The patch titled ocfs2: avoid unaligned access to dqc_bitmap has been added to the -mm tree. Its filename is ocfs2-avoid-unaligned-access-to-dqc_bitmap.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: ocfs2: avoid unaligned access to dqc_bitmap From: Akinobu Mita <akinobu.mita@xxxxxxxxx> The dqc_bitmap field of struct ocfs2_local_disk_chunk is 32-bit aligned, but not 64-bit aligned. The dqc_bitmap is accessed by ocfs2_set_bit(), ocfs2_clear_bit(), ocfs2_test_bit(), or ocfs2_find_next_zero_bit(). These are wrapper macros for ext2_*_bit() which need to take an unsigned long aligned address (though some architectures are able to handle unaligned address correctly) So some 64bit architectures may not be able to access the dqc_bitmap correctly. This avoids such unaligned access by using another wrapper functions for ext2_*_bit(). The code is taken from fs/ext4/mballoc.c which also need to handle unaligned bitmap access. Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> Acked-by: Joel Becker <jlbec@xxxxxxxxxxxx> Cc: Mark Fasheh <mfasheh@xxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/ocfs2/ocfs2.h | 47 +++++++++++++++++++++++++++++++++++++++ fs/ocfs2/quota_local.c | 10 ++++---- 2 files changed, 52 insertions(+), 5 deletions(-) diff -puN fs/ocfs2/ocfs2.h~ocfs2-avoid-unaligned-access-to-dqc_bitmap fs/ocfs2/ocfs2.h --- a/fs/ocfs2/ocfs2.h~ocfs2-avoid-unaligned-access-to-dqc_bitmap +++ a/fs/ocfs2/ocfs2.h @@ -849,5 +849,52 @@ static inline void _ocfs2_clear_bit(unsi #define ocfs2_test_bit test_bit_le #define ocfs2_find_next_zero_bit find_next_zero_bit_le #define ocfs2_find_next_bit find_next_bit_le + +static inline void *correct_addr_and_bit_unaligned(int *bit, void *addr) +{ +#if BITS_PER_LONG == 64 + *bit += ((unsigned long) addr & 7UL) << 3; + addr = (void *) ((unsigned long) addr & ~7UL); +#elif BITS_PER_LONG == 32 + *bit += ((unsigned long) addr & 3UL) << 3; + addr = (void *) ((unsigned long) addr & ~3UL); +#else +#error "how many bits you are?!" +#endif + return addr; +} + +static inline void ocfs2_set_bit_unaligned(int bit, void *bitmap) +{ + bitmap = correct_addr_and_bit_unaligned(&bit, bitmap); + ocfs2_set_bit(bit, bitmap); +} + +static inline void ocfs2_clear_bit_unaligned(int bit, void *bitmap) +{ + bitmap = correct_addr_and_bit_unaligned(&bit, bitmap); + ocfs2_clear_bit(bit, bitmap); +} + +static inline int ocfs2_test_bit_unaligned(int bit, void *bitmap) +{ + bitmap = correct_addr_and_bit_unaligned(&bit, bitmap); + return ocfs2_test_bit(bit, bitmap); +} + +static inline int ocfs2_find_next_zero_bit_unaligned(void *bitmap, int max, + int start) +{ + int fix = 0, ret, tmpmax; + bitmap = correct_addr_and_bit_unaligned(&fix, bitmap); + tmpmax = max + fix; + start += fix; + + ret = ocfs2_find_next_zero_bit(bitmap, tmpmax, start) - fix; + if (ret > max) + return max; + return ret; +} + #endif /* OCFS2_H */ diff -puN fs/ocfs2/quota_local.c~ocfs2-avoid-unaligned-access-to-dqc_bitmap fs/ocfs2/quota_local.c --- a/fs/ocfs2/quota_local.c~ocfs2-avoid-unaligned-access-to-dqc_bitmap +++ a/fs/ocfs2/quota_local.c @@ -549,8 +549,8 @@ static int ocfs2_recover_local_quota_fil goto out_commit; } lock_buffer(qbh); - WARN_ON(!ocfs2_test_bit(bit, dchunk->dqc_bitmap)); - ocfs2_clear_bit(bit, dchunk->dqc_bitmap); + WARN_ON(!ocfs2_test_bit_unaligned(bit, dchunk->dqc_bitmap)); + ocfs2_clear_bit_unaligned(bit, dchunk->dqc_bitmap); le32_add_cpu(&dchunk->dqc_free, 1); unlock_buffer(qbh); ocfs2_journal_dirty(handle, qbh); @@ -944,7 +944,7 @@ static struct ocfs2_quota_chunk *ocfs2_f * ol_quota_entries_per_block(sb); } - found = ocfs2_find_next_zero_bit(dchunk->dqc_bitmap, len, 0); + found = ocfs2_find_next_zero_bit_unaligned(dchunk->dqc_bitmap, len, 0); /* We failed? */ if (found == len) { mlog(ML_ERROR, "Did not find empty entry in chunk %d with %u" @@ -1208,7 +1208,7 @@ static void olq_alloc_dquot(struct buffe struct ocfs2_local_disk_chunk *dchunk; dchunk = (struct ocfs2_local_disk_chunk *)bh->b_data; - ocfs2_set_bit(*offset, dchunk->dqc_bitmap); + ocfs2_set_bit_unaligned(*offset, dchunk->dqc_bitmap); le32_add_cpu(&dchunk->dqc_free, -1); } @@ -1289,7 +1289,7 @@ int ocfs2_local_release_dquot(handle_t * (od->dq_chunk->qc_headerbh->b_data); /* Mark structure as freed */ lock_buffer(od->dq_chunk->qc_headerbh); - ocfs2_clear_bit(offset, dchunk->dqc_bitmap); + ocfs2_clear_bit_unaligned(offset, dchunk->dqc_bitmap); le32_add_cpu(&dchunk->dqc_free, 1); unlock_buffer(od->dq_chunk->qc_headerbh); ocfs2_journal_dirty(handle, od->dq_chunk->qc_headerbh); _ Patches currently in -mm which might be from akinobu.mita@xxxxxxxxx are linux-next.patch dm-use-use-proper-little-endian-bitops.patch ext4-use-proper-little-endian-bitops.patch ocfs2-avoid-unaligned-access-to-dqc_bitmap.patch md-use-proper-little-endian-bitops.patch reiserfs-use-proper-little-endian-bitops.patch reiserfs-use-hweight_long.patch asm-generic-add-another-generic-ext2-atomic-bitops.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html