[PATCH] Fix raid0's attempt to divide by 64bit numbers

Apparently sector_div is only guaranteed to work with a 32bit divisor, even
on 64bit architectures.  So allow for this in raid0.

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index e11dd14..2120710 100644 (file)
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -314,16 +314,16 @@ static int raid0_run (mddev_t *mddev)
                sector_t space = conf->hash_spacing;
                int round;
                conf->preshift = 0;
-               if (sizeof(sector_t) > sizeof(unsigned long)) {
+               if (sizeof(sector_t) > sizeof(u32)) {
                        /*shift down space and s so that sector_div will work */
-                       while (space > (sector_t) (~(unsigned long)0)) {
+                       while (space > (sector_t) (~(u32)0)) {
                                s >>= 1;
                                space >>= 1;
                                s += 1; /* force round-up */
                                conf->preshift++;
                        }
                }
-               round = sector_div(s, (unsigned long)space) ? 1 : 0;
+               round = sector_div(s, (u32)space) ? 1 : 0;
                nb_zone = s + round;
        }
        printk("raid0 : nb_zone is %d.\n", nb_zone);
@@ -443,7 +443,7 @@ static int raid0_make_request (request_queue_t *q, struct bio *bio)
                volatile
 #endif
                sector_t x = block >> conf->preshift;
-               sector_div(x, (unsigned long)conf->hash_spacing);
+               sector_div(x, (u32)conf->hash_spacing);
                zone = conf->hash_table[x];
        }