pNFS: Ensure we check layout segment validity in the pg_init() callback
If we have a layout segment cached in pgio->pg_lseg, we should check it
for validity before reusing it in a new RPC request. Otherwise, if we
recoalesce, we can end up looping forever.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 3917a62..634adb3 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2073,10 +2073,22 @@ void pnfs_error_mark_layout_for_return(struct inode *inode,
EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
void
+pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio)
+{
+ if (pgio->pg_lseg == NULL ||
+ test_bit(NFS_LSEG_VALID, &pgio->pg_lseg->pls_flags))
+ return;
+ pnfs_put_lseg(pgio->pg_lseg);
+ pgio->pg_lseg = NULL;
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
+
+void
pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
u64 rd_size = req->wb_bytes;
+ pnfs_generic_pg_check_layout(pgio);
if (pgio->pg_lseg == NULL) {
if (pgio->pg_dreq == NULL)
rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
@@ -2107,6 +2119,7 @@ void
pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
struct nfs_page *req, u64 wb_size)
{
+ pnfs_generic_pg_check_layout(pgio);
if (pgio->pg_lseg == NULL) {
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,