Return-Path: Received: from mx2.netapp.com ([216.240.18.37]:58313 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932481Ab0IGUD4 (ORCPT ); Tue, 7 Sep 2010 16:03:56 -0400 Received: from [10.58.61.36] (panchal1-lxp.hq.netapp.com [10.58.61.36] (may be forged)) by smtp1.corp.netapp.com (8.13.1/8.13.1/NTAP-1.6) with ESMTP id o87K3tmO027444 for ; Tue, 7 Sep 2010 13:03:55 -0700 (PDT) Message-ID: <4C869AAB.40004@netapp.com> Date: Tue, 07 Sep 2010 16:03:55 -0400 From: Bryan Schumaker To: "linux-nfs@vger.kernel.org" Subject: [PATCH 6/6] NFS: readdir with vmapped pages Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 NFS readdir with vmapped pages We can use vmapped pages to read more information from the network at once. This will reduce the number of calls needed to complete a readdir. Signed-off-by: Bryan Schumaker --- diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 4e7df2a..dde5a89 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -901,8 +901,8 @@ static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo * server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL); server->dtsize = nfs_block_size(fsinfo->dtpref, NULL); - if (server->dtsize > PAGE_CACHE_SIZE) - server->dtsize = PAGE_CACHE_SIZE; + if (server->dtsize > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES) + server->dtsize = PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES; if (server->dtsize > server->rsize) server->dtsize = server->rsize; diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 6971946..ece0526 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -278,7 +278,7 @@ exit: /* Fill a page with xdr information before transferring to the cache page */ static inline -int nfs_readdir_xdr_filler(struct page *xdr_page, nfs_readdir_descriptor_t *desc, +int nfs_readdir_xdr_filler(struct page **pages, nfs_readdir_descriptor_t *desc, struct nfs_entry *entry, struct file *file, struct inode *inode) { struct rpc_cred *cred = nfs_file_cred(file); @@ -288,7 +288,7 @@ int nfs_readdir_xdr_filler(struct page *xdr_page, nfs_readdir_descriptor_t *desc again: timestamp = jiffies; gencount = nfs_inc_attr_generation_counter(); - error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, xdr_page, + error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, pages, NFS_SERVER(inode)->dtsize, desc->plus); if (error < 0) { /* We requested READDIRPLUS, but the server doesn't grok it */ @@ -388,22 +388,53 @@ out: /* Perform conversion from xdr to cache array */ static inline void nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry, - struct page *xdr_page, struct page *page) + void *xdr_page, struct page *page) { - __be32 *ptr = kmap(xdr_page); + __be32 *ptr = xdr_page; while (xdr_decode(desc, entry, &ptr) == 0) { if (nfs_readdir_add_to_array(entry, page) == -1) break; if (desc->plus == 1) nfs_prime_dcache(desc->file->f_path.dentry, entry); } - kunmap(xdr_page); +} + +static inline +void nfs_readdir_free_large_page(void *ptr, struct page **pages) +{ + unsigned int i; + if (ptr) + vm_unmap_ram(ptr, NFS_MAX_READDIR_PAGES); + for (i = 0; i < NFS_MAX_READDIR_PAGES; i++) + put_page(pages[i]); +} + +/* + * nfs_readdir_large_page will allocate pages that must be freed with a call + * to nfs_readdir_free_large_page + */ +static inline +void *nfs_readdir_large_page(struct page **pages) +{ + void *ptr = NULL; + struct page *page = NULL; + int i; + for (i = 0; i < NFS_MAX_READDIR_PAGES; i++) { + page = alloc_page(GFP_KERNEL); + pages[i] = page; + } + + ptr = vm_map_ram(pages, NFS_MAX_READDIR_PAGES, 0, PAGE_KERNEL); + if (IS_ERR_OR_NULL(ptr)) + nfs_readdir_free_large_page(ptr, pages); + return ptr; } static int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, struct inode *inode) { - struct page *xdr_page; + struct page *pages[NFS_MAX_READDIR_PAGES]; + void *pages_ptr = NULL; struct nfs_entry entry; struct file *file = desc->file; struct nfs_cache_array *array; @@ -416,6 +447,7 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, entry.fattr = nfs_alloc_fattr(); if (entry.fh == NULL || entry.fattr == NULL) goto out; + printk(KERN_DEBUG "%d %s %s", __LINE__, __FILE__, __func__); array = nfs_readdir_get_array(page); memset(array, 0, sizeof(struct nfs_cache_array)); @@ -426,18 +458,18 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, goto out; } - xdr_page = alloc_page(GFP_KERNEL); - if (!xdr_page) + pages_ptr = nfs_readdir_large_page(pages); + if (!pages_ptr) goto out_put_page; do { - status = nfs_readdir_xdr_filler(xdr_page, desc, &entry, file, inode); + status = nfs_readdir_xdr_filler(pages, desc, &entry, file, inode); if (status < 0) break; - nfs_readdir_page_filler(desc, &entry, xdr_page, page); + nfs_readdir_page_filler(desc, &entry, pages_ptr, page); } while (array->eof_index < 0 && array->size < MAX_READDIR_ARRAY); out_put_page: - put_page(xdr_page); + nfs_readdir_free_large_page(pages_ptr, pages); out: nfs_free_fattr(entry.fattr); nfs_free_fhandle(entry.fh); diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index c961bc9..f64382c 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -63,6 +63,12 @@ struct nfs_clone_mount { #define NFS_UNSPEC_PORT (-1) /* + * Maximum number of pages that readdir can use for creating + * a vmapped array of pages. + */ +#define NFS_MAX_READDIR_PAGES 8 + +/* * In-kernel mount arguments */ struct nfs_parsed_mount_data { diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c index fabb4f2..033ed04 100644 --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -611,7 +611,7 @@ out: */ static int nfs3_proc_readdir(struct dentry *dentry, struct rpc_cred *cred, - u64 cookie, struct page *page, unsigned int count, int plus) + u64 cookie, struct page **pages, unsigned int count, int plus) { struct inode *dir = dentry->d_inode; __be32 *verf = NFS_COOKIEVERF(dir); @@ -621,7 +621,7 @@ nfs3_proc_readdir(struct dentry *dentry, struct rpc_cred *cred, .verf = {verf[0], verf[1]}, .plus = plus, .count = count, - .pages = &page + .pages = pages }; struct nfs3_readdirres res = { .verf = verf, diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 089da5b..479f422 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2896,12 +2896,12 @@ static int nfs4_proc_mkdir(struct inode *dir, struct dentry *dentry, } static int _nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred, - u64 cookie, struct page *page, unsigned int count, int plus) + u64 cookie, struct page **pages, unsigned int count, int plus) { struct inode *dir = dentry->d_inode; struct nfs4_readdir_arg args = { .fh = NFS_FH(dir), - .pages = &page, + .pages = pages, .pgbase = 0, .count = count, .bitmask = NFS_SERVER(dentry->d_inode)->attr_bitmask, @@ -2932,14 +2932,14 @@ static int _nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred, } static int nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred, - u64 cookie, struct page *page, unsigned int count, int plus) + u64 cookie, struct page **pages, unsigned int count, int plus) { struct nfs4_exception exception = { }; int err; do { err = nfs4_handle_exception(NFS_SERVER(dentry->d_inode), _nfs4_proc_readdir(dentry, cred, cookie, - page, count, plus), + pages, count, plus), &exception); } while (exception.retry); return err; diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 08ef912..f2e2f97 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -4225,7 +4225,7 @@ static int decode_readdir(struct xdr_stream *xdr, struct rpc_rqst *req, struct n pglen = recvd; xdr_read_pages(xdr, pglen); - BUG_ON(pglen + readdir->pgbase > PAGE_CACHE_SIZE); + BUG_ON(pglen + readdir->pgbase > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES); kaddr = p = kmap_atomic(page, KM_USER0); end = p + ((pglen + readdir->pgbase) >> 2); entry = p; diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index fc46192..7d8cafa 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -1044,7 +1044,7 @@ struct nfs_rpc_ops { int (*mkdir) (struct inode *, struct dentry *, struct iattr *); int (*rmdir) (struct inode *, struct qstr *); int (*readdir) (struct dentry *, struct rpc_cred *, - u64, struct page *, unsigned int, int); + u64, struct page **, unsigned int, int); int (*mknod) (struct inode *, struct dentry *, struct iattr *, dev_t); int (*statfs) (struct nfs_server *, struct nfs_fh *,