2 * linux/fs/9p/vfs_file.c
4 * This file contians vfs file ops for 9P2000.
6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to:
20 * Free Software Foundation
21 * 51 Franklin Street, Fifth Floor
22 * Boston, MA 02111-1301 USA
26 #include <linux/module.h>
27 #include <linux/errno.h>
29 #include <linux/sched.h>
30 #include <linux/file.h>
31 #include <linux/stat.h>
32 #include <linux/string.h>
33 #include <linux/inet.h>
34 #include <linux/list.h>
35 #include <linux/pagemap.h>
36 #include <linux/utsname.h>
37 #include <asm/uaccess.h>
38 #include <linux/idr.h>
39 #include <linux/uio.h>
40 #include <linux/slab.h>
41 #include <net/9p/9p.h>
42 #include <net/9p/client.h>
49 static const struct vm_operations_struct v9fs_file_vm_ops;
50 static const struct vm_operations_struct v9fs_mmap_file_vm_ops;
53 * v9fs_file_open - open a file (or directory)
54 * @inode: inode to be opened
55 * @file: file being opened
59 int v9fs_file_open(struct inode *inode, struct file *file)
62 struct v9fs_inode *v9inode;
63 struct v9fs_session_info *v9ses;
67 p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
68 v9inode = V9FS_I(inode);
69 v9ses = v9fs_inode2v9ses(inode);
70 if (v9fs_proto_dotl(v9ses))
71 omode = v9fs_open_to_dotl_flags(file->f_flags);
73 omode = v9fs_uflags2omode(file->f_flags,
74 v9fs_proto_dotu(v9ses));
75 fid = file->private_data;
77 fid = v9fs_fid_clone(file->f_path.dentry);
81 err = p9_client_open(fid, omode);
86 if ((file->f_flags & O_APPEND) &&
87 (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
88 generic_file_llseek(file, 0, SEEK_END);
91 file->private_data = fid;
92 mutex_lock(&v9inode->v_mutex);
93 if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
94 !v9inode->writeback_fid &&
95 ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
97 * clone a fid and add it to writeback_fid
98 * we do it during open time instead of
99 * page dirty time via write_begin/page_mkwrite
100 * because we want write after unlink usecase
103 fid = v9fs_writeback_fid(file->f_path.dentry);
106 mutex_unlock(&v9inode->v_mutex);
109 v9inode->writeback_fid = (void *) fid;
111 mutex_unlock(&v9inode->v_mutex);
112 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
113 v9fs_cache_inode_set_cookie(inode, file);
116 p9_client_clunk(file->private_data);
117 file->private_data = NULL;
122 * v9fs_file_lock - lock a file (or directory)
123 * @filp: file to be locked
125 * @fl: file lock structure
127 * Bugs: this looks like a local only lock, we should extend into 9P
128 * by using open exclusive
131 static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
134 struct inode *inode = file_inode(filp);
136 p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
138 /* No mandatory locks */
139 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
142 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
143 filemap_write_and_wait(inode->i_mapping);
144 invalidate_mapping_pages(&inode->i_data, 0, -1);
150 static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
152 struct p9_flock flock;
156 unsigned char fl_type;
158 fid = filp->private_data;
161 if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
164 res = posix_lock_file_wait(filp, fl);
168 /* convert posix lock to p9 tlock args */
169 memset(&flock, 0, sizeof(flock));
170 /* map the lock type */
171 switch (fl->fl_type) {
173 flock.type = P9_LOCK_TYPE_RDLCK;
176 flock.type = P9_LOCK_TYPE_WRLCK;
179 flock.type = P9_LOCK_TYPE_UNLCK;
182 flock.start = fl->fl_start;
183 if (fl->fl_end == OFFSET_MAX)
186 flock.length = fl->fl_end - fl->fl_start + 1;
187 flock.proc_id = fl->fl_pid;
