From 56e4ebf877b6043c289bda32a5a7385b80c17dee Mon Sep 17 00:00:00 2001 From: Bryan Schumaker Date: Wed, 20 Oct 2010 15:44:37 -0400 Subject: [PATCH] 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 [trondmy: Added #include for linux/vmalloc.h> in fs/nfs/dir.c] Signed-off-by: Trond Myklebust --- fs/nfs/client.c | 4 +-- fs/nfs/dir.c | 66 +++++++++++++++++++++++++++++++++-------- fs/nfs/internal.h | 6 ++++ fs/nfs/nfs3proc.c | 4 +-- fs/nfs/nfs4proc.c | 8 ++--- fs/nfs/proc.c | 4 +-- include/linux/nfs_xdr.h | 2 +- 7 files changed, 71 insertions(+), 23 deletions(-) diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 5f01f42b3991..876ba8592706 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -903,8 +903,8 @@ 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 88cbcda76856..5d7da3ad4e85 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -33,6 +33,7 @@ #include #include #include +#include #include "delegation.h" #include "iostat.h" @@ -327,7 +328,7 @@ out: /* Fill a page with xdr information before transferring to the cache page */ static -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); @@ -337,7 +338,7 @@ 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 */ @@ -436,11 +437,11 @@ out: /* Perform conversion from xdr to cache array */ static void nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry, - struct page *xdr_page, struct page *page, unsigned int buflen) + void *xdr_page, struct page *page, unsigned int buflen) { struct xdr_stream stream; struct xdr_buf buf; - __be32 *ptr = kmap(xdr_page); + __be32 *ptr = xdr_page; buf.head->iov_base = xdr_page; buf.head->iov_len = buflen; @@ -458,18 +459,59 @@ void nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *e if (desc->plus == 1) nfs_prime_dcache(desc->file->f_path.dentry, entry); } - kunmap(xdr_page); +} + +static +void nfs_readdir_free_pagearray(struct page **pages, unsigned int npages) +{ + unsigned int i; + for (i = 0; i < npages; i++) + put_page(pages[i]); +} + +static +void nfs_readdir_free_large_page(void *ptr, struct page **pages, + unsigned int npages) +{ + vm_unmap_ram(ptr, npages); + nfs_readdir_free_pagearray(pages, npages); +} + +/* + * nfs_readdir_large_page will allocate pages that must be freed with a call + * to nfs_readdir_free_large_page + */ +static +void *nfs_readdir_large_page(struct page **pages, unsigned int npages) +{ + void *ptr; + unsigned int i; + + for (i = 0; i < npages; i++) { + struct page *page = alloc_page(GFP_KERNEL); + if (page == NULL) + goto out_freepages; + pages[i] = page; + } + + ptr = vm_map_ram(pages, NFS_MAX_READDIR_PAGES, 0, PAGE_KERNEL); + if (!IS_ERR_OR_NULL(ptr)) + return ptr; +out_freepages: + nfs_readdir_free_pagearray(pages, i); + return NULL; } 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; int status = 0; - unsigned int array_size = 1; + unsigned int array_size = ARRAY_SIZE(pages); entry.prev_cookie = 0; entry.cookie = *desc->dir_cookie; @@ -483,18 +525,18 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, memset(array, 0, sizeof(struct nfs_cache_array)); array->eof_index = -1; - xdr_page = alloc_page(GFP_KERNEL); - if (!xdr_page) + pages_ptr = nfs_readdir_large_page(pages, array_size); + if (!pages_ptr) goto out_release_array; 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, array_size * PAGE_SIZE); + nfs_readdir_page_filler(desc, &entry, pages_ptr, page, array_size * PAGE_SIZE); } while (array->eof_index < 0 && array->size < MAX_READDIR_ARRAY); - put_page(xdr_page); + nfs_readdir_free_large_page(pages_ptr, pages, array_size); out_release_array: nfs_readdir_release_array(page); out: diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 74b015598a43..7b0e894d00c8 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -62,6 +62,12 @@ 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 */ diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c index f8446b38dcb4..ce939c062a52 100644 --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -630,7 +630,7 @@ 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); @@ -640,7 +640,7 @@ 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 aa771c1af115..cb33c73206e3 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2823,12 +2823,12 @@ 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, @@ -2859,14 +2859,14 @@ 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/proc.c b/fs/nfs/proc.c index e5e84aa2af17..58e7f84fc1fd 100644 --- a/fs/nfs/proc.c +++ b/fs/nfs/proc.c @@ -534,14 +534,14 @@ nfs_proc_rmdir(struct inode *dir, struct qstr *name) */ static int nfs_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 nfs_readdirargs arg = { .fh = NFS_FH(dir), .cookie = cookie, .count = count, - .pages = &page, + .pages = pages, }; struct rpc_message msg = { .rpc_proc = &nfs_procedures[NFSPROC_READDIR], diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index ca0e8fd7feec..1b9a17a1f235 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -1026,7 +1026,7 @@ 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 *, -- 2.39.2