blob: 2f093ed16980016cff7d3ece166b23d99de2e790 [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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/pagemap.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040028#include <linux/aio.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090029#include <linux/gfp.h>
Trond Myklebustb608b282010-07-30 15:31:54 -040030#include <linux/swap.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"
David Howells545db452009-04-03 16:42:44 +010038#include "fscache.h"
Benny Halevye5e94012010-10-20 00:18:01 -040039#include "pnfs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070040
41#define NFSDBG_FACILITY NFSDBG_FILE
42
43static int nfs_file_open(struct inode *, struct file *);
44static int nfs_file_release(struct inode *, struct file *);
Trond Myklebust980802e2005-06-13 11:14:01 -040045static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046static int nfs_file_mmap(struct file *, struct vm_area_struct *);
Jens Axboef0930ff2007-06-01 11:51:43 +020047static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos,
48 struct pipe_inode_info *pipe,
49 size_t count, unsigned int flags);
Badari Pulavarty027445c2006-09-30 23:28:46 -070050static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov,
51 unsigned long nr_segs, loff_t pos);
Suresh Jayaramanbf40d342009-06-17 18:02:09 -070052static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe,
53 struct file *filp, loff_t *ppos,
54 size_t count, unsigned int flags);
Badari Pulavarty027445c2006-09-30 23:28:46 -070055static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov,
56 unsigned long nr_segs, loff_t pos);
Miklos Szeredi75e1fcc2006-06-23 02:05:12 -070057static int nfs_file_flush(struct file *, fl_owner_t id);
Christoph Hellwig7ea80852010-05-26 17:53:25 +020058static int nfs_file_fsync(struct file *, int datasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -070059static int nfs_check_flags(int flags);
60static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
61static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
J. Bruce Fields370f6592007-06-08 15:23:34 -040062static int nfs_setlease(struct file *file, long arg, struct file_lock **fl);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +040064static const struct vm_operations_struct nfs_file_vm_ops;
Trond Myklebust94387fb2007-07-22 17:09:05 -040065
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080066const struct file_operations nfs_file_operations = {
Trond Myklebust980802e2005-06-13 11:14:01 -040067 .llseek = nfs_file_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 .read = do_sync_read,
69 .write = do_sync_write,
Badari Pulavarty027445c2006-09-30 23:28:46 -070070 .aio_read = nfs_file_read,
71 .aio_write = nfs_file_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 .mmap = nfs_file_mmap,
73 .open = nfs_file_open,
74 .flush = nfs_file_flush,
75 .release = nfs_file_release,
Chuck Lever54917782008-05-27 16:29:07 -040076 .fsync = nfs_file_fsync,
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 .lock = nfs_lock,
78 .flock = nfs_flock,
Jens Axboef0930ff2007-06-01 11:51:43 +020079 .splice_read = nfs_file_splice_read,
Suresh Jayaramanbf40d342009-06-17 18:02:09 -070080 .splice_write = nfs_file_splice_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 .check_flags = nfs_check_flags,
J. Bruce Fields370f6592007-06-08 15:23:34 -040082 .setlease = nfs_setlease,
Linus Torvalds1da177e2005-04-16 15:20:36 -070083};
84
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -080085const struct inode_operations nfs_file_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 .permission = nfs_permission,
87 .getattr = nfs_getattr,
88 .setattr = nfs_setattr,
89};
90
Andreas Gruenbacherb7fa0552005-06-22 17:16:27 +000091#ifdef CONFIG_NFS_V3
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -080092const struct inode_operations nfs3_file_inode_operations = {
Andreas Gruenbacherb7fa0552005-06-22 17:16:27 +000093 .permission = nfs_permission,
94 .getattr = nfs_getattr,
95 .setattr = nfs_setattr,
96 .listxattr = nfs3_listxattr,
97 .getxattr = nfs3_getxattr,
98 .setxattr = nfs3_setxattr,
99 .removexattr = nfs3_removexattr,
100};
101#endif /* CONFIG_NFS_v3 */
102
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103/* Hack for future NFS swap support */
104#ifndef IS_SWAPFILE
105# define IS_SWAPFILE(inode) (0)
106#endif
107
108static int nfs_check_flags(int flags)
109{
110 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
111 return -EINVAL;
112
113 return 0;
114}
115
116/*
117 * Open file
118 */
119static int
120nfs_file_open(struct inode *inode, struct file *filp)
121{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 int res;
123
Chuck Lever6da24bc2008-06-11 17:55:58 -0400124 dprintk("NFS: open file(%s/%s)\n",
Chuck Levercc0dd2d2008-06-11 17:55:42 -0400125 filp->f_path.dentry->d_parent->d_name.name,
126 filp->f_path.dentry->d_name.name);
127
Chuck Leverc2459dc2010-02-01 14:17:14 -0500128 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 res = nfs_check_flags(filp->f_flags);
130 if (res)
131 return res;
132
Trond Myklebust46cb6502008-06-11 16:32:46 -0400133 res = nfs_open(inode, filp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 return res;
135}
136
137static int
138nfs_file_release(struct inode *inode, struct file *filp)
139{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400140 struct dentry *dentry = filp->f_path.dentry;
141
142 dprintk("NFS: release(%s/%s)\n",
143 dentry->d_parent->d_name.name,
144 dentry->d_name.name);
145
Chuck Lever91d5b472006-03-20 13:44:14 -0500146 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
Trond Myklebust46cb6502008-06-11 16:32:46 -0400147 return nfs_release(inode, filp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148}
149
Trond Myklebust980802e2005-06-13 11:14:01 -0400150/**
151 * nfs_revalidate_size - Revalidate the file size
152 * @inode - pointer to inode struct
153 * @file - pointer to struct file
154 *
155 * Revalidates the file length. This is basically a wrapper around
156 * nfs_revalidate_inode() that takes into account the fact that we may
157 * have cached writes (in which case we don't care about the server's
158 * idea of what the file length is), or O_DIRECT (in which case we
159 * shouldn't trust the cache).
