blob: ae0d92736531c4da6ffaa0e8ac33a85287f2b36f [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>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040029#include <linux/aio.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030
31#include <asm/uaccess.h>
32#include <asm/system.h>
33
34#include "delegation.h"
Trond Myklebust94387fb2007-07-22 17:09:05 -040035#include "internal.h"
Chuck Lever91d5b472006-03-20 13:44:14 -050036#include "iostat.h"
David Howells545db452009-04-03 16:42:44 +010037#include "fscache.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);
Suresh Jayaramanbf40d342009-06-17 18:02:09 -070050static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe,
51 struct file *filp, loff_t *ppos,
52 size_t count, unsigned int flags);
Badari Pulavarty027445c2006-09-30 23:28:46 -070053static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov,
54 unsigned long nr_segs, loff_t pos);
Miklos Szeredi75e1fcc2006-06-23 02:05:12 -070055static int nfs_file_flush(struct file *, fl_owner_t id);
Chuck Lever54917782008-05-27 16:29:07 -040056static int nfs_file_fsync(struct file *, struct dentry *dentry, int datasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057static int nfs_check_flags(int flags);
58static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
59static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
J. Bruce Fields370f6592007-06-08 15:23:34 -040060static int nfs_setlease(struct file *file, long arg, struct file_lock **fl);
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +040062static const struct vm_operations_struct nfs_file_vm_ops;
Trond Myklebust94387fb2007-07-22 17:09:05 -040063
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080064const struct file_operations nfs_file_operations = {
Trond Myklebust980802e2005-06-13 11:14:01 -040065 .llseek = nfs_file_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 .read = do_sync_read,
67 .write = do_sync_write,
Badari Pulavarty027445c2006-09-30 23:28:46 -070068 .aio_read = nfs_file_read,
69 .aio_write = nfs_file_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 .mmap = nfs_file_mmap,
71 .open = nfs_file_open,
72 .flush = nfs_file_flush,
73 .release = nfs_file_release,
Chuck Lever54917782008-05-27 16:29:07 -040074 .fsync = nfs_file_fsync,
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 .lock = nfs_lock,
76 .flock = nfs_flock,
Jens Axboef0930ff2007-06-01 11:51:43 +020077 .splice_read = nfs_file_splice_read,
Suresh Jayaramanbf40d342009-06-17 18:02:09 -070078 .splice_write = nfs_file_splice_write,
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
Chuck Lever6da24bc2008-06-11 17:55:58 -0400122 dprintk("NFS: open file(%s/%s)\n",
Chuck Levercc0dd2d2008-06-11 17:55:42 -0400123 filp->f_path.dentry->d_parent->d_name.name,
124 filp->f_path.dentry->d_name.name);
125
Chuck Leverc2459dc2010-02-01 14:17:14 -0500126 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 res = nfs_check_flags(filp->f_flags);
128 if (res)
129 return res;
130
Trond Myklebust46cb6502008-06-11 16:32:46 -0400131 res = nfs_open(inode, filp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 return res;
133}
134
135static int
136nfs_file_release(struct inode *inode, struct file *filp)
137{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400138 struct dentry *dentry = filp->f_path.dentry;
139
140 dprintk("NFS: release(%s/%s)\n",
141 dentry->d_parent->d_name.name,
142 dentry->d_name.name);
143
Chuck Lever91d5b472006-03-20 13:44:14 -0500144 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
Trond Myklebust46cb6502008-06-11 16:32:46 -0400145 return nfs_release(inode, filp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146}
147
Trond Myklebust980802e2005-06-13 11:14:01 -0400148/**
149 * nfs_revalidate_size - Revalidate the file size
150 * @inode - pointer to inode struct
151 * @file - pointer to struct file
152 *
153 * Revalidates the file length. This is basically a wrapper around
154 * nfs_revalidate_inode() that takes into account the fact that we may
155 * have cached writes (in which case we don't care about the server's
156 * idea of what the file length is), or O_DIRECT (in which case we
157 * shouldn't trust the cache).
