blob: dae67048baba345fcbd6358e4a84fd890f834633 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * file.c
3 *
4 * Copyright (C) 1995, 1996, 1997 by Paal-Kr. Engstad and Volker Lendecke
5 * Copyright (C) 1997 by Volker Lendecke
6 *
7 * Please add a note about your changes to smbfs in the ChangeLog file.
8 */
9
10#include <linux/time.h>
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/fcntl.h>
14#include <linux/stat.h>
15#include <linux/mm.h>
16#include <linux/slab.h>
17#include <linux/pagemap.h>
18#include <linux/smp_lock.h>
19#include <linux/net.h>
20
21#include <asm/uaccess.h>
22#include <asm/system.h>
23
24#include <linux/smbno.h>
25#include <linux/smb_fs.h>
26
27#include "smb_debug.h"
28#include "proto.h"
29
30static int
31smb_fsync(struct file *file, struct dentry * dentry, int datasync)
32{
33 struct smb_sb_info *server = server_from_dentry(dentry);
34 int result;
35
36 VERBOSE("sync file %s/%s\n", DENTRY_PATH(dentry));
37
38 /*
39 * The VFS will writepage() all dirty pages for us, but we
40 * should send a SMBflush to the server, letting it know that
41 * we want things synchronized with actual storage.
42 *
43 * Note: this function requires all pages to have been written already
44 * (should be ok with writepage_sync)
45 */
46 result = smb_proc_flush(server, SMB_I(dentry->d_inode)->fileid);
47 return result;
48}
49
50/*
51 * Read a page synchronously.
52 */
53static int
54smb_readpage_sync(struct dentry *dentry, struct page *page)
55{
56 char *buffer = kmap(page);
57 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
58 struct smb_sb_info *server = server_from_dentry(dentry);
59 unsigned int rsize = smb_get_rsize(server);
60 int count = PAGE_SIZE;
61 int result;
62
63 VERBOSE("file %s/%s, count=%d@%Ld, rsize=%d\n",
64 DENTRY_PATH(dentry), count, offset, rsize);
65
66 result = smb_open(dentry, SMB_O_RDONLY);
67 if (result < 0)
68 goto io_error;
69
70 do {
71 if (count < rsize)
72 rsize = count;
73
74 result = server->ops->read(dentry->d_inode,offset,rsize,buffer);
75 if (result < 0)
76 goto io_error;
77
78 count -= result;
79 offset += result;
80 buffer += result;
81 dentry->d_inode->i_atime =
82 current_fs_time(dentry->d_inode->i_sb);
83 if (result < rsize)
84 break;
85 } while (count);
86
87 memset(buffer, 0, count);
88 flush_dcache_page(page);
89 SetPageUptodate(page);
90 result = 0;
91
92io_error:
93 kunmap(page);
94 unlock_page(page);
95 return result;
96}
97
98/*
99 * We are called with the page locked and we unlock it when done.
100 */
101static int
102smb_readpage(struct file *file, struct page *page)
103{
104 int error;
105 struct dentry *dentry = file->f_dentry;
106
107 page_cache_get(page);
108 error = smb_readpage_sync(dentry, page);
109 page_cache_release(page);
110 return error;
111}
112
113/*
114 * Write a page synchronously.
115 * Offset is the data offset within the page.
116 */
117static int
118smb_writepage_sync(struct inode *inode, struct page *page,
119 unsigned long pageoffset, unsigned int count)
120{
121 loff_t offset;
122 char *buffer = kmap(page) + pageoffset;
123 struct smb_sb_info *server = server_from_inode(inode);
124 unsigned int wsize = smb_get_wsize(server);
125 int ret = 0;
126
127 offset = ((loff_t)page->index << PAGE_CACHE_SHIFT) + pageoffset;
128 VERBOSE("file ino=%ld, fileid=%d, count=%d@%Ld, wsize=%d\n",
129 inode->i_ino, SMB_I(inode)->fileid, count, offset, wsize);
130
131 do {
132 int write_ret;
133
134 if (count < wsize)
135 wsize = count;
136
137 write_ret = server->ops->write(inode, offset, wsize, buffer);
138 if (write_ret < 0) {
139 PARANOIA("failed write, wsize=%d, write_ret=%d\n",
140 wsize, write_ret);
141 ret = write_ret;
142 break;
143 }
144 /* N.B. what if result < wsize?? */
145#ifdef SMBFS_PARANOIA
146 if (write_ret < wsize)
147 PARANOIA("short write, wsize=%d, write_ret=%d\n",
148 wsize, write_ret);
149#endif
150 buffer += wsize;
151 offset += wsize;
152 count -= wsize;
153 /*
154 * Update the inode now rather than waiting for a refresh.
