Commit Graph

770 Commits

Author SHA1 Message Date
Lin Feng 0259d4498b bcache: move calc_cached_dev_sectors to proper place on backing device detach
Calculation of cache_set's cached sectors is done by travelling
cached_devs list as shown below:

static void calc_cached_dev_sectors(struct cache_set *c)
{
...
        list_for_each_entry(dc, &c->cached_devs, list)
                sectors += bdev_sectors(dc->bdev);

        c->cached_dev_sectors = sectors;
}

But cached_dev won't be unlinked from c->cached_devs list until we call
following list_move(&dc->list, &uncached_devices),
so previous fix in 'commit 46010141da
("bcache: recal cached_dev_sectors on detach")' is wrong, now we move
it to its right place.

Signed-off-by: Lin Feng <linf@wangsu.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-5-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Chao Yu d55f7cb2e5 bcache: fix error info in register_bcache()
In register_bcache(), there are several cases we didn't set
correct error info (return value and/or error message):
- if kzalloc() fails, it needs to return ENOMEM and print
"cannot allocate memory";
- if register_cache() fails, it's better to propagate its
return value rather than using default EINVAL.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-4-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Ding Senjie a307e2abfc md: bcache: Fix spelling of 'acquire'
acqurie -> acquire

Signed-off-by: Ding Senjie <dingsenjie@yulong.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-2-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Christoph Hellwig cda25b82c4 bcache: remove bdev_sectors
Use the equivalent block layer helper instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Acked-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211018101130.1838532-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:43:22 -06:00
Christoph Hellwig 3e08773c38 block: switch polling to be bio based
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.

Polling for the bio itself leads to a few advantages:

 - the cookie construction can made entirely private in blk-mq.c
 - the caller does not need to remember the request_queue and cookie
   separately and thus sidesteps their lifetime issues
 - keeping the device and the cookie inside the bio allows to trivially
   support polling BIOs remapping by stacking drivers
 - a lot of code to propagate the cookie back up the submission path can
   be removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:36 -06:00
Christoph Hellwig 2fd3e5efe7 bcache: use bvec_virt
Use bvec_virt instead of open coding it.  Note that the existing code is
fine despite ignoring bv_offset as the bio is known to contain exactly
one page from the page allocator per bio_vec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210804095634.460779-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-16 10:50:33 -06:00
Christoph Hellwig b75f4aed88 bcache: move the del_gendisk call out of bcache_device_free
Let the callers call del_gendisk so that we can check if add_disk
has been called properly for the cached device case instead of relying
on the block layer internal GENHD_FL_UP flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210809064028.1198327-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-12 10:29:36 -06:00
Christoph Hellwig 224b068322 bcache: add proper error unwinding in bcache_device_init
Except for the IDA none of the allocations in bcache_device_init is
unwound on error, fix that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210809064028.1198327-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-12 10:29:36 -06:00
Guoqing Jiang 018eca456c block: move some macros to blkdev.h
Move them (PAGE_SECTORS_SHIFT, PAGE_SECTORS and SECTOR_MASK) to the
generic header file to remove redundancy.

Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Link: https://lore.kernel.org/r/20210721025315.1729118-1-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-11 19:40:28 -06:00
Christoph Hellwig c66fd01971 block: make the block holder code optional
Move the block holder code into a separate file as it is not in any way
related to the other block_dev.c code, and add a new selectable config
option for it so that we don't have to build it without any remapped
drivers selected.

The Kconfig symbol contains a _DEPRECATED suffix to match the comments
added in commit 49731baa41
("block: restore multiple bd_link_disk_holder() support").

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20210804094147.459763-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-09 11:50:42 -06:00
Linus Torvalds df668a5fe4 for-5.14/block-2021-06-29
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Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block

Pull core block updates from Jens Axboe:

 - disk events cleanup (Christoph)

 - gendisk and request queue allocation simplifications (Christoph)

 - bdev_disk_changed cleanups (Christoph)

 - IO priority improvements (Bart)

 - Chained bio completion trace fix (Edward)

 - blk-wbt fixes (Jan)

 - blk-wbt enable/disable fix (Zhang)

 - Scheduler dispatch improvements (Jan, Ming)

 - Shared tagset scheduler improvements (John)

 - BFQ updates (Paolo, Luca, Pietro)

 - BFQ lock inversion fix (Jan)

 - Documentation improvements (Kir)

 - CLONE_IO block cgroup fix (Tejun)

 - Remove of ancient and deprecated block dump feature (zhangyi)

 - Discard merge fix (Ming)

 - Misc fixes or followup fixes (Colin, Damien, Dan, Long, Max, Thomas,
   Yang)

* tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block: (129 commits)
  block: fix discard request merge
  block/mq-deadline: Remove a WARN_ON_ONCE() call
  blk-mq: update hctx->dispatch_busy in case of real scheduler
  blk: Fix lock inversion between ioc lock and bfqd lock
  bfq: Remove merged request already in bfq_requests_merged()
  block: pass a gendisk to bdev_disk_changed
  block: move bdev_disk_changed
  block: add the events* attributes to disk_attrs
  block: move the disk events code to a separate file
  block: fix trace completion for chained bio
  block/partitions/msdos: Fix typo inidicator -> indicator
  block, bfq: reset waker pointer with shared queues
  block, bfq: check waker only for queues with no in-flight I/O
  block, bfq: avoid delayed merge of async queues
  block, bfq: boost throughput by extending queue-merging times
  block, bfq: consider also creation time in delayed stable merge
  block, bfq: fix delayed stable merge check
  block, bfq: let also stably merged queues enjoy weight raising
  blk-wbt: make sure throttle is enabled properly
  blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled()
  ...
2021-06-30 12:12:56 -07:00
Linus Torvalds efc1fd601a block-5.13-2021-06-12
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Merge tag 'block-5.13-2021-06-12' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A few fixes that should go into 5.13:

   - Fix a regression deadlock introduced in this release between open
     and remove of a bdev (Christoph)

   - Fix an async_xor md regression in this release (Xiao)

   - Fix bcache oversized read issue (Coly)"

* tag 'block-5.13-2021-06-12' of git://git.kernel.dk/linux-block:
  block: loop: fix deadlock between open and remove
  async_xor: check src_offs is not NULL before updating it
  bcache: avoid oversized read request in cache missing code path
  bcache: remove bcache device self-defined readahead
2021-06-12 11:59:58 -07:00
Coly Li 41fe8d088e bcache: avoid oversized read request in cache missing code path
In the cache missing code path of cached device, if a proper location
from the internal B+ tree is matched for a cache miss range, function
cached_dev_cache_miss() will be called in cache_lookup_fn() in the
following code block,
[code block 1]
  526         unsigned int sectors = KEY_INODE(k) == s->iop.inode
  527                 ? min_t(uint64_t, INT_MAX,
  528                         KEY_START(k) - bio->bi_iter.bi_sector)
  529                 : INT_MAX;
  530         int ret = s->d->cache_miss(b, s, bio, sectors);

Here s->d->cache_miss() is the call backfunction pointer initialized as
cached_dev_cache_miss(), the last parameter 'sectors' is an important
hint to calculate the size of read request to backing device of the
missing cache data.

Current calculation in above code block may generate oversized value of
'sectors', which consequently may trigger 2 different potential kernel
panics by BUG() or BUG_ON() as listed below,

1) BUG_ON() inside bch_btree_insert_key(),
[code block 2]
   886         BUG_ON(b->ops->is_extents && !KEY_SIZE(k));
2) BUG() inside biovec_slab(),
[code block 3]
   51         default:
   52                 BUG();
   53                 return NULL;

All the above panics are original from cached_dev_cache_miss() by the
oversized parameter 'sectors'.

Inside cached_dev_cache_miss(), parameter 'sectors' is used to calculate
the size of data read from backing device for the cache missing. This
size is stored in s->insert_bio_sectors by the following lines of code,
[code block 4]
  909    s->insert_bio_sectors = min(sectors, bio_sectors(bio) + reada);

Then the actual key inserting to the internal B+ tree is generated and
stored in s->iop.replace_key by the following lines of code,
[code block 5]
  911   s->iop.replace_key = KEY(s->iop.inode,
  912                    bio->bi_iter.bi_sector + s->insert_bio_sectors,
  913                    s->insert_bio_sectors);
The oversized parameter 'sectors' may trigger panic 1) by BUG_ON() from
the above code block.

And the bio sending to backing device for the missing data is allocated
with hint from s->insert_bio_sectors by the following lines of code,
[code block 6]
  926    cache_bio = bio_alloc_bioset(GFP_NOWAIT,
  927                 DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS),
  928                 &dc->disk.bio_split);
The oversized parameter 'sectors' may trigger panic 2) by BUG() from the
agove code block.

Now let me explain how the panics happen with the oversized 'sectors'.
In code block 5, replace_key is generated by macro KEY(). From the
definition of macro KEY(),
[code block 7]
  71 #define KEY(inode, offset, size)                                  \
  72 ((struct bkey) {                                                  \
  73      .high = (1ULL << 63) | ((__u64) (size) << 20) | (inode),     \
  74      .low = (offset)                                              \
  75 })

Here 'size' is 16bits width embedded in 64bits member 'high' of struct
bkey. But in code block 1, if "KEY_START(k) - bio->bi_iter.bi_sector" is
very probably to be larger than (1<<16) - 1, which makes the bkey size
calculation in code block 5 is overflowed. In one bug report the value
of parameter 'sectors' is 131072 (= 1 << 17), the overflowed 'sectors'
results the overflowed s->insert_bio_sectors in code block 4, then makes
size field of s->iop.replace_key to be 0 in code block 5. Then the 0-
sized s->iop.replace_key is inserted into the internal B+ tree as cache
missing check key (a special key to detect and avoid a racing between
normal write request and cache missing read request) as,
[code block 8]
  915   ret = bch_btree_insert_check_key(b, &s->op, &s->iop.replace_key);

Then the 0-sized s->iop.replace_key as 3rd parameter triggers the bkey
size check BUG_ON() in code block 2, and causes the kernel panic 1).