188 flock.client_id = fid->clnt->name;
190 flock.flags = P9_LOCK_FLAGS_BLOCK;
193 * if its a blocked request and we get P9_LOCK_BLOCKED as the status
194 * for lock request, keep on trying
197 res = p9_client_lock_dotl(fid, &flock, &status);
201 if (status != P9_LOCK_BLOCKED)
203 if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
205 if (schedule_timeout_interruptible(P9_LOCK_TIMEOUT) != 0)
209 /* map 9p status to VFS status */
211 case P9_LOCK_SUCCESS:
214 case P9_LOCK_BLOCKED:
226 * incase server returned error for lock request, revert
229 if (res < 0 && fl->fl_type != F_UNLCK) {
230 fl_type = fl->fl_type;
231 fl->fl_type = F_UNLCK;
232 res = posix_lock_file_wait(filp, fl);
233 fl->fl_type = fl_type;
239 static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
241 struct p9_getlock glock;
245 fid = filp->private_data;
248 posix_test_lock(filp, fl);
250 * if we have a conflicting lock locally, no need to validate
253 if (fl->fl_type != F_UNLCK)
256 /* convert posix lock to p9 tgetlock args */
257 memset(&glock, 0, sizeof(glock));
258 glock.type = P9_LOCK_TYPE_UNLCK;
259 glock.start = fl->fl_start;
260 if (fl->fl_end == OFFSET_MAX)
263 glock.length = fl->fl_end - fl->fl_start + 1;
264 glock.proc_id = fl->fl_pid;
265 glock.client_id = fid->clnt->name;
267 res = p9_client_getlock_dotl(fid, &glock);
270 /* map 9p lock type to os lock type */
271 switch (glock.type) {
272 case P9_LOCK_TYPE_RDLCK:
273 fl->fl_type = F_RDLCK;
275 case P9_LOCK_TYPE_WRLCK:
276 fl->fl_type = F_WRLCK;
278 case P9_LOCK_TYPE_UNLCK:
279 fl->fl_type = F_UNLCK;
282 if (glock.type != P9_LOCK_TYPE_UNLCK) {
283 fl->fl_start = glock.start;
284 if (glock.length == 0)
285 fl->fl_end = OFFSET_MAX;
287 fl->fl_end = glock.start + glock.length - 1;
288 fl->fl_pid = glock.proc_id;
290 kfree(glock.client_id);
295 * v9fs_file_lock_dotl - lock a file (or directory)
296 * @filp: file to be locked
298 * @fl: file lock structure
302 static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
304 struct inode *inode = file_inode(filp);
307 p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
308 filp, cmd, fl, filp);
310 /* No mandatory locks */
311 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
314 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
315 filemap_write_and_wait(inode->i_mapping);
316 invalidate_mapping_pages(&inode->i_data, 0, -1);
319 if (IS_SETLK(cmd) || IS_SETLKW(cmd))
320 ret = v9fs_file_do_lock(filp, cmd, fl);
321 else if (IS_GETLK(cmd))
322 ret = v9fs_file_getlock(filp, fl);
330 * v9fs_file_flock_dotl - lock a file
331 * @filp: file to be locked
333 * @fl: file lock structure
337 static int v9fs_file_flock_dotl(struct file *filp, int cmd,
338 struct file_lock *fl)
340 struct inode *inode = file_inode(filp);
343 p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
344 filp, cmd, fl, filp);
346 /* No mandatory locks */
347 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
350 if (!(fl->fl_flags & FL_FLOCK))
353 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
354 filemap_write_and_wait(inode->i_mapping);
355 invalidate_mapping_pages(&inode->i_data, 0, -1);
357 /* Convert flock to posix lock */
358 fl->fl_flags |= FL_POSIX;
359 fl->fl_flags ^= FL_FLOCK;
361 if (IS_SETLK(cmd) | IS_SETLKW(cmd))
362 ret = v9fs_file_do_lock(filp, cmd, fl);
370 * v9fs_file_read - read from a file
371 * @filp: file pointer to read
372 * @udata: user data buffer to read data into
373 * @count: size of buffer
374 * @offset: offset at which to read data
379 v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
381 struct p9_fid *fid = iocb->ki_filp->private_data;
