From 607d432da0542e84ddcd358adfddac6f68500e3d Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Tue, 2 Dec 2008 07:17:45 -0500 Subject: Btrfs: add support for multiple csum algorithms This patch gives us the space we will need in order to have different csum algorithims at some point in the future. We save the csum algorithim type in the superblock, and use those instead of define's. Signed-off-by: Josef Bacik --- fs/btrfs/disk-io.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index dfd5ba05ce4..3eb7c2576fe 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -176,7 +176,9 @@ void btrfs_csum_final(u32 crc, char *result) static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, int verify) { - char result[BTRFS_CRC32_SIZE]; + u16 csum_size = + btrfs_super_csum_size(&root->fs_info->super_copy); + char *result = NULL; unsigned long len; unsigned long cur_len; unsigned long offset = BTRFS_CSUM_SIZE; @@ -186,6 +188,7 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, unsigned long map_len; int err; u32 crc = ~(u32)0; + unsigned long inline_result; len = buf->len - offset; while(len > 0) { @@ -204,25 +207,37 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, offset += cur_len; unmap_extent_buffer(buf, map_token, KM_USER0); } + if (csum_size > sizeof(inline_result)) { + result = kzalloc(csum_size * sizeof(char), GFP_NOFS); + if (!result) + return 1; + } else { + result = (char *)&inline_result; + } + btrfs_csum_final(crc, result); if (verify) { /* FIXME, this is not good */ - if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) { + if (memcmp_extent_buffer(buf, result, 0, csum_size)) { u32 val; u32 found = 0; - memcpy(&found, result, BTRFS_CRC32_SIZE); + memcpy(&found, result, csum_size); - read_extent_buffer(buf, &val, 0, BTRFS_CRC32_SIZE); + read_extent_buffer(buf, &val, 0, csum_size); printk("btrfs: %s checksum verify failed on %llu " "wanted %X found %X level %d\n", root->fs_info->sb->s_id, buf->start, val, found, btrfs_header_level(buf)); + if (result != (char *)&inline_result) + kfree(result); return 1; } } else { - write_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE); + write_extent_buffer(buf, result, 0, csum_size); } + if (result != (char *)&inline_result) + kfree(result); return 0; } -- cgit