737 lines
19 KiB
C
737 lines
19 KiB
C
/*
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* Copyright (C) 2007 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include <linux/buffer_head.h>
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#include <linux/fs.h>
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#include <linux/pagemap.h>
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#include <linux/highmem.h>
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#include <linux/time.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/smp_lock.h>
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#include <linux/backing-dev.h>
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#include <linux/mpage.h>
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#include <linux/swap.h>
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#include <linux/writeback.h>
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#include <linux/statfs.h>
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#include <linux/compat.h>
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#include <linux/version.h>
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#include "ctree.h"
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#include "disk-io.h"
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#include "transaction.h"
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#include "btrfs_inode.h"
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#include "ioctl.h"
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#include "print-tree.h"
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static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
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struct page **prepared_pages,
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const char __user * buf)
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{
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long page_fault = 0;
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int i;
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int offset = pos & (PAGE_CACHE_SIZE - 1);
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for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
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size_t count = min_t(size_t,
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PAGE_CACHE_SIZE - offset, write_bytes);
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struct page *page = prepared_pages[i];
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fault_in_pages_readable(buf, count);
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/* Copy data from userspace to the current page */
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kmap(page);
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page_fault = __copy_from_user(page_address(page) + offset,
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buf, count);
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/* Flush processor's dcache for this page */
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flush_dcache_page(page);
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kunmap(page);
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buf += count;
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write_bytes -= count;
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if (page_fault)
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break;
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}
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return page_fault ? -EFAULT : 0;
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}
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static void btrfs_drop_pages(struct page **pages, size_t num_pages)
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{
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size_t i;
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for (i = 0; i < num_pages; i++) {
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if (!pages[i])
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break;
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unlock_page(pages[i]);
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mark_page_accessed(pages[i]);
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page_cache_release(pages[i]);
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}
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}
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static int insert_inline_extent(struct btrfs_trans_handle *trans,
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struct btrfs_root *root, struct inode *inode,
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u64 offset, ssize_t size,
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struct page *page, size_t page_offset)
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{
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struct btrfs_key key;
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struct btrfs_path *path;
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char *ptr, *kaddr;
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struct btrfs_file_extent_item *ei;
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u32 datasize;
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int err = 0;
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int ret;
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path = btrfs_alloc_path();
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if (!path)
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return -ENOMEM;
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btrfs_set_trans_block_group(trans, inode);
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key.objectid = inode->i_ino;
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key.offset = offset;
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key.flags = 0;
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btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
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BUG_ON(size >= PAGE_CACHE_SIZE);
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datasize = btrfs_file_extent_calc_inline_size(size);
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ret = btrfs_insert_empty_item(trans, root, path, &key,
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datasize);
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if (ret) {
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err = ret;
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goto fail;
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}
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ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
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path->slots[0], struct btrfs_file_extent_item);
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btrfs_set_file_extent_generation(ei, trans->transid);
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btrfs_set_file_extent_type(ei,
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BTRFS_FILE_EXTENT_INLINE);
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ptr = btrfs_file_extent_inline_start(ei);
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kaddr = kmap_atomic(page, KM_USER0);
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btrfs_memcpy(root, path->nodes[0]->b_data,
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ptr, kaddr + page_offset, size);
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kunmap_atomic(kaddr, KM_USER0);
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btrfs_mark_buffer_dirty(path->nodes[0]);
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fail:
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btrfs_free_path(path);
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return err;
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}
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static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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struct file *file,
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struct page **pages,
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size_t num_pages,
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loff_t pos,
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size_t write_bytes)
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{
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int err = 0;
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int i;
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struct inode *inode = file->f_path.dentry->d_inode;
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struct extent_map *em;
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struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
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u64 hint_block;
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u64 num_blocks;
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u64 start_pos;
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u64 end_of_last_block;
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u64 end_pos = pos + write_bytes;
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loff_t isize = i_size_read(inode);
