From 4f024f3797c43cb4b73cd2c50cec728842d0e49e Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Fri, 11 Oct 2013 15:44:27 -0700 Subject: block: Abstract out bvec iterator MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: Geert Uytterhoeven Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: "Ed L. Cashin" Cc: Nick Piggin Cc: Lars Ellenberg Cc: Jiri Kosina Cc: Matthew Wilcox Cc: Geoff Levand Cc: Yehuda Sadeh Cc: Sage Weil Cc: Alex Elder Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris Cc: Philip Kelleher Cc: Rusty Russell Cc: "Michael S. Tsirkin" Cc: Konrad Rzeszutek Wilk Cc: Jeremy Fitzhardinge Cc: Neil Brown Cc: Alasdair Kergon Cc: Mike Snitzer Cc: dm-devel@redhat.com Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: linux390@de.ibm.com Cc: Boaz Harrosh Cc: Benny Halevy Cc: "James E.J. Bottomley" Cc: Greg Kroah-Hartman Cc: "Nicholas A. Bellinger" Cc: Alexander Viro Cc: Chris Mason Cc: "Theodore Ts'o" Cc: Andreas Dilger Cc: Jaegeuk Kim Cc: Steven Whitehouse Cc: Dave Kleikamp Cc: Joern Engel Cc: Prasad Joshi Cc: Trond Myklebust Cc: KONISHI Ryusuke Cc: Mark Fasheh Cc: Joel Becker Cc: Ben Myers Cc: xfs@oss.sgi.com Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Len Brown Cc: Pavel Machek Cc: "Rafael J. Wysocki" Cc: Herton Ronaldo Krzesinski Cc: Ben Hutchings Cc: Andrew Morton Cc: Guo Chao Cc: Tejun Heo Cc: Asai Thambi S P Cc: Selvan Mani Cc: Sam Bradshaw Cc: Wei Yongjun Cc: "Roger Pau Monné" Cc: Jan Beulich Cc: Stefano Stabellini Cc: Ian Campbell Cc: Sebastian Ott Cc: Christian Borntraeger Cc: Minchan Kim Cc: Jiang Liu Cc: Nitin Gupta Cc: Jerome Marchand Cc: Joe Perches Cc: Peng Tao Cc: Andy Adamson Cc: fanchaoting Cc: Jie Liu Cc: Sunil Mushran Cc: "Martin K. Petersen" Cc: Namjae Jeon Cc: Pankaj Kumar Cc: Dan Magenheimer Cc: Mel Gorman 6 --- drivers/md/dm-cache-target.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) (limited to 'drivers/md/dm-cache-target.c') diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 9efcf1059b99..86f9c83eb30c 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -664,15 +664,17 @@ static void remap_to_origin(struct cache *cache, struct bio *bio) static void remap_to_cache(struct cache *cache, struct bio *bio, dm_cblock_t cblock) { - sector_t bi_sector = bio->bi_sector; + sector_t bi_sector = bio->bi_iter.bi_sector; bio->bi_bdev = cache->cache_dev->bdev; if (!block_size_is_power_of_two(cache)) - bio->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_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) @@ -712,7 +714,7 @@ static void remap_to_cache_dirty(struct cache *cache, struct bio *bio, static dm_oblock_t get_bio_block(struct cache *cache, struct bio *bio) { - sector_t block_nr = bio->bi_sector; + sector_t block_nr = bio->bi_iter.bi_sector; if (!block_size_is_power_of_two(cache)) (void) sector_div(block_nr, cache->sectors_per_block); @@ -1027,7 +1029,7 @@ static void issue_overwrite(struct dm_cache_migration *mg, struct bio *bio) static bool bio_writes_complete_block(struct cache *cache, struct bio *bio) { return (bio_data_dir(bio) == WRITE) && - (bio->bi_size == (cache->sectors_per_block << SECTOR_SHIFT)); + (bio->bi_iter.bi_size == (cache->sectors_per_block << SECTOR_SHIFT)); } static void avoid_copy(struct dm_cache_migration *mg) @@ -1252,7 +1254,7 @@ static void process_flush_bio(struct cache *cache, struct bio *bio) size_t pb_data_size = get_per_bio_data_size(cache); struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); - BUG_ON(bio->bi_size); + BUG_ON(bio->bi_iter.bi_size); if (!pb->req_nr) remap_to_origin(cache, bio); else @@ -1275,9 +1277,9 @@ static void process_flush_bio(struct cache *cache, struct bio *bio) */ static void process_discard_bio(struct cache *cache, struct bio *bio) { - dm_block_t start_block = dm_sector_div_up(bio->bi_sector, + dm_block_t start_block = dm_sector_div_up(bio->bi_iter.bi_sector, cache->discard_block_size); - dm_block_t end_block = bio->bi_sector + bio_sectors(bio); + dm_block_t end_block = bio_end_sector(bio); dm_block_t b; end_block = block_div(end_block, cache->discard_block_size); -- cgit v1.2.3 From 196d38bccfcfa32faed8c561868336fdfa0fe8e4 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Sat, 23 Nov 2013 18:34:15 -0800 Subject: block: Generic bio chaining This adds a generic mechanism for chaining bio completions. This is going to be used for a bio_split() replacement, and it turns out to be very useful in a fair amount of driver code - a fair number of drivers were implementing this in their own roundabout ways, often painfully. Note that this means it's no longer to call bio_endio() more than once on the same bio! This can cause problems for drivers that save/restore bi_end_io. Arguably they shouldn't be saving/restoring bi_end_io at all - in all but the simplest cases they'd be better off just cloning the bio, and immutable biovecs is making bio cloning cheaper. But for now, we add a bio_endio_nodec() for these cases. Signed-off-by: Kent Overstreet Cc: Jens Axboe --- drivers/md/dm-cache-target.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/md/dm-cache-target.c') diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 86f9c83eb30c..bf3a206abd78 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -765,6 +765,12 @@ static void writethrough_endio(struct bio *bio, int err) dm_unhook_bio(&pb->hook_info, bio); + /* + * Must bump bi_remaining to allow bio to complete with + * restored bi_end_io. + */ + atomic_inc(&bio->bi_remaining); + if (err) { bio_endio(bio, err); return; -- cgit v1.2.3 From 8d30726912cb39c3a3ebde06214d54861f8fdde2 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Tue, 3 Dec 2013 19:16:04 -0700 Subject: dm cache: increment bi_remaining when bi_end_io is restored Move the bio->bi_remaining increment into dm_unhook_bio() so the overwrite_endio() handler works as expected. Signed-off-by: Mike Snitzer Signed-off-by: Jens Axboe --- drivers/md/dm-cache-target.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/md/dm-cache-target.c') diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index bf3a206abd78..7c8dd1f69ce0 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -85,6 +85,12 @@ static void dm_unhook_bio(struct dm_hook_info *h, struct bio *bio) { bio->bi_end_io = h->bi_end_io; bio->bi_private = h->bi_private; + + /* + * Must bump bi_remaining to allow bio to complete with + * restored bi_end_io. + */ + atomic_inc(&bio->bi_remaining); } /*----------------------------------------------------------------*/ @@ -765,12 +771,6 @@ static void writethrough_endio(struct bio *bio, int err) dm_unhook_bio(&pb->hook_info, bio); - /* - * Must bump bi_remaining to allow bio to complete with - * restored bi_end_io. - */ - atomic_inc(&bio->bi_remaining); - if (err) { bio_endio(bio, err); return; -- cgit v1.2.3 From 6a388618f120cdc70cd6b6dbcab5f7a4aff500f6 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Thu, 9 Jan 2014 16:04:12 -0500 Subject: dm cache: add block sizes and total cache blocks to status output Improve cache_status to emit: <#used metadata blocks>/<#total metadata blocks> <#used cache blocks>/<#total cache blocks> ... Adding the block sizes allows for easier calculation of the overall size of both the metadata and cache devices. Adding <#total cache blocks> provides useful context for how much of the cache is used. Unfortunately these additions to the status will require updates to users' scripts that monitor the cache status. But these changes help provide more comprehensive information about the cache device and will simplify tools that are being developed to manage dm-cache devices -- because they won't need to issue 3 operations to cobble together the information that we can easily provide via a single status ioctl. While updating the status documentation in cache.txt spaces were tabify'd. Requested-by: Jonathan Brassow Signed-off-by: Mike Snitzer Acked-by: Joe Thornber --- drivers/md/dm-cache-target.