Another kernel panic is from code block 6, is by the bvecs number
oversized value s->insert_bio_sectors from code block 4,
        min(sectors, bio_sectors(bio) + reada)
There are two possibility for oversized reresult,
- bio_sectors(bio) is valid, but bio_sectors(bio) + reada is oversized.
- sectors < bio_sectors(bio) + reada, but sectors is oversized.

From a bug report the result of "DIV_ROUND_UP(s->insert_bio_sectors,
PAGE_SECTORS)" from code block 6 can be 344, 282, 946, 342 and many
other values which larther than BIO_MAX_VECS (a.k.a 256). When calling
bio_alloc_bioset() with such larger-than-256 value as the 2nd parameter,
this value will eventually be sent to biovec_slab() as parameter
'nr_vecs' in following code path,
   bio_alloc_bioset() ==> bvec_alloc() ==> biovec_slab()
Because parameter 'nr_vecs' is larger-than-256 value, the panic by BUG()
in code block 3 is triggered inside biovec_slab().

From the above analysis, we know that the 4th parameter 'sector' sent
into cached_dev_cache_miss() may cause overflow in code block 5 and 6,
and finally cause kernel panic in code block 2 and 3. And if result of
bio_sectors(bio) + reada exceeds valid bvecs number, it may also trigger
kernel panic in code block 3 from code block 6.

Now the almost-useless readahead size for cache missing request back to
backing device is removed, this patch can fix the oversized issue with
more simpler method.
- add a local variable size_limit,  set it by the minimum value from
  the max bkey size and max bio bvecs number.
- set s->insert_bio_sectors by the minimum value from size_limit,
  sectors, and the sectors size of bio.
- replace sectors by s->insert_bio_sectors to do bio_next_split.

By the above method with size_limit, s->insert_bio_sectors will never
result oversized replace_key size or bio bvecs number. And split bio
'miss' from bio_next_split() will always match the size of 'cache_bio',
that is the current maximum bio size we can sent to backing device for
fetching the cache missing data.

Current problmatic code can be partially found since Linux v3.13-rc1,
therefore all maintained stable kernels should try to apply this fix.

Reported-by: Alexander Ullrich <ealex1979@gmail.com>
Reported-by: Diego Ercolani <diego.ercolani@gmail.com>
Reported-by: Jan Szubiak <jan.szubiak@linuxpolska.pl>
Reported-by: Marco Rebhan <me@dblsaiko.net>
Reported-by: Matthias Ferdinand <bcache@mfedv.net>
Reported-by: Victor Westerhuis <victor@westerhu.is>
Reported-by: Vojtech Pavlik <vojtech@suse.cz>
Reported-and-tested-by: Rolf Fokkens <rolf@rolffokkens.nl>
Reported-and-tested-by: Thorsten Knabe <linux@thorsten-knabe.de>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Nix <nix@esperi.org.uk>
Cc: Takashi Iwai <tiwai@suse.com>
Link: https://lore.kernel.org/r/20210607125052.21277-3-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-08 15:06:03 -06:00
Coly Li 1616a4c2ab bcache: remove bcache device self-defined readahead
For read cache missing, bcache defines a readahead size for the read I/O
request to the backing device for the missing data. This readahead size
is initialized to 0, and almost no one uses it to avoid unnecessary read
amplifying onto backing device and write amplifying onto cache device.
Considering upper layer file system code has readahead logic allready
and works fine with readahead_cache_policy sysfile interface, we don't
have to keep bcache self-defined readahead anymore.

This patch removes the bcache self-defined readahead for cache missing
request for backing device, and the readahead sysfs file interfaces are
removed as well.

This is the preparation for next patch to fix potential kernel panic due
to oversized request in a simpler method.

Reported-by: Alexander Ullrich <ealex1979@gmail.com>
Reported-by: Diego Ercolani <diego.ercolani@gmail.com>
Reported-by: Jan Szubiak <jan.szubiak@linuxpolska.pl>
Reported-by: Marco Rebhan <me@dblsaiko.net>
Reported-by: Matthias Ferdinand <bcache@mfedv.net>
Reported-by: Victor Westerhuis <victor@westerhu.is>
Reported-by: Vojtech Pavlik <vojtech@suse.cz>
Reported-and-tested-by: Rolf Fokkens <rolf@rolffokkens.nl>
Reported-and-tested-by: Thorsten Knabe <linux@thorsten-knabe.de>
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Nix <nix@esperi.org.uk>
Cc: Takashi Iwai <tiwai@suse.com>
Link: https://lore.kernel.org/r/20210607125052.21277-2-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-08 15:06:03 -06:00
Christoph Hellwig bc70852fd1 bcache: convert to blk_alloc_disk/blk_cleanup_disk
Convert the bcache driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01 07:42:23 -06:00
Matthew Wilcox (Oracle) 4ee60ec156 include: remove pagemap.h from blkdev.h
My UEK-derived config has 1030 files depending on pagemap.h before this
change.  Afterwards, just 326 files need to be rebuilt when I touch
pagemap.h.  I think blkdev.h is probably included too widely, but
untangling that dependency is harder and this solves my problem.  x86
allmodconfig builds, but there may be implicit include problems on other
architectures.

Link: https://lkml.kernel.org/r/20210309195747.283796-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>		[nvdimm]
Acked-by: Jens Axboe <axboe@kernel.dk>				[block]
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Coly Li <colyli@suse.de>				[bcache]
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>	[scsi]
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06 19:24:11 -07:00
Coly Li 33ec5dfe8f bcache: fix a regression of code compiling failure in debug.c
The patch "bcache: remove PTR_CACHE" introduces a compiling failure in
debug.c with following error message,
  In file included from drivers/md/bcache/bcache.h:182:0,
                   from drivers/md/bcache/debug.c:9:
  drivers/md/bcache/debug.c: In function 'bch_btree_verify':
  drivers/md/bcache/debug.c:53:19: error: 'c' undeclared (first use in
  this function)
    bio_set_dev(bio, c->cache->bdev);
                     ^
This patch fixes the regression by replacing c->cache->bdev by b->c->
cache->bdev.

Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210411134316.80274-8-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-11 08:37:56 -06:00
Gustavo A. R. Silva 62594f189e bcache: Use 64-bit arithmetic instead of 32-bit
Cast multiple variables to (int64_t) in order to give the compiler
complete information about the proper arithmetic to use. Notice that
these variables are being used in contexts that expect expressions of
type int64_t  (64 bit, signed). And currently, such expressions are
being evaluated using 32-bit arithmetic.

Fixes: d0cf9503e9 ("octeontx2-pf: ethtool fec mode support")
Addresses-Coverity-ID: 1501724 ("Unintentional integer overflow")
Addresses-Coverity-ID: 1501725 ("Unintentional integer overflow")
Addresses-Coverity-ID: 1501726 ("Unintentional integer overflow")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210411134316.80274-7-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-11 08:37:56 -06:00
Bhaskar Chowdhury 9c9b81c456 md: bcache: Trivial typo fixes in the file journal.c
s/condidate/candidate/
s/folowing/following/

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210411134316.80274-6-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-11 08:37:56 -06:00
Arnd Bergmann be3bacecec md: bcache: avoid -Wempty-body warnings
building with 'make W=1' shows a harmless warning for each user of the
EBUG_ON() macro:

drivers/md/bcache/bset.c: In function 'bch_btree_sort_partial':
drivers/md/bcache/util.h:30:55: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
   30 | #define EBUG_ON(cond)                   do { if (cond); } while (0)
      |                                                       ^
drivers/md/bcache/bset.c:1312:9: note: in expansion of macro 'EBUG_ON'
 1312 |         EBUG_ON(oldsize >= 0 && bch_count_data(b) != oldsize);
      |         ^~~~~~~

Reword the macro slightly to avoid the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210411134316.80274-5-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-11 08:37:56 -06:00
Yang Li f9a018e8a6 bcache: use NULL instead of using plain integer as pointer
This fixes the following sparse warnings:
drivers/md/bcache/features.c:22:16: warning: Using plain integer as NULL
pointer

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210411134316.80274-4-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-11 08:37:56 -06:00
Christoph Hellwig 11e9560e6c bcache: remove PTR_CACHE
Remove the PTR_CACHE inline and replace it with a direct dereference
of c->cache.

(Coly Li: fix the typo from PTR_BUCKET to PTR_CACHE in commit log)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210411134316.80274-3-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-11 08:37:55 -06:00
Zhiqiang Liu 13e1db65d2 bcache: reduce redundant code in bch_cached_dev_run()
In bch_cached_dev_run(), free(env[1])|free(env[2])|free(buf)
show up three times. This patch introduce out tag in
which free(env[1])|free(env[2])|free(buf) are only called
one time. If we need to call free() when errors occur,
we can set error code to ret, and then goto out tag directly.

