Merge branch 'nvram' into next

arch/powerpc/include/asm/nvram.h

@@ -10,31 +10,7 @@
 #ifndef _ASM_POWERPC_NVRAM_H
 #define _ASM_POWERPC_NVRAM_H
 
-#include <linux/errno.h>
-
-#define NVRW_CNT 0x20
-#define NVRAM_HEADER_LEN 16 /* sizeof(struct nvram_header) */
-#define NVRAM_BLOCK_LEN 16
-#define NVRAM_MAX_REQ (2080/NVRAM_BLOCK_LEN)
-#define NVRAM_MIN_REQ (1056/NVRAM_BLOCK_LEN)
-
-#define NVRAM_AS0  0x74
-#define NVRAM_AS1  0x75
-#define NVRAM_DATA 0x77
-
-
-/* RTC Offsets */
-
-#define MOTO_RTC_SECONDS	0x1FF9
-#define MOTO_RTC_MINUTES	0x1FFA
-#define MOTO_RTC_HOURS		0x1FFB
-#define MOTO_RTC_DAY_OF_WEEK	0x1FFC
-#define MOTO_RTC_DAY_OF_MONTH	0x1FFD
-#define MOTO_RTC_MONTH		0x1FFE
-#define MOTO_RTC_YEAR		0x1FFF
-#define MOTO_RTC_CONTROLA       0x1FF8
-#define MOTO_RTC_CONTROLB       0x1FF9
-
+/* Signatures for nvram partitions */
 #define NVRAM_SIG_SP	0x02	/* support processor */
 #define NVRAM_SIG_OF	0x50	/* open firmware config */
 #define NVRAM_SIG_FW	0x51	/* general firmware */
@@ -49,32 +25,19 @@
 #define NVRAM_SIG_OS	0xa0	/* OS defined */
 #define NVRAM_SIG_PANIC	0xa1	/* Apple OSX "panic" */
 
-/* If change this size, then change the size of NVNAME_LEN */
-struct nvram_header {
-	unsigned char signature;
-	unsigned char checksum;
-	unsigned short length;
-	char name[12];
-};
-
 #ifdef __KERNEL__
 
+#include <linux/errno.h>
 #include <linux/list.h>
 
-struct nvram_partition {
-	struct list_head partition;
-	struct nvram_header header;
-	unsigned int index;
-};
-
-
+#ifdef CONFIG_PPC_PSERIES
 extern int nvram_write_error_log(char * buff, int length,
 					 unsigned int err_type, unsigned int err_seq);
 extern int nvram_read_error_log(char * buff, int length,
 					 unsigned int * err_type, unsigned int *err_seq);
 extern int nvram_clear_error_log(void);
-
 extern int pSeries_nvram_init(void);
+#endif /* CONFIG_PPC_PSERIES */
 
 #ifdef CONFIG_MMIO_NVRAM
 extern int mmio_nvram_init(void);
@@ -85,6 +48,13 @@ static inline int mmio_nvram_init(void)
 }
 #endif
 
+extern int __init nvram_scan_partitions(void);
+extern loff_t nvram_create_partition(const char *name, int sig,
+				     int req_size, int min_size);
+extern int nvram_remove_partition(const char *name, int sig);
+extern int nvram_get_partition_size(loff_t data_index);
+extern loff_t nvram_find_partition(const char *name, int sig, int *out_size);
+
 #endif /* __KERNEL__ */
 
 /* PowerMac specific nvram stuffs */

arch/powerpc/kernel/nvram_64.c

@@ -34,15 +34,26 @@
 
 #undef DEBUG_NVRAM
 
-static struct nvram_partition * nvram_part;
-static long nvram_error_log_index = -1;
-static long nvram_error_log_size = 0;
+#define NVRAM_HEADER_LEN	sizeof(struct nvram_header)
+#define NVRAM_BLOCK_LEN		NVRAM_HEADER_LEN
+
+/* If change this size, then change the size of NVNAME_LEN */
+struct nvram_header {
+	unsigned char signature;
+	unsigned char checksum;
+	unsigned short length;
+	/* Terminating null required only for names < 12 chars. */
+	char name[12];
+};
 
