2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu>
5 This program can be distributed under the terms of the GNU GPL.
11 #include <linux/pagemap.h>
12 #include <linux/slab.h>
13 #include <linux/kernel.h>
15 static struct file_operations fuse_direct_io_file_operations
;
17 static int fuse_send_open(struct inode
*inode
, struct file
*file
, int isdir
,
18 struct fuse_open_out
*outargp
)
20 struct fuse_conn
*fc
= get_fuse_conn(inode
);
21 struct fuse_open_in inarg
;
25 req
= fuse_get_request(fc
);
29 memset(&inarg
, 0, sizeof(inarg
));
30 inarg
.flags
= file
->f_flags
& ~(O_CREAT
| O_EXCL
| O_NOCTTY
| O_TRUNC
);
31 req
->in
.h
.opcode
= isdir
? FUSE_OPENDIR
: FUSE_OPEN
;
32 req
->in
.h
.nodeid
= get_node_id(inode
);
35 req
->in
.args
[0].size
= sizeof(inarg
);
36 req
->in
.args
[0].value
= &inarg
;
38 req
->out
.args
[0].size
= sizeof(*outargp
);
39 req
->out
.args
[0].value
= outargp
;
40 request_send(fc
, req
);
41 err
= req
->out
.h
.error
;
42 fuse_put_request(fc
, req
);
47 struct fuse_file
*fuse_file_alloc(void)
50 ff
= kmalloc(sizeof(struct fuse_file
), GFP_KERNEL
);
52 ff
->release_req
= fuse_request_alloc();
53 if (!ff
->release_req
) {
61 void fuse_file_free(struct fuse_file
*ff
)
63 fuse_request_free(ff
->release_req
);
67 void fuse_finish_open(struct inode
*inode
, struct file
*file
,
68 struct fuse_file
*ff
, struct fuse_open_out
*outarg
)
70 if (outarg
->open_flags
& FOPEN_DIRECT_IO
)
71 file
->f_op
= &fuse_direct_io_file_operations
;
72 if (!(outarg
->open_flags
& FOPEN_KEEP_CACHE
))
73 invalidate_inode_pages(inode
->i_mapping
);
75 file
->private_data
= ff
;
78 int fuse_open_common(struct inode
*inode
, struct file
*file
, int isdir
)
80 struct fuse_open_out outarg
;
84 /* VFS checks this, but only _after_ ->open() */
85 if (file
->f_flags
& O_DIRECT
)
88 err
= generic_file_open(inode
, file
);
92 /* If opening the root node, no lookup has been performed on
93 it, so the attributes must be refreshed */
94 if (get_node_id(inode
) == FUSE_ROOT_ID
) {
95 err
= fuse_do_getattr(inode
);
100 ff
= fuse_file_alloc();
104 err
= fuse_send_open(inode
, file
, isdir
, &outarg
);
109 outarg
.open_flags
&= ~FOPEN_DIRECT_IO
;
110 fuse_finish_open(inode
, file
, ff
, &outarg
);
116 void fuse_send_release(struct fuse_conn
*fc
, struct fuse_file
*ff
,
117 u64 nodeid
, struct inode
*inode
, int flags
, int isdir
)
119 struct fuse_req
* req
= ff
->release_req
;
120 struct fuse_release_in
*inarg
= &req
->misc
.release_in
;
123 inarg
->flags
= flags
;
124 req
->in
.h
.opcode
= isdir
? FUSE_RELEASEDIR
: FUSE_RELEASE
;
125 req
->in
.h
.nodeid
= nodeid
;
128 req
->in
.args
[0].size
= sizeof(struct fuse_release_in
);
129 req
->in
.args
[0].value
= inarg
;
130 request_send_background(fc
, req
);
134 int fuse_release_common(struct inode
*inode
, struct file
*file
, int isdir
)
136 struct fuse_file
*ff
= file
->private_data
;
138 struct fuse_conn
*fc
= get_fuse_conn(inode
);
139 u64 nodeid
= get_node_id(inode
);
140 fuse_send_release(fc
, ff
, nodeid
, inode
, file
->f_flags
, isdir
);
143 /* Return value is ignored by VFS */
147 static int fuse_open(struct inode
*inode
, struct file
*file
)
149 return fuse_open_common(inode
, file
, 0);
152 static int fuse_release(struct inode
*inode
, struct file
*file
)
154 return fuse_release_common(inode
, file
, 0);
157 static int fuse_flush(struct file
*file
)
