2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include <linux/pagemap.h>
21 #include <linux/highmem.h>
22 #include <linux/time.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/smp_lock.h>
26 #include <linux/backing-dev.h>
27 #include <linux/mpage.h>
28 #include <linux/swap.h>
29 #include <linux/writeback.h>
30 #include <linux/statfs.h>
31 #include <linux/compat.h>
32 #include <linux/version.h>
35 #include "transaction.h"
36 #include "btrfs_inode.h"
37 #include "ordered-data.h"
39 #include "print-tree.h"
42 static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
43 struct page **prepared_pages,
44 const char __user * buf)
48 int offset = pos & (PAGE_CACHE_SIZE - 1);
50 for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
51 size_t count = min_t(size_t,
52 PAGE_CACHE_SIZE - offset, write_bytes);
53 struct page *page = prepared_pages[i];
54 fault_in_pages_readable(buf, count);
56 /* Copy data from userspace to the current page */
58 page_fault = __copy_from_user(page_address(page) + offset,
60 /* Flush processor's dcache for this page */
61 flush_dcache_page(page);
69 return page_fault ? -EFAULT : 0;
72 static void btrfs_drop_pages(struct page **pages, size_t num_pages)
75 for (i = 0; i < num_pages; i++) {
78 unlock_page(pages[i]);
79 mark_page_accessed(pages[i]);
80 page_cache_release(pages[i]);
84 static int noinline insert_inline_extent(struct btrfs_trans_handle *trans,
85 struct btrfs_root *root, struct inode *inode,
86 u64 offset, size_t size,
87 struct page **pages, size_t page_offset,
91 struct btrfs_path *path;
92 struct extent_buffer *leaf;
95 struct btrfs_file_extent_item *ei;
103 path = btrfs_alloc_path();
107 btrfs_set_trans_block_group(trans, inode);
109 key.objectid = inode->i_ino;
111 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
113 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
119 struct btrfs_key found_key;
121 if (path->slots[0] == 0)
125 leaf = path->nodes[0];
126 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
128 if (found_key.objectid != inode->i_ino)
131 if (found_key.type != BTRFS_EXTENT_DATA_KEY)
133 ei = btrfs_item_ptr(leaf, path->slots[0],
134 struct btrfs_file_extent_item);
136 if (btrfs_file_extent_type(leaf, ei) !=
137 BTRFS_FILE_EXTENT_INLINE) {
140 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
147 leaf = path->nodes[0];
148 ei = btrfs_item_ptr(leaf, path->slots[0],
149 struct btrfs_file_extent_item);
151 if (btrfs_file_extent_type(leaf, ei) !=
152 BTRFS_FILE_EXTENT_INLINE) {
154 btrfs_print_leaf(root, leaf);
155 printk("found wasn't inline offset %Lu inode %lu\n",
156 offset, inode->i_ino);
159 found_size = btrfs_file_extent_inline_len(leaf,
160 btrfs_item_nr(leaf, path->slots[0]));
161 found_end = key.offset + found_size;
163 if (found_end < offset + size) {
164 btrfs_release_path(root, path);
165 ret = btrfs_search_slot(trans, root, &key, path,
166 offset + size - found_end, 1);
169 ret = btrfs_extend_item(trans, root, path,
170 offset + size - found_end);
175 leaf = path->nodes[0];
176 ei = btrfs_item_ptr(leaf, path->slots[0],
177 struct btrfs_file_extent_item);
179 if (found_end < offset) {
180 ptr = btrfs_file_extent_inline_start(ei) + found_size;
181 memset_extent_buffer(leaf, 0, ptr, offset - found_end);
185 btrfs_release_path(root, path);
186 datasize = offset + size - key.offset;
187 datasize = btrfs_file_extent_calc_inline_size(datasize);
188 ret = btrfs_insert_empty_item(trans, root, path, &key,
192 printk("got bad ret %d\n", ret);
195 leaf = path->nodes[0];
196 ei = btrfs_item_ptr(leaf, path->slots[0],
197 struct btrfs_file_extent_item);
198 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
199 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
201 ptr = btrfs_file_extent_inline_start(ei) + offset - key.offset;
207 kaddr = kmap_atomic(page, KM_USER0);
208 cur_size = min_t(size_t, PAGE_CACHE_SIZE - page_offset, size);
209 write_extent_buffer(leaf, kaddr + page_offset, ptr, cur_size);
210 kunmap_atomic(kaddr, KM_USER0);
214 if (i >= num_pages) {
215 printk("i %d num_pages %d\n", i, num_pages);
