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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/nfs/file.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/nfs/file.c')
-rw-r--r--fs/nfs/file.c484
1 files changed, 484 insertions, 0 deletions
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
new file mode 100644
index 000000000000..f06eee6dcff5
--- /dev/null
+++ b/fs/nfs/file.c
@@ -0,0 +1,484 @@
1/*
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>
30
31#include <asm/uaccess.h>
32#include <asm/system.h>
33
34#include "delegation.h"
35
36#define NFSDBG_FACILITY NFSDBG_FILE
37
38static int nfs_file_open(struct inode *, struct file *);
39static int nfs_file_release(struct inode *, struct file *);
40static int nfs_file_mmap(struct file *, struct vm_area_struct *);
41static ssize_t nfs_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
42static ssize_t nfs_file_read(struct kiocb *, char __user *, size_t, loff_t);
43static ssize_t nfs_file_write(struct kiocb *, const char __user *, size_t, loff_t);
44static int nfs_file_flush(struct file *);
45static int nfs_fsync(struct file *, struct dentry *dentry, int datasync);
46static int nfs_check_flags(int flags);
47static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
48static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
49
50struct file_operations nfs_file_operations = {
51 .llseek = remote_llseek,
52 .read = do_sync_read,
53 .write = do_sync_write,
54 .aio_read = nfs_file_read,
55 .aio_write = nfs_file_write,
56 .mmap = nfs_file_mmap,
57 .open = nfs_file_open,
58 .flush = nfs_file_flush,
59 .release = nfs_file_release,
60 .fsync = nfs_fsync,
61 .lock = nfs_lock,
62 .flock = nfs_flock,
63 .sendfile = nfs_file_sendfile,
64 .check_flags = nfs_check_flags,
65};
66
67struct inode_operations nfs_file_inode_operations = {
68 .permission = nfs_permission,
69 .getattr = nfs_getattr,
70 .setattr = nfs_setattr,
71};
72
73/* Hack for future NFS swap support */
74#ifndef IS_SWAPFILE
75# define IS_SWAPFILE(inode) (0)
76#endif
77
78static int nfs_check_flags(int flags)
79{
80 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
81 return -EINVAL;
82
83 return 0;
84}
85
86/*
87 * Open file
88 */
89static int
90nfs_file_open(struct inode *inode, struct file *filp)
91{
92 struct nfs_server *server = NFS_SERVER(inode);
93 int (*open)(struct inode *, struct file *);
94 int res;
95
96 res = nfs_check_flags(filp->f_flags);
97 if (res)
98 return res;
99
100 lock_kernel();
101 /* Do NFSv4 open() call */
102 if ((open = server->rpc_ops->file_open) != NULL)
103 res = open(inode, filp);
104 unlock_kernel();
105 return res;
106}
107
108static int
109nfs_file_release(struct inode *inode, struct file *filp)
110{
111 /* Ensure that dirty pages are flushed out with the right creds */
112 if (filp->f_mode & FMODE_WRITE)
113 filemap_fdatawrite(filp->f_mapping);
114 return NFS_PROTO(inode)->file_release(inode, filp);
115}
116
117/*
118 * Flush all dirty pages, and check for write errors.
119 *
120 */
121static int
122nfs_file_flush(struct file *file)
123{
124 struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data;
125 struct inode *inode = file->f_dentry->d_inode;
126 int status;
127
128 dfprintk(VFS, "nfs: flush(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
129
130 if ((file->f_mode & FMODE_WRITE) == 0)
131 return 0;
132 lock_kernel();
133 /* Ensure that data+attribute caches are up to date after close() */
134 status = nfs_wb_all(inode);
135 if (!status) {
136 status = ctx->error;
137 ctx->error = 0;
138 if (!status && !nfs_have_delegation(inode, FMODE_READ))
139 __nfs_revalidate_inode(NFS_SERVER(inode), inode);
140 }
141 unlock_kernel();
142 return status;
143}
144
145static ssize_t
146nfs_file_read(struct kiocb *iocb, char __user * buf, size_t count, loff_t pos)
147{
148 struct dentry * dentry = iocb->ki_filp->f_dentry;
149 struct inode * inode = dentry->d_inode;
150 ssize_t result;
151
152#ifdef CONFIG_NFS_DIRECTIO
153 if (iocb->ki_filp->f_flags & O_DIRECT)
154 return nfs_file_direct_read(iocb, buf, count, pos);
155#endif
156
157 dfprintk(VFS, "nfs: read(%s/%s, %lu@%lu)\n",
158 dentry->d_parent->d_name.name, dentry->d_name.name,
159 (unsigned long) count, (unsigned long) pos);
160
161 result = nfs_revalidate_inode(NFS_SERVER(inode), inode);
162 if (!result)
163 result = generic_file_aio_read(iocb, buf, count, pos);
164 return result;
165}
166
167static ssize_t
168nfs_file_sendfile(struct file *filp, loff_t *ppos, size_t count,
169 read_actor_t actor, void *target)
170{
171 struct dentry *dentry = filp->f_dentry;
172 struct inode *inode = dentry->d_inode;
173 ssize_t res;
174
175 dfprintk(VFS, "nfs: sendfile(%s/%s, %lu@%Lu)\n",
176 dentry->d_parent->d_name.name, dentry->d_name.name,
177 (unsigned long) count, (unsigned long long) *ppos);
178
179 res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
180 if (!res)
181 res = generic_file_sendfile(filp, ppos, count, actor, target);
182 return res;
183}
184
185static int
186nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
187{
188 struct dentry *dentry = file->f_dentry;
189 struct inode *inode = dentry->d_inode;
190 int status;
191
192 dfprintk(VFS, "nfs: mmap(%s/%s)\n",
193 dentry->d_parent->d_name.name, dentry->d_name.name);
194
195 status = nfs_revalidate_inode(NFS_SERVER(inode), inode);
196 if (!status)
197 status = generic_file_mmap(file, vma);
198 return status;
199}
200
201/*
202 * Flush any dirty pages for this process, and check for write errors.
