2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2008 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>
14 #include <linux/sched.h>
15 #include <linux/module.h>
16 #include <linux/compat.h>
17 #include <linux/swap.h>
18 #include <linux/aio.h>
19 #include <linux/falloc.h>
21 static const struct file_operations fuse_direct_io_file_operations;
23 static int fuse_send_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
24 int opcode, struct fuse_open_out *outargp)
26 struct fuse_open_in inarg;
30 req = fuse_get_req_nopages(fc);
34 memset(&inarg, 0, sizeof(inarg));
35 inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY);
36 if (!fc->atomic_o_trunc)
37 inarg.flags &= ~O_TRUNC;
38 req->in.h.opcode = opcode;
39 req->in.h.nodeid = nodeid;
41 req->in.args[0].size = sizeof(inarg);
42 req->in.args[0].value = &inarg;
44 req->out.args[0].size = sizeof(*outargp);
45 req->out.args[0].value = outargp;
46 fuse_request_send(fc, req);
47 err = req->out.h.error;
48 fuse_put_request(fc, req);
53 struct fuse_file *fuse_file_alloc(struct fuse_conn *fc)
57 ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
62 ff->reserved_req = fuse_request_alloc(0);
63 if (unlikely(!ff->reserved_req)) {
68 INIT_LIST_HEAD(&ff->write_entry);
69 atomic_set(&ff->count, 0);
70 RB_CLEAR_NODE(&ff->polled_node);
71 init_waitqueue_head(&ff->poll_wait);
75 spin_unlock(&fc->lock);
80 void fuse_file_free(struct fuse_file *ff)
82 fuse_request_free(ff->reserved_req);
86 struct fuse_file *fuse_file_get(struct fuse_file *ff)
88 atomic_inc(&ff->count);
92 static void fuse_release_async(struct work_struct *work)
98 req = container_of(work, struct fuse_req, misc.release.work);
99 path = req->misc.release.path;
100 fc = get_fuse_conn(path.dentry->d_inode);
102 fuse_put_request(fc, req);
106 static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
108 if (fc->destroy_req) {
110 * If this is a fuseblk mount, then it's possible that
111 * releasing the path will result in releasing the
112 * super block and sending the DESTROY request. If
113 * the server is single threaded, this would hang.
114 * For this reason do the path_put() in a separate
117 atomic_inc(&req->count);
118 INIT_WORK(&req->misc.release.work, fuse_release_async);
119 schedule_work(&req->misc.release.work);
121 path_put(&req->misc.release.path);
125 static void fuse_file_put(struct fuse_file *ff, bool sync)
127 if (atomic_dec_and_test(&ff->count)) {
128 struct fuse_req *req = ff->reserved_req;
132 fuse_request_send(ff->fc, req);
133 path_put(&req->misc.release.path);
134 fuse_put_request(ff->fc, req);
136 req->end = fuse_release_end;
138 fuse_request_send_background(ff->fc, req);
144 int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
147 struct fuse_open_out outarg;
148 struct fuse_file *ff;
150 int opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
152 ff = fuse_file_alloc(fc);
156 err = fuse_send_open(fc, nodeid, file, opcode, &outarg);
163 outarg.open_flags &= ~FOPEN_DIRECT_IO;
167 ff->open_flags = outarg.open_flags;
168 file->private_data = fuse_file_get(ff);
172 EXPORT_SYMBOL_GPL(fuse_do_open);
174 void fuse_finish_open(struct inode *inode, struct file *file)
176 struct fuse_file *ff = file->private_data;
177 struct fuse_conn *fc = get_fuse_conn(inode);
179 if (ff->open_flags & FOPEN_DIRECT_IO)
180 file->f_op = &fuse_direct_io_file_operations;
181 if (!(ff->open_flags & FOPEN_KEEP_CACHE))
182 invalidate_inode_pages2(inode->i_mapping);
183 if (ff->open_flags & FOPEN_NONSEEKABLE)
184 nonseekable_open(inode, file);
185 if (fc->atomic_o_trunc && (file->f_flags & O_TRUNC)) {
186 struct fuse_inode *fi = get_fuse_inode(inode);
188 spin_lock(&fc->lock);
189 fi->attr_version = ++fc->attr_version;
190 i_size_write(inode, 0);
191 spin_unlock(&fc->lock);
192 fuse_invalidate_attr(inode);
196 int fuse_open_common(struct inode *inode, struct file *file, bool isdir)
198 struct fuse_conn *fc = get_fuse_conn(inode);
201 err = generic_file_open(inode, file);
205 err = fuse_do_open(fc, get_node_id(inode), file, isdir);
209 fuse_finish_open(inode, file);
214 static void fuse_prepare_release(struct fuse_file *ff, int flags, int opcode)
216 struct fuse_conn *fc = ff->fc;
217 struct fuse_req *req = ff->reserved_req;
218 struct fuse_release_in *inarg = &req->misc.release.in;
220 spin_lock(&fc->lock);
221 list_del(&ff->write_entry);
222 if (!RB_EMPTY_NODE(&ff->polled_node))
223 rb_erase(&ff->polled_node, &fc->polled_files);
224 spin_unlock(&fc->lock);
226 wake_up_interruptible_all(&ff->poll_wait);
229 inarg->flags = flags;
230 req->in.h.opcode = opcode;
231 req->in.h.nodeid = ff->nodeid;
233 req->in.args[0].size = sizeof(struct fuse_release_in);
234 req->in.args[0].value = inarg;
237 void fuse_release_common(struct file *file, int opcode)
239 struct fuse_file *ff;
240 struct fuse_req *req;
242 ff = file->private_data;
246 req = ff->reserved_req;
247 fuse_prepare_release(ff, file->f_flags, opcode);
250 struct fuse_release_in *inarg = &req->misc.release.in;
251 inarg->release_flags |= FUSE_RELEASE_FLOCK_UNLOCK;
252 inarg->lock_owner = fuse_lock_owner_id(ff->fc,
255 /* Hold vfsmount and dentry until release is finished */
256 path_get(&file->f_path);
257 req->misc.release.path = file->f_path;
260 * Normally this will send the RELEASE request, however if
261 * some asynchronous READ or WRITE requests are outstanding,
262 * the sending will be delayed.
264 * Make the release synchronous if this is a fuseblk mount,
265 * synchronous RELEASE is allowed (and desirable) in this case
266 * because the server can be trusted not to screw up.
268 fuse_file_put(ff, ff->fc->destroy_req != NULL);
271 static int fuse_open(struct inode *inode, struct file *file)
273 return fuse_open_common(inode, file, false);
276 static int fuse_release(struct inode *inode, struct file *file)
278 fuse_release_common(file, FUSE_RELEASE);
280 /* return value is ignored by VFS */
284 void fuse_sync_release(struct fuse_file *ff, int flags)
286 WARN_ON(atomic_read(&ff->count) > 1);
287 fuse_prepare_release(ff, flags, FUSE_RELEASE);
288 ff->reserved_req->force = 1;
289 ff->reserved_req->background = 0;
290 fuse_request_send(ff->fc, ff->reserved_req);
291 fuse_put_request(ff->fc, ff->reserved_req);
294 EXPORT_SYMBOL_GPL(fuse_sync_release);
297 * Scramble the ID space with XTEA, so that the value of the files_struct
298 * pointer is not exposed to userspace.
300 u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
302 u32 *k = fc->scramble_key;
303 u64 v = (unsigned long) id;
309 for (i = 0; i < 32; i++) {
310 v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
312 v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
315 return (u64) v0 + ((u64) v1 << 32);
319 * Check if page is under writeback
321 * This is currently done by walking the list of writepage requests
322 * for the inode, which can be pretty inefficient.
324 static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index)
326 struct fuse_conn *fc = get_fuse_conn(inode);
327 struct fuse_inode *fi = get_fuse_inode(inode);
328 struct fuse_req *req;
331 spin_lock(&fc->lock);
332 list_for_each_entry(req, &fi->writepages, writepages_entry) {
335 BUG_ON(req->inode != inode);
336 curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
337 if (curr_index <= index &&
338 index < curr_index + req->num_pages) {
343 spin_unlock(&fc->lock);
349 * Wait for page writeback to be completed.
351 * Since fuse doesn't rely on the VM writeback tracking, this has to
352 * use some other means.
354 static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index)
356 struct fuse_inode *fi = get_fuse_inode(inode);
358 wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index));
362 static int fuse_flush(struct file *file, fl_owner_t id)
364 struct inode *inode = file_inode(file);
365 struct fuse_conn *fc = get_fuse_conn(inode);
366 struct fuse_file *ff = file->private_data;
367 struct fuse_req *req;
368 struct fuse_flush_in inarg;
371 if (is_bad_inode(inode))
377 req = fuse_get_req_nofail_nopages(fc, file);
378 memset(&inarg, 0, sizeof(inarg));
380 inarg.lock_owner = fuse_lock_owner_id(fc, id);
381 req->in.h.opcode = FUSE_FLUSH;
382 req->in.h.nodeid = get_node_id(inode);
384 req->in.args[0].size = sizeof(inarg);
385 req->in.args[0].value = &inarg;
387 fuse_request_send(fc, req);
388 err = req->out.h.error;
389 fuse_put_request(fc, req);
390 if (err == -ENOSYS) {
398 * Wait for all pending writepages on the inode to finish.