219 btrfs_mark_buffer_dirty(leaf);
221 btrfs_free_path(path);
225 static int noinline dirty_and_release_pages(struct btrfs_trans_handle *trans,
226 struct btrfs_root *root,
235 struct inode *inode = fdentry(file)->d_inode;
236 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
240 u64 end_of_last_block;
241 u64 end_pos = pos + write_bytes;
243 loff_t isize = i_size_read(inode);
245 start_pos = pos & ~((u64)root->sectorsize - 1);
246 num_bytes = (write_bytes + pos - start_pos +
247 root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
249 end_of_last_block = start_pos + num_bytes - 1;
251 lock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
252 mutex_lock(&root->fs_info->fs_mutex);
253 trans = btrfs_start_transaction(root, 1);
258 btrfs_set_trans_block_group(trans, inode);
259 inode->i_blocks += num_bytes >> 9;
262 if ((end_of_last_block & 4095) == 0) {
263 printk("strange end of last %Lu %zu %Lu\n", start_pos, write_bytes, end_of_last_block);
265 set_extent_uptodate(io_tree, start_pos, end_of_last_block, GFP_NOFS);
267 /* FIXME...EIEIO, ENOSPC and more */
269 /* insert any holes we need to create */
270 if (inode->i_size < start_pos) {
271 u64 last_pos_in_file;
273 u64 mask = root->sectorsize - 1;
274 last_pos_in_file = (isize + mask) & ~mask;
275 hole_size = (end_pos - last_pos_in_file + mask) & ~mask;
277 if (last_pos_in_file < start_pos) {
278 err = btrfs_drop_extents(trans, root, inode,
280 last_pos_in_file + hole_size,
286 err = btrfs_insert_file_extent(trans, root,
290 btrfs_drop_extent_cache(inode, last_pos_in_file,
291 last_pos_in_file + hole_size -1);
292 btrfs_check_file(root, inode);
299 * either allocate an extent for the new bytes or setup the key
300 * to show we are doing inline data in the extent
302 inline_size = end_pos;
303 if (isize >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
304 inline_size > root->fs_info->max_inline ||
305 (inline_size & (root->sectorsize -1)) == 0 ||
306 inline_size >= BTRFS_MAX_INLINE_DATA_SIZE(root)) {
308 u64 existing_delalloc = 0;
310 for (i = 0; i < num_pages; i++) {
311 struct page *p = pages[i];
315 last_end = (u64)(pages[num_pages -1]->index) <<
317 last_end += PAGE_CACHE_SIZE - 1;
318 if (start_pos < isize) {
319 u64 delalloc_start = start_pos;
320 existing_delalloc = count_range_bits(io_tree,
322 end_of_last_block, (u64)-1,
325 set_extent_delalloc(io_tree, start_pos, end_of_last_block,
327 btrfs_add_ordered_inode(inode);
330 /* step one, delete the existing extents in this range */
331 aligned_end = (pos + write_bytes + root->sectorsize - 1) &
332 ~((u64)root->sectorsize - 1);
333 err = btrfs_drop_extents(trans, root, inode, start_pos,
334 aligned_end, aligned_end, &hint_byte);
337 if (isize > inline_size)
338 inline_size = min_t(u64, isize, aligned_end);
339 inline_size -= start_pos;
340 err = insert_inline_extent(trans, root, inode, start_pos,
341 inline_size, pages, 0, num_pages);
342 btrfs_drop_extent_cache(inode, start_pos, aligned_end - 1);
345 if (end_pos > isize) {
346 i_size_write(inode, end_pos);
347 btrfs_update_inode(trans, root, inode);
350 err = btrfs_end_transaction(trans, root);
352 mutex_unlock(&root->fs_info->fs_mutex);
353 unlock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
357 int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
359 struct extent_map *em;
360 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
363 spin_lock(&em_tree->lock);
364 em = lookup_extent_mapping(em_tree, start, end);
366 spin_unlock(&em_tree->lock);
369 remove_extent_mapping(em_tree, em);
370 spin_unlock(&em_tree->lock);
374 /* once for the tree*/
380 int btrfs_check_file(struct btrfs_root *root, struct inode *inode)
384 struct btrfs_path *path;
385 struct btrfs_key found_key;
386 struct extent_buffer *leaf;
387 struct btrfs_file_extent_item *extent;
396 path = btrfs_alloc_path();
397 ret = btrfs_lookup_file_extent(NULL, root, path, inode->i_ino,
400 nritems = btrfs_header_nritems(path->nodes[0]);
401 if (path->slots[0] >= nritems) {
402 ret = btrfs_next_leaf(root, path);
