[PATCH] zram: break the strict dependency from lzo

[PATCH] zram: break the strict dependency from lzo

[Rui Salvaterra]

There's nothing special about zram and lzo. It works just fine without it, so
as long as at least one of the other supported compression algorithms is
selected.

Additionally, drop the explicit dependency from CRYPTO, as it's implied by the
selection of the algorithms themselves.

Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com>
---
 drivers/block/zram/Kconfig | 8 ++++++--
 drivers/block/zram/zcomp.c | 2 ++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig
index fe7a4b7d30cf..2641b86f8677 100644
--- a/drivers/block/zram/Kconfig
+++ b/drivers/block/zram/Kconfig
@@ -1,8 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 config ZRAM
 	tristate "Compressed RAM block device support"
-	depends on BLOCK && SYSFS && ZSMALLOC && CRYPTO
-	select CRYPTO_LZO
+	depends on BLOCK && SYSFS && ZSMALLOC
 	help
 	  Creates virtual block devices called /dev/zramX (X = 0, 1, ...).
 	  Pages written to these disks are compressed and stored in memory
@@ -37,3 +36,8 @@ config ZRAM_MEMORY_TRACKING
 	  /sys/kernel/debug/zram/zramX/block_state.
 
 	  See Documentation/admin-guide/blockdev/zram.rst for more information.
+
+config ZRAM_AUTOSEL_ALGO
+	def_bool y
+	depends on ZRAM && !(CRYPTO_LZ4 || CRYPTO_LZ4HC || CRYPTO_842 || CRYPTO_ZSTD)
+	select CRYPTO_LZO
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index 33e3b76c4fa9..052aa3f65514 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -15,8 +15,10 @@
 #include "zcomp.h"
 
 static const char * const backends[] = {
+#if IS_ENABLED(CONFIG_CRYPTO_LZO)
 	"lzo",
 	"lzo-rle",
+#endif
 #if IS_ENABLED(CONFIG_CRYPTO_LZ4)
 	"lz4",
 #endif
-- 
2.28.0

Re: [PATCH] zram: break the strict dependency from lzo

[Rui Salvaterra]

Oops, this is broken, I'll send a v2 soon.

On Thu, 22 Oct 2020 at 17:11, Rui Salvaterra <rsalvaterra@gmail.com> wrote:
>
> There's nothing special about zram and lzo. It works just fine without it, so
> as long as at least one of the other supported compression algorithms is
> selected.
>
> Additionally, drop the explicit dependency from CRYPTO, as it's implied by the
> selection of the algorithms themselves.
>
> Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com>
> ---
>  drivers/block/zram/Kconfig | 8 ++++++--
>  drivers/block/zram/zcomp.c | 2 ++
>  2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig
> index fe7a4b7d30cf..2641b86f8677 100644
> --- a/drivers/block/zram/Kconfig
> +++ b/drivers/block/zram/Kconfig
> @@ -1,8 +1,7 @@
>  # SPDX-License-Identifier: GPL-2.0
>  config ZRAM
>         tristate "Compressed RAM block device support"
> -       depends on BLOCK && SYSFS && ZSMALLOC && CRYPTO
> -       select CRYPTO_LZO
> +       depends on BLOCK && SYSFS && ZSMALLOC
>         help
>           Creates virtual block devices called /dev/zramX (X = 0, 1, ...).
>           Pages written to these disks are compressed and stored in memory
> @@ -37,3 +36,8 @@ config ZRAM_MEMORY_TRACKING
>           /sys/kernel/debug/zram/zramX/block_state.
>
>           See Documentation/admin-guide/blockdev/zram.rst for more information.
> +
> +config ZRAM_AUTOSEL_ALGO
> +       def_bool y
> +       depends on ZRAM && !(CRYPTO_LZ4 || CRYPTO_LZ4HC || CRYPTO_842 || CRYPTO_ZSTD)
> +       select CRYPTO_LZO
> diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
> index 33e3b76c4fa9..052aa3f65514 100644
> --- a/drivers/block/zram/zcomp.c
> +++ b/drivers/block/zram/zcomp.c
> @@ -15,8 +15,10 @@
>  #include "zcomp.h"
>
>  static const char * const backends[] = {
> +#if IS_ENABLED(CONFIG_CRYPTO_LZO)
>         "lzo",
>         "lzo-rle",
> +#endif
>  #if IS_ENABLED(CONFIG_CRYPTO_LZ4)
>         "lz4",
>  #endif
> --
> 2.28.0
>