158 */
159static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
160{
161 struct nfs_server *server = NFS_SERVER(inode);
162 struct nfs_inode *nfsi = NFS_I(inode);
163
164 if (server->flags & NFS_MOUNT_NOAC)
165 goto force_reval;
166 if (filp->f_flags & O_DIRECT)
167 goto force_reval;
168 if (nfsi->npages != 0)
169 return 0;
Chuck Lever55296802005-08-18 11:24:09 -0700170 if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode))
Trond Myklebustfe51beec2005-06-22 17:16:30 +0000171 return 0;
Trond Myklebust980802e2005-06-13 11:14:01 -0400172force_reval:
173 return __nfs_revalidate_inode(server, inode);
174}
175
176static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
177{
Andi Kleen9465efc2008-06-27 11:05:24 +0200178 loff_t loff;
Trond Myklebuste89e8962008-07-15 18:34:16 -0400179
Chuck Lever6da24bc2008-06-11 17:55:58 -0400180 dprintk("NFS: llseek file(%s/%s, %lld, %d)\n",
Chuck Leverb84e06c2008-06-11 17:55:34 -0400181 filp->f_path.dentry->d_parent->d_name.name,
182 filp->f_path.dentry->d_name.name,
183 offset, origin);
184
Trond Myklebust980802e2005-06-13 11:14:01 -0400185 /* origin == SEEK_END => we must revalidate the cached file length */
Josef 'Jeff' Sipekaec5e172006-09-16 21:09:32 -0400186 if (origin == SEEK_END) {
Trond Myklebust980802e2005-06-13 11:14:01 -0400187 struct inode *inode = filp->f_mapping->host;
Trond Myklebustd5e66342008-09-23 17:28:35 -0400188
Trond Myklebust980802e2005-06-13 11:14:01 -0400189 int retval = nfs_revalidate_file_size(inode, filp);
190 if (retval < 0)
191 return (loff_t)retval;
Trond Myklebustd5e66342008-09-23 17:28:35 -0400192
193 spin_lock(&inode->i_lock);
194 loff = generic_file_llseek_unlocked(filp, offset, origin);
195 spin_unlock(&inode->i_lock);
196 } else
197 loff = generic_file_llseek_unlocked(filp, offset, origin);
Andi Kleen9465efc2008-06-27 11:05:24 +0200198 return loff;
Trond Myklebust980802e2005-06-13 11:14:01 -0400199}
200
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201/*
Chuck Lever54917782008-05-27 16:29:07 -0400202 * Helper for nfs_file_flush() and nfs_file_fsync()
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400203 *
204 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
205 * disk, but it retrieves and clears ctx->error after synching, despite
206 * the two being set at the same time in nfs_context_set_write_error().
207 * This is because the former is used to notify the _next_ call to
208 * nfs_file_write() that a write error occured, and hence cause it to
209 * fall back to doing a synchronous write.
