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 <net/9p/9p.h>
40 #include <net/9p/client.h>
47 static const struct vm_operations_struct v9fs_file_vm_ops;
50 * v9fs_file_open - open a file (or directory)
51 * @inode: inode to be opened
52 * @file: file being opened
56 int v9fs_file_open(struct inode *inode, struct file *file)
59 struct v9fs_inode *v9inode;
60 struct v9fs_session_info *v9ses;
64 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
65 v9inode = V9FS_I(inode);
66 v9ses = v9fs_inode2v9ses(inode);
67 if (v9fs_proto_dotl(v9ses))
68 omode = file->f_flags;
70 omode = v9fs_uflags2omode(file->f_flags,
71 v9fs_proto_dotu(v9ses));
72 fid = file->private_data;
74 fid = v9fs_fid_clone(file->f_path.dentry);
78 err = p9_client_open(fid, omode);
83 if (file->f_flags & O_TRUNC) {
84 i_size_write(inode, 0);
87 if ((file->f_flags & O_APPEND) &&
88 (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
89 generic_file_llseek(file, 0, SEEK_END);
92 file->private_data = fid;
93 mutex_lock(&v9inode->v_mutex);
94 if (v9ses->cache && !v9inode->writeback_fid) {
96 * clone a fid and add it to writeback_fid
97 * we do it during open time instead of
98 * page dirty time via write_begin/page_mkwrite
99 * because we want write after unlink usecase
102 fid = v9fs_writeback_fid(file->f_path.dentry);
105 mutex_unlock(&v9inode->v_mutex);
108 v9inode->writeback_fid = (void *) fid;
110 mutex_unlock(&v9inode->v_mutex);
111 #ifdef CONFIG_9P_FSCACHE
113 v9fs_cache_inode_set_cookie(inode, file);
117 p9_client_clunk(file->private_data);
118 file->private_data = NULL;
123 * v9fs_file_lock - lock a file (or directory)
124 * @filp: file to be locked
126 * @fl: file lock structure
128 * Bugs: this looks like a local only lock, we should extend into 9P
129 * by using open exclusive
132 static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
135 struct inode *inode = filp->f_path.dentry->d_inode;
137 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
139 /* No mandatory locks */
140 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
143 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
144 filemap_write_and_wait(inode->i_mapping);
145 invalidate_mapping_pages(&inode->i_data, 0, -1);
151 static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
153 struct p9_flock flock;
157 unsigned char fl_type;
159 fid = filp->private_data;
162 if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
165 res = posix_lock_file_wait(filp, fl);
169 /* convert posix lock to p9 tlock args */
170 memset(&flock, 0, sizeof(flock));
171 flock.type = fl->fl_type;
172 flock.start = fl->fl_start;
173 if (fl->fl_end == OFFSET_MAX)
176 flock.length = fl->fl_end - fl->fl_start + 1;
177 flock.proc_id = fl->fl_pid;
178 flock.client_id = utsname()->nodename;
180 flock.flags = P9_LOCK_FLAGS_BLOCK;
183 * if its a blocked request and we get P9_LOCK_BLOCKED as the status
184 * for lock request, keep on trying
187 res = p9_client_lock_dotl(fid, &flock, &status);
191 if (status != P9_LOCK_BLOCKED)
193 if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
195 schedule_timeout_interruptible(P9_LOCK_TIMEOUT);
198 /* map 9p status to VFS status */
200 case P9_LOCK_SUCCESS:
203 case P9_LOCK_BLOCKED:
215 * incase server returned error for lock request, revert
218 if (res < 0 && fl->fl_type != F_UNLCK) {
219 fl_type = fl->fl_type;
220 fl->fl_type = F_UNLCK;
221 res = posix_lock_file_wait(filp, fl);
222 fl->fl_type = fl_type;
228 static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
230 struct p9_getlock glock;
234 fid = filp->private_data;
237 posix_test_lock(filp, fl);
239 * if we have a conflicting lock locally, no need to validate
242 if (fl->fl_type != F_UNLCK)
245 /* convert posix lock to p9 tgetlock args */
246 memset(&glock, 0, sizeof(glock));
247 glock.type = fl->fl_type;
248 glock.start = fl->fl_start;
249 if (fl->fl_end == OFFSET_MAX)
252 glock.length = fl->fl_end - fl->fl_start + 1;
253 glock.proc_id = fl->fl_pid;
254 glock.client_id = utsname()->nodename;
256 res = p9_client_getlock_dotl(fid, &glock);
259 if (glock.type != F_UNLCK) {
260 fl->fl_type = glock.type;
261 fl->fl_start = glock.start;
262 if (glock.length == 0)
263 fl->fl_end = OFFSET_MAX;
265 fl->fl_end = glock.start + glock.length - 1;
266 fl->fl_pid = glock.proc_id;
268 fl->fl_type = F_UNLCK;
274 * v9fs_file_lock_dotl - lock a file (or directory)
275 * @filp: file to be locked
277 * @fl: file lock structure
281 static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
283 struct inode *inode = filp->f_path.dentry->d_inode;
286 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n", filp,
