Commit b6b4aafc authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'block-5.5-20200103' of git://git.kernel.dk/linux-block 

Pull block fixes from Jens Axboe:
 "Three fixes in here:

   - Fix for a missing split on default memory boundary mask (4G) (Ming)

   - Fix for multi-page read bio truncate (Ming)

   - Fix for null_blk zone close request handling (Damien)"

* tag 'block-5.5-20200103' of git://git.kernel.dk/linux-block:
  null_blk: Fix REQ_OP_ZONE_CLOSE handling
  block: fix splitting segments on boundary masks
  block: add bio_truncate to fix guard_bio_eod
parents bed72351 c7d776f8

block/bio.c

+39 −0
Original line number Diff line number Diff line
@@ -538,6 +538,45 @@ void zero_fill_bio_iter(struct bio *bio, struct bvec_iter start) 
}

EXPORT_SYMBOL(zero_fill_bio_iter);



void bio_truncate(struct bio *bio, unsigned new_size)

{

	struct bio_vec bv;

	struct bvec_iter iter;

	unsigned int done = 0;

	bool truncated = false;



	if (new_size >= bio->bi_iter.bi_size)

		return;



	if (bio_data_dir(bio) != READ)

		goto exit;



	bio_for_each_segment(bv, bio, iter) {

		if (done + bv.bv_len > new_size) {

			unsigned offset;



			if (!truncated)

				offset = new_size - done;

			else

				offset = 0;

			zero_user(bv.bv_page, offset, bv.bv_len - offset);

			truncated = true;

		}

		done += bv.bv_len;

	}



 exit:

	/*

	 * Don't touch bvec table here and make it really immutable, since

	 * fs bio user has to retrieve all pages via bio_for_each_segment_all

	 * in its .end_bio() callback.

	 *

	 * It is enough to truncate bio by updating .bi_size since we can make

	 * correct bvec with the updated .bi_size for drivers.

	 */

	bio->bi_iter.bi_size = new_size;

}



/**

 * bio_put - release a reference to a bio

 * @bio:   bio to release reference to

block/blk-merge.c

+9 −9
Original line number Diff line number Diff line
@@ -157,16 +157,14 @@ 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);



	return min_t(unsigned long, mask - (mask & offset) + 1,

	offset = mask & (page_to_phys(start_page) + offset);

	return min_t(unsigned long, mask - offset + 1,

		     queue_max_segment_size(q));

}
@@ -201,7 +199,8 @@ 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 +418,8 @@ 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;



		/*

drivers/block/null_blk_zoned.c

+4 −1
Original line number Diff line number Diff line
@@ -186,6 +186,9 @@ static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_opf op, 
		if (zone->cond == BLK_ZONE_COND_FULL)

			return BLK_STS_IOERR;



		if (zone->wp == zone->start)

			zone->cond = BLK_ZONE_COND_EMPTY;

		else

			zone->cond = BLK_ZONE_COND_CLOSED;

		break;

	case REQ_OP_ZONE_FINISH:

fs/buffer.c

+1 −24
Original line number Diff line number Diff line
@@ -3034,8 +3034,6 @@ static void end_bio_bh_io_sync(struct bio *bio) 
void guard_bio_eod(int op, struct bio *bio)

{

	sector_t maxsector;

	struct bio_vec *bvec = bio_last_bvec_all(bio);

	unsigned truncated_bytes;

	struct hd_struct *part;



	rcu_read_lock();
@@ -3061,28 +3059,7 @@ void guard_bio_eod(int op, struct bio *bio) 
	if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))

		return;



	/* Uhhuh. We've got a bio that straddles the device size! */

	truncated_bytes = bio->bi_iter.bi_size - (maxsector << 9);



	/*

	 * The bio contains more than one segment which spans EOD, just return

	 * and let IO layer turn it into an EIO

	 */

	if (truncated_bytes > bvec->bv_len)

		return;



	/* Truncate the bio.. */

	bio->bi_iter.bi_size -= truncated_bytes;

	bvec->bv_len -= truncated_bytes;



	/* ..and clear the end of the buffer for reads */

	if (op == REQ_OP_READ) {

		struct bio_vec bv;



		mp_bvec_last_segment(bvec, &bv);

		zero_user(bv.bv_page, bv.bv_offset + bv.bv_len,

				truncated_bytes);

	}

	bio_truncate(bio, maxsector << 9);

}



static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,

include/linux/bio.h

+1 −0
Original line number Diff line number Diff line
@@ -470,6 +470,7 @@ extern struct bio *bio_copy_user_iov(struct request_queue *, 
				     gfp_t);

extern int bio_uncopy_user(struct bio *);

void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);

void bio_truncate(struct bio *bio, unsigned new_size);



static inline void zero_fill_bio(struct bio *bio)

{

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