btrfs: use struct_size to calculate size of raid hash table

The struct_size macro does the same calculation and is safe regarding
overflows. Though we're not expecting them to happen, use the helper for
clarity.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2019-03-29 02:07:02 +01:00
parent dcc3eb9638
commit ee787f9550

View File

@ -206,7 +206,6 @@ int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info)
struct btrfs_stripe_hash *h;
int num_entries = 1 << BTRFS_STRIPE_HASH_TABLE_BITS;
int i;
int table_size;
if (info->stripe_hash_table)
return 0;
@ -218,8 +217,7 @@ int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info)
* Try harder to allocate and fallback to vmalloc to lower the chance
* of a failing mount.
*/
table_size = sizeof(*table) + sizeof(*h) * num_entries;
table = kvzalloc(table_size, GFP_KERNEL);
table = kvzalloc(struct_size(table, table, num_entries), GFP_KERNEL);
if (!table)
return -ENOMEM;