NFSv4.1/pNFS: pnfs_error_mark_layout_for_return() must always return layout

Fix a bug whereby if all the layout segments could be immediately freed,
the call to pnfs_error_mark_layout_for_return() would never result in
a layoutreturn.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 449c4782cab37da830ab303cf35ed5f0f542c2eb..8e1d4229bf2df5280df215f8e22567c2c9ed1d73 100644 (file)
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1768,17 +1768,18 @@ pnfs_set_plh_return_iomode(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode)
        lo->plh_return_iomode = iomode;
 }
 
-void
+int
 pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
                                struct list_head *tmp_list,
                                struct pnfs_layout_range *return_range)
 {
        struct pnfs_layout_segment *lseg, *next;
+       int remaining = 0;
 
        dprintk("%s:Begin lo %p\n", __func__, lo);
 
        if (list_empty(&lo->plh_segs))
-               return;
+               return 0;
 
        assert_spin_locked(&lo->plh_inode->i_lock);
 
@@ -1791,10 +1792,12 @@ pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
                                lseg->pls_range.length);
                        set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
                        pnfs_set_plh_return_iomode(lo, return_range->iomode);
-                       mark_lseg_invalid(lseg, tmp_list);
+                       if (!mark_lseg_invalid(lseg, tmp_list))
+                               remaining++;
                        set_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
                                        &lo->plh_flags);
                }
+       return remaining;
 }
 
 void pnfs_error_mark_layout_for_return(struct inode *inode,
@@ -1808,6 +1811,7 @@ void pnfs_error_mark_layout_for_return(struct inode *inode,
                .length = NFS4_MAX_UINT64,
        };
        LIST_HEAD(free_me);
+       bool return_now = false;
 
        spin_lock(&inode->i_lock);
        /* set failure bit so that pnfs path will be retried later */
@@ -1818,10 +1822,20 @@ void pnfs_error_mark_layout_for_return(struct inode *inode,
         * segments at hand when sending layoutreturn. See pnfs_put_lseg()
         * for how it works.
         */
-       pnfs_mark_matching_lsegs_return(lo, &free_me, &range);
-       spin_unlock(&inode->i_lock);
+       if (!pnfs_mark_matching_lsegs_return(lo, &free_me, &range)) {
+               nfs4_stateid stateid;
+               enum pnfs_iomode iomode = lo->plh_return_iomode;
+
+               nfs4_stateid_copy(&stateid, &lo->plh_stateid);
+               return_now = pnfs_prepare_layoutreturn(lo);
+               spin_unlock(&inode->i_lock);
+               if (return_now)
+                       pnfs_send_layoutreturn(lo, &stateid, iomode, false);
+       } else {
+               spin_unlock(&inode->i_lock);
+               nfs_commit_inode(inode, 0);
+       }
        pnfs_free_lseg_list(&free_me);
-       nfs_commit_inode(inode, 0);
 }
 EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
 

diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 4bd7faf9ce5072e36d75ac07cc6814e0c1374f2c..3d0f513a4a77f39c5a1bf91a8f8ecbae06695218 100644 (file)
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -266,7 +266,7 @@ int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
 int pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
                                struct list_head *tmp_list,
                                struct pnfs_layout_range *recall_range);
-void pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
+int pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
                                struct list_head *tmp_list,
                                struct pnfs_layout_range *recall_range);
 bool pnfs_roc(struct inode *ino);