Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/nfs/read.c |
| 3 | * |
| 4 | * Block I/O for NFS |
| 5 | * |
| 6 | * Partial copy of Linus' read cache modifications to fs/nfs/file.c |
| 7 | * modified for async RPC by okir@monad.swb.de |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | */ |
| 9 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/time.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/errno.h> |
| 13 | #include <linux/fcntl.h> |
| 14 | #include <linux/stat.h> |
| 15 | #include <linux/mm.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/pagemap.h> |
| 18 | #include <linux/sunrpc/clnt.h> |
| 19 | #include <linux/nfs_fs.h> |
| 20 | #include <linux/nfs_page.h> |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 21 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | |
| 23 | #include <asm/system.h> |
Fred Isaman | bae724e | 2011-03-01 01:34:15 +0000 | [diff] [blame] | 24 | #include "pnfs.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | |
Andy Adamson | f11c88a | 2009-04-01 09:22:25 -0400 | [diff] [blame] | 26 | #include "nfs4_fs.h" |
Trond Myklebust | 49a70f2 | 2006-12-05 00:35:38 -0500 | [diff] [blame] | 27 | #include "internal.h" |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 28 | #include "iostat.h" |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 29 | #include "fscache.h" |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 30 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE |
| 32 | |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 33 | static const struct nfs_pageio_ops nfs_pageio_read_ops; |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 34 | static const struct rpc_call_ops nfs_read_partial_ops; |
| 35 | static const struct rpc_call_ops nfs_read_full_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 37 | static struct kmem_cache *nfs_rdata_cachep; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | |
Trond Myklebust | 8d5658c | 2007-04-10 09:26:35 -0400 | [diff] [blame] | 39 | struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount) |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 40 | { |
Trond Myklebust | b6ee8cd | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 41 | struct nfs_read_data *p; |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 42 | |
Trond Myklebust | b6ee8cd | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 43 | p = kmem_cache_zalloc(nfs_rdata_cachep, GFP_KERNEL); |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 44 | if (p) { |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 45 | INIT_LIST_HEAD(&p->pages); |
Trond Myklebust | e9f7bee | 2006-09-08 09:48:54 -0700 | [diff] [blame] | 46 | p->npages = pagecount; |
Chuck Lever | 0d0b5cb | 2006-05-25 01:40:53 -0400 | [diff] [blame] | 47 | if (pagecount <= ARRAY_SIZE(p->page_array)) |
| 48 | p->pagevec = p->page_array; |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 49 | else { |
Trond Myklebust | 93870d7 | 2010-05-13 12:51:03 -0400 | [diff] [blame] | 50 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL); |
Chuck Lever | 0d0b5cb | 2006-05-25 01:40:53 -0400 | [diff] [blame] | 51 | if (!p->pagevec) { |
Trond Myklebust | b6ee8cd | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 52 | kmem_cache_free(nfs_rdata_cachep, p); |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 53 | p = NULL; |
| 54 | } |
| 55 | } |
| 56 | } |
| 57 | return p; |
| 58 | } |
| 59 | |
Trond Myklebust | 1ae88b2 | 2009-08-12 09:12:30 -0400 | [diff] [blame] | 60 | void nfs_readdata_free(struct nfs_read_data *p) |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 61 | { |
| 62 | if (p && (p->pagevec != &p->page_array[0])) |
| 63 | kfree(p->pagevec); |
Trond Myklebust | b6ee8cd | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 64 | kmem_cache_free(nfs_rdata_cachep, p); |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 65 | } |
| 66 | |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 67 | void nfs_readdata_release(struct nfs_read_data *rdata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | { |
Fred Isaman | bae724e | 2011-03-01 01:34:15 +0000 | [diff] [blame] | 69 | put_lseg(rdata->lseg); |
Trond Myklebust | 383ba71 | 2008-02-19 20:04:20 -0500 | [diff] [blame] | 70 | put_nfs_open_context(rdata->args.context); |
| 71 | nfs_readdata_free(rdata); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | } |
| 73 | |
| 74 | static |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | int nfs_return_empty_page(struct page *page) |
| 76 | { |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 77 | zero_user(page, 0, PAGE_CACHE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | SetPageUptodate(page); |
| 79 | unlock_page(page); |
| 80 | return 0; |
| 81 | } |
| 82 | |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 83 | static void nfs_readpage_truncate_uninitialised_page(struct nfs_read_data *data) |
| 84 | { |
| 85 | unsigned int remainder = data->args.count - data->res.count; |
| 86 | unsigned int base = data->args.pgbase + data->res.count; |
| 87 | unsigned int pglen; |
| 88 | struct page **pages; |
| 89 | |
| 90 | if (data->res.eof == 0 || remainder == 0) |
| 91 | return; |
| 92 | /* |
| 93 | * Note: "remainder" can never be negative, since we check for |
| 94 | * this in the XDR code. |
| 95 | */ |
| 96 | pages = &data->args.pages[base >> PAGE_CACHE_SHIFT]; |
| 97 | base &= ~PAGE_CACHE_MASK; |
| 98 | pglen = PAGE_CACHE_SIZE - base; |
Trond Myklebust | 79558f3 | 2006-08-22 13:44:32 -0400 | [diff] [blame] | 99 | for (;;) { |
| 100 | if (remainder <= pglen) { |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 101 | zero_user(*pages, base, remainder); |
Trond Myklebust | 79558f3 | 2006-08-22 13:44:32 -0400 | [diff] [blame] | 102 | break; |
| 103 | } |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 104 | zero_user(*pages, base, pglen); |
Trond Myklebust | 79558f3 | 2006-08-22 13:44:32 -0400 | [diff] [blame] | 105 | pages++; |
| 106 | remainder -= pglen; |
| 107 | pglen = PAGE_CACHE_SIZE; |
| 108 | base = 0; |
| 109 | } |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 110 | } |
| 111 | |
Trond Myklebust | 62e4a76 | 2011-11-10 14:30:37 -0500 | [diff] [blame^] | 112 | void nfs_pageio_init_read_mds(struct nfs_pageio_descriptor *pgio, |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 113 | struct inode *inode) |
| 114 | { |
| 115 | nfs_pageio_init(pgio, inode, &nfs_pageio_read_ops, |
| 116 | NFS_SERVER(inode)->rsize, 0); |
| 117 | } |
| 118 | |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 119 | void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio) |
| 120 | { |
| 121 | pgio->pg_ops = &nfs_pageio_read_ops; |
| 122 | pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->rsize; |
| 123 | } |
Trond Myklebust | 1f94535 | 2011-07-13 15:59:57 -0400 | [diff] [blame] | 124 | EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds); |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 125 | |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 126 | static void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, |
| 127 | struct inode *inode) |
| 128 | { |
| 129 | if (!pnfs_pageio_init_read(pgio, inode)) |
| 130 | nfs_pageio_init_read_mds(pgio, inode); |
| 131 | } |
| 132 | |
David Howells | f42b293 | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 133 | int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode, |
| 134 | struct page *page) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | struct nfs_page *new; |
| 137 | unsigned int len; |
Fred Isaman | c76069b | 2011-03-03 15:13:48 +0000 | [diff] [blame] | 138 | struct nfs_pageio_descriptor pgio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | |
Trond Myklebust | 49a70f2 | 2006-12-05 00:35:38 -0500 | [diff] [blame] | 140 | len = nfs_page_length(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | if (len == 0) |
| 142 | return nfs_return_empty_page(page); |
| 143 | new = nfs_create_request(ctx, inode, page, 0, len); |
| 144 | if (IS_ERR(new)) { |
| 145 | unlock_page(page); |
| 146 | return PTR_ERR(new); |
| 147 | } |
| 148 | if (len < PAGE_CACHE_SIZE) |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 149 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 151 | nfs_pageio_init_read(&pgio, inode); |
Trond Myklebust | d8007d4 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 152 | nfs_pageio_add_request(&pgio, new); |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 153 | nfs_pageio_complete(&pgio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | return 0; |
| 155 | } |
| 156 | |
| 157 | static void nfs_readpage_release(struct nfs_page *req) |
| 158 | { |
Al Viro | 3d4ff43 | 2011-06-22 18:40:12 -0400 | [diff] [blame] | 159 | struct inode *d_inode = req->wb_context->dentry->d_inode; |
David Howells | 7f8e05f | 2009-04-03 16:42:45 +0100 | [diff] [blame] | 160 | |
| 161 | if (PageUptodate(req->wb_page)) |
| 162 | nfs_readpage_to_fscache(d_inode, req->wb_page, 0); |
| 163 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | unlock_page(req->wb_page); |
| 165 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | dprintk("NFS: read done (%s/%Ld %d@%Ld)\n", |
Al Viro | 3d4ff43 | 2011-06-22 18:40:12 -0400 | [diff] [blame] | 167 | req->wb_context->dentry->d_inode->i_sb->s_id, |
| 168 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | req->wb_bytes, |
| 170 | (long long)req_offset(req)); |
Nick Wilson | 10d2c46 | 2005-09-22 21:44:28 -0700 | [diff] [blame] | 171 | nfs_release_request(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | } |
| 173 | |
Andy Adamson | dc70d7b | 2011-03-01 01:34:19 +0000 | [diff] [blame] | 174 | int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt, |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 175 | const struct rpc_call_ops *call_ops) |
| 176 | { |
| 177 | struct inode *inode = data->inode; |
| 178 | int swap_flags = IS_SWAPFILE(inode) ? NFS_RPC_SWAPFLAGS : 0; |
| 179 | struct rpc_task *task; |
