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 <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 90874a5..7b5d56b 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -105,7 +105,7 @@
*/
struct blk_io_trace_remap {
__be32 device;
- u32 __pad;
+ __be32 device_from;
__be64 sector;
};
@@ -272,6 +272,7 @@
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);