Patch series "zram: support algorithm-specific parameters".
This patchset adds support for algorithm-specific parameters. For now,
only deflate-specific winbits can be configured, which fixes deflate
support on some s390 setups.
This patch (of 2):
Use more generic name because this will be default "un-set"
value for more params in the future.
Link: https://lkml.kernel.org/r/20250514024825.1745489-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/20250514024825.1745489-2-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Support pre-trained dictionary param. lz4 doesn't mandate specific format
of the dictionary and even zstd --train can be used to train a dictionary
for lz4, according to [1].
TEST
====
*** lz4
/sys/block/zram0/mm_stat
1750654976 664188565 676864000 0 676864000 1 0 34288 34288
*** lz4 dict=/etc/lz4-dict-amd64
/sys/block/zram0/mm_stat
1750638592 619891141 632053760 0 632053760 1 0 34278 34278
*** lz4 level=5 dict=/etc/lz4-dict-amd64
/sys/block/zram0/mm_stat
1750638592 727174243 740810752 0 740810752 1 0 34437 34437
[1] https://github.com/lz4/lz4/issues/557
Link: https://lkml.kernel.org/r/20240902105656.1383858-21-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Immutable params never change once comp has been allocated and setup, so
we don't need to store multiple copies of them in each per-CPU backend
context. Move those to per-comp zcomp_params and pass it to backends
callbacks for requests execution. Basically, this means parameters
sharing between different contexts.
Also introduce two new backends callbacks: setup_params() and
release_params(). First, we need to validate params in a driver-specific
way; second, driver may want to allocate its specific representation of
the params which is needed to execute requests.
Link: https://lkml.kernel.org/r/20240902105656.1383858-20-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Keep run-time driver data (scratch buffers, etc.) in zcomp_ctx structure.
This structure is allocated per-CPU because drivers (backends) need to
modify its content during requests execution.
We will split mutable and immutable driver data, this is a preparation
path.
Link: https://lkml.kernel.org/r/20240902105656.1383858-19-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Encapsulate compression/decompression data in zcomp_req structure.
Link: https://lkml.kernel.org/r/20240902105656.1383858-18-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We will store a per-algorithm parameters there (compression level,
dictionary, dictionary size, etc.).
Link: https://lkml.kernel.org/r/20240902105656.1383858-14-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