| 180 | struct rpc_message msg = { |
| 181 | .rpc_argp = &data->args, |
| 182 | .rpc_resp = &data->res, |
| 183 | .rpc_cred = data->cred, |
| 184 | }; |
| 185 | struct rpc_task_setup task_setup_data = { |
| 186 | .task = &data->task, |
| 187 | .rpc_client = clnt, |
| 188 | .rpc_message = &msg, |
| 189 | .callback_ops = call_ops, |
| 190 | .callback_data = data, |
| 191 | .workqueue = nfsiod_workqueue, |
| 192 | .flags = RPC_TASK_ASYNC | swap_flags, |
| 193 | }; |
| 194 | |
| 195 | /* Set up the initial task struct. */ |
| 196 | NFS_PROTO(inode)->read_setup(data, &msg); |
| 197 | |
| 198 | dprintk("NFS: %5u initiated read call (req %s/%lld, %u bytes @ " |
| 199 | "offset %llu)\n", |
| 200 | data->task.tk_pid, |
| 201 | inode->i_sb->s_id, |
| 202 | (long long)NFS_FILEID(inode), |
| 203 | data->args.count, |
| 204 | (unsigned long long)data->args.offset); |
| 205 | |
| 206 | task = rpc_run_task(&task_setup_data); |
| 207 | if (IS_ERR(task)) |
| 208 | return PTR_ERR(task); |
| 209 | rpc_put_task(task); |
| 210 | return 0; |
| 211 | } |
Andy Adamson | dc70d7b | 2011-03-01 01:34:19 +0000 | [diff] [blame] | 212 | EXPORT_SYMBOL_GPL(nfs_initiate_read); |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 213 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | /* |
| 215 | * Set up the NFS read request struct |
| 216 | */ |
Trond Myklebust | 6e4efd5 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 217 | static void nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data, |
| 218 | unsigned int count, unsigned int offset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | { |
Al Viro | 3d4ff43 | 2011-06-22 18:40:12 -0400 | [diff] [blame] | 220 | struct inode *inode = req->wb_context->dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | |
| 222 | data->req = req; |
Trond Myklebust | 84115e1 | 2007-07-14 15:39:59 -0400 | [diff] [blame] | 223 | data->inode = inode; |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 224 | data->cred = req->wb_context->cred; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | |
| 226 | data->args.fh = NFS_FH(inode); |
| 227 | data->args.offset = req_offset(req) + offset; |
| 228 | data->args.pgbase = req->wb_pgbase + offset; |
| 229 | data->args.pages = data->pagevec; |
| 230 | data->args.count = count; |
Trond Myklebust | 383ba71 | 2008-02-19 20:04:20 -0500 | [diff] [blame] | 231 | data->args.context = get_nfs_open_context(req->wb_context); |
Trond Myklebust | f11ac8d | 2010-06-25 16:35:53 -0400 | [diff] [blame] | 232 | data->args.lock_context = req->wb_lock_context; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | |
| 234 | data->res.fattr = &data->fattr; |
| 235 | data->res.count = count; |
| 236 | data->res.eof = 0; |
Trond Myklebust | 0e574af | 2005-10-27 22:12:38 -0400 | [diff] [blame] | 237 | nfs_fattr_init(&data->fattr); |
Trond Myklebust | 6e4efd5 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 238 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | |
Trond Myklebust | 6e4efd5 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 240 | static int nfs_do_read(struct nfs_read_data *data, |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 241 | const struct rpc_call_ops *call_ops) |
Trond Myklebust | 6e4efd5 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 242 | { |
Stephen Rothwell | 5f00bcb | 2011-07-25 13:59:46 -0400 | [diff] [blame] | 243 | struct inode *inode = data->args.context->dentry->d_inode; |
Trond Myklebust | 6e4efd5 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 244 | |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 245 | return nfs_initiate_read(data, NFS_CLIENT(inode), call_ops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | } |
| 247 | |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 248 | static int |
| 249 | nfs_do_multiple_reads(struct list_head *head, |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 250 | const struct rpc_call_ops *call_ops) |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 251 | { |
| 252 | struct nfs_read_data *data; |
| 253 | int ret = 0; |
| 254 | |
| 255 | while (!list_empty(head)) { |
| 256 | int ret2; |
| 257 | |
| 258 | data = list_entry(head->next, struct nfs_read_data, list); |
| 259 | list_del_init(&data->list); |
| 260 | |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 261 | ret2 = nfs_do_read(data, call_ops); |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 262 | if (ret == 0) |
| 263 | ret = ret2; |
| 264 | } |
| 265 | return ret; |
| 266 | } |
| 267 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | static void |
| 269 | nfs_async_read_error(struct list_head *head) |
| 270 | { |
| 271 | struct nfs_page *req; |
| 272 | |
| 273 | while (!list_empty(head)) { |
| 274 | req = nfs_list_entry(head->next); |
| 275 | nfs_list_remove_request(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | nfs_readpage_release(req); |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | * Generate multiple requests to fill a single page. |
| 282 | * |
| 283 | * We optimize to reduce the number of read operations on the wire. If we |
| 284 | * detect that we're reading a page, or an area of a page, that is past the |
| 285 | * end of file, we do not generate NFS read operations but just clear the |
| 286 | * parts of the page that would have come back zero from the server anyway. |
| 287 | * |
| 288 | * We rely on the cached value of i_size to make this determination; another |
| 289 | * client can fill pages on the server past our cached end-of-file, but we |
| 290 | * won't see the new data until our attribute cache is updated. This is more |
| 291 | * or less conventional NFS client behavior. |
| 292 | */ |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 293 | static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc, struct list_head *res) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | { |
Fred Isaman | c76069b | 2011-03-03 15:13:48 +0000 | [diff] [blame] | 295 | struct nfs_page *req = nfs_list_entry(desc->pg_list.next); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | struct page *page = req->wb_page; |
| 297 | struct nfs_read_data *data; |
Trond Myklebust | d097971 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 298 | size_t rsize = desc->pg_bsize, nbytes; |
Trond Myklebust | e9f7bee | 2006-09-08 09:48:54 -0700 | [diff] [blame] | 299 | unsigned int offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | int requests = 0; |
Trond Myklebust | dbae4c7 | 2008-04-14 14:54:53 -0400 | [diff] [blame] | 301 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | |
| 303 | nfs_list_remove_request(req); |
| 304 | |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 305 | offset = 0; |
Fred Isaman | c76069b | 2011-03-03 15:13:48 +0000 | [diff] [blame] | 306 | nbytes = desc->pg_count; |
Trond Myklebust | e9f7bee | 2006-09-08 09:48:54 -0700 | [diff] [blame] | 307 | do { |
| 308 | size_t len = min(nbytes,rsize); |
| 309 | |
Trond Myklebust | 8d5658c | 2007-04-10 09:26:35 -0400 | [diff] [blame] | 310 | data = nfs_readdata_alloc(1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | if (!data) |
| 312 | goto out_bad; |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 313 | data->pagevec[0] = page; |
| 314 | nfs_read_rpcsetup(req, data, len, offset); |
| 315 | list_add(&data->list, res); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | requests++; |
Trond Myklebust | e9f7bee | 2006-09-08 09:48:54 -0700 | [diff] [blame] | 317 | nbytes -= len; |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 318 | offset += len; |
Trond Myklebust | e9f7bee | 2006-09-08 09:48:54 -0700 | [diff] [blame] | 319 | } while(nbytes != 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | atomic_set(&req->wb_complete, requests); |
Trond Myklebust | 50828d7 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 321 | desc->pg_rpc_callops = &nfs_read_partial_ops; |
Trond Myklebust | dbae4c7 | 2008-04-14 14:54:53 -0400 | [diff] [blame] | 322 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | out_bad: |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 324 | while (!list_empty(res)) { |
| 325 | data = list_entry(res->next, struct nfs_read_data, list); |
Trond Myklebust | 6e4efd5 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 326 | list_del(&data->list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | nfs_readdata_free(data); |
| 328 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | nfs_readpage_release(req); |
| 330 | return -ENOMEM; |
| 331 | } |
| 332 | |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 333 | static int nfs_pagein_one(struct nfs_pageio_descriptor *desc, struct list_head *res) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | { |
| 335 | struct nfs_page *req; |
| 336 | struct page **pages; |
| 337 | struct nfs_read_data *data; |
Fred Isaman | c76069b | 2011-03-03 15:13:48 +0000 | [diff] [blame] | 338 | struct list_head *head = &desc->pg_list; |
Peng Tao | 3b60918 | 2011-07-15 03:33:42 -0400 | [diff] [blame] | 339 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | |
Fred Isaman | c76069b | 2011-03-03 15:13:48 +0000 | [diff] [blame] | 341 | data = nfs_readdata_alloc(nfs_page_array_len(desc->pg_base, |
| 342 | desc->pg_count)); |
Fred Isaman | bae724e | 2011-03-01 01:34:15 +0000 | [diff] [blame] | 343 | if (!data) { |
| 344 | nfs_async_read_error(head); |
Peng Tao | 3b60918 | 2011-07-15 03:33:42 -0400 | [diff] [blame] | 345 | ret = -ENOMEM; |
Fred Isaman | bae724e | 2011-03-01 01:34:15 +0000 | [diff] [blame] | 346 | goto out; |
| 347 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | pages = data->pagevec; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | while (!list_empty(head)) { |
| 351 | req = nfs_list_entry(head->next); |
| 352 | nfs_list_remove_request(req); |
| 353 | nfs_list_add_request(req, &data->pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | *pages++ = req->wb_page; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | } |
| 356 | req = nfs_list_entry(data->pages.next); |
| 357 | |
Trond Myklebust | 6e4efd5 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 358 | nfs_read_rpcsetup(req, data, desc->pg_count, 0); |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 359 | list_add(&data->list, res); |
Trond Myklebust | 50828d7 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 360 | desc->pg_rpc_callops = &nfs_read_full_ops; |
Fred Isaman | bae724e | 2011-03-01 01:34:15 +0000 | [diff] [blame] | 361 | out: |
Trond Myklebust | dbae4c7 | 2008-04-14 14:54:53 -0400 | [diff] [blame] | 362 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | } |
| 364 | |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 365 | int nfs_generic_pagein(struct nfs_pageio_descriptor *desc, struct list_head *head) |
| 366 | { |
| 367 | if (desc->pg_bsize < PAGE_CACHE_SIZE) |
| 368 | return nfs_pagein_multi(desc, head); |
| 369 | return nfs_pagein_one(desc, head); |
| 370 | } |
| 371 | |
| 372 | static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc) |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 373 | { |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 374 | LIST_HEAD(head); |
| 375 | int ret; |
| 376 | |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 377 | ret = nfs_generic_pagein(desc, &head); |
Trond Myklebust | 50828d7 | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 378 | if (ret == 0) |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 379 | ret = nfs_do_multiple_reads(&head, desc->pg_rpc_callops); |
Trond Myklebust | 275acaa | 2011-07-12 13:42:02 -0400 | [diff] [blame] | 380 | return ret; |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 381 | } |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 382 | |
| 383 | static const struct nfs_pageio_ops nfs_pageio_read_ops = { |
| 384 | .pg_test = nfs_generic_pg_test, |
| 385 | .pg_doio = nfs_generic_pg_readpages, |
| 386 | }; |
| 387 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | /* |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 389 | * This is the callback from RPC telling us whether a reply was |
| 390 | * received or some error occurred (timeout or socket shutdown). |
| 391 | */ |
| 392 | int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data) |
| 393 | { |
| 394 | int status; |
| 395 | |
Harvey Harrison | 3110ff8 | 2008-05-02 13:42:44 -0700 | [diff] [blame] | 396 | dprintk("NFS: %s: %5u, (status %d)\n", __func__, task->tk_pid, |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 397 | task->tk_status); |
| 398 | |
| 399 | status = NFS_PROTO(data->inode)->read_done(task, data); |
| 400 | if (status != 0) |
| 401 | return status; |
| 402 | |
| 403 | nfs_add_stats(data->inode, NFSIOS_SERVERREADBYTES, data->res.count); |
| 404 | |
| 405 | if (task->tk_status == -ESTALE) { |
Benny Halevy | 3a10c30 | 2008-01-23 08:58:59 +0200 | [diff] [blame] | 406 | set_bit(NFS_INO_STALE, &NFS_I(data->inode)->flags); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 407 | nfs_mark_for_revalidate(data->inode); |
| 408 | } |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 409 | return 0; |
| 410 | } |
| 411 | |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 412 | static void nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data) |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 413 | { |
| 414 | struct nfs_readargs *argp = &data->args; |
| 415 | struct nfs_readres *resp = &data->res; |
| 416 | |
| 417 | if (resp->eof || resp->count == argp->count) |
Trond Myklebust | d61e612 | 2009-12-05 19:32:19 -0500 | [diff] [blame] | 418 | return; |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 419 | |
| 420 | /* This is a short read! */ |
| 421 | nfs_inc_stats(data->inode, NFSIOS_SHORTREAD); |
| 422 | /* Has the server at least made some progress? */ |
| 423 | if (resp->count == 0) |
Trond Myklebust | d61e612 | 2009-12-05 19:32:19 -0500 | [diff] [blame] | 424 | return; |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 425 | |
| 426 | /* Yes, so retry the read at the end of the data */ |
Andy Adamson | cbdabc7f | 2011-03-01 01:34:20 +0000 | [diff] [blame] | 427 | data->mds_offset += resp->count; |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 428 | argp->offset += resp->count; |
| 429 | argp->pgbase += resp->count; |
| 430 | argp->count -= resp->count; |
Trond Myklebust | d00c5d4 | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 431 | rpc_restart_call_prepare(task); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 432 | } |
| 433 | |
| 434 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 435 | * Handle a read reply that fills part of a page. |
| 436 | */ |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 437 | static void nfs_readpage_result_partial(struct rpc_task *task, void *calldata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | { |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 439 | struct nfs_read_data *data = calldata; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 441 | if (nfs_readpage_result(task, data) != 0) |
