From c7149d6bce2561aeaa48caaa1700aa8b3b22008f Mon Sep 17 00:00:00 2001 From: "Alan D. Brunelle" Date: Tue, 7 Aug 2007 15:30:23 +0200 Subject: [PATCH] Fix remap handling by blktrace This patch provides more information concerning REMAP operations on block IOs. The additional information provides clearer details at the user level, and supports post-processing analysis in btt. o Adds in partition remaps on the same device. o Fixed up the remap information in DM to be in the right order o Sent up mapped-from and mapped-to device information Signed-off-by: Alan D. Brunelle Signed-off-by: Jens Axboe --- block/ll_rw_blk.c | 4 ++++ drivers/md/dm.c | 4 ++-- include/linux/blktrace_api.h | 3 ++- 3 files changed, 8 insertions(+), 3 deletions(-) diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 8c2caff87cc3..a15845c164f2 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -3047,6 +3047,10 @@ static inline void blk_partition_remap(struct bio *bio) bio->bi_sector += p->start_sect; bio->bi_bdev = bdev->bd_contains; + + blk_add_trace_remap(bdev_get_queue(bio->bi_bdev), bio, + bdev->bd_dev, bio->bi_sector, + bio->bi_sector - p->start_sect); } } diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 141ff9fa296e..2120155929a6 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -580,8 +580,8 @@ static void __map_bio(struct dm_target *ti, struct bio *clone, /* the bio has been remapped so dispatch it */ blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone, - tio->io->bio->bi_bdev->bd_dev, sector, - clone->bi_sector); + tio->io->bio->bi_bdev->bd_dev, + clone->bi_sector, sector); generic_make_request(clone); } else if (r < 0 || r == DM_MAPIO_REQUEUE) { diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index 90874a5d7d78..7b5d56b82b59 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -105,7 +105,7 @@ struct blk_io_trace { */ struct blk_io_trace_remap { __be32 device; - u32 __pad; + __be32 device_from; __be64 sector; }; @@ -272,6 +272,7 @@ static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, return; r.device = cpu_to_be32(dev); + r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev); r.sector = cpu_to_be64(to); __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);