-struct err_log_info {
-	int error_type;
-	unsigned int seq_num;
+struct nvram_partition {
+	struct list_head partition;
+	struct nvram_header header;
+	unsigned int index;
 };
 
+static LIST_HEAD(nvram_partitions);
+
 static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin)
 {
 	int size;
@@ -186,14 +197,12 @@ static struct miscdevice nvram_dev = {
 #ifdef DEBUG_NVRAM
 static void __init nvram_print_partitions(char * label)
 {
-	struct list_head * p;
 	struct nvram_partition * tmp_part;
 	
 	printk(KERN_WARNING "--------%s---------\n", label);
 	printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n");
-	list_for_each(p, &nvram_part->partition) {
-		tmp_part = list_entry(p, struct nvram_partition, partition);
-		printk(KERN_WARNING "%4d    \t%02x\t%02x\t%d\t%s\n",
+	list_for_each_entry(tmp_part, &nvram_partitions, partition) {
+		printk(KERN_WARNING "%4d    \t%02x\t%02x\t%d\t%12s\n",
 		       tmp_part->index, tmp_part->header.signature,
 		       tmp_part->header.checksum, tmp_part->header.length,
 		       tmp_part->header.name);
@@ -228,95 +237,113 @@ static unsigned char __init nvram_checksum(struct nvram_header *p)
 	return c_sum;
 }
 
-static int __init nvram_remove_os_partition(void)
+/**
+ * nvram_remove_partition - Remove one or more partitions in nvram
+ * @name: name of the partition to remove, or NULL for a
+ *        signature only match
+ * @sig: signature of the partition(s) to remove
+ */
+
+int __init nvram_remove_partition(const char *name, int sig)
 {
-	struct list_head *i;
-	struct list_head *j;
-	struct nvram_partition * part;
-	struct nvram_partition * cur_part;
+	struct nvram_partition *part, *prev, *tmp;
 	int rc;
 
-	list_for_each(i, &nvram_part->partition) {
-		part = list_entry(i, struct nvram_partition, partition);
-		if (part->header.signature != NVRAM_SIG_OS)
+	list_for_each_entry(part, &nvram_partitions, partition) {
+		if (part->header.signature != sig)
 			continue;
-		
-		/* Make os partition a free partition */
+		if (name && strncmp(name, part->header.name, 12))
+			continue;
+
+		/* Make partition a free partition */
 		part->header.signature = NVRAM_SIG_FREE;
-		sprintf(part->header.name, "wwwwwwwwwwww");
+		strncpy(part->header.name, "wwwwwwwwwwww", 12);
 		part->header.checksum = nvram_checksum(&part->header);
-
-		/* Merge contiguous free partitions backwards */
-		list_for_each_prev(j, &part->partition) {
-			cur_part = list_entry(j, struct nvram_partition, partition);
-			if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) {
-				break;
-			}
-			
-			part->header.length += cur_part->header.length;
-			part->header.checksum = nvram_checksum(&part->header);
-			part->index = cur_part->index;
-
-			list_del(&cur_part->partition);
-			kfree(cur_part);
-			j = &part->partition; /* fixup our loop */
-		}
-		
-		/* Merge contiguous free partitions forwards */
-		list_for_each(j, &part->partition) {
-			cur_part = list_entry(j, struct nvram_partition, partition);
-			if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) {
-				break;
-			}
-
-			part->header.length += cur_part->header.length;
-			part->header.checksum = nvram_checksum(&part->header);
-
-			list_del(&cur_part->partition);
-			kfree(cur_part);
-			j = &part->partition; /* fixup our loop */
-		}
-		
 		rc = nvram_write_header(part);
 		if (rc <= 0) {
-			printk(KERN_ERR "nvram_remove_os_partition: nvram_write failed (%d)\n", rc);
+			printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc);
 			return rc;
 		}
+	}
 
