Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
[linux-2.6] / fs / xfs / linux-2.6 / xfs_file.c
1 /*
2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_bit.h"
20 #include "xfs_log.h"
21 #include "xfs_inum.h"
22 #include "xfs_sb.h"
23 #include "xfs_ag.h"
24 #include "xfs_dir2.h"
25 #include "xfs_trans.h"
26 #include "xfs_dmapi.h"
27 #include "xfs_mount.h"
28 #include "xfs_bmap_btree.h"
29 #include "xfs_alloc_btree.h"
30 #include "xfs_ialloc_btree.h"
31 #include "xfs_alloc.h"
32 #include "xfs_btree.h"
33 #include "xfs_attr_sf.h"
34 #include "xfs_dir2_sf.h"
35 #include "xfs_dinode.h"
36 #include "xfs_inode.h"
37 #include "xfs_error.h"
38 #include "xfs_rw.h"
39 #include "xfs_ioctl32.h"
40
41 #include <linux/dcache.h>
42 #include <linux/smp_lock.h>
43
44 static struct vm_operations_struct xfs_file_vm_ops;
45 #ifdef CONFIG_XFS_DMAPI
46 static struct vm_operations_struct xfs_dmapi_file_vm_ops;
47 #endif
48
49 STATIC inline ssize_t
50 __xfs_file_read(
51         struct kiocb            *iocb,
52         const struct iovec      *iov,
53         unsigned long           nr_segs,
54         int                     ioflags,
55         loff_t                  pos)
56 {
57         struct file             *file = iocb->ki_filp;
58         bhv_vnode_t             *vp = vn_from_inode(file->f_path.dentry->d_inode);
59
60         BUG_ON(iocb->ki_pos != pos);
61         if (unlikely(file->f_flags & O_DIRECT))
62                 ioflags |= IO_ISDIRECT;
63         return bhv_vop_read(vp, iocb, iov, nr_segs, &iocb->ki_pos,
64                                 ioflags, NULL);
65 }
66
67 STATIC ssize_t
68 xfs_file_aio_read(
69         struct kiocb            *iocb,
70         const struct iovec      *iov,
71         unsigned long           nr_segs,
72         loff_t                  pos)
73 {
74         return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO, pos);
75 }
76
77 STATIC ssize_t
78 xfs_file_aio_read_invis(
79         struct kiocb            *iocb,
80         const struct iovec      *iov,
81         unsigned long           nr_segs,
82         loff_t                  pos)
83 {
84         return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
85 }
86
87 STATIC inline ssize_t
88 __xfs_file_write(
89         struct kiocb            *iocb,
90         const struct iovec      *iov,
91         unsigned long           nr_segs,
92         int                     ioflags,
93         loff_t                  pos)
94 {
95         struct file     *file = iocb->ki_filp;
96         struct inode    *inode = file->f_mapping->host;
97         bhv_vnode_t     *vp = vn_from_inode(inode);
98
99         BUG_ON(iocb->ki_pos != pos);
100         if (unlikely(file->f_flags & O_DIRECT))
101                 ioflags |= IO_ISDIRECT;
102         return bhv_vop_write(vp, iocb, iov, nr_segs, &iocb->ki_pos,
103                                 ioflags, NULL);
104 }
105
106 STATIC ssize_t
107 xfs_file_aio_write(
108         struct kiocb            *iocb,
109         const struct iovec      *iov,
110         unsigned long           nr_segs,
111         loff_t                  pos)
112 {
113         return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO, pos);
114 }
115
116 STATIC ssize_t
117 xfs_file_aio_write_invis(
118         struct kiocb            *iocb,
119         const struct iovec      *iov,
120         unsigned long           nr_segs,
121         loff_t                  pos)
122 {
123         return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
124 }
125
126 STATIC ssize_t
127 xfs_file_sendfile(
128         struct file             *filp,
129         loff_t                  *pos,
130         size_t                  count,
131         read_actor_t            actor,
132         void                    *target)
133 {
134         return bhv_vop_sendfile(vn_from_inode(filp->f_path.dentry->d_inode),
135                                 filp, pos, 0, count, actor, target, NULL);
136 }
137
138 STATIC ssize_t
139 xfs_file_sendfile_invis(
140         struct file             *filp,
141         loff_t                  *pos,
142         size_t                  count,
143         read_actor_t            actor,
144         void                    *target)
145 {
146         return bhv_vop_sendfile(vn_from_inode(filp->f_path.dentry->d_inode),
147                                 filp, pos, IO_INVIS, count, actor, target, NULL);
148 }
149
150 STATIC ssize_t
151 xfs_file_splice_read(
152         struct file             *infilp,
153         loff_t                  *ppos,
154         struct pipe_inode_info  *pipe,
155         size_t                  len,
156         unsigned int            flags)
157 {
158         return bhv_vop_splice_read(vn_from_inode(infilp->f_path.dentry->d_inode),
159                                    infilp, ppos, pipe, len, flags, 0, NULL);
160 }
161
162 STATIC ssize_t
163 xfs_file_splice_read_invis(
164         struct file             *infilp,
165         loff_t                  *ppos,
166         struct pipe_inode_info  *pipe,
167         size_t                  len,
168         unsigned int            flags)
169 {
170         return bhv_vop_splice_read(vn_from_inode(infilp->f_path.dentry->d_inode),
171                                    infilp, ppos, pipe, len, flags, IO_INVIS,
172                                    NULL);
173 }
174
175 STATIC ssize_t
176 xfs_file_splice_write(
177         struct pipe_inode_info  *pipe,
178         struct file             *outfilp,
179         loff_t                  *ppos,
180         size_t                  len,
181         unsigned int            flags)
182 {
183         return bhv_vop_splice_write(vn_from_inode(outfilp->f_path.dentry->d_inode),
184                                     pipe, outfilp, ppos, len, flags, 0, NULL);
185 }
186
187 STATIC ssize_t
188 xfs_file_splice_write_invis(
189         struct pipe_inode_info  *pipe,
190         struct file             *outfilp,
191         loff_t                  *ppos,
192         size_t                  len,
193         unsigned int            flags)
194 {
195         return bhv_vop_splice_write(vn_from_inode(outfilp->f_path.dentry->d_inode),
196                                     pipe, outfilp, ppos, len, flags, IO_INVIS,
197                                     NULL);
198 }
199
200 STATIC int
201 xfs_file_open(
202         struct inode    *inode,
203         struct file     *filp)
204 {
205         if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
206                 return -EFBIG;
207         return -bhv_vop_open(vn_from_inode(inode), NULL);
208 }
209
210 STATIC int
211 xfs_file_close(
212         struct file     *filp,
213         fl_owner_t      id)
214 {
215         return -bhv_vop_close(vn_from_inode(filp->f_path.dentry->d_inode), 0,
216                                 file_count(filp) > 1 ? L_FALSE : L_TRUE, NULL);
217 }
218
219 STATIC int
220 xfs_file_release(
221         struct inode    *inode,
222         struct file     *filp)
223 {
224         bhv_vnode_t     *vp = vn_from_inode(inode);
225
226         if (vp)
227                 return -bhv_vop_release(vp);
228         return 0;
229 }
230
231 STATIC int
232 xfs_file_fsync(
233         struct file     *filp,
234         struct dentry   *dentry,
235         int             datasync)
236 {
237         bhv_vnode_t     *vp = vn_from_inode(dentry->d_inode);
238         int             flags = FSYNC_WAIT;
239
240         if (datasync)
241                 flags |= FSYNC_DATA;
242         if (VN_TRUNC(vp))
243                 VUNTRUNCATE(vp);
244         return -bhv_vop_fsync(vp, flags, NULL, (xfs_off_t)0, (xfs_off_t)-1);
245 }
246
247 #ifdef CONFIG_XFS_DMAPI
248 STATIC struct page *
249 xfs_vm_nopage(
250         struct vm_area_struct   *area,
251         unsigned long           address,
252         int                     *type)
253 {
254         struct inode    *inode = area->vm_file->f_path.dentry->d_inode;
255         bhv_vnode_t     *vp = vn_from_inode(inode);
256
257         ASSERT_ALWAYS(vp->v_vfsp->vfs_flag & VFS_DMI);
258         if (XFS_SEND_MMAP(XFS_VFSTOM(vp->v_vfsp), area, 0))
259                 return NULL;
260         return filemap_nopage(area, address, type);
261 }
262 #endif /* CONFIG_XFS_DMAPI */
263
264 STATIC int
265 xfs_file_readdir(
266         struct file     *filp,
267         void            *dirent,
268         filldir_t       filldir)
269 {
270         int             error = 0;
271         bhv_vnode_t     *vp = vn_from_inode(filp->f_path.dentry->d_inode);
272         uio_t           uio;
273         iovec_t         iov;
274         int             eof = 0;
275         caddr_t         read_buf;
276         int             namelen, size = 0;
