[PATCH] pstore: add zstd compression support

From: Geliang Tang
Date: Wed Mar 21 2018 - 08:29:45 EST


This patch added the 6th compression algorithm support for pstore: zstd.

Signed-off-by: Geliang Tang <geliangtang@xxxxxxxxx>
---
Depend on 'crypto: Add zstd support' by Nick Terrell <terrelln@xxxxxx>
---
fs/pstore/Kconfig | 17 ++++++++++++++---
fs/pstore/platform.c | 16 ++++++++++++++++
2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig
index 09c19ef91526..63cf4813559a 100644
--- a/fs/pstore/Kconfig
+++ b/fs/pstore/Kconfig
@@ -50,12 +50,19 @@ config PSTORE_842_COMPRESS
help
This option enables 842 compression algorithm support.

+config PSTORE_ZSTD_COMPRESS
+ tristate "zstd compression"
+ depends on PSTORE
+ select CRYPTO_ZSTD
+ help
+ This option enables zstd compression algorithm support.
+
config PSTORE_COMPRESS
def_bool y
depends on PSTORE
depends on PSTORE_DEFLATE_COMPRESS || PSTORE_LZO_COMPRESS || \
PSTORE_LZ4_COMPRESS || PSTORE_LZ4HC_COMPRESS || \
- PSTORE_842_COMPRESS
+ PSTORE_842_COMPRESS || PSTORE_ZSTD_COMPRESS

choice
prompt "Default pstore compression algorithm"
@@ -65,8 +72,8 @@ choice
This change be changed at boot with "pstore.compress=..." on
the kernel command line.

- Currently, pstore has support for 5 compression algorithms:
- deflate, lzo, lz4, lz4hc and 842.
+ Currently, pstore has support for 6 compression algorithms:
+ deflate, lzo, lz4, lz4hc, 842 and zstd.

The default compression algorithm is deflate.

@@ -85,6 +92,9 @@ choice
config PSTORE_842_COMPRESS_DEFAULT
bool "842" if PSTORE_842_COMPRESS

+ config PSTORE_ZSTD_COMPRESS_DEFAULT
+ bool "zstd" if PSTORE_ZSTD_COMPRESS
+
endchoice

config PSTORE_COMPRESS_DEFAULT
@@ -95,6 +105,7 @@ config PSTORE_COMPRESS_DEFAULT
default "lz4" if PSTORE_LZ4_COMPRESS_DEFAULT
default "lz4hc" if PSTORE_LZ4HC_COMPRESS_DEFAULT
default "842" if PSTORE_842_COMPRESS_DEFAULT
+ default "zstd" if PSTORE_ZSTD_COMPRESS_DEFAULT

config PSTORE_CONSOLE
bool "Log kernel console messages"
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 1143ef351c58..9df8cdc378f5 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -34,6 +34,9 @@
#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
#include <linux/lz4.h>
#endif
+#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
+#include <linux/zstd.h>
+#endif
#include <linux/crypto.h>
#include <linux/string.h>
#include <linux/timer.h>
@@ -192,6 +195,13 @@ static int zbufsize_842(size_t size)
}
#endif

+#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
+static int zbufsize_zstd(size_t size)
+{
+ return ZSTD_compressBound(size);
+}
+#endif
+
static const struct pstore_zbackend *zbackend __ro_after_init;

static const struct pstore_zbackend zbackends[] = {
@@ -224,6 +234,12 @@ static const struct pstore_zbackend zbackends[] = {
.zbufsize = zbufsize_842,
.name = "842",
},
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
+ {
+ .zbufsize = zbufsize_zstd,
+ .name = "zstd",
+ },
#endif
{ }
};
--
2.14.1