From b73fce69ecb091a178ef9286027c370a63eb25aa Mon Sep 17 00:00:00 2001 From: Valerie Clement Date: Fri, 15 Feb 2008 13:48:51 -0500 Subject: ext4: Fix kernel BUG at fs/ext4/mballoc.c:910! With the flex_bg feature enabled, a large file creation oopses the kernel. The BUG_ON is: BUG_ON(len >= EXT4_BLOCKS_PER_GROUP(sb)); As the allocation of the bitmaps and the inode table can be done outside the block group with flex_bg, this allows to allocate up to EXT4_BLOCKS_PER_GROUP blocks in a group. This patch fixes the oops. Signed-off-by: Valerie Clement Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ext4/mballoc.c') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index dd0fcfcb35ce..2121184a3fa5 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -906,7 +906,7 @@ static void ext4_mb_mark_free_simple(struct super_block *sb, unsigned short chunk; unsigned short border; - BUG_ON(len >= EXT4_BLOCKS_PER_GROUP(sb)); + BUG_ON(len > EXT4_BLOCKS_PER_GROUP(sb)); border = 2 << sb->s_blocksize_bits; -- cgit v1.2.2 From e56eb6590693a5a340e8f596db2768a6e1b9e236 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Fri, 15 Feb 2008 13:48:21 -0500 Subject: ext4: Don't claim block from group which has corrupt bitmap In ext4_mb_complex_scan_group, if the extent length of the newly found extentet is greater than than the total free blocks counted in group info, break without claiming the block. Document different ext4_error usage, explaining the state with which we continue if we mount with errors=continue Signed-off-by: Aneesh Kumar K.V Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) (limited to 'fs/ext4/mballoc.c') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 2121184a3fa5..6968c53e62ad 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -967,6 +967,10 @@ static void ext4_mb_generate_buddy(struct super_block *sb, ext4_error(sb, __FUNCTION__, "EXT4-fs: group %lu: %u blocks in bitmap, %u in gd\n", group, free, grp->bb_free); + /* + * If we intent to continue, we consider group descritor + * corrupt and update bb_free using bitmap value + */ grp->bb_free = free; } @@ -1822,7 +1826,7 @@ static void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac, EXT4_BLOCKS_PER_GROUP(sb), i); if (i >= EXT4_BLOCKS_PER_GROUP(sb)) { /* - * IF we corrupt the bitmap we won't find any + * IF we have corrupt bitmap, we won't find any * free blocks even though group info says we * we have free blocks */ @@ -1838,6 +1842,12 @@ static void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac, ext4_error(sb, __FUNCTION__, "%d free blocks as per " "group info. But got %d blocks\n", free, ex.fe_len); + /* + * The number of free blocks differs. This mostly + * indicate that the bitmap is corrupt. So exit + * without claiming the space. + */ + break; } ext4_mb_measure_extent(ac, &ex, e4b); @@ -3771,6 +3781,10 @@ static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b, (unsigned long) pa->pa_len); ext4_error(sb, __FUNCTION__, "free %u, pa_free %u\n", free, pa->pa_free); + /* + * pa is already deleted so we use the value obtained + * from the bitmap and continue. + */ } atomic_add(free, &sbi->s_mb_discarded); if (ac) -- cgit v1.2.2 From ffad0a44b7216d0f079dcf95a351082099d1e5fb Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Sat, 23 Feb 2008 01:38:34 -0500 Subject: 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: Aneesh Kumar K.V Acked-by: Eric Sandeen Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 62 +++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 40 insertions(+), 22 deletions(-) (limited to 'fs/ext4/mballoc.c') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 6968c53e62ad..ef97f19c2f9d 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -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 + -- cgit v1.2.2