INIT_LIST_HEAD(&extents);
+ down_write(&BTRFS_I(inode)->dio_sem);
write_lock(&tree->lock);
test_gen = root->fs_info->last_trans_committed;
}
list_sort(NULL, &extents, extent_cmp);
+ btrfs_get_logged_extents(inode, logged_list, start, end);
/*
- * Collect any new ordered extents within the range. This is to
- * prevent logging file extent items without waiting for the disk
- * location they point to being written. We do this only to deal
- * with races against concurrent lockless direct IO writes.
+ * Some ordered extents started by fsync might have completed
+ * before we could collect them into the list logged_list, which
+ * means they're gone, not in our logged_list nor in the inode's
+ * ordered tree. We want the application/user space to know an
+ * error happened while attempting to persist file data so that
+ * it can take proper action. If such error happened, we leave
+ * without writing to the log tree and the fsync must report the
+ * file data write error and not commit the current transaction.
*/
- btrfs_get_logged_extents(inode, logged_list, start, end);
+ ret = btrfs_inode_check_errors(inode);
+ if (ret)
+ ctx->io_err = ret;
process:
while (!list_empty(&extents)) {
em = list_entry(extents.next, struct extent_map, list);
}
WARN_ON(!list_empty(&extents));
write_unlock(&tree->lock);
+ up_write(&BTRFS_I(inode)->dio_sem);
btrfs_release_path(path);
return ret;
return ret;
}
+/*
+ * When we are logging a new inode X, check if it doesn't have a reference that
+ * matches the reference from some other inode Y created in a past transaction
+ * and that was renamed in the current transaction. If we don't do this, then at
+ * log replay time we can lose inode Y (and all its files if it's a directory):
+ *
+ * mkdir /mnt/x
+ * echo "hello world" > /mnt/x/foobar
+ * sync
+ * mv /mnt/x /mnt/y
+ * mkdir /mnt/x # or touch /mnt/x
+ * xfs_io -c fsync /mnt/x
+ * <power fail>
+ * mount fs, trigger log replay
+ *
+ * After the log replay procedure, we would lose the first directory and all its
+ * files (file foobar).
+ * For the case where inode Y is not a directory we simply end up losing it:
+ *
+ * echo "123" > /mnt/foo
+ * sync
+ * mv /mnt/foo /mnt/bar
+ * echo "abc" > /mnt/foo
+ * xfs_io -c fsync /mnt/foo
+ * <power fail>
+ *
+ * We also need this for cases where a snapshot entry is replaced by some other
+ * entry (file or directory) otherwise we end up with an unreplayable log due to
+ * attempts to delete the snapshot entry (entry of type BTRFS_ROOT_ITEM_KEY) as
+ * if it were a regular entry:
+ *
+ * mkdir /mnt/x
+ * btrfs subvolume snapshot /mnt /mnt/x/snap
+ * btrfs subvolume delete /mnt/x/snap
+ * rmdir /mnt/x
+ * mkdir /mnt/x
+ * fsync /mnt/x or fsync some new file inside it
+ * <power fail>
+ *
+ * The snapshot delete, rmdir of x, mkdir of a new x and the fsync all happen in
+ * the same transaction.
+ */
+static int btrfs_check_ref_name_override(struct extent_buffer *eb,
+ const int slot,
+ const struct btrfs_key *key,
+ struct inode *inode)
+{
+ int ret;
+ struct btrfs_path *search_path;
+ char *name = NULL;
+ u32 name_len = 0;
+ u32 item_size = btrfs_item_size_nr(eb, slot);
+ u32 cur_offset = 0;
+ unsigned long ptr = btrfs_item_ptr_offset(eb, slot);
+
+ search_path = btrfs_alloc_path();
+ if (!search_path)
+ return -ENOMEM;
+ search_path->search_commit_root = 1;
+ search_path->skip_locking = 1;
+
+ while (cur_offset < item_size) {
+ u64 parent;
+ u32 this_name_len;
+ u32 this_len;
+ unsigned long name_ptr;
+ struct btrfs_dir_item *di;
+
+ if (key->type == BTRFS_INODE_REF_KEY) {
+ struct btrfs_inode_ref *iref;
+
+ iref = (struct btrfs_inode_ref *)(ptr + cur_offset);
+ parent = key->offset;
+ this_name_len = btrfs_inode_ref_name_len(eb, iref);
+ name_ptr = (unsigned long)(iref + 1);
+ this_len = sizeof(*iref) + this_name_len;
+ } else {
+ struct btrfs_inode_extref *extref;
+
+ extref = (struct btrfs_inode_extref *)(ptr +
+ cur_offset);
+ parent = btrfs_inode_extref_parent(eb, extref);
+ this_name_len = btrfs_inode_extref_name_len(eb, extref);
+ name_ptr = (unsigned long)&extref->name;
+ this_len = sizeof(*extref) + this_name_len;
+ }
+
+ if (this_name_len > name_len) {
+ char *new_name;
+
+ new_name = krealloc(name, this_name_len, GFP_NOFS);
+ if (!new_name) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ name_len = this_name_len;
+ name = new_name;
+ }
+
+ read_extent_buffer(eb, name, name_ptr, this_name_len);
+ di = btrfs_lookup_dir_item(NULL, BTRFS_I(inode)->root,
+ search_path, parent,
+ name, this_name_len, 0);
+ if (di && !IS_ERR(di)) {
+ ret = 1;
+ goto out;
+ } else if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto out;
+ }
+ btrfs_release_path(search_path);
+
+ cur_offset += this_len;
+ }
+ ret = 0;
+out:
+ btrfs_free_path(search_path);
+ kfree(name);
+ 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.
