mm: try both endianess when checking for endianess

When checking for the swap header try byteswapping the endianess dependent
fields to allow the swap partition to be shared between big & little endian
systems.

Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 2da149cfc9ac..67051be7083a 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1582,6 +1582,14 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
                 error = -EINVAL;
                 goto bad_swap;
         case 2:
+                /* swap partition endianess hack... */
+                if (swab32(swap_header->info.version) == 1) {
+                        swab32s(&swap_header->info.version);
+                        swab32s(&swap_header->info.last_page);
+                        swab32s(&swap_header->info.nr_badpages);
+                        for (i = 0; i < swap_header->info.nr_badpages; i++)
+                                swab32s(&swap_header->info.badpages[i]);
+                }
                 /* Check the swap header's sub-version and the size of
                    the swap file and bad block lists */
                 if (swap_header->info.version != 1) {