radix-tree: add radix_tree_prev_hole()
[linux-2.6/mini2440.git] / fs / smbfs / file.c
blob92d5e8ffb63923062680d09906f8baa7ad53d8c8
1 /*
2 * file.c
4 * Copyright (C) 1995, 1996, 1997 by Paal-Kr. Engstad and Volker Lendecke
5 * Copyright (C) 1997 by Volker Lendecke
7 * Please add a note about your changes to smbfs in the ChangeLog file.
8 */
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 #include <linux/aio.h>
22 #include <asm/uaccess.h>
23 #include <asm/system.h>
25 #include <linux/smbno.h>
26 #include <linux/smb_fs.h>
28 #include "smb_debug.h"
29 #include "proto.h"
31 static int
32 smb_fsync(struct file *file, struct dentry * dentry, int datasync)
34 struct smb_sb_info *server = server_from_dentry(dentry);
35 int result;
37 VERBOSE("sync file %s/%s\n", DENTRY_PATH(dentry));
40 * The VFS will writepage() all dirty pages for us, but we
41 * should send a SMBflush to the server, letting it know that
42 * we want things synchronized with actual storage.
44 * Note: this function requires all pages to have been written already
45 * (should be ok with writepage_sync)
47 result = smb_proc_flush(server, SMB_I(dentry->d_inode)->fileid);
48 return result;
52 * Read a page synchronously.
54 static int
55 smb_readpage_sync(struct dentry *dentry, struct page *page)
57 char *buffer = kmap(page);
58 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
59 struct smb_sb_info *server = server_from_dentry(dentry);
60 unsigned int rsize = smb_get_rsize(server);
61 int count = PAGE_SIZE;
62 int result;
64 VERBOSE("file %s/%s, count=%d@%Ld, rsize=%d\n",
65 DENTRY_PATH(dentry), count, offset, rsize);
67 result = smb_open(dentry, SMB_O_RDONLY);
68 if (result < 0)
69 goto io_error;
71 do {
72 if (count < rsize)
73 rsize = count;
75 result = server->ops->read(dentry->d_inode,offset,rsize,buffer);
76 if (result < 0)
77 goto io_error;
79 count -= result;
80 offset += result;
81 buffer += result;
82 dentry->d_inode->i_atime =
83 current_fs_time(dentry->d_inode->i_sb);
84 if (result < rsize)
85 break;
86 } while (count);
88 memset(buffer, 0, count);
89 flush_dcache_page(page);
90 SetPageUptodate(page);
91 result = 0;
93 io_error:
94 kunmap(page);
95 unlock_page(page);
96 return result;
100 * We are called with the page locked and we unlock it when done.
102 static int
103 smb_readpage(struct file *file, struct page *page)
105 int error;
106 struct dentry *dentry = file->f_path.dentry;
108 page_cache_get(page);
109 error = smb_readpage_sync(dentry, page);
110 page_cache_release(page);
111 return error;
115 * Write a page synchronously.
116 * Offset is the data offset within the page.
118 static int
119 smb_writepage_sync(struct inode *inode, struct page *page,
120 unsigned long pageoffset, unsigned int count)
122 loff_t offset;
123 char *buffer = kmap(page) + pageoffset;
124 struct smb_sb_info *server = server_from_inode(inode);
125 unsigned int wsize = smb_get_wsize(server);
126 int ret = 0;
128 offset = ((loff_t)page->index << PAGE_CACHE_SHIFT) + pageoffset;
129 VERBOSE("file ino=%ld, fileid=%d, count=%d@%Ld, wsize=%d\n",
130 inode->i_ino, SMB_I(inode)->fileid, count, offset, wsize);
132 do {
133 int write_ret;
135 if (count < wsize)
136 wsize = count;
138 write_ret = server->ops->write(inode, offset, wsize, buffer);
139 if (write_ret < 0) {
140 PARANOIA("failed write, wsize=%d, write_ret=%d\n",
141 wsize, write_ret);
142 ret = write_ret;
143 break;
145 /* N.B. what if result < wsize?? */
146 #ifdef SMBFS_PARANOIA
147 if (write_ret < wsize)
148 PARANOIA("short write, wsize=%d, write_ret=%d\n",
149 wsize, write_ret);
150 #endif
151 buffer += wsize;
152 offset += wsize;
153 count -= wsize;
155 * Update the inode now rather than waiting for a refresh.
