callback);
-        if (cred)
-                put_rpccred(cred);
 }
 
 void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
@@ -92,7 +89,7 @@ out:
         return status;
 }
 
-static void nfs_delegation_claim_opens(struct inode *inode, const nfs4_stateid *stateid)
+static int nfs_delegation_claim_opens(struct inode *inode, const nfs4_stateid *stateid)
 {
         struct nfs_inode *nfsi = NFS_I(inode);
         struct nfs_open_context *ctx;
@@ -116,10 +113,11 @@ again:
                         err = nfs_delegation_claim_locks(ctx, state);
                 put_nfs_open_context(ctx);
                 if (err != 0)
-                        return;
+                        return err;
                 goto again;
         }
         spin_unlock(&inode->i_lock);
+        return 0;
 }
 
 /*
@@ -127,21 +125,35 @@ again:
  */
 void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
 {
-        struct nfs_delegation *delegation = NFS_I(inode)->delegation;
-        struct rpc_cred *oldcred;
+        struct nfs_delegation *delegation;
+        struct rpc_cred *oldcred = NULL;
 
-        if (delegation == NULL)
-                return;
-        memcpy(delegation->stateid.data, res->delegation.data,
-                        sizeof(delegation->stateid.data));
-        delegation->type = res->delegation_type;
-        delegation->maxsize = res->maxsize;
-        oldcred = delegation->cred;
-        delegation->cred = get_rpccred(cred);
-        clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
-        NFS_I(inode)->delegation_state = delegation->type;
-        smp_wmb();
-        put_rpccred(oldcred);
+        rcu_read_lock();
+        delegation = rcu_dereference(NFS_I(inode)->delegation);
+        if (delegation != NULL) {
+                spin_lock(&delegation->lock);
+                if (delegation->inode != NULL) {
+                        memcpy(delegation->stateid.data, res->delegation.data,
+                               sizeof(delegation->stateid.data));
+                        delegation->type = res->delegation_type;
+                        delegation->maxsize = res->maxsize;
+                        oldcred = delegation->cred;
+                        delegation->cred = get_rpccred(cred);
+                        clear_bit(NFS_DELEGATION_NEED_RECLAIM,
+                                  &delegation->flags);
+                        NFS_I(inode)->delegation_state = delegation->type;
+                        spin_unlock(&delegation->lock);
+                        put_rpccred(oldcred);
+                        rcu_read_unlock();
+                } else {
+                        /* We appear to have raced with a delegation return. */
+                        spin_unlock(&delegation->lock);
+                        rcu_read_unlock();
+                        nfs_inode_set_delegation(inode, cred, res);
+                }
+        } else {
+                rcu_read_unlock();
+        }
 }
 
 static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
@@ -164,9 +176,13 @@ static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation
         return inode;
 }
 
-static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfsi, const nfs4_stateid *stateid)
+static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfsi,
+                                                           const nfs4_stateid *stateid,
+                                                           struct nfs_client *clp)
 {
-        struct nfs_delegation *delegation = rcu_dereference(nfsi->delegation);
+        struct nfs_delegation *delegation =
+                rcu_dereference_protected(nfsi->delegation,
+                                          lockdep_is_held(&clp->cl_lock));
 
         if (delegation == NULL)
                 goto nomatch;
@@ -193,7 +209,7 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
 {
         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
         struct nfs_inode *nfsi = NFS_I(inode);
-        struct nfs_delegation *delegation;
+        struct nfs_delegation *delegation, *old_delegation;
         struct nfs_delegation *freeme = NULL;
         int status = 0;
 
