staging: android: persistent_ram: Move to fs/pstore/ram_core.c

This is a first step for adding ECC support for pstore RAM backend: we
will use the persistent_ram routines, kindly provided by Google.

Basically, persistent_ram is a set of helper routines to deal with the
[optionally] ECC-protected persistent ram regions.

A bit of Makefile, Kconfig and header files adjustments were needed
because of the move.

Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/staging/android/Kconfig

Change-Id: I2cb1494fb90fc844cdea2a0a77c55449e5d0a215

drivers/staging/android/Kconfig

@@ -33,17 +33,9 @@ config LOGCAT_SIZE
 	  Set logger buffer size. Enter a number greater than zero.
 	  Any value less than 256 is recommended. Reduce value to save kernel static memory size.
 
-config ANDROID_PERSISTENT_RAM
-	bool
-	depends on HAVE_MEMBLOCK
-	select REED_SOLOMON
-	select REED_SOLOMON_ENC8
-	select REED_SOLOMON_DEC8
-
 config ANDROID_RAM_CONSOLE
 	bool "Android RAM buffer console"
-	depends on !S390 && !UML && HAVE_MEMBLOCK
-	select ANDROID_PERSISTENT_RAM
+	depends on !S390 && !UML && HAVE_MEMBLOCK && PSTORE_RAM=y
 	default n
 
 config PERSISTENT_TRACER

drivers/staging/android/Makefile

@@ -3,7 +3,6 @@ ccflags-y += -I$(src)			# needed for trace events
 obj-$(CONFIG_ANDROID_BINDER_IPC)	+= binder.o
 obj-$(CONFIG_ASHMEM)			+= ashmem.o
 obj-$(CONFIG_ANDROID_LOGGER)		+= logger.o
-obj-$(CONFIG_ANDROID_PERSISTENT_RAM)	+= persistent_ram.o
 obj-$(CONFIG_ANDROID_RAM_CONSOLE)	+= ram_console.o
 obj-$(CONFIG_ANDROID_TIMED_OUTPUT)	+= timed_output.o
 obj-$(CONFIG_ANDROID_TIMED_GPIO)	+= timed_gpio.o

drivers/staging/android/ram_console.c

@@ -21,7 +21,7 @@
 #include <linux/string.h>
 #include <linux/uaccess.h>
 #include <linux/io.h>
-#include "persistent_ram.h"
+#include <linux/pstore_ram.h>
 #include "ram_console.h"
 
 static struct persistent_ram_zone *ram_console_zone;

fs/pstore/Kconfig

@@ -14,9 +14,12 @@ config PSTORE
 
 config PSTORE_RAM
 	tristate "Log panic/oops to a RAM buffer"
-	depends on HAS_IOMEM
 	depends on PSTORE
-	default n
+	depends on HAS_IOMEM
+	depends on HAVE_MEMBLOCK
+	select REED_SOLOMON
+	select REED_SOLOMON_ENC8
+	select REED_SOLOMON_DEC8
 	help
 	  This enables panic and oops messages to be logged to a circular
 	  buffer in RAM where it can be read back at some later point.

fs/pstore/Makefile

@@ -6,5 +6,5 @@ obj-y += pstore.o
 
 pstore-objs += inode.o platform.o
 
-ramoops-objs += ram.o
+ramoops-objs += ram.o ram_core.o
 obj-$(CONFIG_PSTORE_RAM)	+= ramoops.o

drivers/staging/android/persistent_ram.c → fs/pstore/ram_core.c

@@ -23,8 +23,8 @@
 #include <linux/rslib.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
+#include <linux/pstore_ram.h>
 #include <asm/page.h>
-#include "persistent_ram.h"
 
 struct persistent_ram_buffer {
 	uint32_t    sig;

include/linux/pstore_ram.h

@@ -1,6 +1,86 @@
+/*
+ * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
+ * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
 #ifndef __LINUX_PSTORE_RAM_H__
 #define __LINUX_PSTORE_RAM_H__
 
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/types.h>
+#include <linux/init.h>
+
+struct persistent_ram_buffer;
+
+struct persistent_ram_descriptor {
+	const char	*name;
+	phys_addr_t	size;
+};
+
+struct persistent_ram {
+	phys_addr_t	start;
+	phys_addr_t	size;
+
+	int					num_descs;
+	struct persistent_ram_descriptor	*descs;
+
+	struct list_head node;
+};
+
+struct persistent_ram_zone {
+	phys_addr_t paddr;
+	size_t size;
+	void *vaddr;
+	struct persistent_ram_buffer *buffer;
+	size_t buffer_size;
+
+	/* ECC correction */
+	bool ecc;
+	char *par_buffer;
+	char *par_header;
+	struct rs_control *rs_decoder;
+	int corrected_bytes;
+	int bad_blocks;
+	int ecc_block_size;
+	int ecc_size;
+	int ecc_symsize;
+	int ecc_poly;
+
+	char *old_log;
+	size_t old_log_size;
+};
+
+int persistent_ram_early_init(struct persistent_ram *ram);
+
+struct persistent_ram_zone * __init persistent_ram_new(phys_addr_t start,
+						       size_t size,
+						       bool ecc);
+void persistent_ram_free(struct persistent_ram_zone *prz);
+struct persistent_ram_zone *persistent_ram_init_ringbuffer(struct device *dev,
+		bool ecc);
+
+int persistent_ram_write(struct persistent_ram_zone *prz, const void *s,
+	unsigned int count);
+
+size_t persistent_ram_old_size(struct persistent_ram_zone *prz);
+void *persistent_ram_old(struct persistent_ram_zone *prz);
+void persistent_ram_free_old(struct persistent_ram_zone *prz);
+ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz,
+	char *str, size_t len);
+
 /*
  * Ramoops platform data
  * @mem_size	memory size for ramoops