From c7c144db531fda414e532adac56e965ce332e2a5 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Wed, 7 Dec 2011 10:39:22 +0800 Subject: [PATCH] Btrfs: update global block_rsv when creating a new block group A bug was triggered while using seed device: # mkfs.btrfs /dev/loop1 # btrfstune -S 1 /dev/loop1 # mount -o /dev/loop1 /mnt # btrfs dev add /dev/loop2 /mnt btrfs: block rsv returned -28 ------------[ cut here ]------------ WARNING: at fs/btrfs/extent-tree.c:5969 btrfs_alloc_free_block+0x166/0x396 [btrfs]() ... Call Trace: ... [] btrfs_cow_block+0x101/0x147 [btrfs] [] btrfs_search_slot+0x1b8/0x55f [btrfs] [] btrfs_insert_empty_items+0x42/0x7f [btrfs] [] btrfs_insert_item+0x40/0x7e [btrfs] [] btrfs_make_block_group+0x243/0x2aa [btrfs] [] __btrfs_alloc_chunk+0x672/0x70e [btrfs] [] init_first_rw_device+0x77/0x13c [btrfs] [] btrfs_init_new_device+0x664/0x9fd [btrfs] [] btrfs_ioctl+0x694/0xdbe [btrfs] [] do_vfs_ioctl+0x496/0x4cc [] sys_ioctl+0x33/0x4f [] sysenter_do_call+0x12/0x38 ---[ end trace 906adac595facc7d ]--- Since seed device is readonly, there's no usable space in the filesystem. Afterwards we add a sprout device to it, and the kernel creates a METADATA block group and a SYSTEM block group where comes free space we can reserve, but we still get revervation failure because the global block_rsv hasn't been updated accordingly. Signed-off-by: Li Zefan --- fs/btrfs/extent-tree.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 5b53479ce07b..bf30f670cda9 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7446,6 +7446,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, ret = update_space_info(root->fs_info, cache->flags, size, bytes_used, &cache->space_info); BUG_ON(ret); + update_global_block_rsv(root->fs_info); spin_lock(&cache->space_info->lock); cache->space_info->bytes_readonly += cache->bytes_super; -- 2.34.1