@@ -211,10 +227,12 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
         spin_lock_init(&delegation->lock);
 
         spin_lock(&clp->cl_lock);
-        if (rcu_dereference(nfsi->delegation) != NULL) {
-                if (memcmp(&delegation->stateid, &nfsi->delegation->stateid,
-                                        sizeof(delegation->stateid)) == 0 &&
-                                delegation->type == nfsi->delegation->type) {
+        old_delegation = rcu_dereference_protected(nfsi->delegation,
+                                                   lockdep_is_held(&clp->cl_lock));
+        if (old_delegation != NULL) {
+                if (memcmp(&delegation->stateid, &old_delegation->stateid,
+                                        sizeof(old_delegation->stateid)) == 0 &&
+                                delegation->type == old_delegation->type) {
                         goto out;
                 }
                 /*
@@ -224,12 +242,12 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
                 dfprintk(FILE, "%s: server %s handed out "
                                 "a duplicate delegation!\n",
                                 __func__, clp->cl_hostname);
-                if (delegation->type <= nfsi->delegation->type) {
+                if (delegation->type <= old_delegation->type) {
                         freeme = delegation;
                         delegation = NULL;
                         goto out;
                 }
-                freeme = nfs_detach_delegation_locked(nfsi, NULL);
+                freeme = nfs_detach_delegation_locked(nfsi, NULL, clp);
         }
         list_add_rcu(&delegation->super_list, &clp->cl_delegations);
         nfsi->delegation_state = delegation->type;
@@ -261,30 +279,34 @@ static void nfs_msync_inode(struct inode *inode)
 /*
  * Basic procedure for returning a delegation to the server
  */
-static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation)
+static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
 {
         struct nfs_inode *nfsi = NFS_I(inode);
+        int err;
 
-        nfs_msync_inode(inode);
         /*
          * Guard against new delegated open/lock/unlock calls and against
          * state recovery
          */
         down_write(&nfsi->rwsem);
-        nfs_delegation_claim_opens(inode, &delegation->stateid);
+        err = nfs_delegation_claim_opens(inode, &delegation->stateid);
         up_write(&nfsi->rwsem);
-        nfs_msync_inode(inode);
+        if (err)
+                goto out;
 
-        return nfs_do_return_delegation(inode, delegation, 1);
+        err = nfs_do_return_delegation(inode, delegation, issync);
+out:
+        return err;
 }
 
 /*
  * Return all delegations that have been marked for return
  */
-void nfs_client_return_marked_delegations(struct nfs_client *clp)
+int nfs_client_return_marked_delegations(struct nfs_client *clp)
 {
         struct nfs_delegation *delegation;
         struct inode *inode;
+        int err = 0;
 
 restart:
         rcu_read_lock();
@@ -295,15 +317,21 @@ restart:
                 if (inode == NULL)
                         continue;
                 spin_lock(&clp->cl_lock);
-                delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL);
+                delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL, clp);
                 spin_unlock(&clp->cl_lock);
                 rcu_read_unlock();
-                if (delegation != NULL)
-                        __nfs_inode_return_delegation(inode, delegation);
+                if (delegation != NULL) {
+                        filemap_flush(inode->i_mapping);
+                        err = __nfs_inode_return_delegation(inode, delegation, 0);
+                }
                 iput(inode);
-                goto restart;
+                if (!err)
+                        goto restart;
+                set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
+                return err;
         }
         rcu_read_unlock();
+        return 0;
 }
 
 /*
@@ -318,9 +346,9 @@ void nfs_inode_return_delegation_noreclaim(struct inode *inode)
         struct nfs_inode *nfsi = NFS_I(inode);
         struct nfs_delegation *delegation;
 
-        if (rcu_dereference(nfsi->delegation) != NULL) {
+        if (rcu_access_pointer(nfsi->delegation) != NULL) {
                 spin_lock(&clp->cl_lock);
-                delegation = nfs_detach_delegation_locked(nfsi, NULL);
+                delegation = nfs_detach_delegation_locked(nfsi, NULL, clp);
                 spin_unlock(&clp->cl_lock);
                 if (delegation != NULL)
                         nfs_do_return_delegation(inode, delegation, 0);
@@ -334,12 +362,14 @@ int nfs_inode_return_delegation(struct inode *inode)
         struct nfs_delegation *delegation;
         int err = 0;
 