| 442 | return; |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 443 | if (task->tk_status < 0) |
| 444 | return; |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 445 | |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 446 | nfs_readpage_truncate_uninitialised_page(data); |
| 447 | nfs_readpage_retry(task, data); |
| 448 | } |
| 449 | |
| 450 | static void nfs_readpage_release_partial(void *calldata) |
| 451 | { |
| 452 | struct nfs_read_data *data = calldata; |
| 453 | struct nfs_page *req = data->req; |
| 454 | struct page *page = req->wb_page; |
| 455 | int status = data->task.tk_status; |
| 456 | |
| 457 | if (status < 0) |
Trond Myklebust | fba7300 | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 458 | set_bit(PG_PARTIAL_READ_FAILED, &req->wb_flags); |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 459 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 460 | if (atomic_dec_and_test(&req->wb_complete)) { |
Trond Myklebust | fba7300 | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 461 | if (!test_bit(PG_PARTIAL_READ_FAILED, &req->wb_flags)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | SetPageUptodate(page); |
| 463 | nfs_readpage_release(req); |
| 464 | } |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 465 | nfs_readdata_release(calldata); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | } |
| 467 | |
Andy Adamson | f11c88a | 2009-04-01 09:22:25 -0400 | [diff] [blame] | 468 | #if defined(CONFIG_NFS_V4_1) |
| 469 | void nfs_read_prepare(struct rpc_task *task, void *calldata) |
| 470 | { |
| 471 | struct nfs_read_data *data = calldata; |
| 472 | |
Trond Myklebust | 035168a | 2010-06-16 09:52:26 -0400 | [diff] [blame] | 473 | if (nfs4_setup_sequence(NFS_SERVER(data->inode), |
Andy Adamson | f11c88a | 2009-04-01 09:22:25 -0400 | [diff] [blame] | 474 | &data->args.seq_args, &data->res.seq_res, |
| 475 | 0, task)) |
| 476 | return; |
| 477 | rpc_call_start(task); |
| 478 | } |
| 479 | #endif /* CONFIG_NFS_V4_1 */ |
| 480 | |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 481 | static const struct rpc_call_ops nfs_read_partial_ops = { |
Andy Adamson | f11c88a | 2009-04-01 09:22:25 -0400 | [diff] [blame] | 482 | #if defined(CONFIG_NFS_V4_1) |
| 483 | .rpc_call_prepare = nfs_read_prepare, |
| 484 | #endif /* CONFIG_NFS_V4_1 */ |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 485 | .rpc_call_done = nfs_readpage_result_partial, |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 486 | .rpc_release = nfs_readpage_release_partial, |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 487 | }; |
| 488 | |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 489 | static void nfs_readpage_set_pages_uptodate(struct nfs_read_data *data) |
| 490 | { |
| 491 | unsigned int count = data->res.count; |
| 492 | unsigned int base = data->args.pgbase; |
| 493 | struct page **pages; |
| 494 | |
Trond Myklebust | 79558f3 | 2006-08-22 13:44:32 -0400 | [diff] [blame] | 495 | if (data->res.eof) |
| 496 | count = data->args.count; |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 497 | if (unlikely(count == 0)) |
| 498 | return; |
| 499 | pages = &data->args.pages[base >> PAGE_CACHE_SHIFT]; |
| 500 | base &= ~PAGE_CACHE_MASK; |
| 501 | count += base; |
| 502 | for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++) |
| 503 | SetPageUptodate(*pages); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 504 | if (count == 0) |
| 505 | return; |
| 506 | /* Was this a short read? */ |
| 507 | if (data->res.eof || data->res.count == data->args.count) |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 508 | SetPageUptodate(*pages); |
| 509 | } |
| 510 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | /* |
| 512 | * This is the callback from RPC telling us whether a reply was |
| 513 | * received or some error occurred (timeout or socket shutdown). |
| 514 | */ |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 515 | static void nfs_readpage_result_full(struct rpc_task *task, void *calldata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 516 | { |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 517 | struct nfs_read_data *data = calldata; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 519 | if (nfs_readpage_result(task, data) != 0) |
| 520 | return; |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 521 | if (task->tk_status < 0) |
| 522 | return; |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 523 | /* |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 524 | * Note: nfs_readpage_retry may change the values of |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 525 | * data->args. In the multi-page case, we therefore need |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 526 | * to ensure that we call nfs_readpage_set_pages_uptodate() |
