diff options
Diffstat (limited to 'block/blk-merge.c')
| -rw-r--r-- | block/blk-merge.c | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c index d783bdc4559b..1534ed736363 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -157,17 +157,20 @@ static inline unsigned get_max_io_size(struct request_queue *q, return sectors & (lbs - 1); } -static unsigned get_max_segment_size(const struct request_queue *q, - unsigned offset) +static inline unsigned get_max_segment_size(const struct request_queue *q, + struct page *start_page, + unsigned long offset) { unsigned long mask = queue_segment_boundary(q); - /* default segment boundary mask means no boundary limit */ - if (mask == BLK_SEG_BOUNDARY_MASK) - return queue_max_segment_size(q); + offset = mask & (page_to_phys(start_page) + offset); - return min_t(unsigned long, mask - (mask & offset) + 1, - queue_max_segment_size(q)); + /* + * overflow may be triggered in case of zero page physical address + * on 32bit arch, use queue's max segment size when that happens. + */ + return min_not_zero(mask - offset + 1, + (unsigned long)queue_max_segment_size(q)); } /** @@ -201,7 +204,8 @@ static bool bvec_split_segs(const struct request_queue *q, unsigned seg_size = 0; while (len && *nsegs < max_segs) { - seg_size = get_max_segment_size(q, bv->bv_offset + total_len); + seg_size = get_max_segment_size(q, bv->bv_page, + bv->bv_offset + total_len); seg_size = min(seg_size, len); (*nsegs)++; @@ -419,7 +423,8 @@ static unsigned blk_bvec_map_sg(struct request_queue *q, while (nbytes > 0) { unsigned offset = bvec->bv_offset + total; - unsigned len = min(get_max_segment_size(q, offset), nbytes); + unsigned len = min(get_max_segment_size(q, bvec->bv_page, + offset), nbytes); struct page *page = bvec->bv_page; /* |