210 */
211static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode)
212{
213 int have_error, status;
214 int ret = 0;
215
216 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
217 status = nfs_wb_all(inode);
218 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
219 if (have_error)
220 ret = xchg(&ctx->error, 0);
221 if (!ret)
222 ret = status;
223 return ret;
224}
225
226/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 * Flush all dirty pages, and check for write errors.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 */
229static int
Miklos Szeredi75e1fcc2006-06-23 02:05:12 -0700230nfs_file_flush(struct file *file, fl_owner_t id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231{
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400232 struct nfs_open_context *ctx = nfs_file_open_context(file);
Chuck Lever6da24bc2008-06-11 17:55:58 -0400233 struct dentry *dentry = file->f_path.dentry;
234 struct inode *inode = dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235
Chuck Lever6da24bc2008-06-11 17:55:58 -0400236 dprintk("NFS: flush(%s/%s)\n",
237 dentry->d_parent->d_name.name,
238 dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239
Chuck Leverc2459dc2010-02-01 14:17:14 -0500240 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 if ((file->f_mode & FMODE_WRITE) == 0)
242 return 0;
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400243
Trond Myklebust7fe5c392009-03-19 15:35:50 -0400244 /* Flush writes to the server and return any errors */
245 return nfs_do_fsync(ctx, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246}
247
248static ssize_t
Badari Pulavarty027445c2006-09-30 23:28:46 -0700249nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
250 unsigned long nr_segs, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800252 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 struct inode * inode = dentry->d_inode;
254 ssize_t result;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700255 size_t count = iov_length(iov, nr_segs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 if (iocb->ki_filp->f_flags & O_DIRECT)
Badari Pulavarty027445c2006-09-30 23:28:46 -0700258 return nfs_file_direct_read(iocb, iov, nr_segs, pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259
Chuck Lever6da24bc2008-06-11 17:55:58 -0400260 dprintk("NFS: read(%s/%s, %lu@%lu)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 dentry->d_parent->d_name.name, dentry->d_name.name,
262 (unsigned long) count, (unsigned long) pos);
263
Trond Myklebust44b11872006-05-25 01:40:59 -0400264 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
Chuck Lever4184dcf2010-02-01 14:17:23 -0500265 if (!result) {
Badari Pulavarty027445c2006-09-30 23:28:46 -0700266 result = generic_file_aio_read(iocb, iov, nr_segs, pos);
Chuck Lever4184dcf2010-02-01 14:17:23 -0500267 if (result > 0)
268 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result);
269 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 return result;
271}
272
273static ssize_t
Jens Axboef0930ff2007-06-01 11:51:43 +0200274nfs_file_splice_read(struct file *filp, loff_t *ppos,
275 struct pipe_inode_info *pipe, size_t count,
276 unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800278 struct dentry *dentry = filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 struct inode *inode = dentry->d_inode;
280 ssize_t res;
281
Chuck Lever6da24bc2008-06-11 17:55:58 -0400282 dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 dentry->d_parent->d_name.name, dentry->d_name.name,
284 (unsigned long) count, (unsigned long long) *ppos);
285
Trond Myklebust44b11872006-05-25 01:40:59 -0400286 res = nfs_revalidate_mapping(inode, filp->f_mapping);
Chuck Leveraa2f1ef2010-02-01 14:17:32 -0500287 if (!res) {
Jens Axboef0930ff2007-06-01 11:51:43 +0200288 res = generic_file_splice_read(filp, ppos, pipe, count, flags);
Chuck Leveraa2f1ef2010-02-01 14:17:32 -0500289 if (res > 0)
290 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res);
291 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 return res;
293}
294
295static int
296nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
297{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800298 struct dentry *dentry = file->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 struct inode *inode = dentry->d_inode;
300 int status;
301
Chuck Lever6da24bc2008-06-11 17:55:58 -0400302 dprintk("NFS: mmap(%s/%s)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 dentry->d_parent->d_name.name, dentry->d_name.name);
304
Trond Myklebuste1ebfd32009-03-11 14:37:54 -0400305 /* Note: generic_file_mmap() returns ENOSYS on nommu systems
306 * so we call that before revalidating the mapping
307 */
308 status = generic_file_mmap(file, vma);
Trond Myklebust94387fb2007-07-22 17:09:05 -0400309 if (!status) {
310 vma->vm_ops = &nfs_file_vm_ops;
Trond Myklebuste1ebfd32009-03-11 14:37:54 -0400311 status = nfs_revalidate_mapping(inode, file->f_mapping);
Trond Myklebust94387fb2007-07-22 17:09:05 -0400312 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 return status;
314}
315
316/*
317 * Flush any dirty pages for this process, and check for write errors.
318 * The return status from this call provides a reliable indication of
319 * whether any write errors occurred for this process.
