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>
This commit is contained in:
Joe Thornber 2013-03-20 17:21:25 +00:00 committed by Alasdair G Kergon
parent 3b6b7813b1
commit 414dd67d50

View File

@ -158,7 +158,7 @@ struct cache {
/*
* 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 @@ static bool block_size_is_power_of_two(struct cache *cache)
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 @@ static void process_discard_bio(struct cache *cache, struct bio *bio)
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 @@ static int cache_create(struct cache_args *ca, struct cache **result)
/* 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 @@ static int cache_create(struct cache_args *ca, struct cache **result)
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);