+long compat_get_bitmap(unsigned long *mask, compat_ulong_t __user *umask,
+ unsigned long bitmap_size)
+{
+ int i, j;
+ unsigned long m;
+ compat_ulong_t um;
+ unsigned long nr_compat_longs;
+
+ /* align bitmap up to nearest compat_long_t boundary */
+ bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
+
+ if (verify_area(VERIFY_READ, umask, bitmap_size / 8))
+ return -EFAULT;
+
+ nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
+
+ for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
+ m = 0;
+
+ for (j = 0; j < sizeof(m)/sizeof(um); j++) {
+ /*
+ * We dont want to read past the end of the userspace
+ * bitmap. We must however ensure the end of the
+ * kernel bitmap is zeroed.
+ */
+ if (nr_compat_longs-- > 0) {
+ if (__get_user(um, umask))
+ return -EFAULT;
+ } else {
+ um = 0;
+ }
+
+ umask++;
+ m |= (long)um << (j * BITS_PER_COMPAT_LONG);
+ }
+ *mask++ = m;
+ }
+
+ return 0;
+}
+
+long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
+ unsigned long bitmap_size)
+{
+ int i, j;
+ unsigned long m;
+ compat_ulong_t um;
+ unsigned long nr_compat_longs;
+
+ /* align bitmap up to nearest compat_long_t boundary */
+ bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
+
+ if (verify_area(VERIFY_WRITE, umask, bitmap_size / 8))
+ return -EFAULT;
+
+ nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
+
+ for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
+ m = *mask++;
+
+ for (j = 0; j < sizeof(m)/sizeof(um); j++) {
+ um = m;
+
+ /*
+ * We dont want to write past the end of the userspace
+ * bitmap.
+ */
+ if (nr_compat_longs-- > 0) {
+ if (__put_user(um, umask))
+ return -EFAULT;
+ }
+
+ umask++;
+ m >>= 4*sizeof(um);
+ m >>= 4*sizeof(um);
+ }
+ }
+
+ return 0;
+}