320 */
321static int
Chuck Lever54917782008-05-27 16:29:07 -0400322nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323{
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400324 struct nfs_open_context *ctx = nfs_file_open_context(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 struct inode *inode = dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
Chuck Lever6da24bc2008-06-11 17:55:58 -0400327 dprintk("NFS: fsync file(%s/%s) datasync %d\n",
Chuck Lever54917782008-05-27 16:29:07 -0400328 dentry->d_parent->d_name.name, dentry->d_name.name,
329 datasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330
Chuck Lever91d5b472006-03-20 13:44:14 -0500331 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400332 return nfs_do_fsync(ctx, inode);
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{
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400492 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
493
Trond Myklebustd812e572010-03-19 13:55:17 -0400494 /* Only do I/O if gfp is a superset of GFP_KERNEL */
495 if ((gfp & GFP_KERNEL) == GFP_KERNEL)
Trond Myklebust82be9342010-01-26 15:41:53 -0500496 nfs_wb_page(page->mapping->host, page);
Trond Myklebuste3db7692007-01-10 23:15:39 -0800497 /* If PagePrivate() is set, then the page is not freeable */
David Howells545db452009-04-03 16:42:44 +0100498 if (PagePrivate(page))
499 return 0;
500 return nfs_fscache_release_page(page, gfp);
Trond Myklebuste3db7692007-01-10 23:15:39 -0800501}
502
David Howells6b9b3512009-04-03 16:42:41 +0100503/*
504 * Attempt to clear the private state associated with a page when an error
505 * occurs that requires the cached contents of an inode to be written back or
506 * destroyed
David Howells545db452009-04-03 16:42:44 +0100507 * - Called if either PG_private or fscache is set on the page
David Howells6b9b3512009-04-03 16:42:41 +0100508 * - Caller holds page lock
509 * - Return 0 if successful, -error otherwise
510 */
Trond Myklebuste3db7692007-01-10 23:15:39 -0800511static int nfs_launder_page(struct page *page)
512{
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400513 struct inode *inode = page->mapping->host;
David Howells545db452009-04-03 16:42:44 +0100514 struct nfs_inode *nfsi = NFS_I(inode);
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400515
516 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
517 inode->i_ino, (long long)page_offset(page));
518
David Howells545db452009-04-03 16:42:44 +0100519 nfs_fscache_wait_on_page_write(nfsi, page);
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400520 return nfs_wb_page(inode, page);
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500521}
522
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700523const struct address_space_operations nfs_file_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 .readpage = nfs_readpage,
525 .readpages = nfs_readpages,
Trond Myklebust9cccef92007-07-22 17:09:05 -0400526 .set_page_dirty = __set_page_dirty_nobuffers,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 .writepage = nfs_writepage,
528 .writepages = nfs_writepages,
Nick Piggin4899f9c2007-10-16 01:25:16 -0700529 .write_begin = nfs_write_begin,
530 .write_end = nfs_write_end,
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500531 .invalidatepage = nfs_invalidate_page,
532 .releasepage = nfs_release_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 .direct_IO = nfs_direct_IO,
Trond Myklebust074cc1d2009-08-10 08:54:13 -0400534 .migratepage = nfs_migrate_page,
Trond Myklebuste3db7692007-01-10 23:15:39 -0800535 .launder_page = nfs_launder_page,
Andi Kleenf590f332009-09-16 11:50:17 +0200536 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537};
538
David Howells6b9b3512009-04-03 16:42:41 +0100539/*
540 * Notification that a PTE pointing to an NFS page is about to be made
541 * writable, implying that someone is about to modify the page through a
542 * shared-writable mapping
543 */
Nick Pigginc2ec1752009-03-31 15:23:21 -0700544static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
Trond Myklebust94387fb2007-07-22 17:09:05 -0400545{