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em = alloc_extent_map(GFP_NOFS);
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if (!em)
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return -ENOMEM;
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em->bdev = inode->i_sb->s_bdev;
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start_pos = pos & ~((u64)root->blocksize - 1);
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num_blocks = (write_bytes + pos - start_pos + root->blocksize - 1) >>
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inode->i_blkbits;
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down_read(&BTRFS_I(inode)->root->snap_sem);
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end_of_last_block = start_pos + (num_blocks << inode->i_blkbits) - 1;
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lock_extent(em_tree, start_pos, end_of_last_block, GFP_NOFS);
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mutex_lock(&root->fs_info->fs_mutex);
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trans = btrfs_start_transaction(root, 1);
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if (!trans) {
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err = -ENOMEM;
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goto out_unlock;
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}
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btrfs_set_trans_block_group(trans, inode);
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inode->i_blocks += num_blocks << 3;
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hint_block = 0;
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if ((end_of_last_block & 4095) == 0) {
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printk("strange end of last %Lu %zu %Lu\n", start_pos, write_bytes, end_of_last_block);
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}
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set_extent_uptodate(em_tree, start_pos, end_of_last_block, GFP_NOFS);
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/* FIXME...EIEIO, ENOSPC and more */
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/* insert any holes we need to create */
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if (inode->i_size < start_pos) {
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u64 last_pos_in_file;
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u64 hole_size;
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u64 mask = root->blocksize - 1;
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last_pos_in_file = (isize + mask) & ~mask;
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hole_size = (start_pos - last_pos_in_file + mask) & ~mask;
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if (last_pos_in_file < start_pos) {
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err = btrfs_drop_extents(trans, root, inode,
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last_pos_in_file,
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last_pos_in_file + hole_size,
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&hint_block);
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if (err)
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goto failed;
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hole_size >>= inode->i_blkbits;
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err = btrfs_insert_file_extent(trans, root,
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inode->i_ino,
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last_pos_in_file,
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0, 0, hole_size);
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}
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if (err)
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goto failed;
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}
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/*
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* either allocate an extent for the new bytes or setup the key
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* to show we are doing inline data in the extent
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*/
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if (isize >= PAGE_CACHE_SIZE || pos + write_bytes < inode->i_size ||
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pos + write_bytes - start_pos > BTRFS_MAX_INLINE_DATA_SIZE(root)) {
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u64 last_end;
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for (i = 0; i < num_pages; i++) {
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struct page *p = pages[i];
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SetPageUptodate(p);
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set_page_dirty(p);
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}
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last_end = pages[num_pages -1]->index << PAGE_CACHE_SHIFT;
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last_end += PAGE_CACHE_SIZE - 1;
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set_extent_delalloc(em_tree, start_pos, end_of_last_block,
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GFP_NOFS);
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} else {
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struct page *p = pages[0];
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/* step one, delete the existing extents in this range */
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/* FIXME blocksize != pagesize */
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err = btrfs_drop_extents(trans, root, inode, start_pos,
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(pos + write_bytes + root->blocksize -1) &
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~((u64)root->blocksize - 1), &hint_block);
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if (err)
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goto failed;
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err = insert_inline_extent(trans, root, inode, start_pos,
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end_pos - start_pos, p, 0);
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BUG_ON(err);
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em->start = start_pos;
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em->end = end_pos - 1;
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em->block_start = EXTENT_MAP_INLINE;
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em->block_end = EXTENT_MAP_INLINE;
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add_extent_mapping(em_tree, em);
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}
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if (end_pos > isize) {
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i_size_write(inode, end_pos);
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btrfs_update_inode(trans, root, inode);
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}
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failed:
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err = btrfs_end_transaction(trans, root);
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out_unlock:
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mutex_unlock(&root->fs_info->fs_mutex);
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unlock_extent(em_tree, start_pos, end_of_last_block, GFP_NOFS);
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free_extent_map(em);
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up_read(&BTRFS_I(inode)->root->snap_sem);
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return err;
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}
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int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
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{
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struct extent_map *em;
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struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
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while(1) {
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em = lookup_extent_mapping(em_tree, start, end);
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if (!em)
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break;
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remove_extent_mapping(em_tree, em);
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/* once for us */
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free_extent_map(em);
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/* once for the tree*/
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free_extent_map(em);
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}
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return 0;
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}
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/*
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* this is very complex, but the basic idea is to drop all extents
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* in the range start - end. hint_block is filled in with a block number
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* that would be a good hint to the block allocator for this file.
