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 /* Special case for failed iget in CREATE */
117 static void fuse_release_end(struct fuse_conn
*fc
, struct fuse_req
*req
)
119 u64 nodeid
= req
->in
.h
.nodeid
;
120 fuse_reset_request(req
);
121 fuse_send_forget(fc
, req
, nodeid
, 1);
124 void fuse_send_release(struct fuse_conn
*fc
, struct fuse_file
*ff
,
125 u64 nodeid
, struct inode
*inode
, int flags
, int isdir
)
127 struct fuse_req
* req
= ff
->release_req
;
128 struct fuse_release_in
*inarg
= &req
->misc
.release_in
;
131 inarg
->flags
= flags
;
132 req
->in
.h
.opcode
= isdir
? FUSE_RELEASEDIR
: FUSE_RELEASE
;
133 req
->in
.h
.nodeid
= nodeid
;
136 req
->in
.args
[0].size
= sizeof(struct fuse_release_in
);
137 req
->in
.args
[0].value
= inarg
;
138 request_send_background(fc
, req
);
140 req
->end
= fuse_release_end
;
144 int fuse_release_common(struct inode
*inode
, struct file
*file
, int isdir
)
146 struct fuse_file
*ff
= file
->private_data
;
148 struct fuse_conn
*fc
= get_fuse_conn(inode
);
149 u64 nodeid
= get_node_id(inode
);
150 fuse_send_release(fc
, ff
, nodeid
, inode
, file
->f_flags
, isdir
);
153 /* Return value is ignored by VFS */
157 static int fuse_open(struct inode
*inode
, struct file
*file
)
159 return fuse_open_common(inode
, file
, 0);
162 static int fuse_release(struct inode
*inode
, struct file
*file
)
164 return fuse_release_common(inode
, file
, 0);
167 static int fuse_flush(struct file
*file
)
169 struct inode
*inode
= file
->f_dentry
->d_inode
;
170 struct fuse_conn
*fc
= get_fuse_conn(inode
);
171 struct fuse_file
*ff
= file
->private_data
;
172 struct fuse_req
*req
;
173 struct fuse_flush_in inarg
;
176 if (is_bad_inode(inode
))
182 req
= fuse_get_request(fc
);
186 memset(&inarg
, 0, sizeof(inarg
));
188 req
->in
.h
.opcode
= FUSE_FLUSH
;
189 req
->in
.h
.nodeid
= get_node_id(inode
);
193 req
->in
.args
[0].size
= sizeof(inarg
);
194 req
->in
.args
[0].value
= &inarg
;
195 request_send(fc
, req
);
196 err
= req
->out
.h
.error
;
197 fuse_put_request(fc
, req
);
198 if (err
== -ENOSYS
) {
205 int fuse_fsync_common(struct file
*file
, struct dentry
*de
, int datasync
,
208 struct inode
*inode
= de
->d_inode
;
209 struct fuse_conn
*fc
= get_fuse_conn(inode
);
210 struct fuse_file
*ff
= file
->private_data
;
211 struct fuse_req
*req
;
212 struct fuse_fsync_in inarg
;
215 if (is_bad_inode(inode
))
218 if ((!isdir
&& fc
->no_fsync
) || (isdir
&& fc
->no_fsyncdir
))
221 req
= fuse_get_request(fc
);
225 memset(&inarg
, 0, sizeof(inarg
));
227 inarg
.fsync_flags
= datasync
? 1 : 0;
228 req
->in
.h
.opcode
= isdir
? FUSE_FSYNCDIR
: FUSE_FSYNC
;
229 req
->in
.h
.nodeid
= get_node_id(inode
);
233 req
->in
.args
[0].size
= sizeof(inarg
);
234 req
->in
.args
[0].value
= &inarg
;
235 request_send(fc
, req
);
236 err
= req
->out
.h
.error
;
237 fuse_put_request(fc
, req
);
238 if (err
== -ENOSYS
) {
248 static int fuse_fsync(struct file
*file
, struct dentry
*de
, int datasync
)
250 return fuse_fsync_common(file
, de
, datasync
, 0);
253 void fuse_read_fill(struct fuse_req
*req
, struct file
*file
,
254 struct inode
*inode
, loff_t pos
, size_t count
, int opcode
)
256 struct fuse_file
*ff
= file
->private_data
;
257 struct fuse_read_in
*inarg
= &req
->misc
.read_in
;
262 req
->in
.h
.opcode
= opcode
;
263 req
->in
.h
.nodeid
= get_node_id(inode
);
267 req
->in
.args
[0].size
= sizeof(struct fuse_read_in
);
268 req
->in
.args
[0].value
= &inarg
;
269 req
->out
.argpages
= 1;
271 req
->out
.numargs
= 1;
272 req
->out
.args
[0].size
= count
;
275 static size_t fuse_send_read(struct fuse_req
*req
, struct file
*file
,
276 struct inode
*inode
, loff_t pos
, size_t count
)
278 struct fuse_conn
*fc
= get_fuse_conn(inode
);
279 fuse_read_fill(req
, file
, inode
, pos
, count
, FUSE_READ
);
280 request_send(fc
, req
);
281 return req
