Re: [PATCH] block: Fix secure erase

From: Shaun Tancheff
Date: Mon Aug 15 2016 - 12:43:47 EST

On Mon, Aug 15, 2016 at 9:07 AM, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
> Commit 288dab8a35a0 ("block: add a separate operation type for secure
> erase") split REQ_OP_SECURE_ERASE from REQ_OP_DISCARD without considering
> all the places REQ_OP_DISCARD was being used to mean either. Fix those.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Fixes: 288dab8a35a0 ("block: add a separate operation type for secure erase")
> ---
> block/bio.c | 21 +++++++++++----------
> block/blk-merge.c | 33 +++++++++++++++++++--------------
> block/elevator.c | 5 ++++-
> drivers/mmc/card/block.c | 1 +
> drivers/mmc/card/queue.c | 3 ++-
> drivers/mmc/card/queue.h | 4 +++-
> include/linux/bio.h | 10 ++++++++--
> include/linux/blkdev.h | 6 ++++--
> kernel/trace/blktrace.c | 2 +-
> 9 files changed, 53 insertions(+), 32 deletions(-)

Hmm ... Since REQ_SECURE implied REQ_DISCARD doesn't this
mean that we should include REQ_OP_SECURE_ERASE checking
wherever REQ_OP_DISCARD is being checked now in drivers/scsi/sd.c ?

(It's only in 3 spots so it's a quickie patch)

