From 40859d7ee64ed6bfad8a4e93f9bb5c1074afadff Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 30 Nov 2005 18:09:02 -0500 Subject: 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 Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 29 ++++++++++++++++++++++------- 1 file changed, 22 insertions(+), 7 deletions(-) (limited to 'fs/nfs/write.c') diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 80bc4ea1b82..1ce0c200df1 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -89,18 +89,33 @@ static mempool_t *nfs_commit_mempool; static DECLARE_WAIT_QUEUE_HEAD(nfs_write_congestion); -static inline struct nfs_write_data *nfs_commit_alloc(void) +static inline struct nfs_write_data *nfs_commit_alloc(unsigned int pagecount) { struct nfs_write_data *p = mempool_alloc(nfs_commit_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_commit_mempool); + p = NULL; + } + } } return p; } static inline void nfs_commit_free(struct nfs_write_data *p) { + if (p && (p->pagevec != &p->page_array[0])) + kfree(p->pagevec); mempool_free(p, nfs_commit_mempool); } @@ -167,7 +182,7 @@ static int nfs_writepage_sync(struct nfs_open_context *ctx, struct inode *inode, int result, written = 0; struct nfs_write_data *wdata; - wdata = nfs_writedata_alloc(); + wdata = nfs_writedata_alloc(1); if (!wdata) return -ENOMEM; @@ -909,7 +924,7 @@ static int nfs_flush_multi(struct list_head *head, struct inode *inode, int how) nbytes = req->wb_bytes; for (;;) { - data = nfs_writedata_alloc(); + data = nfs_writedata_alloc(1); if (!data) goto out_bad; list_add(&data->pages, &list); @@ -973,7 +988,7 @@ static int nfs_flush_one(struct list_head *head, struct inode *inode, int how) if (NFS_SERVER(inode)->wsize < PAGE_CACHE_SIZE) return nfs_flush_multi(head, inode, how); - data = nfs_writedata_alloc(); + data = nfs_writedata_alloc(NFS_SERVER(inode)->wpages); if (!data) goto out_bad; @@ -1241,12 +1256,12 @@ static void nfs_commit_rpcsetup(struct list_head *head, * Commit dirty pages */ static int -nfs_commit_list(struct list_head *head, int how) +nfs_commit_list(struct inode *inode, struct list_head *head, int how) { struct nfs_write_data *data; struct nfs_page *req; - data = nfs_commit_alloc(); + data = nfs_commit_alloc(NFS_SERVER(inode)->wpages); if (!data) goto out_bad; @@ -1351,7 +1366,7 @@ int nfs_commit_inode(struct inode *inode, int how) res = nfs_scan_commit(inode, &head, 0, 0); spin_unlock(&nfsi->req_lock); if (res) { - error = nfs_commit_list(&head, how); + error = nfs_commit_list(inode, &head, how); if (error < 0) return error; } -- cgit v1.2.3