blob: 7c73f06692b6c9e34d39f184435a6c6f9448a739 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/nfs/file.c
3 *
4 * Copyright (C) 1992 Rick Sladkey
5 *
6 * Changes Copyright (C) 1994 by Florian La Roche
7 * - Do not copy data too often around in the kernel.
8 * - In nfs_file_read the return value of kmalloc wasn't checked.
9 * - Put in a better version of read look-ahead buffering. Original idea
10 * and implementation by Wai S Kok elekokws@ee.nus.sg.
11 *
12 * Expire cache on write to a file by Wai S Kok (Oct 1994).
13 *
14 * Total rewrite of read side for new NFS buffer cache.. Linus.
15 *
16 * nfs regular file handling functions
17 */
18
19#include <linux/time.h>
20#include <linux/kernel.h>
21#include <linux/errno.h>
22#include <linux/fcntl.h>
23#include <linux/stat.h>
24#include <linux/nfs_fs.h>
25#include <linux/nfs_mount.h>
26#include <linux/mm.h>
27#include <linux/slab.h>
28#include <linux/pagemap.h>
29#include <linux/smp_lock.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040030#include <linux/aio.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#include <asm/uaccess.h>
33#include <asm/system.h>
34
35#include "delegation.h"
Trond Myklebust94387fb2007-07-22 17:09:05 -040036#include "internal.h"
Chuck Lever91d5b472006-03-20 13:44:14 -050037#include "iostat.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#define NFSDBG_FACILITY NFSDBG_FILE
40
41static int nfs_file_open(struct inode *, struct file *);
42static int nfs_file_release(struct inode *, struct file *);
Trond Myklebust980802e2005-06-13 11:14:01 -040043static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin);
Linus Torvalds1da177e2005-04-16 15:20:36 -070044static int nfs_file_mmap(struct file *, struct vm_area_struct *);
Jens Axboef0930ff2007-06-01 11:51:43 +020045static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos,
46 struct pipe_inode_info *pipe,
47 size_t count, unsigned int flags);
Badari Pulavarty027445c2006-09-30 23:28:46 -070048static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov,
49 unsigned long nr_segs, loff_t pos);
50static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov,
51 unsigned long nr_segs, loff_t pos);
Miklos Szeredi75e1fcc2006-06-23 02:05:12 -070052static int nfs_file_flush(struct file *, fl_owner_t id);
Linus Torvalds1da177e2005-04-16 15:20:36 -070053static int nfs_fsync(struct file *, struct dentry *dentry, int datasync);
54static int nfs_check_flags(int flags);
55static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
56static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
J. Bruce Fields370f6592007-06-08 15:23:34 -040057static int nfs_setlease(struct file *file, long arg, struct file_lock **fl);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
Trond Myklebust94387fb2007-07-22 17:09:05 -040059static struct vm_operations_struct nfs_file_vm_ops;
60
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080061const struct file_operations nfs_file_operations = {
Trond Myklebust980802e2005-06-13 11:14:01 -040062 .llseek = nfs_file_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 .read = do_sync_read,
64 .write = do_sync_write,
Badari Pulavarty027445c2006-09-30 23:28:46 -070065 .aio_read = nfs_file_read,
66 .aio_write = nfs_file_write,
Bryan Wu240ee832008-04-01 20:23:39 -070067#ifdef CONFIG_MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 .mmap = nfs_file_mmap,
Bryan Wu240ee832008-04-01 20:23:39 -070069#else
70 .mmap = generic_file_mmap,
71#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 .open = nfs_file_open,
73 .flush = nfs_file_flush,
74 .release = nfs_file_release,
75 .fsync = nfs_fsync,
76 .lock = nfs_lock,
77 .flock = nfs_flock,
Jens Axboef0930ff2007-06-01 11:51:43 +020078 .splice_read = nfs_file_splice_read,
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 .check_flags = nfs_check_flags,
J. Bruce Fields370f6592007-06-08 15:23:34 -040080 .setlease = nfs_setlease,
Linus Torvalds1da177e2005-04-16 15:20:36 -070081};
82
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -080083const struct inode_operations nfs_file_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 .permission = nfs_permission,