405 nritems = btrfs_header_nritems(path->nodes[0]);
407 slot = path->slots[0];
408 leaf = path->nodes[0];
409 btrfs_item_key_to_cpu(leaf, &found_key, slot);
410 if (found_key.objectid != inode->i_ino)
412 if (found_key.type != BTRFS_EXTENT_DATA_KEY)
415 if (found_key.offset != last_offset) {
417 btrfs_print_leaf(root, leaf);
418 printk("inode %lu found offset %Lu expected %Lu\n",
419 inode->i_ino, found_key.offset, last_offset);
423 extent = btrfs_item_ptr(leaf, slot,
424 struct btrfs_file_extent_item);
425 found_type = btrfs_file_extent_type(leaf, extent);
426 if (found_type == BTRFS_FILE_EXTENT_REG) {
427 extent_end = found_key.offset +
428 btrfs_file_extent_num_bytes(leaf, extent);
429 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
430 struct btrfs_item *item;
431 item = btrfs_item_nr(leaf, slot);
432 extent_end = found_key.offset +
433 btrfs_file_extent_inline_len(leaf, item);
434 extent_end = (extent_end + root->sectorsize - 1) &
435 ~((u64)root->sectorsize -1 );
437 last_offset = extent_end;
440 if (last_offset < inode->i_size) {
442 btrfs_print_leaf(root, leaf);
443 printk("inode %lu found offset %Lu size %Lu\n", inode->i_ino,
444 last_offset, inode->i_size);
449 btrfs_free_path(path);
455 * this is very complex, but the basic idea is to drop all extents
456 * in the range start - end. hint_block is filled in with a block number
457 * that would be a good hint to the block allocator for this file.
459 * If an extent intersects the range but is not entirely inside the range
460 * it is either truncated or split. Anything entirely inside the range
461 * is deleted from the tree.
463 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
464 struct btrfs_root *root, struct inode *inode,
465 u64 start, u64 end, u64 inline_limit, u64 *hint_byte)
468 u64 search_start = start;
469 struct extent_buffer *leaf;
470 struct btrfs_file_extent_item *extent;
471 struct btrfs_path *path;
472 struct btrfs_key key;
473 struct btrfs_file_extent_item old;
483 btrfs_drop_extent_cache(inode, start, end - 1);
485 path = btrfs_alloc_path();
490 btrfs_release_path(root, path);
491 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
496 if (path->slots[0] == 0) {
508 leaf = path->nodes[0];
509 slot = path->slots[0];
511 btrfs_item_key_to_cpu(leaf, &key, slot);
513 if (key.offset >= end || key.objectid != inode->i_ino) {
516 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY) {
520 search_start = key.offset;
523 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
524 extent = btrfs_item_ptr(leaf, slot,
525 struct btrfs_file_extent_item);
526 found_type = btrfs_file_extent_type(leaf, extent);
527 if (found_type == BTRFS_FILE_EXTENT_REG) {
529 btrfs_file_extent_disk_bytenr(leaf,
532 *hint_byte = extent_end;
534 extent_end = key.offset +
535 btrfs_file_extent_num_bytes(leaf, extent);
537 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
538 struct btrfs_item *item;
539 item = btrfs_item_nr(leaf, slot);
541 extent_end = key.offset +
542 btrfs_file_extent_inline_len(leaf, item);
545 extent_end = search_start;
548 /* we found nothing we can drop */
549 if ((!found_extent && !found_inline) ||
550 search_start >= extent_end) {
553 nritems = btrfs_header_nritems(leaf);
554 if (slot >= nritems - 1) {
555 nextret = btrfs_next_leaf(root, path);
566 u64 mask = root->sectorsize - 1;
567 search_start = (extent_end + mask) & ~mask;
569 search_start = extent_end;
570 if (end <= extent_end && start >= key.offset && found_inline) {
571 *hint_byte = EXTENT_MAP_INLINE;
574 if (end < extent_end && end >= key.offset) {
577 btrfs_file_extent_disk_bytenr(leaf, extent);
579 btrfs_file_extent_disk_num_bytes(leaf,
581 read_extent_buffer(leaf, &old,
582 (unsigned long)extent,
584 if (disk_bytenr != 0) {
585 ret = btrfs_inc_extent_ref(trans, root,
586 disk_bytenr, disk_num_bytes,
587 root->root_key.objectid,
594 if (found_inline && start <= key.offset &&
595 inline_limit < extent_end)
598 /* truncate existing extent */
599 if (start > key.offset) {
603 WARN_ON(start & (root->sectorsize - 1));