mutex_lock(&BTRFS_I(inode)->log_mutex);
- /*
- * Collect ordered extents only if we are logging data. This is to
- * ensure a subsequent request to log this inode in LOG_INODE_ALL mode
- * will process the ordered extents if they still exists at the time,
- * because when we collect them we test and set for the flag
- * BTRFS_ORDERED_LOGGED to prevent multiple log requests to process the
- * same ordered extents. The consequence for the LOG_INODE_ALL log mode
- * not processing the ordered extents is that we end up logging the
- * corresponding file extent items, based on the extent maps in the
- * inode's extent_map_tree's modified_list, without logging the
- * respective checksums (since the may still be only attached to the
- * ordered extents and have not been inserted in the csum tree by
- * btrfs_finish_ordered_io() yet).
- */
- if (inode_only == LOG_INODE_ALL)
- btrfs_get_logged_extents(inode, &logged_list, start, end);
-
/*
* a brute force approach to making sure we get the most uptodate
* copies of everything.
if (min_key.type == BTRFS_INODE_ITEM_KEY)
need_log_inode_item = false;
+ if ((min_key.type == BTRFS_INODE_REF_KEY ||
+ min_key.type == BTRFS_INODE_EXTREF_KEY) &&
+ BTRFS_I(inode)->generation == trans->transid) {
+ ret = btrfs_check_ref_name_override(path->nodes[0],
+ path->slots[0],
+ &min_key, inode);
+ if (ret < 0) {
+ err = ret;
+ goto out_unlock;
+ } else if (ret > 0) {
+ err = 1;
+ btrfs_set_log_full_commit(root->fs_info, trans);
+ goto out_unlock;
+ }
+ }
+
/* Skip xattrs, we log them later with btrfs_log_all_xattrs() */
if (min_key.type == BTRFS_XATTR_ITEM_KEY) {
if (ins_nr == 0)
goto out_unlock;
}
if (fast_search) {
- /*
- * Some ordered extents started by fsync might have completed
- * before we collected the ordered extents in logged_list, which
- * means they're gone, not in our logged_list nor in the inode's
- * ordered tree. We want the application/user space to know an
- * error happened while attempting to persist file data so that
- * it can take proper action. If such error happened, we leave
- * without writing to the log tree and the fsync must report the
- * file data write error and not commit the current transaction.
- */
- err = btrfs_inode_check_errors(inode);
- if (err) {
- ctx->io_err = err;
- goto out_unlock;
- }
ret = btrfs_log_changed_extents(trans, root, inode, dst_path,
&logged_list, ctx, start, end);
if (ret) {
}
ctx->log_new_dentries = false;
- if (type == BTRFS_FT_DIR)
+ if (type == BTRFS_FT_DIR || type == BTRFS_FT_SYMLINK)
log_mode = LOG_INODE_ALL;
btrfs_release_path(path);
ret = btrfs_log_inode(trans, root, di_inode,
if (IS_ERR(dir_inode))
continue;
+ if (ctx)
+ ctx->log_new_dentries = false;
ret = btrfs_log_inode(trans, root, dir_inode,
LOG_INODE_ALL, 0, LLONG_MAX, ctx);
if (!ret &&
btrfs_must_commit_transaction(trans, dir_inode))
ret = 1;
+ if (!ret && ctx && ctx->log_new_dentries)
+ ret = log_new_dir_dentries(trans, root,
+ dir_inode, ctx);
iput(dir_inode);
if (ret)
goto out;
* into the file. When the file is logged we check it and
* don't log the parents if the file is fully on disk.
*/
- if (S_ISREG(inode->i_mode)) {
- mutex_lock(&BTRFS_I(inode)->log_mutex);
- BTRFS_I(inode)->last_unlink_trans = trans->transid;
- mutex_unlock(&BTRFS_I(inode)->log_mutex);
- }
+ mutex_lock(&BTRFS_I(inode)->log_mutex);
+ BTRFS_I(inode)->last_unlink_trans = trans->transid;
+ mutex_unlock(&BTRFS_I(inode)->log_mutex);
/*
* if this directory was already logged any new
projects / deliverable / linux.git / blobdiff