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>

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 4f802b0..b96736d 100644 (file)
--- 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;
                }
        }