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 | |
Andy Adamson | f11c88a | 2009-04-01 09:22:25 -0400 | [diff] [blame] | 23 | #include "nfs4_fs.h" |
Trond Myklebust | 49a70f2 | 2006-12-05 00:35:38 -0500 | [diff] [blame] | 24 | #include "internal.h" |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 25 | #include "iostat.h" |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 26 | #include "fscache.h" |
Christoph Hellwig | fab5fc2 | 2014-04-16 15:07:22 +0200 | [diff] [blame] | 27 | #include "pnfs.h" |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 28 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE |
| 30 | |
Fred Isaman | 061ae2e | 2012-04-20 14:47:48 -0400 | [diff] [blame] | 31 | static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops; |
Anna Schumaker | 4a0de55 | 2014-05-06 09:12:30 -0400 | [diff] [blame] | 32 | static const struct nfs_rw_ops nfs_rw_read_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 34 | static struct kmem_cache *nfs_rdata_cachep; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
Weston Andros Adamson | 1e7f3a4 | 2014-06-09 11:48:33 -0400 | [diff] [blame] | 36 | static struct nfs_pgio_header *nfs_readhdr_alloc(void) |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 37 | { |
Anna Schumaker | 4a0de55 | 2014-05-06 09:12:30 -0400 | [diff] [blame] | 38 | return kmem_cache_zalloc(nfs_rdata_cachep, GFP_KERNEL); |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 39 | } |
| 40 | |
Weston Andros Adamson | 1e7f3a4 | 2014-06-09 11:48:33 -0400 | [diff] [blame] | 41 | static void nfs_readhdr_free(struct nfs_pgio_header *rhdr) |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 42 | { |
Fred Isaman | cd84160 | 2012-04-20 14:47:44 -0400 | [diff] [blame] | 43 | kmem_cache_free(nfs_rdata_cachep, rhdr); |
Trond Myklebust | 3feb2d4 | 2006-03-20 13:44:37 -0500 | [diff] [blame] | 44 | } |
| 45 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | static |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | int nfs_return_empty_page(struct page *page) |
| 48 | { |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 49 | zero_user(page, 0, PAGE_CACHE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | SetPageUptodate(page); |
| 51 | unlock_page(page); |
| 52 | return 0; |
| 53 | } |
| 54 | |
Bryan Schumaker | 1abb5088 | 2012-06-20 15:53:47 -0400 | [diff] [blame] | 55 | void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, |
Christoph Hellwig | fab5fc2 | 2014-04-16 15:07:22 +0200 | [diff] [blame] | 56 | struct inode *inode, bool force_mds, |
Fred Isaman | 061ae2e | 2012-04-20 14:47:48 -0400 | [diff] [blame] | 57 | const struct nfs_pgio_completion_ops *compl_ops) |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 58 | { |
Christoph Hellwig | fab5fc2 | 2014-04-16 15:07:22 +0200 | [diff] [blame] | 59 | struct nfs_server *server = NFS_SERVER(inode); |
Anna Schumaker | 41d8d5b | 2014-05-06 09:12:40 -0400 | [diff] [blame] | 60 | const struct nfs_pageio_ops *pg_ops = &nfs_pgio_rw_ops; |
Christoph Hellwig | fab5fc2 | 2014-04-16 15:07:22 +0200 | [diff] [blame] | 61 | |
| 62 | #ifdef CONFIG_NFS_V4_1 |
| 63 | if (server->pnfs_curr_ld && !force_mds) |
| 64 | pg_ops = server->pnfs_curr_ld->pg_read_ops; |
| 65 | #endif |
Anna Schumaker | 4a0de55 | 2014-05-06 09:12:30 -0400 | [diff] [blame] | 66 | nfs_pageio_init(pgio, inode, pg_ops, compl_ops, &nfs_rw_read_ops, |
| 67 | server->rsize, 0); |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 68 | } |
Bryan Schumaker | ddda8e0 | 2012-07-30 16:05:23 -0400 | [diff] [blame] | 69 | EXPORT_SYMBOL_GPL(nfs_pageio_init_read); |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 70 | |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 71 | void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio) |
| 72 | { |
Anna Schumaker | 41d8d5b | 2014-05-06 09:12:40 -0400 | [diff] [blame] | 73 | pgio->pg_ops = &nfs_pgio_rw_ops; |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 74 | pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->rsize; |
| 75 | } |
Trond Myklebust | 1f94535 | 2011-07-13 15:59:57 -0400 | [diff] [blame] | 76 | EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds); |
Trond Myklebust | 493292d | 2011-07-13 15:58:28 -0400 | [diff] [blame] | 77 | |