85 .getattr = nfs_getattr,
86 .setattr = nfs_setattr,
87};
88
Andreas Gruenbacherb7fa0552005-06-22 17:16:27 +000089#ifdef CONFIG_NFS_V3
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -080090const struct inode_operations nfs3_file_inode_operations = {
Andreas Gruenbacherb7fa0552005-06-22 17:16:27 +000091 .permission = nfs_permission,
92 .getattr = nfs_getattr,
93 .setattr = nfs_setattr,
94 .listxattr = nfs3_listxattr,
95 .getxattr = nfs3_getxattr,
96 .setxattr = nfs3_setxattr,
97 .removexattr = nfs3_removexattr,
98};
99#endif /* CONFIG_NFS_v3 */
100
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101/* Hack for future NFS swap support */
102#ifndef IS_SWAPFILE
103# define IS_SWAPFILE(inode) (0)
104#endif
105
106static int nfs_check_flags(int flags)
107{
108 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
109 return -EINVAL;
110
111 return 0;
112}
113
114/*
115 * Open file
116 */
117static int
118nfs_file_open(struct inode *inode, struct file *filp)
119{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 int res;
121
122 res = nfs_check_flags(filp->f_flags);
123 if (res)
124 return res;
125
Chuck Lever91d5b472006-03-20 13:44:14 -0500126 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 lock_kernel();
David Howells1f163412006-08-22 20:06:11 -0400128 res = NFS_PROTO(inode)->file_open(inode, filp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 unlock_kernel();
130 return res;
131}
132
133static int
134nfs_file_release(struct inode *inode, struct file *filp)
135{
136 /* Ensure that dirty pages are flushed out with the right creds */
137 if (filp->f_mode & FMODE_WRITE)
Trond Myklebusta49c3c72007-10-18 18:03:27 -0400138 nfs_wb_all(filp->f_path.dentry->d_inode);
Chuck Lever91d5b472006-03-20 13:44:14 -0500139 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 return NFS_PROTO(inode)->file_release(inode, filp);
141}
142
Trond Myklebust980802e2005-06-13 11:14:01 -0400143/**
144 * nfs_revalidate_size - Revalidate the file size
145 * @inode - pointer to inode struct
146 * @file - pointer to struct file
147 *
148 * Revalidates the file length. This is basically a wrapper around
149 * nfs_revalidate_inode() that takes into account the fact that we may
150 * have cached writes (in which case we don't care about the server's
151 * idea of what the file length is), or O_DIRECT (in which case we
152 * shouldn't trust the cache).
153 */
154static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
155{
156 struct nfs_server *server = NFS_SERVER(inode);
157 struct nfs_inode *nfsi = NFS_I(inode);
158
159 if (server->flags & NFS_MOUNT_NOAC)
160 goto force_reval;
161 if (filp->f_flags & O_DIRECT)
162 goto force_reval;
163 if (nfsi->npages != 0)
164 return 0;
Chuck Lever55296802005-08-18 11:24:09 -0700165 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode))
Trond Myklebustfe51beec2005-06-22 17:16:30 +0000166 return 0;
Trond Myklebust980802e2005-06-13 11:14:01 -0400167force_reval:
168 return __nfs_revalidate_inode(server, inode);
169}
170
171static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
172{
173 /* origin == SEEK_END => we must revalidate the cached file length */
Josef 'Jeff' Sipekaec5e172006-09-16 21:09:32 -0400174 if (origin == SEEK_END) {
Trond Myklebust980802e2005-06-13 11:14:01 -0400175 struct inode *inode = filp->f_mapping->host;
176 int retval = nfs_revalidate_file_size(inode, filp);
177 if (retval < 0)
178 return (loff_t)retval;
179 }
180 return remote_llseek(filp, offset, origin);
181}
182
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183/*
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400184 * Helper for nfs_file_flush() and nfs_fsync()
185 *
186 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
187 * disk, but it retrieves and clears ctx->error after synching, despite
188 * the two being set at the same time in nfs_context_set_write_error().
189 * This is because the former is used to notify the _next_ call to
190 * nfs_file_write() that a write error occured, and hence cause it to
191 * fall back to doing a synchronous write.
