On Fri, Oct 11 2013 at 12:13am -0400, Kent Overstreet <kmo@xxxxxxxxxxxxx> wrote: > On Sun, Oct 06, 2013 at 08:14:10PM -0400, Mike Snitzer wrote: > > > > Please fold this fix into your for-jens branch, thanks. (Could be that > > by the time Jens takes your immutable biovec changes we'll need to > > rebase but at least it won't slip through the cracks). > > Thanks! I knew that bio chaining patch was going to cause a few issues > like this, but it seems to useful to pass up. Anything else come up/any > comments? I'm wondering if there might be a cleaner way to hide the quirky nature of the bio chaining with saved/restored bi_end_io. Joe Thornber implemented utility wrappers local to dm-cache, see: http://people.redhat.com/msnitzer/patches/upstream/dm-cache-for-v3.13/dm-cache-utils-for-hooking-bios.patch would be natural to elevate something like this to the block layer and then bury the quirk of needing to bump bi_remaining when the bi_end_io is restored in unhook_bio(). Aside from that idea, your immutable biovec changes look sane to me. I like how much was able to be removed from DM core. I don't see any remaining problems that stand out. Feel free to add the following to your DM patches in the series: Reviewed-by: Mike Snitzer <snitzer@xxxxxxxxxx> However, I did collect various style nits in the DM code during my review. I'd like to see these changes applied: Author: Mike Snitzer <snitzer@xxxxxxxxxx> Date: Fri Sep 27 18:14:38 2013 -0400 dm: style nits and comment for immutable biovec changes --- drivers/md/dm-cache-target.c | 16 ++++++++++------ drivers/md/dm-crypt.c | 8 ++------ drivers/md/dm-io.c | 3 +-- drivers/md/dm-snap.c | 8 ++++---- drivers/md/dm-thin.c | 3 +-- drivers/md/dm-verity.c | 3 +-- drivers/md/dm.c | 6 ++---- include/linux/dm-io.h | 2 +- 8 files changed, 22 insertions(+), 27 deletions(-) diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index a9acec6..1ccbfff 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -571,13 +571,13 @@ static void remap_to_cache(struct cache *cache, struct bio *bio, bio->bi_bdev = cache->cache_dev->bdev; if (!block_size_is_power_of_two(cache)) - bio->bi_iter.bi_sector = (from_cblock(cblock) * - cache->sectors_per_block) + - sector_div(bi_sector, cache->sectors_per_block); + bio->bi_iter.bi_sector = + (from_cblock(cblock) * cache->sectors_per_block) + + sector_div(bi_sector, cache->sectors_per_block); else - bio->bi_iter.bi_sector = (from_cblock(cblock) << - cache->sectors_per_block_shift) | - (bi_sector & (cache->sectors_per_block - 1)); + bio->bi_iter.bi_sector = + (from_cblock(cblock) << cache->sectors_per_block_shift) | + (bi_sector & (cache->sectors_per_block - 1)); } static void check_if_tick_bio_needed(struct cache *cache, struct bio *bio) @@ -666,6 +666,10 @@ static void writethrough_endio(struct bio *bio, int err) struct per_bio_data *pb = get_per_bio_data(bio, PB_DATA_SIZE_WT); bio->bi_end_io = pb->saved_bi_end_io; + /* + * Must bump bi_remaining to allow bio to complete with + * restored bi_end_io. + */ atomic_inc(&bio->bi_remaining); if (err) { diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index e0b902f..4db7e48 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -648,12 +648,10 @@ static void crypt_convert_init(struct crypt_config *cc, { ctx->bio_in = bio_in; ctx->bio_out = bio_out; - if (bio_in) ctx->iter_in = bio_in->bi_iter; if (bio_out) ctx->iter_out = bio_out->bi_iter; - ctx->cc_sector = sector + cc->iv_offset; init_completion(&ctx->restart); } @@ -752,8 +750,7 @@ static int crypt_convert(struct crypt_config *cc, atomic_set(&ctx->cc_pending, 1); - while (ctx->iter_in.bi_size && - ctx->iter_out.bi_size) { + while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { crypt_alloc_req(cc, ctx); @@ -1676,8 +1673,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio) return DM_MAPIO_REMAPPED; } - io = crypt_io_alloc(cc, bio, - dm_target_offset(ti, bio->bi_iter.bi_sector)); + io = crypt_io_alloc(cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); if (bio_data_dir(io->base_bio) == READ) { if (kcryptd_io_read(io, GFP_NOWAIT)) diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c index 9cc1f3a..b2b8a10 100644 --- a/drivers/md/dm-io.c +++ b/drivers/md/dm-io.c @@ -307,8 +307,7 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where, dm_sector_div_up(remaining, (PAGE_SIZE >> SECTOR_SHIFT))); bio = bio_alloc_bioset(GFP_NOIO, num_bvecs, io->client->bios); - bio->bi_iter.bi_sector = where->sector + - (where->count - remaining); + bio->bi_iter.bi_sector = where->sector + (where->count - remaining); bio->bi_bdev = where->bdev; bio->bi_end_io = endio; store_io_and_region_in_bio(bio, io, region); diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 2e55bda..b7a5053 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -1563,10 +1563,10 @@ static void remap_exception(struct dm_snapshot *s, struct dm_exception *e, { bio->bi_bdev = s->cow->bdev; bio->bi_iter.bi_sector = chunk_to_sector(s->store, - dm_chunk_number(e->new_chunk) + - (chunk - e->old_chunk)) + - (bio->bi_iter.bi_sector & - s->store->chunk_mask); + dm_chunk_number(e->new_chunk) + + (chunk - e->old_chunk)) + + (bio->bi_iter.bi_sector & + s->store->chunk_mask); } static int snapshot_map(struct dm_target *ti, struct bio *bio) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 6742927..a654024 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -1255,8 +1255,7 @@ static void process_bio_read_only(struct thin_c *tc, struct bio *bio) r = dm_thin_find_block(tc->td, block, 1, &lookup_result); switch (r) { case 0: - if (lookup_result.shared && - (rw == WRITE) && bio->bi_iter.bi_size) + if (lookup_result.shared && (rw == WRITE) && bio->bi_iter.bi_size) bio_io_error(bio); else { inc_all_io_entry(tc->pool, bio); diff --git a/drivers/md/dm-verity.c b/drivers/md/dm-verity.c index 64d829a..ac35e95 100644 --- a/drivers/md/dm-verity.c +++ b/drivers/md/dm-verity.c @@ -496,8 +496,7 @@ static int verity_map(struct dm_target *ti, struct bio *bio) io->v = v; io->orig_bi_end_io = bio->bi_end_io; io->orig_bi_private = bio->bi_private; - io->block = bio->bi_iter.bi_sector >> - (v->data_dev_block_bits - SECTOR_SHIFT); + io->block = bio->bi_iter.bi_sector >> (v->data_dev_block_bits - SECTOR_SHIFT); io->n_blocks = bio->bi_iter.bi_size >> v->data_dev_block_bits; bio->bi_end_io = verity_end_io; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index a396137..5846801 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -539,8 +539,7 @@ static void start_io_acct(struct dm_io *io) atomic_inc_return(&md->pending[rw])); if (unlikely(dm_stats_used(&md->stats))) - dm_stats_account_io(&md->stats, bio->bi_rw, - bio->bi_iter.bi_sector, + dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, bio_sectors(bio), false, 0, &io->stats_aux); } @@ -558,8 +557,7 @@ static void end_io_acct(struct dm_io *io) part_stat_unlock(); if (unlikely(dm_stats_used(&md->stats))) - dm_stats_account_io(&md->stats, bio->bi_rw, - bio->bi_iter.bi_sector, + dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector, bio_sectors(bio), true, duration, &io->stats_aux); /* diff --git a/include/linux/dm-io.h b/include/linux/dm-io.h index 6cf1f62..a68cbe5 100644 --- a/include/linux/dm-io.h +++ b/include/linux/dm-io.h @@ -29,7 +29,7 @@ typedef void (*io_notify_fn)(unsigned long error, void *context); enum dm_io_mem_type { DM_IO_PAGE_LIST,/* Page list */ - DM_IO_BIO, + DM_IO_BIO, /* Bio vector */ DM_IO_VMA, /* Virtual memory area */ DM_IO_KMEM, /* Kernel memory */ }; -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
