From: "Darrick J. Wong" Subject: [PATCH 13/23] ext4: Add new feature to make block group checksums use metadata_csum algorithm Date: Tue, 13 Dec 2011 16:47:44 -0800 Message-ID: <20111214004744.28243.52925.stgit@elm3c44.beaverton.ibm.com> References: <20111214004613.28243.54122.stgit@elm3c44.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Sunil Mushran , Martin K Petersen , Greg Freemyer , Amir Goldstein , linux-kernel , Andi Kleen , Mingming Cao , Joel Becker , linux-fsdevel , linux-ext4@vger.kernel.org, Coly Li To: Andreas Dilger , Theodore Tso , "Darrick J. Wong" Return-path: Received: from e4.ny.us.ibm.com ([32.97.182.144]:43363 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756278Ab1LNAry (ORCPT ); Tue, 13 Dec 2011 19:47:54 -0500 Received: from /spool/local by e4.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 13 Dec 2011 19:47:53 -0500 In-Reply-To: <20111214004613.28243.54122.stgit@elm3c44.beaverton.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Add a new feature flag to enable block group descriptors to use the (faster) metadata_csum checksum algorithm. Signed-off-by: Darrick J. Wong --- fs/ext4/balloc.c | 2 +- fs/ext4/ext4.h | 4 ++- fs/ext4/ialloc.c | 11 ++++----- fs/ext4/mballoc.c | 6 ++--- fs/ext4/resize.c | 2 +- fs/ext4/super.c | 65 ++++++++++++++++++++++++++++++++++++++--------------- 6 files changed, 59 insertions(+), 31 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index dcac4bd..300f751 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -212,7 +212,7 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, sb->s_blocksize * 8, bh->b_data); ext4_block_bitmap_csum_set(sb, block_group, gdp, bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sbi, block_group, gdp); } /* Return the number of free blocks in a block group. It is used when diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index e7489c4..ae71af3 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2086,10 +2086,10 @@ extern void ext4_used_dirs_set(struct super_block *sb, struct ext4_group_desc *bg, __u32 count); extern void ext4_itable_unused_set(struct super_block *sb, struct ext4_group_desc *bg, __u32 count); -extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group, - struct ext4_group_desc *gdp); extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group, struct ext4_group_desc *gdp); +extern void ext4_group_desc_csum_set(struct ext4_sb_info *sbi, __u32 group, + struct ext4_group_desc *gdp); static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es) { diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 261ffce..6d33995 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -92,7 +92,7 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb, bh->b_data); ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh, EXT4_INODES_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sbi, block_group, gdp); return EXT4_INODES_PER_GROUP(sb); } @@ -287,7 +287,7 @@ void ext4_free_inode(handle_t *handle, struct inode *inode) } ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sbi, block_group, gdp); ext4_unlock_group(sb, block_group); percpu_counter_inc(&sbi->s_freeinodes_counter); @@ -697,7 +697,7 @@ static int ext4_claim_inode(struct super_block *sb, } ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); + ext4_group_desc_csum_set(sbi, group, gdp); err_ret: ext4_unlock_group(sb, group); up_read(&grp->alloc_sem); @@ -858,8 +858,7 @@ got: block_bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, - gdp); + ext4_group_desc_csum_set(sbi, group, gdp); } ext4_unlock_group(sb, group); @@ -1223,7 +1222,7 @@ int ext4_init_inode_table(struct super_block *sb, ext4_group_t group, skip_zeroout: ext4_lock_group(sb, group); gdp->bg_flags |= cpu_to_le16(EXT4_BG_INODE_ZEROED); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); + ext4_group_desc_csum_set(sbi, group, gdp); ext4_unlock_group(sb, group); BUFFER_TRACE(group_desc_bh, diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index dbd1453..2bbd9ee 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2919,7 +2919,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, ext4_free_group_clusters_set(sb, gdp, len); ext4_block_bitmap_csum_set(sb, ac->ac_b_ex.fe_group, gdp, bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, ac->ac_b_ex.fe_group, gdp); + ext4_group_desc_csum_set(sbi, ac->ac_b_ex.fe_group, gdp); ext4_unlock_group(sb, ac->ac_b_ex.fe_group); percpu_counter_sub(&sbi->s_freeclusters_counter, ac->ac_b_ex.fe_len); @@ -4787,7 +4787,7 @@ do_more: ext4_free_group_clusters_set(sb, gdp, ret); ext4_block_bitmap_csum_set(sb, block_group, gdp, bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sbi, block_group, gdp); ext4_unlock_group(sb, block_group); percpu_counter_add(&sbi->s_freeclusters_counter, count_clusters); @@ -4933,7 +4933,7 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb, ext4_free_group_clusters_set(sb, desc, blk_free_count); ext4_block_bitmap_csum_set(sb, block_group, desc, bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - desc->bg_checksum = ext4_group_desc_csum(sbi, block_group, desc); + ext4_group_desc_csum_set(sbi, block_group, desc); ext4_unlock_group(sb, block_group); percpu_counter_add(&sbi->s_freeclusters_counter, EXT4_B2C(sbi, blocks_freed)); diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index c33b72a..083f429 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -880,7 +880,7 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) ext4_free_group_clusters_set(sb, gdp, input->free_blocks_count); ext4_free_inodes_set(sb, gdp, EXT4_INODES_PER_GROUP(sb)); gdp->bg_flags = cpu_to_le16(EXT4_BG_INODE_ZEROED); - gdp->bg_checksum = ext4_group_desc_csum(sbi, input->group, gdp); + ext4_group_desc_csum_set(sbi, input->group, gdp); /* * We can allocate memory for mb_alloc based on the new group diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 5e2842c..6838d01 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2092,29 +2092,49 @@ failed: return 0; } -__le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group, - struct ext4_group_desc *gdp) +static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group, + struct ext4_group_desc *gdp) { + int offset; __u16 crc = 0; + __le32 le_group = cpu_to_le32(block_group); - if (sbi->s_es->s_feature_ro_compat & - cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { - int offset = offsetof(struct ext4_group_desc, bg_checksum); - __le32 le_group = cpu_to_le32(block_group); - - crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid)); - crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group)); - crc = crc16(crc, (__u8 *)gdp, offset); - offset += sizeof(gdp->bg_checksum); /* skip checksum */ - /* for checksum of struct ext4_group_desc do the rest...*/ - if ((sbi->s_es->s_feature_incompat & - cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) && - offset < le16_to_cpu(sbi->s_es->s_desc_size)) - crc = crc16(crc, (__u8 *)gdp + offset, - le16_to_cpu(sbi->s_es->s_desc_size) - - offset); + if ((sbi->s_es->s_feature_ro_compat & + cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) && + (sbi->s_es->s_feature_incompat & + cpu_to_le32(EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM))) { + /* Use new metadata_csum algorithm */ + __u16 old_csum; + __u32 csum32; + + old_csum = gdp->bg_checksum; + gdp->bg_checksum = 0; + csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group, + sizeof(le_group)); + csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, + sbi->s_desc_size); + gdp->bg_checksum = old_csum; + + crc = csum32 & 0xFFFF; + goto out; } + /* old crc16 code */ + offset = offsetof(struct ext4_group_desc, bg_checksum); + + crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid)); + crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group)); + crc = crc16(crc, (__u8 *)gdp, offset); + offset += sizeof(gdp->bg_checksum); /* skip checksum */ + /* for checksum of struct ext4_group_desc do the rest...*/ + if ((sbi->s_es->s_feature_incompat & + cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) && + offset < le16_to_cpu(sbi->s_es->s_desc_size)) + crc = crc16(crc, (__u8 *)gdp + offset, + le16_to_cpu(sbi->s_es->s_desc_size) - + offset); + +out: return cpu_to_le16(crc); } @@ -2129,6 +2149,15 @@ int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group, return 1; } +void ext4_group_desc_csum_set(struct ext4_sb_info *sbi, __u32 block_group, + struct ext4_group_desc *gdp) +{ + if (!(sbi->s_es->s_feature_ro_compat & + cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM))) + return; + gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); +} + /* Called at mount-time, super-block is locked */ static int ext4_check_descriptors(struct super_block *sb, ext4_group_t *first_not_zeroed)