155 */
156 inode->i_mtime = inode->i_atime = current_fs_time(inode->i_sb);
157 SMB_I(inode)->flags |= SMB_F_LOCALWRITE;
158 if (offset > inode->i_size)
159 inode->i_size = offset;
160 } while (count);
161
162 kunmap(page);
163 return ret;
164}
165
166/*
167 * Write a page to the server. This will be used for NFS swapping only
168 * (for now), and we currently do this synchronously only.
169 *
170 * We are called with the page locked and we unlock it when done.
171 */
172static int
173smb_writepage(struct page *page, struct writeback_control *wbc)
174{
175 struct address_space *mapping = page->mapping;
176 struct inode *inode;
177 unsigned long end_index;
178 unsigned offset = PAGE_CACHE_SIZE;
179 int err;
180
Eric Sesterhenn5df0d312006-04-01 01:16:26 +0200181 BUG_ON(!mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 inode = mapping->host;
Eric Sesterhenn5df0d312006-04-01 01:16:26 +0200183 BUG_ON(!inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184
185 end_index = inode->i_size >> PAGE_CACHE_SHIFT;
186
187 /* easy case */
188 if (page->index < end_index)
189 goto do_it;
190 /* things got complicated... */
191 offset = inode->i_size & (PAGE_CACHE_SIZE-1);
192 /* OK, are we completely out? */
193 if (page->index >= end_index+1 || !offset)
194 return 0; /* truncated - don't care */
195do_it:
196 page_cache_get(page);
197 err = smb_writepage_sync(inode, page, 0, offset);
198 SetPageUptodate(page);
199 unlock_page(page);
200 page_cache_release(page);
201 return err;
202}
203
204static int
205smb_updatepage(struct file *file, struct page *page, unsigned long offset,
206 unsigned int count)
207{
208 struct dentry *dentry = file->f_dentry;
209
Andrew Morton54b21a72006-01-08 01:03:05 -0800210 DEBUG1("(%s/%s %d@%lld)\n", DENTRY_PATH(dentry), count,
211 ((unsigned long long)page->index << PAGE_CACHE_SHIFT) + offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
213 return smb_writepage_sync(dentry->d_inode, page, offset, count);
214}
215
216static ssize_t
217smb_file_read(struct file * file, char __user * buf, size_t count, loff_t *ppos)
218{
219 struct dentry * dentry = file->f_dentry;
220 ssize_t status;
221
222 VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry),
223 (unsigned long) count, (unsigned long) *ppos);
224
225 status = smb_revalidate_inode(dentry);
226 if (status) {
227 PARANOIA("%s/%s validation failed, error=%Zd\n",
228 DENTRY_PATH(dentry), status);
229 goto out;
230 }
231
232 VERBOSE("before read, size=%ld, flags=%x, atime=%ld\n",
233 (long)dentry->d_inode->i_size,
234 dentry->d_inode->i_flags, dentry->d_inode->i_atime);
235
236 status = generic_file_read(file, buf, count, ppos);
237out:
238 return status;
239}
240
241static int
242smb_file_mmap(struct file * file, struct vm_area_struct * vma)
243{
244 struct dentry * dentry = file->f_dentry;
245 int status;
246
247 VERBOSE("file %s/%s, address %lu - %lu\n",
248 DENTRY_PATH(dentry), vma->vm_start, vma->vm_end);
249
250 status = smb_revalidate_inode(dentry);
251 if (status) {
252 PARANOIA("%s/%s validation failed, error=%d\n",
253 DENTRY_PATH(dentry), status);
254 goto out;
255 }
256 status = generic_file_mmap(file, vma);
257out:
258 return status;
259}
260
261static ssize_t
262smb_file_sendfile(struct file *file, loff_t *ppos,
263 size_t count, read_actor_t actor, void *target)
264{
265 struct dentry *dentry = file->f_dentry;
266 ssize_t status;
267
268 VERBOSE("file %s/%s, pos=%Ld, count=%d\n",
269 DENTRY_PATH(dentry), *ppos, count);
270
271 status = smb_revalidate_inode(dentry);
272 if (status) {
273 PARANOIA("%s/%s validation failed, error=%Zd\n",
274 DENTRY_PATH(dentry), status);
275 goto out;
276 }
277 status = generic_file_sendfile(file, ppos, count, actor, target);
278out:
279 return status;
280}
281
282/*
283 * This does the "real" work of the write. The generic routine has
284 * allocated the page, locked it, done all the page alignment stuff
285 * calculations etc. Now we should just copy the data from user
286 * space and write it back to the real medium..