159 struct inode
*inode
= file
->f_dentry
->d_inode
;
160 struct fuse_conn
*fc
= get_fuse_conn(inode
);
161 struct fuse_file
*ff
= file
->private_data
;
162 struct fuse_req
*req
;
163 struct fuse_flush_in inarg
;
166 if (is_bad_inode(inode
))
172 req
= fuse_get_request(fc
);
176 memset(&inarg
, 0, sizeof(inarg
));
178 req
->in
.h
.opcode
= FUSE_FLUSH
;
179 req
->in
.h
.nodeid
= get_node_id(inode
);
183 req
->in
.args
[0].size
= sizeof(inarg
);
184 req
->in
.args
[0].value
= &inarg
;
185 request_send(fc
, req
);
186 err
= req
->out
.h
.error
;
187 fuse_put_request(fc
, req
);
188 if (err
== -ENOSYS
) {
195 int fuse_fsync_common(struct file
*file
, struct dentry
*de
, int datasync
,
198 struct inode
*inode
= de
->d_inode
;
199 struct fuse_conn
*fc
= get_fuse_conn(inode
);
200 struct fuse_file
*ff
= file
->private_data
;
201 struct fuse_req
*req
;
202 struct fuse_fsync_in inarg
;
205 if (is_bad_inode(inode
))
208 if ((!isdir
&& fc
->no_fsync
) || (isdir
&& fc
->no_fsyncdir
))
211 req
= fuse_get_request(fc
);
215 memset(&inarg
, 0, sizeof(inarg
));
217 inarg
.fsync_flags
= datasync
? 1 : 0;
218 req
->in
.h
.opcode
= isdir
? FUSE_FSYNCDIR
: FUSE_FSYNC
;
219 req
->in
.h
.nodeid
= get_node_id(inode
);
223 req
->in
.args
[0].size
= sizeof(inarg
);
224 req
->in
.args
[0].value
= &inarg
;
225 request_send(fc
, req
);
226 err
= req
->out
.h
.error
;
227 fuse_put_request(fc
, req
);
228 if (err
== -ENOSYS
) {
238 static int fuse_fsync(struct file
*file
, struct dentry
*de
, int datasync
)
240 return fuse_fsync_common(file
, de
, datasync
, 0);
243 size_t fuse_send_read_common(struct fuse_req
*req
, struct file
*file
,
244 struct inode
*inode
, loff_t pos
, size_t count
,
247 struct fuse_conn
*fc
= get_fuse_conn(inode
);
248 struct fuse_file
*ff
= file
->private_data
;
249 struct fuse_read_in inarg
;
251 memset(&inarg
, 0, sizeof(struct fuse_read_in
));
255 req
->in
.h
.opcode
= isdir
? FUSE_READDIR
: FUSE_READ
;
256 req
->in
.h
.nodeid
= get_node_id(inode
);
260 req
->in
.args
[0].size
= sizeof(struct fuse_read_in
);
261 req
->in
.args
[0].value
= &inarg
;
262 req
->out
.argpages
= 1;
264 req
->out
.numargs
= 1;
265 req
->out
.args
[0].size
= count
;
266 request_send(fc
, req
);
267 return req
->out
.args
[0].size
;
270 static inline size_t fuse_send_read(struct fuse_req
*req
, struct file
*file
,
271 struct inode
*inode
, loff_t pos
,
274 return fuse_send_read_common(req
, file
, inode
, pos
, count
, 0);
277 static int fuse_readpage(struct file
*file
, struct page
*page
)
279 struct inode
*inode
= page
->mapping
->host
;
280 struct fuse_conn
*fc
= get_fuse_conn(inode
);
281 struct fuse_req
*req
;
285 if (is_bad_inode(inode
))
289 req
= fuse_get_request(fc
);
293 req
->out
.page_zeroing
= 1;
295 req
->pages
[0] = page
;
296 fuse_send_read(req
, file
, inode
, page_offset(page
), PAGE_CACHE_SIZE
);
297 err
= req
->out
.h
.error
;
298 fuse_put_request(fc
, req
);
300 SetPageUptodate(page
);
301 fuse_invalidate_attr(inode
); /* atime changed */
307 static int fuse_send_readpages(struct fuse_req
*req
, struct file
*file
,
310 loff_t pos
= page_offset(req
->pages
[0]);
311 size_t count
= req
->num_pages
<< PAGE_CACHE_SHIFT
;
313 req
->out
.page_zeroing
= 1;
314 fuse_send_read(req
, file
, inode
, pos
, count
);
315 for (i
= 0; i
< req
->num_pages
; i
++) {
316 struct page
*page
= req
->pages
[i
];
317 if (!req
->out