160 */
161static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
162{
163 struct nfs_server *server = NFS_SERVER(inode);
164 struct nfs_inode *nfsi = NFS_I(inode);
165
Trond Myklebustd7cf8dd2010-04-16 16:42:46 -0400166 if (nfs_have_delegated_attributes(inode))
167 goto out_noreval;
168
Trond Myklebust980802e2005-06-13 11:14:01 -0400169 if (filp->f_flags & O_DIRECT)
170 goto force_reval;
Trond Myklebustd7cf8dd2010-04-16 16:42:46 -0400171 if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
172 goto force_reval;
173 if (nfs_attribute_timeout(inode))
174 goto force_reval;
175out_noreval:
176 return 0;
Trond Myklebust980802e2005-06-13 11:14:01 -0400177force_reval:
178 return __nfs_revalidate_inode(server, inode);
179}
180
181static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
182{
Andi Kleen9465efc2008-06-27 11:05:24 +0200183 loff_t loff;
Trond Myklebuste89e8962008-07-15 18:34:16 -0400184
Chuck Lever6da24bc2008-06-11 17:55:58 -0400185 dprintk("NFS: llseek file(%s/%s, %lld, %d)\n",
Chuck Leverb84e06c2008-06-11 17:55:34 -0400186 filp->f_path.dentry->d_parent->d_name.name,
187 filp->f_path.dentry->d_name.name,
188 offset, origin);
189
Trond Myklebust980802e2005-06-13 11:14:01 -0400190 /* origin == SEEK_END => we must revalidate the cached file length */
Josef 'Jeff' Sipekaec5e172006-09-16 21:09:32 -0400191 if (origin == SEEK_END) {
Trond Myklebust980802e2005-06-13 11:14:01 -0400192 struct inode *inode = filp->f_mapping->host;
Trond Myklebustd5e66342008-09-23 17:28:35 -0400193
Trond Myklebust980802e2005-06-13 11:14:01 -0400194 int retval = nfs_revalidate_file_size(inode, filp);
195 if (retval < 0)
196 return (loff_t)retval;
Trond Myklebustd5e66342008-09-23 17:28:35 -0400197
198 spin_lock(&inode->i_lock);
199 loff = generic_file_llseek_unlocked(filp, offset, origin);
200 spin_unlock(&inode->i_lock);
201 } else
202 loff = generic_file_llseek_unlocked(filp, offset, origin);
Andi Kleen9465efc2008-06-27 11:05:24 +0200203 return loff;
Trond Myklebust980802e2005-06-13 11:14:01 -0400204}
205
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206/*
207 * Flush all dirty pages, and check for write errors.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 */
209static int
Miklos Szeredi75e1fcc2006-06-23 02:05:12 -0700210nfs_file_flush(struct file *file, fl_owner_t id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400212 struct dentry *dentry = file->f_path.dentry;
213 struct inode *inode = dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
Chuck Lever6da24bc2008-06-11 17:55:58 -0400215 dprintk("NFS: flush(%s/%s)\n",
216 dentry->d_parent->d_name.name,
217 dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218
Chuck Leverc2459dc2010-02-01 14:17:14 -0500219 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 if ((file->f_mode & FMODE_WRITE) == 0)
221 return 0;
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400222
Trond Myklebust7fe5c392009-03-19 15:35:50 -0400223 /* Flush writes to the server and return any errors */
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400224 return vfs_fsync(file, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225}
226
227static ssize_t
Badari Pulavarty027445c2006-09-30 23:28:46 -0700228nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
229 unsigned long nr_segs, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800231 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 struct inode * inode = dentry->d_inode;
233 ssize_t result;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700234 size_t count = iov_length(iov, nr_segs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 if (iocb->ki_filp->f_flags & O_DIRECT)
Badari Pulavarty027445c2006-09-30 23:28:46 -0700237 return nfs_file_direct_read(iocb, iov, nr_segs, pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238
Chuck Lever6da24bc2008-06-11 17:55:58 -0400239 dprintk("NFS: read(%s/%s, %lu@%lu)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 dentry->d_parent->d_name.name, dentry->d_name.name,
241 (unsigned long) count, (unsigned long) pos);
242
Trond Myklebust44b11872006-05-25 01:40:59 -0400243 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
Chuck Lever4184dcf2010-02-01 14:17:23 -0500244 if (!result) {
Badari Pulavarty027445c2006-09-30 23:28:46 -0700245 result = generic_file_aio_read(iocb, iov, nr_segs, pos);
Chuck Lever4184dcf2010-02-01 14:17:23 -0500246 if (result > 0)
247 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result);
248 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 return result;
250}
251