384 p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n",
385 iov_iter_count(to), iocb->ki_pos);
387 ret = p9_client_read(fid, iocb->ki_pos, to, &err);
396 * v9fs_file_write - write to a file
397 * @filp: file pointer to write
398 * @data: data buffer to write data from
399 * @count: size of buffer
400 * @offset: offset at which to write data
404 v9fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
406 struct file *file = iocb->ki_filp;
411 retval = generic_write_checks(iocb, from);
415 origin = iocb->ki_pos;
416 retval = p9_client_write(file->private_data, iocb->ki_pos, from, &err);
418 struct inode *inode = file_inode(file);
420 unsigned long pg_start, pg_end;
421 pg_start = origin >> PAGE_CACHE_SHIFT;
422 pg_end = (origin + retval - 1) >> PAGE_CACHE_SHIFT;
423 if (inode->i_mapping && inode->i_mapping->nrpages)
424 invalidate_inode_pages2_range(inode->i_mapping,
426 iocb->ki_pos += retval;
427 i_size = i_size_read(inode);
428 if (iocb->ki_pos > i_size) {
429 inode_add_bytes(inode, iocb->ki_pos - i_size);
430 i_size_write(inode, iocb->ki_pos);
437 static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
441 struct inode *inode = filp->f_mapping->host;
442 struct p9_wstat wstat;
445 retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
449 mutex_lock(&inode->i_mutex);
450 p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
452 fid = filp->private_data;
453 v9fs_blank_wstat(&wstat);
455 retval = p9_client_wstat(fid, &wstat);
456 mutex_unlock(&inode->i_mutex);
461 int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
465 struct inode *inode = filp->f_mapping->host;
468 retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
472 mutex_lock(&inode->i_mutex);
473 p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
475 fid = filp->private_data;
477 retval = p9_client_fsync(fid, datasync);
478 mutex_unlock(&inode->i_mutex);
484 v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
489 retval = generic_file_mmap(filp, vma);
491 vma->vm_ops = &v9fs_file_vm_ops;
497 v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
501 struct v9fs_inode *v9inode;
504 inode = file_inode(filp);
505 v9inode = V9FS_I(inode);
506 mutex_lock(&v9inode->v_mutex);
507 if (!v9inode->writeback_fid &&
508 (vma->vm_flags & VM_WRITE)) {
510 * clone a fid and add it to writeback_fid
511 * we do it during mmap instead of
512 * page dirty time via write_begin/page_mkwrite
513 * because we want write after unlink usecase
516 fid = v9fs_writeback_fid(filp->f_path.dentry);
518 retval = PTR_ERR(fid);
519 mutex_unlock(&v9inode->v_mutex);
522 v9inode->writeback_fid = (void *) fid;
524 mutex_unlock(&v9inode->v_mutex);
526 retval = generic_file_mmap(filp, vma);
528 vma->vm_ops = &v9fs_mmap_file_vm_ops;
534 v9fs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
536 struct v9fs_inode *v9inode;
537 struct page *page = vmf->page;
538 struct file *filp = vma->vm_file;
539 struct inode *inode = file_inode(filp);
542 p9_debug(P9_DEBUG_VFS, "page %p fid %lx\n",
543 page, (unsigned long)filp->private_data);
545 /* Update file times before taking page lock */
546 file_update_time(filp);
548 v9inode = V9FS_I(inode);
549 /* make sure the cache has finished storing the page */
550 v9fs_fscache_wait_on_page_write(inode, page);
551 BUG_ON(!v9inode->writeback_fid);
553 if (page->mapping != inode->i_mapping)
555 wait_for_stable_page(page);
557 return VM_FAULT_LOCKED;
560 return VM_FAULT_NOPAGE;
564 * v9fs_mmap_file_read - read from a file
565 * @filp: file pointer to read
566 * @data: user data buffer to read data into
567 * @count: size of buffer
568 * @offset: offset at which to read data