192 */
193static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode)
194{
195 int have_error, status;
196 int ret = 0;
197
198 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
199 status = nfs_wb_all(inode);
200 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
201 if (have_error)
202 ret = xchg(&ctx->error, 0);
203 if (!ret)
204 ret = status;
205 return ret;
206}
207
208/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 * Flush all dirty pages, and check for write errors.
210 *
211 */
212static int
Miklos Szeredi75e1fcc2006-06-23 02:05:12 -0700213nfs_file_flush(struct file *file, fl_owner_t id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214{
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400215 struct nfs_open_context *ctx = nfs_file_open_context(file);
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800216 struct inode *inode = file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 int status;
218
219 dfprintk(VFS, "nfs: flush(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
220
221 if ((file->f_mode & FMODE_WRITE) == 0)
222 return 0;
Chuck Lever91d5b472006-03-20 13:44:14 -0500223 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400224
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 /* Ensure that data+attribute caches are up to date after close() */
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400226 status = nfs_do_fsync(ctx, inode);
227 if (!status)
228 nfs_revalidate_inode(NFS_SERVER(inode), inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229 return status;
230}
231
232static ssize_t
Badari Pulavarty027445c2006-09-30 23:28:46 -0700233nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
234 unsigned long nr_segs, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800236 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 struct inode * inode = dentry->d_inode;
238 ssize_t result;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700239 size_t count = iov_length(iov, nr_segs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 if (iocb->ki_filp->f_flags & O_DIRECT)
Badari Pulavarty027445c2006-09-30 23:28:46 -0700242 return nfs_file_direct_read(iocb, iov, nr_segs, pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243
244 dfprintk(VFS, "nfs: read(%s/%s, %lu@%lu)\n",
245 dentry->d_parent->d_name.name, dentry->d_name.name,
246 (unsigned long) count, (unsigned long) pos);
247
Trond Myklebust44b11872006-05-25 01:40:59 -0400248 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
Chuck Lever91d5b472006-03-20 13:44:14 -0500249 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 if (!result)
Badari Pulavarty027445c2006-09-30 23:28:46 -0700251 result = generic_file_aio_read(iocb, iov, nr_segs, pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 return result;
253}
254
255static ssize_t
Jens Axboef0930ff2007-06-01 11:51:43 +0200256nfs_file_splice_read(struct file *filp, loff_t *ppos,
257 struct pipe_inode_info *pipe, size_t count,
258 unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800260 struct dentry *dentry = filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 struct inode *inode = dentry->d_inode;
262 ssize_t res;
263
Jens Axboef0930ff2007-06-01 11:51:43 +0200264 dfprintk(VFS, "nfs: splice_read(%s/%s, %lu@%Lu)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 dentry->d_parent->d_name.name, dentry->d_name.name,
266 (unsigned long) count, (unsigned long long) *ppos);
267
Trond Myklebust44b11872006-05-25 01:40:59 -0400268 res = nfs_revalidate_mapping(inode, filp->f_mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 if (!res)
Jens Axboef0930ff2007-06-01 11:51:43 +0200270 res = generic_file_splice_read(filp, ppos, pipe, count, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 return res;
272}
273
274static int
275nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
276{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800277 struct dentry *dentry = file->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 struct inode *inode = dentry->d_inode;
279 int status;
280
281 dfprintk(VFS, "nfs: mmap(%s/%s)\n",
282 dentry->d_parent->d_name.name, dentry->d_name.name);
283
Trond Myklebust44b11872006-05-25 01:40:59 -0400284 status = nfs_revalidate_mapping(inode, file->f_mapping);
Trond Myklebust94387fb2007-07-22 17:09:05 -0400285 if (!status) {
286 vma->vm_ops = &nfs_file_vm_ops;
287 vma->vm_flags |= VM_CAN_NONLINEAR;
288 file_accessed(file);
289 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 return status;
291}
292
293/*
294 * Flush any dirty pages for this process, and check for write errors.
295 * The return status from this call provides a reliable indication of
296 * whether any write errors occurred for this process.
297 */
298static int
299nfs_fsync(struct file *file, struct dentry *dentry, int datasync)
300{
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400301 struct nfs_open_context *ctx = nfs_file_open_context(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 struct inode *inode = dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303
304 dfprintk(VFS, "nfs: fsync(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
305
Chuck Lever91d5b472006-03-20 13:44:14 -0500306 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400307 return nfs_do_fsync(ctx, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308}
309
310/*
Nick Piggin4899f9c2007-10-16 01:25:16 -0700311 * This does the "real" work of the write. We must allocate and lock the
312 * page to be sent back to the generic routine, which then copies the
313 * data from user space.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 *
315 * If the writer ends up delaying the write, the writer needs to
316 * increment the page use counts until he is done with the page.