+	/* Merge contiguous ones */
+	prev = NULL;
+	list_for_each_entry_safe(part, tmp, &nvram_partitions, partition) {
+		if (part->header.signature != NVRAM_SIG_FREE) {
+			prev = NULL;
+			continue;
+		}
+		if (prev) {
+			prev->header.length += part->header.length;
+			prev->header.checksum = nvram_checksum(&part->header);
+			rc = nvram_write_header(part);
+			if (rc <= 0) {
+				printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc);
+				return rc;
+			}
+			list_del(&part->partition);
+			kfree(part);
+		} else
+			prev = part;
 	}
 	
 	return 0;
 }
 
-/* nvram_create_os_partition
+/**
+ * nvram_create_partition - Create a partition in nvram
+ * @name: name of the partition to create
+ * @sig: signature of the partition to create
+ * @req_size: size of data to allocate in bytes
+ * @min_size: minimum acceptable size (0 means req_size)
  *
- * Create a OS linux partition to buffer error logs.
- * Will create a partition starting at the first free
- * space found if space has enough room.
+ * Returns a negative error code or a positive nvram index
+ * of the beginning of the data area of the newly created
+ * partition. If you provided a min_size smaller than req_size
+ * you need to query for the actual size yourself after the
+ * call using nvram_partition_get_size().
  */
-static int __init nvram_create_os_partition(void)
+loff_t __init nvram_create_partition(const char *name, int sig,
+				     int req_size, int min_size)
 {
 	struct nvram_partition *part;
 	struct nvram_partition *new_part;
 	struct nvram_partition *free_part = NULL;
-	int seq_init[2] = { 0, 0 };
+	static char nv_init_vals[16];
 	loff_t tmp_index;
 	long size = 0;
 	int rc;
-	
+
+	/* Convert sizes from bytes to blocks */
+	req_size = _ALIGN_UP(req_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN;
+	min_size = _ALIGN_UP(min_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN;
+
+	/* If no minimum size specified, make it the same as the
+	 * requested size
+	 */
+	if (min_size == 0)
+		min_size = req_size;
+	if (min_size > req_size)
+		return -EINVAL;
+
+	/* Now add one block to each for the header */
+	req_size += 1;
+	min_size += 1;
+
 	/* Find a free partition that will give us the maximum needed size 
 	   If can't find one that will give us the minimum size needed */
-	list_for_each_entry(part, &nvram_part->partition, partition) {
+	list_for_each_entry(part, &nvram_partitions, partition) {
 		if (part->header.signature != NVRAM_SIG_FREE)
 			continue;
 
-		if (part->header.length >= NVRAM_MAX_REQ) {
-			size = NVRAM_MAX_REQ;
+		if (part->header.length >= req_size) {
+			size = req_size;
 			free_part = part;
 			break;
 		}
-		if (!size && part->header.length >= NVRAM_MIN_REQ) {
-			size = NVRAM_MIN_REQ;
+		if (part->header.length > size &&
+		    part->header.length >= min_size) {
+			size = part->header.length;
 			free_part = part;
 		}
 	}
@@ -326,136 +353,95 @@ static int __init nvram_create_os_partition(void)
 	/* Create our OS partition */
 	new_part = kmalloc(sizeof(*new_part), GFP_KERNEL);
 	if (!new_part) {
-		printk(KERN_ERR "nvram_create_os_partition: kmalloc failed\n");
+		pr_err("nvram_create_os_partition: kmalloc failed\n");
 		return -ENOMEM;
 	}
 
 	new_part->index = free_part->index;
-	new_part->header.signature = NVRAM_SIG_OS;
+	new_part->header.signature = sig;
 	new_part->header.length = size;
-	strcpy(new_part->header.name, "ppc64,linux");
+	strncpy(new_part->header.name, name, 12);
 	new_part->header.checksum = nvram_checksum(&new_part->header);
 
 	rc = nvram_write_header(new_part);
 	if (rc <= 0) {
-		printk(KERN_ERR "nvram_create_os_partition: nvram_write_header "
-				"failed (%d)\n", rc);
-		return rc;
-	}
-
-	/* make sure and initialize to zero the sequence number and the error
-	   type logged */
-	tmp_index = new_part->index + NVRAM_HEADER_LEN;
-	rc = ppc_md.nvram_write((char *)&seq_init, sizeof(seq_init), &tmp_index);
-	if (rc <= 0) {
-		printk(KERN_ERR "nvram_create_os_partition: nvram_write "
+		pr_err("nvram_create_os_partition: nvram_write_header "
 		       "failed (%d)\n", rc);
 		return rc;
 	}
-	
-	nvram_error_log_index = new_part->index + NVRAM_HEADER_LEN;
-	nvram_error_log_size = ((part->header.length - 1) *
-				NVRAM_BLOCK_LEN) - sizeof(struct err_log_info);
-	
 	list_add_tail(&new_part->partition, &free_part->partition);
 
