Merge tag 'sunxi-fixes-for-4.3' of https://git.kernel.org/pub/scm/linux/kernel/git...

[linux-drm-fsl-dcu.git] / fs / nfs / pnfs.c

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index ba1246433794f0b917ac84738b2d952fd782b2fd..8abe27165ad044a22ce4079cc410d9052a1c3378 100644 (file)
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1104,20 +1104,15 @@ bool pnfs_roc(struct inode *ino)
                        mark_lseg_invalid(lseg, &tmp_list);
                        found = true;
                }
-       /* pnfs_prepare_layoutreturn() grabs lo ref and it will be put
-        * in pnfs_roc_release(). We don't really send a layoutreturn but
-        * still want others to view us like we are sending one!
-        *
-        * If pnfs_prepare_layoutreturn() fails, it means someone else is doing
-        * LAYOUTRETURN, so we proceed like there are no layouts to return.
-        *
-        * ROC in three conditions:
+       /* ROC in two conditions:
         * 1. there are ROC lsegs
         * 2. we don't send layoutreturn
-        * 3. no others are sending layoutreturn
         */
-       if (found && !layoutreturn && pnfs_prepare_layoutreturn(lo))
+       if (found && !layoutreturn) {
+               /* lo ref dropped in pnfs_roc_release() */
+               pnfs_get_layout_hdr(lo);
                roc = true;
+       }
 
 out_noroc:
        spin_unlock(&ino->i_lock);
@@ -1172,6 +1167,26 @@ void pnfs_roc_get_barrier(struct inode *ino, u32 *barrier)
        spin_unlock(&ino->i_lock);
 }
 
+bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
+{
+       struct nfs_inode *nfsi = NFS_I(ino);
+        struct pnfs_layout_hdr *lo;
+        bool sleep = false;
+
+       /* we might not have grabbed lo reference. so need to check under
+        * i_lock */
+        spin_lock(&ino->i_lock);
+        lo = nfsi->layout;
+        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
+                sleep = true;
+        spin_unlock(&ino->i_lock);
+
+        if (sleep)
+                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
+
+        return sleep;
+}
+
 /*
  * Compare two layout segments for sorting into layout cache.
  * We want to preferentially return RW over RO layouts, so ensure those