1 files changed, 21 insertions, 9 deletions

diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c
index 1f4d8c06f9be..a89e33719fcf 100644
--- a/fs/pstore/ram_core.c
+++ b/fs/pstore/ram_core.c
@@ -34,7 +34,7 @@ struct persistent_ram_buffer {
 	uint32_t    sig;
 	atomic_t    start;
 	atomic_t    size;
-	uint8_t     data[0];
+	uint8_t     data[];
 };
 
 #define PERSISTENT_RAM_SIG (0x43474244) /* DBGC */
@@ -246,7 +246,7 @@ static int persistent_ram_init_ecc(struct persistent_ram_zone *prz,
 		pr_info("error in header, %d\n", numerr);
 		prz->corrected_bytes += numerr;
 	} else if (numerr < 0) {
-		pr_info("uncorrectable error in header\n");
+		pr_info_ratelimited("uncorrectable error in header\n");
 		prz->bad_blocks++;
 	}
 
@@ -263,10 +263,10 @@ ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz,
 
 	if (prz->corrected_bytes || prz->bad_blocks)
 		ret = snprintf(str, len, ""
-			"\n%d Corrected bytes, %d unrecoverable blocks\n",
+			"\nECC: %d Corrected bytes, %d unrecoverable blocks\n",
 			prz->corrected_bytes, prz->bad_blocks);
 	else
-		ret = snprintf(str, len, "\nNo errors detected\n");
+		ret = snprintf(str, len, "\nECC: No errors detected\n");
 
 	return ret;
 }
@@ -283,7 +283,7 @@ static int notrace persistent_ram_update_user(struct persistent_ram_zone *prz,
 	const void __user *s, unsigned int start, unsigned int count)
 {
 	struct persistent_ram_buffer *buffer = prz->buffer;
-	int ret = unlikely(__copy_from_user(buffer->data + start, s, count)) ?
+	int ret = unlikely(copy_from_user(buffer->data + start, s, count)) ?
 		-EFAULT : 0;
 	persistent_ram_update_ecc(prz, start, count);
 	return ret;
@@ -348,8 +348,6 @@ int notrace persistent_ram_write_user(struct persistent_ram_zone *prz,
 	int rem, ret = 0, c = count;
 	size_t start;
 
-	if (unlikely(!access_ok(s, count)))
-		return -EFAULT;
 	if (unlikely(c > prz->buffer_size)) {
 		s += c - prz->buffer_size;
 		c = prz->buffer_size;
@@ -398,6 +396,10 @@ void persistent_ram_zap(struct persistent_ram_zone *prz)
 	persistent_ram_update_header_ecc(prz);
 }
 
+#define MEM_TYPE_WCOMBINE	0
+#define MEM_TYPE_NONCACHED	1
+#define MEM_TYPE_NORMAL		2
+
 static void *persistent_ram_vmap(phys_addr_t start, size_t size,
 		unsigned int memtype)
 {
@@ -411,10 +413,20 @@ static void *persistent_ram_vmap(phys_addr_t start, size_t size,
 	page_start = start - offset_in_page(start);
 	page_count = DIV_ROUND_UP(size + offset_in_page(start), PAGE_SIZE);
 
-	if (memtype)
+	switch (memtype) {
+	case MEM_TYPE_NORMAL:
+		prot = PAGE_KERNEL;
+		break;
+	case MEM_TYPE_NONCACHED:
 		prot = pgprot_noncached(PAGE_KERNEL);
-	else
+		break;
+	case MEM_TYPE_WCOMBINE:
 		prot = pgprot_writecombine(PAGE_KERNEL);
+		break;
+	default:
+		pr_err("invalid mem_type=%d\n", memtype);
+		return NULL;
+	}
 
 	pages = kmalloc_array(page_count, sizeof(struct page *), GFP_KERNEL);
 	if (!pages) {