linux-toradex.git/drivers/md/bcache/btree.c, branch v5.17

bcache: Revert "bcache: use bvec_virt"

2021-11-08T13:23:17+00:00

This reverts commit 2fd3e5efe791946be0957c8e1eed9560b541fe46.

The above commit replaces page_address(bv->bv_page) by bvec_virt(bv) to
avoid directly access to bv->bv_page, but in situation bv->bv_offset is
not zero and page_address(bv->bv_page) is not equal to bvec_virt(bv). In
such case a memory corruption may happen because memory in next page is
tainted by following line in do_btree_node_write(),
	memcpy(bvec_virt(bv), addr, PAGE_SIZE);

This patch reverts the mentioned commit to avoid the memory corruption.

Fixes: 2fd3e5efe791 ("bcache: use bvec_virt")
Signed-off-by: Coly Li 
Cc: Christoph Hellwig 
Cc: stable@vger.kernel.org # 5.15
Signed-off-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20211103151041.70516-1-colyli@suse.de
Signed-off-by: Jens Axboe

bcache: remove bch_crc64_update

2021-10-20T14:40:54+00:00

bch_crc64_update is an entirely pointless wrapper around crc64_be.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Coly Li 
Link: https://lore.kernel.org/r/20211020143812.6403-9-colyli@suse.de
Signed-off-by: Jens Axboe

bcache: use bvec_virt

2021-08-16T16:50:33+00:00

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 
Reviewed-by: Coly Li 
Link: https://lore.kernel.org/r/20210804095634.460779-10-hch@lst.de
Signed-off-by: Jens Axboe

bcache: remove PTR_CACHE

2021-04-11T14:37:55+00:00

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 
Signed-off-by: Coly Li 
Link: https://lore.kernel.org/r/20210411134316.80274-3-colyli@suse.de
Signed-off-by: Jens Axboe

bcache: Give btree_io_wq correct semantics again

2021-02-10T15:06:00+00:00

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 
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow 
Signed-off-by: Coly Li 
Signed-off-by: Jens Axboe

Revert "bcache: Kill btree_io_wq"

2021-02-10T15:06:00+00:00

This reverts commit 56b30770b27d54d68ad51eccc6d888282b568cee.

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 
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow 
Signed-off-by: Coly Li 
Signed-off-by: Jens Axboe

bcache: remove embedded struct cache_sb from struct cache_set

2020-10-02T20:25:30+00:00

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 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe

bcache: only use block_bytes() on struct cache

2020-10-02T20:25:30+00:00

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 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe

bcache: remove for_each_cache()

2020-10-02T20:25:29+00:00

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 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe

bcache: remove 'int n' from parameter list of bch_bucket_alloc_set()

2020-10-02T20:25:29+00:00

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 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe