Commit ffad0a44 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Theodore Ts'o
Browse files

ext4: ext4_find_next_zero_bit needs an aligned address on some arch 

ext4_find_next_zero_bit and ext4_find_next_bit needs a long aligned
address on x8_64. Add mb_find_next_zero_bit and mb_find_next_bit
and use them in the mballoc.

Fix: https://bugzilla.redhat.com/show_bug.cgi?id=433286



Eric Sandeen debugged the problem and suggested the fix.

Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: default avatarEric Sandeen <sandeen@redhat.com>
Signed-off-by: default avatarMingming Cao <cmm@us.ibm.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent 42bf0383

fs/ext4/mballoc.c

+40 −22
Original line number Diff line number Diff line
@@ -627,21 +627,19 @@ static ext4_fsblk_t ext4_grp_offs_to_block(struct super_block *sb, 
	return block;

}



static inline void *mb_correct_addr_and_bit(int *bit, void *addr)

{

#if BITS_PER_LONG == 64

#define mb_correct_addr_and_bit(bit, addr)		\

{							\

	bit += ((unsigned long) addr & 7UL) << 3;	\

	addr = (void *) ((unsigned long) addr & ~7UL);	\

}

	*bit += ((unsigned long) addr & 7UL) << 3;

	addr = (void *) ((unsigned long) addr & ~7UL);

#elif BITS_PER_LONG == 32

#define mb_correct_addr_and_bit(bit, addr)		\

{							\

	bit += ((unsigned long) addr & 3UL) << 3;	\

	addr = (void *) ((unsigned long) addr & ~3UL);	\

}

	*bit += ((unsigned long) addr & 3UL) << 3;

	addr = (void *) ((unsigned long) addr & ~3UL);

#else

#error "how many bits you are?!"

#endif

	return addr;

}



static inline int mb_test_bit(int bit, void *addr)

{
@@ -649,34 +647,54 @@ static inline int mb_test_bit(int bit, void *addr) 
	 * ext4_test_bit on architecture like powerpc

	 * needs unsigned long aligned address

	 */

	mb_correct_addr_and_bit(bit, addr);

	addr = mb_correct_addr_and_bit(&bit, addr);

	return ext4_test_bit(bit, addr);

}



static inline void mb_set_bit(int bit, void *addr)

{

	mb_correct_addr_and_bit(bit, addr);

	addr = mb_correct_addr_and_bit(&bit, addr);

	ext4_set_bit(bit, addr);

}



static inline void mb_set_bit_atomic(spinlock_t *lock, int bit, void *addr)

{

	mb_correct_addr_and_bit(bit, addr);

	addr = mb_correct_addr_and_bit(&bit, addr);

	ext4_set_bit_atomic(lock, bit, addr);

}



static inline void mb_clear_bit(int bit, void *addr)

{

	mb_correct_addr_and_bit(bit, addr);

	addr = mb_correct_addr_and_bit(&bit, addr);

	ext4_clear_bit(bit, addr);

}



static inline void mb_clear_bit_atomic(spinlock_t *lock, int bit, void *addr)

{

	mb_correct_addr_and_bit(bit, addr);

	addr = mb_correct_addr_and_bit(&bit, addr);

	ext4_clear_bit_atomic(lock, bit, addr);

}



static inline int mb_find_next_zero_bit(void *addr, int max, int start)

{

	int fix = 0;

	addr = mb_correct_addr_and_bit(&fix, addr);

	max += fix;

	start += fix;



	return ext4_find_next_zero_bit(addr, max, start) - fix;

}



static inline int mb_find_next_bit(void *addr, int max, int start)

{

	int fix = 0;

	addr = mb_correct_addr_and_bit(&fix, addr);

	max += fix;

	start += fix;



	return ext4_find_next_bit(addr, max, start) - fix;

}



static void *mb_find_buddy(struct ext4_buddy *e4b, int order, int *max)

{

	char *bb;
@@ -946,12 +964,12 @@ static void ext4_mb_generate_buddy(struct super_block *sb, 


	/* initialize buddy from bitmap which is aggregation

	 * of on-disk bitmap and preallocations */

	i = ext4_find_next_zero_bit(bitmap, max, 0);

	i = mb_find_next_zero_bit(bitmap, max, 0);

	grp->bb_first_free = i;

	while (i < max) {

		fragments++;

		first = i;

		i = ext4_find_next_bit(bitmap, max, i);

		i = mb_find_next_bit(bitmap, max, i);

		len = i - first;

		free += len;

		if (len > 1)
@@ -959,7 +977,7 @@ static void ext4_mb_generate_buddy(struct super_block *sb, 
		else

			grp->bb_counters[0]++;

		if (i < max)

			i = ext4_find_next_zero_bit(bitmap, max, i);

			i = mb_find_next_zero_bit(bitmap, max, i);

	}

	grp->bb_fragments = fragments;
@@ -1782,7 +1800,7 @@ static void ext4_mb_simple_scan_group(struct ext4_allocation_context *ac, 
		buddy = mb_find_buddy(e4b, i, &max);

		BUG_ON(buddy == NULL);



		k = ext4_find_next_zero_bit(buddy, max, 0);

		k = mb_find_next_zero_bit(buddy, max, 0);

		BUG_ON(k >= max);



		ac->ac_found++;
@@ -1822,7 +1840,7 @@ static void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac, 
	i = e4b->bd_info->bb_first_free;



	while (free && ac->ac_status == AC_STATUS_CONTINUE) {

		i = ext4_find_next_zero_bit(bitmap,

		i = mb_find_next_zero_bit(bitmap,

						EXT4_BLOCKS_PER_GROUP(sb), i);

		if (i >= EXT4_BLOCKS_PER_GROUP(sb)) {

			/*
@@ -3750,10 +3768,10 @@ static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b, 
	}



	while (bit < end) {

		bit = ext4_find_next_zero_bit(bitmap_bh->b_data, end, bit);

		bit = mb_find_next_zero_bit(bitmap_bh->b_data, end, bit);

		if (bit >= end)

			break;

		next = ext4_find_next_bit(bitmap_bh->b_data, end, bit);

		next = mb_find_next_bit(bitmap_bh->b_data, end, bit);

		if (next > end)

			next = end;

		start = group * EXT4_BLOCKS_PER_GROUP(sb) + bit +

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