From 109e37653033a5fcd3bf8cab0ed6a7ff433f758a Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Fri, 18 Nov 2016 13:22:04 +1100 Subject: [PATCH] md: add block tracing for bio_remapping The block tracing infrastructure (accessed with blktrace/blkparse) supports the tracing of mapping bios from one device to another. This is currently used when a bio in a partition is mapped to the whole device, when bios are mapped by dm, and for mapping in md/raid5. Other md personalities do not include this tracing yet, so add it. When a read-error is detected we redirect the request to a different device. This could justifiably be seen as a new mapping for the originial bio, or a secondary mapping for the bio that errors. This patch uses the second option. When md is used under dm-raid, the mappings are not traced as we do not have access to the block device number of the parent. Signed-off-by: NeilBrown Signed-off-by: Shaohua Li --- drivers/md/linear.c | 18 ++++++++++++------ drivers/md/raid0.c | 13 ++++++++++--- drivers/md/raid1.c | 26 ++++++++++++++++++++++++-- drivers/md/raid10.c | 31 +++++++++++++++++++++++++++++-- 4 files changed, 75 insertions(+), 13 deletions(-) diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 9c7d4f5483ea..5975c9915684 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "md.h" #include "linear.h" @@ -227,22 +228,22 @@ static void linear_make_request(struct mddev *mddev, struct bio *bio) } do { - tmp_dev = which_dev(mddev, bio->bi_iter.bi_sector); + sector_t bio_sector = bio->bi_iter.bi_sector; + tmp_dev = which_dev(mddev, bio_sector); start_sector = tmp_dev->end_sector - tmp_dev->rdev->sectors; end_sector = tmp_dev->end_sector; data_offset = tmp_dev->rdev->data_offset; bio->bi_bdev = tmp_dev->rdev->bdev; - if (unlikely(bio->bi_iter.bi_sector >= end_sector || - bio->bi_iter.bi_sector < start_sector)) + if (unlikely(bio_sector >= end_sector || + bio_sector < start_sector)) goto out_of_bounds; if (unlikely(bio_end_sector(bio) > end_sector)) { /* This bio crosses a device boundary, so we have to * split it. */ - split = bio_split(bio, end_sector - - bio->bi_iter.bi_sector, + split = bio_split(bio, end_sector - bio_sector, GFP_NOIO, fs_bio_set); bio_chain(split, bio); } else { @@ -256,8 +257,13 @@ static void linear_make_request(struct mddev *mddev, struct bio *bio) !blk_queue_discard(bdev_get_queue(split->bi_bdev)))) { /* Just ignore it */ bio_endio(split); - } else + } else { + if (mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(split->bi_bdev), + split, disk_devt(mddev->gendisk), + bio_sector); generic_make_request(split); + } } while (split != bio); return; diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index b3ba77a3c3bc..e628f187e5ad 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "md.h" #include "raid0.h" #include "raid5.h" @@ -463,7 +464,8 @@ static void raid0_make_request(struct mddev *mddev, struct bio *bio) } do { - sector_t sector = bio->bi_iter.bi_sector; + sector_t bio_sector = bio->bi_iter.bi_sector; + sector_t sector = bio_sector; unsigned chunk_sects = mddev->chunk_sectors; unsigned sectors = chunk_sects - @@ -472,7 +474,7 @@ static void raid0_make_request(struct mddev *mddev, struct bio *bio) : sector_div(sector, chunk_sects)); /* Restore due to sector_div */ - sector = bio->bi_iter.bi_sector; + sector = bio_sector; if (sectors < bio_sectors(bio)) { split = bio_split(bio, sectors, GFP_NOIO, fs_bio_set); @@ -491,8 +493,13 @@ static void raid0_make_request(struct mddev *mddev, struct bio *bio) !blk_queue_discard(bdev_get_queue(split->bi_bdev)))) { /* Just ignore it */ bio_endio(split); - } else + } else { + if (mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(split->bi_bdev), + split, disk_devt(mddev->gendisk), + bio_sector); generic_make_request(split); + } } while (split != bio); } diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 9ac61cd85e5c..2dc1934925ec 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -37,6 +37,7 @@ #include #include #include +#include #include "md.h" #include "raid1.h" #include "bitmap.h" @@ -1162,6 +1163,11 @@ read_again: bio_set_op_attrs(read_bio, op, do_sync); read_bio->bi_private = r1_bio; + if (mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev), + read_bio, disk_devt(mddev->gendisk), + r1_bio->sector); + if (max_sectors < r1_bio->sectors) { /* could not read all from this device, so we will * need another r1_bio. @@ -1367,13 +1373,20 @@ read_again: mbio->bi_iter.bi_sector = (r1_bio->sector + conf->mirrors[i].rdev->data_offset); - mbio->bi_bdev = (void*)conf->mirrors[i].rdev; + mbio->bi_bdev = conf->mirrors[i].rdev->bdev; mbio->bi_end_io = raid1_end_write_request; bio_set_op_attrs(mbio, op, do_flush_fua | do_sync); mbio->bi_private = r1_bio; atomic_inc(&r1_bio->remaining); + if (mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(mbio->bi_bdev), + mbio, disk_devt(mddev->gendisk), + r1_bio->sector); + /* flush_pending_writes() needs access to the rdev so...