-	if (free_part->header.length <= size) {
+	/* Adjust or remove the partition we stole the space from */
+	if (free_part->header.length > size) {
+		free_part->index += size * NVRAM_BLOCK_LEN;
+		free_part->header.length -= size;
+		free_part->header.checksum = nvram_checksum(&free_part->header);
+		rc = nvram_write_header(free_part);
+		if (rc <= 0) {
+			pr_err("nvram_create_os_partition: nvram_write_header "
+			       "failed (%d)\n", rc);
+			return rc;
+		}
+	} else {
 		list_del(&free_part->partition);
 		kfree(free_part);
-		return 0;
 	} 
 
-	/* Adjust the partition we stole the space from */
-	free_part->index += size * NVRAM_BLOCK_LEN;
-	free_part->header.length -= size;
-	free_part->header.checksum = nvram_checksum(&free_part->header);
-	
-	rc = nvram_write_header(free_part);
-	if (rc <= 0) {
-		printk(KERN_ERR "nvram_create_os_partition: nvram_write_header "
-		       "failed (%d)\n", rc);
-		return rc;
+	/* Clear the new partition */
+	for (tmp_index = new_part->index + NVRAM_HEADER_LEN;
+	     tmp_index <  ((size - 1) * NVRAM_BLOCK_LEN);
+	     tmp_index += NVRAM_BLOCK_LEN) {
+		rc = ppc_md.nvram_write(nv_init_vals, NVRAM_BLOCK_LEN, &tmp_index);
+		if (rc <= 0) {
+			pr_err("nvram_create_partition: nvram_write failed (%d)\n", rc);
+			return rc;
+		}
 	}
-
-	return 0;
+	
+	return new_part->index + NVRAM_HEADER_LEN;
 }
 
-
-/* nvram_setup_partition
- *
- * This will setup the partition we need for buffering the
- * error logs and cleanup partitions if needed.
- *
- * The general strategy is the following:
- * 1.) If there is ppc64,linux partition large enough then use it.
- * 2.) If there is not a ppc64,linux partition large enough, search
- * for a free partition that is large enough.
- * 3.) If there is not a free partition large enough remove 
- * _all_ OS partitions and consolidate the space.
- * 4.) Will first try getting a chunk that will satisfy the maximum
- * error log size (NVRAM_MAX_REQ).
- * 5.) If the max chunk cannot be allocated then try finding a chunk
- * that will satisfy the minum needed (NVRAM_MIN_REQ).
+/**
+ * nvram_get_partition_size - Get the data size of an nvram partition
+ * @data_index: This is the offset of the start of the data of
+ *              the partition. The same value that is returned by
+ *              nvram_create_partition().
  */
-static int __init nvram_setup_partition(void)
+int nvram_get_partition_size(loff_t data_index)
 {
-	struct list_head * p;
-	struct nvram_partition * part;
-	int rc;
-
-	/* For now, we don't do any of this on pmac, until I
-	 * have figured out if it's worth killing some unused stuffs
-	 * in our nvram, as Apple defined partitions use pretty much
-	 * all of the space
-	 */
-	if (machine_is(powermac))
-		return -ENOSPC;
-
-	/* see if we have an OS partition that meets our needs.
-	   will try getting the max we need.  If not we'll delete
-	   partitions and try again. */
-	list_for_each(p, &nvram_part->partition) {
-		part = list_entry(p, struct nvram_partition, partition);
-		if (part->header.signature != NVRAM_SIG_OS)
-			continue;
+	struct nvram_partition *part;
+	
+	list_for_each_entry(part, &nvram_partitions, partition) {
+		if (part->index + NVRAM_HEADER_LEN == data_index)
+			return (part->header.length - 1) * NVRAM_BLOCK_LEN;
+	}
+	return -1;
+}
 
-		if (strcmp(part->header.name, "ppc64,linux"))
-			continue;
 