203 * The return status from this call provides a reliable indication of
204 * whether any write errors occurred for this process.
205 */
206static int
207nfs_fsync(struct file *file, struct dentry *dentry, int datasync)
208{
209 struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data;
210 struct inode *inode = dentry->d_inode;
211 int status;
212
213 dfprintk(VFS, "nfs: fsync(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
214
215 lock_kernel();
216 status = nfs_wb_all(inode);
217 if (!status) {
218 status = ctx->error;
219 ctx->error = 0;
220 }
221 unlock_kernel();
222 return status;
223}
224
225/*
226 * This does the "real" work of the write. The generic routine has
227 * allocated the page, locked it, done all the page alignment stuff
228 * calculations etc. Now we should just copy the data from user
229 * space and write it back to the real medium..
230 *
231 * If the writer ends up delaying the write, the writer needs to
232 * increment the page use counts until he is done with the page.
233 */
234static int nfs_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to)
235{
236 return nfs_flush_incompatible(file, page);
237}
238
239static int nfs_commit_write(struct file *file, struct page *page, unsigned offset, unsigned to)
240{
241 long status;
242
243 lock_kernel();
244 status = nfs_updatepage(file, page, offset, to-offset);
245 unlock_kernel();
246 return status;
247}
248
249struct address_space_operations nfs_file_aops = {
250 .readpage = nfs_readpage,
251 .readpages = nfs_readpages,
252 .set_page_dirty = __set_page_dirty_nobuffers,
253 .writepage = nfs_writepage,
254 .writepages = nfs_writepages,
255 .prepare_write = nfs_prepare_write,
256 .commit_write = nfs_commit_write,
257#ifdef CONFIG_NFS_DIRECTIO
258 .direct_IO = nfs_direct_IO,
259#endif
260};
261
262/*
263 * Write to a file (through the page cache).
264 */
265static ssize_t
266nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos)
267{
268 struct dentry * dentry = iocb->ki_filp->f_dentry;
269 struct inode * inode = dentry->d_inode;
270 ssize_t result;
271
272#ifdef CONFIG_NFS_DIRECTIO
273 if (iocb->ki_filp->f_flags & O_DIRECT)
274 return nfs_file_direct_write(iocb, buf, count, pos);
275#endif
276
277 dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%lu)\n",
278 dentry->d_parent->d_name.name, dentry->d_name.name,
279 inode->i_ino, (unsigned long) count, (unsigned long) pos);
280
281 result = -EBUSY;
282 if (IS_SWAPFILE(inode))
283 goto out_swapfile;
284 result = nfs_revalidate_inode(NFS_SERVER(inode), inode);
285 if (result)
286 goto out;
287
288 result = count;
289 if (!count)
290 goto out;
291
292 result = generic_file_aio_write(iocb, buf, count, pos);
293out:
294 return result;
295
296out_swapfile:
297 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
298 goto out;
299}
300
301static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
302{
303 struct inode *inode = filp->f_mapping->host;
304 int status = 0;
305
306 lock_kernel();
307 /* Use local locking if mounted with "-onolock" */
308 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
309 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
310 else {
311 struct file_lock *cfl = posix_test_lock(filp, fl);
312
313 fl->fl_type = F_UNLCK;
314 if (cfl != NULL)
315 memcpy(fl, cfl, sizeof(*fl));
316 }
317 unlock_kernel();
318 return status;
319}
320
321static int do_vfs_lock(struct file *file, struct file_lock *fl)
322{
323 int res = 0;
324 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
325 case FL_POSIX:
326 res = posix_lock_file_wait(file, fl);
327 break;
328 case FL_FLOCK:
329 res = flock_lock_file_wait(file, fl);
330 break;
331 default:
332 BUG();
333 }
334 if (res < 0)
335 printk(KERN_WARNING "%s: VFS is out of sync with lock manager!\n",
336 __FUNCTION__);
337 return res;
338}
339
340static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
341{
342 struct inode *inode = filp->f_mapping->host;
343 sigset_t oldset;
344 int status;
345
346 rpc_clnt_sigmask(NFS_CLIENT(inode), &oldset);
347 /*
348 * Flush all pending writes before doing anything
349 * with locks..
