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
;
169 req
= fuse_get_request(fc
);
173 memset(&inarg
, 0, sizeof(inarg
));
175 req
->in
.h
.opcode
= FUSE_FLUSH
;
176 req
->in
.h
.nodeid
= get_node_id(inode
);
180 req
->in
.args
[0].size
= sizeof(inarg
);
181 req
->in
.args
[0].value
= &inarg
;
182 request_send(fc
, req
);
183 err
= req
->out
.h
.error
;
184 fuse_put_request(fc
, req
);
185 if (err
== -ENOSYS
) {
192 int fuse_fsync_common(struct file
*file
, struct dentry
*de
, int datasync
,
195 struct inode
*inode
= de
->d_inode
;
196 struct fuse_conn
*fc
= get_fuse_conn(inode
);
197 struct fuse_file
*ff
= file
->private_data
;
198 struct fuse_req
*req
;
199 struct fuse_fsync_in inarg
;
202 if ((!isdir
&& fc
->no_fsync
) || (isdir
&& fc
->no_fsyncdir
))
205 req
= fuse_get_request(fc
);
209 memset(&inarg
, 0, sizeof(inarg
));
211 inarg
.fsync_flags
= datasync
? 1 : 0;
212 req
->in
.h
.opcode
= isdir
? FUSE_FSYNCDIR
: FUSE_FSYNC
;
213 req
->in
.h
.nodeid
= get_node_id(inode
);
217 req
->in
.args
[0].size
= sizeof(inarg
);
218 req
->in
.args
[0].value
= &inarg
;
219 request_send(fc
, req
);
220 err
= req
->out
.h
.error
;
221 fuse_put_request(fc
, req
);
222 if (err
== -ENOSYS
) {
232 static int fuse_fsync(struct file
*file
, struct dentry
*de
, int datasync
)
234 return fuse_fsync_common(file
, de
, datasync
, 0);
237 size_t fuse_send_read_common(struct fuse_req
*req
, struct file
*file
,
238 struct inode
*inode
, loff_t pos
, size_t count
,
241 struct fuse_conn
*fc
= get_fuse_conn(inode
);
242 struct fuse_file
*ff
= file
->private_data
;
243 struct fuse_read_in inarg
;
245 memset(&inarg
, 0, sizeof(struct fuse_read_in
));
249 req
->in
.h
.opcode
= isdir
? FUSE_READDIR
: FUSE_READ
;
250 req
->in
.h
.nodeid
= get_node_id(inode
);
254 req
->in
.args
[0].size
= sizeof(struct fuse_read_in
);
255 req
->in
.args
[0].value
= &inarg
;
256 req
->out
.argpages
= 1;
258 req
->out
.numargs
= 1;
259 req
->out
.args
[0].size
= count
;
260 request_send(fc
, req
);
261 return req
->out
.args
[0].size
;
264 static inline size_t fuse_send_read(struct fuse_req
*req
, struct file
*file
,
265 struct inode
*inode
, loff_t pos
,
268 return fuse_send_read_common(req
, file
, inode
, pos
, count
, 0);
271 static int fuse_readpage(struct file
*file
, struct page
*page
)
273 struct inode
*inode
= page
->mapping
->host
;
274 struct fuse_conn
*fc
= get_fuse_conn(inode
);
275 loff_t pos
= (loff_t
) page
->index
<< PAGE_CACHE_SHIFT
;
276 struct fuse_req
*req
= fuse_get_request(fc
);
281 req
->out
.page_zeroing
= 1;
283 req
->pages
[0] = page
;
284 fuse_send_read(req
, file
, inode
, pos
, PAGE_CACHE_SIZE
);
285 err
= req
->out
.h
.error
;
286 fuse_put_request(fc
, req
);
288 SetPageUptodate(page
);
289 fuse_invalidate_attr(inode
); /* atime changed */
295 static int fuse_send_readpages(struct fuse_req
*req
, struct file
*file
,
298 loff_t pos
= (loff_t
) req
->pages
[0]->index
<< PAGE_CACHE_SHIFT
;
299 size_t count
= req
->num_pages
<< PAGE_CACHE_SHIFT
;
301 req
->out
.page_zeroing
= 1;
302 fuse_send_read(req
, file
, inode
, pos
, count
);
303 for (i
= 0; i
< req
->num_pages
; i
++) {
304 struct page
*page
= req
->pages
[i
];
305 if (!req
->out
.h
.error
)
306 SetPageUptodate(page
);
309 return req
->out