-		if (part->header.length >= NVRAM_MIN_REQ) {
-			/* found our partition */
-			nvram_error_log_index = part->index + NVRAM_HEADER_LEN;
-			nvram_error_log_size = ((part->header.length - 1) *
-						NVRAM_BLOCK_LEN) - sizeof(struct err_log_info);
-			return 0;
+/**
+ * nvram_find_partition - Find an nvram partition by signature and name
+ * @name: Name of the partition or NULL for any name
+ * @sig: Signature to test against
+ * @out_size: if non-NULL, returns the size of the data part of the partition
+ */
+loff_t nvram_find_partition(const char *name, int sig, int *out_size)
+{
+	struct nvram_partition *p;
+
+	list_for_each_entry(p, &nvram_partitions, partition) {
+		if (p->header.signature == sig &&
+		    (!name || !strncmp(p->header.name, name, 12))) {
+			if (out_size)
+				*out_size = (p->header.length - 1) *
+					NVRAM_BLOCK_LEN;
+			return p->index + NVRAM_HEADER_LEN;
 		}
 	}
-	
-	/* try creating a partition with the free space we have */
-	rc = nvram_create_os_partition();
-	if (!rc) {
-		return 0;
-	}
-		
-	/* need to free up some space */
-	rc = nvram_remove_os_partition();
-	if (rc) {
-		return rc;
-	}
-	
-	/* create a partition in this new space */
-	rc = nvram_create_os_partition();
-	if (rc) {
-		printk(KERN_ERR "nvram_create_os_partition: Could not find a "
-		       "NVRAM partition large enough\n");
-		return rc;
-	}
-	
 	return 0;
 }
 
-
-static int __init nvram_scan_partitions(void)
+int __init nvram_scan_partitions(void)
 {
 	loff_t cur_index = 0;
 	struct nvram_header phead;
@@ -465,7 +451,7 @@ static int __init nvram_scan_partitions(void)
 	int total_size;
 	int err;
 
-	if (ppc_md.nvram_size == NULL)
+	if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0)
 		return -ENODEV;
 	total_size = ppc_md.nvram_size();
 	
@@ -512,12 +498,16 @@ static int __init nvram_scan_partitions(void)
 		
 		memcpy(&tmp_part->header, &phead, NVRAM_HEADER_LEN);
 		tmp_part->index = cur_index;
-		list_add_tail(&tmp_part->partition, &nvram_part->partition);
+		list_add_tail(&tmp_part->partition, &nvram_partitions);
 		
 		cur_index += phead.length * NVRAM_BLOCK_LEN;
 	}
 	err = 0;
 
+#ifdef DEBUG_NVRAM
+	nvram_print_partitions("NVRAM Partitions");
+#endif
+
  out:
 	kfree(header);
 	return err;
@@ -525,9 +515,10 @@ static int __init nvram_scan_partitions(void)
 
 static int __init nvram_init(void)
 {
-	int error;
 	int rc;
 	
+	BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16);
+
 	if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0)
 		return  -ENODEV;
 
@@ -537,29 +528,6 @@ static int __init nvram_init(void)
 		return rc;
 	}
   	
-  	/* initialize our anchor for the nvram partition list */
-  	nvram_part = kmalloc(sizeof(struct nvram_partition), GFP_KERNEL);
-  	if (!nvram_part) {
-  		printk(KERN_ERR "nvram_init: Failed kmalloc\n");
-  		return -ENOMEM;
-  	}
-  	INIT_LIST_HEAD(&nvram_part->partition);
-  
-  	/* Get all the NVRAM partitions */
-  	error = nvram_scan_partitions();
-  	if (error) {
-  		printk(KERN_ERR "nvram_init: Failed nvram_scan_partitions\n");
-  		return error;
-  	}
-  		
-  	if(nvram_setup_partition()) 
-  		printk(KERN_WARNING "nvram_init: Could not find nvram partition"
-  		       " for nvram buffered error logging.\n");
-  
-#ifdef DEBUG_NVRAM
-	nvram_print_partitions("NVRAM Partitions");
-#endif
-
   	return rc;
 }
 
