return 0;
}
+/*
+ * At the moment we always log all xattrs. This is to figure out at log replay
+ * time which xattrs must have their deletion replayed. If a xattr is missing
+ * in the log tree and exists in the fs/subvol tree, we delete it. This is
+ * because if a xattr is deleted, the inode is fsynced and a power failure
+ * happens, causing the log to be replayed the next time the fs is mounted,
+ * we want the xattr to not exist anymore (same behaviour as other filesystems
+ * with a journal, ext3/4, xfs, f2fs, etc).
+ */
+static int btrfs_log_all_xattrs(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ struct btrfs_path *path,
+ struct btrfs_path *dst_path)
+{
+ int ret;
+ struct btrfs_key key;
+ const u64 ino = btrfs_ino(inode);
+ int ins_nr = 0;
+ int start_slot = 0;
+
+ key.objectid = ino;
+ key.type = BTRFS_XATTR_ITEM_KEY;
+ key.offset = 0;
+
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
+ return ret;
+
+ while (true) {
+ int slot = path->slots[0];
+ struct extent_buffer *leaf = path->nodes[0];
+ int nritems = btrfs_header_nritems(leaf);
+
+ if (slot >= nritems) {
+ if (ins_nr > 0) {
+ u64 last_extent = 0;
+
+ ret = copy_items(trans, inode, dst_path, path,
+ &last_extent, start_slot,
+ ins_nr, 1, 0);
+ /* can't be 1, extent items aren't processed */
+ ASSERT(ret <= 0);
+ if (ret < 0)
+ return ret;
+ ins_nr = 0;
+ }
+ ret = btrfs_next_leaf(root, path);
+ if (ret < 0)
+ return ret;
+ else if (ret > 0)
+ break;
+ continue;
+ }
+
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+ if (key.objectid != ino || key.type != BTRFS_XATTR_ITEM_KEY)
+ break;
+
+ if (ins_nr == 0)
+ start_slot = slot;
+ ins_nr++;
+ path->slots[0]++;
+ cond_resched();
+ }
+ if (ins_nr > 0) {
+ u64 last_extent = 0;
+
+ ret = copy_items(trans, inode, dst_path, path,
+ &last_extent, start_slot,
+ ins_nr, 1, 0);
+ /* can't be 1, extent items aren't processed */
+ ASSERT(ret <= 0);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+/*
+ * If the no holes feature is enabled we need to make sure any hole between the
+ * last extent and the i_size of our inode is explicitly marked in the log. This
+ * is to make sure that doing something like:
+ *
+ * 1) create file with 128Kb of data
+ * 2) truncate file to 64Kb
+ * 3) truncate file to 256Kb
+ * 4) fsync file
+ * 5) <crash/power failure>
+ * 6) mount fs and trigger log replay
+ *
+ * Will give us a file with a size of 256Kb, the first 64Kb of data match what
+ * the file had in its first 64Kb of data at step 1 and the last 192Kb of the
+ * file correspond to a hole. The presence of explicit holes in a log tree is
+ * what guarantees that log replay will remove/adjust file extent items in the
+ * fs/subvol tree.
+ *
+ * Here we do not need to care about holes between extents, that is already done
+ * by copy_items(). We also only need to do this in the full sync path, where we
+ * lookup for extents from the fs/subvol tree only. In the fast path case, we
+ * lookup the list of modified extent maps and if any represents a hole, we
+ * insert a corresponding extent representing a hole in the log tree.