605 new_num = start - key.offset;
606 old_num = btrfs_file_extent_num_bytes(leaf,
609 btrfs_file_extent_disk_bytenr(leaf,
611 if (btrfs_file_extent_disk_bytenr(leaf,
614 (old_num - new_num) >> 9;
616 btrfs_set_file_extent_num_bytes(leaf, extent,
618 btrfs_mark_buffer_dirty(leaf);
619 } else if (key.offset < inline_limit &&
620 (end > extent_end) &&
621 (inline_limit < extent_end)) {
623 new_size = btrfs_file_extent_calc_inline_size(
624 inline_limit - key.offset);
625 btrfs_truncate_item(trans, root, path,
629 /* delete the entire extent */
632 u64 disk_num_bytes = 0;
633 u64 extent_num_bytes = 0;
637 root_gen = btrfs_header_generation(leaf);
638 root_owner = btrfs_header_owner(leaf);
641 btrfs_file_extent_disk_bytenr(leaf,
644 btrfs_file_extent_disk_num_bytes(leaf,
647 btrfs_file_extent_num_bytes(leaf, extent);
649 btrfs_file_extent_disk_bytenr(leaf,
652 ret = btrfs_del_item(trans, root, path);
653 /* TODO update progress marker and return */
655 btrfs_release_path(root, path);
657 if (found_extent && disk_bytenr != 0) {
658 inode->i_blocks -= extent_num_bytes >> 9;
659 ret = btrfs_free_extent(trans, root,
663 root_gen, inode->i_ino,
668 if (!bookend && search_start >= end) {
675 if (bookend && found_inline && start <= key.offset &&
676 inline_limit < extent_end && key.offset <= inline_limit) {
678 new_size = btrfs_file_extent_calc_inline_size(
679 extent_end - inline_limit);
680 btrfs_truncate_item(trans, root, path, new_size, 0);
682 /* create bookend, splitting the extent in two */
683 if (bookend && found_extent) {
684 struct btrfs_key ins;
685 ins.objectid = inode->i_ino;
687 btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
688 btrfs_release_path(root, path);
689 ret = btrfs_insert_empty_item(trans, root, path, &ins,
692 leaf = path->nodes[0];
694 btrfs_print_leaf(root, leaf);
695 printk("got %d on inserting %Lu %u %Lu start %Lu end %Lu found %Lu %Lu keep was %d\n", ret , ins.objectid, ins.type, ins.offset, start, end, key.offset, extent_end, keep);
698 extent = btrfs_item_ptr(leaf, path->slots[0],
699 struct btrfs_file_extent_item);
700 write_extent_buffer(leaf, &old,
701 (unsigned long)extent, sizeof(old));
703 btrfs_set_file_extent_offset(leaf, extent,
704 le64_to_cpu(old.offset) + end - key.offset);
705 WARN_ON(le64_to_cpu(old.num_bytes) <
707 btrfs_set_file_extent_num_bytes(leaf, extent,
709 btrfs_set_file_extent_type(leaf, extent,
710 BTRFS_FILE_EXTENT_REG);
712 btrfs_mark_buffer_dirty(path->nodes[0]);
713 if (le64_to_cpu(old.disk_bytenr) != 0) {
715 btrfs_file_extent_num_bytes(leaf,
723 btrfs_free_path(path);
728 * this gets pages into the page cache and locks them down
730 static int prepare_pages(struct btrfs_root *root, struct file *file,
731 struct page **pages, size_t num_pages,
732 loff_t pos, unsigned long first_index,
733 unsigned long last_index, size_t write_bytes)
736 unsigned long index = pos >> PAGE_CACHE_SHIFT;
737 struct inode *inode = fdentry(file)->d_inode;
741 start_pos = pos & ~((u64)root->sectorsize - 1);
743 memset(pages, 0, num_pages * sizeof(struct page *));
745 for (i = 0; i < num_pages; i++) {
746 pages[i] = grab_cache_page(inode->i_mapping, index + i);
751 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
752 ClearPageDirty(pages[i]);
754 cancel_dirty_page(pages[i], PAGE_CACHE_SIZE);
756 wait_on_page_writeback(pages[i]);
757 set_page_extent_mapped(pages[i]);
758 WARN_ON(!PageLocked(pages[i]));
763 static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
764 size_t count, loff_t *ppos)
768 ssize_t num_written = 0;
771 struct inode *inode = fdentry(file)->d_inode;
772 struct btrfs_root *root = BTRFS_I(inode)->root;
773 struct page **pages = NULL;
775 struct page *pinned[2];
776 unsigned long first_index;
777 unsigned long last_index;
779 nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE,
780 PAGE_CACHE_SIZE / (sizeof(struct page *)));
783 if (file->f_flags & O_DIRECT)
789 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
790 current->backing_dev_info = inode->i_mapping->backing_dev_info;