@@ -568,135 +536,6 @@ void __exit nvram_cleanup(void)
         misc_deregister( &nvram_dev );
 }
 
-
-#ifdef CONFIG_PPC_PSERIES
-
-/* nvram_write_error_log
- *
- * We need to buffer the error logs into nvram to ensure that we have
- * the failure information to decode.  If we have a severe error there
- * is no way to guarantee that the OS or the machine is in a state to
- * get back to user land and write the error to disk.  For example if
- * the SCSI device driver causes a Machine Check by writing to a bad
- * IO address, there is no way of guaranteeing that the device driver
- * is in any state that is would also be able to write the error data
- * captured to disk, thus we buffer it in NVRAM for analysis on the
- * next boot.
- *
- * In NVRAM the partition containing the error log buffer will looks like:
- * Header (in bytes):
- * +-----------+----------+--------+------------+------------------+
- * | signature | checksum | length | name       | data             |
- * |0          |1         |2      3|4         15|16        length-1|
- * +-----------+----------+--------+------------+------------------+
- *
- * The 'data' section would look like (in bytes):
- * +--------------+------------+-----------------------------------+
- * | event_logged | sequence # | error log                         |
- * |0            3|4          7|8            nvram_error_log_size-1|
- * +--------------+------------+-----------------------------------+
- *
- * event_logged: 0 if event has not been logged to syslog, 1 if it has
- * sequence #: The unique sequence # for each event. (until it wraps)
- * error log: The error log from event_scan
- */
-int nvram_write_error_log(char * buff, int length,
-                          unsigned int err_type, unsigned int error_log_cnt)
-{
-	int rc;
-	loff_t tmp_index;
-	struct err_log_info info;
-	
-	if (nvram_error_log_index == -1) {
-		return -ESPIPE;
-	}
-
-	if (length > nvram_error_log_size) {
-		length = nvram_error_log_size;
-	}
-
-	info.error_type = err_type;
-	info.seq_num = error_log_cnt;
-
-	tmp_index = nvram_error_log_index;
-
-	rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), &tmp_index);
-	if (rc <= 0) {
-		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
-		return rc;
-	}
-
-	rc = ppc_md.nvram_write(buff, length, &tmp_index);
-	if (rc <= 0) {
-		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
-		return rc;
-	}
-	
-	return 0;
-}
-
-/* nvram_read_error_log
- *
- * Reads nvram for error log for at most 'length'
- */
-int nvram_read_error_log(char * buff, int length,
-                         unsigned int * err_type, unsigned int * error_log_cnt)
-{
-	int rc;
-	loff_t tmp_index;
-	struct err_log_info info;
-	
-	if (nvram_error_log_index == -1)
-		return -1;
-
-	if (length > nvram_error_log_size)
-		length = nvram_error_log_size;
-
-	tmp_index = nvram_error_log_index;
-
-	rc = ppc_md.nvram_read((char *)&info, sizeof(struct err_log_info), &tmp_index);
-	if (rc <= 0) {
-		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
-		return rc;
-	}
-
-	rc = ppc_md.nvram_read(buff, length, &tmp_index);
-	if (rc <= 0) {
-		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
-		return rc;
-	}
-
-	*error_log_cnt = info.seq_num;
-	*err_type = info.error_type;
-
-	return 0;
-}
-
-/* This doesn't actually zero anything, but it sets the event_logged
- * word to tell that this event is safely in syslog.
- */
-int nvram_clear_error_log(void)
-{
-	loff_t tmp_index;
-	int clear_word = ERR_FLAG_ALREADY_LOGGED;
-	int rc;
-
-	if (nvram_error_log_index == -1)
-		return -1;
-
-	tmp_index = nvram_error_log_index;
-	
-	rc = ppc_md.nvram_write((char *)&clear_word, sizeof(int), &tmp_index);
-	if (rc <= 0) {
-		printk(KERN_ERR "nvram_clear_error_log: Failed nvram_write (%d)\n", rc);
-		return rc;
-	}
-
-	return 0;
-}
-
-#endif /* CONFIG_PPC_PSERIES */
-
 module_init(nvram_init);
 module_exit(nvram_cleanup);
 MODULE_LICENSE("GPL");

arch/powerpc/mm/pgtable.c

@@ -92,7 +92,7 @@ static void pte_free_rcu_callback(struct rcu_head *head)
 
 static void pte_free_submit(struct pte_freelist_batch *batch)
 {
-	call_rcu(&batch->rcu, pte_free_rcu_callback);
+	call_rcu_sched(&batch->rcu, pte_free_rcu_callback);
 }
 
 void pgtable_free_tlb(struct mmu_gather *tlb, void *table, unsigned shift)

arch/powerpc/platforms/chrp/time.c

@@ -29,6 +29,10 @@
 
 extern spinlock_t rtc_lock;
 