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210411134316.80274-2-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-11 08:37:55 -06:00
Christoph Hellwig a8affc03a9 block: rename BIO_MAX_PAGES to BIO_MAX_VECS
Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed.  Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-11 07:47:48 -07:00
Linus Torvalds 9820b4dca0 for-5.12/drivers-2021-02-17
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Merge tag 'for-5.12/drivers-2021-02-17' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:

 - Remove the skd driver. It's been EOL for a long time (Damien)

 - NVMe pull requests
      - fix multipath handling of ->queue_rq errors (Chao Leng)
      - nvmet cleanups (Chaitanya Kulkarni)
      - add a quirk for buggy Amazon controller (Filippo Sironi)
      - avoid devm allocations in nvme-hwmon that don't interact well
        with fabrics (Hannes Reinecke)
      - sysfs cleanups (Jiapeng Chong)
      - fix nr_zones for multipath (Keith Busch)
      - nvme-tcp crash fix for no-data commands (Sagi Grimberg)
      - nvmet-tcp fixes (Sagi Grimberg)
      - add a missing __rcu annotation (Christoph)
      - failed reconnect fixes (Chao Leng)
      - various tracing improvements (Michal Krakowiak, Johannes
        Thumshirn)
      - switch the nvmet-fc assoc_list to use RCU protection (Leonid
        Ravich)
      - resync the status codes with the latest spec (Max Gurtovoy)
      - minor nvme-tcp improvements (Sagi Grimberg)
      - various cleanups (Rikard Falkeborn, Minwoo Im, Chaitanya
        Kulkarni, Israel Rukshin)

 - Floppy O_NDELAY fix (Denis)

 - MD pull request
      - raid5 chunk_sectors fix (Guoqing)

 - Use lore links (Kees)

 - Use DEFINE_SHOW_ATTRIBUTE for nbd (Liao)

 - loop lock scaling (Pavel)

 - mtip32xx PCI fixes (Bjorn)

 - bcache fixes (Kai, Dongdong)

 - Misc fixes (Tian, Yang, Guoqing, Joe, Andy)

* tag 'for-5.12/drivers-2021-02-17' of git://git.kernel.dk/linux-block: (64 commits)
  lightnvm: pblk: Replace guid_copy() with export_guid()/import_guid()
  lightnvm: fix unnecessary NULL check warnings
  nvme-tcp: fix crash triggered with a dataless request submission
  block: Replace lkml.org links with lore
  nbd: Convert to DEFINE_SHOW_ATTRIBUTE
  nvme: add 48-bit DMA address quirk for Amazon NVMe controllers
  nvme-hwmon: rework to avoid devm allocation
  nvmet: remove else at the end of the function
  nvmet: add nvmet_req_subsys() helper
  nvmet: use min of device_path and disk len
  nvmet: use invalid cmd opcode helper
  nvmet: use invalid cmd opcode helper
  nvmet: add helper to report invalid opcode
  nvmet: remove extra variable in id-ns handler
  nvmet: make nvmet_find_namespace() req based
  nvmet: return uniform error for invalid ns
  nvmet: set status to 0 in case for invalid nsid
  nvmet-fc: add a missing __rcu annotation to nvmet_fc_tgt_assoc.queues
  nvme-multipath: set nr_zones for zoned namespaces
  nvmet-tcp: fix potential race of tcp socket closing accept_work
  ...
2021-02-21 11:06:54 -08:00
Linus Torvalds 582cd91f69 for-5.12/block-2021-02-17
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Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block

Pull core block updates from Jens Axboe:
 "Another nice round of removing more code than what is added, mostly
  due to Christoph's relentless pursuit of tech debt removal/cleanups.
  This pull request contains:

   - Two series of BFQ improvements (Paolo, Jan, Jia)

   - Block iov_iter improvements (Pavel)

   - bsg error path fix (Pan)

   - blk-mq scheduler improvements (Jan)

   - -EBUSY discard fix (Jan)

   - bvec allocation improvements (Ming, Christoph)

   - bio allocation and init improvements (Christoph)

   - Store bdev pointer in bio instead of gendisk + partno (Christoph)

   - Block trace point cleanups (Christoph)

   - hard read-only vs read-only split (Christoph)

   - Block based swap cleanups (Christoph)

   - Zoned write granularity support (Damien)

   - Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)"

* tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits)
  mm: simplify swapdev_block
  sd_zbc: clear zone resources for non-zoned case
  block: introduce blk_queue_clear_zone_settings()
  zonefs: use zone write granularity as block size
  block: introduce zone_write_granularity limit
  block: use blk_queue_set_zoned in add_partition()
  nullb: use blk_queue_set_zoned() to setup zoned devices
  nvme: cleanup zone information initialization
  block: document zone_append_max_bytes attribute
  block: use bi_max_vecs to find the bvec pool
  md/raid10: remove dead code in reshape_request
  block: mark the bio as cloned in bio_iov_bvec_set
  block: set BIO_NO_PAGE_REF in bio_iov_bvec_set
  block: remove a layer of indentation in bio_iov_iter_get_pages
  block: turn the nr_iovecs argument to bio_alloc* into an unsigned short
  block: remove the 1 and 4 vec bvec_slabs entries
  block: streamline bvec_alloc
  block: factor out a bvec_alloc_gfp helper
  block: move struct biovec_slab to bio.c
  block: reuse BIO_INLINE_VECS for integrity bvecs
  ...
2021-02-21 11:02:48 -08:00
Joe Perches 6751c1e3cf bcache: Avoid comma separated statements
Use semicolons and braces.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10 08:06:00 -07:00
Kai Krakow afe78ab46f bcache: Move journal work to new flush wq
This is potentially long running and not latency sensitive, let's get
it out of the way of other latency sensitive events.

As observed in the previous commit, the `system_wq` comes easily
congested by bcache, and this fixes a few more stalls I was observing
every once in a while.

Let's not make this `WQ_MEM_RECLAIM` as it showed to reduce performance
of boot and file system operations in my tests. Also, without
`WQ_MEM_RECLAIM`, I no longer see desktop stalls. This matches the
previous behavior as `system_wq` also does no memory reclaim:

> // workqueue.c:
> system_wq = alloc_workqueue("events", 0, 0);

Cc: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10 08:06:00 -07:00
Kai Krakow d797bd9897 bcache: Give btree_io_wq correct semantics again
Before killing `btree_io_wq`, the queue was allocated using
`create_singlethread_workqueue()` which has `WQ_MEM_RECLAIM`. After
killing it, it no longer had this property but `system_wq` is not
single threaded.

Let's combine both worlds and make it multi threaded but able to
reclaim memory.

Cc: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10 08:06:00 -07:00
Kai Krakow 9f233ffe02 Revert "bcache: Kill btree_io_wq"
This reverts commit 56b30770b2.

With the btree using the `system_wq`, I seem to see a lot more desktop
latency than I should.

After some more investigation, it looks like the original assumption
of 56b3077 no longer is true, and bcache has a very high potential of
congesting the `system_wq`. In turn, this introduces laggy desktop
performance, IO stalls (at least with btrfs), and input events may be
delayed.

So let's revert this. It's important to note that the semantics of
using `system_wq` previously mean that `btree_io_wq` should be created
before and destroyed after other bcache wqs to keep the same
assumptions.

Cc: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10 08:06:00 -07:00
Kai Krakow d7fae7b4fa bcache: Fix register_device_aync typo
Should be `register_device_async`.

Cc: Coly Li <colyli@suse.de>
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10 08:06:00 -07:00
dongdong tao 71dda2a562 bcache: consider the fragmentation when update the writeback rate
Current way to calculate the writeback rate only considered the
dirty sectors, this usually works fine when the fragmentation
is not high, but it will give us unreasonable small rate when
we are under a situation that very few dirty sectors consumed
a lot dirty buckets. In some case, the dirty bucekts can reached
to CUTOFF_WRITEBACK_SYNC while the dirty data(sectors) not even
reached the writeback_percent, the writeback rate will still
be the minimum value (4k), thus it will cause all the writes to be
stucked in a non-writeback mode because of the slow writeback.

We accelerate the rate in 3 stages with different aggressiveness,
the first stage starts when dirty buckets percent reach above
BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW (50), the second is
BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID (57), the third is
BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH (64). By default
the first stage tries to writeback the amount of dirty data
in one bucket (on average) in (1 / (dirty_buckets_percent - 50)) second,
the second stage tries to writeback the amount of dirty data in one bucket
in (1 / (dirty_buckets_percent - 57)) * 100 millisecond, the third
stage tries to writeback the amount of dirty data in one bucket in
(1 / (dirty_buckets_percent - 64)) millisecond.

the initial rate at each stage can be controlled by 3 configurable
parameters writeback_rate_fp_term_{low|mid|high}, they are by default
1, 10, 1000, the hint of IO throughput that these values are trying
to achieve is described by above paragraph, the reason that
I choose those value as default is based on the testing and the
production data, below is some details:

A. When it comes to the low stage, there is still a bit far from the 70
   threshold, so we only want to give it a little bit push by setting the
   term to 1, it means the initial rate will be 170 if the fragment is 6,
   it is calculated by bucket_size/fragment, this rate is very small,
   but still much reasonable than the minimum 8.
   For a production bcache with unheavy workload, if the cache device
   is bigger than 1 TB, it may take hours to consume 1% buckets,
   so it is very possible to reclaim enough dirty buckets in this stage,
   thus to avoid entering the next stage.