David Howells | f42b293 | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 78 | int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode, |
| 79 | struct page *page) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | struct nfs_page *new; |
| 82 | unsigned int len; |
Fred Isaman | c76069b | 2011-03-03 15:13:48 +0000 | [diff] [blame] | 83 | struct nfs_pageio_descriptor pgio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | |
Trond Myklebust | 49a70f2 | 2006-12-05 00:35:38 -0500 | [diff] [blame] | 85 | len = nfs_page_length(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | if (len == 0) |
| 87 | return nfs_return_empty_page(page); |
Weston Andros Adamson | 2bfc6e5 | 2014-05-15 11:56:45 -0400 | [diff] [blame] | 88 | new = nfs_create_request(ctx, page, NULL, 0, len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | if (IS_ERR(new)) { |
| 90 | unlock_page(page); |
| 91 | return PTR_ERR(new); |
| 92 | } |
| 93 | if (len < PAGE_CACHE_SIZE) |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 94 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | |
Christoph Hellwig | fab5fc2 | 2014-04-16 15:07:22 +0200 | [diff] [blame] | 96 | nfs_pageio_init_read(&pgio, inode, false, |
| 97 | &nfs_async_read_completion_ops); |
Trond Myklebust | d8007d4 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 98 | nfs_pageio_add_request(&pgio, new); |
Trond Myklebust | 1751c36 | 2011-06-10 13:30:23 -0400 | [diff] [blame] | 99 | nfs_pageio_complete(&pgio); |
Andy Adamson | 2701d08 | 2012-05-24 13:13:24 -0400 | [diff] [blame] | 100 | NFS_I(inode)->read_io += pgio.pg_bytes_written; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | static void nfs_readpage_release(struct nfs_page *req) |
| 105 | { |
Al Viro | 3d4ff43 | 2011-06-22 18:40:12 -0400 | [diff] [blame] | 106 | struct inode *d_inode = req->wb_context->dentry->d_inode; |
David Howells | 7f8e05f | 2009-04-03 16:42:45 +0100 | [diff] [blame] | 107 | |
Weston Andros Adamson | 67d0338 | 2014-05-15 11:56:46 -0400 | [diff] [blame] | 108 | dprintk("NFS: read done (%s/%llu %d@%lld)\n", d_inode->i_sb->s_id, |
| 109 | (unsigned long long)NFS_FILEID(d_inode), req->wb_bytes, |
| 110 | (long long)req_offset(req)); |
David Howells | 7f8e05f | 2009-04-03 16:42:45 +0100 | [diff] [blame] | 111 | |
Weston Andros Adamson | 67d0338 | 2014-05-15 11:56:46 -0400 | [diff] [blame] | 112 | if (nfs_page_group_sync_on_bit(req, PG_UNLOCKPAGE)) { |
| 113 | if (PageUptodate(req->wb_page)) |
| 114 | nfs_readpage_to_fscache(d_inode, req->wb_page, 0); |
| 115 | |
| 116 | unlock_page(req->wb_page); |
| 117 | } |
Nick Wilson | 10d2c46 | 2005-09-22 21:44:28 -0700 | [diff] [blame] | 118 | nfs_release_request(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | } |
| 120 | |
Weston Andros Adamson | 67d0338 | 2014-05-15 11:56:46 -0400 | [diff] [blame] | 121 | static void nfs_page_group_set_uptodate(struct nfs_page *req) |
| 122 | { |
| 123 | if (nfs_page_group_sync_on_bit(req, PG_UPTODATE)) |
| 124 | SetPageUptodate(req->wb_page); |
| 125 | } |
| 126 | |
Fred Isaman | 061ae2e | 2012-04-20 14:47:48 -0400 | [diff] [blame] | 127 | static void nfs_read_completion(struct nfs_pgio_header *hdr) |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 128 | { |
| 129 | unsigned long bytes = 0; |
| 130 | |
| 131 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) |
| 132 | goto out; |
Trond Myklebust | 4bd8b01 | 2012-05-01 12:49:58 -0400 | [diff] [blame] | 133 | while (!list_empty(&hdr->pages)) { |
| 134 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); |
| 135 | struct page *page = req->wb_page; |
Weston Andros Adamson | 6807299 | 2014-05-15 11:56:57 -0400 | [diff] [blame] | 136 | unsigned long start = req->wb_pgbase; |
| 137 | unsigned long end = req->wb_pgbase + req->wb_bytes; |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 138 | |
Trond Myklebust | 4bd8b01 | 2012-05-01 12:49:58 -0400 | [diff] [blame] | 139 | if (test_bit(NFS_IOHDR_EOF, &hdr->flags)) { |
Weston Andros Adamson | 6807299 | 2014-05-15 11:56:57 -0400 | [diff] [blame] | 140 | /* note: regions of the page not covered by a |
| 141 | * request are zeroed in nfs_readpage_async / |
| 142 | * readpage_async_filler */ |
| 143 | if (bytes > hdr->good_bytes) { |
| 144 | /* nothing in this request was good, so zero |
| 145 | * the full extent of the request */ |