252static ssize_t
Jens Axboef0930ff2007-06-01 11:51:43 +0200253nfs_file_splice_read(struct file *filp, loff_t *ppos,
254 struct pipe_inode_info *pipe, size_t count,
255 unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800257 struct dentry *dentry = filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 struct inode *inode = dentry->d_inode;
259 ssize_t res;
260
Chuck Lever6da24bc2008-06-11 17:55:58 -0400261 dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 dentry->d_parent->d_name.name, dentry->d_name.name,
263 (unsigned long) count, (unsigned long long) *ppos);
264
Trond Myklebust44b11872006-05-25 01:40:59 -0400265 res = nfs_revalidate_mapping(inode, filp->f_mapping);
Chuck Leveraa2f1ef2010-02-01 14:17:32 -0500266 if (!res) {
Jens Axboef0930ff2007-06-01 11:51:43 +0200267 res = generic_file_splice_read(filp, ppos, pipe, count, flags);
Chuck Leveraa2f1ef2010-02-01 14:17:32 -0500268 if (res > 0)
269 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res);
270 }
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
Chuck Lever6da24bc2008-06-11 17:55:58 -0400281 dprintk("NFS: mmap(%s/%s)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 dentry->d_parent->d_name.name, dentry->d_name.name);
283
Trond Myklebuste1ebfd32009-03-11 14:37:54 -0400284 /* Note: generic_file_mmap() returns ENOSYS on nommu systems
285 * so we call that before revalidating the mapping
286 */
287 status = generic_file_mmap(file, vma);
Trond Myklebust94387fb2007-07-22 17:09:05 -0400288 if (!status) {
289 vma->vm_ops = &nfs_file_vm_ops;
Trond Myklebuste1ebfd32009-03-11 14:37:54 -0400290 status = nfs_revalidate_mapping(inode, file->f_mapping);
Trond Myklebust94387fb2007-07-22 17:09:05 -0400291 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 return status;
293}
294
295/*
296 * Flush any dirty pages for this process, and check for write errors.
297 * The return status from this call provides a reliable indication of
298 * whether any write errors occurred for this process.
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400299 *
300 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
301 * disk, but it retrieves and clears ctx->error after synching, despite
302 * the two being set at the same time in nfs_context_set_write_error().
303 * This is because the former is used to notify the _next_ call to
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300304 * nfs_file_write() that a write error occurred, and hence cause it to
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400305 * fall back to doing a synchronous write.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 */
307static int
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200308nfs_file_fsync(struct file *file, int datasync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309{
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200310 struct dentry *dentry = file->f_path.dentry;
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400311 struct nfs_open_context *ctx = nfs_file_open_context(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 struct inode *inode = dentry->d_inode;
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400313 int have_error, status;
314 int ret = 0;
315
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316
Chuck Lever6da24bc2008-06-11 17:55:58 -0400317 dprintk("NFS: fsync file(%s/%s) datasync %d\n",
Chuck Lever54917782008-05-27 16:29:07 -0400318 dentry->d_parent->d_name.name, dentry->d_name.name,
319 datasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320
Chuck Lever91d5b472006-03-20 13:44:14 -0500321 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400322 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
323 status = nfs_commit_inode(inode, FLUSH_SYNC);
324 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
325 if (have_error)
326 ret = xchg(&ctx->error, 0);
J. R. Okajima07020992010-08-11 13:10:16 -0400327 if (!ret && status < 0)
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400328 ret = status;
Andy Adamson863a3c62011-03-23 13:27:54 +0000329 if (!ret && !datasync)
330 /* application has asked for meta-data sync */
Andy Adamsonef311532011-03-12 02:58:10 -0500331 ret = pnfs_layoutcommit_inode(inode, true);
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400332 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333}
334
335/*
Peter Staubach38c73042009-08-10 08:54:16 -0400336 * Decide whether a read/modify/write cycle may be more efficient
337 * then a modify/write/read cycle when writing to a page in the
338 * page cache.