| 527 | * first. |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 528 | */ |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 529 | nfs_readpage_truncate_uninitialised_page(data); |
| 530 | nfs_readpage_set_pages_uptodate(data); |
| 531 | nfs_readpage_retry(task, data); |
| 532 | } |
| 533 | |
| 534 | static void nfs_readpage_release_full(void *calldata) |
| 535 | { |
| 536 | struct nfs_read_data *data = calldata; |
| 537 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 538 | while (!list_empty(&data->pages)) { |
| 539 | struct nfs_page *req = nfs_list_entry(data->pages.next); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 540 | |
Trond Myklebust | 1de3fc1 | 2006-05-25 01:40:44 -0400 | [diff] [blame] | 541 | nfs_list_remove_request(req); |
Trond Myklebust | 62e4a76 | 2011-11-10 14:30:37 -0500 | [diff] [blame^] | 542 | nfs_readpage_release(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 543 | } |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 544 | nfs_readdata_release(calldata); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 545 | } |
| 546 | |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 547 | static const struct rpc_call_ops nfs_read_full_ops = { |
Andy Adamson | f11c88a | 2009-04-01 09:22:25 -0400 | [diff] [blame] | 548 | #if defined(CONFIG_NFS_V4_1) |
| 549 | .rpc_call_prepare = nfs_read_prepare, |
| 550 | #endif /* CONFIG_NFS_V4_1 */ |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 551 | .rpc_call_done = nfs_readpage_result_full, |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 552 | .rpc_release = nfs_readpage_release_full, |
Trond Myklebust | ec06c09 | 2006-03-20 13:44:27 -0500 | [diff] [blame] | 553 | }; |
| 554 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | * Read a page over NFS. |
| 557 | * We read the page synchronously in the following case: |
| 558 | * - The error flag is set for this page. This happens only when a |
| 559 | * previous async read operation failed. |
| 560 | */ |
| 561 | int nfs_readpage(struct file *file, struct page *page) |
| 562 | { |
| 563 | struct nfs_open_context *ctx; |
| 564 | struct inode *inode = page->mapping->host; |
| 565 | int error; |
| 566 | |
| 567 | dprintk("NFS: nfs_readpage (%p %ld@%lu)\n", |
| 568 | page, PAGE_CACHE_SIZE, page->index); |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 569 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGE); |
| 570 | nfs_add_stats(inode, NFSIOS_READPAGES, 1); |
| 571 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 572 | /* |
| 573 | * Try to flush any pending writes to the file.. |
| 574 | * |
| 575 | * NOTE! Because we own the page lock, there cannot |
| 576 | * be any new pending writes generated at this point |
| 577 | * for this page (other pages can be written to). |
| 578 | */ |
| 579 | error = nfs_wb_page(inode, page); |
| 580 | if (error) |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 581 | goto out_unlock; |
| 582 | if (PageUptodate(page)) |
| 583 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 585 | error = -ESTALE; |
| 586 | if (NFS_STALE(inode)) |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 587 | goto out_unlock; |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 588 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | if (file == NULL) { |
Trond Myklebust | cf1308f | 2006-11-19 16:44:52 -0500 | [diff] [blame] | 590 | error = -EBADF; |
Trond Myklebust | d530838 | 2005-11-04 15:33:38 -0500 | [diff] [blame] | 591 | ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | if (ctx == NULL) |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 593 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | } else |
Trond Myklebust | cd3758e | 2007-08-10 17:44:32 -0400 | [diff] [blame] | 595 | ctx = get_nfs_open_context(nfs_file_open_context(file)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 597 | if (!IS_SYNC(inode)) { |
| 598 | error = nfs_readpage_from_fscache(ctx, inode, page); |
| 599 | if (error == 0) |
| 600 | goto out; |
| 601 | } |
| 602 | |
Trond Myklebust | 8e0969f | 2006-12-13 15:23:44 -0500 | [diff] [blame] | 603 | error = nfs_readpage_async(ctx, inode, page); |
| 604 | |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 605 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 606 | put_nfs_open_context(ctx); |
| 607 | return error; |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 608 | out_unlock: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | unlock_page(page); |
| 610 | return error; |
| 611 | } |
| 612 | |
| 613 | struct nfs_readdesc { |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 614 | struct nfs_pageio_descriptor *pgio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | struct nfs_open_context *ctx; |
| 616 | }; |
| 617 | |
| 618 | static int |
| 619 | readpage_async_filler(void *data, struct page *page) |
| 620 | { |
| 621 | struct nfs_readdesc *desc = (struct nfs_readdesc *)data; |
| 622 | struct inode *inode = page->mapping->host; |
| 623 | struct nfs_page *new; |
