NFSv4.1/pnfs: Fix setting of layoutcommit last write byte

If the NFS_INO_LAYOUTCOMMIT flag was unset, then we _must_ ensure that
we also reset the last write byte (lwb) for that layout. The current
code depends on us clearing the lwb when we clear NFS_INO_LAYOUTCOMMIT,
which is not the case when we call pnfs_clear_layoutcommit().

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

1 files changed, 8 insertions, 9 deletions

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 4f802b02fbb9..b96736df98e8 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2108,16 +2108,16 @@ pnfs_set_layoutcommit(struct nfs_pgio_header *hdr)
 
         spin_lock(&inode->i_lock);
         if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
+                nfsi->layout->plh_lwb = end_pos;
                 mark_as_dirty = true;
                 dprintk("%s: Set layoutcommit for inode %lu ",
                         __func__, inode->i_ino);
-        }
+        } else if (end_pos > nfsi->layout->plh_lwb)
+                nfsi->layout->plh_lwb = end_pos;
         if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &hdr->lseg->pls_flags)) {
                 /* references matched in nfs4_layoutcommit_release */
                 pnfs_get_lseg(hdr->lseg);
         }
-        if (end_pos > nfsi->layout->plh_lwb)
-                nfsi->layout->plh_lwb = end_pos;
         spin_unlock(&inode->i_lock);
         dprintk("%s: lseg %p end_pos %llu\n",
                 __func__, hdr->lseg, nfsi->layout->plh_lwb);
@@ -2137,16 +2137,16 @@ void pnfs_commit_set_layoutcommit(struct nfs_commit_data *data)
 
         spin_lock(&inode->i_lock);
         if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
+                nfsi->layout->plh_lwb = data->lwb;
                 mark_as_dirty = true;
                 dprintk("%s: Set layoutcommit for inode %lu ",
                         __func__, inode->i_ino);
-        }
+        } else if (data->lwb > nfsi->layout->plh_lwb)
+                nfsi->layout->plh_lwb = data->lwb;
         if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &data->lseg->pls_flags)) {
                 /* references matched in nfs4_layoutcommit_release */
                 pnfs_get_lseg(data->lseg);
         }
-        if (data->lwb > nfsi->layout->plh_lwb)
-                nfsi->layout->plh_lwb = data->lwb;
         spin_unlock(&inode->i_lock);
         dprintk("%s: lseg %p end_pos %llu\n",
                 __func__, data->lseg, nfsi->layout->plh_lwb);
@@ -2216,7 +2216,6 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
         pnfs_list_write_lseg(inode, &data->lseg_list);
 
         end_pos = nfsi->layout->plh_lwb;
-        nfsi->layout->plh_lwb = 0;
 
         nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
         spin_unlock(&inode->i_lock);
@@ -2233,11 +2232,11 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
                 status = ld->prepare_layoutcommit(&data->args);
                 if (status) {
                         spin_lock(&inode->i_lock);
-                        if (end_pos < nfsi->layout->plh_lwb)
+                        set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
+                        if (end_pos > nfsi->layout->plh_lwb)
                                 nfsi->layout->plh_lwb = end_pos;
                         spin_unlock(&inode->i_lock);
                         put_rpccred(data->cred);
-                        set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
                         goto clear_layoutcommitting;
                 }
         }