317 */
Nick Piggin4899f9c2007-10-16 01:25:16 -0700318static int nfs_write_begin(struct file *file, struct address_space *mapping,
319 loff_t pos, unsigned len, unsigned flags,
320 struct page **pagep, void **fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321{
Nick Piggin4899f9c2007-10-16 01:25:16 -0700322 int ret;
323 pgoff_t index;
324 struct page *page;
325 index = pos >> PAGE_CACHE_SHIFT;
326
327 page = __grab_cache_page(mapping, index);
328 if (!page)
329 return -ENOMEM;
330 *pagep = page;
331
332 ret = nfs_flush_incompatible(file, page);
333 if (ret) {
334 unlock_page(page);
335 page_cache_release(page);
336 }
337 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338}
339
Nick Piggin4899f9c2007-10-16 01:25:16 -0700340static int nfs_write_end(struct file *file, struct address_space *mapping,
341 loff_t pos, unsigned len, unsigned copied,
342 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343{
Nick Piggin4899f9c2007-10-16 01:25:16 -0700344 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
345 int status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346
347 lock_kernel();
Nick Piggin4899f9c2007-10-16 01:25:16 -0700348 status = nfs_updatepage(file, page, offset, copied);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349 unlock_kernel();
Nick Piggin4899f9c2007-10-16 01:25:16 -0700350
351 unlock_page(page);
352 page_cache_release(page);
353
Chuck Lever3d509e52007-12-20 14:55:04 -0500354 if (status < 0)
355 return status;
356 return copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357}
358
NeilBrown2ff28e22006-03-26 01:37:18 -0800359static void nfs_invalidate_page(struct page *page, unsigned long offset)
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500360{
Trond Myklebust1c759502006-10-09 16:18:38 -0400361 if (offset != 0)
362 return;
Trond Myklebustd2ccddf2006-05-31 01:13:38 -0400363 /* Cancel any unstarted writes on this page */
Trond Myklebust1b3b4a12007-08-28 10:29:36 -0400364 nfs_wb_page_cancel(page->mapping->host, page);
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500365}
366
367static int nfs_release_page(struct page *page, gfp_t gfp)
368{
Trond Myklebuste3db7692007-01-10 23:15:39 -0800369 /* If PagePrivate() is set, then the page is not freeable */
370 return 0;
371}
372
373static int nfs_launder_page(struct page *page)
374{
375 return nfs_wb_page(page->mapping->host, page);
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500376}
377
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700378const struct address_space_operations nfs_file_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 .readpage = nfs_readpage,
380 .readpages = nfs_readpages,
Trond Myklebust9cccef92007-07-22 17:09:05 -0400381 .set_page_dirty = __set_page_dirty_nobuffers,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 .writepage = nfs_writepage,
383 .writepages = nfs_writepages,
Nick Piggin4899f9c2007-10-16 01:25:16 -0700384 .write_begin = nfs_write_begin,
385 .write_end = nfs_write_end,
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500386 .invalidatepage = nfs_invalidate_page,
387 .releasepage = nfs_release_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 .direct_IO = nfs_direct_IO,
Trond Myklebuste3db7692007-01-10 23:15:39 -0800389 .launder_page = nfs_launder_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390};
391
Trond Myklebust94387fb2007-07-22 17:09:05 -0400392static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
393{
394 struct file *filp = vma->vm_file;
395 unsigned pagelen;
396 int ret = -EINVAL;
Nick Piggin4899f9c2007-10-16 01:25:16 -0700397 struct address_space *mapping;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400398
399 lock_page(page);
Nick Piggin4899f9c2007-10-16 01:25:16 -0700400 mapping = page->mapping;
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500401 if (mapping != vma->vm_file->f_path.dentry->d_inode->i_mapping)
402 goto out_unlock;
403
404 ret = 0;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400405 pagelen = nfs_page_length(page);
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500406 if (pagelen == 0)
407 goto out_unlock;
408
409 ret = nfs_flush_incompatible(filp, page);
410 if (ret != 0)
411 goto out_unlock;
412
413 ret = nfs_updatepage(filp, page, 0, pagelen);
414 if (ret == 0)
415 ret = pagelen;
416out_unlock:
Trond Myklebust94387fb2007-07-22 17:09:05 -0400417 unlock_page(page);
418 return ret;
419}
420
421static struct vm_operations_struct nfs_file_vm_ops = {
422 .fault = filemap_fault,
423 .page_mkwrite = nfs_vm_page_mkwrite,
424};
425
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400426static int nfs_need_sync_write(struct file *filp, struct inode *inode)