339 *
340 * The modify/write/read cycle may occur if a page is read before
341 * being completely filled by the writer. In this situation, the
342 * page must be completely written to stable storage on the server
343 * before it can be refilled by reading in the page from the server.
344 * This can lead to expensive, small, FILE_SYNC mode writes being
345 * done.
346 *
347 * It may be more efficient to read the page first if the file is
348 * open for reading in addition to writing, the page is not marked
349 * as Uptodate, it is not dirty or waiting to be committed,
350 * indicating that it was previously allocated and then modified,
351 * that there were valid bytes of data in that range of the file,
352 * and that the new data won't completely replace the old data in
353 * that range of the file.
354 */
355static int nfs_want_read_modify_write(struct file *file, struct page *page,
356 loff_t pos, unsigned len)
357{
358 unsigned int pglen = nfs_page_length(page);
359 unsigned int offset = pos & (PAGE_CACHE_SIZE - 1);
360 unsigned int end = offset + len;
361
362 if ((file->f_mode & FMODE_READ) && /* open for read? */
363 !PageUptodate(page) && /* Uptodate? */
364 !PagePrivate(page) && /* i/o request already? */
365 pglen && /* valid bytes of file? */
366 (end < pglen || offset)) /* replace all valid bytes? */
367 return 1;
368 return 0;
369}
370
371/*
Nick Piggin4899f9c2007-10-16 01:25:16 -0700372 * This does the "real" work of the write. We must allocate and lock the
373 * page to be sent back to the generic routine, which then copies the
374 * data from user space.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 *
376 * If the writer ends up delaying the write, the writer needs to
377 * increment the page use counts until he is done with the page.
378 */
Nick Piggin4899f9c2007-10-16 01:25:16 -0700379static int nfs_write_begin(struct file *file, struct address_space *mapping,
380 loff_t pos, unsigned len, unsigned flags,
381 struct page **pagep, void **fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382{
Nick Piggin4899f9c2007-10-16 01:25:16 -0700383 int ret;
Peter Staubach38c73042009-08-10 08:54:16 -0400384 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
Nick Piggin4899f9c2007-10-16 01:25:16 -0700385 struct page *page;
Peter Staubach38c73042009-08-10 08:54:16 -0400386 int once_thru = 0;
Nick Piggin4899f9c2007-10-16 01:25:16 -0700387
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400388 dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n",
389 file->f_path.dentry->d_parent->d_name.name,
390 file->f_path.dentry->d_name.name,
391 mapping->host->i_ino, len, (long long) pos);
392
Peter Staubach38c73042009-08-10 08:54:16 -0400393start:
Trond Myklebust72cb77f2009-03-11 14:10:30 -0400394 /*
395 * Prevent starvation issues if someone is doing a consistency
396 * sync-to-disk
397 */
398 ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING,
399 nfs_wait_bit_killable, TASK_KILLABLE);
400 if (ret)
401 return ret;
402
Nick Piggin54566b22009-01-04 12:00:53 -0800403 page = grab_cache_page_write_begin(mapping, index, flags);
Nick Piggin4899f9c2007-10-16 01:25:16 -0700404 if (!page)
405 return -ENOMEM;
406 *pagep = page;
407
408 ret = nfs_flush_incompatible(file, page);
409 if (ret) {
410 unlock_page(page);
411 page_cache_release(page);
Peter Staubach38c73042009-08-10 08:54:16 -0400412 } else if (!once_thru &&
413 nfs_want_read_modify_write(file, page, pos, len)) {
414 once_thru = 1;
415 ret = nfs_readpage(file, page);
416 page_cache_release(page);
417 if (!ret)
418 goto start;
Nick Piggin4899f9c2007-10-16 01:25:16 -0700419 }
420 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421}
422
Nick Piggin4899f9c2007-10-16 01:25:16 -0700423static int nfs_write_end(struct file *file, struct address_space *mapping,
424 loff_t pos, unsigned len, unsigned copied,
425 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426{
Nick Piggin4899f9c2007-10-16 01:25:16 -0700427 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
428 int status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400430 dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n",
431 file->f_path.dentry->d_parent->d_name.name,
432 file->f_path.dentry->d_name.name,
433 mapping->host->i_ino, len, (long long) pos);
434
Trond Myklebustefc91ed2008-06-10 18:31:00 -0400435 /*
436 * Zero any uninitialised parts of the page, and then mark the page
437 * as up to date if it turns out that we're extending the file.
