When there is a single DS no striping constraints need to be placed on
the IO. When such constraint is applied then buffered reads don't
coalesce to the DS's rsize.
Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx>
---
fs/nfs/filelayout/filelayout.c | 2 ++
fs/nfs/filelayout/filelayout.h | 1 +
fs/nfs/filelayout/filelayoutdev.c | 4 +++-
3 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
index ad34a33b0737..cd819b795935 100644
--- a/fs/nfs/filelayout/filelayout.c
+++ b/fs/nfs/filelayout/filelayout.c
@@ -803,6 +803,8 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
size = pnfs_generic_pg_test(pgio, prev, req);
if (!size)
return 0;
+ else if (FILELAYOUT_LSEG(pgio->pg_lseg)->single_ds)
+ return size;
/* see if req and prev are in the same stripe */
if (prev) {
diff --git a/fs/nfs/filelayout/filelayout.h b/fs/nfs/filelayout/filelayout.h
index aed0748fd6ec..524920c2cbf8 100644
--- a/fs/nfs/filelayout/filelayout.h
+++ b/fs/nfs/filelayout/filelayout.h
@@ -65,6 +65,7 @@ struct nfs4_filelayout_segment {
struct nfs4_file_layout_dsaddr *dsaddr; /* Point to GETDEVINFO data */
unsigned int num_fh;
struct nfs_fh **fh_array;
+ bool single_ds;
};
struct nfs4_filelayout {
diff --git a/fs/nfs/filelayout/filelayoutdev.c b/fs/nfs/filelayout/filelayoutdev.c
index acf4b88889dc..95ebbe9e7ed4 100644
--- a/fs/nfs/filelayout/filelayoutdev.c
+++ b/fs/nfs/filelayout/filelayoutdev.c
@@ -243,8 +243,10 @@ nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
u32 i;
if (flseg->stripe_type == STRIPE_SPARSE) {
- if (flseg->num_fh == 1)
+ if (flseg->num_fh == 1) {
+ flseg->single_ds = true;
i = 0;
+ }
else if (flseg->num_fh == 0)
/* Use the MDS OPEN fh set in nfs_read_rpcsetup */
return NULL;
--
2.31.1