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*
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* If an extent intersects the range but is not entirely inside the range
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* it is either truncated or split. Anything entirely inside the range
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* is deleted from the tree.
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*/
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int btrfs_drop_extents(struct btrfs_trans_handle *trans,
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struct btrfs_root *root, struct inode *inode,
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u64 start, u64 end, u64 *hint_block)
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{
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int ret;
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struct btrfs_key key;
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struct btrfs_leaf *leaf;
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int slot;
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struct btrfs_file_extent_item *extent;
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u64 extent_end = 0;
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int keep;
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struct btrfs_file_extent_item old;
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struct btrfs_path *path;
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u64 search_start = start;
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int bookend;
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int found_type;
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int found_extent;
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int found_inline;
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int recow;
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btrfs_drop_extent_cache(inode, start, end - 1);
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path = btrfs_alloc_path();
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if (!path)
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return -ENOMEM;
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while(1) {
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recow = 0;
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btrfs_release_path(root, path);
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ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
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search_start, -1);
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if (ret < 0)
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goto out;
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if (ret > 0) {
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if (path->slots[0] == 0) {
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ret = 0;
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goto out;
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}
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path->slots[0]--;
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}
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next_slot:
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keep = 0;
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bookend = 0;
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found_extent = 0;
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found_inline = 0;
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extent = NULL;
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leaf = btrfs_buffer_leaf(path->nodes[0]);
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slot = path->slots[0];
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ret = 0;
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btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
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if (key.offset >= end || key.objectid != inode->i_ino) {
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goto out;
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}
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if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY) {
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goto out;
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}
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if (recow) {
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search_start = key.offset;
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continue;
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}
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if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
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extent = btrfs_item_ptr(leaf, slot,
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struct btrfs_file_extent_item);
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found_type = btrfs_file_extent_type(extent);
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if (found_type == BTRFS_FILE_EXTENT_REG) {
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extent_end = key.offset +
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(btrfs_file_extent_num_blocks(extent) <<
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inode->i_blkbits);
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found_extent = 1;
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} else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