277         size_t          rlen = PAGE_CACHE_SIZE;
278         xfs_off_t       start_offset, curr_offset;
279         xfs_dirent_t    *dbp = NULL;
280
281         /* Try fairly hard to get memory */
282         do {
283                 if ((read_buf = kmalloc(rlen, GFP_KERNEL)))
284                         break;
285                 rlen >>= 1;
286         } while (rlen >= 1024);
287
288         if (read_buf == NULL)
289                 return -ENOMEM;
290
291         uio.uio_iov = &iov;
292         uio.uio_segflg = UIO_SYSSPACE;
293         curr_offset = filp->f_pos;
294         if (filp->f_pos != 0x7fffffff)
295                 uio.uio_offset = filp->f_pos;
296         else
297                 uio.uio_offset = 0xffffffff;
298
299         while (!eof) {
300                 uio.uio_resid = iov.iov_len = rlen;
301                 iov.iov_base = read_buf;
302                 uio.uio_iovcnt = 1;
303
304                 start_offset = uio.uio_offset;
305
306                 error = bhv_vop_readdir(vp, &uio, NULL, &eof);
307                 if ((uio.uio_offset == start_offset) || error) {
308                         size = 0;
309                         break;
310                 }
311
312                 size = rlen - uio.uio_resid;
313                 dbp = (xfs_dirent_t *)read_buf;
314                 while (size > 0) {
315                         namelen = strlen(dbp->d_name);
316
317                         if (filldir(dirent, dbp->d_name, namelen,
318                                         (loff_t) curr_offset & 0x7fffffff,
319                                         (ino_t) dbp->d_ino,
320                                         DT_UNKNOWN)) {
321                                 goto done;
322                         }
323                         size -= dbp->d_reclen;
324                         curr_offset = (loff_t)dbp->d_off /* & 0x7fffffff */;
325                         dbp = (xfs_dirent_t *)((char *)dbp + dbp->d_reclen);
326                 }
327         }
328 done:
329         if (!error) {
330                 if (size == 0)
331                         filp->f_pos = uio.uio_offset & 0x7fffffff;
332                 else if (dbp)
333                         filp->f_pos = curr_offset;
334         }
335
336         kfree(read_buf);
337         return -error;
338 }
339
340 STATIC int
341 xfs_file_mmap(
342         struct file     *filp,
343         struct vm_area_struct *vma)
344 {
345         vma->vm_ops = &xfs_file_vm_ops;
346
347 #ifdef CONFIG_XFS_DMAPI
348         if (vn_from_inode(filp->f_path.dentry->d_inode)->v_vfsp->vfs_flag & VFS_DMI)
349                 vma->vm_ops = &xfs_dmapi_file_vm_ops;
350 #endif /* CONFIG_XFS_DMAPI */
351
352         file_accessed(filp);
353         return 0;
354 }
355
356 STATIC long
357 xfs_file_ioctl(
358         struct file     *filp,
359         unsigned int    cmd,
360         unsigned long   p)
361 {
362         int             error;
363         struct inode    *inode = filp->f_path.dentry->d_inode;
364         bhv_vnode_t     *vp = vn_from_inode(inode);
365
366         error = bhv_vop_ioctl(vp, inode, filp, 0, cmd, (void __user *)p);
367         VMODIFY(vp);
368
369         /* NOTE:  some of the ioctl's return positive #'s as a
370          *        byte count indicating success, such as
371          *        readlink_by_handle.  So we don't "sign flip"
372          *        like most other routines.  This means true
373          *        errors need to be returned as a negative value.
374          */
375         return error;
376 }
377
378 STATIC long
379 xfs_file_ioctl_invis(
380         struct file     *filp,
381         unsigned int    cmd,
382         unsigned long   p)
383 {
384         int             error;
385         struct inode    *inode = filp->f_path.dentry->d_inode;
386         bhv_vnode_t     *vp = vn_from_inode(inode);
387
388         error = bhv_vop_ioctl(vp, inode, filp, IO_INVIS, cmd, (void __user *)p);
389         VMODIFY(vp);
390
391         /* NOTE:  some of the ioctl's return positive #'s as a
392          *        byte count indicating success, such as
393          *        readlink_by_handle.  So we don't "sign flip"
394          *        like most other routines.  This means true
395          *        errors need to be returned as a negative value.
