Btrfs: Add file data csums back in via hooks in the extent map code
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 483eea6..3ee6b2f 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -52,6 +52,7 @@
static struct address_space_operations btrfs_aops;
static struct address_space_operations btrfs_symlink_aops;
static struct file_operations btrfs_dir_file_operations;
+static struct extent_map_ops btrfs_extent_map_ops;
static struct kmem_cache *btrfs_inode_cachep;
struct kmem_cache *btrfs_trans_handle_cachep;
@@ -103,6 +104,90 @@
return ret;
}
+int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end)
+{
+ struct inode *inode = page->mapping->host;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+ char *kaddr;
+ int ret;
+ u64 page_start = page->index << PAGE_CACHE_SHIFT;
+ size_t offset = start - page_start;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+ kaddr = kmap(page);
+ btrfs_csum_file_block(trans, root, inode->i_ino,
+ start, kaddr + offset, end - start + 1);
+ kunmap(page);
+ ret = btrfs_end_transaction(trans, root);
+ BUG_ON(ret);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ return ret;
+}
+
+int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
+{
+ int ret = 0;
+ struct inode *inode = page->mapping->host;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ struct btrfs_csum_item *item;
+ struct btrfs_path *path = NULL;
+ u64 private;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ path = btrfs_alloc_path();
+ item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
+ if (IS_ERR(item)) {
+ ret = PTR_ERR(item);
+ /* a csum that isn't present is a preallocated region. */
+ if (ret == -ENOENT || ret == -EFBIG)
+ ret = 0;
+ private = 0;
+ goto out;
+ }
+ memcpy((char *)&private, &item->csum, BTRFS_CRC32_SIZE);
+ set_state_private(em_tree, start, private);
+out:
+ if (path)
+ btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ return ret;
+}
+
+int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end)
+{
+ char csum[BTRFS_CRC32_SIZE];
+ size_t offset = start - (page->index << PAGE_CACHE_SHIFT);
+ struct inode *inode = page->mapping->host;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ char *kaddr;
+ u64 private;
+ int ret;
+
+ ret = get_state_private(em_tree, start, &private);
+ kaddr = kmap_atomic(page, KM_IRQ0);
+ if (ret) {
+ goto zeroit;
+ }
+ ret = btrfs_csum_data(root, kaddr + offset, end - start + 1, csum);
+ BUG_ON(ret);
+ if (memcmp(csum, &private, BTRFS_CRC32_SIZE)) {
+ goto zeroit;
+ }
+ kunmap_atomic(kaddr, KM_IRQ0);
+ return 0;
+
+zeroit:
+ printk("btrfs csum failed ino %lu off %llu\n",
+ page->mapping->host->i_ino, (unsigned long long)start);
+ memset(kaddr + offset, 1, end - start + 1); flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_IRQ0);
+ return 0;
+}
void btrfs_read_locked_inode(struct inode *inode)
{
@@ -155,7 +240,7 @@
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_mapping->a_ops = &btrfs_aops;
- BTRFS_I(inode)->extent_tree.fill_delalloc = run_delalloc_range;
+ BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
break;
@@ -1148,7 +1233,7 @@
inode->i_op = &btrfs_file_inode_operations;
extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
inode->i_mapping, GFP_NOFS);
- BTRFS_I(inode)->extent_tree.fill_delalloc = run_delalloc_range;
+ BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
}
dir->i_sb->s_dirt = 1;
btrfs_update_inode_block_group(trans, inode);
@@ -2286,7 +2371,7 @@
inode->i_op = &btrfs_file_inode_operations;
extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
inode->i_mapping, GFP_NOFS);
- BTRFS_I(inode)->extent_tree.fill_delalloc = run_delalloc_range;
+ BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
}
dir->i_sb->s_dirt = 1;
btrfs_update_inode_block_group(trans, inode);
@@ -2362,6 +2447,13 @@
#endif
};
+static struct extent_map_ops btrfs_extent_map_ops = {
+ .fill_delalloc = run_delalloc_range,
+ .writepage_io_hook = btrfs_writepage_io_hook,
+ .readpage_io_hook = btrfs_readpage_io_hook,
+ .readpage_end_io_hook = btrfs_readpage_end_io_hook,
+};
+
static struct address_space_operations btrfs_aops = {
.readpage = btrfs_readpage,
.writepage = btrfs_writepage,