B. If the dirty buckets ratio didn't turn around during the first stage,
   it comes to the mid stage, then it is necessary for mid stage
   to be more aggressive than low stage, so i choose the initial rate
   to be 10 times more than low stage, that means 1700 as the initial
   rate if the fragment is 6. This is some normal rate
   we usually see for a normal workload when writeback happens
   because of writeback_percent.

C. If the dirty buckets ratio didn't turn around during the low and mid
   stages, it comes to the third stage, and it is the last chance that
   we can turn around to avoid the horrible cutoff writeback sync issue,
   then we choose 100 times more aggressive than the mid stage, that
   means 170000 as the initial rate if the fragment is 6. This is also
   inferred from a production bcache, I've got one week's writeback rate
   data from a production bcache which has quite heavy workloads,
   again, the writeback is triggered by the writeback percent,
   the highest rate area is around 100000 to 240000, so I believe this
   kind aggressiveness at this stage is reasonable for production.
   And it should be mostly enough because the hint is trying to reclaim
   1000 bucket per second, and from that heavy production env,
   it is consuming 50 bucket per second on average in one week's data.

Option writeback_consider_fragment is to control whether we want
this feature to be on or off, it's on by default.

Lastly, below is the performance data for all the testing result,
including the data from production env:
https://docs.google.com/document/d/1AmbIEa_2MhB9bqhC3rfga9tp7n9YX9PLn0jSUxscVW0/edit?usp=sharing

Signed-off-by: dongdong tao <dongdong.tao@canonical.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10 08:05:59 -07:00
Coly Li 0df28cad06 bcache: only check feature sets when sb->version >= BCACHE_SB_VERSION_CDEV_WITH_FEATURES
For super block version < BCACHE_SB_VERSION_CDEV_WITH_FEATURES, it
doesn't make sense to check the feature sets. This patch checks
super block version in bch_has_feature_* routines, if the version
doesn't have feature sets yet, returns 0 (false) to the caller.

Fixes: 5342fd4255 ("bcache: set bcache device into read-only mode for BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET")
Fixes: ffa4703275 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Cc: stable@vger.kernel.org # 5.9+
Reported-and-tested-by: Bockholdt Arne <a.bockholdt@precitec-optronik.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-28 07:35:07 -07:00
Christoph Hellwig f65b95fe0c bcache: use bio_set_dev to assign ->bi_bdev
Always use the bio_set_dev helper to assign ->bi_bdev to make sure
other state related to the device is uptodate.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-26 08:50:01 -07:00
Ming Lei faa8e2c4fb bcache: don't pass BIOSET_NEED_BVECS for the 'bio_set' embedded in 'cache_set'
This bioset is just for allocating bio only from bio_next_split, and it
needn't bvecs, so remove the flag.

Cc: linux-bcache@vger.kernel.org
Cc: Coly Li <colyli@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24 21:24:09 -07:00
Christoph Hellwig 99dfc43ecb block: use ->bi_bdev for bio based I/O accounting
Rework the I/O accounting for bio based drivers to use ->bi_bdev.  This
means all drivers can now simply use bio_start_io_acct to start
accounting, and it will take partitions into account automatically.  To
end I/O account either bio_end_io_acct can be used if the driver never
remaps I/O to a different device, or bio_end_io_acct_remapped if the
driver did remap the I/O.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24 18:17:20 -07:00
Christoph Hellwig 309dca309f block: store a block_device pointer in struct bio
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device.  From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24 18:17:20 -07:00
Coly Li 5342fd4255 bcache: set bcache device into read-only mode for BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET
If BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET is set in incompat feature
set, it means the cache device is created with obsoleted layout with
obso_bucket_site_hi. Now bcache does not support this feature bit, a new
BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE incompat feature bit is added
for a better layout to support large bucket size.

For the legacy compatibility purpose, if a cache device created with
obsoleted BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET feature bit, all bcache
devices attached to this cache set should be set to read-only. Then the
dirty data can be written back to backing device before re-create the
cache device with BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE feature bit
by the latest bcache-tools.

This patch checks BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET feature bit
when running a cache set and attach a bcache device to the cache set. If
this bit is set,
- When run a cache set, print an error kernel message to indicate all
  following attached bcache device will be read-only.
- When attach a bcache device, print an error kernel message to indicate
  the attached bcache device will be read-only, and ask users to update
  to latest bcache-tools.

Such change is only for cache device whose bucket size >= 32MB, this is
for the zoned SSD and almost nobody uses such large bucket size at this
moment. If you don't explicit set a large bucket size for a zoned SSD,
such change is totally transparent to your bcache device.

Fixes: ffa4703275 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-09 09:21:03 -07:00
Coly Li b16671e8f4 bcache: introduce BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE for large bucket
When large bucket feature was added, BCH_FEATURE_INCOMPAT_LARGE_BUCKET
was introduced into the incompat feature set. It used bucket_size_hi
(which was added at the tail of struct cache_sb_disk) to extend current
16bit bucket size to 32bit with existing bucket_size in struct
cache_sb_disk.

This is not a good idea, there are two obvious problems,
- Bucket size is always value power of 2, if store log2(bucket size) in
  existing bucket_size of struct cache_sb_disk, it is unnecessary to add
  bucket_size_hi.
- Macro csum_set() assumes d[SB_JOURNAL_BUCKETS] is the last member in
  struct cache_sb_disk, bucket_size_hi was added after d[] which makes
  csum_set calculate an unexpected super block checksum.

To fix the above problems, this patch introduces a new incompat feature
bit BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE, when this bit is set, it
means bucket_size in struct cache_sb_disk stores the order of power-of-2
bucket size value. When user specifies a bucket size larger than 32768
sectors, BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE will be set to
incompat feature set, and bucket_size stores log2(bucket size) more
than store the real bucket size value.

The obsoleted BCH_FEATURE_INCOMPAT_LARGE_BUCKET won't be used anymore,
it is renamed to BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET and still only
recognized by kernel driver for legacy compatible purpose. The previous
bucket_size_hi is renmaed to obso_bucket_size_hi in struct cache_sb_disk
and not used in bcache-tools anymore.

For cache device created with BCH_FEATURE_INCOMPAT_LARGE_BUCKET feature,
bcache-tools and kernel driver still recognize the feature string and
display it as "obso_large_bucket".

With this change, the unnecessary extra space extend of bcache on-disk
super block can be avoided, and csum_set() may generate expected check
sum as well.

Fixes: ffa4703275 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-09 09:21:03 -07:00
Coly Li 1dfc0686c2 bcache: check unsupported feature sets for bcache register
This patch adds the check for features which is incompatible for
current supported feature sets.

Now if the bcache device created by bcache-tools has features that
current kernel doesn't support, read_super() will fail with error
messoage. E.g. if an unsupported incompatible feature detected,
bcache register will fail with dmesg "bcache: register_bcache() error :
Unsupported incompatible feature found".

Fixes: d721a43ff6 ("bcache: increase super block version for cache device and backing device")
Fixes: ffa4703275 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-09 09:21:03 -07:00
Coly Li f7b4943dea bcache: fix typo from SUUP to SUPP in features.h
This patch fixes the following typos,
from BCH_FEATURE_COMPAT_SUUP to BCH_FEATURE_COMPAT_SUPP
from BCH_FEATURE_INCOMPAT_SUUP to BCH_FEATURE_INCOMPAT_SUPP
from BCH_FEATURE_INCOMPAT_SUUP to BCH_FEATURE_RO_COMPAT_SUPP

Fixes: d721a43ff6 ("bcache: increase super block version for cache device and backing device")
Fixes: ffa4703275 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-09 09:21:03 -07:00
Yi Li e80927079f bcache: set pdev_set_uuid before scond loop iteration
There is no need to reassign pdev_set_uuid in the second loop iteration,
so move it to the place before second loop.

Signed-off-by: Yi Li <yili@winhong.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-09 09:21:03 -07:00
Zheng Yongjun 46926127d7 md/bcache: convert comma to semicolon
Replace a comma between expression statements by a semicolon.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Coly Li <colyli@sue.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-23 09:25:15 -07:00
Yi Li 117ae250cf bcache:remove a superfluous check in register_bcache
There have no reassign the bdev after check It is IS_ERR.
the double check !IS_ERR(bdev) is superfluous.

After commit 4e7b5671c6 ("block: remove i_bdev"),
"Switch the block device lookup interfaces to directly work with a dev_t
so that struct block_device references are only acquired by the
blkdev_get variants (and the blk-cgroup special case).  This means that
we now don't need an extra reference in the inode and can generally
simplify handling of struct block_device to keep the lookups contained
in the core block layer code."

so after lookup_bdev call, there no need to do bdput.

remove a superfluous check the bdev & don't call bdput after lookup_bdev.