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'drivers/md/dm-cache-target.c') diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 1b1469ebe5cb..11ad70540d40 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -2826,9 +2826,10 @@ static void cache_resume(struct dm_target *ti) /* * Status format: * - * <#used metadata blocks>/<#total metadata blocks> + * <#used metadata blocks>/<#total metadata blocks> + * <#used cache blocks>/<#total cache blocks> * <#read hits> <#read misses> <#write hits> <#write misses> - * <#demotions> <#promotions> <#blocks in cache> <#dirty> + * <#demotions> <#promotions> <#dirty> * <#features> * * <#core args> * <#policy args> * @@ -2869,17 +2870,20 @@ static void cache_status(struct dm_target *ti, status_type_t type, residency = policy_residency(cache->policy); - DMEMIT("%llu/%llu %u %u %u %u %u %u %llu %u ", + DMEMIT("%u %llu/%llu %u %llu/%llu %u %u %u %u %u %u %llu ", + (unsigned)(DM_CACHE_METADATA_BLOCK_SIZE >> SECTOR_SHIFT), (unsigned long long)(nr_blocks_metadata - nr_free_blocks_metadata), (unsigned long long)nr_blocks_metadata, + cache->sectors_per_block, + (unsigned long long) from_cblock(residency), + (unsigned long long) from_cblock(cache->cache_size), (unsigned) atomic_read(&cache->stats.read_hit), (unsigned) atomic_read(&cache->stats.read_miss), (unsigned) atomic_read(&cache->stats.write_hit), (unsigned) atomic_read(&cache->stats.write_miss), (unsigned) atomic_read(&cache->stats.demotion), (unsigned) atomic_read(&cache->stats.promotion), - (unsigned long long) from_cblock(residency), - cache->nr_dirty); + (unsigned long long) from_cblock(cache->nr_dirty)); if (writethrough_mode(&cache->features)) DMEMIT("1 writethrough "); @@ -3129,7 +3133,7 @@ static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits) static struct target_type cache_target = { .name = "cache", - .version = {1, 2, 0}, + .version = {1, 3, 0}, .module = THIS_MODULE, .ctr = cache_ctr, .dtr = cache_dtr, -- cgit v1.2.3 From 2e68c4e6caad9fdadc1cef8b6cb9569192e8a42b Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Wed, 15 Jan 2014 21:06:55 -0500 Subject: dm cache: add policy name to status output The cache's policy may have been established using the "default" alias, which is currently the "mq" policy but the default policy may change in the future. It is useful to know exactly which policy is being used. Add a 'real' member to the dm_cache_policy_type structure and have the "default" dm_cache_policy_type point to the real "mq" dm_cache_policy_type. Update dm_cache_policy_get_name() to check if real is set, if so report the name of the real policy (not the alias). Requested-by: Jonathan Brassow Signed-off-by: Mike Snitzer --- drivers/md/dm-cache-target.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/md/dm-cache-target.c') diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 11ad70540d40..09334c275c79 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -2832,7 +2832,7 @@ static void cache_resume(struct dm_target *ti) * <#demotions> <#promotions> <#dirty> * <#features> * * <#core args> - * <#policy args> * + * <#policy args> * */ static void cache_status(struct dm_target *ti, status_type_t type, unsigned status_flags, char *result, unsigned maxlen) @@ -2900,6 +2900,8 @@ static void cache_status(struct dm_target *ti, status_type_t type, } DMEMIT("2 migration_threshold %llu ", (unsigned long long) cache->migration_threshold); + + DMEMIT("%s ", dm_cache_policy_get_name(cache->policy)); if (sz < maxlen) { r = policy_emit_config_values(cache->policy, result + sz, maxlen - sz); if (r) -- cgit v1.2.3