| 624 | unsigned int len; |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 625 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | |
Trond Myklebust | 49a70f2 | 2006-12-05 00:35:38 -0500 | [diff] [blame] | 627 | len = nfs_page_length(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 628 | if (len == 0) |
| 629 | return nfs_return_empty_page(page); |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 630 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | new = nfs_create_request(desc->ctx, inode, page, 0, len); |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 632 | if (IS_ERR(new)) |
| 633 | goto out_error; |
| 634 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | if (len < PAGE_CACHE_SIZE) |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 636 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
Fred Isaman | f8512ad | 2008-03-19 11:24:39 -0400 | [diff] [blame] | 637 | if (!nfs_pageio_add_request(desc->pgio, new)) { |
| 638 | error = desc->pgio->pg_error; |
| 639 | goto out_unlock; |
| 640 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | return 0; |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 642 | out_error: |
| 643 | error = PTR_ERR(new); |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 644 | out_unlock: |
| 645 | unlock_page(page); |
| 646 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | } |
| 648 | |
| 649 | int nfs_readpages(struct file *filp, struct address_space *mapping, |
| 650 | struct list_head *pages, unsigned nr_pages) |
| 651 | { |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 652 | struct nfs_pageio_descriptor pgio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | struct nfs_readdesc desc = { |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 654 | .pgio = &pgio, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | }; |
| 656 | struct inode *inode = mapping->host; |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 657 | unsigned long npages; |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 658 | int ret = -ESTALE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | |
| 660 | dprintk("NFS: nfs_readpages (%s/%Ld %d)\n", |
| 661 | inode->i_sb->s_id, |
| 662 | (long long)NFS_FILEID(inode), |
| 663 | nr_pages); |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 664 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGES); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 666 | if (NFS_STALE(inode)) |
| 667 | goto out; |
| 668 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | if (filp == NULL) { |
Trond Myklebust | d530838 | 2005-11-04 15:33:38 -0500 | [diff] [blame] | 670 | desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | if (desc.ctx == NULL) |
| 672 | return -EBADF; |
| 673 | } else |
Trond Myklebust | cd3758e | 2007-08-10 17:44:32 -0400 | [diff] [blame] | 674 | desc.ctx = get_nfs_open_context(nfs_file_open_context(filp)); |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 675 | |
| 676 | /* attempt to read as many of the pages as possible from the cache |
| 677 | * - this returns -ENOBUFS immediately if the cookie is negative |
| 678 | */ |
| 679 | ret = nfs_readpages_from_fscache(desc.ctx, inode, mapping, |
| 680 | pages, &nr_pages); |
| 681 | if (ret == 0) |
| 682 | goto read_complete; /* all pages were read */ |
| 683 | |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 684 | nfs_pageio_init_read(&pgio, inode); |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 685 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc); |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 687 | |
| 688 | nfs_pageio_complete(&pgio); |
| 689 | npages = (pgio.pg_bytes_written + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
| 690 | nfs_add_stats(inode, NFSIOS_READPAGES, npages); |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 691 | read_complete: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | put_nfs_open_context(desc.ctx); |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 693 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | return ret; |
| 695 | } |
| 696 | |
David Howells | f7b422b | 2006-06-09 09:34:33 -0400 | [diff] [blame] | 697 | int __init nfs_init_readpagecache(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | { |
| 699 | nfs_rdata_cachep = kmem_cache_create("nfs_read_data", |
| 700 | sizeof(struct nfs_read_data), |
| 701 | 0, SLAB_HWCACHE_ALIGN, |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 702 | NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | if (nfs_rdata_cachep == NULL) |
| 704 | return -ENOMEM; |
| 705 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | return 0; |
| 707 | } |
| 708 | |
David Brownell | 266bee8 | 2006-06-27 12:59:15 -0700 | [diff] [blame] | 709 | void nfs_destroy_readpagecache(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | { |
Alexey Dobriyan | 1a1d92c | 2006-09-27 01:49:40 -0700 | [diff] [blame] | 711 | kmem_cache_destroy(nfs_rdata_cachep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | } |