diff options
Diffstat (limited to 'fs/fuse/file.c')
-rw-r--r-- | fs/fuse/file.c | 120 |
1 files changed, 92 insertions, 28 deletions
diff --git a/fs/fuse/file.c b/fs/fuse/file.c index bac51c32d660..e573b0cd2737 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -357,7 +357,7 @@ u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id) struct fuse_writepage_args { struct fuse_io_args ia; - struct list_head writepages_entry; + struct rb_node writepages_entry; struct list_head queue_entry; struct fuse_writepage_args *next; struct inode *inode; @@ -366,17 +366,23 @@ struct fuse_writepage_args { static struct fuse_writepage_args *fuse_find_writeback(struct fuse_inode *fi, pgoff_t idx_from, pgoff_t idx_to) { - struct fuse_writepage_args *wpa; + struct rb_node *n; + + n = fi->writepages.rb_node; - list_for_each_entry(wpa, &fi->writepages, writepages_entry) { + while (n) { + struct fuse_writepage_args *wpa; pgoff_t curr_index; + wpa = rb_entry(n, struct fuse_writepage_args, writepages_entry); WARN_ON(get_fuse_inode(wpa->inode) != fi); curr_index = wpa->ia.write.in.offset >> PAGE_SHIFT; - if (idx_from < curr_index + wpa->ia.ap.num_pages && - curr_index <= idx_to) { + if (idx_from >= curr_index + wpa->ia.ap.num_pages) + n = n->rb_right; + else if (idx_to < curr_index) + n = n->rb_left; + else return wpa; - } } return NULL; } @@ -445,9 +451,6 @@ static int fuse_flush(struct file *file, fl_owner_t id) if (is_bad_inode(inode)) return -EIO; - if (fc->no_flush) - return 0; - err = write_inode_now(inode, 1); if (err) return err; @@ -460,6 +463,10 @@ static int fuse_flush(struct file *file, fl_owner_t id) if (err) return err; + err = 0; + if (fc->no_flush) + goto inval_attr_out; + memset(&inarg, 0, sizeof(inarg)); inarg.fh = ff->fh; inarg.lock_owner = fuse_lock_owner_id(fc, id); @@ -475,6 +482,14 @@ static int fuse_flush(struct file *file, fl_owner_t id) fc->no_flush = 1; err = 0; } + +inval_attr_out: + /* + * In memory i_blocks is not maintained by fuse, if writeback cache is + * enabled, i_blocks from cached attr may not be accurate. + */ + if (!err && fc->writeback_cache) + fuse_invalidate_attr(inode); return err; } @@ -712,6 +727,7 @@ static ssize_t fuse_async_req_send(struct fuse_conn *fc, spin_unlock(&io->lock); ia->ap.args.end = fuse_aio_complete_req; + ia->ap.args.may_block = io->should_dirty; err = fuse_simple_background(fc, &ia->ap.args, GFP_KERNEL); if (err) fuse_aio_complete_req(fc, &ia->ap.args, err); @@ -1570,7 +1586,7 @@ static void fuse_writepage_finish(struct fuse_conn *fc, struct backing_dev_info *bdi = inode_to_bdi(inode); int i; - list_del(&wpa->writepages_entry); + rb_erase(&wpa->writepages_entry, &fi->writepages); for (i = 0; i < ap->num_pages; i++) { dec_wb_stat(&bdi->wb, WB_WRITEBACK); dec_node_page_state(ap->pages[i], NR_WRITEBACK_TEMP); @@ -1658,6 +1674,36 @@ __acquires(fi->lock) } } +static void tree_insert(struct rb_root *root, struct fuse_writepage_args *wpa) +{ + pgoff_t idx_from = wpa->ia.write.in.offset >> PAGE_SHIFT; + pgoff_t idx_to = idx_from + wpa->ia.ap.num_pages - 1; + struct rb_node **p = &root->rb_node; + struct rb_node *parent = NULL; + + WARN_ON(!wpa->ia.ap.num_pages); + while (*p) { + struct fuse_writepage_args *curr; + pgoff_t curr_index; + + parent = *p; + curr = rb_entry(parent, struct fuse_writepage_args, + writepages_entry); + WARN_ON(curr->inode != wpa->inode); + curr_index = curr->ia.write.in.offset >> PAGE_SHIFT; + + if (idx_from >= curr_index + curr->ia.ap.num_pages) + p = &(*p)->rb_right; + else if (idx_to < curr_index) + p = &(*p)->rb_left; + else + return (void) WARN_ON(true); + } + + rb_link_node(&wpa->writepages_entry, parent, p); + rb_insert_color(&wpa->writepages_entry, root); +} + static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_args *args, int error) { @@ -1676,7 +1722,7 @@ static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_args *args, wpa->next = next->next; next->next = NULL; next->ia.ff = fuse_file_get(wpa->ia.ff); - list_add(&next->writepages_entry, &fi->writepages); + tree_insert(&fi->writepages, next); /* * Skip fuse_flush_writepages() to make it easy to crop requests @@ -1811,7 +1857,7 @@ static int fuse_writepage_locked(struct page *page) inc_node_page_state(tmp_page, NR_WRITEBACK_TEMP); spin_lock(&fi->lock); - list_add(&wpa->writepages_entry, &fi->writepages); + tree_insert(&fi->writepages, wpa); list_add_tail(&wpa->queue_entry, &fi->queued_writes); fuse_flush_writepages(inode); spin_unlock(&fi->lock); @@ -1923,10 +1969,10 @@ static bool fuse_writepage_in_flight(struct fuse_writepage_args *new_wpa, WARN_ON(new_ap->num_pages != 0); spin_lock(&fi->lock); - list_del(&new_wpa->writepages_entry); + rb_erase(&new_wpa->writepages_entry, &fi->writepages); old_wpa = fuse_find_writeback(fi, page->index, page->index); if (!old_wpa) { - list_add(&new_wpa->writepages_entry, &fi->writepages); + tree_insert(&fi->writepages, new_wpa); spin_unlock(&fi->lock); return false; } @@ -2041,7 +2087,7 @@ static int fuse_writepages_fill(struct page *page, wpa->inode = inode; spin_lock(&fi->lock); - list_add(&wpa->writepages_entry, &fi->writepages); + tree_insert(&fi->writepages, wpa); spin_unlock(&fi->lock); data->wpa = wpa; @@ -3235,13 +3281,11 @@ static ssize_t __fuse_copy_file_range(struct file *file_in, loff_t pos_in, if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) return -EXDEV; - if (fc->writeback_cache) { - inode_lock(inode_in); - err = fuse_writeback_range(inode_in, pos_in, pos_in + len); - inode_unlock(inode_in); - if (err) - return err; - } + inode_lock(inode_in); + err = fuse_writeback_range(inode_in, pos_in, pos_in + len - 1); + inode_unlock(inode_in); + if (err) + return err; inode_lock(inode_out); @@ -3249,11 +3293,27 @@ static ssize_t __fuse_copy_file_range(struct file *file_in, loff_t pos_in, if (err) goto out; - if (fc->writeback_cache) { - err = fuse_writeback_range(inode_out, pos_out, pos_out + len); - if (err) - goto out; - } + /* + * Write out dirty pages in the destination file before sending the COPY + * request to userspace. After the request is completed, truncate off + * pages (including partial ones) from the cache that have been copied, + * since these contain stale data at that point. + * + * This should be mostly correct, but if the COPY writes to partial + * pages (at the start or end) and the parts not covered by the COPY are + * written through a memory map after calling fuse_writeback_range(), + * then these partial page modifications will be lost on truncation. + * + * It is unlikely that someone would rely on such mixed style + * modifications. Yet this does give less guarantees than if the + * copying was performed with write(2). + * + * To fix this a i_mmap_sem style lock could be used to prevent new + * faults while the copy is ongoing. + */ + err = fuse_writeback_range(inode_out, pos_out, pos_out + len - 1); + if (err) + goto out; if (is_unstable) set_bit(FUSE_I_SIZE_UNSTABLE, &fi_out->state); @@ -3274,6 +3334,10 @@ static ssize_t __fuse_copy_file_range(struct file *file_in, loff_t pos_in, if (err) goto out; + truncate_inode_pages_range(inode_out->i_mapping, + ALIGN_DOWN(pos_out, PAGE_SIZE), + ALIGN(pos_out + outarg.size, PAGE_SIZE) - 1); + if (fc->writeback_cache) { fuse_write_update_size(inode_out, pos_out + outarg.size); file_update_time(file_out); @@ -3351,5 +3415,5 @@ void fuse_init_file_inode(struct inode *inode) INIT_LIST_HEAD(&fi->queued_writes); fi->writectr = 0; init_waitqueue_head(&fi->page_waitq); - INIT_LIST_HEAD(&fi->writepages); + fi->writepages = RB_ROOT; } |