438 */
439 if (!PageUptodate(page)) {
440 unsigned pglen = nfs_page_length(page);
441 unsigned end = offset + len;
442
443 if (pglen == 0) {
444 zero_user_segments(page, 0, offset,
445 end, PAGE_CACHE_SIZE);
446 SetPageUptodate(page);
447 } else if (end >= pglen) {
448 zero_user_segment(page, end, PAGE_CACHE_SIZE);
449 if (offset == 0)
450 SetPageUptodate(page);
451 } else
452 zero_user_segment(page, pglen, PAGE_CACHE_SIZE);
453 }
454
Nick Piggin4899f9c2007-10-16 01:25:16 -0700455 status = nfs_updatepage(file, page, offset, copied);
Nick Piggin4899f9c2007-10-16 01:25:16 -0700456
457 unlock_page(page);
458 page_cache_release(page);
459
Chuck Lever3d509e52007-12-20 14:55:04 -0500460 if (status < 0)
461 return status;
462 return copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463}
464
David Howells6b9b3512009-04-03 16:42:41 +0100465/*
466 * Partially or wholly invalidate a page
467 * - Release the private state associated with a page if undergoing complete
468 * page invalidation
David Howells545db452009-04-03 16:42:44 +0100469 * - Called if either PG_private or PG_fscache is set on the page
David Howells6b9b3512009-04-03 16:42:41 +0100470 * - Caller holds page lock
471 */
NeilBrown2ff28e22006-03-26 01:37:18 -0800472static void nfs_invalidate_page(struct page *page, unsigned long offset)
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500473{
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400474 dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset);
475
Trond Myklebust1c759502006-10-09 16:18:38 -0400476 if (offset != 0)
477 return;
Trond Myklebustd2ccddf2006-05-31 01:13:38 -0400478 /* Cancel any unstarted writes on this page */
Trond Myklebust1b3b4a12007-08-28 10:29:36 -0400479 nfs_wb_page_cancel(page->mapping->host, page);
David Howells545db452009-04-03 16:42:44 +0100480
481 nfs_fscache_invalidate_page(page, page->mapping->host);
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500482}
483
David Howells6b9b3512009-04-03 16:42:41 +0100484/*
485 * Attempt to release the private state associated with a page
David Howells545db452009-04-03 16:42:44 +0100486 * - Called if either PG_private or PG_fscache is set on the page
David Howells6b9b3512009-04-03 16:42:41 +0100487 * - Caller holds page lock
488 * - Return true (may release page) or false (may not)
489 */
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500490static int nfs_release_page(struct page *page, gfp_t gfp)
491{
Trond Myklebustb608b282010-07-30 15:31:54 -0400492 struct address_space *mapping = page->mapping;
493
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400494 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
495
Trond Myklebustd812e572010-03-19 13:55:17 -0400496 /* Only do I/O if gfp is a superset of GFP_KERNEL */
Trond Myklebustb608b282010-07-30 15:31:54 -0400497 if (mapping && (gfp & GFP_KERNEL) == GFP_KERNEL) {
498 int how = FLUSH_SYNC;
499
500 /* Don't let kswapd deadlock waiting for OOM RPC calls */
501 if (current_is_kswapd())
502 how = 0;
503 nfs_commit_inode(mapping->host, how);
504 }
Trond Myklebuste3db7692007-01-10 23:15:39 -0800505 /* If PagePrivate() is set, then the page is not freeable */
David Howells545db452009-04-03 16:42:44 +0100506 if (PagePrivate(page))
507 return 0;
508 return nfs_fscache_release_page(page, gfp);
Trond Myklebuste3db7692007-01-10 23:15:39 -0800509}
510
David Howells6b9b3512009-04-03 16:42:41 +0100511/*
512 * Attempt to clear the private state associated with a page when an error
513 * occurs that requires the cached contents of an inode to be written back or
514 * destroyed
David Howells545db452009-04-03 16:42:44 +0100515 * - Called if either PG_private or fscache is set on the page
David Howells6b9b3512009-04-03 16:42:41 +0100516 * - Caller holds page lock
517 * - Return 0 if successful, -error otherwise
518 */
Trond Myklebuste3db7692007-01-10 23:15:39 -0800519static int nfs_launder_page(struct page *page)
520{
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400521 struct inode *inode = page->mapping->host;
David Howells545db452009-04-03 16:42:44 +0100522 struct nfs_inode *nfsi = NFS_I(inode);
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400523
524 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
525 inode->i_ino, (long long)page_offset(page));
526
David Howells545db452009-04-03 16:42:44 +0100527 nfs_fscache_wait_on_page_write(nfsi, page);
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400528 return nfs_wb_page(inode, page);
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500529}
530
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700531const struct address_space_operations nfs_file_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532 .readpage = nfs_readpage,
533 .readpages = nfs_readpages,
Trond Myklebust9cccef92007-07-22 17:09:05 -0400534 .set_page_dirty = __set_page_dirty_nobuffers,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 .writepage = nfs_writepage,
536 .writepages = nfs_writepages,
Nick Piggin4899f9c2007-10-16 01:25:16 -0700537 .write_begin = nfs_write_begin,
538 .write_end = nfs_write_end,
