NFSv4.1 pnfs_layoutcommit_inode fixes

Test NFS_INO_LAYOUTCOMMIT before kzalloc
Mark inode dirty to retry LAYOUTCOMMIT on kzalloc failure.
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Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 2a08ca0..ac71125 100644 (file)
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -982,6 +982,14 @@ pnfs_set_layoutcommit(struct nfs_write_data *wdata)
 }
 EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
 
+/*
+ * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
+ * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
+ * data to disk to allow the server to recover the data if it crashes.
+ * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
+ * is off, and a COMMIT is sent to a data server, or
+ * if WRITEs to a data server return NFS_DATA_SYNC.
+ */
 int
 pnfs_layoutcommit_inode(struct inode *inode, int sync)
 {
@@ -994,10 +1002,18 @@ pnfs_layoutcommit_inode(struct inode *inode, int sync)
 
        dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
 
+       if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
+               return 0;
+
        /* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
        data = kzalloc(sizeof(*data), GFP_NOFS);
-       spin_lock(&inode->i_lock);
+       if (!data) {
+               mark_inode_dirty_sync(inode);
+               status = -ENOMEM;
+               goto out;
+       }
 
+       spin_lock(&inode->i_lock);
        if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
                spin_unlock(&inode->i_lock);
                kfree(data);
@@ -1014,16 +1030,8 @@ pnfs_layoutcommit_inode(struct inode *inode, int sync)
        lseg->pls_end_pos = 0;
        lseg->pls_lc_cred = NULL;
 
-       if (!data) {
-               put_lseg(lseg);
-               spin_unlock(&inode->i_lock);
-               put_rpccred(cred);
-               status = -ENOMEM;
-               goto out;
-       } else {
-               memcpy(&data->args.stateid.data, nfsi->layout->plh_stateid.data,
-                       sizeof(nfsi->layout->plh_stateid.data));
-       }
+       memcpy(&data->args.stateid.data, nfsi->layout->plh_stateid.data,
+               sizeof(nfsi->layout->plh_stateid.data));
        spin_unlock(&inode->i_lock);
 
        data->args.inode = inode;