+ */
+static int btrfs_log_trailing_hole(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ struct btrfs_path *path)
+{
+ int ret;
+ struct btrfs_key key;
+ u64 hole_start;
+ u64 hole_size;
+ struct extent_buffer *leaf;
+ struct btrfs_root *log = root->log_root;
+ const u64 ino = btrfs_ino(inode);
+ const u64 i_size = i_size_read(inode);
+
+ if (!btrfs_fs_incompat(root->fs_info, NO_HOLES))
+ return 0;
+
+ key.objectid = ino;
+ key.type = BTRFS_EXTENT_DATA_KEY;
+ key.offset = (u64)-1;
+
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ ASSERT(ret != 0);
+ if (ret < 0)
+ return ret;
+
+ ASSERT(path->slots[0] > 0);
+ path->slots[0]--;
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+
+ if (key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY) {
+ /* inode does not have any extents */
+ hole_start = 0;
+ hole_size = i_size;
+ } else {
+ struct btrfs_file_extent_item *extent;
+ u64 len;
+
+ /*
+ * If there's an extent beyond i_size, an explicit hole was
+ * already inserted by copy_items().
+ */
+ if (key.offset >= i_size)
+ return 0;
+
+ extent = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_file_extent_item);
+
+ if (btrfs_file_extent_type(leaf, extent) ==
+ BTRFS_FILE_EXTENT_INLINE) {
+ len = btrfs_file_extent_inline_len(leaf,
+ path->slots[0],
+ extent);
+ ASSERT(len == i_size);
+ return 0;
+ }
+
+ len = btrfs_file_extent_num_bytes(leaf, extent);
+ /* Last extent goes beyond i_size, no need to log a hole. */
+ if (key.offset + len > i_size)
+ return 0;
+ hole_start = key.offset + len;
+ hole_size = i_size - hole_start;
+ }
+ btrfs_release_path(path);
+
+ /* Last extent ends at i_size. */
+ if (hole_size == 0)
+ return 0;
+
+ hole_size = ALIGN(hole_size, root->sectorsize);
+ ret = btrfs_insert_file_extent(trans, log, ino, hole_start, 0, 0,
+ hole_size, 0, hole_size, 0, 0, 0);
+ return ret;
+}
+
/* log a single inode in the tree log.
* At least one parent directory for this inode must exist in the tree
* or be logged already.
u64 ino = btrfs_ino(inode);
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
u64 logged_isize = 0;
+ bool need_log_inode_item = true;
path = btrfs_alloc_path();
if (!path)
} else {
if (inode_only == LOG_INODE_ALL)
fast_search = true;
- ret = log_inode_item(trans, log, dst_path, inode);
- if (ret) {
- err = ret;
- goto out_unlock;
- }
goto log_extents;
}
if (min_key.type > max_key.type)
break;
+ if (min_key.type == BTRFS_INODE_ITEM_KEY)
+ need_log_inode_item = false;
+
+ /* Skip xattrs, we log them later with btrfs_log_all_xattrs() */
+ if (min_key.type == BTRFS_XATTR_ITEM_KEY) {
+ if (ins_nr == 0)
+ goto next_slot;
+ ret = copy_items(trans, inode, dst_path, path,
+ &last_extent, ins_start_slot,
+ ins_nr, inode_only, logged_isize);
+ if (ret < 0) {
+ err = ret;
+ goto out_unlock;
+ }
+ ins_nr = 0;
+ if (ret) {
+ btrfs_release_path(path);
+ continue;
+ }
+ goto next_slot;
+ }
+
src = path->nodes[0];
if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
ins_nr++;
ins_nr = 0;
}
+ btrfs_release_path(path);
+ btrfs_release_path(dst_path);
+ err = btrfs_log_all_xattrs(trans, root, inode, path, dst_path);
+ if (err)
+ goto out_unlock;
+ if (max_key.type >= BTRFS_EXTENT_DATA_KEY && !fast_search) {
+ btrfs_release_path(path);
+ btrfs_release_path(dst_path);
+ err = btrfs_log_trailing_hole(trans, root, inode, path);
+ if (err)
+ goto out_unlock;
+ }
log_extents:
btrfs_release_path(path);
btrfs_release_path(dst_path);
+ if (need_log_inode_item) {
+ err = log_inode_item(trans, log, dst_path, inode);
+ if (err)
+ goto out_unlock;
+ }
if (fast_search) {
/*
* Some ordered extents started by fsync might have completed
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