| 146 | zero_user_segment(page, start, end); |
| 147 | |
| 148 | } else if (hdr->good_bytes - bytes < req->wb_bytes) { |
| 149 | /* part of this request has good bytes, but |
| 150 | * not all. zero the bad bytes */ |
| 151 | start += hdr->good_bytes - bytes; |
| 152 | WARN_ON(start < req->wb_pgbase); |
| 153 | zero_user_segment(page, start, end); |
| 154 | } |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 155 | } |
Trond Myklebust | 4bd8b01 | 2012-05-01 12:49:58 -0400 | [diff] [blame] | 156 | bytes += req->wb_bytes; |
| 157 | if (test_bit(NFS_IOHDR_ERROR, &hdr->flags)) { |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 158 | if (bytes <= hdr->good_bytes) |
Weston Andros Adamson | 67d0338 | 2014-05-15 11:56:46 -0400 | [diff] [blame] | 159 | nfs_page_group_set_uptodate(req); |
Trond Myklebust | 4bd8b01 | 2012-05-01 12:49:58 -0400 | [diff] [blame] | 160 | } else |
Weston Andros Adamson | 67d0338 | 2014-05-15 11:56:46 -0400 | [diff] [blame] | 161 | nfs_page_group_set_uptodate(req); |
Trond Myklebust | 4bd8b01 | 2012-05-01 12:49:58 -0400 | [diff] [blame] | 162 | nfs_list_remove_request(req); |
| 163 | nfs_readpage_release(req); |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 164 | } |
| 165 | out: |
| 166 | hdr->release(hdr); |
| 167 | } |
| 168 | |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 169 | static void nfs_initiate_read(struct nfs_pgio_header *hdr, |
| 170 | struct rpc_message *msg, |
Anna Schumaker | 1ed26f3 | 2014-05-06 09:12:37 -0400 | [diff] [blame] | 171 | struct rpc_task_setup *task_setup_data, int how) |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 172 | { |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 173 | struct inode *inode = hdr->inode; |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 174 | int swap_flags = IS_SWAPFILE(inode) ? NFS_RPC_SWAPFLAGS : 0; |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 175 | |
Anna Schumaker | 1ed26f3 | 2014-05-06 09:12:37 -0400 | [diff] [blame] | 176 | task_setup_data->flags |= swap_flags; |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 177 | NFS_PROTO(inode)->read_setup(hdr, msg); |
Andy Adamson | 64419a9 | 2011-03-01 01:34:16 +0000 | [diff] [blame] | 178 | } |
| 179 | |
Fred Isaman | 061ae2e | 2012-04-20 14:47:48 -0400 | [diff] [blame] | 180 | static void |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | nfs_async_read_error(struct list_head *head) |
| 182 | { |
| 183 | struct nfs_page *req; |
| 184 | |
| 185 | while (!list_empty(head)) { |
| 186 | req = nfs_list_entry(head->next); |
| 187 | nfs_list_remove_request(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | nfs_readpage_release(req); |
| 189 | } |
| 190 | } |
| 191 | |
Fred Isaman | 061ae2e | 2012-04-20 14:47:48 -0400 | [diff] [blame] | 192 | static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops = { |
| 193 | .error_cleanup = nfs_async_read_error, |
| 194 | .completion = nfs_read_completion, |
| 195 | }; |
| 196 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | /* |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 198 | * This is the callback from RPC telling us whether a reply was |
| 199 | * received or some error occurred (timeout or socket shutdown). |
| 200 | */ |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 201 | static int nfs_readpage_done(struct rpc_task *task, |
| 202 | struct nfs_pgio_header *hdr, |
Anna Schumaker | 0eecb21 | 2014-05-06 09:12:32 -0400 | [diff] [blame] | 203 | struct inode *inode) |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 204 | { |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 205 | int status = NFS_PROTO(inode)->read_done(task, hdr); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 206 | if (status != 0) |
| 207 | return status; |
| 208 | |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 209 | nfs_add_stats(inode, NFSIOS_SERVERREADBYTES, hdr->res.count); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 210 | |
| 211 | if (task->tk_status == -ESTALE) { |
Fred Isaman | cd84160 | 2012-04-20 14:47:44 -0400 | [diff] [blame] | 212 | set_bit(NFS_INO_STALE, &NFS_I(inode)->flags); |
| 213 | nfs_mark_for_revalidate(inode); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 214 | } |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 215 | return 0; |