*/ + mbio->bi_bdev = (void*)conf->mirrors[i].rdev; + cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug)); if (cb) plug = container_of(cb, struct raid1_plug_cb, cb); @@ -2290,6 +2303,8 @@ static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio) struct bio *bio; char b[BDEVNAME_SIZE]; struct md_rdev *rdev; + dev_t bio_dev; + sector_t bio_sector; clear_bit(R1BIO_ReadError, &r1_bio->state); /* we got a read error. Maybe the drive is bad. Maybe just @@ -2303,6 +2318,8 @@ static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio) bio = r1_bio->bios[r1_bio->read_disk]; bdevname(bio->bi_bdev, b); + bio_dev = bio->bi_bdev->bd_dev; + bio_sector = conf->mirrors[r1_bio->read_disk].rdev->data_offset + r1_bio->sector; bio_put(bio); r1_bio->bios[r1_bio->read_disk] = NULL; @@ -2353,6 +2370,8 @@ read_more: else mbio->bi_phys_segments++; spin_unlock_irq(&conf->device_lock); + trace_block_bio_remap(bdev_get_queue(bio->bi_bdev), + bio, bio_dev, bio_sector); generic_make_request(bio); bio = NULL; @@ -2367,8 +2386,11 @@ read_more: sectors_handled; goto read_more; - } else + } else { + trace_block_bio_remap(bdev_get_queue(bio->bi_bdev), + bio, bio_dev, bio_sector); generic_make_request(bio); + } } } diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 5290be3d5c26..67f0034d4956 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -25,6 +25,7 @@ #include #include #include +#include #include "md.h" #include "raid10.h" #include "raid0.h" @@ -1165,6 +1166,10 @@ read_again: bio_set_op_attrs(read_bio, op, do_sync); read_bio->bi_private = r10_bio; + if (mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev), + read_bio, disk_devt(mddev->gendisk), + r10_bio->sector); if (max_sectors < r10_bio->sectors) { /* Could not read all from this device, so we will * need another r10_bio. @@ -1367,11 +1372,18 @@ retry_write: mbio->bi_iter.bi_sector = (r10_bio->devs[i].addr+ choose_data_offset(r10_bio, rdev)); - mbio->bi_bdev = (void*)rdev; + mbio->bi_bdev = rdev->bdev; mbio->bi_end_io = raid10_end_write_request; bio_set_op_attrs(mbio, op, do_sync | do_fua); mbio->bi_private = r10_bio; + if (conf->mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(mbio->bi_bdev), + mbio, disk_devt(conf->mddev->gendisk), + r10_bio->sector); + /* flush_pending_writes() needs access to the rdev so...*/ + mbio->bi_bdev = (void*)rdev; + atomic_inc(&r10_bio->remaining); cb = blk_check_plugged(raid10_unplug, mddev, @@ -1409,11 +1421,18 @@ retry_write: mbio->bi_iter.bi_sector = (r10_bio->devs[i].addr + choose_data_offset( r10_bio, rdev)); - mbio->bi_bdev = (void*)rdev; + mbio->bi_bdev = rdev->bdev; mbio->bi_end_io = raid10_end_write_request; bio_set_op_attrs(mbio, op, do_sync | do_fua); mbio->bi_private = r10_bio; + if (conf->mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(mbio->bi_bdev), + mbio, disk_devt(conf->mddev->gendisk), + r10_bio->sector); + /* flush_pending_writes() needs access to the rdev so...*/ + mbio->bi_bdev = (void*)rdev; + atomic_inc(&r10_bio->remaining); spin_lock_irqsave(&conf->device_lock, flags); bio_list_add(&conf->pending_bio_list, mbio); @@ -2496,6 +2515,8 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio) char b[BDEVNAME_SIZE]; unsigned long do_sync; int max_sectors; + dev_t bio_dev; + sector_t bio_last_sector; /* we got a read error. Maybe the drive is bad. Maybe just * the block and we can fix it. @@ -2507,6 +2528,8 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio) */ bio = r10_bio->devs[slot].bio; bdevname(bio->bi_bdev, b); + bio_dev = bio->bi_bdev->bd_dev; + bio_last_sector = r10_bio->devs[slot].addr + rdev->data_offset + r10_bio->sectors; bio_put(bio); r10_bio->devs[slot].bio = NULL; @@ -2546,6 +2569,10 @@ read_more: bio_set_op_attrs(bio, REQ_OP_READ, do_sync); bio->bi_private = r10_bio; bio->bi_end_io = raid10_end_read_request; + trace_block_bio_remap(bdev_get_queue(bio->bi_bdev), + bio, bio_dev, + bio_last_sector - r10_bio->sectors); + if (max_sectors < r10_bio->sectors) { /* Drat - have to split this up more */ struct bio *mbio = r10_bio->master_bio; -- 2.39.5