From a48f041d91bf1aee599fa2adb53b780ed20c2ee5 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Wed, 21 Oct 2015 13:19:38 -0400 Subject: [PATCH] block: Reduce the size of struct blk_integrity The per-device properties in the blk_integrity structure were previously unsigned short. However, most of the values fit inside a char. The only exception is the data interval size and we can work around that by storing it as a power of two. This cuts the size of the dynamic portion of blk_integrity in half. Signed-off-by: Martin K. Petersen Reported-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Dan Williams Signed-off-by: Jens Axboe --- block/bio-integrity.c | 4 ++-- block/blk-integrity.c | 6 +++--- include/linux/blkdev.h | 8 ++++---- 3 files changed, 9 insertions(+), 9 deletions(-) diff --git a/block/bio-integrity.c b/block/bio-integrity.c index a10ffe19a8dd..6a90eca9cea1 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -202,7 +202,7 @@ EXPORT_SYMBOL(bio_integrity_enabled); static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi, unsigned int sectors) { - return sectors >> (ilog2(bi->interval) - 9); + return sectors >> (bi->interval_exp - 9); } static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi, @@ -229,7 +229,7 @@ static int bio_integrity_process(struct bio *bio, bip->bip_vec->bv_offset; iter.disk_name = bio->bi_bdev->bd_disk->disk_name; - iter.interval = bi->interval; + iter.interval = 1 << bi->interval_exp; iter.seed = bip_get_seed(bip); iter.prot_buf = prot_buf; diff --git a/block/blk-integrity.c b/block/blk-integrity.c index daf590ab3b46..c7508654faff 100644 --- a/block/blk-integrity.c +++ b/block/blk-integrity.c @@ -155,10 +155,10 @@ int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2) if (!b1 || !b2) return -1; - if (b1->interval != b2->interval) { + if (b1->interval_exp != b2->interval_exp) { pr_err("%s: %s/%s protection interval %u != %u\n", __func__, gd1->disk_name, gd2->disk_name, - b1->interval, b2->interval); + 1 << b1->interval_exp, 1 << b2->interval_exp); return -1; } @@ -440,7 +440,7 @@ int blk_integrity_register(struct gendisk *disk, struct blk_integrity *template) kobject_uevent(&disk->integrity_kobj, KOBJ_ADD); bi->flags |= BLK_INTEGRITY_VERIFY | BLK_INTEGRITY_GENERATE; - bi->interval = queue_logical_block_size(disk->queue); + bi->interval_exp = ilog2(queue_logical_block_size(disk->queue)); disk->integrity = bi; } else bi = disk->integrity; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index f36c6476f1c7..4f1968f15e30 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1470,10 +1470,10 @@ struct blk_integrity_profile { struct blk_integrity { struct blk_integrity_profile *profile; - unsigned short flags; - unsigned short tuple_size; - unsigned short interval; - unsigned short tag_size; + unsigned char flags; + unsigned char tuple_size; + unsigned char interval_exp; + unsigned char tag_size; }; extern bool blk_integrity_is_initialized(struct gendisk *); -- 2.20.1