| 216 | } |
| 217 | |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 218 | static void nfs_readpage_retry(struct rpc_task *task, |
| 219 | struct nfs_pgio_header *hdr) |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 220 | { |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 221 | struct nfs_pgio_args *argp = &hdr->args; |
| 222 | struct nfs_pgio_res *resp = &hdr->res; |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 223 | |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 224 | /* This is a short read! */ |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 225 | nfs_inc_stats(hdr->inode, NFSIOS_SHORTREAD); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 226 | /* Has the server at least made some progress? */ |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 227 | if (resp->count == 0) { |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 228 | nfs_set_pgio_error(hdr, -EIO, argp->offset); |
Trond Myklebust | d61e612 | 2009-12-05 19:32:19 -0500 | [diff] [blame] | 229 | return; |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 230 | } |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 231 | /* Yes, so retry the read at the end of the hdr */ |
| 232 | hdr->mds_offset += resp->count; |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 233 | argp->offset += resp->count; |
| 234 | argp->pgbase += resp->count; |
| 235 | argp->count -= resp->count; |
Trond Myklebust | d00c5d4 | 2011-10-19 12:17:29 -0700 | [diff] [blame] | 236 | rpc_restart_call_prepare(task); |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 237 | } |
| 238 | |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 239 | static void nfs_readpage_result(struct rpc_task *task, |
| 240 | struct nfs_pgio_header *hdr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | { |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 242 | if (hdr->res.eof) { |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 243 | loff_t bound; |
Trond Myklebust | 0b67130 | 2006-11-14 16:12:23 -0500 | [diff] [blame] | 244 | |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 245 | bound = hdr->args.offset + hdr->res.count; |
Fred Isaman | 4db6e0b | 2012-04-20 14:47:46 -0400 | [diff] [blame] | 246 | spin_lock(&hdr->lock); |
| 247 | if (bound < hdr->io_start + hdr->good_bytes) { |
| 248 | set_bit(NFS_IOHDR_EOF, &hdr->flags); |
| 249 | clear_bit(NFS_IOHDR_ERROR, &hdr->flags); |
| 250 | hdr->good_bytes = bound - hdr->io_start; |
| 251 | } |
| 252 | spin_unlock(&hdr->lock); |
Weston Andros Adamson | d45f60c | 2014-06-09 11:48:35 -0400 | [diff] [blame] | 253 | } else if (hdr->res.count != hdr->args.count) |
| 254 | nfs_readpage_retry(task, hdr); |
Trond Myklebust | fdd1e74 | 2008-04-15 16:33:58 -0400 | [diff] [blame] | 255 | } |
| 256 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | * Read a page over NFS. |
| 259 | * We read the page synchronously in the following case: |
| 260 | * - The error flag is set for this page. This happens only when a |
| 261 | * previous async read operation failed. |
| 262 | */ |
| 263 | int nfs_readpage(struct file *file, struct page *page) |
| 264 | { |
| 265 | struct nfs_open_context *ctx; |
Mel Gorman | d56b4dd | 2012-07-31 16:45:06 -0700 | [diff] [blame] | 266 | struct inode *inode = page_file_mapping(page)->host; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | int error; |
| 268 | |
| 269 | dprintk("NFS: nfs_readpage (%p %ld@%lu)\n", |
Mel Gorman | d56b4dd | 2012-07-31 16:45:06 -0700 | [diff] [blame] | 270 | page, PAGE_CACHE_SIZE, page_file_index(page)); |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 271 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGE); |
| 272 | nfs_add_stats(inode, NFSIOS_READPAGES, 1); |
| 273 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | /* |
| 275 | * Try to flush any pending writes to the file.. |
| 276 | * |
| 277 | * NOTE! Because we own the page lock, there cannot |
| 278 | * be any new pending writes generated at this point |
| 279 | * for this page (other pages can be written to). |
| 280 | */ |
| 281 | error = nfs_wb_page(inode, page); |
| 282 | if (error) |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 283 | goto out_unlock; |
| 284 | if (PageUptodate(page)) |
| 285 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 287 | error = -ESTALE; |
| 288 | if (NFS_STALE(inode)) |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 289 | goto out_unlock; |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 290 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | if (file == NULL) { |
Trond Myklebust | cf1308f | 2006-11-19 16:44:52 -0500 | [diff] [blame] | 292 | error = -EBADF; |
Trond Myklebust | d530838 | 2005-11-04 15:33:38 -0500 | [diff] [blame] | 293 | ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | if (ctx == NULL) |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 295 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | } else |
Trond Myklebust | cd3758e | 2007-08-10 17:44:32 -0400 | [diff] [blame] | 297 | ctx = get_nfs_open_context(nfs_file_open_context(file)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 299 | if (!IS_SYNC(inode)) { |
| 300 | error = nfs_readpage_from_fscache(ctx, inode, page); |
| 301 | if (error == 0) |
| 302 | goto out; |
| 303 | } |
| 304 | |
Trond Myklebust | 8e0969f | 2006-12-13 15:23:44 -0500 | [diff] [blame] | 305 | error = nfs_readpage_async(ctx, inode, page); |
| 306 | |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 307 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 308 | put_nfs_open_context(ctx); |
| 309 | return error; |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 310 | out_unlock: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | unlock_page(page); |
| 312 | return error; |
| 313 | } |
| 314 | |
| 315 | struct nfs_readdesc { |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 316 | struct nfs_pageio_descriptor *pgio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | struct nfs_open_context *ctx; |
| 318 | }; |
| 319 | |
| 320 | static int |
| 321 | readpage_async_filler(void *data, struct page *page) |
| 322 | { |
| 323 | struct nfs_readdesc *desc = (struct nfs_readdesc *)data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | struct nfs_page *new; |
| 325 | unsigned int len; |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 326 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | |
Trond Myklebust | 49a70f2 | 2006-12-05 00:35:38 -0500 | [diff] [blame] | 328 | len = nfs_page_length(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | if (len == 0) |
| 330 | return nfs_return_empty_page(page); |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 331 | |
Weston Andros Adamson | 2bfc6e5 | 2014-05-15 11:56:45 -0400 | [diff] [blame] | 332 | new = nfs_create_request(desc->ctx, page, NULL, 0, len); |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 333 | if (IS_ERR(new)) |
| 334 | goto out_error; |
| 335 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | if (len < PAGE_CACHE_SIZE) |
Christoph Lameter | eebd2aa | 2008-02-04 22:28:29 -0800 | [diff] [blame] | 337 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
Fred Isaman | f8512ad | 2008-03-19 11:24:39 -0400 | [diff] [blame] | 338 | if (!nfs_pageio_add_request(desc->pgio, new)) { |
| 339 | error = desc->pgio->pg_error; |
| 340 | goto out_unlock; |
| 341 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | return 0; |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 343 | out_error: |
| 344 | error = PTR_ERR(new); |
Trond Myklebust | de05a0c | 2007-05-20 13:05:05 -0400 | [diff] [blame] | 345 | out_unlock: |
| 346 | unlock_page(page); |
| 347 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | } |
| 349 | |
| 350 | int nfs_readpages(struct file *filp, struct address_space *mapping, |
| 351 | struct list_head *pages, unsigned nr_pages) |
| 352 | { |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 353 | struct nfs_pageio_descriptor pgio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | struct nfs_readdesc desc = { |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 355 | .pgio = &pgio, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | }; |
| 357 | struct inode *inode = mapping->host; |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 358 | unsigned long npages; |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 359 | int ret = -ESTALE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | |
Niels de Vos | 1e8968c | 2013-12-17 18:20:16 +0100 | [diff] [blame] | 361 | dprintk("NFS: nfs_readpages (%s/%Lu %d)\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | inode->i_sb->s_id, |
Niels de Vos | 1e8968c | 2013-12-17 18:20:16 +0100 | [diff] [blame] | 363 | (unsigned long long)NFS_FILEID(inode), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | nr_pages); |
Chuck Lever | 91d5b47 | 2006-03-20 13:44:14 -0500 | [diff] [blame] | 365 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGES); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 367 | if (NFS_STALE(inode)) |
| 368 | goto out; |
| 369 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 370 | if (filp == NULL) { |
Trond Myklebust | d530838 | 2005-11-04 15:33:38 -0500 | [diff] [blame] | 371 | desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | if (desc.ctx == NULL) |
| 373 | return -EBADF; |
| 374 | } else |
Trond Myklebust | cd3758e | 2007-08-10 17:44:32 -0400 | [diff] [blame] | 375 | desc.ctx = get_nfs_open_context(nfs_file_open_context(filp)); |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 376 | |
| 377 | /* attempt to read as many of the pages as possible from the cache |
| 378 | * - this returns -ENOBUFS immediately if the cookie is negative |
| 379 | */ |
| 380 | ret = nfs_readpages_from_fscache(desc.ctx, inode, mapping, |
| 381 | pages, &nr_pages); |
| 382 | if (ret == 0) |
| 383 | goto read_complete; /* all pages were read */ |
| 384 | |
Christoph Hellwig | fab5fc2 | 2014-04-16 15:07:22 +0200 | [diff] [blame] | 385 | nfs_pageio_init_read(&pgio, inode, false, |
| 386 | &nfs_async_read_completion_ops); |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 387 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc); |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 389 | |
| 390 | nfs_pageio_complete(&pgio); |
Andy Adamson | 2701d08 | 2012-05-24 13:13:24 -0400 | [diff] [blame] | 391 | NFS_I(inode)->read_io += pgio.pg_bytes_written; |
Trond Myklebust | 8b09bee | 2007-04-02 18:48:28 -0400 | [diff] [blame] | 392 | npages = (pgio.pg_bytes_written + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
| 393 | nfs_add_stats(inode, NFSIOS_READPAGES, npages); |
David Howells | 9a9fc1c | 2009-04-03 16:42:44 +0100 | [diff] [blame] | 394 | read_complete: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | put_nfs_open_context(desc.ctx); |
Trond Myklebust | 5f004cf | 2006-09-14 14:03:14 -0400 | [diff] [blame] | 396 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | return ret; |
| 398 | } |
| 399 | |
David Howells | f7b422b | 2006-06-09 09:34:33 -0400 | [diff] [blame] | 400 | int __init nfs_init_readpagecache(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 401 | { |
| 402 | nfs_rdata_cachep = kmem_cache_create("nfs_read_data", |
Weston Andros Adamson | 1e7f3a4 | 2014-06-09 11:48:33 -0400 | [diff] [blame] | 403 | sizeof(struct nfs_pgio_header), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | 0, SLAB_HWCACHE_ALIGN, |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 405 | NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | if (nfs_rdata_cachep == NULL) |
| 407 | return -ENOMEM; |
| 408 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | return 0; |
| 410 | } |
| 411 | |
David Brownell | 266bee8 | 2006-06-27 12:59:15 -0700 | [diff] [blame] | 412 | void nfs_destroy_readpagecache(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | { |
Alexey Dobriyan | 1a1d92c | 2006-09-27 01:49:40 -0700 | [diff] [blame] | 414 | kmem_cache_destroy(nfs_rdata_cachep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | } |
Anna Schumaker | 4a0de55 | 2014-05-06 09:12:30 -0400 | [diff] [blame] | 416 | |
| 417 | static const struct nfs_rw_ops nfs_rw_read_ops = { |
Anna Schumaker | a4cdda5 | 2014-05-06 09:12:31 -0400 | [diff] [blame] | 418 | .rw_mode = FMODE_READ, |
Anna Schumaker | 4a0de55 | 2014-05-06 09:12:30 -0400 | [diff] [blame] | 419 | .rw_alloc_header = nfs_readhdr_alloc, |
| 420 | .rw_free_header = nfs_readhdr_free, |
Anna Schumaker | 0eecb21 | 2014-05-06 09:12:32 -0400 | [diff] [blame] | 421 | .rw_done = nfs_readpage_done, |
| 422 | .rw_result = nfs_readpage_result, |
Anna Schumaker | 1ed26f3 | 2014-05-06 09:12:37 -0400 | [diff] [blame] | 423 | .rw_initiate = nfs_initiate_read, |
Anna Schumaker | 4a0de55 | 2014-05-06 09:12:30 -0400 | [diff] [blame] | 424 | }; |