.h
.error
)
318 SetPageUptodate(page
);
321 return req
->out
.h
.error
;
324 struct fuse_readpages_data
{
325 struct fuse_req
*req
;
330 static int fuse_readpages_fill(void *_data
, struct page
*page
)
332 struct fuse_readpages_data
*data
= _data
;
333 struct fuse_req
*req
= data
->req
;
334 struct inode
*inode
= data
->inode
;
335 struct fuse_conn
*fc
= get_fuse_conn(inode
);
337 if (req
->num_pages
&&
338 (req
->num_pages
== FUSE_MAX_PAGES_PER_REQ
||
339 (req
->num_pages
+ 1) * PAGE_CACHE_SIZE
> fc
->max_read
||
340 req
->pages
[req
->num_pages
- 1]->index
+ 1 != page
->index
)) {
341 int err
= fuse_send_readpages(req
, data
->file
, inode
);
346 fuse_reset_request(req
);
348 req
->pages
[req
->num_pages
] = page
;
353 static int fuse_readpages(struct file
*file
, struct address_space
*mapping
,
354 struct list_head
*pages
, unsigned nr_pages
)
356 struct inode
*inode
= mapping
->host
;
357 struct fuse_conn
*fc
= get_fuse_conn(inode
);
358 struct fuse_readpages_data data
;
361 if (is_bad_inode(inode
))
366 data
.req
= fuse_get_request(fc
);
370 err
= read_cache_pages(mapping
, pages
, fuse_readpages_fill
, &data
);
371 if (!err
&& data
.req
->num_pages
)
372 err
= fuse_send_readpages(data
.req
, file
, inode
);
373 fuse_put_request(fc
, data
.req
);
374 fuse_invalidate_attr(inode
); /* atime changed */
378 static size_t fuse_send_write(struct fuse_req
*req
, struct file
*file
,
379 struct inode
*inode
, loff_t pos
, size_t count
)
381 struct fuse_conn
*fc
= get_fuse_conn(inode
);
382 struct fuse_file
*ff
= file
->private_data
;
383 struct fuse_write_in inarg
;
384 struct fuse_write_out outarg
;
386 memset(&inarg
, 0, sizeof(struct fuse_write_in
));
390 req
->in
.h
.opcode
= FUSE_WRITE
;
391 req
->in
.h
.nodeid
= get_node_id(inode
);
394 req
->in
.argpages
= 1;
396 req
->in
.args
[0].size
= sizeof(struct fuse_write_in
);
397 req
->in
.args
[0].value
= &inarg
;
398 req
->in
.args
[1].size
= count
;
399 req
->out
.numargs
= 1;
400 req
->out
.args
[0].size
= sizeof(struct fuse_write_out
);
401 req
->out
.args
[0].value
= &outarg
;
402 request_send(fc
, req
);
406 static int fuse_prepare_write(struct file
*file
, struct page
*page
,
407 unsigned offset
, unsigned to
)
413 static int fuse_commit_write(struct file
*file
, struct page
*page
,
414 unsigned offset
, unsigned to
)
418 unsigned count
= to
- offset
;
419 struct inode
*inode
= page
->mapping
->host
;
420 struct fuse_conn
*fc
= get_fuse_conn(inode
);
421 loff_t pos
= page_offset(page
) + offset
;
422 struct fuse_req
*req
;
424 if (is_bad_inode(inode
))
427 req
= fuse_get_request(fc
);
432 req
->pages
[0] = page
;
433 req
->page_offset
= offset
;
434 nres
= fuse_send_write(req
, file
, inode
, pos
, count
);
435 err
= req
->out
.h
.error
;
436 fuse_put_request(fc
, req
);
437 if (!err
&& nres
!= count
)
441 if (pos
> i_size_read(inode
))
442 i_size_write(inode
, pos
);
444 if (offset
== 0 && to
== PAGE_CACHE_SIZE
) {
445 clear_page_dirty(page
);
446 SetPageUptodate(page
);
449 fuse_invalidate_attr(inode
);
453 static void fuse_release_user_pages(struct fuse_req
*req
, int write
)
457 for (i
= 0; i
< req
->num_pages
; i
++) {
458 struct page
*page
= req
->pages
[i
];
460 set_page_dirty_lock(page
);
465 static int fuse_get_user_pages(struct fuse_req
*req
, const char __user
*buf
,
466 unsigned nbytes
, int write
)
468 unsigned long user_addr