Fixes: 4e7b5671c6a8("block: remove i_bdev")
Signed-off-by: Yi Li <yili@winhong.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-23 09:25:15 -07:00
Linus Torvalds 69f637c335 for-5.11/drivers-2020-12-14
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Merge tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Nothing major in here:

   - NVMe pull request from Christoph:
        - nvmet passthrough improvements (Chaitanya Kulkarni)
        - fcloop error injection support (James Smart)
        - read-only support for zoned namespaces without Zone Append
          (Javier González)
        - improve some error message (Minwoo Im)
        - reject I/O to offline fabrics namespaces (Victor Gladkov)
        - PCI queue allocation cleanups (Niklas Schnelle)
        - remove an unused allocation in nvmet (Amit Engel)
        - a Kconfig spelling fix (Colin Ian King)
        - nvme_req_qid simplication (Baolin Wang)

   - MD pull request from Song:
        - Fix race condition in md_ioctl() (Dae R. Jeong)
        - Initialize read_slot properly for raid10 (Kevin Vigor)
        - Code cleanup (Pankaj Gupta)
        - md-cluster resync/reshape fix (Zhao Heming)

   - Move null_blk into its own directory (Damien Le Moal)

   - null_blk zone and discard improvements (Damien Le Moal)

   - bcache race fix (Dongsheng Yang)

   - Set of rnbd fixes/improvements (Gioh Kim, Guoqing Jiang, Jack Wang,
     Lutz Pogrell, Md Haris Iqbal)

   - lightnvm NULL pointer deref fix (tangzhenhao)

   - sr in_interrupt() removal (Sebastian Andrzej Siewior)

   - FC endpoint security support for s390/dasd (Jan Höppner, Sebastian
     Ott, Vineeth Vijayan). From the s390 arch guys, arch bits included
     as it made it easier for them to funnel the feature through the
     block driver tree.

   - Follow up fixes (Colin Ian King)"

* tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block: (64 commits)
  block: drop dead assignments in loop_init()
  sr: Remove in_interrupt() usage in sr_init_command().
  sr: Switch the sector size back to 2048 if sr_read_sector() changed it.
  cdrom: Reset sector_size back it is not 2048.
  drivers/lightnvm: fix a null-ptr-deref bug in pblk-core.c
  null_blk: Move driver into its own directory
  null_blk: Allow controlling max_hw_sectors limit
  null_blk: discard zones on reset
  null_blk: cleanup discard handling
  null_blk: Improve implicit zone close
  null_blk: improve zone locking
  block: Align max_hw_sectors to logical blocksize
  null_blk: Fail zone append to conventional zones
  null_blk: Fix zone size initialization
  bcache: fix race between setting bdev state to none and new write request direct to backing
  block/rnbd: fix a null pointer dereference on dev->blk_symlink_name
  block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
  block/rnbd: call kobject_put in the failure path
  Documentation/ABI/rnbd-srv: add document for force_close
  block/rnbd-srv: close a mapped device from server side.
  ...
2020-12-16 13:09:32 -08:00
Dongsheng Yang df4ad53242 bcache: fix race between setting bdev state to none and new write request direct to backing
There is a race condition in detaching as below:
A. detaching			B. Write request
(1) writing back
(2) write back done, set bdev
    state to clean.
(3) cached_dev_put() and
    schedule_work(&dc->detach);
				(4) write data [0 - 4K] directly
				    into backing and ack to user.
(5) power-failure...

When we restart this bcache device, this bdev is clean but not detached,
and read [0 - 4K], we will get unexpected old data from cache device.

To fix this problem, set the bdev state to none when we writeback done
in detaching, and then if power-failure happened as above, the data in
cache will not be used in next bcache device starting, it's detached, we
will read the correct data from backing derectly.

Signed-off-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-07 13:25:16 -07:00
Christoph Hellwig 8446fe9255 block: switch partition lookup to use struct block_device
Use struct block_device to lookup partitions on a disk.  This removes
all usage of struct hd_struct from the I/O path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de>			[bcache]
Acked-by: Chao Yu <yuchao0@huawei.com>			[f2fs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:40 -07:00
Christoph Hellwig a782483cc1 block: remove the nr_sects field in struct hd_struct
Now that the hd_struct always has a block device attached to it, there is
no need for having two size field that just get out of sync.

Additionally the field in hd_struct did not use proper serialization,
possibly allowing for torn writes.  By only using the block_device field
this problem also gets fixed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de>			[bcache]
Acked-by: Chao Yu <yuchao0@huawei.com>			[f2fs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:40 -07:00
Christoph Hellwig 4e7b5671c6 block: remove i_bdev
Switch the block device lookup interfaces to directly work with a dev_t
so that struct block_device references are only acquired by the
blkdev_get variants (and the blk-cgroup special case).  This means that
we now don't need an extra reference in the inode and can generally
simplify handling of struct block_device to keep the lookups contained
in the core block layer code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Coly Li <colyli@suse.de>		[bcache]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:39 -07:00
Christoph Hellwig 8d65269fe8 block: add a bdev_kobj helper
Add a little helper to find the kobject for a struct block_device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Coly Li <colyli@suse.de>		[bcache]
Acked-by: David Sterba <dsterba@suse.com>	[btrfs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:39 -07:00
Christoph Hellwig a7cb3d2f09 block: remove __blkdev_driver_ioctl
Just open code it in the few callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-11-16 08:14:29 -07:00
Coly Li 4a784266c6 bcache: remove embedded struct cache_sb from struct cache_set
Since bcache code was merged into mainline kerrnel, each cache set only
as one single cache in it. The multiple caches framework is here but the
code is far from completed. Considering the multiple copies of cached
data can also be stored on e.g. md raid1 devices, it is unnecessary to
support multiple caches in one cache set indeed.

The previous preparation patches fix the dependencies of explicitly
making a cache set only have single cache. Now we don't have to maintain
an embedded partial super block in struct cache_set, the in-memory super
block can be directly referenced from struct cache.

This patch removes the embedded struct cache_sb from struct cache_set,
and fixes all locations where the superb lock was referenced from this
removed super block by referencing the in-memory super block of struct
cache.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 6f9414e0f6 bcache: check and set sync status on cache's in-memory super block
Currently the cache's sync status is checked and set on cache set's in-
memory partial super block. After removing the embedded struct cache_sb
from cache set and reference cache's in-memory super block from struct
cache_set, the sync status can set and check directly on cache's super
block.

This patch checks and sets the cache sync status directly on cache's
in-memory super block. This is a preparation for later removing embedded
struct cache_sb from struct cache_set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li ebaa1ac12b bcache: remove can_attach_cache()
After removing the embedded struct cache_sb from struct cache_set, cache
set will directly reference the in-memory super block of struct cache.
It is unnecessary to compare block_size, bucket_size and nr_in_set from
the identical in-memory super block in can_attach_cache().

This is a preparation patch for latter removing cache_set->sb from
struct cache_set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 08a1782881 bcache: don't check seq numbers in register_cache_set()
In order to update the partial super block of cache set, the seq numbers
of cache and cache set are checked in register_cache_set(). If cache's
seq number is larger than cache set's seq number, cache set must update
its partial super block from cache's super block. It is unncessary when
the embedded struct cache_sb is removed from struct cache set.

This patch removed the seq numbers checking from register_cache_set(),
because later there will be no such partial super block in struct cache
set, the cache set will directly reference in-memory super block from
struct cache. This is a preparation patch for removing embedded struct
cache_sb from struct cache_set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 63a96c05cd bcache: only use bucket_bytes() on struct cache
Because struct cache_set and struct cache both have struct cache_sb,
macro bucket_bytes() currently are used on both of them. When removing
the embedded struct cache_sb from struct cache_set, this macro won't be
used on struct cache_set anymore.

This patch unifies all bucket_bytes() usage only on struct cache, this is
one of the preparation to remove the embedded struct cache_sb from
struct cache_set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 3c4fae2982 bcache: remove useless bucket_pages()
It seems alloc_bucket_pages() is the only user of bucket_pages().
Considering alloc_bucket_pages() is removed from bcache code, it is safe
to remove the useless macro bucket_pages() now.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 421cf1c573 bcache: remove useless alloc_bucket_pages()
Now no one uses alloc_bucket_pages() anymore, remove it from bcache.h.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 4e1ebae3ee bcache: only use block_bytes() on struct cache
Because struct cache_set and struct cache both have struct cache_sb,
therefore macro block_bytes() can be used on both of them. When removing
the embedded struct cache_sb from struct cache_set, this macro won't be
used on struct cache_set anymore.

This patch unifies all block_bytes() usage only on struct cache, this is
one of the preparation to remove the embedded struct cache_sb from
struct cache_set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 1132e56e78 bcache: add set_uuid in struct cache_set
This patch adds a separated set_uuid[16] in struct cache_set, to store
the uuid of the cache set. This is the preparation to remove the
embedded struct cache_sb from struct cache_set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:30 -06:00
Coly Li 08fdb2cddb bcache: remove for_each_cache()
Since now each cache_set explicitly has single cache, for_each_cache()
is unnecessary. This patch removes this macro, and update all locations
where it is used, and makes sure all code logic still being consistent.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:29 -06:00
Coly Li 697e23495c bcache: explicitly make cache_set only have single cache
Currently although the bcache code has a framework for multiple caches
in a cache set, but indeed the multiple caches never completed and users
use md raid1 for multiple copies of the cached data.

This patch does the following change in struct cache_set, to explicitly
make a cache_set only have single cache,
- Change pointer array "*cache[MAX_CACHES_PER_SET]" to a single pointer
  "*cache".
- Remove pointer array "*cache_by_alloc[MAX_CACHES_PER_SET]".
- Remove "caches_loaded".

Now the code looks as exactly what it does in practic: only one cache is
used in the cache set.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:29 -06:00
Coly Li 17e4aed830 bcache: remove 'int n' from parameter list of bch_bucket_alloc_set()
The parameter 'int n' from bch_bucket_alloc_set() is not cleared
defined. From the code comments n is the number of buckets to alloc, but
from the code itself 'n' is the maximum cache to iterate. Indeed all the
locations where bch_bucket_alloc_set() is called, 'n' is alwasy 1.

This patch removes the confused and unnecessary 'int n' from parameter
list of  bch_bucket_alloc_set(), and explicitly allocates only 1 bucket
for its caller.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:29 -06:00
Qinglang Miao 84e5d1363c bcache: Convert to DEFINE_SHOW_ATTRIBUTE
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.

As inode->iprivate equals to third parameter of
debugfs_create_file() which is NULL. So it's equivalent
to original code logic.

Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:29 -06:00
Dongsheng Yang 7e59c506c3 bcache: check c->root with IS_ERR_OR_NULL() in mca_reserve()
In mca_reserve(c) macro, we are checking root whether is NULL or not.
But that's not enough, when we read the root node in run_cache_set(),
if we got an error in bch_btree_node_read_done(), we will return
ERR_PTR(-EIO) to c->root.

And then we will go continue to unregister, but before calling
unregister_shrinker(&c->shrink), there is a possibility to call
bch_mca_count(), and we would get a crash with call trace like that:

[ 2149.876008] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000b5
... ...
[ 2150.598931] Call trace:
[ 2150.606439]  bch_mca_count+0x58/0x98 [escache]
[ 2150.615866]  do_shrink_slab+0x54/0x310
[ 2150.624429]  shrink_slab+0x248/0x2d0
[ 2150.632633]  drop_slab_node+0x54/0x88
[ 2150.640746]  drop_slab+0x50/0x88
[ 2150.648228]  drop_caches_sysctl_handler+0xf0/0x118
[ 2150.657219]  proc_sys_call_handler.isra.18+0xb8/0x110
[ 2150.666342]  proc_sys_write+0x40/0x50
[ 2150.673889]  __vfs_write+0x48/0x90
[ 2150.681095]  vfs_write+0xac/0x1b8
[ 2150.688145]  ksys_write+0x6c/0xd0
[ 2150.695127]  __arm64_sys_write+0x24/0x30
[ 2150.702749]  el0_svc_handler+0xa0/0x128
[ 2150.710296]  el0_svc+0x8/0xc

Signed-off-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:29 -06:00
Coly Li a58e88bfdc bcache: share register sysfs with async register
Previously the experimental async registration uses a separate sysfs
file register_async. Now the async registration code seems working well
for a while, we can do furtuher testing with it now.

This patch changes the async bcache registration shares the same sysfs
file /sys/fs/bcache/register (and register_quiet). Async registration
will be default behavior if BCACHE_ASYNC_REGISTRATION is set in kernel
configure. By default, BCACHE_ASYNC_REGISTRATION is not configured yet.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02 14:25:29 -06:00
Christoph Hellwig c2e4cd57cf block: lift setting the readahead size into the block layer
Drivers shouldn't really mess with the readahead size, as that is a VM
concept.  Instead set it based on the optimal I/O size by lifting the
algorithm from the md driver when registering the disk.  Also set
bdi->io_pages there as well by applying the same scheme based on
max_sectors.  To ensure the limits work well for stacking drivers a
new helper is added to update the readahead limits from the block
limits, which is also called from disk_stack_limits.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-24 13:43:39 -06:00
Christoph Hellwig 5d4ce78b25 bcache: inherit the optimal I/O size
Inherit the optimal I/O size setting just like the readahead window,
as any reason to do larger I/O does not apply to just readahead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-24 13:43:38 -06:00
Song Liu 0806e60f31 bcache: use part_[begin|end]_io_acct instead of disk_[begin|end]_io_acct
This enables proper statistics in /proc/diskstats for bcache partitions.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Coly Li <colyli@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-11 16:41:30 -06:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds e0fc99e21e for-5.9/drivers-20200803
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Merge tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:

 - NVMe:
      - ZNS support (Aravind, Keith, Matias, Niklas)
      - Misc cleanups, optimizations, fixes (Baolin, Chaitanya, David,
        Dongli, Max, Sagi)

 - null_blk zone capacity support (Aravind)

 - MD:
      - raid5/6 fixes (ChangSyun)
      - Warning fixes (Damien)
      - raid5 stripe fixes (Guoqing, Song, Yufen)
      - sysfs deadlock fix (Junxiao)
      - raid10 deadlock fix (Vitaly)

 - struct_size conversions (Gustavo)

 - Set of bcache updates/fixes (Coly)

* tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block: (117 commits)
  md/raid5: Allow degraded raid6 to do rmw
  md/raid5: Fix Force reconstruct-write io stuck in degraded raid5
  raid5: don't duplicate code for different paths in handle_stripe
  raid5-cache: hold spinlock instead of mutex in r5c_journal_mode_show
  md: print errno in super_written
  md/raid5: remove the redundant setting of STRIPE_HANDLE
  md: register new md sysfs file 'uuid' read-only
  md: fix max sectors calculation for super 1.0
  nvme-loop: remove extra variable in create ctrl
  nvme-loop: set ctrl state connecting after init
  nvme-multipath: do not fall back to __nvme_find_path() for non-optimized paths
  nvme-multipath: fix logic for non-optimized paths
  nvme-rdma: fix controller reset hang during traffic
  nvme-tcp: fix controller reset hang during traffic
  nvmet: introduce the passthru Kconfig option
  nvmet: introduce the passthru configfs interface
  nvmet: Add passthru enable/disable helpers
  nvmet: add passthru code to process commands
  nvme: export nvme_find_get_ns() and nvme_put_ns()
  nvme: introduce nvme_ctrl_get_by_path()
  ...
2020-08-05 10:51:40 -07:00
Coly Li c5be1f2c5b bcache: use disk_{start,end}_io_acct() to count I/O for bcache device
This patch is a fix to patch "bcache: fix bio_{start,end}_io_acct with
proper device". The previous patch uses a hack to temporarily set
bi_disk to bcache device, which is mistaken too.

As Christoph suggests, this patch uses disk_{start,end}_io_acct() to
count I/O for bcache device in the correct way.

Fixes: 85750aeb74 ("bcache: use bio_{start,end}_io_acct")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-28 09:14:52 -06:00
Coly Li a2f32ee8fd bcache: fix bio_{start,end}_io_acct with proper device
Commit 85750aeb74 ("bcache: use bio_{start,end}_io_acct") moves the
io account code to the location after bio_set_dev(bio, dc->bdev) in
cached_dev_make_request(). Then the account is performed incorrectly on
backing device, indeed the I/O should be counted to bcache device like
/dev/bcache0.

With the mistaken I/O account, iostat does not display I/O counts for
bcache device and all the numbers go to backing device. In writeback
mode, the hard drive may have 340K+ IOPS which is impossible and wrong
for spinning disk.

This patch introduces bch_bio_start_io_acct() and bch_bio_end_io_acct(),
which switches bio->bi_disk to bcache device before calling
bio_start_io_acct() or bio_end_io_acct(). Now the I/Os are counted to
bcache device, and bcache device, cache device and backing device have
their correct I/O count information back.

Fixes: 85750aeb74 ("bcache: use bio_{start,end}_io_acct")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:21 -06:00
Coly Li 4e4d4e0962 bcache: avoid extra memory consumption in struct bbio for large bucket size
Bcache uses struct bbio to do I/Os for meta data pages like uuids,
disk_buckets, prio_buckets, and btree nodes.

Example writing a btree node onto cache device, the process is,
- Allocate a struct bbio from mempool c->bio_meta.
- Inside struct bbio embedded a struct bio, initialize bi_inline_vecs
  for this embedded bio.
- Call bch_bio_map() to map each meta data page to each bv from the
  inlined  bi_io_vec table.
- Call bch_submit_bbio() to submit the bio into underlying block layer.
- When the I/O completed, only release the struct bbio, don't touch the
  reference counter of the meta data pages.

The struct bbio is defined as,
738 struct bbio {
739     unsigned int            submit_time_us;
	[snipped]
748     struct bio              bio;
749 };

Because struct bio is embedded at the end of struct bbio, therefore the
actual size of struct bbio is sizeof(struct bio) + size of the embedded
bio->bi_inline_vecs.

Now all the meta data bucket size are limited to meta_bucket_pages(), if
the bucket size is large than meta_bucket_pages()*PAGE_SECTORS, rested
space in the bucket is unused. Therefore the most used space in meta
bucket is (1<<MAX_ORDER) pages, or (1<<CONFIG_FORCE_MAX_ZONEORDER) if it
is configured.

Therefore for large bucket size, it is unnecessary to calculate the
allocation size of mempool c->bio_meta as,
	mempool_init_kmalloc_pool(&c->bio_meta, 2,
			sizeof(struct bbio) +
			sizeof(struct bio_vec) * bucket_pages(c))
It is too large, neither the Linux buddy allocator cannot allocate so
much continuous pages, nor the extra allocated pages are wasted.

This patch replace bucket_pages() to meta_bucket_pages() in two places,
- In bch_cache_set_alloc(), when initialize mempool c->bio_meta, uses
  sizeof(struct bbio) + sizeof(struct bio_vec) * bucket_pages(c) to set
  the allocating object size.
- In bch_bbio_alloc(), when calling bio_init() to set inline bvec talbe
  bi_inline_bvecs, uses meta_bucket_pages() to indicate number of the
  inline bio vencs number.

