From 54df2db36c93bbb8c757f172d97c577040de6abb Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Fri, 29 Mar 2013 03:44:43 +0000 Subject: sparc/srmmu: clear trailing edge of bitmap properly srmmu_nocache_bitmap is cleared by bit_map_init(). But bit_map_init() attempts to clear by memset(), so it can't clear the trailing edge of bitmap properly on big-endian architecture if the number of bits is not a multiple of BITS_PER_LONG. Actually, the number of bits in srmmu_nocache_bitmap is not always a multiple of BITS_PER_LONG. It is calculated as below: bitmap_bits = srmmu_nocache_size >> SRMMU_NOCACHE_BITMAP_SHIFT; srmmu_nocache_size is decided proportionally by the amount of system RAM and it is rounded to a multiple of PAGE_SIZE. SRMMU_NOCACHE_BITMAP_SHIFT is defined as (PAGE_SHIFT - 4). So it can only be said that bitmap_bits is a multiple of 16. This fixes the problem by using bitmap_clear() instead of memset() in bit_map_init() and this also uses BITS_TO_LONGS() to calculate correct size at bitmap allocation time. Signed-off-by: Akinobu Mita Cc: "David S. Miller" Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller --- arch/sparc/lib/bitext.c | 6 +----- arch/sparc/mm/srmmu.c | 4 +++- 2 files changed, 4 insertions(+), 6 deletions(-) (limited to 'arch') diff --git a/arch/sparc/lib/bitext.c b/arch/sparc/lib/bitext.c index 48d00e72ce15..8ec4e9c0251a 100644 --- a/arch/sparc/lib/bitext.c +++ b/arch/sparc/lib/bitext.c @@ -119,11 +119,7 @@ void bit_map_clear(struct bit_map *t, int offset, int len) void bit_map_init(struct bit_map *t, unsigned long *map, int size) { - - if ((size & 07) != 0) - BUG(); - memset(map, 0, size>>3); - + bitmap_zero(map, size); memset(t, 0, sizeof *t); spin_lock_init(&t->lock); t->map = map; diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c index c38bb72e3e80..036c2797dece 100644 --- a/arch/sparc/mm/srmmu.c +++ b/arch/sparc/mm/srmmu.c @@ -280,7 +280,9 @@ static void __init srmmu_nocache_init(void) SRMMU_NOCACHE_ALIGN_MAX, 0UL); memset(srmmu_nocache_pool, 0, srmmu_nocache_size); - srmmu_nocache_bitmap = __alloc_bootmem(bitmap_bits >> 3, SMP_CACHE_BYTES, 0UL); + srmmu_nocache_bitmap = + __alloc_bootmem(BITS_TO_LONGS(bitmap_bits) * sizeof(long), + SMP_CACHE_BYTES, 0UL); bit_map_init(&srmmu_nocache_map, srmmu_nocache_bitmap, bitmap_bits); srmmu_swapper_pg_dir = __srmmu_get_nocache(SRMMU_PGD_TABLE_SIZE, SRMMU_PGD_TABLE_SIZE); -- cgit v1.2.3