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found_inline = 1;
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extent_end = key.offset +
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btrfs_file_extent_inline_len(leaf->items +
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slot);
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}
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} else {
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extent_end = search_start;
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}
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/* we found nothing we can drop */
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if ((!found_extent && !found_inline) ||
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search_start >= extent_end) {
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int nextret;
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u32 nritems;
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nritems = btrfs_header_nritems(
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btrfs_buffer_header(path->nodes[0]));
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if (slot >= nritems - 1) {
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nextret = btrfs_next_leaf(root, path);
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if (nextret)
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goto out;
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recow = 1;
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} else {
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path->slots[0]++;
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}
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goto next_slot;
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}
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/* FIXME, there's only one inline extent allowed right now */
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if (found_inline) {
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u64 mask = root->blocksize - 1;
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search_start = (extent_end + mask) & ~mask;
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} else
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search_start = extent_end;
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if (end < extent_end && end >= key.offset) {
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if (found_extent) {
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u64 disk_blocknr =
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btrfs_file_extent_disk_blocknr(extent);
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u64 disk_num_blocks =
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btrfs_file_extent_disk_num_blocks(extent);
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memcpy(&old, extent, sizeof(old));
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if (disk_blocknr != 0) {
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ret = btrfs_inc_extent_ref(trans, root,
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disk_blocknr, disk_num_blocks);
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BUG_ON(ret);
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}
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}
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WARN_ON(found_inline);
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bookend = 1;
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}
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/* truncate existing extent */
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if (start > key.offset) {
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u64 new_num;
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u64 old_num;
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keep = 1;
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WARN_ON(start & (root->blocksize - 1));
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if (found_extent) {
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new_num = (start - key.offset) >>
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inode->i_blkbits;
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old_num = btrfs_file_extent_num_blocks(extent);
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*hint_block =
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btrfs_file_extent_disk_blocknr(extent);
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if (btrfs_file_extent_disk_blocknr(extent)) {
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inode->i_blocks -=
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(old_num - new_num) << 3;
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}
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btrfs_set_file_extent_num_blocks(extent,
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new_num);
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btrfs_mark_buffer_dirty(path->nodes[0]);
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} else {
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WARN_ON(1);
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}
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}
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/* delete the entire extent */
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if (!keep) {
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u64 disk_blocknr = 0;
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u64 disk_num_blocks = 0;