427{
428 struct nfs_open_context *ctx;
429
430 if (IS_SYNC(inode) || (filp->f_flags & O_SYNC))
431 return 1;
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400432 ctx = nfs_file_open_context(filp);
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400433 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags))
434 return 1;
435 return 0;
436}
437
Badari Pulavarty027445c2006-09-30 23:28:46 -0700438static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
439 unsigned long nr_segs, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800441 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 struct inode * inode = dentry->d_inode;
443 ssize_t result;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700444 size_t count = iov_length(iov, nr_segs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 if (iocb->ki_filp->f_flags & O_DIRECT)
Badari Pulavarty027445c2006-09-30 23:28:46 -0700447 return nfs_file_direct_write(iocb, iov, nr_segs, pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
Badari Pulavarty027445c2006-09-30 23:28:46 -0700449 dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%Ld)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 dentry->d_parent->d_name.name, dentry->d_name.name,
Badari Pulavarty027445c2006-09-30 23:28:46 -0700451 inode->i_ino, (unsigned long) count, (long long) pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452
453 result = -EBUSY;
454 if (IS_SWAPFILE(inode))
455 goto out_swapfile;
Trond Myklebust7d52e862005-06-22 17:16:30 +0000456 /*
457 * O_APPEND implies that we must revalidate the file length.
458 */
459 if (iocb->ki_filp->f_flags & O_APPEND) {
460 result = nfs_revalidate_file_size(inode, iocb->ki_filp);
461 if (result)
462 goto out;
Trond Myklebustfe51beec2005-06-22 17:16:30 +0000463 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464
465 result = count;
466 if (!count)
467 goto out;
468
Chuck Lever91d5b472006-03-20 13:44:14 -0500469 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count);
Badari Pulavarty027445c2006-09-30 23:28:46 -0700470 result = generic_file_aio_write(iocb, iov, nr_segs, pos);
Trond Myklebust200baa22006-12-05 00:35:40 -0500471 /* Return error values for O_SYNC and IS_SYNC() */
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400472 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) {
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400473 int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode);
Trond Myklebust200baa22006-12-05 00:35:40 -0500474 if (err < 0)
475 result = err;
476 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477out:
478 return result;
479
480out_swapfile:
481 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
482 goto out;
483}
484
485static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
486{
487 struct inode *inode = filp->f_mapping->host;
488 int status = 0;
489
490 lock_kernel();
Trond Myklebust039c4d72005-10-18 14:20:16 -0700491 /* Try local locking first */
J. Bruce Fields6d34ac12007-05-11 16:09:32 -0400492 posix_test_lock(filp, fl);
493 if (fl->fl_type != F_UNLCK) {
494 /* found a conflict */
Trond Myklebust039c4d72005-10-18 14:20:16 -0700495 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 }
Trond Myklebust039c4d72005-10-18 14:20:16 -0700497
498 if (nfs_have_delegation(inode, FMODE_READ))
499 goto out_noconflict;
500
501 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)
502 goto out_noconflict;
503
504 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
505out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 unlock_kernel();
507 return status;
Trond Myklebust039c4d72005-10-18 14:20:16 -0700508out_noconflict:
509 fl->fl_type = F_UNLCK;
510 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511}
512
513static int do_vfs_lock(struct file *file, struct file_lock *fl)
514{
515 int res = 0;
516 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
517 case FL_POSIX:
518 res = posix_lock_file_wait(file, fl);
519 break;
520 case FL_FLOCK:
521 res = flock_lock_file_wait(file, fl);
522 break;
523 default:
524 BUG();
525 }
526 if (res < 0)
Neil Brown46bae1a2007-01-30 14:36:01 -0800527 dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager"
528 " - error %d!\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700529 __func__, res);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 return res;
531}
532
533static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
534{
535 struct inode *inode = filp->f_mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 int status;
537
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 /*
539 * Flush all pending writes before doing anything
540 * with locks..
