NFS: support large reads and writes on the wire
Most NFS server implementations allow up to 64KB reads and writes on the
wire. The Solaris NFS server allows up to a megabyte, for instance.
Now the Linux NFS client supports transfer sizes up to 1MB, too. This will
help reduce protocol and context switch overhead on read/write intensive NFS
workloads, and support larger atomic read and write operations on servers
that support them.
Test-plan:
Connectathon and iozone on mount point with wsize=rsize>32768 over TCP.
Tests with NFS over UDP to verify the maximum RPC payload size cap.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 4dff705..d38010b 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -38,9 +38,6 @@
# define NFS_DEBUG
#endif
-#define NFS_MAX_FILE_IO_BUFFER_SIZE 32768
-#define NFS_DEF_FILE_IO_BUFFER_SIZE 4096
-
/* Default timeout values */
#define NFS_MAX_UDP_TIMEOUT (60*HZ)
#define NFS_MAX_TCP_TIMEOUT (600*HZ)
@@ -462,18 +459,33 @@
*/
extern mempool_t *nfs_wdata_mempool;
-static inline struct nfs_write_data *nfs_writedata_alloc(void)
+static inline struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount)
{
struct nfs_write_data *p = mempool_alloc(nfs_wdata_mempool, SLAB_NOFS);
+
if (p) {
memset(p, 0, sizeof(*p));
INIT_LIST_HEAD(&p->pages);
+ if (pagecount < NFS_PAGEVEC_SIZE)
+ p->pagevec = &p->page_array[0];
+ else {
+ size_t size = ++pagecount * sizeof(struct page *);
+ p->pagevec = kmalloc(size, GFP_NOFS);
+ if (p->pagevec) {
+ memset(p->pagevec, 0, size);
+ } else {
+ mempool_free(p, nfs_wdata_mempool);
+ p = NULL;
+ }
+ }
}
return p;
}
static inline void nfs_writedata_free(struct nfs_write_data *p)
{
+ if (p && (p->pagevec != &p->page_array[0]))
+ kfree(p->pagevec);
mempool_free(p, nfs_wdata_mempool);
}
@@ -492,16 +504,33 @@
*/
extern mempool_t *nfs_rdata_mempool;
-static inline struct nfs_read_data *nfs_readdata_alloc(void)
+static inline struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount)
{
struct nfs_read_data *p = mempool_alloc(nfs_rdata_mempool, SLAB_NOFS);
- if (p)
+
+ if (p) {
memset(p, 0, sizeof(*p));
+ INIT_LIST_HEAD(&p->pages);
+ if (pagecount < NFS_PAGEVEC_SIZE)
+ p->pagevec = &p->page_array[0];
+ else {
+ size_t size = ++pagecount * sizeof(struct page *);
+ p->pagevec = kmalloc(size, GFP_NOFS);
+ if (p->pagevec) {
+ memset(p->pagevec, 0, size);
+ } else {
+ mempool_free(p, nfs_rdata_mempool);
+ p = NULL;
+ }
+ }
+ }
return p;
}
static inline void nfs_readdata_free(struct nfs_read_data *p)
{
+ if (p && (p->pagevec != &p->page_array[0]))
+ kfree(p->pagevec);
mempool_free(p, nfs_rdata_mempool);
}