NFS: move pnfs layouts to nfs_server structure

Layouts should be tracked per nfs_server (aka superblock)
instead of per struct nfs_client, which may have multiple FSIDs associated
with it.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 48 insertions, 28 deletions

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index d4d1954e9bb9..74780f9f852c 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -111,6 +111,7 @@ int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation, const nf
 static u32 initiate_file_draining(struct nfs_client *clp,
                                   struct cb_layoutrecallargs *args)
 {
+        struct nfs_server *server;
         struct pnfs_layout_hdr *lo;
         struct inode *ino;
         bool found = false;
@@ -118,21 +119,28 @@ static u32 initiate_file_draining(struct nfs_client *clp,
         LIST_HEAD(free_me_list);
 
         spin_lock(&clp->cl_lock);
-        list_for_each_entry(lo, &clp->cl_layouts, plh_layouts) {
-                if (nfs_compare_fh(&args->cbl_fh,
-                                   &NFS_I(lo->plh_inode)->fh))
-                        continue;
-                ino = igrab(lo->plh_inode);
-                if (!ino)
-                        continue;
-                found = true;
-                /* Without this, layout can be freed as soon
-                 * as we release cl_lock.
-                 */
-                get_layout_hdr(lo);
-                break;
+        rcu_read_lock();
+        list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+                list_for_each_entry(lo, &server->layouts, plh_layouts) {
+                        if (nfs_compare_fh(&args->cbl_fh,
+                                           &NFS_I(lo->plh_inode)->fh))
+                                continue;
+                        ino = igrab(lo->plh_inode);
+                        if (!ino)
+                                continue;
+                        found = true;
+                        /* Without this, layout can be freed as soon
+                         * as we release cl_lock.
+                         */
+                        get_layout_hdr(lo);
+                        break;
+                }
+                if (found)
+                        break;
         }
+        rcu_read_unlock();
         spin_unlock(&clp->cl_lock);
+
         if (!found)
                 return NFS4ERR_NOMATCHING_LAYOUT;
 
@@ -154,6 +162,7 @@ static u32 initiate_file_draining(struct nfs_client *clp,
 static u32 initiate_bulk_draining(struct nfs_client *clp,
                                   struct cb_layoutrecallargs *args)
 {
+        struct nfs_server *server;
         struct pnfs_layout_hdr *lo;
         struct inode *ino;
         u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
@@ -167,18 +176,24 @@ static u32 initiate_bulk_draining(struct nfs_client *clp,
         };
 
         spin_lock(&clp->cl_lock);
-        list_for_each_entry(lo, &clp->cl_layouts, plh_layouts) {
+        rcu_read_lock();
+        list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
                 if ((args->cbl_recall_type == RETURN_FSID) &&
-                    memcmp(&NFS_SERVER(lo->plh_inode)->fsid,
-                           &args->cbl_fsid, sizeof(struct nfs_fsid)))
-                        continue;
-                if (!igrab(lo->plh_inode))
+                    memcmp(&server->fsid, &args->cbl_fsid,
+                           sizeof(struct nfs_fsid)))
                         continue;
-                get_layout_hdr(lo);
-                BUG_ON(!list_empty(&lo->plh_bulk_recall));
-                list_add(&lo->plh_bulk_recall, &recall_list);
+
+                list_for_each_entry(lo, &server->layouts, plh_layouts) {
+                        if (!igrab(lo->plh_inode))
+                                continue;
+                        get_layout_hdr(lo);
+                        BUG_ON(!list_empty(&lo->plh_bulk_recall));
+                        list_add(&lo->plh_bulk_recall, &recall_list);
+                }
         }
+        rcu_read_unlock();
         spin_unlock(&clp->cl_lock);
+
         list_for_each_entry_safe(lo, tmp,
                                  &recall_list, plh_bulk_recall) {
                 ino = lo->plh_inode;
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 006f8ff0a3c0..5452ada59461 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -188,9 +188,6 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
         cred = rpc_lookup_machine_cred();
         if (!IS_ERR(cred))
                 clp->cl_machine_cred = cred;
-#if defined(CONFIG_NFS_V4_1)
-        INIT_LIST_HEAD(&clp->cl_layouts);
-#endif
         nfs_fscache_get_client_cookie(clp);
 
         return clp;
@@ -1063,6 +1060,7 @@ static struct nfs_server *nfs_alloc_server(void)
         INIT_LIST_HEAD(&server->client_link);
         INIT_LIST_HEAD(&server->master_link);
         INIT_LIST_HEAD(&server->delegations);
+        INIT_LIST_HEAD(&server->layouts);
 
         atomic_set(&server->active, 0);
 
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 29c0ca7fc347..ff8200772377 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -448,11 +448,17 @@ pnfs_destroy_layout(struct nfs_inode *nfsi)
 void
 pnfs_destroy_all_layouts(struct nfs_client *clp)
 {
+        struct nfs_server *server;
         struct pnfs_layout_hdr *lo;
         LIST_HEAD(tmp_list);
 
         spin_lock(&clp->cl_lock);
-        list_splice_init(&clp->cl_layouts, &tmp_list);
+        rcu_read_lock();
+        list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+                if (!list_empty(&server->layouts))
+                        list_splice_init(&server->layouts, &tmp_list);
+        }
+        rcu_read_unlock();
         spin_unlock(&clp->cl_lock);
 
         while (!list_empty(&tmp_list)) {
@@ -920,7 +926,8 @@ pnfs_update_layout(struct inode *ino,
         };
         unsigned pg_offset;
         struct nfs_inode *nfsi = NFS_I(ino);
-        struct nfs_client *clp = NFS_SERVER(ino)->nfs_client;
+        struct nfs_server *server = NFS_SERVER(ino);
+        struct nfs_client *clp = server->nfs_client;
         struct pnfs_layout_hdr *lo;
         struct pnfs_layout_segment *lseg = NULL;
         bool first = false;
@@ -964,7 +971,7 @@ pnfs_update_layout(struct inode *ino,
                  */
                 spin_lock(&clp->cl_lock);
                 BUG_ON(!list_empty(&lo->plh_layouts));
-                list_add_tail(&lo->plh_layouts, &clp->cl_layouts);
+                list_add_tail(&lo->plh_layouts, &server->layouts);
                 spin_unlock(&clp->cl_lock);
         }
 
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index f23b18831559..4faeac8f448a 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -78,7 +78,6 @@ struct nfs_client {
         /* The flags used for obtaining the clientid during EXCHANGE_ID */
         u32                     cl_exchange_flags;
         struct nfs4_session     *cl_session;    /* sharred session */
-        struct list_head        cl_layouts;
 #endif /* CONFIG_NFS_V4 */
 
 #ifdef CONFIG_NFS_FSCACHE
@@ -152,6 +151,7 @@ struct nfs_server {
         struct rb_root          openowner_id;
         struct rb_root          lockowner_id;
 #endif
+        struct list_head        layouts;
         struct list_head        delegations;
         void (*destroy)(struct nfs_server *);