dm cache: avoid 64 bit division on 32 bit
Squash various 32bit link errors.
>> on i386:
>> drivers/built-in.o: In function `is_discarded_oblock':
>> dm-cache-target.c:(.text+0x1ea28e): undefined reference to `__udivdi3'
...
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 0f4e84b..5ad227f 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -158,7 +158,7 @@
/*
* origin_blocks entries, discarded if set.
*/
- sector_t discard_block_size; /* a power of 2 times sectors per block */
+ uint32_t discard_block_size; /* a power of 2 times sectors per block */
dm_dblock_t discard_nr_blocks;
unsigned long *discard_bitset;
@@ -412,17 +412,24 @@
return cache->sectors_per_block_shift >= 0;
}
+static dm_block_t block_div(dm_block_t b, uint32_t n)
+{
+ do_div(b, n);
+
+ return b;
+}
+
static dm_dblock_t oblock_to_dblock(struct cache *cache, dm_oblock_t oblock)
{
- sector_t discard_blocks = cache->discard_block_size;
+ uint32_t discard_blocks = cache->discard_block_size;
dm_block_t b = from_oblock(oblock);
if (!block_size_is_power_of_two(cache))
- (void) sector_div(discard_blocks, cache->sectors_per_block);
+ discard_blocks = discard_blocks / cache->sectors_per_block;
else
discard_blocks >>= cache->sectors_per_block_shift;
- (void) sector_div(b, discard_blocks);
+ b = block_div(b, discard_blocks);
return to_dblock(b);
}
@@ -1002,7 +1009,7 @@
dm_block_t end_block = bio->bi_sector + bio_sectors(bio);
dm_block_t b;
- (void) sector_div(end_block, cache->discard_block_size);
+ end_block = block_div(end_block, cache->discard_block_size);
for (b = start_block; b < end_block; b++)
set_discard(cache, to_dblock(b));
@@ -1835,7 +1842,7 @@
/* FIXME: factor out this whole section */
origin_blocks = cache->origin_sectors = ca->origin_sectors;
- (void) sector_div(origin_blocks, ca->block_size);
+ origin_blocks = block_div(origin_blocks, ca->block_size);
cache->origin_blocks = to_oblock(origin_blocks);
cache->sectors_per_block = ca->block_size;
@@ -1848,7 +1855,7 @@
dm_block_t cache_size = ca->cache_sectors;
cache->sectors_per_block_shift = -1;
- (void) sector_div(cache_size, ca->block_size);
+ cache_size = block_div(cache_size, ca->block_size);
cache->cache_size = to_cblock(cache_size);
} else {
cache->sectors_per_block_shift = __ffs(ca->block_size);