.h
.error
;
312 struct fuse_readpages_data
{
313 struct fuse_req
*req
;
318 static int fuse_readpages_fill(void *_data
, struct page
*page
)
320 struct fuse_readpages_data
*data
= _data
;
321 struct fuse_req
*req
= data
->req
;
322 struct inode
*inode
= data
->inode
;
323 struct fuse_conn
*fc
= get_fuse_conn(inode
);
325 if (req
->num_pages
&&
326 (req
->num_pages
== FUSE_MAX_PAGES_PER_REQ
||
327 (req
->num_pages
+ 1) * PAGE_CACHE_SIZE
> fc
->max_read
||
328 req
->pages
[req
->num_pages
- 1]->index
+ 1 != page
->index
)) {
329 int err
= fuse_send_readpages(req
, data
->file
, inode
);
334 fuse_reset_request(req
);
336 req
->pages
[req
->num_pages
] = page
;
341 static int fuse_readpages(struct file
*file
, struct address_space
*mapping
,
342 struct list_head
*pages
, unsigned nr_pages
)
344 struct inode
*inode
= mapping
->host
;
345 struct fuse_conn
*fc
= get_fuse_conn(inode
);
346 struct fuse_readpages_data data
;
350 data
.req
= fuse_get_request(fc
);
354 err
= read_cache_pages(mapping
, pages
, fuse_readpages_fill
, &data
);
355 if (!err
&& data
.req
->num_pages
)
356 err
= fuse_send_readpages(data
.req
, file
, inode
);
357 fuse_put_request(fc
, data
.req
);
358 fuse_invalidate_attr(inode
); /* atime changed */
362 static size_t fuse_send_write(struct fuse_req
*req
, struct file
*file
,
363 struct inode
*inode
, loff_t pos
, size_t count
)
365 struct fuse_conn
*fc
= get_fuse_conn(inode
);
366 struct fuse_file
*ff
= file
->private_data
;
367 struct fuse_write_in inarg
;
368 struct fuse_write_out outarg
;
370 memset(&inarg
, 0, sizeof(struct fuse_write_in
));
374 req
->in
.h
.opcode
= FUSE_WRITE
;
375 req
->in
.h
.nodeid
= get_node_id(inode
);
378 req
->in
.argpages
= 1;
380 req
->in
.args
[0].size
= sizeof(struct fuse_write_in
);
381 req
->in
.args
[0].value
= &inarg
;
382 req
->in
.args
[1].size
= count
;
383 req
->out
.numargs
= 1;
384 req
->out
.args
[0].size
= sizeof(struct fuse_write_out
);
385 req
->out
.args
[0].value
= &outarg
;
386 request_send(fc
, req
);
390 static int fuse_prepare_write(struct file
*file
, struct page
*page
,
391 unsigned offset
, unsigned to
)
397 static int fuse_commit_write(struct file
*file
, struct page
*page
,
398 unsigned offset
, unsigned to
)
402 unsigned count
= to
- offset
;
403 struct inode
*inode
= page
->mapping
->host
;
404 struct fuse_conn
*fc
= get_fuse_conn(inode
);
405 loff_t pos
= ((loff_t
) page
->index
<< PAGE_CACHE_SHIFT
) + offset
;
406 struct fuse_req
*req
= fuse_get_request(fc
);
411 req
->pages
[0] = page
;
412 req
->page_offset
= offset
;
413 nres
= fuse_send_write(req
, file
, inode
, pos
, count
);
414 err
= req
->out
.h
.error
;
415 fuse_put_request(fc
, req
);
416 if (!err
&& nres
!= count
)
420 if (pos
> i_size_read(inode
))
421 i_size_write(inode
, pos
);
423 if (offset
== 0 && to
== PAGE_CACHE_SIZE
) {
424 clear_page_dirty(page
);
425 SetPageUptodate(page
);
428 fuse_invalidate_attr(inode
);
432 static void fuse_release_user_pages(struct fuse_req
*req
, int write
)
436 for (i
= 0; i
< req
->num_pages
; i
++) {
437 struct page
*page
= req
->pages
[i
];
439 set_page_dirty_lock(page
);
444 static int fuse_get_user_pages(struct fuse_req
*req
, const char __user
*buf
,
445 unsigned nbytes
, int write
)
447 unsigned long user_addr