+#define NVRAM_AS0  0x74
+#define NVRAM_AS1  0x75
+#define NVRAM_DATA 0x77
+
 static int nvram_as1 = NVRAM_AS1;
 static int nvram_as0 = NVRAM_AS0;
 static int nvram_data = NVRAM_DATA;

arch/powerpc/platforms/pseries/nvram.c

@@ -22,11 +22,25 @@
 #include <asm/prom.h>
 #include <asm/machdep.h>
 
+/* Max bytes to read/write in one go */
+#define NVRW_CNT 0x20
+
 static unsigned int nvram_size;
 static int nvram_fetch, nvram_store;
 static char nvram_buf[NVRW_CNT];	/* assume this is in the first 4GB */
 static DEFINE_SPINLOCK(nvram_lock);
 
+static long nvram_error_log_index = -1;
+static long nvram_error_log_size = 0;
+
+struct err_log_info {
+	int error_type;
+	unsigned int seq_num;
+};
+#define NVRAM_MAX_REQ		2079
+#define NVRAM_MIN_REQ		1055
+
+#define NVRAM_LOG_PART_NAME	"ibm,rtas-log"
 
 static ssize_t pSeries_nvram_read(char *buf, size_t count, loff_t *index)
 {
@@ -119,6 +133,197 @@ static ssize_t pSeries_nvram_get_size(void)
 	return nvram_size ? nvram_size : -ENODEV;
 }
 