572 v9fs_mmap_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
574 /* TODO: Check if there are dirty pages */
575 return v9fs_file_read_iter(iocb, to);
579 * v9fs_mmap_file_write - write to a file
580 * @filp: file pointer to write
581 * @data: data buffer to write data from
582 * @count: size of buffer
583 * @offset: offset at which to write data
587 v9fs_mmap_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
590 * TODO: invalidate mmaps on filp's inode between
591 * offset and offset+count
593 return v9fs_file_write_iter(iocb, from);
596 static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
600 struct writeback_control wbc = {
601 .nr_to_write = LONG_MAX,
602 .sync_mode = WB_SYNC_ALL,
603 .range_start = vma->vm_pgoff * PAGE_SIZE,
604 /* absolute end, byte at end included */
605 .range_end = vma->vm_pgoff * PAGE_SIZE +
606 (vma->vm_end - vma->vm_start - 1),
610 p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
612 inode = file_inode(vma->vm_file);
614 if (!mapping_cap_writeback_dirty(inode->i_mapping))
618 sync_inode(inode, &wbc);
622 static const struct vm_operations_struct v9fs_file_vm_ops = {
623 .fault = filemap_fault,
624 .map_pages = filemap_map_pages,
625 .page_mkwrite = v9fs_vm_page_mkwrite,
628 static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
629 .close = v9fs_mmap_vm_close,
630 .fault = filemap_fault,
631 .map_pages = filemap_map_pages,
632 .page_mkwrite = v9fs_vm_page_mkwrite,
636 const struct file_operations v9fs_cached_file_operations = {
637 .llseek = generic_file_llseek,
638 .read_iter = generic_file_read_iter,
639 .write_iter = generic_file_write_iter,
640 .open = v9fs_file_open,
641 .release = v9fs_dir_release,
642 .lock = v9fs_file_lock,
643 .mmap = v9fs_file_mmap,
644 .fsync = v9fs_file_fsync,
647 const struct file_operations v9fs_cached_file_operations_dotl = {
648 .llseek = generic_file_llseek,
649 .read_iter = generic_file_read_iter,
650 .write_iter = generic_file_write_iter,
651 .open = v9fs_file_open,
652 .release = v9fs_dir_release,
653 .lock = v9fs_file_lock_dotl,
654 .flock = v9fs_file_flock_dotl,
655 .mmap = v9fs_file_mmap,
656 .fsync = v9fs_file_fsync_dotl,
659 const struct file_operations v9fs_file_operations = {
660 .llseek = generic_file_llseek,
661 .read_iter = v9fs_file_read_iter,
662 .write_iter = v9fs_file_write_iter,
663 .open = v9fs_file_open,
664 .release = v9fs_dir_release,
665 .lock = v9fs_file_lock,
666 .mmap = generic_file_readonly_mmap,
667 .fsync = v9fs_file_fsync,
670 const struct file_operations v9fs_file_operations_dotl = {
671 .llseek = generic_file_llseek,
672 .read_iter = v9fs_file_read_iter,
673 .write_iter = v9fs_file_write_iter,
674 .open = v9fs_file_open,
675 .release = v9fs_dir_release,
676 .lock = v9fs_file_lock_dotl,
677 .flock = v9fs_file_flock_dotl,
678 .mmap = generic_file_readonly_mmap,
679 .fsync = v9fs_file_fsync_dotl,
682 const struct file_operations v9fs_mmap_file_operations = {
683 .llseek = generic_file_llseek,
684 .read_iter = v9fs_mmap_file_read_iter,
685 .write_iter = v9fs_mmap_file_write_iter,
686 .open = v9fs_file_open,
687 .release = v9fs_dir_release,
688 .lock = v9fs_file_lock,
689 .mmap = v9fs_mmap_file_mmap,
690 .fsync = v9fs_file_fsync,
693 const struct file_operations v9fs_mmap_file_operations_dotl = {
694 .llseek = generic_file_llseek,
695 .read_iter = v9fs_mmap_file_read_iter,
696 .write_iter = v9fs_mmap_file_write_iter,
697 .open = v9fs_file_open,
698 .release = v9fs_dir_release,
699 .lock = v9fs_file_lock_dotl,
700 .flock = v9fs_file_flock_dotl,
701 .mmap = v9fs_mmap_file_mmap,
702 .fsync = v9fs_file_fsync_dotl,