On 14.09.2018 10:25, Qu Wenruo wrote:
> When convert failed, the error messsage would look like:
>
> create btrfs filesystem:
> blocksize: 4096
> nodesize: 16384
> features: extref, skinny-metadata (default)
> creating ext2 image file
> ERROR: failed to create ext2_saved/image: -1
> WARNING: an error occurred during conversion, filesystem is partially
> created but not finalized and not mountable
>
> We can only know something wrong happened during "ext2_saved/image" file
> creation, but unable to know what exactly went wrong.
>
> This patch will add the following error messages for create_image() and
> its callee:
>
> 1) Sanity test error
> 2) Csum calculation error
> 3) Free ino number allocation error
> 4) Inode creation error
> 5) Inode mode change error
> 6) Inode link error
>
> With all these error messages, we should be pretty easy to locate the
> error without extra debugging.
>
> Reported-by: Serhat Sevki Dincer
> Signed-off-by: Qu Wenruo
Reviewed-by: Nikolay Borisov
> ---
> convert/main.c | 37 ++---
> 1 file changed, 30 insertions(+), 7 deletions(-)
>
> diff --git a/convert/main.c b/convert/main.c
> index 3736a14955d1..f100699b652c 100644
> --- a/convert/main.c
> +++ b/convert/main.c
> @@ -290,10 +290,16 @@ static int create_image_file_range(struct
> btrfs_trans_handle *trans,
> if (disk_bytenr) {
> /* Check if the range is in a data block group */
> bg_cache = btrfs_lookup_block_group(root->fs_info, bytenr);
> - if (!bg_cache)
> + if (!bg_cache) {
> + error("missing data block for bytenr %llu", bytenr);
> return -ENOENT;
> - if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_DATA))
> + }
> + if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_DATA)) {
> + error(
> + "data bytenr %llu is covered by non-data block group %llu flags 0x%llu",
> + bytenr, bg_cache->key.objectid, bg_cache->flags);
> return -EINVAL;
> + }
>
> /* The extent should never cross block group boundary */
> len = min_t(u64, len, bg_cache->key.objectid +
> @@ -310,8 +316,13 @@ static int create_image_file_range(struct
> btrfs_trans_handle *trans,
> if (ret < 0)
> return ret;
>
> - if (datacsum)
> + if (datacsum) {
> ret = csum_disk_extent(trans, root, bytenr, len);
> + if (ret < 0)
> + error(
> + "failed to calculate csum for bytenr %llu len %llu, %s\n",
> + bytenr, len, strerror(-ret));
> + }
> *ret_len = len;
> return ret;
> }
> @@ -759,18 +770,30 @@ static int create_image(struct btrfs_root *root,
>
> ret = btrfs_find_free_objectid(trans, root, BTRFS_FIRST_FREE_OBJECTID,
> );
> - if (ret < 0)
> + if (ret < 0) {
> + error("failed to find free objectid for root %llu, %s",
> + root->root_key.objectid, strerror(-ret));
> goto out;
> + }
> ret = btrfs_new_inode(trans, root, ino, 0400 | S_IFREG);
> - if (ret < 0)
> + if (ret < 0) {
> + error("failed to create new inode for root %llu, %s",
> + root->root_key.objectid, strerror(-ret));
> goto out;
> + }
> ret = btrfs_change_inode_flags(trans, root, ino, flags);
> - if (ret < 0)
> + if (ret < 0) {
> + error("failed to change inode flag for ino %llu root %llu, %s",
> + ino, root->root_key.objectid, strerror(-ret));
> goto out;
> + }
> ret = btrfs_add_link(trans, root, ino, BTRFS_FIRST_FREE_OBJECTID, name,
>strlen(name), BTRFS_FT_REG_FILE, NULL, 1, 0);
> - if (ret < 0)
> + if (ret < 0) {
> + error("failed to link ino %llu to '/%s' in root %llu, %s",
> + ino, name, root->root_key.objectid, strerror(-ret));
> goto out;
> + }
>
> key.objectid = ino;
> key.type = BTRFS_INODE_ITEM_KEY;
>