->out
.args
[0].size
;
284 static int fuse_readpage(struct file
*file
, struct page
*page
)
286 struct inode
*inode
= page
->mapping
->host
;
287 struct fuse_conn
*fc
= get_fuse_conn(inode
);
288 struct fuse_req
*req
;
292 if (is_bad_inode(inode
))
296 req
= fuse_get_request(fc
);
300 req
->out
.page_zeroing
= 1;
302 req
->pages
[0] = page
;
303 fuse_send_read(req
, file
, inode
, page_offset(page
), PAGE_CACHE_SIZE
);
304 err
= req
->out
.h
.error
;
305 fuse_put_request(fc
, req
);
307 SetPageUptodate(page
);
308 fuse_invalidate_attr(inode
); /* atime changed */
314 static int fuse_send_readpages(struct fuse_req
*req
, struct file
*file
,
317 loff_t pos
= page_offset(req
->pages
[0]);
318 size_t count
= req
->num_pages
<< PAGE_CACHE_SHIFT
;
320 req
->out
.page_zeroing
= 1;
321 fuse_send_read(req
, file
, inode
, pos
, count
);
322 for (i
= 0; i
< req
->num_pages
; i
++) {
323 struct page
*page
= req
->pages
[i
];
324 if (!req
->out
.h
.error
)
325 SetPageUptodate(page
);
328 return req
->out
.h
.error
;
331 struct fuse_readpages_data
{
332 struct fuse_req
*req
;
337 static int fuse_readpages_fill(void *_data
, struct page
*page
)
339 struct fuse_readpages_data
*data
= _data
;
340 struct fuse_req
*req
= data
->req
;
341 struct inode
*inode
= data
->inode
;
342 struct fuse_conn
*fc
= get_fuse_conn(inode
);
344 if (req
->num_pages
&&
345 (req
->num_pages
== FUSE_MAX_PAGES_PER_REQ
||
346 (req
->num_pages
+ 1) * PAGE_CACHE_SIZE
> fc
->max_read
||
347 req
->pages
[req
->num_pages
- 1]->index
+ 1 != page
->index
)) {
348 int err
= fuse_send_readpages(req
, data
->file
, inode
);
353 fuse_reset_request(req
);
355 req
->pages
[req
->num_pages
] = page
;
360 static int fuse_readpages(struct file
*file
, struct address_space
*mapping
,
361 struct list_head
*pages
, unsigned nr_pages
)
363 struct inode
*inode
= mapping
->host
;
364 struct fuse_conn
*fc
= get_fuse_conn(inode
);
365 struct fuse_readpages_data data
;
368 if (is_bad_inode(inode
))
373 data
.req
= fuse_get_request(fc
);
377 err
= read_cache_pages(mapping
, pages
, fuse_readpages_fill
, &data
);
378 if (!err
&& data
.req
->num_pages
)
379 err
= fuse_send_readpages(data
.req
, file
, inode
);
380 fuse_put_request(fc
, data
.req
);
381 fuse_invalidate_attr(inode
); /* atime changed */
385 static size_t fuse_send_write(struct fuse_req
*req
, struct file
*file
,
386 struct inode
*inode
, loff_t pos
, size_t count
)
388 struct fuse_conn
*fc
= get_fuse_conn(inode
);
389 struct fuse_file
*ff
= file
->private_data
;
390 struct fuse_write_in inarg
;
391 struct fuse_write_out outarg
;
393 memset(&inarg
, 0, sizeof(struct fuse_write_in
));
397 req
->in
.h
.opcode
= FUSE_WRITE
;
398 req
->in
.h
.nodeid
= get_node_id(inode
);
401 req
->in
.argpages
= 1;
403 req
->in
.args
[0].size
= sizeof(struct fuse_write_in
);
404 req
->in
.args
[0].value
= &inarg
;
405 req
->in
.args
[1].size
= count
;
406 req
->out
.numargs
= 1;
407 req
->out
.args
[0].size
= sizeof(struct fuse_write_out
);
408 req
->out
.args
[0].value
= &outarg
;
409 request_send(fc
, req
);
413 static int fuse_prepare_write(struct file
*file
, struct page
*page
,
414 unsigned offset
, unsigned to
)
420 static int fuse_commit_write(struct file
*file
, struct page
*page
,
421 unsigned offset
, unsigned to
)
425 unsigned count
= to
- offset
;
426 struct inode
*inode
= page
->mapping
->host
;
427 struct fuse_conn
*fc
= get_fuse_conn(inode
);
428 loff_t pos
= page_offset(page
) + offset
;
429 struct fuse_req
*req
;
431 if (is_bad_inode(inode
))
434 req
= fuse_get_request(fc
);
439 req
->pages
[0] = page
;
440 req
->page_offset
= offset
;
441 nres
= fuse_send_write(req
, file
, inode
, pos
, count
);
442 err
= req
->out
.h
.error
;
443 fuse_put_request(fc
, req
);
444 if (!err
&& nres
!= count
)
448 if (pos
> i_size_read(inode
))
449 i_size_write(inode
, pos
);
451 if (offset