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u64 extent_num_blocks = 0;
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if (found_extent) {
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disk_blocknr =
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btrfs_file_extent_disk_blocknr(extent);
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disk_num_blocks =
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btrfs_file_extent_disk_num_blocks(extent);
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extent_num_blocks =
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btrfs_file_extent_num_blocks(extent);
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*hint_block =
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btrfs_file_extent_disk_blocknr(extent);
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}
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ret = btrfs_del_item(trans, root, path);
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/* TODO update progress marker and return */
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BUG_ON(ret);
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btrfs_release_path(root, path);
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extent = NULL;
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if (found_extent && disk_blocknr != 0) {
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inode->i_blocks -= extent_num_blocks << 3;
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ret = btrfs_free_extent(trans, root,
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disk_blocknr,
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disk_num_blocks, 0);
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}
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BUG_ON(ret);
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if (!bookend && search_start >= end) {
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ret = 0;
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goto out;
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}
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if (!bookend)
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continue;
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}
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/* create bookend, splitting the extent in two */
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if (bookend && found_extent) {
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struct btrfs_key ins;
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ins.objectid = inode->i_ino;
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ins.offset = end;
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ins.flags = 0;
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btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
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btrfs_release_path(root, path);
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ret = btrfs_insert_empty_item(trans, root, path, &ins,
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sizeof(*extent));
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if (ret) {
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btrfs_print_leaf(root, btrfs_buffer_leaf(path->nodes[0]));
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printk("got %d on inserting %Lu %u %Lu start %Lu end %Lu found %Lu %Lu keep was %d\n", ret , ins.objectid, ins.flags, ins.offset, start, end, key.offset, extent_end, keep);
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}
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BUG_ON(ret);
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extent = btrfs_item_ptr(
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btrfs_buffer_leaf(path->nodes[0]),
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path->slots[0],
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struct btrfs_file_extent_item);
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btrfs_set_file_extent_disk_blocknr(extent,
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btrfs_file_extent_disk_blocknr(&old));
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btrfs_set_file_extent_disk_num_blocks(extent,
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btrfs_file_extent_disk_num_blocks(&old));
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|
|
btrfs_set_file_extent_offset(extent,
|
|
btrfs_file_extent_offset(&old) +
|
|
((end - key.offset) >> inode->i_blkbits));
|
|
WARN_ON(btrfs_file_extent_num_blocks(&old) <
|
|
(extent_end - end) >> inode->i_blkbits);
|
|
btrfs_set_file_extent_num_blocks(extent,
|
|
(extent_end - end) >> inode->i_blkbits);
|
|
|
|
btrfs_set_file_extent_type(extent,
|
|
BTRFS_FILE_EXTENT_REG);
|
|
btrfs_set_file_extent_generation(extent,
|
|
btrfs_file_extent_generation(&old));
|
|
btrfs_mark_buffer_dirty(path->nodes[0]);
|
|
if (btrfs_file_extent_disk_blocknr(&old) != 0) {
|
|
inode->i_blocks +=
|
|
btrfs_file_extent_num_blocks(extent) << 3;
|
|
}
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* this gets pages into the page cache and locks them down
|
|
*/
|
|
static int prepare_pages(struct btrfs_root *root,
|
|
struct file *file,
|
|
struct page **pages,
|
|
size_t num_pages,
|
|
loff_t pos,
|
|
unsigned long first_index,
|
|
unsigned long last_index,
|
|
size_t write_bytes)
|
|
{
|
|
int i;
|
|
unsigned long index = pos >> PAGE_CACHE_SHIFT;
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
int err = 0;
|
|
u64 num_blocks;
