microblaze: Fix bug with mmap2 syscall MB implementation

Fix mmap2 behaviour which incorrectly works with pgoff
not in 4k units.

Reported-by: Rich Felker <dalias@aerifal.cx>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

2 files changed, 12 insertions, 1 deletions

diff --git a/arch/microblaze/kernel/sys_microblaze.c b/arch/microblaze/kernel/sys_microblaze.c
index e80a6c02ac31..f1e1f666ddde 100644
--- a/arch/microblaze/kernel/sys_microblaze.c
+++ b/arch/microblaze/kernel/sys_microblaze.c
@@ -42,3 +42,14 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
 
         return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> PAGE_SHIFT);
 }
+
+SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
+                unsigned long, prot, unsigned long, flags, unsigned long, fd,
+                unsigned long, pgoff)
+{
+        if (pgoff & (~PAGE_MASK >> 12))
+                return -EINVAL;
+
+        return sys_mmap_pgoff(addr, len, prot, flags, fd,
+                              pgoff >> (PAGE_SHIFT - 12));
+}
diff --git a/arch/microblaze/kernel/syscall_table.S b/arch/microblaze/kernel/syscall_table.S
index 4fca56cf02f6..b882ad50535b 100644
--- a/arch/microblaze/kernel/syscall_table.S
+++ b/arch/microblaze/kernel/syscall_table.S
@@ -192,7 +192,7 @@ ENTRY(sys_call_table)
         .long sys_ni_syscall            /* reserved for streams2 */
         .long sys_vfork         /* 190 */
         .long sys_getrlimit
-        .long sys_mmap_pgoff            /* mmap2 */
+        .long sys_mmap2
         .long sys_truncate64
         .long sys_ftruncate64
         .long sys_stat64                /* 195 */