== 0 && to
== PAGE_CACHE_SIZE
) {
452 clear_page_dirty(page
);
453 SetPageUptodate(page
);
456 fuse_invalidate_attr(inode
);
460 static void fuse_release_user_pages(struct fuse_req
*req
, int write
)
464 for (i
= 0; i
< req
->num_pages
; i
++) {
465 struct page
*page
= req
->pages
[i
];
467 set_page_dirty_lock(page
);
472 static int fuse_get_user_pages(struct fuse_req
*req
, const char __user
*buf
,
473 unsigned nbytes
, int write
)
475 unsigned long user_addr
= (unsigned long) buf
;
476 unsigned offset
= user_addr
& ~PAGE_MASK
;
479 /* This doesn't work with nfsd */
483 nbytes
= min(nbytes
, (unsigned) FUSE_MAX_PAGES_PER_REQ
<< PAGE_SHIFT
);
484 npages
= (nbytes
+ offset
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
485 npages
= min(max(npages
, 1), FUSE_MAX_PAGES_PER_REQ
);
486 down_read(¤t
->mm
->mmap_sem
);
487 npages
= get_user_pages(current
, current
->mm
, user_addr
, npages
, write
,
488 0, req
->pages
, NULL
);
489 up_read(¤t
->mm
->mmap_sem
);
493 req
->num_pages
= npages
;
494 req
->page_offset
= offset
;
498 static ssize_t
fuse_direct_io(struct file
*file
, const char __user
*buf
,
499 size_t count
, loff_t
*ppos
, int write
)
501 struct inode
*inode
= file
->f_dentry
->d_inode
;
502 struct fuse_conn
*fc
= get_fuse_conn(inode
);
503 size_t nmax
= write
? fc
->max_write
: fc
->max_read
;
506 struct fuse_req
*req
;
508 if (is_bad_inode(inode
))
511 req
= fuse_get_request(fc
);
517 size_t nbytes
= min(count
, nmax
);
518 int err
= fuse_get_user_pages(req
, buf
, nbytes
, !write
);
523 nbytes
= (req
->num_pages
<< PAGE_SHIFT
) - req
->page_offset
;
524 nbytes
= min(count
, nbytes
);
526 nres
= fuse_send_write(req
, file
, inode
, pos
, nbytes
);
528 nres
= fuse_send_read(req
, file
, inode
, pos
, nbytes
);
529 fuse_release_user_pages(req
, !write
);
530 if (req
->out
.h
.error
) {
532 res
= req
->out
.h
.error
;
534 } else if (nres
> nbytes
) {
545 fuse_reset_request(req
);
547 fuse_put_request(fc
, req
);
549 if (write
&& pos
> i_size_read(inode
))
550 i_size_write(inode
, pos
);
553 fuse_invalidate_attr(inode
);
558 static ssize_t
fuse_direct_read(struct file
*file
, char __user
*buf
,
559 size_t count
, loff_t
*ppos
)
561 return fuse_direct_io(file
, buf
, count
, ppos
, 0);
564 static ssize_t
fuse_direct_write(struct file
*file
, const char __user
*buf
,
565 size_t count
, loff_t
*ppos
)
567 struct inode
*inode
= file
->f_dentry
->d_inode
;
569 /* Don't allow parallel writes to the same file */
570 mutex_lock(&inode
->i_mutex
);
571 res
= fuse_direct_io(file
, buf
, count
, ppos
, 1);
572 mutex_unlock(&inode
->i_mutex
);
576 static int fuse_file_mmap(struct file
*file
, struct vm_area_struct
*vma
)
578 if ((vma
->vm_flags
& VM_SHARED
)) {
579 if ((vma
->vm_flags
& VM_WRITE
))
582 vma
->vm_flags
&= ~VM_MAYWRITE
;
584 return generic_file_mmap(file
, vma
);
587 static int fuse_set_page_dirty(struct page
*page
)
589 printk("fuse_set_page_dirty: should not happen\n");
594 static struct file_operations fuse_file_operations
= {
595 .llseek
= generic_file_llseek
,
596 .read
= generic_file_read
,
597 .write
= generic_file_write
,
598 .mmap
= fuse_file_mmap
,
601 .release
= fuse_release
,
603 .sendfile
= generic_file_sendfile
,
606 static struct file_operations fuse_direct_io_file_operations
= {
607 .llseek
= generic_file_llseek
,
608 .read
= fuse_direct_read
,
609 .write
= fuse_direct_write
,
612 .release
= fuse_release
,
614 /* no mmap and sendfile */
617 static struct address_space_operations fuse_file_aops
= {
618 .readpage
= fuse_readpage
,
619 .prepare_write
= fuse_prepare_write
,
620 .commit_write
= fuse_commit_write
,
621 .readpages
= fuse_readpages
,
622 .set_page_dirty
= fuse_set_page_dirty
,
625 void fuse_init_file_inode(struct inode
*inode
)
627 inode
->i_fop
= &fuse_file_operations
;
628 inode
->i_data
.a_ops
= &fuse_file_aops
;