powerpc/nvram: Fix endian issue when using the partition length

When reading partitions, the length has to be translated from
big endian to the endian order of the host. Similarly, when writing
partitions, the length needs to be in big endian order.

The userspace tool 'nvram' needs a similar fix as it is reading
and writing partitions through /dev/nram :

    http://sourceforge.net/p/powerpc-utils/mailman/message/31571277/

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 8 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index 8213ee1eb05a..fd82c289ab1c 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -223,9 +223,13 @@ static int __init nvram_write_header(struct nvram_partition * part)
 {
         loff_t tmp_index;
         int rc;
-        
+        struct nvram_header phead;
+
+        memcpy(&phead, &part->header, NVRAM_HEADER_LEN);
+        phead.length = cpu_to_be16(phead.length);
+
         tmp_index = part->index;
-        rc = ppc_md.nvram_write((char *)&part->header, NVRAM_HEADER_LEN, &tmp_index); 
+        rc = ppc_md.nvram_write((char *)&phead, NVRAM_HEADER_LEN, &tmp_index);
 
         return rc;
 }
@@ -505,6 +509,8 @@ int __init nvram_scan_partitions(void)
 
                 memcpy(&phead, header, NVRAM_HEADER_LEN);
 
+                phead.length = be16_to_cpu(phead.length);
+
                 err = 0;
                 c_sum = nvram_checksum(&phead);
                 if (c_sum != phead.checksum) {