400 * This is currently done by blocking further writes with FUSE_NOWRITE
401 * and waiting for all sent writes to complete.
403 * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage
404 * could conflict with truncation.
406 static void fuse_sync_writes(struct inode *inode)
408 fuse_set_nowrite(inode);
409 fuse_release_nowrite(inode);
412 int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
413 int datasync, int isdir)
415 struct inode *inode = file->f_mapping->host;
416 struct fuse_conn *fc = get_fuse_conn(inode);
417 struct fuse_file *ff = file->private_data;
418 struct fuse_req *req;
419 struct fuse_fsync_in inarg;
422 if (is_bad_inode(inode))
425 err = filemap_write_and_wait_range(inode->i_mapping, start, end);
429 if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
432 mutex_lock(&inode->i_mutex);
435 * Start writeback against all dirty pages of the inode, then
436 * wait for all outstanding writes, before sending the FSYNC
439 err = write_inode_now(inode, 0);
443 fuse_sync_writes(inode);
445 req = fuse_get_req_nopages(fc);
451 memset(&inarg, 0, sizeof(inarg));
453 inarg.fsync_flags = datasync ? 1 : 0;
454 req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
455 req->in.h.nodeid = get_node_id(inode);
457 req->in.args[0].size = sizeof(inarg);
458 req->in.args[0].value = &inarg;
459 fuse_request_send(fc, req);
460 err = req->out.h.error;
461 fuse_put_request(fc, req);
462 if (err == -ENOSYS) {
470 mutex_unlock(&inode->i_mutex);
474 static int fuse_fsync(struct file *file, loff_t start, loff_t end,
477 return fuse_fsync_common(file, start, end, datasync, 0);
480 void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos,
481 size_t count, int opcode)
483 struct fuse_read_in *inarg = &req->misc.read.in;
484 struct fuse_file *ff = file->private_data;
489 inarg->flags = file->f_flags;
490 req->in.h.opcode = opcode;
491 req->in.h.nodeid = ff->nodeid;
493 req->in.args[0].size = sizeof(struct fuse_read_in);
494 req->in.args[0].value = inarg;
496 req->out.numargs = 1;
497 req->out.args[0].size = count;
500 static void fuse_release_user_pages(struct fuse_req *req, int write)
504 for (i = 0; i < req->num_pages; i++) {
505 struct page *page = req->pages[i];
507 set_page_dirty_lock(page);
513 * In case of short read, the caller sets 'pos' to the position of
514 * actual end of fuse request in IO request. Otherwise, if bytes_requested
515 * == bytes_transferred or rw == WRITE, the caller sets 'pos' to -1.
518 * User requested DIO read of 64K. It was splitted into two 32K fuse requests,
519 * both submitted asynchronously. The first of them was ACKed by userspace as
520 * fully completed (req->out.args[0].size == 32K) resulting in pos == -1. The
521 * second request was ACKed as short, e.g. only 1K was read, resulting in
524 * Thus, when all fuse requests are completed, the minimal non-negative 'pos'
525 * will be equal to the length of the longest contiguous fragment of
526 * transferred data starting from the beginning of IO request.
528 static void fuse_aio_complete(struct fuse_io_priv *io, int err, ssize_t pos)
532 spin_lock(&io->lock);
534 io->err = io->err ? : err;
535 else if (pos >= 0 && (io->bytes < 0 || pos < io->bytes))
539 spin_unlock(&io->lock);
546 else if (io->bytes >= 0 && io->write)
549 res = io->bytes < 0 ? io->size : io->bytes;
551 if (!is_sync_kiocb(io->iocb)) {
552 struct inode *inode = file_inode(io->iocb->ki_filp);
553 struct fuse_conn *fc = get_fuse_conn(inode);
554 struct fuse_inode *fi = get_fuse_inode(inode);
556 spin_lock(&fc->lock);
557 fi->attr_version = ++fc->attr_version;
558 spin_unlock(&fc->lock);
562 aio_complete(io->iocb, res, 0);
567 static void fuse_aio_complete_req(struct fuse_conn *fc, struct fuse_req *req)
569 struct fuse_io_priv *io = req->io;
572 fuse_release_user_pages(req, !io->write);
575 if (req->misc.write.in.size != req->misc.write.out.size)
576 pos = req->misc.write.in.offset - io->offset +
577 req->misc.write.out.size;
579 if (req->misc.read.in.size != req->out.args[0].size)
580 pos = req->misc.read.in.offset - io->offset +
581 req->out.args[0].size;
584 fuse_aio_complete(io, req->out.h.error, pos);
587 static size_t fuse_async_req_send(struct fuse_conn *fc, struct fuse_req *req,
588 size_t num_bytes, struct fuse_io_priv *io)
590 spin_lock(&io->lock);
591 io->size += num_bytes;
593 spin_unlock(&io->lock);
596 req->end = fuse_aio_complete_req;
598 __fuse_get_request(req);
599 fuse_request_send_background(fc, req);
604 static size_t fuse_send_read(struct fuse_req *req, struct fuse_io_priv *io,
605 loff_t pos, size_t count, fl_owner_t owner)
607 struct file *file = io->file;
608 struct fuse_file *ff = file->private_data;
609 struct fuse_conn *fc = ff->fc;
611 fuse_read_fill(req, file, pos, count, FUSE_READ);
613 struct fuse_read_in *inarg = &req->misc.read.in;
615 inarg->read_flags |= FUSE_READ_LOCKOWNER;
616 inarg->lock_owner = fuse_lock_owner_id(fc, owner);
620 return fuse_async_req_send(fc, req, count, io);
622 fuse_request_send(fc, req);
623 return req->out.args[0].size;
626 static void fuse_read_update_size(struct inode *inode, loff_t size,
629 struct fuse_conn *fc = get_fuse_conn(inode);
630 struct fuse_inode *fi = get_fuse_inode(inode);
632 spin_lock(&fc->lock);
633 if (attr_ver == fi->attr_version && size < inode->i_size &&
634 !test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
635 fi->attr_version = ++fc->attr_version;
636 i_size_write(inode, size);
638 spin_unlock(&fc->lock);
641 static int fuse_readpage(struct file *file, struct page *page)
643 struct fuse_io_priv io = { .async = 0, .file = file };
644 struct inode *inode = page->mapping->host;
645 struct fuse_conn *fc = get_fuse_conn(inode);
646 struct fuse_req *req;
648 loff_t pos = page_offset(page);
649 size_t count = PAGE_CACHE_SIZE;
654 if (is_bad_inode(inode))
658 * Page writeback can extend beyond the lifetime of the
659 * page-cache page, so make sure we read a properly synced
662 fuse_wait_on_page_writeback(inode, page->index);
664 req = fuse_get_req(fc, 1);
669 attr_ver = fuse_get_attr_version(fc);
671 req->out.page_zeroing = 1;
672 req->out.argpages = 1;
674 req->pages[0] = page;
675 req->page_descs[0].length = count;
676 num_read = fuse_send_read(req, &io, pos, count, NULL);
677 err = req->out.h.error;
678 fuse_put_request(fc, req);
682 * Short read means EOF. If file size is larger, truncate it
684 if (num_read < count)
685 fuse_read_update_size(inode, pos + num_read, attr_ver);
687 SetPageUptodate(page);
690 fuse_invalidate_attr(inode); /* atime changed */
696 static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
699 size_t count = req->misc.read.in.size;
700 size_t num_read = req->out.args[0].size;
701 struct address_space *mapping = NULL;
703 for (i = 0; mapping == NULL && i < req->num_pages; i++)
704 mapping = req->pages[i]->mapping;
707 struct inode *inode = mapping->host;
710 * Short read means EOF. If file size is larger, truncate it
712 if (!req->out.h.error && num_read < count) {
715 pos = page_offset(req->pages[0]) + num_read;
716 fuse_read_update_size(inode, pos,
717 req->misc.read.attr_ver);
719 fuse_invalidate_attr(inode); /* atime changed */
722 for (i = 0; i < req->num_pages; i++) {
723 struct page *page = req->pages[i];
724 if (!req->out.h.error)
725 SetPageUptodate(page);
729 page_cache_release(page);
732 fuse_file_put(req->ff, false);
735 static void fuse_send_readpages(struct fuse_req *req, struct file *file)
737 struct fuse_file *ff = file->private_data;
738 struct fuse_conn *fc = ff->fc;
739 loff_t pos = page_offset(req->pages[0]);
740 size_t count = req->num_pages << PAGE_CACHE_SHIFT;
742 req->out.argpages = 1;
743 req->out.page_zeroing = 1;
744 req->out.page_replace = 1;
745 fuse_read_fill(req, file, pos, count, FUSE_READ);
746 req->misc.read.attr_ver = fuse_get_attr_version(fc);
747 if (fc->async_read) {
748 req->ff = fuse_file_get(ff);
749 req->end = fuse_readpages_end;
750 fuse_request_send_background(fc, req);
752 fuse_request_send(fc, req);
753 fuse_readpages_end(fc, req);
754 fuse_put_request(fc, req);
758 struct fuse_fill_data {
759 struct fuse_req *req;
765 static int fuse_readpages_fill(void *_data, struct page *page)
767 struct fuse_fill_data *data = _data;
768 struct fuse_req *req = data->req;
769 struct inode *inode = data->inode;
770 struct fuse_conn *fc = get_fuse_conn(inode);
772 fuse_wait_on_page_writeback(inode, page->index);
774 if (req->num_pages &&
775 (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
776 (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
777 req->pages[req->num_pages - 1]->index + 1 != page->index)) {
778 int nr_alloc = min_t(unsigned, data->nr_pages,
779 FUSE_MAX_PAGES_PER_REQ);
780 fuse_send_readpages(req, data->file);
782 req = fuse_get_req_for_background(fc, nr_alloc);
784 req = fuse_get_req(fc, nr_alloc);
793 if (WARN_ON(req->num_pages >= req->max_pages)) {
794 fuse_put_request(fc, req);
798 page_cache_get(page);
799 req->pages[req->num_pages] = page;
800 req->page_descs[req->num_pages].length = PAGE_SIZE;
806 static int fuse_readpages(struct file *file, struct address_space *mapping,
807 struct list_head *pages, unsigned nr_pages)
809 struct inode *inode = mapping->host;
810 struct fuse_conn *fc = get_fuse_conn(inode);
811 struct fuse_fill_data data;
813 int nr_alloc = min_t(unsigned, nr_pages, FUSE_MAX_PAGES_PER_REQ);
816 if (is_bad_inode(inode))
822 data.req = fuse_get_req_for_background(fc, nr_alloc);
824 data.req = fuse_get_req(fc, nr_alloc);
825 data.nr_pages = nr_pages;
826 err = PTR_ERR(data.req);
827 if (IS_ERR(data.req))
830 err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
832 if (data.req->num_pages)
833 fuse_send_readpages(data.req, file);
835 fuse_put_request(fc, data.req);
841 static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
842 unsigned long nr_segs, loff_t pos)
844 struct inode *inode = iocb->ki_filp->f_mapping->host;
845 struct fuse_conn *fc = get_fuse_conn(inode);
848 * In auto invalidate mode, always update attributes on read.
849 * Otherwise, only update if we attempt to read past EOF (to ensure
850 * i_size is up to date).
852 if (fc->auto_inval_data ||
853 (pos + iov_length(iov, nr_segs) > i_size_read(inode))) {
855 err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL);
860 return generic_file_aio_read(iocb, iov, nr_segs, pos);
863 static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff,
864 loff_t pos, size_t count)
866 struct fuse_write_in *inarg = &req->misc.write.in;
867 struct fuse_write_out *outarg = &req->misc.write.out;
872 req->in.h.opcode = FUSE_WRITE;
873 req->in.h.nodeid = ff->nodeid;
875 if (ff->fc->minor < 9)
876 req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE;
878 req->in.args[0].size = sizeof(struct fuse_write_in);
879 req->in.args[0].value = inarg;
880 req->in.args[1].size = count;
881 req->out.numargs = 1;
882 req->out.args[0].size = sizeof(struct fuse_write_out);
883 req->out.args[0].value = outarg;
886 static size_t fuse_send_write(struct fuse_req *req, struct fuse_io_priv *io,
887 loff_t pos, size_t count, fl_owner_t owner)
889 struct file *file = io->file;
890 struct fuse_file *ff = file->private_data;
891 struct fuse_conn *fc = ff->fc;
892 struct fuse_write_in *inarg = &req->misc.write.in;
894 fuse_write_fill(req, ff, pos, count);
895 inarg->flags = file->f_flags;
897 inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
898 inarg->lock_owner = fuse_lock_owner_id(fc, owner);
902 return fuse_async_req_send(fc, req, count, io);
904 fuse_request_send(fc, req);
905 return req->misc.write.out.size;
908 void fuse_write_update_size(struct inode *inode, loff_t pos)
910 struct fuse_conn *fc = get_fuse_conn(inode);
911 struct fuse_inode *fi = get_fuse_inode(inode);
913 spin_lock(&fc->lock);
914 fi->attr_version = ++fc->attr_version;
915 if (pos > inode->i_size)
916 i_size_write(inode, pos);
917 spin_unlock(&fc->lock);
920 static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
921 struct inode *inode, loff_t pos,
927 struct fuse_io_priv io = { .async = 0, .file = file };
929 for (i = 0; i < req->num_pages; i++)
930 fuse_wait_on_page_writeback(inode, req->pages[i]->index);
932 res = fuse_send_write(req, &io, pos, count, NULL);
934 offset = req->page_descs[0].offset;
936 for (i = 0; i < req->num_pages; i++) {
937 struct page *page = req->pages[i];
939 if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE)
940 SetPageUptodate(page);
942 if (count > PAGE_CACHE_SIZE - offset)
943 count -= PAGE_CACHE_SIZE - offset;
949 page_cache_release(page);
955 static ssize_t fuse_fill_write_pages(struct fuse_req *req,
956 struct address_space *mapping,
957 struct iov_iter *ii, loff_t pos)
959 struct fuse_conn *fc = get_fuse_conn(mapping->host);
960 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
964 req->in.argpages = 1;
965 req->page_descs[0].offset = offset;
970 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
971 size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset,
974 bytes = min_t(size_t, bytes, fc->max_write - count);
978 if (iov_iter_fault_in_readable(ii, bytes))
982 page = grab_cache_page_write_begin(mapping, index, 0);
986 if (mapping_writably_mapped(mapping))
987 flush_dcache_page(page);
990 tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes);
992 flush_dcache_page(page);
994 mark_page_accessed(page);
998 page_cache_release(page);
999 bytes = min(bytes, iov_iter_single_seg_count(ii));
1004 req->pages[req->num_pages] = page;
1005 req->page_descs[req->num_pages].length = tmp;
1008 iov_iter_advance(ii, tmp);
1012 if (offset == PAGE_CACHE_SIZE)
1015 if (!fc->big_writes)
1017 } while (iov_iter_count(ii) && count < fc->max_write &&
1018 req->num_pages < req->max_pages && offset == 0);
1020 return count > 0 ? count : err;
1023 static inline unsigned fuse_wr_pages(loff_t pos, size_t len)
1025 return min_t(unsigned,
1026 ((pos + len - 1) >> PAGE_CACHE_SHIFT) -
1027 (pos >> PAGE_CACHE_SHIFT) + 1,
1028 FUSE_MAX_PAGES_PER_REQ);
1031 static ssize_t fuse_perform_write(struct file *file,
1032 struct address_space *mapping,
1033 struct iov_iter *ii, loff_t pos)
1035 struct inode *inode = mapping->host;
1036 struct fuse_conn *fc = get_fuse_conn(inode);
1037 struct fuse_inode *fi = get_fuse_inode(inode);
1041 if (is_bad_inode(inode))
1044 if (inode->i_size < pos + iov_iter_count(ii))
1045 set_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
1048 struct fuse_req *req;
1050 unsigned nr_pages = fuse_wr_pages(pos, iov_iter_count(ii));
1052 req = fuse_get_req(fc, nr_pages);
1058 count = fuse_fill_write_pages(req, mapping, ii, pos);
1064 num_written = fuse_send_write_pages(req, file, inode,
1066 err = req->out.h.error;
1071 /* break out of the loop on short write */
1072 if (num_written != count)
1076 fuse_put_request(fc, req);
1077 } while (!err && iov_iter_count(ii));
1080 fuse_write_update_size(inode, pos);
1082 clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
1083 fuse_invalidate_attr(inode);
1085 return res > 0 ? res : err;
1088 static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
1089 unsigned long nr_segs, loff_t pos)
1091 struct file *file = iocb->ki_filp;
1092 struct address_space *mapping = file->f_mapping;
1095 ssize_t written = 0;
1096 ssize_t written_buffered = 0;
1097 struct inode *inode = mapping->host;
1102 WARN_ON(iocb->ki_pos != pos);
1105 err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
1110 mutex_lock(&inode->i_mutex);
1112 /* We can write back this queue in page reclaim */
1113 current->backing_dev_info = mapping->backing_dev_info;
1115 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1122 err = file_remove_suid(file);
1126 err = file_update_time(file);
1130 if (file->f_flags & O_DIRECT) {
1131 written = generic_file_direct_write(iocb, iov, &nr_segs,
1134 if (written < 0 || written == count)
1140 iov_iter_init(&i, iov, nr_segs, count, written);
1141 written_buffered = fuse_perform_write(file, mapping, &i, pos);
1142 if (written_buffered < 0) {
1143 err = written_buffered;
1146 endbyte = pos + written_buffered - 1;
1148 err = filemap_write_and_wait_range(file->f_mapping, pos,
1153 invalidate_mapping_pages(file->f_mapping,
1154 pos >> PAGE_CACHE_SHIFT,
1155 endbyte >> PAGE_CACHE_SHIFT);
1157 written += written_buffered;
1158 iocb->ki_pos = pos + written_buffered;
1160 iov_iter_init(&i, iov, nr_segs, count, 0);
1161 written = fuse_perform_write(file, mapping, &i, pos);
1163 iocb->ki_pos = pos + written;
1166 current->backing_dev_info = NULL;
1167 mutex_unlock(&inode->i_mutex);
1169 return written ? written : err;
1172 static inline void fuse_page_descs_length_init(struct fuse_req *req,
1173 unsigned index, unsigned nr_pages)
1177 for (i = index; i < index + nr_pages; i++)
1178 req->page_descs[i].length = PAGE_SIZE -
1179 req->page_descs[i].offset;
1182 static inline unsigned long fuse_get_user_addr(const struct iov_iter *ii)
1184 return (unsigned long)ii->iov->iov_base + ii->iov_offset;
1187 static inline size_t fuse_get_frag_size(const struct iov_iter *ii,
1190 return min(iov_iter_single_seg_count(ii), max_size);
1193 static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
1194 size_t *nbytesp, int write)
1196 size_t nbytes = 0; /* # bytes already packed in req */
1198 /* Special case for kernel I/O: can copy directly into the buffer */
1199 if (segment_eq(get_fs(), KERNEL_DS)) {
1200 unsigned long user_addr = fuse_get_user_addr(ii);
1201 size_t frag_size = fuse_get_frag_size(ii, *nbytesp);
1204 req->in.args[1].value = (void *) user_addr;
1206 req->out.args[0].value = (void *) user_addr;
1208 iov_iter_advance(ii, frag_size);
1209 *nbytesp = frag_size;
1213 while (nbytes < *nbytesp && req->num_pages < req->max_pages) {
1215 unsigned long user_addr = fuse_get_user_addr(ii);
1216 unsigned offset = user_addr & ~PAGE_MASK;
1217 size_t frag_size = fuse_get_frag_size(ii, *nbytesp - nbytes);
1220 unsigned n = req->max_pages - req->num_pages;
1221 frag_size = min_t(size_t, frag_size, n << PAGE_SHIFT);
1223 npages = (frag_size + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
1224 npages = clamp(npages, 1U, n);
1226 ret = get_user_pages_fast(user_addr, npages, !write,
1227 &req->pages[req->num_pages]);
1232 frag_size = min_t(size_t, frag_size,
1233 (npages << PAGE_SHIFT) - offset);
1234 iov_iter_advance(ii, frag_size);
1236 req->page_descs[req->num_pages].offset = offset;
1237 fuse_page_descs_length_init(req, req->num_pages, npages);
1239 req->num_pages += npages;
1240 req->page_descs[req->num_pages - 1].length -=
1241 (npages << PAGE_SHIFT) - offset - frag_size;
1243 nbytes += frag_size;
1247 req->in.argpages = 1;
1249 req->out.argpages = 1;
1256 static inline int fuse_iter_npages(const struct iov_iter *ii_p)
1258 struct iov_iter ii = *ii_p;
1261 while (iov_iter_count(&ii) && npages < FUSE_MAX_PAGES_PER_REQ) {
1262 unsigned long user_addr = fuse_get_user_addr(&ii);
1263 unsigned offset = user_addr & ~PAGE_MASK;
1264 size_t frag_size = iov_iter_single_seg_count(&ii);
1266 npages += (frag_size + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
1267 iov_iter_advance(&ii, frag_size);
1270 return min(npages, FUSE_MAX_PAGES_PER_REQ);
1273 ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
1274 unsigned long nr_segs, size_t count, loff_t *ppos,
1277 struct file *file = io->file;
1278 struct fuse_file *ff = file->private_data;
1279 struct fuse_conn *fc = ff->fc;
1280 size_t nmax = write ? fc->max_write : fc->max_read;
1283 struct fuse_req *req;
1286 iov_iter_init(&ii, iov, nr_segs, count, 0);
1289 req = fuse_get_req_for_background(fc, fuse_iter_npages(&ii));
1291 req = fuse_get_req(fc, fuse_iter_npages(&ii));
1293 return PTR_ERR(req);
1297 fl_owner_t owner = current->files;
1298 size_t nbytes = min(count, nmax);
1299 int err = fuse_get_user_pages(req, &ii, &nbytes, write);
1306 nres = fuse_send_write(req, io, pos, nbytes, owner);
1308 nres = fuse_send_read(req, io, pos, nbytes, owner);
1311 fuse_release_user_pages(req, !write);
1312 if (req->out.h.error) {
1314 res = req->out.h.error;
1316 } else if (nres > nbytes) {
1326 fuse_put_request(fc, req);
1328 req = fuse_get_req_for_background(fc,
1329 fuse_iter_npages(&ii));
1331 req = fuse_get_req(fc, fuse_iter_npages(&ii));
1337 fuse_put_request(fc, req);
1343 EXPORT_SYMBOL_GPL(fuse_direct_io);
1345 static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
1346 const struct iovec *iov,
1347 unsigned long nr_segs, loff_t *ppos,
1351 struct file *file = io->file;
1352 struct inode *inode = file_inode(file);
1354 if (is_bad_inode(inode))
1357 res = fuse_direct_io(io, iov, nr_segs, count, ppos, 0);
1359 fuse_invalidate_attr(inode);
1364 static ssize_t fuse_direct_read(struct file *file, char __user *buf,
1365 size_t count, loff_t *ppos)
1367 struct fuse_io_priv io = { .async = 0, .file = file };
1368 struct iovec iov = { .iov_base = buf, .iov_len = count };
1369 return __fuse_direct_read(&io, &iov, 1, ppos, count);
1372 static ssize_t __fuse_direct_write(struct fuse_io_priv *io,
1373 const struct iovec *iov,
1374 unsigned long nr_segs, loff_t *ppos)
1376 struct file *file = io->file;
1377 struct inode *inode = file_inode(file);
1378 size_t count = iov_length(iov, nr_segs);
1381 res = generic_write_checks(file, ppos, &count, 0);
1383 res = fuse_direct_io(io, iov, nr_segs, count, ppos, 1);
1385 fuse_invalidate_attr(inode);
1390 static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
1391 size_t count, loff_t *ppos)
1393 struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = count };
1394 struct inode *inode = file_inode(file);
1396 struct fuse_io_priv io = { .async = 0, .file = file };
1398 if (is_bad_inode(inode))
1401 /* Don't allow parallel writes to the same file */
1402 mutex_lock(&inode->i_mutex);
1403 res = __fuse_direct_write(&io, &iov, 1, ppos);
1405 fuse_write_update_size(inode, *ppos);
1406 mutex_unlock(&inode->i_mutex);
1411 static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
1415 for (i = 0; i < req->num_pages; i++)
1416 __free_page(req->pages[i]);
1419 fuse_file_put(req->ff, false);
1422 static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req)
1424 struct inode *inode = req->inode;
1425 struct fuse_inode *fi = get_fuse_inode(inode);
1426 struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info;
1429 list_del(&req->writepages_entry);
1430 for (i = 0; i < req->num_pages; i++) {
1431 dec_bdi_stat(bdi, BDI_WRITEBACK);
1432 dec_zone_page_state(req->pages[i], NR_WRITEBACK_TEMP);
1433 bdi_writeout_inc(bdi);
1435 wake_up(&fi->page_waitq);
1438 /* Called under fc->lock, may release and reacquire it */
1439 static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req)
1440 __releases(fc->lock)
1441 __acquires(fc->lock)
1443 struct fuse_inode *fi = get_fuse_inode(req->inode);
1444 loff_t size = i_size_read(req->inode);
1445 struct fuse_write_in *inarg = &req->misc.write.in;
1446 __u64 data_size = req->num_pages * PAGE_CACHE_SIZE;
1451 if (inarg->offset + data_size <= size) {
1452 inarg->size = data_size;
1453 } else if (inarg->offset < size) {
1454 inarg->size = size - inarg->offset;
1456 /* Got truncated off completely */
1460 req->in.args[1].size = inarg->size;
1462 fuse_request_send_background_locked(fc, req);
1466 fuse_writepage_finish(fc, req);
1467 spin_unlock(&fc->lock);
1468 fuse_writepage_free(fc, req);
1469 fuse_put_request(fc, req);
1470 spin_lock(&fc->lock);
1474 * If fi->writectr is positive (no truncate or fsync going on) send
1475 * all queued writepage requests.
1477 * Called with fc->lock
1479 void fuse_flush_writepages(struct inode *inode)
1480 __releases(fc->lock)
1481 __acquires(fc->lock)
1483 struct fuse_conn *fc = get_fuse_conn(inode);
1484 struct fuse_inode *fi = get_fuse_inode(inode);
1485 struct fuse_req *req;
1487 while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) {
1488 req = list_entry(fi->queued_writes.next, struct fuse_req, list);
1489 list_del_init(&req->list);
1490 fuse_send_writepage(fc, req);
1494 static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req)
1496 struct inode *inode = req->inode;
1497 struct fuse_inode *fi = get_fuse_inode(inode);
1499 mapping_set_error(inode->i_mapping, req->out.h.error);
1500 spin_lock(&fc->lock);
1501 while (req->misc.write.next) {
1502 struct fuse_req *next = req->misc.write.next;
1503 req->misc.write.next = next->misc.write.next;
1504 next->misc.write.next = NULL;
1505 list_add(&next->writepages_entry, &fi->writepages);
1506 list_add_tail(&next->list, &fi->queued_writes);
1507 fuse_flush_writepages(inode);
1510 fuse_writepage_finish(fc, req);
1511 spin_unlock(&fc->lock);
1512 fuse_writepage_free(fc, req);
1515 static struct fuse_file *fuse_write_file_get(struct fuse_conn *fc,
1516 struct fuse_inode *fi)
1518 struct fuse_file *ff = NULL;
1520 spin_lock(&fc->lock);
1521 if (!WARN_ON(list_empty(&fi->write_files))) {
1522 ff = list_entry(fi->write_files.next, struct fuse_file,
1526 spin_unlock(&fc->lock);
1531 static int fuse_writepage_locked(struct page *page)
1533 struct address_space *mapping = page->mapping;
1534 struct inode *inode = mapping->host;
1535 struct fuse_conn *fc = get_fuse_conn(inode);
1536 struct fuse_inode *fi = get_fuse_inode(inode);
1537 struct fuse_req *req;
1538 struct page *tmp_page;
1539 int error = -ENOMEM;
1541 set_page_writeback(page);
1543 req = fuse_request_alloc_nofs(1);
1547 req->background = 1; /* writeback always goes to bg_queue */
1548 tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
1553 req->ff = fuse_write_file_get(fc, fi);
1557 fuse_write_fill(req, req->ff, page_offset(page), 0);
1559 copy_highpage(tmp_page, page);
1560 req->misc.write.in.write_flags |= FUSE_WRITE_CACHE;
1561 req->misc.write.next = NULL;
1562 req->in.argpages = 1;
1564 req->pages[0] = tmp_page;
1565 req->page_descs[0].offset = 0;
1566 req->page_descs[0].length = PAGE_SIZE;
1567 req->end = fuse_writepage_end;
1570 inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK);
1571 inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP);
1573 spin_lock(&fc->lock);
1574 list_add(&req->writepages_entry, &fi->writepages);
1575 list_add_tail(&req->list, &fi->queued_writes);
1576 fuse_flush_writepages(inode);
1577 spin_unlock(&fc->lock);
1579 end_page_writeback(page);
1584 fuse_request_free(req);
1586 end_page_writeback(page);
1590 static int fuse_writepage(struct page *page, struct writeback_control *wbc)
1594 if (fuse_page_is_writeback(page->mapping->host, page->index)) {
1596 * ->writepages() should be called for sync() and friends. We
1597 * should only get here on direct reclaim and then we are
1598 * allowed to skip a page which is already in flight
1600 WARN_ON(wbc->sync_mode == WB_SYNC_ALL);
1602 redirty_page_for_writepage(wbc, page);
1606 err = fuse_writepage_locked(page);
1612 struct fuse_fill_wb_data {
1613 struct fuse_req *req;
1614 struct fuse_file *ff;
1615 struct inode *inode;
1616 struct page **orig_pages;
1619 static void fuse_writepages_send(struct fuse_fill_wb_data *data)
1621 struct fuse_req *req = data->req;
1622 struct inode *inode = data->inode;
1623 struct fuse_conn *fc = get_fuse_conn(inode);
1624 struct fuse_inode *fi = get_fuse_inode(inode);
1625 int num_pages = req->num_pages;
1628 req->ff = fuse_file_get(data->ff);
1629 spin_lock(&fc->lock);
1630 list_add_tail(&req->list, &fi->queued_writes);
1631 fuse_flush_writepages(inode);
1632 spin_unlock(&fc->lock);
1634 for (i = 0; i < num_pages; i++)
1635 end_page_writeback(data->orig_pages[i]);
1638 static bool fuse_writepage_in_flight(struct fuse_req *new_req,
1641 struct fuse_conn *fc = get_fuse_conn(new_req->inode);
1642 struct fuse_inode *fi = get_fuse_inode(new_req->inode);
1643 struct fuse_req *tmp;
1644 struct fuse_req *old_req;
1648 BUG_ON(new_req->num_pages != 0);
1650 spin_lock(&fc->lock);
1651 list_del(&new_req->writepages_entry);
1652 new_req->num_pages = 1;
1653 list_for_each_entry(old_req, &fi->writepages, writepages_entry) {
1654 BUG_ON(old_req->inode != new_req->inode);
1655 curr_index = old_req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
1656 if (curr_index <= page->index &&
1657 page->index < curr_index + old_req->num_pages) {
1665 for (tmp = old_req; tmp != NULL; tmp = tmp->misc.write.next) {
1666 BUG_ON(tmp->inode != new_req->inode);
1667 curr_index = tmp->misc.write.in.offset >> PAGE_CACHE_SHIFT;
1668 if (tmp->num_pages == 1 &&
1669 curr_index == page->index) {
1674 if (old_req->num_pages == 1 && (old_req->state == FUSE_REQ_INIT ||
1675 old_req->state == FUSE_REQ_PENDING)) {
1676 copy_highpage(old_req->pages[0], page);
1677 spin_unlock(&fc->lock);
1679 dec_bdi_stat(page->mapping->backing_dev_info, BDI_WRITEBACK);
1680 dec_zone_page_state(page, NR_WRITEBACK_TEMP);
1681 fuse_writepage_free(fc, new_req);
1682 fuse_request_free(new_req);
1685 new_req->misc.write.next = old_req->misc.write.next;
1686 old_req->misc.write.next = new_req;
1689 spin_unlock(&fc->lock);
1694 static int fuse_writepages_fill(struct page *page,
1695 struct writeback_control *wbc, void *_data)
1697 struct fuse_fill_wb_data *data = _data;
1698 struct fuse_req *req = data->req;
1699 struct inode *inode = data->inode;
1700 struct fuse_conn *fc = get_fuse_conn(inode);
1701 struct page *tmp_page;
1707 data->ff = fuse_write_file_get(fc, get_fuse_inode(inode));
1713 * Being under writeback is unlikely but possible. For example direct
1714 * read to an mmaped fuse file will set the page dirty twice; once when
1715 * the pages are faulted with get_user_pages(), and then after the read
1718 is_writeback = fuse_page_is_writeback(inode, page->index);
1720 if (req && req->num_pages &&
1721 (is_writeback || req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
1722 (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_write ||
1723 data->orig_pages[req->num_pages - 1]->index + 1 != page->index)) {
1724 fuse_writepages_send(data);
1728 tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
1733 * The page must not be redirtied until the writeout is completed
1734 * (i.e. userspace has sent a reply to the write request). Otherwise
1735 * there could be more than one temporary page instance for each real
1738 * This is ensured by holding the page lock in page_mkwrite() while
1739 * checking fuse_page_is_writeback(). We already hold the page lock
1740 * since clear_page_dirty_for_io() and keep it held until we add the
1741 * request to the fi->writepages list and increment req->num_pages.
1742 * After this fuse_page_is_writeback() will indicate that the page is
1743 * under writeback, so we can release the page lock.
1745 if (data->req == NULL) {
1746 struct fuse_inode *fi = get_fuse_inode(inode);
1749 req = fuse_request_alloc_nofs(FUSE_MAX_PAGES_PER_REQ);
1751 __free_page(tmp_page);
1755 fuse_write_fill(req, data->ff, page_offset(page), 0);
1756 req->misc.write.in.write_flags |= FUSE_WRITE_CACHE;
1757 req->misc.write.next = NULL;
1758 req->in.argpages = 1;
1759 req->background = 1;
1761 req->end = fuse_writepage_end;
1764 spin_lock(&fc->lock);
1765 list_add(&req->writepages_entry, &fi->writepages);
1766 spin_unlock(&fc->lock);
1770 set_page_writeback(page);
1772 copy_highpage(tmp_page, page);
1773 req->pages[req->num_pages] = tmp_page;
1774 req->page_descs[req->num_pages].offset = 0;
1775 req->page_descs[req->num_pages].length = PAGE_SIZE;
1777 inc_bdi_stat(page->mapping->backing_dev_info, BDI_WRITEBACK);
1778 inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP);
1781 if (is_writeback && fuse_writepage_in_flight(req, page)) {
1782 end_page_writeback(page);
1786 data->orig_pages[req->num_pages] = page;
1789 * Protected by fc->lock against concurrent access by
1790 * fuse_page_is_writeback().
1792 spin_lock(&fc->lock);
1794 spin_unlock(&fc->lock);
1802 static int fuse_writepages(struct address_space *mapping,
1803 struct writeback_control *wbc)
1805 struct inode *inode = mapping->host;
1806 struct fuse_fill_wb_data data;
1810 if (is_bad_inode(inode))
1818 data.orig_pages = kzalloc(sizeof(struct page *) *
1819 FUSE_MAX_PAGES_PER_REQ,
1821 if (!data.orig_pages)
1824 err = write_cache_pages(mapping, wbc, fuse_writepages_fill, &data);
1826 /* Ignore errors if we can write at least one page */
1827 BUG_ON(!data.req->num_pages);
1828 fuse_writepages_send(&data);
1832 fuse_file_put(data.ff, false);
1834 kfree(data.orig_pages);
1839 static int fuse_launder_page(struct page *page)
1842 if (clear_page_dirty_for_io(page)) {
1843 struct inode *inode = page->mapping->host;
1844 err = fuse_writepage_locked(page);
1846 fuse_wait_on_page_writeback(inode, page->index);
1852 * Write back dirty pages now, because there may not be any suitable
1855 static void fuse_vma_close(struct vm_area_struct *vma)
1857 filemap_write_and_wait(vma->vm_file->f_mapping);
1861 * Wait for writeback against this page to complete before allowing it
1862 * to be marked dirty again, and hence written back again, possibly
1863 * before the previous writepage completed.
1865 * Block here, instead of in ->writepage(), so that the userspace fs
1866 * can only block processes actually operating on the filesystem.
1868 * Otherwise unprivileged userspace fs would be able to block
1873 * - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER
1875 static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
1877 struct page *page = vmf->page;
1878 struct inode *inode = file_inode(vma->vm_file);
1880 file_update_time(vma->vm_file);
1882 if (page->mapping != inode->i_mapping) {
1884 return VM_FAULT_NOPAGE;
1887 fuse_wait_on_page_writeback(inode, page->index);
1888 return VM_FAULT_LOCKED;
1891 static const struct vm_operations_struct fuse_file_vm_ops = {
1892 .close = fuse_vma_close,
1893 .fault = filemap_fault,
1894 .page_mkwrite = fuse_page_mkwrite,
1895 .remap_pages = generic_file_remap_pages,
1898 static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
1900 if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) {
1901 struct inode *inode = file_inode(file);
1902 struct fuse_conn *fc = get_fuse_conn(inode);
1903 struct fuse_inode *fi = get_fuse_inode(inode);
1904 struct fuse_file *ff = file->private_data;
1906 * file may be written through mmap, so chain it onto the
1907 * inodes's write_file list
1909 spin_lock(&fc->lock);
1910 if (list_empty(&ff->write_entry))
1911 list_add(&ff->write_entry, &fi->write_files);
1912 spin_unlock(&fc->lock);
1914 file_accessed(file);
1915 vma->vm_ops = &fuse_file_vm_ops;
1919 static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma)
1921 /* Can't provide the coherency needed for MAP_SHARED */
1922 if (vma->vm_flags & VM_MAYSHARE)
1925 invalidate_inode_pages2(file->f_mapping);
1927 return generic_file_mmap(file, vma);
1930 static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
1931 struct file_lock *fl)
1933 switch (ffl->type) {
1939 if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX ||
1940 ffl->end < ffl->start)
1943 fl->fl_start = ffl->start;
1944 fl->fl_end = ffl->end;
1945 fl->fl_pid = ffl->pid;
1951 fl->fl_type = ffl->type;
1955 static void fuse_lk_fill(struct fuse_req *req, struct file *file,
1956 const struct file_lock *fl, int opcode, pid_t pid,
1959 struct inode *inode = file_inode(file);
1960 struct fuse_conn *fc = get_fuse_conn(inode);
1961 struct fuse_file *ff = file->private_data;
1962 struct fuse_lk_in *arg = &req->misc.lk_in;
1965 arg->owner = fuse_lock_owner_id(fc, fl->fl_owner);
1966 arg->lk.start = fl->fl_start;
1967 arg->lk.end = fl->fl_end;
1968 arg->lk.type = fl->fl_type;
1971 arg->lk_flags |= FUSE_LK_FLOCK;
1972 req->in.h.opcode = opcode;
1973 req->in.h.nodeid = get_node_id(inode);
1974 req->in.numargs = 1;
1975 req->in.args[0].size = sizeof(*arg);
1976 req->in.args[0].value = arg;
1979 static int fuse_getlk(struct file *file, struct file_lock *fl)
1981 struct inode *inode = file_inode(file);
1982 struct fuse_conn *fc = get_fuse_conn(inode);
1983 struct fuse_req *req;
1984 struct fuse_lk_out outarg;
1987 req = fuse_get_req_nopages(fc);
1989 return PTR_ERR(req);
1991 fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0);
1992 req->out.numargs = 1;
1993 req->out.args[0].size = sizeof(outarg);
1994 req->out.args[0].value = &outarg;
1995 fuse_request_send(fc, req);
1996 err = req->out.h.error;
1997 fuse_put_request(fc, req);
1999 err = convert_fuse_file_lock(&outarg.lk, fl);
2004 static int fuse_setlk(struct file *file, struct file_lock *fl, int flock)
2006 struct inode *inode = file_inode(file);
2007 struct fuse_conn *fc = get_fuse_conn(inode);
2008 struct fuse_req *req;
2009 int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
2010 pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
2013 if (fl->fl_lmops && fl->fl_lmops->lm_grant) {
2014 /* NLM needs asynchronous locks, which we don't support yet */
2018 /* Unlock on close is handled by the flush method */
2019 if (fl->fl_flags & FL_CLOSE)
2022 req = fuse_get_req_nopages(fc);
2024 return PTR_ERR(req);
2026 fuse_lk_fill(req, file, fl, opcode, pid, flock);
2027 fuse_request_send(fc, req);
2028 err = req->out.h.error;
2029 /* locking is restartable */
2032 fuse_put_request(fc, req);
2036 static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
2038 struct inode *inode = file_inode(file);
2039 struct fuse_conn *fc = get_fuse_conn(inode);
2042 if (cmd == F_CANCELLK) {
2044 } else if (cmd == F_GETLK) {
2046 posix_test_lock(file, fl);
2049 err = fuse_getlk(file, fl);
2052 err = posix_lock_file(file, fl, NULL);
2054 err = fuse_setlk(file, fl, 0);
2059 static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl)
2061 struct inode *inode = file_inode(file);
2062 struct fuse_conn *fc = get_fuse_conn(inode);
2066 err = flock_lock_file_wait(file, fl);
2068 struct fuse_file *ff = file->private_data;
2070 /* emulate flock with POSIX locks */
2071 fl->fl_owner = (fl_owner_t) file;
2073 err = fuse_setlk(file, fl, 1);
2079 static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
2081 struct inode *inode = mapping->host;
2082 struct fuse_conn *fc = get_fuse_conn(inode);
2083 struct fuse_req *req;
2084 struct fuse_bmap_in inarg;
2085 struct fuse_bmap_out outarg;
2088 if (!inode->i_sb->s_bdev || fc->no_bmap)
2091 req = fuse_get_req_nopages(fc);
2095 memset(&inarg, 0, sizeof(inarg));
2096 inarg.block = block;
2097 inarg.blocksize = inode->i_sb->s_blocksize;
2098 req->in.h.opcode = FUSE_BMAP;
2099 req->in.h.nodeid = get_node_id(inode);
2100 req->in.numargs = 1;
2101 req->in.args[0].size = sizeof(inarg);
2102 req->in.args[0].value = &inarg;
2103 req->out.numargs = 1;
2104 req->out.args[0].size = sizeof(outarg);
2105 req->out.args[0].value = &outarg;
2106 fuse_request_send(fc, req);
2107 err = req->out.h.error;
2108 fuse_put_request(fc, req);
2112 return err ? 0 : outarg.block;
2115 static loff_t fuse_file_llseek(struct file *file, loff_t offset, int whence)
2118 struct inode *inode = file_inode(file);
2120 /* No i_mutex protection necessary for SEEK_CUR and SEEK_SET */
2121 if (whence == SEEK_CUR || whence == SEEK_SET)
2122 return generic_file_llseek(file, offset, whence);
2124 mutex_lock(&inode->i_mutex);
2125 retval = fuse_update_attributes(inode, NULL, file, NULL);
2127 retval = generic_file_llseek(file, offset, whence);
2128 mutex_unlock(&inode->i_mutex);
2133 static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov,
2134 unsigned int nr_segs, size_t bytes, bool to_user)
2142 iov_iter_init(&ii, iov, nr_segs, bytes, 0);
2144 while (iov_iter_count(&ii)) {
2145 struct page *page = pages[page_idx++];
2146 size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii));
2152 char __user *uaddr = ii.iov->iov_base + ii.iov_offset;
2153 size_t iov_len = ii.iov->iov_len - ii.iov_offset;
2154 size_t copy = min(todo, iov_len);
2158 left = copy_from_user(kaddr, uaddr, copy);
2160 left = copy_to_user(uaddr, kaddr, copy);
2165 iov_iter_advance(&ii, copy);
2177 * CUSE servers compiled on 32bit broke on 64bit kernels because the
2178 * ABI was defined to be 'struct iovec' which is different on 32bit
2179 * and 64bit. Fortunately we can determine which structure the server
2180 * used from the size of the reply.