Nick Pigginc2ec1752009-03-31 15:23:21 -0700546 struct page *page = vmf->page;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400547 struct file *filp = vma->vm_file;
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400548 struct dentry *dentry = filp->f_path.dentry;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400549 unsigned pagelen;
550 int ret = -EINVAL;
Nick Piggin4899f9c2007-10-16 01:25:16 -0700551 struct address_space *mapping;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400552
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400553 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n",
554 dentry->d_parent->d_name.name, dentry->d_name.name,
555 filp->f_mapping->host->i_ino,
556 (long long)page_offset(page));
557
David Howells545db452009-04-03 16:42:44 +0100558 /* make sure the cache has finished storing the page */
559 nfs_fscache_wait_on_page_write(NFS_I(dentry->d_inode), page);
560
Trond Myklebust94387fb2007-07-22 17:09:05 -0400561 lock_page(page);
Nick Piggin4899f9c2007-10-16 01:25:16 -0700562 mapping = page->mapping;
Chuck Leverb7eaefa2008-06-11 17:55:50 -0400563 if (mapping != dentry->d_inode->i_mapping)
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500564 goto out_unlock;
565
566 ret = 0;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400567 pagelen = nfs_page_length(page);
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500568 if (pagelen == 0)
569 goto out_unlock;
570
571 ret = nfs_flush_incompatible(filp, page);
572 if (ret != 0)
573 goto out_unlock;
574
575 ret = nfs_updatepage(filp, page, 0, pagelen);
Trond Myklebust8b1f9ee2008-01-22 17:13:06 -0500576out_unlock:
Trond Myklebust7fdf5232009-04-24 17:32:22 -0400577 if (!ret)
578 return VM_FAULT_LOCKED;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400579 unlock_page(page);
Trond Myklebust7fdf5232009-04-24 17:32:22 -0400580 return VM_FAULT_SIGBUS;
Trond Myklebust94387fb2007-07-22 17:09:05 -0400581}
582
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +0400583static const struct vm_operations_struct nfs_file_vm_ops = {
Trond Myklebust94387fb2007-07-22 17:09:05 -0400584 .fault = filemap_fault,
585 .page_mkwrite = nfs_vm_page_mkwrite,
586};
587
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400588static int nfs_need_sync_write(struct file *filp, struct inode *inode)
589{
590 struct nfs_open_context *ctx;
591
Christoph Hellwig6b2f3d12009-10-27 11:05:28 +0100592 if (IS_SYNC(inode) || (filp->f_flags & O_DSYNC))
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400593 return 1;
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400594 ctx = nfs_file_open_context(filp);
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400595 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags))
596 return 1;
597 return 0;
598}
599
Badari Pulavarty027445c2006-09-30 23:28:46 -0700600static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
601 unsigned long nr_segs, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800603 struct dentry * dentry = iocb->ki_filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 struct inode * inode = dentry->d_inode;
Chuck Lever7e381172010-02-01 14:17:41 -0500605 unsigned long written = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 ssize_t result;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700607 size_t count = iov_length(iov, nr_segs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 if (iocb->ki_filp->f_flags & O_DIRECT)
Badari Pulavarty027445c2006-09-30 23:28:46 -0700610 return nfs_file_direct_write(iocb, iov, nr_segs, pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611
Chuck Lever6da24bc2008-06-11 17:55:58 -0400612 dprintk("NFS: write(%s/%s, %lu@%Ld)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 dentry->d_parent->d_name.name, dentry->d_name.name,
Chuck Lever6da24bc2008-06-11 17:55:58 -0400614 (unsigned long) count, (long long) pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615
616 result = -EBUSY;
617 if (IS_SWAPFILE(inode))
618 goto out_swapfile;
Trond Myklebust7d52e862005-06-22 17:16:30 +0000619 /*
620 * O_APPEND implies that we must revalidate the file length.