157 inode->i_mtime = inode->i_atime = current_fs_time(inode->i_sb);
158 SMB_I(inode)->flags |= SMB_F_LOCALWRITE;
159 if (offset > inode->i_size)
160 inode->i_size = offset;
161 } while (count);
163 kunmap(page);
164 return ret;
168 * Write a page to the server. This will be used for NFS swapping only
169 * (for now), and we currently do this synchronously only.
171 * We are called with the page locked and we unlock it when done.
173 static int
174 smb_writepage(struct page *page, struct writeback_control *wbc)
176 struct address_space *mapping = page->mapping;
177 struct inode *inode;
178 unsigned long end_index;
179 unsigned offset = PAGE_CACHE_SIZE;
180 int err;
182 BUG_ON(!mapping);
183 inode = mapping->host;
184 BUG_ON(!inode);
186 end_index = inode->i_size >> PAGE_CACHE_SHIFT;
188 /* easy case */
189 if (page->index < end_index)
190 goto do_it;
191 /* things got complicated... */
192 offset = inode->i_size & (PAGE_CACHE_SIZE-1);
193 /* OK, are we completely out? */
194 if (page->index >= end_index+1 || !offset)
195 return 0; /* truncated - don't care */
196 do_it:
197 page_cache_get(page);
198 err = smb_writepage_sync(inode, page, 0, offset);
199 SetPageUptodate(page);
200 unlock_page(page);
201 page_cache_release(page);
202 return err;
205 static int
206 smb_updatepage(struct file *file, struct page *page, unsigned long offset,
207 unsigned int count)
209 struct dentry *dentry = file->f_path.dentry;
211 DEBUG1("(%s/%s %d@%lld)\n", DENTRY_PATH(dentry), count,
212 ((unsigned long long)page->index << PAGE_CACHE_SHIFT) + offset);
214 return smb_writepage_sync(dentry->d_inode, page, offset, count);
217 static ssize_t
218 smb_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
219 unsigned long nr_segs, loff_t pos)
221 struct file * file = iocb->ki_filp;
222 struct dentry * dentry = file->f_path.dentry;
223 ssize_t status;
225 VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry),
226 (unsigned long) iocb->ki_left, (unsigned long) pos);
228 status = smb_revalidate_inode(dentry);
229 if (status) {
230 PARANOIA("%s/%s validation failed, error=%Zd\n",
231 DENTRY_PATH(dentry), status);
232 goto out;
235 VERBOSE("before read, size=%ld, flags=%x, atime=%ld\n",
236 (long)dentry->d_inode->i_size,
237 dentry->d_inode->i_flags, dentry->d_inode->i_atime.tv_sec);
239 status = generic_file_aio_read(iocb, iov, nr_segs, pos);
240 out:
241 return status;
244 static int
245 smb_file_mmap(struct file * file, struct vm_area_struct * vma)
247 struct dentry * dentry = file->f_path.dentry;
248 int status;
250 VERBOSE("file %s/%s, address %lu - %lu\n",
251 DENTRY_PATH(dentry), vma->vm_start, vma->vm_end);
253 status = smb_revalidate_inode(dentry);
254 if (status) {
255 PARANOIA("%s/%s validation failed, error=%d\n",
256 DENTRY_PATH(dentry), status);
257 goto out;
259 status = generic_file_mmap(file, vma);
260 out:
261 return status;
264 static ssize_t
265 smb_file_splice_read(struct file *file, loff_t *ppos,
266 struct pipe_inode_info *pipe, size_t count,
267 unsigned int flags)
269 struct dentry *dentry = file->f_path.dentry;
270 ssize_t status;
272 VERBOSE("file %s/%s, pos=%Ld, count=%lu\n",
273 DENTRY_PATH(dentry), *ppos, count);
275 status = smb_revalidate_inode(dentry);
276 if (status) {
277 PARANOIA("%s/%s validation failed, error=%Zd\n",
278 DENTRY_PATH(dentry), status);
279 goto out;
281 status = generic_file_splice_read(file, ppos, pipe, count, flags);
282 out:
283 return status;
287 * This does the "real" work of the write. The generic routine has
288 * allocated the page, locked it, done all the page alignment stuff
289 * calculations etc. Now we should just copy the data from user
290 * space and write it back to the real medium..
292 * If the writer ends up delaying the write, the writer needs to
293 * increment the page use counts until he is done with the page.