350 */
351 filemap_fdatawrite(filp->f_mapping);
352 down(&inode->i_sem);
353 nfs_wb_all(inode);
354 up(&inode->i_sem);
355 filemap_fdatawait(filp->f_mapping);
356
357 /* NOTE: special case
358 * If we're signalled while cleaning up locks on process exit, we
359 * still need to complete the unlock.
360 */
361 lock_kernel();
362 /* Use local locking if mounted with "-onolock" */
363 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM))
364 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
365 else
366 status = do_vfs_lock(filp, fl);
367 unlock_kernel();
368 rpc_clnt_sigunmask(NFS_CLIENT(inode), &oldset);
369 return status;
370}
371
372static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
373{
374 struct inode *inode = filp->f_mapping->host;
375 sigset_t oldset;
376 int status;
377
378 rpc_clnt_sigmask(NFS_CLIENT(inode), &oldset);
379 /*
380 * Flush all pending writes before doing anything
381 * with locks..
382 */
383 status = filemap_fdatawrite(filp->f_mapping);
384 if (status == 0) {
385 down(&inode->i_sem);
386 status = nfs_wb_all(inode);
387 up(&inode->i_sem);
388 if (status == 0)
389 status = filemap_fdatawait(filp->f_mapping);
390 }
391 if (status < 0)
392 goto out;
393
394 lock_kernel();
395 /* Use local locking if mounted with "-onolock" */
396 if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) {
397 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
398 /* If we were signalled we still need to ensure that
399 * we clean up any state on the server. We therefore
400 * record the lock call as having succeeded in order to
401 * ensure that locks_remove_posix() cleans it out when
402 * the process exits.
403 */
404 if (status == -EINTR || status == -ERESTARTSYS)
405 do_vfs_lock(filp, fl);
406 } else
407 status = do_vfs_lock(filp, fl);
408 unlock_kernel();
409 if (status < 0)
410 goto out;
411 /*
412 * Make sure we clear the cache whenever we try to get the lock.
413 * This makes locking act as a cache coherency point.
414 */
415 filemap_fdatawrite(filp->f_mapping);
416 down(&inode->i_sem);
417 nfs_wb_all(inode); /* we may have slept */
418 up(&inode->i_sem);
419 filemap_fdatawait(filp->f_mapping);
420 nfs_zap_caches(inode);
421out:
422 rpc_clnt_sigunmask(NFS_CLIENT(inode), &oldset);
423 return status;
424}
425
426/*
427 * Lock a (portion of) a file
428 */
429static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
430{
431 struct inode * inode = filp->f_mapping->host;
432
433 dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
434 inode->i_sb->s_id, inode->i_ino,
435 fl->fl_type, fl->fl_flags,
436 (long long)fl->fl_start, (long long)fl->fl_end);
437
438 if (!inode)
439 return -EINVAL;
440
441 /* No mandatory locks over NFS */
442 if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
443 return -ENOLCK;
444
445 if (IS_GETLK(cmd))
446 return do_getlk(filp, cmd, fl);
447 if (fl->fl_type == F_UNLCK)
448 return do_unlk(filp, cmd, fl);
449 return do_setlk(filp, cmd, fl);
450}
451
452/*
453 * Lock a (portion of) a file
454 */
455static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
456{
457 struct inode * inode = filp->f_mapping->host;
458
459 dprintk("NFS: nfs_flock(f=%s/%ld, t=%x, fl=%x)\n",
460 inode->i_sb->s_id, inode->i_ino,
461 fl->fl_type, fl->fl_flags);
462
463 if (!inode)
464 return -EINVAL;
465
466 /*
467 * No BSD flocks over NFS allowed.
468 * Note: we could try to fake a POSIX lock request here by
469 * using ((u32) filp | 0x80000000) or some such as the pid.
470 * Not sure whether that would be unique, though, or whether
471 * that would break in other places.
472 */
473 if (!(fl->fl_flags & FL_FLOCK))
474 return -ENOLCK;
475
476 /* We're simulating flock() locks using posix locks on the server */
477 fl->fl_owner = (fl_owner_t)filp;
478 fl->fl_start = 0;
479 fl->fl_end = OFFSET_MAX;
480
481 if (fl->fl_type == F_UNLCK)
482 return do_unlk(filp, cmd, fl);
483 return do_setlk(filp, cmd, fl);
484}