621 */
622 if (iocb->ki_filp->f_flags & O_APPEND) {
623 result = nfs_revalidate_file_size(inode, iocb->ki_filp);
624 if (result)
625 goto out;
Trond Myklebustfe51beec2005-06-22 17:16:30 +0000626 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627
628 result = count;
629 if (!count)
630 goto out;
631
Badari Pulavarty027445c2006-09-30 23:28:46 -0700632 result = generic_file_aio_write(iocb, iov, nr_segs, pos);
Chuck Lever7e381172010-02-01 14:17:41 -0500633 if (result > 0)
634 written = result;
635
Christoph Hellwig6b2f3d12009-10-27 11:05:28 +0100636 /* Return error values for O_DSYNC and IS_SYNC() */
Trond Myklebust7b159fc2007-07-25 14:09:54 -0400637 if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) {
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400638 int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode);
Trond Myklebust200baa22006-12-05 00:35:40 -0500639 if (err < 0)
640 result = err;
641 }
Chuck Lever7e381172010-02-01 14:17:41 -0500642 if (result > 0)
643 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644out:
645 return result;
646
647out_swapfile:
648 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
649 goto out;
650}
651
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700652static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe,
653 struct file *filp, loff_t *ppos,
654 size_t count, unsigned int flags)
655{
656 struct dentry *dentry = filp->f_path.dentry;
657 struct inode *inode = dentry->d_inode;
Chuck Lever7e381172010-02-01 14:17:41 -0500658 unsigned long written = 0;
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700659 ssize_t ret;
660
661 dprintk("NFS splice_write(%s/%s, %lu@%llu)\n",
662 dentry->d_parent->d_name.name, dentry->d_name.name,
663 (unsigned long) count, (unsigned long long) *ppos);
664
665 /*
666 * The combination of splice and an O_APPEND destination is disallowed.
667 */
668
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700669 ret = generic_file_splice_write(pipe, filp, ppos, count, flags);
Chuck Lever7e381172010-02-01 14:17:41 -0500670 if (ret > 0)
671 written = ret;
672
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700673 if (ret >= 0 && nfs_need_sync_write(filp, inode)) {
674 int err = nfs_do_fsync(nfs_file_open_context(filp), inode);
675 if (err < 0)
676 ret = err;
677 }
Chuck Lever7e381172010-02-01 14:17:41 -0500678 if (ret > 0)
679 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
Suresh Jayaramanbf40d342009-06-17 18:02:09 -0700680 return ret;
681}
682
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
684{
685 struct inode *inode = filp->f_mapping->host;
686 int status = 0;
687
Trond Myklebust039c4d72005-10-18 14:20:16 -0700688 /* Try local locking first */
J. Bruce Fields6d34ac12007-05-11 16:09:32 -0400689 posix_test_lock(filp, fl);
690 if (fl->fl_type != F_UNLCK) {
691 /* found a conflict */
Trond Myklebust039c4d72005-10-18 14:20:16 -0700692 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693 }
Trond Myklebust039c4d72005-10-18 14:20:16 -0700694
695 if (nfs_have_delegation(inode, FMODE_READ))
696 goto out_noconflict;
697
698 if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)
699 goto out_noconflict;
700
701 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
702out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 return status;
Trond Myklebust039c4d72005-10-18 14:20:16 -0700704out_noconflict:
705 fl->fl_type = F_UNLCK;
706 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707}
708
709static int do_vfs_lock(struct file *file, struct file_lock *fl)
710{
711 int res = 0;
712 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
713 case FL_POSIX:
714 res = posix_lock_file_wait(file, fl);
715 break;
716 case FL_FLOCK:
717 res = flock_lock_file_wait(file, fl);
718 break;
719 default:
720 BUG();
721 }
722 if (res < 0)
Neil Brown46bae1a2007-01-30 14:36:01 -0800723 dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager"
724 " - error %d!\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700725 __func__, res);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 return res;
727}
728
729static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
730{
731 struct inode *inode = filp->f_mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 int status;
733
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 /*
735 * Flush all pending writes before doing anything
736 * with locks..
737 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500738 nfs_sync_mapping(filp->f_mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739
740 /* NOTE: special case
741 * If we're signalled while cleaning up locks on process exit, we
742 * still need to complete the unlock.