-        if (rcu_dereference(nfsi->delegation) != NULL) {
+        if (rcu_access_pointer(nfsi->delegation) != NULL) {
                 spin_lock(&clp->cl_lock);
-                delegation = nfs_detach_delegation_locked(nfsi, NULL);
+                delegation = nfs_detach_delegation_locked(nfsi, NULL, clp);
                 spin_unlock(&clp->cl_lock);
-                if (delegation != NULL)
-                        err = __nfs_inode_return_delegation(inode, delegation);
+                if (delegation != NULL) {
+                        nfs_msync_inode(inode);
+                        err = __nfs_inode_return_delegation(inode, delegation, 1);
+                }
         }
         return err;
 }
@@ -368,33 +398,47 @@ void nfs_super_return_all_delegations(struct super_block *sb)
                 spin_unlock(&delegation->lock);
         }
         rcu_read_unlock();
-        nfs_client_return_marked_delegations(clp);
+        if (nfs_client_return_marked_delegations(clp) != 0)
+                nfs4_schedule_state_manager(clp);
 }
 
-static void nfs_client_mark_return_all_delegations(struct nfs_client *clp)
+static
+void nfs_client_mark_return_all_delegation_types(struct nfs_client *clp, fmode_t flags)
 {
         struct nfs_delegation *delegation;
 
         rcu_read_lock();
         list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
-                set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
-                set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
+                if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE))
+                        continue;
+                if (delegation->type & flags)
+                        nfs_mark_return_delegation(clp, delegation);
         }
         rcu_read_unlock();
 }
 
+static void nfs_client_mark_return_all_delegations(struct nfs_client *clp)
+{
+        nfs_client_mark_return_all_delegation_types(clp, FMODE_READ|FMODE_WRITE);
+}
+
 static void nfs_delegation_run_state_manager(struct nfs_client *clp)
 {
         if (test_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state))
                 nfs4_schedule_state_manager(clp);
 }
 
-void nfs_expire_all_delegations(struct nfs_client *clp)
+void nfs_expire_all_delegation_types(struct nfs_client *clp, fmode_t flags)
 {
-        nfs_client_mark_return_all_delegations(clp);
+        nfs_client_mark_return_all_delegation_types(clp, flags);
         nfs_delegation_run_state_manager(clp);
 }
 
+void nfs_expire_all_delegations(struct nfs_client *clp)
+{
+        nfs_expire_all_delegation_types(clp, FMODE_READ|FMODE_WRITE);
+}
+
 /*
  * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
  */
@@ -413,8 +457,7 @@ static void nfs_client_mark_return_unreferenced_delegations(struct nfs_client *c
         list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
                 if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
                         continue;
-                set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
-                set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
+                nfs_mark_return_delegation(clp, delegation);
         }
         rcu_read_unlock();
 }
@@ -428,18 +471,21 @@ void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
 /*
  * Asynchronous delegation recall!
  */
-int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid)
+int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid,
+                                      int (*validate_stateid)(struct nfs_delegation *delegation,
+                                                              const nfs4_stateid *stateid))
 {
         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
         struct nfs_delegation *delegation;
 
         rcu_read_lock();
         delegation = rcu_dereference(NFS_I(inode)->delegation);
-        if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
-                                sizeof(delegation->stateid.data)) != 0) {
+
+        if (!validate_stateid(delegation, stateid)) {
                 rcu_read_unlock();
                 return -ENOENT;
         }
+
         nfs_mark_return_delegation(clp, delegation);
         rcu_read_unlock();
         nfs_delegation_run_state_manager(clp);
@@ -496,7 +542,7 @@ restart:
                 if (inode == NULL)
                         continue;
                 spin_lock(&clp->cl_lock);
-                delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL);
+                delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL, clp);
                 spin_unlock(&clp->cl_lock);
                 rcu_read_unlock();
                 if (delegation != NULL)