|
|
u64 start_pos;
|
|
|
|
start_pos = pos & ~((u64)root->blocksize - 1);
|
|
num_blocks = (write_bytes + pos - start_pos + root->blocksize - 1) >>
|
|
inode->i_blkbits;
|
|
|
|
memset(pages, 0, num_pages * sizeof(struct page *));
|
|
|
|
for (i = 0; i < num_pages; i++) {
|
|
pages[i] = grab_cache_page(inode->i_mapping, index + i);
|
|
if (!pages[i]) {
|
|
err = -ENOMEM;
|
|
BUG_ON(1);
|
|
}
|
|
cancel_dirty_page(pages[i], PAGE_CACHE_SIZE);
|
|
wait_on_page_writeback(pages[i]);
|
|
set_page_extent_mapped(pages[i]);
|
|
WARN_ON(!PageLocked(pages[i]));
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
loff_t pos;
|
|
size_t num_written = 0;
|
|
int err = 0;
|
|
int ret = 0;
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct page **pages = NULL;
|
|
int nrptrs;
|
|
struct page *pinned[2];
|
|
unsigned long first_index;
|
|
unsigned long last_index;
|
|
|
|
nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE,
|
|
PAGE_CACHE_SIZE / (sizeof(struct page *)));
|
|
pinned[0] = NULL;
|
|
pinned[1] = NULL;
|
|
if (file->f_flags & O_DIRECT)
|
|
return -EINVAL;
|
|
pos = *ppos;
|
|
vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
|
|
current->backing_dev_info = inode->i_mapping->backing_dev_info;
|
|
err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
|
|
if (err)
|
|
goto out;
|
|
if (count == 0)
|
|
goto out;
|
|
err = remove_suid(file->f_path.dentry);
|
|
if (err)
|
|
goto out;
|
|
file_update_time(file);
|
|
|
|
pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
first_index = pos >> PAGE_CACHE_SHIFT;
|
|
last_index = (pos + count) >> PAGE_CACHE_SHIFT;
|
|
|
|
/*
|
|
* there are lots of better ways to do this, but this code
|
|
* makes sure the first and last page in the file range are
|
|
* up to date and ready for cow
|
|
*/
|
|
if ((pos & (PAGE_CACHE_SIZE - 1))) {
|
|
pinned[0] = grab_cache_page(inode->i_mapping, first_index);
|
|
if (!PageUptodate(pinned[0])) {
|
|
ret = btrfs_readpage(NULL, pinned[0]);
|
|
BUG_ON(ret);
|
|
wait_on_page_locked(pinned[0]);
|
|
} else {
|
|
unlock_page(pinned[0]);
|
|
}
|
|
}
|
|
if ((pos + count) & (PAGE_CACHE_SIZE - 1)) {
|
|
pinned[1] = grab_cache_page(inode->i_mapping, last_index);
|
|
if (!PageUptodate(pinned[1])) {
|
|
ret = btrfs_readpage(NULL, pinned[1]);
|
|
BUG_ON(ret);
|
|
wait_on_page_locked(pinned[1]);
|
|
} else {
|
|
unlock_page(pinned[1]);
|
|
}
|
|
}
|
|
|
|
while(count > 0) {
|
|
size_t offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
size_t write_bytes = min(count, nrptrs *
|
|
(size_t)PAGE_CACHE_SIZE -
|
|
offset);
|
|
size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
|
|
PAGE_CACHE_SHIFT;
|
|
|
|
WARN_ON(num_pages > nrptrs);
|
|
memset(pages, 0, sizeof(pages));
|
|
ret = prepare_pages(root, file, pages, num_pages,
|
|
pos, first_index, last_index,
|
|
write_bytes);
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = btrfs_copy_from_user(pos, num_pages,
|
|
write_bytes, pages, buf);
|
|
if (ret) {
|
|
btrfs_drop_pages(pages, num_pages);
|
|
goto out;
|
|
}
|
|
|
|
ret = dirty_and_release_pages(NULL, root, file, pages,
|
|
num_pages, pos, write_bytes);
|
|
btrfs_drop_pages(pages, num_pages);
|
|
if (ret)
|
|
goto out;
|
|
|
|
buf += write_bytes;
|
|
count -= write_bytes;
|
|
pos += write_bytes;
|
|
num_written += write_bytes;
|
|
|
|
balance_dirty_pages_ratelimited_nr(inode->i_mapping, num_pages);
|
|
btrfs_btree_balance_dirty(root, 1);
|
|
cond_resched();
|
|
}
|
|
mutex_unlock(&inode->i_mutex);
|
|
out:
|
|
kfree(pages);
|
|
if (pinned[0])
|
|
page_cache_release(pinned[0]);
|
|
if (pinned[1])
|
|
page_cache_release(pinned[1]);
|
|
*ppos = pos;
|
|
current->backing_dev_info = NULL;
|
|
return num_written ? num_written : err;
|
|
}
|
|
|
|
static int btrfs_sync_file(struct file *file,
|
|
struct dentry *dentry, int datasync)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
int ret = 0;
|
|
struct btrfs_trans_handle *trans;
|
|
|
|
/*
|
|
* check the transaction that last modified this inode
|
|
* and see if its already been committed
|
|
*/
|
|
mutex_lock(&root->fs_info->fs_mutex);
|
|
if (!BTRFS_I(inode)->last_trans)
|
|
goto out;
|
|
mutex_lock(&root->fs_info->trans_mutex);
|
|
if (BTRFS_I(inode)->last_trans <=
|
|
root->fs_info->last_trans_committed) {
|
|
BTRFS_I(inode)->last_trans = 0;
|
|
mutex_unlock(&root->fs_info->trans_mutex);
|
|
goto out;
|
|
}
|
|
mutex_unlock(&root->fs_info->trans_mutex);
|
|
|
|
/*
|
|
* ok we haven't committed the transaction yet, lets do a commit
|
|
*/
|
|
trans = btrfs_start_transaction(root, 1);
|
|
if (!trans) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
ret = btrfs_commit_transaction(trans, root);
|
|
out:
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
return ret > 0 ? EIO : ret;
|
|
}
|
|
|
|
static struct vm_operations_struct btrfs_file_vm_ops = {
|
|
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
|
|
.nopage = filemap_nopage,
|
|
.populate = filemap_populate,
|
|
#else
|
|
.fault = filemap_fault,
|
|
#endif
|
|
.page_mkwrite = btrfs_page_mkwrite,
|
|
};
|
|
|
|
static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
|
|
{
|
|
vma->vm_ops = &btrfs_file_vm_ops;
|
|
file_accessed(filp);
|
|
return 0;
|
|
}
|
|
|
|
struct file_operations btrfs_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read = do_sync_read,
|
|
.aio_read = generic_file_aio_read,
|
|
.write = btrfs_file_write,
|
|
.mmap = btrfs_file_mmap,
|
|
.open = generic_file_open,
|
|
.fsync = btrfs_sync_file,
|
|
.unlocked_ioctl = btrfs_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = btrfs_ioctl,
|
|
#endif
|
|
};
|
|
|