743 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 /* Use local locking if mounted with "-onolock" */
745 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
746 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
747 else
748 status = do_vfs_lock(filp, fl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749 return status;
750}
751
752static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
753{
754 struct inode *inode = filp->f_mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 int status;
756
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 /*
758 * Flush all pending writes before doing anything
759 * with locks..
760 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500761 status = nfs_sync_mapping(filp->f_mapping);
762 if (status != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 goto out;
764
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 /* Use local locking if mounted with "-onolock" */
Trond Myklebustc4d7c402008-04-01 20:26:52 -0400766 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
Trond Myklebustc4d7c402008-04-01 20:26:52 -0400768 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 status = do_vfs_lock(filp, fl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 if (status < 0)
771 goto out;
772 /*
773 * Make sure we clear the cache whenever we try to get the lock.
774 * This makes locking act as a cache coherency point.
775 */
Trond Myklebust29884df2005-12-13 16:13:54 -0500776 nfs_sync_mapping(filp->f_mapping);
Trond Myklebustb5418382008-06-10 18:31:02 -0400777 if (!nfs_have_delegation(inode, FMODE_READ))
778 nfs_zap_caches(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780 return status;
781}
782
783/*
784 * Lock a (portion of) a file
785 */
786static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
787{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400788 struct inode *inode = filp->f_mapping->host;
Trond Myklebust21162712008-05-20 19:34:39 -0400789 int ret = -ENOLCK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790
Chuck Lever6da24bc2008-06-11 17:55:58 -0400791 dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n",
792 filp->f_path.dentry->d_parent->d_name.name,
793 filp->f_path.dentry->d_name.name,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 fl->fl_type, fl->fl_flags,
795 (long long)fl->fl_start, (long long)fl->fl_end);
Chuck Lever6da24bc2008-06-11 17:55:58 -0400796
Chuck Lever91d5b472006-03-20 13:44:14 -0500797 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798
799 /* No mandatory locks over NFS */
Pavel Emelyanovdfad9442007-10-01 14:41:15 -0700800 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
Trond Myklebust21162712008-05-20 19:34:39 -0400801 goto out_err;
802
803 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
804 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
805 if (ret < 0)
806 goto out_err;
807 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808
809 if (IS_GETLK(cmd))
Trond Myklebust21162712008-05-20 19:34:39 -0400810 ret = do_getlk(filp, cmd, fl);
811 else if (fl->fl_type == F_UNLCK)
812 ret = do_unlk(filp, cmd, fl);
813 else
814 ret = do_setlk(filp, cmd, fl);
815out_err:
816 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817}
818
819/*
820 * Lock a (portion of) a file
821 */
822static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
823{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400824 dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n",
825 filp->f_path.dentry->d_parent->d_name.name,
826 filp->f_path.dentry->d_name.name,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827 fl->fl_type, fl->fl_flags);
828
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829 if (!(fl->fl_flags & FL_FLOCK))
830 return -ENOLCK;
831
832 /* We're simulating flock() locks using posix locks on the server */
833 fl->fl_owner = (fl_owner_t)filp;
834 fl->fl_start = 0;
835 fl->fl_end = OFFSET_MAX;
836
837 if (fl->fl_type == F_UNLCK)
838 return do_unlk(filp, cmd, fl);
839 return do_setlk(filp, cmd, fl);
840}
J. Bruce Fields370f6592007-06-08 15:23:34 -0400841
Chuck Lever6da24bc2008-06-11 17:55:58 -0400842/*
843 * There is no protocol support for leases, so we have no way to implement
844 * them correctly in the face of opens by other clients.
845 */
J. Bruce Fields370f6592007-06-08 15:23:34 -0400846static int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
847{
Chuck Lever6da24bc2008-06-11 17:55:58 -0400848 dprintk("NFS: setlease(%s/%s, arg=%ld)\n",
849 file->f_path.dentry->d_parent->d_name.name,
850 file->f_path.dentry->d_name.name, arg);
851
J. Bruce Fields370f6592007-06-08 15:23:34 -0400852 return -EINVAL;
853}