287 cmd, fl, filp->f_path.dentry->d_name.name);
289 /* No mandatory locks */
290 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
293 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
294 filemap_write_and_wait(inode->i_mapping);
295 invalidate_mapping_pages(&inode->i_data, 0, -1);
298 if (IS_SETLK(cmd) || IS_SETLKW(cmd))
299 ret = v9fs_file_do_lock(filp, cmd, fl);
300 else if (IS_GETLK(cmd))
301 ret = v9fs_file_getlock(filp, fl);
309 * v9fs_file_flock_dotl - lock a file
310 * @filp: file to be locked
312 * @fl: file lock structure
316 static int v9fs_file_flock_dotl(struct file *filp, int cmd,
317 struct file_lock *fl)
319 struct inode *inode = filp->f_path.dentry->d_inode;
322 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n", filp,
323 cmd, fl, filp->f_path.dentry->d_name.name);
325 /* No mandatory locks */
326 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
329 if (!(fl->fl_flags & FL_FLOCK))
332 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
333 filemap_write_and_wait(inode->i_mapping);
334 invalidate_mapping_pages(&inode->i_data, 0, -1);
336 /* Convert flock to posix lock */
337 fl->fl_owner = (fl_owner_t)filp;
339 fl->fl_end = OFFSET_MAX;
340 fl->fl_flags |= FL_POSIX;
341 fl->fl_flags ^= FL_FLOCK;
343 if (IS_SETLK(cmd) | IS_SETLKW(cmd))
344 ret = v9fs_file_do_lock(filp, cmd, fl);
352 * v9fs_fid_readn - read from a fid
354 * @data: data buffer to read data into
355 * @udata: user data buffer to read data into
356 * @count: size of buffer
357 * @offset: offset at which to read data
361 v9fs_fid_readn(struct p9_fid *fid, char *data, char __user *udata, u32 count,
366 P9_DPRINTK(P9_DEBUG_VFS, "fid %d offset %llu count %d\n", fid->fid,
367 (long long unsigned) offset, count);
370 size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
372 n = p9_client_read(fid, data, udata, offset, count);
384 } while (count > 0 && n == size);
393 * v9fs_file_readn - read from a file
394 * @filp: file pointer to read
395 * @data: data buffer to read data into
396 * @udata: user data buffer to read data into
397 * @count: size of buffer
398 * @offset: offset at which to read data
402 v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
405 return v9fs_fid_readn(filp->private_data, data, udata, count, offset);
409 * v9fs_file_read - read from a file
410 * @filp: file pointer to read
411 * @udata: user data buffer to read data into
412 * @count: size of buffer
413 * @offset: offset at which to read data
418 v9fs_file_read(struct file *filp, char __user *udata, size_t count,
425 P9_DPRINTK(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
426 fid = filp->private_data;
428 size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
430 ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
432 ret = p9_client_read(fid, NULL, udata, *offset, count);
441 v9fs_file_write_internal(struct inode *inode, struct p9_fid *fid,
442 const char __user *data, size_t count,
443 loff_t *offset, int invalidate)
448 struct p9_client *clnt;
449 loff_t origin = *offset;
450 unsigned long pg_start, pg_end;
452 P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data,
453 (int)count, (int)*offset);
457 n = p9_client_write(fid, NULL, data+total, origin+total, count);
464 if (invalidate && (total > 0)) {
465 pg_start = origin >> PAGE_CACHE_SHIFT;
466 pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
467 if (inode->i_mapping && inode->i_mapping->nrpages)
468 invalidate_inode_pages2_range(inode->i_mapping,
471 i_size = i_size_read(inode);
472 if (*offset > i_size) {
473 inode_add_bytes(inode, *offset - i_size);
474 i_size_write(inode, *offset);
484 * v9fs_file_write - write to a file
485 * @filp: file pointer to write
486 * @data: data buffer to write data from
487 * @count: size of buffer
488 * @offset: offset at which to write data
492 v9fs_file_write(struct file *filp, const char __user * data,
493 size_t count, loff_t *offset)
496 loff_t origin = *offset;
499 retval = generic_write_checks(filp, &origin, &count, 0);
504 if ((ssize_t) count < 0)
510 return v9fs_file_write_internal(filp->f_path.dentry->d_inode,
512 data, count, offset, 1);
518 static int v9fs_file_fsync(struct file *filp, int datasync)
521 struct p9_wstat wstat;
524 P9_DPRINTK(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
526 fid = filp->private_data;
527 v9fs_blank_wstat(&wstat);
529 retval = p9_client_wstat(fid, &wstat);
533 int v9fs_file_fsync_dotl(struct file *filp, int datasync)
538 P9_DPRINTK(P9_DEBUG_VFS, "v9fs_file_fsync_dotl: filp %p datasync %x\n",
541 fid = filp->private_data;
543 retval = p9_client_fsync(fid, datasync);