+
+/* nvram_write_error_log
+ *
+ * We need to buffer the error logs into nvram to ensure that we have
+ * the failure information to decode.  If we have a severe error there
+ * is no way to guarantee that the OS or the machine is in a state to
+ * get back to user land and write the error to disk.  For example if
+ * the SCSI device driver causes a Machine Check by writing to a bad
+ * IO address, there is no way of guaranteeing that the device driver
+ * is in any state that is would also be able to write the error data
+ * captured to disk, thus we buffer it in NVRAM for analysis on the
+ * next boot.
+ *
+ * In NVRAM the partition containing the error log buffer will looks like:
+ * Header (in bytes):
+ * +-----------+----------+--------+------------+------------------+
+ * | signature | checksum | length | name       | data             |
+ * |0          |1         |2      3|4         15|16        length-1|
+ * +-----------+----------+--------+------------+------------------+
+ *
+ * The 'data' section would look like (in bytes):
+ * +--------------+------------+-----------------------------------+
+ * | event_logged | sequence # | error log                         |
+ * |0            3|4          7|8            nvram_error_log_size-1|
+ * +--------------+------------+-----------------------------------+
+ *
+ * event_logged: 0 if event has not been logged to syslog, 1 if it has
+ * sequence #: The unique sequence # for each event. (until it wraps)
+ * error log: The error log from event_scan
+ */
+int nvram_write_error_log(char * buff, int length,
+                          unsigned int err_type, unsigned int error_log_cnt)
+{
+	int rc;
+	loff_t tmp_index;
+	struct err_log_info info;
+	
+	if (nvram_error_log_index == -1) {
+		return -ESPIPE;
+	}
+
+	if (length > nvram_error_log_size) {
+		length = nvram_error_log_size;
+	}
+
+	info.error_type = err_type;
+	info.seq_num = error_log_cnt;
+
+	tmp_index = nvram_error_log_index;
+
+	rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
+		return rc;
+	}
+
+	rc = ppc_md.nvram_write(buff, length, &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
+		return rc;
+	}
+	
+	return 0;
+}
+
+/* nvram_read_error_log
+ *
+ * Reads nvram for error log for at most 'length'
+ */
+int nvram_read_error_log(char * buff, int length,
+                         unsigned int * err_type, unsigned int * error_log_cnt)
+{
+	int rc;
+	loff_t tmp_index;
+	struct err_log_info info;
+	
+	if (nvram_error_log_index == -1)
+		return -1;
+
+	if (length > nvram_error_log_size)
+		length = nvram_error_log_size;
+
+	tmp_index = nvram_error_log_index;
+
+	rc = ppc_md.nvram_read((char *)&info, sizeof(struct err_log_info), &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
+		return rc;
+	}
+
+	rc = ppc_md.nvram_read(buff, length, &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
+		return rc;
+	}
+
+	*error_log_cnt = info.seq_num;
+	*err_type = info.error_type;
+
+	return 0;
+}
+
+/* This doesn't actually zero anything, but it sets the event_logged
+ * word to tell that this event is safely in syslog.
+ */
+int nvram_clear_error_log(void)
+{
+	loff_t tmp_index;
+	int clear_word = ERR_FLAG_ALREADY_LOGGED;
+	int rc;
+
+	if (nvram_error_log_index == -1)
+		return -1;
+
+	tmp_index = nvram_error_log_index;
+	
+	rc = ppc_md.nvram_write((char *)&clear_word, sizeof(int), &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_clear_error_log: Failed nvram_write (%d)\n", rc);
+		return rc;
+	}
+
+	return 0;
+}
+
+/* pseries_nvram_init_log_partition
+ *
+ * This will setup the partition we need for buffering the
+ * error logs and cleanup partitions if needed.
+ *
+ * The general strategy is the following:
+ * 1.) If there is log partition large enough then use it.
+ * 2.) If there is none large enough, search
+ * for a free partition that is large enough.
+ * 3.) If there is not a free partition large enough remove 
+ * _all_ OS partitions and consolidate the space.
+ * 4.) Will first try getting a chunk that will satisfy the maximum
+ * error log size (NVRAM_MAX_REQ).
+ * 5.) If the max chunk cannot be allocated then try finding a chunk
+ * that will satisfy the minum needed (NVRAM_MIN_REQ).
+ */
+static int __init pseries_nvram_init_log_partition(void)
+{
+	loff_t p;
+	int size;
+
+	/* Scan nvram for partitions */
+	nvram_scan_partitions();
+
+	/* Lookg for ours */
+	p = nvram_find_partition(NVRAM_LOG_PART_NAME, NVRAM_SIG_OS, &size);
+
+	/* Found one but too small, remove it */
+	if (p && size < NVRAM_MIN_REQ) {
+		pr_info("nvram: Found too small "NVRAM_LOG_PART_NAME" partition"
+			",removing it...");
+		nvram_remove_partition(NVRAM_LOG_PART_NAME, NVRAM_SIG_OS);
+		p = 0;
+	}
+
+	/* Create one if we didn't find */
+	if (!p) {
+		p = nvram_create_partition(NVRAM_LOG_PART_NAME, NVRAM_SIG_OS,
+					   NVRAM_MAX_REQ, NVRAM_MIN_REQ);
+		/* No room for it, try to get rid of any OS partition
+		 * and try again
+		 */
+		if (p == -ENOSPC) {
+			pr_info("nvram: No room to create "NVRAM_LOG_PART_NAME
+				" partition, deleting all OS partitions...");
+			nvram_remove_partition(NULL, NVRAM_SIG_OS);
+			p = nvram_create_partition(NVRAM_LOG_PART_NAME,
+						   NVRAM_SIG_OS, NVRAM_MAX_REQ,
+						   NVRAM_MIN_REQ);
+		}
+	}
+
+	if (p <= 0) {
+		pr_err("nvram: Failed to find or create "NVRAM_LOG_PART_NAME
+		       " partition, err %d\n", (int)p);
+		return 0;
+	}
+
+	nvram_error_log_index = p;
+	nvram_error_log_size = nvram_get_partition_size(p) -
+		sizeof(struct err_log_info);
+	
+	return 0;
+}
+machine_arch_initcall(pseries, pseries_nvram_init_log_partition);
+
 int __init pSeries_nvram_init(void)
 {
 	struct device_node *nvram;