Merge tag 'pstore-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/ke…

…rnel/git/kees/linux

Pull pstore updates from Kees Cook:
 "This cycle was almost entirely improvements to the pstore compression
  options, noted below:

   - Add lz4hc and 842 to pstore compression options (Geliang Tang)

   - Refactor to use crypto compression API (Geliang Tang)

   - Fix up Kconfig dependencies for compression (Arnd Bergmann)

   - Allow for run-time compression selection

   - Remove stack VLA usage"

* tag 'pstore-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  pstore: fix crypto dependencies
  pstore: Use crypto compress API
  pstore/ram: Do not use stack VLA for parity workspace
  pstore: Select compression at runtime
  pstore: Avoid size casts for 842 compression
  pstore: Add lz4hc and 842 compression support

fs/pstore/Kconfig

@@ -1,5 +1,6 @@
 config PSTORE
 	tristate "Persistent store support"
+	select CRYPTO if PSTORE_COMPRESS
 	default n
 	help
 	   This option enables generic access to platform level
@@ -12,35 +13,89 @@ config PSTORE
 	   If you don't have a platform persistent store driver,
 	   say N.
 
-choice
-        prompt "Choose compression algorithm"
-        depends on PSTORE
-        default PSTORE_ZLIB_COMPRESS
-        help
-          This option chooses compression algorithm.
-
-config PSTORE_ZLIB_COMPRESS
-        bool "ZLIB"
-        select ZLIB_DEFLATE
-        select ZLIB_INFLATE
-        help
-          This option enables ZLIB compression algorithm support.
+config PSTORE_DEFLATE_COMPRESS
+	tristate "DEFLATE (ZLIB) compression"
+	default y
+	depends on PSTORE
+	select CRYPTO_DEFLATE
+	help
+	  This option enables DEFLATE (also known as ZLIB) compression
+	  algorithm support.
 
 config PSTORE_LZO_COMPRESS
-        bool "LZO"
-        select LZO_COMPRESS
-        select LZO_DECOMPRESS
-        help
-          This option enables LZO compression algorithm support.
+	tristate "LZO compression"
+	depends on PSTORE
+	select CRYPTO_LZO
+	help
+	  This option enables LZO compression algorithm support.
 
 config PSTORE_LZ4_COMPRESS
-        bool "LZ4"
-        select LZ4_COMPRESS
-        select LZ4_DECOMPRESS
-        help
-          This option enables LZ4 compression algorithm support.
+	tristate "LZ4 compression"
+	depends on PSTORE
+	select CRYPTO_LZ4
+	help
+	  This option enables LZ4 compression algorithm support.
+
+config PSTORE_LZ4HC_COMPRESS
+	tristate "LZ4HC compression"
+	depends on PSTORE
+	select CRYPTO_LZ4HC
+	help
+	  This option enables LZ4HC (high compression) mode algorithm.
+
+config PSTORE_842_COMPRESS
+	bool "842 compression"
+	depends on PSTORE
+	select CRYPTO_842
+	help
+	  This option enables 842 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
+
+choice
+	prompt "Default pstore compression algorithm"
+	depends on PSTORE_COMPRESS
+	help
+	  This option chooses the default active compression algorithm.
+	  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.
+
+	  The default compression algorithm is deflate.
+
+	config PSTORE_DEFLATE_COMPRESS_DEFAULT
+		bool "deflate" if PSTORE_DEFLATE_COMPRESS
+
+	config PSTORE_LZO_COMPRESS_DEFAULT
+		bool "lzo" if PSTORE_LZO_COMPRESS
+
+	config PSTORE_LZ4_COMPRESS_DEFAULT
+		bool "lz4" if PSTORE_LZ4_COMPRESS
+
+	config PSTORE_LZ4HC_COMPRESS_DEFAULT
+		bool "lz4hc" if PSTORE_LZ4HC_COMPRESS
+
+	config PSTORE_842_COMPRESS_DEFAULT
+		bool "842" if PSTORE_842_COMPRESS
+
 endchoice
 
+config PSTORE_COMPRESS_DEFAULT
+	string
+	depends on PSTORE_COMPRESS
+	default "deflate" if PSTORE_DEFLATE_COMPRESS_DEFAULT
+	default "lzo" if PSTORE_LZO_COMPRESS_DEFAULT
+	default "lz4" if PSTORE_LZ4_COMPRESS_DEFAULT
+	default "lz4hc" if PSTORE_LZ4HC_COMPRESS_DEFAULT
+	default "842" if PSTORE_842_COMPRESS_DEFAULT
+
 config PSTORE_CONSOLE
 	bool "Log kernel console messages"
 	depends on PSTORE

fs/pstore/inode.c

@@ -486,6 +486,8 @@ static int __init init_pstore_fs(void)
 {
 	int err;
 
+	pstore_choose_compression();
+
 	/* Create a convenient mount point for people to access pstore */
 	err = sysfs_create_mount_point(fs_kobj, "pstore");
 	if (err)

fs/pstore/internal.h

@@ -37,4 +37,7 @@ extern bool	pstore_is_mounted(void);
 extern void	pstore_record_init(struct pstore_record *record,
 				   struct pstore_info *psi);
 
+/* Called during module_init() */
+extern void __init pstore_choose_compression(void);
+
 #endif