pstore: add zstd compression support

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

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig
index 09c19ef..503086f 100644 (file)
--- 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
+       bool "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 c238ab8..15e99d5 100644 (file)
--- 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[] = {
@@ -225,6 +235,12 @@ static const struct pstore_zbackend zbackends[] = {
                .name           = "842",
        },
 #endif
+#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
+       {
+               .zbufsize       = zbufsize_zstd,
+               .name           = "zstd",
+       },
+#endif
        { }
 };