541 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500542 nfs_sync_mapping(filp->f_mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543
544 /* NOTE: special case
545 * If we're signalled while cleaning up locks on process exit, we
546 * still need to complete the unlock.
547 */
548 lock_kernel();
549 /* Use local locking if mounted with "-onolock" */
550 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
551 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
552 else
553 status = do_vfs_lock(filp, fl);
554 unlock_kernel();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 return status;
556}
557
558static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
559{
560 struct inode *inode = filp->f_mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 int status;
562
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 /*
564 * Flush all pending writes before doing anything
565 * with locks..
566 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500567 status = nfs_sync_mapping(filp->f_mapping);
568 if (status != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 goto out;
570
571 lock_kernel();
572 /* Use local locking if mounted with "-onolock" */
Trond Myklebustc4d7c402008-04-01 20:26:52 -0400573 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
Trond Myklebustc4d7c402008-04-01 20:26:52 -0400575 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 status = do_vfs_lock(filp, fl);
577 unlock_kernel();
578 if (status < 0)
579 goto out;
580 /*
581 * Make sure we clear the cache whenever we try to get the lock.
582 * This makes locking act as a cache coherency point.
583 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500584 nfs_sync_mapping(filp->f_mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 nfs_zap_caches(inode);
586out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 return status;
588}
589
590/*
591 * Lock a (portion of) a file
592 */
593static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
594{
595 struct inode * inode = filp->f_mapping->host;
Trond Myklebust21162712008-05-20 19:34:39 -0400596 int ret = -ENOLCK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597
598 dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
599 inode->i_sb->s_id, inode->i_ino,
600 fl->fl_type, fl->fl_flags,
601 (long long)fl->fl_start, (long long)fl->fl_end);
Chuck Lever91d5b472006-03-20 13:44:14 -0500602 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603
604 /* No mandatory locks over NFS */
Pavel Emelyanovdfad9442007-10-01 14:41:15 -0700605 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
Trond Myklebust21162712008-05-20 19:34:39 -0400606 goto out_err;
607
608 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
609 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
610 if (ret < 0)
611 goto out_err;
612 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613
614 if (IS_GETLK(cmd))
Trond Myklebust21162712008-05-20 19:34:39 -0400615 ret = do_getlk(filp, cmd, fl);
616 else if (fl->fl_type == F_UNLCK)
617 ret = do_unlk(filp, cmd, fl);
618 else
619 ret = do_setlk(filp, cmd, fl);
620out_err:
621 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622}
623
624/*
625 * Lock a (portion of) a file
626 */
627static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
628{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 dprintk("NFS: nfs_flock(f=%s/%ld, t=%x, fl=%x)\n",
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800630 filp->f_path.dentry->d_inode->i_sb->s_id,
631 filp->f_path.dentry->d_inode->i_ino,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 fl->fl_type, fl->fl_flags);
633
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 /*
635 * No BSD flocks over NFS allowed.
636 * Note: we could try to fake a POSIX lock request here by
637 * using ((u32) filp | 0x80000000) or some such as the pid.
638 * Not sure whether that would be unique, though, or whether
639 * that would break in other places.
640 */
641 if (!(fl->fl_flags & FL_FLOCK))
642 return -ENOLCK;
643
644 /* We're simulating flock() locks using posix locks on the server */
645 fl->fl_owner = (fl_owner_t)filp;
646 fl->fl_start = 0;
647 fl->fl_end = OFFSET_MAX;
648
649 if (fl->fl_type == F_UNLCK)
650 return do_unlk(filp, cmd, fl);
651 return do_setlk(filp, cmd, fl);
652}
J. Bruce Fields370f6592007-06-08 15:23:34 -0400653
654static int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
655{
656 /*
657 * There is no protocol support for leases, so we have no way
658 * to implement them correctly in the face of opens by other
659 * clients.
660 */
661 return -EINVAL;
662}