btrfs: replace many BUG_ONs with proper error handling
btrfs currently handles most errors with BUG_ON. This patch is a work-in-
progress but aims to handle most errors other than internal logic
errors and ENOMEM more gracefully.
This iteration prevents most crashes but can run into lockups with
the page lock on occasion when the timing "works out."
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index ee15d88..7ca46e6 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -178,7 +178,7 @@
tsk = kthread_run(caching_kthread, root, "btrfs-ino-cache-%llu\n",
root->root_key.objectid);
- BUG_ON(IS_ERR(tsk));
+ BUG_ON(IS_ERR(tsk)); /* -ENOMEM */
}
int btrfs_find_free_ino(struct btrfs_root *root, u64 *objectid)
@@ -271,7 +271,7 @@
break;
info = rb_entry(n, struct btrfs_free_space, offset_index);
- BUG_ON(info->bitmap);
+ BUG_ON(info->bitmap); /* Logic error */
if (info->offset > root->cache_progress)
goto free;
@@ -443,13 +443,13 @@
trans->bytes_reserved, 1);
again:
inode = lookup_free_ino_inode(root, path);
- if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
+ if (IS_ERR(inode) && (PTR_ERR(inode) != -ENOENT || retry)) {
ret = PTR_ERR(inode);
goto out_release;
}
if (IS_ERR(inode)) {
- BUG_ON(retry);
+ BUG_ON(retry); /* Logic error */
retry = true;
ret = create_free_ino_inode(root, trans, path);
@@ -460,12 +460,17 @@
BTRFS_I(inode)->generation = 0;
ret = btrfs_update_inode(trans, root, inode);
- WARN_ON(ret);
+ if (ret) {
+ btrfs_abort_transaction(trans, root, ret);
+ goto out_put;
+ }
if (i_size_read(inode) > 0) {
ret = btrfs_truncate_free_space_cache(root, trans, path, inode);
- if (ret)
+ if (ret) {
+ btrfs_abort_transaction(trans, root, ret);
goto out_put;
+ }
}
spin_lock(&root->cache_lock);
@@ -532,7 +537,7 @@
ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
if (ret < 0)
goto error;
- BUG_ON(ret == 0);
+ BUG_ON(ret == 0); /* Corruption */
if (path->slots[0] > 0) {
slot = path->slots[0] - 1;
l = path->nodes[0];