396          */
397         return error;
398 }
399
400 #ifdef CONFIG_XFS_DMAPI
401 #ifdef HAVE_VMOP_MPROTECT
402 STATIC int
403 xfs_vm_mprotect(
404         struct vm_area_struct *vma,
405         unsigned int    newflags)
406 {
407         bhv_vnode_t     *vp = vn_from_inode(vma->vm_file->f_path.dentry->d_inode);
408         int             error = 0;
409
410         if (vp->v_vfsp->vfs_flag & VFS_DMI) {
411                 if ((vma->vm_flags & VM_MAYSHARE) &&
412                     (newflags & VM_WRITE) && !(vma->vm_flags & VM_WRITE)) {
413                         xfs_mount_t     *mp = XFS_VFSTOM(vp->v_vfsp);
414
415                         error = XFS_SEND_MMAP(mp, vma, VM_WRITE);
416                     }
417         }
418         return error;
419 }
420 #endif /* HAVE_VMOP_MPROTECT */
421 #endif /* CONFIG_XFS_DMAPI */
422
423 #ifdef HAVE_FOP_OPEN_EXEC
424 /* If the user is attempting to execute a file that is offline then
425  * we have to trigger a DMAPI READ event before the file is marked as busy
426  * otherwise the invisible I/O will not be able to write to the file to bring
427  * it back online.
428  */
429 STATIC int
430 xfs_file_open_exec(
431         struct inode    *inode)
432 {
433         bhv_vnode_t     *vp = vn_from_inode(inode);
434
435         if (unlikely(vp->v_vfsp->vfs_flag & VFS_DMI)) {
436                 xfs_mount_t     *mp = XFS_VFSTOM(vp->v_vfsp);
437                 xfs_inode_t     *ip = xfs_vtoi(vp);
438
439                 if (!ip)
440                         return -EINVAL;
441                 if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_READ))
442                         return -XFS_SEND_DATA(mp, DM_EVENT_READ, vp,
443                                                0, 0, 0, NULL);
444         }
445         return 0;
446 }
447 #endif /* HAVE_FOP_OPEN_EXEC */
448
449 const struct file_operations xfs_file_operations = {
450         .llseek         = generic_file_llseek,
451         .read           = do_sync_read,
452         .write          = do_sync_write,
453         .aio_read       = xfs_file_aio_read,
454         .aio_write      = xfs_file_aio_write,
455         .sendfile       = xfs_file_sendfile,
456         .splice_read    = xfs_file_splice_read,
457         .splice_write   = xfs_file_splice_write,
458         .unlocked_ioctl = xfs_file_ioctl,
459 #ifdef CONFIG_COMPAT
460         .compat_ioctl   = xfs_file_compat_ioctl,
461 #endif
462         .mmap           = xfs_file_mmap,
463         .open           = xfs_file_open,
464         .flush          = xfs_file_close,
465         .release        = xfs_file_release,
466         .fsync          = xfs_file_fsync,
467 #ifdef HAVE_FOP_OPEN_EXEC
468         .open_exec      = xfs_file_open_exec,
469 #endif
470 };
471
472 const struct file_operations xfs_invis_file_operations = {
473         .llseek         = generic_file_llseek,
474         .read           = do_sync_read,
475         .write          = do_sync_write,
476         .aio_read       = xfs_file_aio_read_invis,
477         .aio_write      = xfs_file_aio_write_invis,
478         .sendfile       = xfs_file_sendfile_invis,
479         .splice_read    = xfs_file_splice_read_invis,
480         .splice_write   = xfs_file_splice_write_invis,
481         .unlocked_ioctl = xfs_file_ioctl_invis,
482 #ifdef CONFIG_COMPAT
483         .compat_ioctl   = xfs_file_compat_invis_ioctl,
484 #endif
485         .mmap           = xfs_file_mmap,
486         .open           = xfs_file_open,
487         .flush          = xfs_file_close,
488         .release        = xfs_file_release,
489         .fsync          = xfs_file_fsync,
490 };
491
492
493 const struct file_operations xfs_dir_file_operations = {
494         .read           = generic_read_dir,
495         .readdir        = xfs_file_readdir,
496         .unlocked_ioctl = xfs_file_ioctl,
497 #ifdef CONFIG_COMPAT
498         .compat_ioctl   = xfs_file_compat_ioctl,
499 #endif
500         .fsync          = xfs_file_fsync,
501 };
502
503 static struct vm_operations_struct xfs_file_vm_ops = {
504         .nopage         = filemap_nopage,
505         .populate       = filemap_populate,
506 };
507
508 #ifdef CONFIG_XFS_DMAPI
509 static struct vm_operations_struct xfs_dmapi_file_vm_ops = {
510         .nopage         = xfs_vm_nopage,
511         .populate       = filemap_populate,
512 #ifdef HAVE_VMOP_MPROTECT
513         .mprotect       = xfs_vm_mprotect,
514 #endif
515 };
516 #endif /* CONFIG_XFS_DMAPI */