= (unsigned long) buf
;
448 unsigned offset
= user_addr
& ~PAGE_MASK
;
451 /* This doesn't work with nfsd */
455 nbytes
= min(nbytes
, (unsigned) FUSE_MAX_PAGES_PER_REQ
<< PAGE_SHIFT
);
456 npages
= (nbytes
+ offset
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
457 npages
= min(npages
, FUSE_MAX_PAGES_PER_REQ
);
458 down_read(¤t
->mm
->mmap_sem
);
459 npages
= get_user_pages(current
, current
->mm
, user_addr
, npages
, write
,
460 0, req
->pages
, NULL
);
461 up_read(¤t
->mm
->mmap_sem
);
465 req
->num_pages
= npages
;
466 req
->page_offset
= offset
;
470 static ssize_t
fuse_direct_io(struct file
*file
, const char __user
*buf
,
471 size_t count
, loff_t
*ppos
, int write
)
473 struct inode
*inode
= file
->f_dentry
->d_inode
;
474 struct fuse_conn
*fc
= get_fuse_conn(inode
);
475 size_t nmax
= write
? fc
->max_write
: fc
->max_read
;
478 struct fuse_req
*req
= fuse_get_request(fc
);
485 size_t nbytes
= min(count
, nmax
);
486 int err
= fuse_get_user_pages(req
, buf
, nbytes
, !write
);
491 tmp
= (req
->num_pages
<< PAGE_SHIFT
) - req
->page_offset
;
492 nbytes
= min(nbytes
, tmp
);
494 nres
= fuse_send_write(req
, file
, inode
, pos
, nbytes
);
496 nres
= fuse_send_read(req
, file
, inode
, pos
, nbytes
);
497 fuse_release_user_pages(req
, !write
);
498 if (req
->out
.h
.error
) {
500 res
= req
->out
.h
.error
;
502 } else if (nres
> nbytes
) {
513 fuse_reset_request(req
);
515 fuse_put_request(fc
, req
);
517 if (write
&& pos
> i_size_read(inode
))
518 i_size_write(inode
, pos
);
521 fuse_invalidate_attr(inode
);
526 static ssize_t
fuse_direct_read(struct file
*file
, char __user
*buf
,
527 size_t count
, loff_t
*ppos
)
529 return fuse_direct_io(file
, buf
, count
, ppos
, 0);
532 static ssize_t
fuse_direct_write(struct file
*file
, const char __user
*buf
,
533 size_t count
, loff_t
*ppos
)
535 struct inode
*inode
= file
->f_dentry
->d_inode
;
537 /* Don't allow parallel writes to the same file */
539 res
= fuse_direct_io(file
, buf
, count
, ppos
, 1);
544 static int fuse_file_mmap(struct file
*file
, struct vm_area_struct
*vma
)
546 if ((vma
->vm_flags
& VM_SHARED
)) {
547 if ((vma
->vm_flags
& VM_WRITE
))
550 vma
->vm_flags
&= ~VM_MAYWRITE
;
552 return generic_file_mmap(file
, vma
);
555 static int fuse_set_page_dirty(struct page
*page
)
557 printk("fuse_set_page_dirty: should not happen\n");
562 static struct file_operations fuse_file_operations
= {
563 .llseek
= generic_file_llseek
,
564 .read
= generic_file_read
,
565 .write
= generic_file_write
,
566 .mmap
= fuse_file_mmap
,
569 .release
= fuse_release
,
571 .sendfile
= generic_file_sendfile
,
574 static struct file_operations fuse_direct_io_file_operations
= {
575 .llseek
= generic_file_llseek
,
576 .read
= fuse_direct_read
,
577 .write
= fuse_direct_write
,
580 .release
= fuse_release
,
582 /* no mmap and sendfile */
585 static struct address_space_operations fuse_file_aops
= {
586 .readpage
= fuse_readpage
,
587 .prepare_write
= fuse_prepare_write
,
588 .commit_write
= fuse_commit_write
,
589 .readpages
= fuse_readpages
,
590 .set_page_dirty
= fuse_set_page_dirty
,
593 void fuse_init_file_inode(struct inode
*inode
)
595 inode
->i_fop
= &fuse_file_operations
;
596 inode
->i_data
.a_ops
= &fuse_file_aops
;