From f9d102efdc87f9c142157f16e443fb2c610c5317 Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Thu, 5 Sep 2013 15:53:34 +0900 Subject: [PATCH] btrfs-progs: error if device for mkfs is too small Eric pointed out that mkfs abort if specified volume is too small: # truncate --size=2m testfile # ./mkfs.btrfs testfile : SMALL VOLUME: forcing mixed metadata/data groups mkfs.btrfs: volumes.c:852: btrfs_alloc_chunk: Assertion `!(ret)' failed. Aborted (core dumped) As the first step to fix problems around there, let mkfs to report error if the size of target volume is less than the size of the first system block group, BTRFS_MKFS_SYSTEM_GROUP_SIZE (= 4MB). Reported-by: Eric Sandeen Signed-off-by: Hidetoshi Seto Signed-off-by: David Sterba Signed-off-by: Chris Mason --- mkfs.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/mkfs.c b/mkfs.c index 6abd3f89..b442fc0a 100644 --- a/mkfs.c +++ b/mkfs.c @@ -1513,6 +1513,11 @@ int main(int ac, char **av) dev_block_count = block_count; } + /* To create the first block group and chunk 0 in make_btrfs */ + if (dev_block_count < BTRFS_MKFS_SYSTEM_GROUP_SIZE) { + fprintf(stderr, "device is too small to make filesystem\n"); + exit(1); + } blocks[0] = BTRFS_SUPER_INFO_OFFSET; for (i = 1; i < 7; i++) {