NFS41: send real write size in layoutget
For buffer write, block layout client scan inode mapping to find
next hole and use offset-to-hole as layoutget length. Object
layout client uses offset-to-isize as layoutget length.
For direct write, both block layout and object layout use dreq->bytes_left.
Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index a34014a..f1027b0 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -37,6 +37,7 @@
#include <linux/bio.h> /* struct bio */
#include <linux/buffer_head.h> /* various write calls */
#include <linux/prefetch.h>
+#include <linux/pagevec.h>
#include "../pnfs.h"
#include "../internal.h"
@@ -1204,14 +1205,45 @@
return pnfs_generic_pg_test(pgio, prev, req);
}
+/*
+ * Return the number of contiguous bytes for a given inode
+ * starting at page frame idx.
+ */
+static u64 pnfs_num_cont_bytes(struct inode *inode, pgoff_t idx)
+{
+ struct address_space *mapping = inode->i_mapping;
+ pgoff_t end;
+
+ /* Optimize common case that writes from 0 to end of file */
+ end = DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE);
+ if (end != NFS_I(inode)->npages) {
+ rcu_read_lock();
+ end = radix_tree_next_hole(&mapping->page_tree, idx + 1, ULONG_MAX);
+ rcu_read_unlock();
+ }
+
+ if (!end)
+ return i_size_read(inode) - (idx << PAGE_CACHE_SHIFT);
+ else
+ return (end - idx) << PAGE_CACHE_SHIFT;
+}
+
static void
bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
if (pgio->pg_dreq != NULL &&
- !is_aligned_req(req, PAGE_CACHE_SIZE))
+ !is_aligned_req(req, PAGE_CACHE_SIZE)) {
nfs_pageio_reset_write_mds(pgio);
- else
- pnfs_generic_pg_init_write(pgio, req);
+ } else {
+ u64 wb_size;
+ if (pgio->pg_dreq == NULL)
+ wb_size = pnfs_num_cont_bytes(pgio->pg_inode,
+ req->wb_index);
+ else
+ wb_size = nfs_dreq_bytes_left(pgio->pg_dreq);
+
+ pnfs_generic_pg_init_write(pgio, req, wb_size);
+ }
}
static bool