287 *
288 * If the writer ends up delaying the write, the writer needs to
289 * increment the page use counts until he is done with the page.
290 */
291static int smb_prepare_write(struct file *file, struct page *page,
292 unsigned offset, unsigned to)
293{
294 return 0;
295}
296
297static int smb_commit_write(struct file *file, struct page *page,
298 unsigned offset, unsigned to)
299{
300 int status;
301
302 status = -EFAULT;
303 lock_kernel();
304 status = smb_updatepage(file, page, offset, to-offset);
305 unlock_kernel();
306 return status;
307}
308
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700309const struct address_space_operations smb_file_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 .readpage = smb_readpage,
311 .writepage = smb_writepage,
312 .prepare_write = smb_prepare_write,
313 .commit_write = smb_commit_write
314};
315
316/*
317 * Write to a file (through the page cache).
318 */
319static ssize_t
320smb_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
321{
322 struct dentry * dentry = file->f_dentry;
323 ssize_t result;
324
325 VERBOSE("file %s/%s, count=%lu@%lu\n",
326 DENTRY_PATH(dentry),
327 (unsigned long) count, (unsigned long) *ppos);
328
329 result = smb_revalidate_inode(dentry);
330 if (result) {
331 PARANOIA("%s/%s validation failed, error=%Zd\n",
332 DENTRY_PATH(dentry), result);
333 goto out;
334 }
335
336 result = smb_open(dentry, SMB_O_WRONLY);
337 if (result)
338 goto out;
339
340 if (count > 0) {
341 result = generic_file_write(file, buf, count, ppos);
342 VERBOSE("pos=%ld, size=%ld, mtime=%ld, atime=%ld\n",
343 (long) file->f_pos, (long) dentry->d_inode->i_size,
344 dentry->d_inode->i_mtime, dentry->d_inode->i_atime);
345 }
346out:
347 return result;
348}
349
350static int
351smb_file_open(struct inode *inode, struct file * file)
352{
353 int result;
354 struct dentry *dentry = file->f_dentry;
355 int smb_mode = (file->f_mode & O_ACCMODE) - 1;
356
357 lock_kernel();
358 result = smb_open(dentry, smb_mode);
359 if (result)
360 goto out;
361 SMB_I(inode)->openers++;
362out:
363 unlock_kernel();
364 return result;
365}
366
367static int
368smb_file_release(struct inode *inode, struct file * file)
369{
370 lock_kernel();
371 if (!--SMB_I(inode)->openers) {
372 /* We must flush any dirty pages now as we won't be able to
373 write anything after close. mmap can trigger this.
374 "openers" should perhaps include mmap'ers ... */
OGAWA Hirofumi28fd1292006-01-08 01:02:14 -0800375 filemap_write_and_wait(inode->i_mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 smb_close(inode);
377 }
378 unlock_kernel();
379 return 0;
380}
381
382/*
383 * Check whether the required access is compatible with
384 * an inode's permission. SMB doesn't recognize superuser
385 * privileges, so we need our own check for this.
386 */
387static int
388smb_file_permission(struct inode *inode, int mask, struct nameidata *nd)
389{
390 int mode = inode->i_mode;
391 int error = 0;
392
393 VERBOSE("mode=%x, mask=%x\n", mode, mask);
394
395 /* Look at user permissions */
396 mode >>= 6;
397 if ((mode & 7 & mask) != mask)
398 error = -EACCES;
399 return error;
400}
401
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800402const struct file_operations smb_file_operations =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403{
404 .llseek = remote_llseek,
405 .read = smb_file_read,
406 .write = smb_file_write,
407 .ioctl = smb_ioctl,
408 .mmap = smb_file_mmap,
409 .open = smb_file_open,
410 .release = smb_file_release,
411 .fsync = smb_fsync,
412 .sendfile = smb_file_sendfile,
413};
414
415struct inode_operations smb_file_inode_operations =
416{
417 .permission = smb_file_permission,
418 .getattr = smb_getattr,
419 .setattr = smb_notify_change,
420};