From 79787eaab46121d4713ed03c8fc63b9ec3eaec76 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Mon, 12 Mar 2012 16:03:00 +0100 Subject: 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 --- fs/btrfs/file.c | 45 +++++++++++++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 14 deletions(-) (limited to 'fs/btrfs/file.c') diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 0eb80cc4ec81..d83260d7498f 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -452,7 +452,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, split = alloc_extent_map(); if (!split2) split2 = alloc_extent_map(); - BUG_ON(!split || !split2); + BUG_ON(!split || !split2); /* -ENOMEM */ write_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, len); @@ -494,7 +494,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, split->flags = flags; split->compress_type = em->compress_type; ret = add_extent_mapping(em_tree, split); - BUG_ON(ret); + BUG_ON(ret); /* Logic error */ free_extent_map(split); split = split2; split2 = NULL; @@ -520,7 +520,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, } ret = add_extent_mapping(em_tree, split); - BUG_ON(ret); + BUG_ON(ret); /* Logic error */ free_extent_map(split); split = NULL; } @@ -679,7 +679,7 @@ next_slot: root->root_key.objectid, new_key.objectid, start - extent_offset, 0); - BUG_ON(ret); + BUG_ON(ret); /* -ENOMEM */ *hint_byte = disk_bytenr; } key.offset = start; @@ -754,7 +754,7 @@ next_slot: root->root_key.objectid, key.objectid, key.offset - extent_offset, 0); - BUG_ON(ret); + BUG_ON(ret); /* -ENOMEM */ inode_sub_bytes(inode, extent_end - key.offset); *hint_byte = disk_bytenr; @@ -770,7 +770,10 @@ next_slot: ret = btrfs_del_items(trans, root, path, del_slot, del_nr); - BUG_ON(ret); + if (ret) { + btrfs_abort_transaction(trans, root, ret); + goto out; + } del_nr = 0; del_slot = 0; @@ -782,11 +785,13 @@ next_slot: BUG_ON(1); } - if (del_nr > 0) { + if (!ret && del_nr > 0) { ret = btrfs_del_items(trans, root, path, del_slot, del_nr); - BUG_ON(ret); + if (ret) + btrfs_abort_transaction(trans, root, ret); } +out: btrfs_free_path(path); return ret; } @@ -944,7 +949,10 @@ again: btrfs_release_path(path); goto again; } - BUG_ON(ret < 0); + if (ret < 0) { + btrfs_abort_transaction(trans, root, ret); + goto out; + } leaf = path->nodes[0]; fi = btrfs_item_ptr(leaf, path->slots[0] - 1, @@ -963,7 +971,7 @@ again: ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, ino, orig_offset, 0); - BUG_ON(ret); + BUG_ON(ret); /* -ENOMEM */ if (split == start) { key.offset = start; @@ -990,7 +998,7 @@ again: ret = btrfs_free_extent(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, ino, orig_offset, 0); - BUG_ON(ret); + BUG_ON(ret); /* -ENOMEM */ } other_start = 0; other_end = start; @@ -1007,7 +1015,7 @@ again: ret = btrfs_free_extent(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, ino, orig_offset, 0); - BUG_ON(ret); + BUG_ON(ret); /* -ENOMEM */ } if (del_nr == 0) { fi = btrfs_item_ptr(leaf, path->slots[0], @@ -1025,7 +1033,10 @@ again: btrfs_mark_buffer_dirty(leaf); ret = btrfs_del_items(trans, root, path, del_slot, del_nr); - BUG_ON(ret); + if (ret < 0) { + btrfs_abort_transaction(trans, root, ret); + goto out; + } } out: btrfs_free_path(path); @@ -1666,7 +1677,13 @@ static long btrfs_fallocate(struct file *file, int mode, em = btrfs_get_extent(inode, NULL, 0, cur_offset, alloc_end - cur_offset, 0); - BUG_ON(IS_ERR_OR_NULL(em)); + if (IS_ERR_OR_NULL(em)) { + if (!em) + ret = -ENOMEM; + else + ret = PTR_ERR(em); + break; + } last_byte = min(extent_map_end(em), alloc_end); actual_end = min_t(u64, extent_map_end(em), offset + len); last_byte = (last_byte + mask) & ~mask; -- cgit v1.2.3