1 files changed, 38 insertions, 18 deletions

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 54cea8ad5a76..0e6e63f55db4 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -108,42 +108,62 @@ int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation, const nf
 
 #if defined(CONFIG_NFS_V4_1)
 
-static u32 initiate_file_draining(struct nfs_client *clp,
-                                  struct cb_layoutrecallargs *args)
+/*
+ * Lookup a layout by filehandle.
+ *
+ * Note: gets a refcount on the layout hdr and on its respective inode.
+ * Caller must put the layout hdr and the inode.
+ *
+ * TODO: keep track of all layouts (and delegations) in a hash table
+ * hashed by filehandle.
+ */
+static struct pnfs_layout_hdr * get_layout_by_fh_locked(struct nfs_client *clp, struct nfs_fh *fh)
 {
         struct nfs_server *server;
-        struct pnfs_layout_hdr *lo;
         struct inode *ino;
-        bool found = false;
-        u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
-        LIST_HEAD(free_me_list);
+        struct pnfs_layout_hdr *lo;
 
-        spin_lock(&clp->cl_lock);
-        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))
+                        if (nfs_compare_fh(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;
+                        return lo;
                 }
-                if (found)
-                        break;
         }
+
+        return NULL;
+}
+
+static struct pnfs_layout_hdr * get_layout_by_fh(struct nfs_client *clp, struct nfs_fh *fh)
+{
+        struct pnfs_layout_hdr *lo;
+
+        spin_lock(&clp->cl_lock);
+        rcu_read_lock();
+        lo = get_layout_by_fh_locked(clp, fh);
         rcu_read_unlock();
         spin_unlock(&clp->cl_lock);
 
-        if (!found)
+        return lo;
+}
+
+static u32 initiate_file_draining(struct nfs_client *clp,
+                                  struct cb_layoutrecallargs *args)
+{
+        struct inode *ino;
+        struct pnfs_layout_hdr *lo;
+        u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
+        LIST_HEAD(free_me_list);
+
+        lo = get_layout_by_fh(clp, &args->cbl_fh);
+        if (!lo)
                 return NFS4ERR_NOMATCHING_LAYOUT;
 
+        ino = lo->plh_inode;
         spin_lock(&ino->i_lock);
         if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
             mark_matching_lsegs_invalid(lo, &free_me_list,