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500539 .invalidatepage = nfs_invalidate_page,
540 .releasepage = nfs_release_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 .direct_IO = nfs_direct_IO,
Trond Myklebust074cc1d2009-08-10 08:54:13 -0400542 .migratepage = nfs_migrate_page,
Trond Myklebuste3db7692007-01-10 23:15:39 -0800543 .launder_page = nfs_launder_page,
Andi Kleenf590f332009-09-16 11:50:17 +0200544 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545};
546
David Howells6b9b3512009-04-03 16:42:41 +0100547/*
548 * Notification that a PTE pointing to an NFS page is about to be made
549 * writable, implying that someone is about to modify the page through a
550 * shared-writable mapping
551 */
Nick Pigginc2ec1752009-03-31 15:23:21 -0700552static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
Trond Myklebust94387fb2007-07-22 17:09:05 -0400553{
Nick Pigginc2ec1752009-03-31 15:23:21 -0700554 struct page *page = vmf->page;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400555 struct file *filp = vma->vm_file;
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400556 struct dentry *dentry = filp->f_path.dentry;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400557 unsigned pagelen;
Trond Myklebustbc4866b2010-10-04 17:59:08 -0400558 int ret = VM_FAULT_NOPAGE;
Nick Piggin4899f9c2007-10-16 01:25:16 -0700559 struct address_space *mapping;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400560
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400561 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n",
562 dentry->d_parent->d_name.name, dentry->d_name.name,
563 filp->f_mapping->host->i_ino,
564 (long long)page_offset(page));
565
David Howells545db452009-04-03 16:42:44 +0100566 /* make sure the cache has finished storing the page */
567 nfs_fscache_wait_on_page_write(NFS_I(dentry->d_inode), page);
568
Trond Myklebust94387fb2007-07-22 17:09:05 -0400569 lock_page(page);
Nick Piggin4899f9c2007-10-16 01:25:16 -0700570 mapping = page->mapping;
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400571 if (mapping != dentry->d_inode->i_mapping)
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500572 goto out_unlock;
573
Trond Myklebust94387fb2007-07-22 17:09:05 -0400574 pagelen = nfs_page_length(page);
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500575 if (pagelen == 0)
576 goto out_unlock;
577
Trond Myklebustbc4866b2010-10-04 17:59:08 -0400578 ret = VM_FAULT_LOCKED;
579 if (nfs_flush_incompatible(filp, page) == 0 &&
580 nfs_updatepage(filp, page, 0, pagelen) == 0)
581 goto out;
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500582
Trond Myklebustbc4866b2010-10-04 17:59:08 -0400583 ret = VM_FAULT_SIGBUS;
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500584out_unlock:
Trond Myklebust94387fb2007-07-22 17:09:05 -0400585 unlock_page(page);
Trond Myklebustbc4866b2010-10-04 17:59:08 -0400586out:
587 return ret;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400588}
589
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +0400590static const struct vm_operations_struct nfs_file_vm_ops = {
Trond Myklebust94387fb2007-07-22 17:09:05 -0400591 .fault = filemap_fault,
592 .page_mkwrite = nfs_vm_page_mkwrite,
593};
594
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400595static int nfs_need_sync_write(struct file *filp, struct inode *inode)
596{
597 struct nfs_open_context *ctx;
598
Christoph Hellwig6b2f3d12009-10-27 11:05:28 +0100599 if (IS_SYNC(inode) || (filp->f_flags & O_DSYNC))
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400600 return 1;
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400601 ctx = nfs_file_open_context(filp);
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400602 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags))
603 return 1;
604 return 0;
605}
606
Badari Pulavarty027445c2006-09-30 23:28:46 -0700607static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
608 unsigned long nr_segs, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800610 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 struct inode * inode = dentry->d_inode;
Chuck Lever7e381172010-02-01 14:17:41 -0500612 unsigned long written = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 ssize_t result;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700614 size_t count = iov_length(iov, nr_segs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 if (iocb->ki_filp->f_flags & O_DIRECT)
Badari Pulavarty027445c2006-09-30 23:28:46 -0700617 return nfs_file_direct_write(iocb, iov, nr_segs, pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618
Chuck Lever6da24bc2008-06-11 17:55:58 -0400619 dprintk("NFS: write(%s/%s, %lu@%Ld)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620 dentry->d_parent->d_name.name, dentry->d_name.name,
Chuck Lever6da24bc2008-06-11 17:55:58 -0400621 (unsigned long) count, (long long) pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622
623 result = -EBUSY;
624 if (IS_SWAPFILE(inode))
625 goto out_swapfile;
Trond Myklebust7d52e862005-06-22 17:16:30 +0000626 /*
627 * O_APPEND implies that we must revalidate the file length.
628 */
629 if (iocb->ki_filp->f_flags & O_APPEND) {
630 result = nfs_revalidate_file_size(inode, iocb->ki_filp);
631 if (result)
632 goto out;
Trond Myklebustfe51bee2005-06-22 17:16:30 +0000633 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634
635 result = count;
636 if (!count)
637 goto out;
638
Badari Pulavarty027445c2006-09-30 23:28:46 -0700639 result = generic_file_aio_write(iocb, iov, nr_segs, pos);
Chuck Lever7e381172010-02-01 14:17:41 -0500640 if (result > 0)
641 written = result;
642
Christoph Hellwig6b2f3d12009-10-27 11:05:28 +0100643 /* Return error values for O_DSYNC and IS_SYNC() */
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400644 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) {
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400645 int err = vfs_fsync(iocb->ki_filp, 0);
Trond Myklebust200baa22006-12-05 00:35:40 -0500646 if (err < 0)
647 result = err;
648 }
Chuck Lever7e381172010-02-01 14:17:41 -0500649 if (result > 0)
650 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651out:
652 return result;
653
654out_swapfile:
655 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
656 goto out;
657}
658
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700659static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe,
660 struct file *filp, loff_t *ppos,
661 size_t count, unsigned int flags)
662{
663 struct dentry *dentry = filp->f_path.dentry;
664 struct inode *inode = dentry->d_inode;
Chuck Lever7e381172010-02-01 14:17:41 -0500665 unsigned long written = 0;
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700666 ssize_t ret;
667
668 dprintk("NFS splice_write(%s/%s, %lu@%llu)\n",
669 dentry->d_parent->d_name.name, dentry->d_name.name,
670 (unsigned long) count, (unsigned long long) *ppos);
671
672 /*
673 * The combination of splice and an O_APPEND destination is disallowed.
674 */
675
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700676 ret = generic_file_splice_write(pipe, filp, ppos, count, flags);
Chuck Lever7e381172010-02-01 14:17:41 -0500677 if (ret > 0)
678 written = ret;
679
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700680 if (ret >= 0 && nfs_need_sync_write(filp, inode)) {
Trond Myklebustaf7fa162010-07-31 14:29:06 -0400681 int err = vfs_fsync(filp, 0);
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700682 if (err < 0)
683 ret = err;
684 }
Chuck Lever7e381172010-02-01 14:17:41 -0500685 if (ret > 0)
686 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700687 return ret;
688}
689
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400690static int
691do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692{
693 struct inode *inode = filp->f_mapping->host;
694 int status = 0;
Sergey Vlasov21ac19d2010-11-28 21:04:05 +0000695 unsigned int saved_type = fl->fl_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696
Trond Myklebust039c4d72005-10-18 14:20:16 -0700697 /* Try local locking first */
J. Bruce Fields6d34ac12007-05-11 16:09:32 -0400698 posix_test_lock(filp, fl);
699 if (fl->fl_type != F_UNLCK) {
700 /* found a conflict */
Trond Myklebust039c4d72005-10-18 14:20:16 -0700701 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 }
Sergey Vlasov21ac19d2010-11-28 21:04:05 +0000703 fl->fl_type = saved_type;
Trond Myklebust039c4d72005-10-18 14:20:16 -0700704
705 if (nfs_have_delegation(inode, FMODE_READ))
706 goto out_noconflict;
707
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400708 if (is_local)
Trond Myklebust039c4d72005-10-18 14:20:16 -0700709 goto out_noconflict;
710
711 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
712out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 return status;
Trond Myklebust039c4d72005-10-18 14:20:16 -0700714out_noconflict:
715 fl->fl_type = F_UNLCK;
716 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717}
718
719static int do_vfs_lock(struct file *file, struct file_lock *fl)
720{
721 int res = 0;
722 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
723 case FL_POSIX:
724 res = posix_lock_file_wait(file, fl);
725 break;
726 case FL_FLOCK:
727 res = flock_lock_file_wait(file, fl);
728 break;
729 default:
730 BUG();
731 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 return res;
733}
734
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400735static int
736do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737{
738 struct inode *inode = filp->f_mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 int status;
740
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 /*
742 * Flush all pending writes before doing anything
743 * with locks..
744 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500745 nfs_sync_mapping(filp->f_mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746
747 /* NOTE: special case
748 * If we're signalled while cleaning up locks on process exit, we
749 * still need to complete the unlock.
750 */
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400751 /*
752 * Use local locking if mounted with "-onolock" or with appropriate
753 * "-olocal_lock="
754 */
755 if (!is_local)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
757 else
758 status = do_vfs_lock(filp, fl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 return status;
760}
761
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400762static int
Ricardo Labiaga6b967242010-10-12 16:30:05 -0700763is_time_granular(struct timespec *ts) {
764 return ((ts->tv_sec == 0) && (ts->tv_nsec <= 1000));
765}
766
767static int
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400768do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769{
770 struct inode *inode = filp->f_mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 int status;
772
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773 /*
774 * Flush all pending writes before doing anything
775 * with locks..