2182 static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src,
2183 size_t transferred, unsigned count,
2186 #ifdef CONFIG_COMPAT
2187 if (count * sizeof(struct compat_iovec) == transferred) {
2188 struct compat_iovec *ciov = src;
2192 * With this interface a 32bit server cannot support
2193 * non-compat (i.e. ones coming from 64bit apps) ioctl
2199 for (i = 0; i < count; i++) {
2200 dst[i].iov_base = compat_ptr(ciov[i].iov_base);
2201 dst[i].iov_len = ciov[i].iov_len;
2207 if (count * sizeof(struct iovec) != transferred)
2210 memcpy(dst, src, transferred);
2214 /* Make sure iov_length() won't overflow */
2215 static int fuse_verify_ioctl_iov(struct iovec *iov, size_t count)
2218 u32 max = FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT;
2220 for (n = 0; n < count; n++, iov++) {
2221 if (iov->iov_len > (size_t) max)
2223 max -= iov->iov_len;
2228 static int fuse_copy_ioctl_iovec(struct fuse_conn *fc, struct iovec *dst,
2229 void *src, size_t transferred, unsigned count,
2233 struct fuse_ioctl_iovec *fiov = src;
2235 if (fc->minor < 16) {
2236 return fuse_copy_ioctl_iovec_old(dst, src, transferred,
2240 if (count * sizeof(struct fuse_ioctl_iovec) != transferred)
2243 for (i = 0; i < count; i++) {
2244 /* Did the server supply an inappropriate value? */
2245 if (fiov[i].base != (unsigned long) fiov[i].base ||
2246 fiov[i].len != (unsigned long) fiov[i].len)
2249 dst[i].iov_base = (void __user *) (unsigned long) fiov[i].base;
2250 dst[i].iov_len = (size_t) fiov[i].len;
2252 #ifdef CONFIG_COMPAT
2254 (ptr_to_compat(dst[i].iov_base) != fiov[i].base ||
2255 (compat_size_t) dst[i].iov_len != fiov[i].len))
2265 * For ioctls, there is no generic way to determine how much memory
2266 * needs to be read and/or written. Furthermore, ioctls are allowed
2267 * to dereference the passed pointer, so the parameter requires deep
2268 * copying but FUSE has no idea whatsoever about what to copy in or
2271 * This is solved by allowing FUSE server to retry ioctl with
2272 * necessary in/out iovecs. Let's assume the ioctl implementation
2273 * needs to read in the following structure.
2280 * On the first callout to FUSE server, inarg->in_size and
2281 * inarg->out_size will be NULL; then, the server completes the ioctl
2282 * with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and
2283 * the actual iov array to
2285 * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } }
2287 * which tells FUSE to copy in the requested area and retry the ioctl.
2288 * On the second round, the server has access to the structure and
2289 * from that it can tell what to look for next, so on the invocation,
2290 * it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to
2292 * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) },
2293 * { .iov_base = a.buf, .iov_len = a.buflen } }
2295 * FUSE will copy both struct a and the pointed buffer from the
2296 * process doing the ioctl and retry ioctl with both struct a and the
2299 * This time, FUSE server has everything it needs and completes ioctl
2300 * without FUSE_IOCTL_RETRY which finishes the ioctl call.
2302 * Copying data out works the same way.
2304 * Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel
2305 * automatically initializes in and out iovs by decoding @cmd with
2306 * _IOC_* macros and the server is not allowed to request RETRY. This
2307 * limits ioctl data transfers to well-formed ioctls and is the forced
2308 * behavior for all FUSE servers.
2310 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
2313 struct fuse_file *ff = file->private_data;
2314 struct fuse_conn *fc = ff->fc;
2315 struct fuse_ioctl_in inarg = {
2321 struct fuse_ioctl_out outarg;
2322 struct fuse_req *req = NULL;
2323 struct page **pages = NULL;
2324 struct iovec *iov_page = NULL;
2325 struct iovec *in_iov = NULL, *out_iov = NULL;
2326 unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages;
2327 size_t in_size, out_size, transferred;
2330 #if BITS_PER_LONG == 32
2331 inarg.flags |= FUSE_IOCTL_32BIT;
2333 if (flags & FUSE_IOCTL_COMPAT)
2334 inarg.flags |= FUSE_IOCTL_32BIT;
2337 /* assume all the iovs returned by client always fits in a page */
2338 BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
2341 pages = kcalloc(FUSE_MAX_PAGES_PER_REQ, sizeof(pages[0]), GFP_KERNEL);
2342 iov_page = (struct iovec *) __get_free_page(GFP_KERNEL);
2343 if (!pages || !iov_page)
2347 * If restricted, initialize IO parameters as encoded in @cmd.
2348 * RETRY from server is not allowed.
2350 if (!(flags & FUSE_IOCTL_UNRESTRICTED)) {
2351 struct iovec *iov = iov_page;
2353 iov->iov_base = (void __user *)arg;
2354 iov->iov_len = _IOC_SIZE(cmd);
2356 if (_IOC_DIR(cmd) & _IOC_WRITE) {
2361 if (_IOC_DIR(cmd) & _IOC_READ) {
2368 inarg.in_size = in_size = iov_length(in_iov, in_iovs);
2369 inarg.out_size = out_size = iov_length(out_iov, out_iovs);
2372 * Out data can be used either for actual out data or iovs,
2373 * make sure there always is at least one page.
2375 out_size = max_t(size_t, out_size, PAGE_SIZE);
2376 max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE);
2378 /* make sure there are enough buffer pages and init request with them */
2380 if (max_pages > FUSE_MAX_PAGES_PER_REQ)
2382 while (num_pages < max_pages) {
2383 pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
2384 if (!pages[num_pages])
2389 req = fuse_get_req(fc, num_pages);
2395 memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages);
2396 req->num_pages = num_pages;
2397 fuse_page_descs_length_init(req, 0, req->num_pages);
2399 /* okay, let's send it to the client */
2400 req->in.h.opcode = FUSE_IOCTL;
2401 req->in.h.nodeid = ff->nodeid;
2402 req->in.numargs = 1;
2403 req->in.args[0].size = sizeof(inarg);
2404 req->in.args[0].value = &inarg;
2407 req->in.args[1].size = in_size;
2408 req->in.argpages = 1;
2410 err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size,
2416 req->out.numargs = 2;
2417 req->out.args[0].size = sizeof(outarg);
2418 req->out.args[0].value = &outarg;
2419 req->out.args[1].size = out_size;
2420 req->out.argpages = 1;
2421 req->out.argvar = 1;
2423 fuse_request_send(fc, req);
2424 err = req->out.h.error;
2425 transferred = req->out.args[1].size;
2426 fuse_put_request(fc, req);
2431 /* did it ask for retry? */
2432 if (outarg.flags & FUSE_IOCTL_RETRY) {
2435 /* no retry if in restricted mode */
2437 if (!(flags & FUSE_IOCTL_UNRESTRICTED))
2440 in_iovs = outarg.in_iovs;
2441 out_iovs = outarg.out_iovs;
2444 * Make sure things are in boundary, separate checks
2445 * are to protect against overflow.
2448 if (in_iovs > FUSE_IOCTL_MAX_IOV ||
2449 out_iovs > FUSE_IOCTL_MAX_IOV ||
2450 in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
2453 vaddr = kmap_atomic(pages[0]);
2454 err = fuse_copy_ioctl_iovec(fc, iov_page, vaddr,
2455 transferred, in_iovs + out_iovs,
2456 (flags & FUSE_IOCTL_COMPAT) != 0);
2457 kunmap_atomic(vaddr);
2462 out_iov = in_iov + in_iovs;
2464 err = fuse_verify_ioctl_iov(in_iov, in_iovs);
2468 err = fuse_verify_ioctl_iov(out_iov, out_iovs);
2476 if (transferred > inarg.out_size)
2479 err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true);
2482 fuse_put_request(fc, req);
2483 free_page((unsigned long) iov_page);
2485 __free_page(pages[--num_pages]);
2488 return err ? err : outarg.result;
2490 EXPORT_SYMBOL_GPL(fuse_do_ioctl);
2492 long fuse_ioctl_common(struct file *file, unsigned int cmd,
2493 unsigned long arg, unsigned int flags)
2495 struct inode *inode = file_inode(file);
2496 struct fuse_conn *fc = get_fuse_conn(inode);
2498 if (!fuse_allow_current_process(fc))
2501 if (is_bad_inode(inode))
2504 return fuse_do_ioctl(file, cmd, arg, flags);
2507 static long fuse_file_ioctl(struct file *file, unsigned int cmd,
2510 return fuse_ioctl_common(file, cmd, arg, 0);
2513 static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
2516 return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT);
2520 * All files which have been polled are linked to RB tree
2521 * fuse_conn->polled_files which is indexed by kh. Walk the tree and
2522 * find the matching one.
2524 static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh,
2525 struct rb_node **parent_out)
2527 struct rb_node **link = &fc->polled_files.rb_node;
2528 struct rb_node *last = NULL;
2531 struct fuse_file *ff;
2534 ff = rb_entry(last, struct fuse_file, polled_node);
2537 link = &last->rb_left;
2538 else if (kh > ff->kh)
2539 link = &last->rb_right;
2550 * The file is about to be polled. Make sure it's on the polled_files
2551 * RB tree. Note that files once added to the polled_files tree are
2552 * not removed before the file is released. This is because a file
2553 * polled once is likely to be polled again.