548 v9fs_file_mmap(struct file *file, struct vm_area_struct *vma)
552 retval = generic_file_mmap(file, vma);
554 vma->vm_ops = &v9fs_file_vm_ops;
560 v9fs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
562 struct v9fs_inode *v9inode;
563 struct page *page = vmf->page;
564 struct file *filp = vma->vm_file;
565 struct inode *inode = filp->f_path.dentry->d_inode;
568 P9_DPRINTK(P9_DEBUG_VFS, "page %p fid %lx\n",
569 page, (unsigned long)filp->private_data);
571 v9inode = V9FS_I(inode);
572 /* make sure the cache has finished storing the page */
573 v9fs_fscache_wait_on_page_write(inode, page);
574 BUG_ON(!v9inode->writeback_fid);
576 if (page->mapping != inode->i_mapping)
579 return VM_FAULT_LOCKED;
582 return VM_FAULT_NOPAGE;
586 v9fs_direct_read(struct file *filp, char __user *udata, size_t count,
591 struct address_space *mapping;
594 mapping = filp->f_mapping;
595 inode = mapping->host;
598 size = i_size_read(inode);
600 filemap_write_and_wait_range(mapping, offset,
603 return v9fs_file_read(filp, udata, count, offsetp);
607 * v9fs_cached_file_read - read from a file
608 * @filp: file pointer to read
609 * @udata: user data buffer to read data into
610 * @count: size of buffer
611 * @offset: offset at which to read data
615 v9fs_cached_file_read(struct file *filp, char __user *data, size_t count,
618 if (filp->f_flags & O_DIRECT)
619 return v9fs_direct_read(filp, data, count, offset);
620 return do_sync_read(filp, data, count, offset);
624 v9fs_direct_write(struct file *filp, const char __user * data,
625 size_t count, loff_t *offsetp)
630 struct address_space *mapping;
633 mapping = filp->f_mapping;
634 inode = mapping->host;
638 mutex_lock(&inode->i_mutex);
639 retval = filemap_write_and_wait_range(mapping, offset,
644 * After a write we want buffered reads to be sure to go to disk to get
645 * the new data. We invalidate clean cached page from the region we're
646 * about to write. We do this *before* the write so that if we fail
647 * here we fall back to buffered write
649 if (mapping->nrpages) {
650 pgoff_t pg_start = offset >> PAGE_CACHE_SHIFT;
651 pgoff_t pg_end = (offset + count - 1) >> PAGE_CACHE_SHIFT;
653 retval = invalidate_inode_pages2_range(mapping,
656 * If a page can not be invalidated, fall back
660 if (retval == -EBUSY)
665 retval = v9fs_file_write(filp, data, count, offsetp);
667 mutex_unlock(&inode->i_mutex);
671 mutex_unlock(&inode->i_mutex);
672 return do_sync_write(filp, data, count, offsetp);
676 * v9fs_cached_file_write - write to a file
677 * @filp: file pointer to write
678 * @data: data buffer to write data from
679 * @count: size of buffer
680 * @offset: offset at which to write data
684 v9fs_cached_file_write(struct file *filp, const char __user * data,
685 size_t count, loff_t *offset)
688 if (filp->f_flags & O_DIRECT)
689 return v9fs_direct_write(filp, data, count, offset);
690 return do_sync_write(filp, data, count, offset);
693 static const struct vm_operations_struct v9fs_file_vm_ops = {
694 .fault = filemap_fault,
695 .page_mkwrite = v9fs_vm_page_mkwrite,
699 const struct file_operations v9fs_cached_file_operations = {
700 .llseek = generic_file_llseek,
701 .read = v9fs_cached_file_read,
702 .write = v9fs_cached_file_write,
703 .aio_read = generic_file_aio_read,
704 .aio_write = generic_file_aio_write,
705 .open = v9fs_file_open,
706 .release = v9fs_dir_release,
707 .lock = v9fs_file_lock,
708 .mmap = v9fs_file_mmap,
709 .fsync = v9fs_file_fsync,
712 const struct file_operations v9fs_cached_file_operations_dotl = {
713 .llseek = generic_file_llseek,
714 .read = v9fs_cached_file_read,
715 .write = v9fs_cached_file_write,
716 .aio_read = generic_file_aio_read,
717 .aio_write = generic_file_aio_write,
718 .open = v9fs_file_open,
719 .release = v9fs_dir_release,
720 .lock = v9fs_file_lock_dotl,
721 .flock = v9fs_file_flock_dotl,
722 .mmap = v9fs_file_mmap,
723 .fsync = v9fs_file_fsync_dotl,
726 const struct file_operations v9fs_file_operations = {
727 .llseek = generic_file_llseek,
728 .read = v9fs_file_read,
729 .write = v9fs_file_write,
730 .open = v9fs_file_open,
731 .release = v9fs_dir_release,
732 .lock = v9fs_file_lock,
733 .mmap = generic_file_readonly_mmap,
734 .fsync = v9fs_file_fsync,
737 const struct file_operations v9fs_file_operations_dotl = {
738 .llseek = generic_file_llseek,
739 .read = v9fs_file_read,
740 .write = v9fs_file_write,
741 .open = v9fs_file_open,
742 .release = v9fs_dir_release,
743 .lock = v9fs_file_lock_dotl,
744 .flock = v9fs_file_flock_dotl,
745 .mmap = generic_file_readonly_mmap,
746 .fsync = v9fs_file_fsync_dotl,