Now the maximum size of embedded bio inside struct bbio exactly matches
the limit of meta_bucket_pages(), no extra page wasted.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:21 -06:00
Coly Li 6907dc498f bcache: avoid extra memory allocation from mempool c->fill_iter
Mempool c->fill_iter is used to allocate memory for struct btree_iter in
bch_btree_node_read_done() to iterate all keys of a read-in btree node.

The allocation size is defined in bch_cache_set_alloc() by,
  mempool_init_kmalloc_pool(&c->fill_iter, 1, iter_size))
where iter_size is defined by a calculation,
  (sb->bucket_size / sb->block_size + 1) * sizeof(struct btree_iter_set)

For 16bit width bucket_size the calculation is OK, but now the bucket
size is extended to 32bit, the bucket size can be 2GB. By the above
calculation, iter_size can be 2048 pages (order 11 is still accepted by
buddy allocator).

But the actual size holds the bkeys in meta data bucket is limited to
meta_bucket_pages() already, which is 16MB. By the above calculation,
if replace sb->bucket_size by meta_bucket_pages() * PAGE_SECTORS, the
result is 16 pages. This is the size large enough for the mempool
allocation to struct btree_iter.

Therefore in worst case every time mempool c->fill_iter allocates, at
most 4080 pages are wasted and won't be used. Therefore this patch uses
meta_bucket_pages() * PAGE_SECTORS to calculate the iter size in
bch_cache_set_alloc(), to avoid extra memory allocation from mempool
c->fill_iter.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:21 -06:00
Coly Li 092bd54d69 bcache: add sysfs file to display feature sets information of cache set
The following three sysfs files are created to display according feature
set information of bcache:
	/sys/fs/bcache/<cache set UUID>/internal/feature_compat
	/sys/fs/bcache/<cache set UUID>/internal/feature_ro_compat
	/sys/fs/bcache/<cache set UUID>/internal/feature_incompat
is added by this patch, to display feature sets information of the cache
set.

Now only an incompat feature 'large_bucket' added in bcache, the sysfs
file content is:
        [large_bucket]
string large_bucket means the running bcache drive supports incompat
feature 'large_bucket', the wrapping [] means the 'large_bucket' feature
is currently enabled on this cache set.

This patch is ready to display compat and ro_compat features, in future
once bcache code implements such feature sets, the according feature
strings will be displayed in their sysfs files too.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:21 -06:00
Coly Li ffa4703275 bcache: add bucket_size_hi into struct cache_sb_disk for large bucket
The large bucket feature is to extend bucket_size from 16bit to 32bit.

When create cache device on zoned device (e.g. zoned NVMe SSD), making
a single bucket cover one or more zones of the zoned device is the
simplest way to support zoned device as cache by bcache.

But current maximum bucket size is 16MB and a typical zone size of zoned
device is 256MB, this is the major motiviation to extend bucket size to
a larger bit width.

This patch is the basic and first change to support large bucket size,
the major changes it makes are,
- Add BCH_FEATURE_INCOMPAT_LARGE_BUCKET for the large bucket feature,
  INCOMPAT means it introduces incompatible on-disk format change.
- Add BCH_FEATURE_INCOMPAT_FUNCS(large_bucket, LARGE_BUCKET) routines.
- Adds __le16 bucket_size_hi into struct cache_sb_disk at offset 0x8d0
  for the on-disk super block format.
- For the in-memory super block struct cache_sb, member bucket_size is
  extended from __u16 to __32.
- Add get_bucket_size() to combine the bucket_size and bucket_size_hi
  from struct cache_sb_disk into an unsigned int value.

Since we already have large bucket size helpers meta_bucket_pages(),
meta_bucket_bytes() and alloc_meta_bucket_pages(), they make sure when
bucket size > 8MB, the memory allocation for bcache meta data bucket
won't fail no matter how large the bucket size extended. So these meta
data buckets are handled properly when the bucket size width increase
from 16bit to 32bit, we don't need to worry about them.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:21 -06:00
Coly Li f9c32a5a90 bcache: handle btree node memory allocation properly for bucket size > 8MB
Currently the bcache internal btree node occupies a whole bucket. When
loading the btree node from cache device into memory, mca_data_alloc()
will call bch_btree_keys_alloc() to allocate memory for the whole bucket
size, ilog2(b->c->btree_pages) is send to bch_btree_keys_alloc() as the
parameter 'page_order'.

c->btree_pages is set as bucket_pages() in bch_cache_set_alloc(), for
bucket size > 8MB, ilog2(b->c->btree_pages) is 12 for 4KB page size. By
default the maximum page order __get_free_pages() accepts is MAX_ORDER
(11), in this condition bch_btree_keys_alloc() will always fail.

Because of other over-page-order allocation failure fails the cache
device registration, such btree node allocation failure wasn't observed
during runtime. After other blocking page allocation failures for bucket
size > 8MB, this btree node allocation issue may trigger potentical risk
e.g. infinite dead-loop to retry btree node allocation after failure.

This patch fixes the potential problem by setting c->btree_pages to
meta_bucket_pages() in bch_cache_set_alloc(). In the condition that
bucket size > 8MB, meta_bucket_pages() will always return a number which
won't exceed the maximum page order of the buddy allocator.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li bf6af17065 bcache: handle cache set verify_ondisk properly for bucket size > 8MB
In bch_btree_cache_alloc() when CONFIG_BCACHE_DEBUG is configured,
allocate memory for c->verify_ondisk may fail if the bucket size > 8MB,
which will require __get_free_pages() to allocate continuous pages
with order > 11 (the default MAX_ORDER of Linux buddy allocator). Such
over size allocation will fail, and cause 2 problems,
- When CONFIG_BCACHE_DEBUG is configured,  bch_btree_verify() does not
  work, because c->verify_ondisk is NULL and bch_btree_verify() returns
  immediately.
- bch_btree_cache_alloc() will fail due to c->verify_ondisk allocation
  failed, then the whole cache device registration fails. And because of
  this failure, the first problem of bch_btree_verify() has no chance to
  be triggered.

This patch fixes the above problem by two means,
1) If pages allocation of c->verify_ondisk fails, set it to NULL and
   returns bch_btree_cache_alloc() with -ENOMEM.
2) When calling __get_free_pages() to allocate c->verify_ondisk pages,
   use ilog2(meta_bucket_pages(&c->sb)) to make sure ilog2() will always
   generate a pages order <= MAX_ORDER (or CONFIG_FORCE_MAX_ZONEORDER).
   Then the buddy system won't directly reject the allocation request.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li c954ac8d66 bcache: handle cache prio_buckets and disk_buckets properly for bucket size > 8MB
Similar to c->uuids, struct cache's prio_buckets and disk_buckets also
have the potential memory allocation failure during cache registration
if the bucket size > 8MB.

ca->prio_buckets can be stored on cache device in multiple buckets, its
in-memory space is allocated by kzalloc() interface but normally
allocated by alloc_pages() because the size > KMALLOC_MAX_CACHE_SIZE.

So allocation of ca->prio_buckets has the MAX_ORDER restriction too. If
the bucket size > 8MB, by default the page allocator will fail because
the page order > 11 (default MAX_ORDER value). ca->prio_buckets should
also use meta_bucket_bytes(), meta_bucket_pages() to decide its memory
size and use alloc_meta_bucket_pages() to allocate pages, to avoid the
allocation failure during cache set registration when bucket size > 8MB.

ca->disk_buckets is a single bucket size memory buffer, it is used to
iterate each bucket of ca->prio_buckets, and compose the bio based on
memory of ca->disk_buckets, then write ca->disk_buckets memory to cache
disk one-by-one for each bucket of ca->prio_buckets. ca->disk_buckets
should have in-memory size exact to the meta_bucket_pages(), this is the
size that ca->prio_buckets will be stored into each on-disk bucket.

This patch fixes the above issues and handle cache's prio_buckets and
disk_buckets properly for bucket size larger than 8MB.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li 21e478ddb2 bcache: handle c->uuids properly for bucket size > 8MB
Bcache allocates a whole bucket to store c->uuids on cache device, and
allocates continuous pages to store it in-memory. When the bucket size
exceeds maximum allocable continuous pages, bch_cache_set_alloc() will
fail and cache device registration will fail.

This patch allocates c->uuids by alloc_meta_bucket_pages(), and uses
ilog2(meta_bucket_pages(c)) to indicate order of c->uuids pages when
free it. When writing c->uuids to cache device, its size is decided
by meta_bucket_pages(c) * PAGE_SECTORS. Now c->uuids is properly handled
for bucket size > 8MB.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li de1fafab64 bcache: introduce meta_bucket_pages() related helper routines
Currently the in-memory meta data like c->uuids or c->disk_buckets
are allocated by alloc_bucket_pages(). The macro alloc_bucket_pages()
calls __get_free_pages() to allocated continuous pages with order
indicated by ilog2(bucket_pages(c)),
 #define alloc_bucket_pages(gfp, c)                      \
     ((void *) __get_free_pages(__GFP_ZERO|gfp, ilog2(bucket_pages(c))))

The maximum order is defined as MAX_ORDER, the default value is 11 (and
can be overwritten by CONFIG_FORCE_MAX_ZONEORDER). In bcache code the
maximum bucket size width is 16bits, this is restricted both by KEY_SIZE
size and bucket_size size from struct cache_sb_disk. The maximum 16bits
width and power-of-2 value is (1<<15) in unit of sector (512byte). It
means the maximum value of bucket size in bytes is (1<<24) bytes a.k.a
4096 pages.

When the bucket size is set to maximum permitted value, ilog2(4096) is
12, which exceeds the default maximum order __get_free_pages() can
accepted, the failed pages allocation will fail cache set registration
procedure and print a kernel oops message for the exceeded pages order.

This patch introduces meta_bucket_pages(), meta_bucket_bytes(), and
alloc_bucket_pages() helper routines. meta_bucket_pages() indicates the
maximum pages can be allocated to meta data bucket, meta_bucket_bytes()
indicates the according maximum bytes, and alloc_bucket_pages() does
the pages allocation for meta bucket. Because meta_bucket_pages()
chooses the smaller value among the bucket size and MAX_ORDER_NR_PAGES,
it still works when MAX_ORDER overwritten by CONFIG_FORCE_MAX_ZONEORDER.

Following patches will use these helper routines to decide maximum pages
can be allocated for different meta data buckets. If the bucket size is
larger than meta_bucket_bytes(), the bcache registration can continue to
success, just the space more than meta_bucket_bytes() inside the bucket
is wasted. Comparing bcache failed for large bucket size, wasting some
space for meta data buckets is acceptable at this moment.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li 198efa35c5 bcache: move bucket related code into read_super_common()
Setting sb->first_bucket and checking sb->keys indeed are only for cache
device, it does not make sense to do them in read_super() for backing
device too.

This patch moves the related code piece into read_super_common()
explicitly for cache device and avoid the confusion.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li d721a43ff6 bcache: increase super block version for cache device and backing device
The new added super block version BCACHE_SB_VERSION_BDEV_WITH_FEATURES
(5) BCACHE_SB_VERSION_CDEV_WITH_FEATURES value (6), is for the feature
set bits.

Devices have super block version equal to the new version will have
three new members for feature set bits in the on-disk super block,
        __le64                  feature_compat;
        __le64                  feature_incompat;
        __le64                  feature_ro_compat;

They are used for further new features which may introduce on-disk
format change, and avoid unncessary super block version increase.

The very basic features handling code skeleton is also initialized in
this patch.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li 117f636ea6 bcache: fix super block seq numbers comparision in register_cache_set()
In register_cache_set(), c is pointer to struct cache_set, and ca is
pointer to struct cache, if ca->sb.seq > c->sb.seq, it means this
registering cache has up to date version and other members, the in-
memory version and other members should be updated to the newer value.

But current implementation makes a cache set only has a single cache
device, so the above assumption works well except for a special case.
The execption is when a cache device new created and both ca->sb.seq and
c->sb.seq are 0, because the super block is never flushed out yet. In
the location for the following if() check,
2156         if (ca->sb.seq > c->sb.seq) {
2157                 c->sb.version           = ca->sb.version;
2158                 memcpy(c->sb.set_uuid, ca->sb.set_uuid, 16);
2159                 c->sb.flags             = ca->sb.flags;
2160                 c->sb.seq               = ca->sb.seq;
2161                 pr_debug("set version = %llu\n", c->sb.version);
2162         }
c->sb.version is not initialized yet and valued 0. When ca->sb.seq is 0,
the if() check will fail (because both values are 0), and the cache set
version, set_uuid, flags and seq won't be updated.

The above problem is hiden for current code, because the bucket size is
compatible among different super block version. And the next time when
running cache set again, ca->sb.seq will be larger than 0 and cache set
super block version will be updated properly.

But if the large bucket feature is enabled,  sb->bucket_size is the low
16bits of the bucket size. For a power of 2 value, when the actual
bucket size exceeds 16bit width, sb->bucket_size will always be 0. Then
read_super_common() will fail because the if() check to
is_power_of_2(sb->bucket_size) is false. This is how the long time
hidden bug is triggered.

This patch modifies the if() check to the following way,
2156         if (ca->sb.seq > c->sb.seq || c->sb.seq == 0) {
Then cache set's version, set_uuid, flags and seq will always be updated
corectly including for a new created cache device.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li a42d3c642c bcache: disassemble the big if() checks in bch_cache_set_alloc()
In bch_cache_set_alloc() there is a big if() checks combined by 11 items
together. When this big if() statement fails, it is difficult to tell
exactly which item fails indeed.

This patch disassembles this big if() checks into 11 single if() checks,
which makes code debug more easier.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li c557a5f7bb bcache: add more accurate error information in read_super_common()
The improperly set bucket or block size will trigger error in
read_super_common(). For large bucket size, a more accurate error message
for invalid bucket or block size is necessary.

This patch disassembles the combined if() checks into multiple single
if() check, and provide more accurate error message for each check
failure condition.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li 5b21403c7f bcache: add read_super_common() to read major part of super block
Later patches will introduce feature set bits to on-disk super block and
increase super block version. Current code in read_super() which reads
common part of super block for version BCACHE_SB_VERSION_CDEV and version
BCACHE_SB_VERSION_CDEV_WITH_UUID will be shared with the new version.

Therefore this patch moves the reusable part into read_super_common(),
this preparation patch will make later patches more simplier and only
focus on new feature set bits.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li 7a14812679 bcache: fix overflow in offset_to_stripe()
offset_to_stripe() returns the stripe number (in type unsigned int) from
an offset (in type uint64_t) by the following calculation,
	do_div(offset, d->stripe_size);
For large capacity backing device (e.g. 18TB) with small stripe size
(e.g. 4KB), the result is 4831838208 and exceeds UINT_MAX. The actual
returned value which caller receives is 536870912, due to the overflow.

Indeed in bcache_device_init(), bcache_device->nr_stripes is limited in
range [1, INT_MAX]. Therefore all valid stripe numbers in bcache are
in range [0, bcache_dev->nr_stripes - 1].

This patch adds a upper limition check in offset_to_stripe(): the max
valid stripe number should be less than bcache_device->nr_stripes. If
the calculated stripe number from do_div() is equal to or larger than
bcache_device->nr_stripe, -EINVAL will be returned. (Normally nr_stripes
is less than INT_MAX, exceeding upper limitation doesn't mean overflow,
therefore -EOVERFLOW is not used as error code.)

This patch also changes nr_stripes' type of struct bcache_device from
'unsigned int' to 'int', and return value type of offset_to_stripe()
from 'unsigned int' to 'int', to match their exact data ranges.

All locations where bcache_device->nr_stripes and offset_to_stripe() are
referenced also get updated for the above type change.

Reported-and-tested-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1783075
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Coly Li 65f0f017e7 bcache: avoid nr_stripes overflow in bcache_device_init()
For some block devices which large capacity (e.g. 8TB) but small io_opt
size (e.g. 8 sectors), in bcache_device_init() the stripes number calcu-
lated by,
	DIV_ROUND_UP_ULL(sectors, d->stripe_size);
might be overflow to the unsigned int bcache_device->nr_stripes.

This patch uses the uint64_t variable to store DIV_ROUND_UP_ULL()
and after the value is checked to be available in unsigned int range,
sets it to bache_device->nr_stripes. Then the overflow is avoided.

Reported-and-tested-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1783075
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Gustavo A. R. Silva 29f1d5cace bcache: Use struct_size() in kzalloc()
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

This code was detected with the help of Coccinelle and, audited and
fixed manually.

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Gustavo A. R. Silva 6706ad5643 bcache: movinggc: Use struct_size() helper in kzalloc()
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

This code was detected with the help of Coccinelle and, audited and
fixed manually.

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Xu Wang 7236657c6b bcache: writeback: Remove unneeded variable i
Remove unneeded variable i in bch_dirty_init_thread().

Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:20 -06:00
Xu Wang ef4eeb855f bcache: journel: use for_each_clear_bit() to simplify the code
Using for_each_clear_bit() to simplify the code.

Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:19 -06:00
Coly Li 5fe4886785 bcache: allocate meta data pages as compound pages
There are some meta data of bcache are allocated by multiple pages,
and they are used as bio bv_page for I/Os to the cache device. for
example cache_set->uuids, cache->disk_buckets, journal_write->data,
bset_tree->data.

For such meta data memory, all the allocated pages should be treated
as a single memory block. Then the memory management and underlying I/O
code can treat them more clearly.

This patch adds __GFP_COMP flag to all the location allocating >0 order
pages for the above mentioned meta data. Then their pages are treated
as compound pages now.

Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:19 -06:00
Jean Delvare 6acd193b26 bcache: Fix typo in Kconfig name
registraion -> registration

Fixes: 0c8d3fcead ("bcache: configure the asynchronous registertion to be experimental")
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Coly Li <colyli@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25 07:38:19 -06:00
Christoph Hellwig 21cf866145 writeback: remove bdi->congested_fn
Except for pktdvd, the only places setting congested bits are file
systems that allocate their own backing_dev_info structures.  And
pktdvd is a deprecated driver that isn't useful in stack setup
either.  So remove the dead congested_fn stacking infrastructure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>
[axboe: fixup unused variables in bcache/request.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 17:20:46 -06:00
Christoph Hellwig ed00aabd5e block: rename generic_make_request to submit_bio_noacct
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:24 -06:00
Christoph Hellwig c62b37d96b block: move ->make_request_fn to struct block_device_operations
The make_request_fn is a little weird in that it sits directly in
struct request_queue instead of an operation vector.  Replace it with
a block_device_operations method called submit_bio (which describes much
better what it does).  Also remove the request_queue argument to it, as
the queue can be derived pretty trivially from the bio.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:24 -06:00
Christoph Hellwig 987a0ef88b bcache: stop setting ->queuedata
Nothing in bcache actually uses the ->queuedata field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:23 -06:00