pnfs: allow splicing pre-encoded pages into the layoutcommit args
Currently there is no XDR buffer space allocated for the per-layout driver
layoutcommit payload, which leads to server buffer overflows in the
blocklayout driver even under simple workloads. As we can't do per-layout
sizes for XDR operations we'll have to splice a previously encoded list
of pages into the XDR stream, similar to how we handle ACL buffers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 57b5728..8827ab1 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1854,6 +1854,7 @@
int
pnfs_layoutcommit_inode(struct inode *inode, bool sync)
{
+ struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
struct nfs4_layoutcommit_data *data;
struct nfs_inode *nfsi = NFS_I(inode);
loff_t end_pos;
@@ -1904,6 +1905,20 @@
data->args.lastbytewritten = end_pos - 1;
data->res.server = NFS_SERVER(inode);
+ if (ld->prepare_layoutcommit) {
+ status = ld->prepare_layoutcommit(&data->args);
+ if (status) {
+ spin_lock(&inode->i_lock);
+ 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;
+ }
+ }
+
+
status = nfs4_proc_layoutcommit(data, sync);
out:
if (status)