791 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
796 err = remove_suid(fdentry(file));
799 file_update_time(file);
801 pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
803 mutex_lock(&inode->i_mutex);
804 first_index = pos >> PAGE_CACHE_SHIFT;
805 last_index = (pos + count) >> PAGE_CACHE_SHIFT;
808 * there are lots of better ways to do this, but this code
809 * makes sure the first and last page in the file range are
810 * up to date and ready for cow
812 if ((pos & (PAGE_CACHE_SIZE - 1))) {
813 pinned[0] = grab_cache_page(inode->i_mapping, first_index);
814 if (!PageUptodate(pinned[0])) {
815 ret = btrfs_readpage(NULL, pinned[0]);
817 wait_on_page_locked(pinned[0]);
819 unlock_page(pinned[0]);
822 if ((pos + count) & (PAGE_CACHE_SIZE - 1)) {
823 pinned[1] = grab_cache_page(inode->i_mapping, last_index);
824 if (!PageUptodate(pinned[1])) {
825 ret = btrfs_readpage(NULL, pinned[1]);
827 wait_on_page_locked(pinned[1]);
829 unlock_page(pinned[1]);
834 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
835 size_t write_bytes = min(count, nrptrs *
836 (size_t)PAGE_CACHE_SIZE -
838 size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
841 WARN_ON(num_pages > nrptrs);
842 memset(pages, 0, sizeof(pages));
844 mutex_lock(&root->fs_info->fs_mutex);
845 ret = btrfs_check_free_space(root, write_bytes, 0);
846 mutex_unlock(&root->fs_info->fs_mutex);
850 ret = prepare_pages(root, file, pages, num_pages,
851 pos, first_index, last_index,
856 ret = btrfs_copy_from_user(pos, num_pages,
857 write_bytes, pages, buf);
859 btrfs_drop_pages(pages, num_pages);
863 ret = dirty_and_release_pages(NULL, root, file, pages,
864 num_pages, pos, write_bytes);
865 btrfs_drop_pages(pages, num_pages);
870 count -= write_bytes;
872 num_written += write_bytes;
874 balance_dirty_pages_ratelimited_nr(inode->i_mapping, num_pages);
875 if (num_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1)
876 btrfs_btree_balance_dirty(root, 1);
877 btrfs_throttle(root);
881 mutex_unlock(&inode->i_mutex);
886 page_cache_release(pinned[0]);
888 page_cache_release(pinned[1]);
891 if (num_written > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
892 err = sync_page_range(inode, inode->i_mapping,
893 start_pos, num_written);
897 current->backing_dev_info = NULL;
898 return num_written ? num_written : err;
901 static int btrfs_sync_file(struct file *file,
902 struct dentry *dentry, int datasync)
904 struct inode *inode = dentry->d_inode;
905 struct btrfs_root *root = BTRFS_I(inode)->root;
907 struct btrfs_trans_handle *trans;
910 * check the transaction that last modified this inode
911 * and see if its already been committed
913 mutex_lock(&root->fs_info->fs_mutex);
914 if (!BTRFS_I(inode)->last_trans)
916 mutex_lock(&root->fs_info->trans_mutex);
917 if (BTRFS_I(inode)->last_trans <=
918 root->fs_info->last_trans_committed) {
919 BTRFS_I(inode)->last_trans = 0;
920 mutex_unlock(&root->fs_info->trans_mutex);
923 mutex_unlock(&root->fs_info->trans_mutex);
926 * ok we haven't committed the transaction yet, lets do a commit
928 trans = btrfs_start_transaction(root, 1);
933 ret = btrfs_commit_transaction(trans, root);
935 mutex_unlock(&root->fs_info->fs_mutex);
936 return ret > 0 ? EIO : ret;
939 static struct vm_operations_struct btrfs_file_vm_ops = {
940 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
941 .nopage = filemap_nopage,
942 .populate = filemap_populate,
944 .fault = filemap_fault,
946 .page_mkwrite = btrfs_page_mkwrite,
949 static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
951 vma->vm_ops = &btrfs_file_vm_ops;
956 struct file_operations btrfs_file_operations = {
957 .llseek = generic_file_llseek,
958 .read = do_sync_read,
959 .aio_read = generic_file_aio_read,
960 .splice_read = generic_file_splice_read,
961 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
962 .sendfile = generic_file_sendfile,
964 .write = btrfs_file_write,
965 .mmap = btrfs_file_mmap,
966 .open = generic_file_open,
967 .fsync = btrfs_sync_file,
968 .unlocked_ioctl = btrfs_ioctl,
970 .compat_ioctl = btrfs_ioctl,