776 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500777 status = nfs_sync_mapping(filp->f_mapping);
778 if (status != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779 goto out;
780
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400781 /*
782 * Use local locking if mounted with "-onolock" or with appropriate
783 * "-olocal_lock="
784 */
785 if (!is_local)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
Trond Myklebustc4d7c402008-04-01 20:26:52 -0400787 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 status = do_vfs_lock(filp, fl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 if (status < 0)
790 goto out;
Ricardo Labiaga6b967242010-10-12 16:30:05 -0700791
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 /*
Ricardo Labiaga6b967242010-10-12 16:30:05 -0700793 * Revalidate the cache if the server has time stamps granular
794 * enough to detect subsecond changes. Otherwise, clear the
795 * cache to prevent missing any changes.
796 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 * This makes locking act as a cache coherency point.
798 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500799 nfs_sync_mapping(filp->f_mapping);
Ricardo Labiaga6b967242010-10-12 16:30:05 -0700800 if (!nfs_have_delegation(inode, FMODE_READ)) {
801 if (is_time_granular(&NFS_SERVER(inode)->time_delta))
802 __nfs_revalidate_inode(NFS_SERVER(inode), inode);
803 else
804 nfs_zap_caches(inode);
805 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807 return status;
808}
809
810/*
811 * Lock a (portion of) a file
812 */
813static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
814{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400815 struct inode *inode = filp->f_mapping->host;
Trond Myklebust21162712008-05-20 19:34:39 -0400816 int ret = -ENOLCK;
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400817 int is_local = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818
Chuck Lever6da24bc2008-06-11 17:55:58 -0400819 dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n",
820 filp->f_path.dentry->d_parent->d_name.name,
821 filp->f_path.dentry->d_name.name,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822 fl->fl_type, fl->fl_flags,
823 (long long)fl->fl_start, (long long)fl->fl_end);
Chuck Lever6da24bc2008-06-11 17:55:58 -0400824
Chuck Lever91d5b472006-03-20 13:44:14 -0500825 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826
827 /* No mandatory locks over NFS */
Pavel Emelyanovdfad9442007-10-01 14:41:15 -0700828 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
Trond Myklebust21162712008-05-20 19:34:39 -0400829 goto out_err;
830
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400831 if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FCNTL)
832 is_local = 1;
833
Trond Myklebust21162712008-05-20 19:34:39 -0400834 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
835 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
836 if (ret < 0)
837 goto out_err;
838 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839
840 if (IS_GETLK(cmd))
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400841 ret = do_getlk(filp, cmd, fl, is_local);
Trond Myklebust21162712008-05-20 19:34:39 -0400842 else if (fl->fl_type == F_UNLCK)
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400843 ret = do_unlk(filp, cmd, fl, is_local);
Trond Myklebust21162712008-05-20 19:34:39 -0400844 else
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400845 ret = do_setlk(filp, cmd, fl, is_local);
Trond Myklebust21162712008-05-20 19:34:39 -0400846out_err:
847 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848}
849
850/*
851 * Lock a (portion of) a file
852 */
853static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
854{
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400855 struct inode *inode = filp->f_mapping->host;
856 int is_local = 0;
857
Chuck Lever6da24bc2008-06-11 17:55:58 -0400858 dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n",
859 filp->f_path.dentry->d_parent->d_name.name,
860 filp->f_path.dentry->d_name.name,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 fl->fl_type, fl->fl_flags);
862
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 if (!(fl->fl_flags & FL_FLOCK))
864 return -ENOLCK;
865
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400866 if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK)
867 is_local = 1;
868
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869 /* We're simulating flock() locks using posix locks on the server */
870 fl->fl_owner = (fl_owner_t)filp;
871 fl->fl_start = 0;
872 fl->fl_end = OFFSET_MAX;
873
874 if (fl->fl_type == F_UNLCK)
Suresh Jayaraman5eebde22010-09-23 08:55:58 -0400875 return do_unlk(filp, cmd, fl, is_local);
876 return do_setlk(filp, cmd, fl, is_local);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877}
J. Bruce Fields370f6592007-06-08 15:23:34 -0400878
Chuck Lever6da24bc2008-06-11 17:55:58 -0400879/*
880 * There is no protocol support for leases, so we have no way to implement
881 * them correctly in the face of opens by other clients.
882 */
J. Bruce Fields370f6592007-06-08 15:23:34 -0400883static int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
884{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400885 dprintk("NFS: setlease(%s/%s, arg=%ld)\n",
886 file->f_path.dentry->d_parent->d_name.name,
887 file->f_path.dentry->d_name.name, arg);
J. Bruce Fields370f6592007-06-08 15:23:34 -0400888 return -EINVAL;
889}