2555 static void fuse_register_polled_file(struct fuse_conn *fc,
2556 struct fuse_file *ff)
2558 spin_lock(&fc->lock);
2559 if (RB_EMPTY_NODE(&ff->polled_node)) {
2560 struct rb_node **link, *parent;
2562 link = fuse_find_polled_node(fc, ff->kh, &parent);
2564 rb_link_node(&ff->polled_node, parent, link);
2565 rb_insert_color(&ff->polled_node, &fc->polled_files);
2567 spin_unlock(&fc->lock);
2570 unsigned fuse_file_poll(struct file *file, poll_table *wait)
2572 struct fuse_file *ff = file->private_data;
2573 struct fuse_conn *fc = ff->fc;
2574 struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh };
2575 struct fuse_poll_out outarg;
2576 struct fuse_req *req;
2580 return DEFAULT_POLLMASK;
2582 poll_wait(file, &ff->poll_wait, wait);
2583 inarg.events = (__u32)poll_requested_events(wait);
2586 * Ask for notification iff there's someone waiting for it.
2587 * The client may ignore the flag and always notify.
2589 if (waitqueue_active(&ff->poll_wait)) {
2590 inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY;
2591 fuse_register_polled_file(fc, ff);
2594 req = fuse_get_req_nopages(fc);
2598 req->in.h.opcode = FUSE_POLL;
2599 req->in.h.nodeid = ff->nodeid;
2600 req->in.numargs = 1;
2601 req->in.args[0].size = sizeof(inarg);
2602 req->in.args[0].value = &inarg;
2603 req->out.numargs = 1;
2604 req->out.args[0].size = sizeof(outarg);
2605 req->out.args[0].value = &outarg;
2606 fuse_request_send(fc, req);
2607 err = req->out.h.error;
2608 fuse_put_request(fc, req);
2611 return outarg.revents;
2612 if (err == -ENOSYS) {
2614 return DEFAULT_POLLMASK;
2618 EXPORT_SYMBOL_GPL(fuse_file_poll);
2621 * This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and
2622 * wakes up the poll waiters.
2624 int fuse_notify_poll_wakeup(struct fuse_conn *fc,
2625 struct fuse_notify_poll_wakeup_out *outarg)
2627 u64 kh = outarg->kh;
2628 struct rb_node **link;
2630 spin_lock(&fc->lock);
2632 link = fuse_find_polled_node(fc, kh, NULL);
2634 struct fuse_file *ff;
2636 ff = rb_entry(*link, struct fuse_file, polled_node);
2637 wake_up_interruptible_sync(&ff->poll_wait);
2640 spin_unlock(&fc->lock);
2644 static void fuse_do_truncate(struct file *file)
2646 struct inode *inode = file->f_mapping->host;
2649 attr.ia_valid = ATTR_SIZE;
2650 attr.ia_size = i_size_read(inode);
2652 attr.ia_file = file;
2653 attr.ia_valid |= ATTR_FILE;
2655 fuse_do_setattr(inode, &attr, file);
2658 static inline loff_t fuse_round_up(loff_t off)
2660 return round_up(off, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
2664 fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
2665 loff_t offset, unsigned long nr_segs)
2668 struct file *file = iocb->ki_filp;
2669 struct fuse_file *ff = file->private_data;
2670 bool async_dio = ff->fc->async_dio;
2672 struct inode *inode;
2674 size_t count = iov_length(iov, nr_segs);
2675 struct fuse_io_priv *io;
2678 inode = file->f_mapping->host;
2679 i_size = i_size_read(inode);
2681 /* optimization for short read */
2682 if (async_dio && rw != WRITE && offset + count > i_size) {
2683 if (offset >= i_size)
2685 count = min_t(loff_t, count, fuse_round_up(i_size - offset));
2688 io = kmalloc(sizeof(struct fuse_io_priv), GFP_KERNEL);
2691 spin_lock_init(&io->lock);
2695 io->offset = offset;
2696 io->write = (rw == WRITE);
2700 * By default, we want to optimize all I/Os with async request
2701 * submission to the client filesystem if supported.
2703 io->async = async_dio;
2707 * We cannot asynchronously extend the size of a file. We have no method
2708 * to wait on real async I/O requests, so we must submit this request
2711 if (!is_sync_kiocb(iocb) && (offset + count > i_size) && rw == WRITE)
2715 ret = __fuse_direct_write(io, iov, nr_segs, &pos);
2717 ret = __fuse_direct_read(io, iov, nr_segs, &pos, count);
2720 fuse_aio_complete(io, ret < 0 ? ret : 0, -1);
2722 /* we have a non-extending, async request, so return */
2723 if (!is_sync_kiocb(iocb))
2724 return -EIOCBQUEUED;
2726 ret = wait_on_sync_kiocb(iocb);
2733 fuse_write_update_size(inode, pos);
2734 else if (ret < 0 && offset + count > i_size)
2735 fuse_do_truncate(file);
2741 static long fuse_file_fallocate(struct file *file, int mode, loff_t offset,
2744 struct fuse_file *ff = file->private_data;
2745 struct inode *inode = file->f_inode;
2746 struct fuse_inode *fi = get_fuse_inode(inode);
2747 struct fuse_conn *fc = ff->fc;
2748 struct fuse_req *req;
2749 struct fuse_fallocate_in inarg = {
2756 bool lock_inode = !(mode & FALLOC_FL_KEEP_SIZE) ||
2757 (mode & FALLOC_FL_PUNCH_HOLE);
2759 if (fc->no_fallocate)
2763 mutex_lock(&inode->i_mutex);
2764 if (mode & FALLOC_FL_PUNCH_HOLE) {
2765 loff_t endbyte = offset + length - 1;
2766 err = filemap_write_and_wait_range(inode->i_mapping,
2771 fuse_sync_writes(inode);
2775 if (!(mode & FALLOC_FL_KEEP_SIZE))
2776 set_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
2778 req = fuse_get_req_nopages(fc);
2784 req->in.h.opcode = FUSE_FALLOCATE;
2785 req->in.h.nodeid = ff->nodeid;
2786 req->in.numargs = 1;
2787 req->in.args[0].size = sizeof(inarg);
2788 req->in.args[0].value = &inarg;
2789 fuse_request_send(fc, req);
2790 err = req->out.h.error;
2791 if (err == -ENOSYS) {
2792 fc->no_fallocate = 1;
2795 fuse_put_request(fc, req);
2800 /* we could have extended the file */
2801 if (!(mode & FALLOC_FL_KEEP_SIZE))
2802 fuse_write_update_size(inode, offset + length);
2804 if (mode & FALLOC_FL_PUNCH_HOLE)
2805 truncate_pagecache_range(inode, offset, offset + length - 1);
2807 fuse_invalidate_attr(inode);
2810 if (!(mode & FALLOC_FL_KEEP_SIZE))
2811 clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
2814 mutex_unlock(&inode->i_mutex);
2819 static const struct file_operations fuse_file_operations = {
2820 .llseek = fuse_file_llseek,
2821 .read = do_sync_read,
2822 .aio_read = fuse_file_aio_read,
2823 .write = do_sync_write,
2824 .aio_write = fuse_file_aio_write,
2825 .mmap = fuse_file_mmap,
2827 .flush = fuse_flush,
2828 .release = fuse_release,
2829 .fsync = fuse_fsync,
2830 .lock = fuse_file_lock,
2831 .flock = fuse_file_flock,
2832 .splice_read = generic_file_splice_read,
2833 .unlocked_ioctl = fuse_file_ioctl,
2834 .compat_ioctl = fuse_file_compat_ioctl,
2835 .poll = fuse_file_poll,
2836 .fallocate = fuse_file_fallocate,
2839 static const struct file_operations fuse_direct_io_file_operations = {
2840 .llseek = fuse_file_llseek,
2841 .read = fuse_direct_read,
2842 .write = fuse_direct_write,
2843 .mmap = fuse_direct_mmap,
2845 .flush = fuse_flush,
2846 .release = fuse_release,
2847 .fsync = fuse_fsync,
2848 .lock = fuse_file_lock,
2849 .flock = fuse_file_flock,
2850 .unlocked_ioctl = fuse_file_ioctl,
2851 .compat_ioctl = fuse_file_compat_ioctl,
2852 .poll = fuse_file_poll,
2853 .fallocate = fuse_file_fallocate,
2854 /* no splice_read */
2857 static const struct address_space_operations fuse_file_aops = {
2858 .readpage = fuse_readpage,
2859 .writepage = fuse_writepage,
2860 .writepages = fuse_writepages,
2861 .launder_page = fuse_launder_page,
2862 .readpages = fuse_readpages,
2863 .set_page_dirty = __set_page_dirty_nobuffers,
2865 .direct_IO = fuse_direct_IO,
2868 void fuse_init_file_inode(struct inode *inode)
2870 inode->i_fop = &fuse_file_operations;
2871 inode->i_data.a_ops = &fuse_file_aops;