295 static int smb_write_begin(struct file *file, struct address_space *mapping,
296 loff_t pos, unsigned len, unsigned flags,
297 struct page **pagep, void **fsdata)
299 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
300 *pagep = grab_cache_page_write_begin(mapping, index, flags);
301 if (!*pagep)
302 return -ENOMEM;
303 return 0;
306 static int smb_write_end(struct file *file, struct address_space *mapping,
307 loff_t pos, unsigned len, unsigned copied,
308 struct page *page, void *fsdata)
310 int status;
311 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
313 lock_kernel();
314 status = smb_updatepage(file, page, offset, copied);
315 unlock_kernel();
317 if (!status) {
318 if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
319 SetPageUptodate(page);
320 status = copied;
323 unlock_page(page);
324 page_cache_release(page);
326 return status;
329 const struct address_space_operations smb_file_aops = {
330 .readpage = smb_readpage,
331 .writepage = smb_writepage,
332 .write_begin = smb_write_begin,
333 .write_end = smb_write_end,
337 * Write to a file (through the page cache).
339 static ssize_t
340 smb_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
341 unsigned long nr_segs, loff_t pos)
343 struct file * file = iocb->ki_filp;
344 struct dentry * dentry = file->f_path.dentry;
345 ssize_t result;
347 VERBOSE("file %s/%s, count=%lu@%lu\n",
348 DENTRY_PATH(dentry),
349 (unsigned long) iocb->ki_left, (unsigned long) pos);
351 result = smb_revalidate_inode(dentry);
352 if (result) {
353 PARANOIA("%s/%s validation failed, error=%Zd\n",
354 DENTRY_PATH(dentry), result);
355 goto out;
358 result = smb_open(dentry, SMB_O_WRONLY);
359 if (result)
360 goto out;
362 if (iocb->ki_left > 0) {
363 result = generic_file_aio_write(iocb, iov, nr_segs, pos);
364 VERBOSE("pos=%ld, size=%ld, mtime=%ld, atime=%ld\n",
365 (long) file->f_pos, (long) dentry->d_inode->i_size,
366 dentry->d_inode->i_mtime.tv_sec,
367 dentry->d_inode->i_atime.tv_sec);
369 out:
370 return result;
373 static int
374 smb_file_open(struct inode *inode, struct file * file)
376 int result;
377 struct dentry *dentry = file->f_path.dentry;
378 int smb_mode = (file->f_mode & O_ACCMODE) - 1;
380 lock_kernel();
381 result = smb_open(dentry, smb_mode);
382 if (result)
383 goto out;
384 SMB_I(inode)->openers++;
385 out:
386 unlock_kernel();
387 return result;
390 static int
391 smb_file_release(struct inode *inode, struct file * file)
393 lock_kernel();
394 if (!--SMB_I(inode)->openers) {
395 /* We must flush any dirty pages now as we won't be able to
396 write anything after close. mmap can trigger this.
397 "openers" should perhaps include mmap'ers ... */
398 filemap_write_and_wait(inode->i_mapping);
399 smb_close(inode);
401 unlock_kernel();
402 return 0;
406 * Check whether the required access is compatible with
407 * an inode's permission. SMB doesn't recognize superuser
408 * privileges, so we need our own check for this.
410 static int
411 smb_file_permission(struct inode *inode, int mask)
413 int mode = inode->i_mode;
414 int error = 0;
416 VERBOSE("mode=%x, mask=%x\n", mode, mask);
418 /* Look at user permissions */
419 mode >>= 6;
420 if (mask & ~mode & (MAY_READ | MAY_WRITE | MAY_EXEC))
421 error = -EACCES;
422 return error;
425 static loff_t smb_remote_llseek(struct file *file, loff_t offset, int origin)
427 loff_t ret;
428 lock_kernel();
429 ret = generic_file_llseek_unlocked(file, offset, origin);
430 unlock_kernel();
431 return ret;
434 const struct file_operations smb_file_operations =
436 .llseek = smb_remote_llseek,
437 .read = do_sync_read,
438 .aio_read = smb_file_aio_read,
439 .write = do_sync_write,
440 .aio_write = smb_file_aio_write,
441 .ioctl = smb_ioctl,
442 .mmap = smb_file_mmap,
443 .open = smb_file_open,
444 .release = smb_file_release,
445 .fsync = smb_fsync,
446 .splice_read = smb_file_splice_read,
449 const struct inode_operations smb_file_inode_operations =
451 .permission = smb_file_permission,
452 .getattr = smb_getattr,
453 .setattr = smb_notify_change,