= (unsigned long) buf
;
469 unsigned offset
= user_addr
& ~PAGE_MASK
;
472 /* This doesn't work with nfsd */
476 nbytes
= min(nbytes
, (unsigned) FUSE_MAX_PAGES_PER_REQ
<< PAGE_SHIFT
);
477 npages
= (nbytes
+ offset
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
478 npages
= min(max(npages
, 1), FUSE_MAX_PAGES_PER_REQ
);
479 down_read(¤t
->mm
->mmap_sem
);
480 npages
= get_user_pages(current
, current
->mm
, user_addr
, npages
, write
,
481 0, req
->pages
, NULL
);
482 up_read(¤t
->mm
->mmap_sem
);
486 req
->num_pages
= npages
;
487 req
->page_offset
= offset
;
491 static ssize_t
fuse_direct_io(struct file
*file
, const char __user
*buf
,
492 size_t count
, loff_t
*ppos
, int write
)
494 struct inode
*inode
= file
->f_dentry
->d_inode
;
495 struct fuse_conn
*fc
= get_fuse_conn(inode
);
496 size_t nmax
= write
? fc
->max_write
: fc
->max_read
;
499 struct fuse_req
*req
;
501 if (is_bad_inode(inode
))
504 req
= fuse_get_request(fc
);
510 size_t nbytes
= min(count
, nmax
);
511 int err
= fuse_get_user_pages(req
, buf
, nbytes
, !write
);
516 nbytes
= (req
->num_pages
<< PAGE_SHIFT
) - req
->page_offset
;
517 nbytes
= min(count
, nbytes
);
519 nres
= fuse_send_write(req
, file
, inode
, pos
, nbytes
);
521 nres
= fuse_send_read(req
, file
, inode
, pos
, nbytes
);
522 fuse_release_user_pages(req
, !write
);
523 if (req
->out
.h
.error
) {
525 res
= req
->out
.h
.error
;
527 } else if (nres
> nbytes
) {
538 fuse_reset_request(req
);
540 fuse_put_request(fc
, req
);
542 if (write
&& pos
> i_size_read(inode
))
543 i_size_write(inode
, pos
);
546 fuse_invalidate_attr(inode
);
551 static ssize_t
fuse_direct_read(struct file
*file
, char __user
*buf
,
552 size_t count
, loff_t
*ppos
)
554 return fuse_direct_io(file
, buf
, count
, ppos
, 0);
557 static ssize_t
fuse_direct_write(struct file
*file
, const char __user
*buf
,
558 size_t count
, loff_t
*ppos
)
560 struct inode
*inode
= file
->f_dentry
->d_inode
;
562 /* Don't allow parallel writes to the same file */
563 mutex_lock(&inode
->i_mutex
);
564 res
= fuse_direct_io(file
, buf
, count
, ppos
, 1);
565 mutex_unlock(&inode
->i_mutex
);
569 static int fuse_file_mmap(struct file
*file
, struct vm_area_struct
*vma
)
571 if ((vma
->vm_flags
& VM_SHARED
)) {
572 if ((vma
->vm_flags
& VM_WRITE
))
575 vma
->vm_flags
&= ~VM_MAYWRITE
;
577 return generic_file_mmap(file
, vma
);
580 static int fuse_set_page_dirty(struct page
*page
)
582 printk("fuse_set_page_dirty: should not happen\n");
587 static struct file_operations fuse_file_operations
= {
588 .llseek
= generic_file_llseek
,
589 .read
= generic_file_read
,
590 .write
= generic_file_write
,
591 .mmap
= fuse_file_mmap
,
594 .release
= fuse_release
,
596 .sendfile
= generic_file_sendfile
,
599 static struct file_operations fuse_direct_io_file_operations
= {
600 .llseek
= generic_file_llseek
,
601 .read
= fuse_direct_read
,
602 .write
= fuse_direct_write
,
605 .release
= fuse_release
,
607 /* no mmap and sendfile */
610 static struct address_space_operations fuse_file_aops
= {
611 .readpage
= fuse_readpage
,
612 .prepare_write
= fuse_prepare_write
,
613 .commit_write
= fuse_commit_write
,
614 .readpages
= fuse_readpages
,
615 .set_page_dirty
= fuse_set_page_dirty
,
618 void fuse_init_file_inode(struct inode
*inode
)
620 inode
->i_fop
= &fuse_file_operations
;
621 inode
->i_data
.a_ops
= &fuse_file_aops
;