> diff --git a/block/bio.c b/block/bio.c
> index f39477538fef..aa7354088008 100644
> --- a/block/bio.c
> +++ b/block/bio.c
> @@ -667,18 +667,19 @@ struct bio *bio_clone_bioset(struct bio *bio_src, gfp_t gfp_mask,
> bio->bi_iter.bi_sector = bio_src->bi_iter.bi_sector;
> bio->bi_iter.bi_size = bio_src->bi_iter.bi_size;
>
> - if (bio_op(bio) == REQ_OP_DISCARD)
> - goto integrity_clone;
> -
> - if (bio_op(bio) == REQ_OP_WRITE_SAME) {
> + switch (bio_op(bio)) {
> + case REQ_OP_DISCARD:
> + case REQ_OP_SECURE_ERASE:
> + break;
> + case REQ_OP_WRITE_SAME:
> bio->bi_io_vec[bio->bi_vcnt++] = bio_src->bi_io_vec[0];
> - goto integrity_clone;
> + break;
> + default:
> + bio_for_each_segment(bv, bio_src, iter)
> + bio->bi_io_vec[bio->bi_vcnt++] = bv;
> + break;
> }
>
> - bio_for_each_segment(bv, bio_src, iter)
> - bio->bi_io_vec[bio->bi_vcnt++] = bv;
> -
> -integrity_clone:
> if (bio_integrity(bio_src)) {
> int ret;
>
> @@ -1788,7 +1789,7 @@ struct bio *bio_split(struct bio *bio, int sectors,
> * Discards need a mutable bio_vec to accommodate the payload
> * required by the DSM TRIM and UNMAP commands.
> */
> - if (bio_op(bio) == REQ_OP_DISCARD)
> + if (bio_op(bio) == REQ_OP_DISCARD || bio_op(bio) == REQ_OP_SECURE_ERASE)
> split = bio_clone_bioset(bio, gfp, bs);
> else
> split = bio_clone_fast(bio, gfp, bs);
> diff --git a/block/blk-merge.c b/block/blk-merge.c
> index 3eec75a9e91d..72627e3cf91e 100644
> --- a/block/blk-merge.c
> +++ b/block/blk-merge.c
> @@ -172,12 +172,18 @@ void blk_queue_split(struct request_queue *q, struct bio **bio,
> struct bio *split, *res;
> unsigned nsegs;
>
> - if (bio_op(*bio) == REQ_OP_DISCARD)
> + switch (bio_op(*bio)) {
> + case REQ_OP_DISCARD:
> + case REQ_OP_SECURE_ERASE:
> split = blk_bio_discard_split(q, *bio, bs, &nsegs);
> - else if (bio_op(*bio) == REQ_OP_WRITE_SAME)
> + break;
> + case REQ_OP_WRITE_SAME:
> split = blk_bio_write_same_split(q, *bio, bs, &nsegs);
> - else
> + break;
> + default:
> split = blk_bio_segment_split(q, *bio, q->bio_split, &nsegs);
> + break;
> + }
>
> /* physical segments can be figured out during splitting */
> res = split ? split : *bio;
> @@ -213,7 +219,7 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
> * This should probably be returning 0, but blk_add_request_payload()
> * (Christoph!!!!)
> */
> - if (bio_op(bio) == REQ_OP_DISCARD)
> + if (bio_op(bio) == REQ_OP_DISCARD || bio_op(bio) == REQ_OP_SECURE_ERASE)
> return 1;
>
> if (bio_op(bio) == REQ_OP_WRITE_SAME)
> @@ -385,7 +391,9 @@ static int __blk_bios_map_sg(struct request_queue *q, struct bio *bio,
> nsegs = 0;
> cluster = blk_queue_cluster(q);
>
> - if (bio_op(bio) == REQ_OP_DISCARD) {
> + switch (bio_op(bio)) {
> + case REQ_OP_DISCARD:
> + case REQ_OP_SECURE_ERASE:
> /*
> * This is a hack - drivers should be neither modifying the
> * biovec, nor relying on bi_vcnt - but because of
> @@ -393,19 +401,16 @@ static int __blk_bios_map_sg(struct request_queue *q, struct bio *bio,
> * a payload we need to set up here (thank you Christoph) and
> * bi_vcnt is really the only way of telling if we need to.
> */
> -
> - if (bio->bi_vcnt)
> - goto single_segment;
> -
> - return 0;
> - }
> -
> - if (bio_op(bio) == REQ_OP_WRITE_SAME) {
> -single_segment:
> + if (!bio->bi_vcnt)
> + return 0;
> + /* Fall through */
> + case REQ_OP_WRITE_SAME:
> *sg = sglist;
> bvec = bio_iovec(bio);
> sg_set_page(*sg, bvec.bv_page, bvec.bv_len, bvec.bv_offset);
> return 1;
> + default:
> + break;
> }
>
> for_each_bio(bio)
> diff --git a/block/elevator.c b/block/elevator.c
> index 7096c22041e7..e5924504aff6 100644
> --- a/block/elevator.c
> +++ b/block/elevator.c
> @@ -366,7 +366,10 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq)
> list_for_each_prev(entry, &q->queue_head) {
> struct request *pos = list_entry_rq(entry);
>
> - if ((req_op(rq) == REQ_OP_DISCARD) != (req_op(pos) == REQ_OP_DISCARD))
> + if ((req_op(rq) == REQ_OP_DISCARD ||
> + req_op(rq) == REQ_OP_SECURE_ERASE) !=
> + (req_op(pos) == REQ_OP_DISCARD ||
> + req_op(pos) == REQ_OP_SECURE_ERASE))
> break;
> if (rq_data_dir(rq) != rq_data_dir(pos))
> break;
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> index 48a5dd740f3b..82503e6f04b3 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -1726,6 +1726,7 @@ static u8 mmc_blk_prep_packed_list(struct mmc_queue *mq, struct request *req)
> break;
>
> if (req_op(next) == REQ_OP_DISCARD ||
> + req_op(next) == REQ_OP_SECURE_ERASE ||
> req_op(next) == REQ_OP_FLUSH)
> break;
>
> diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
> index bf14642a576a..29578e98603d 100644
> --- a/drivers/mmc/card/queue.c
> +++ b/drivers/mmc/card/queue.c
> @@ -33,7 +33,8 @@ static int mmc_prep_request(struct request_queue *q, struct request *req)
> /*
> * We only like normal block requests and discards.
> */
> - if (req->cmd_type != REQ_TYPE_FS && req_op(req) != REQ_OP_DISCARD) {
> + if (req->cmd_type != REQ_TYPE_FS && req_op(req) != REQ_OP_DISCARD &&
> + req_op(req) != REQ_OP_SECURE_ERASE) {
> blk_dump_rq_flags(req, "MMC bad request");
> return BLKPREP_KILL;
> }
> diff --git a/drivers/mmc/card/queue.h b/drivers/mmc/card/queue.h
> index d62531124d54..fee5e1271465 100644
> --- a/drivers/mmc/card/queue.h
> +++ b/drivers/mmc/card/queue.h
> @@ -4,7 +4,9 @@
> static inline bool mmc_req_is_special(struct request *req)
> {
> return req &&
> - (req_op(req) == REQ_OP_FLUSH || req_op(req) == REQ_OP_DISCARD);
> + (req_op(req) == REQ_OP_FLUSH ||
> + req_op(req) == REQ_OP_DISCARD ||
> + req_op(req) == REQ_OP_SECURE_ERASE);
> }
>
> struct request;
> diff --git a/include/linux/bio.h b/include/linux/bio.h
> index 59ffaa68b11b..23ddf4b46a9b 100644
> --- a/include/linux/bio.h
> +++ b/include/linux/bio.h
> @@ -71,7 +71,8 @@ static inline bool bio_has_data(struct bio *bio)
> {
> if (bio &&
> bio->bi_iter.bi_size &&
> - bio_op(bio) != REQ_OP_DISCARD)
> + bio_op(bio) != REQ_OP_DISCARD &&
> + bio_op(bio) != REQ_OP_SECURE_ERASE)
> return true;
>
> return false;
> @@ -79,7 +80,9 @@ static inline bool bio_has_data(struct bio *bio)
>
> static inline bool bio_no_advance_iter(struct bio *bio)
> {
> - return bio_op(bio) == REQ_OP_DISCARD || bio_op(bio) == REQ_OP_WRITE_SAME;
> + return bio_op(bio) == REQ_OP_DISCARD ||
> + bio_op(bio) == REQ_OP_SECURE_ERASE ||
> + bio_op(bio) == REQ_OP_WRITE_SAME;
> }
>
> static inline bool bio_is_rw(struct bio *bio)
> @@ -199,6 +202,9 @@ static inline unsigned bio_segments(struct bio *bio)
> if (bio_op(bio) == REQ_OP_DISCARD)
> return 1;
>
> + if (bio_op(bio) == REQ_OP_SECURE_ERASE)
> + return 1;
> +
> if (bio_op(bio) == REQ_OP_WRITE_SAME)
> return 1;
>
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index 2c210b6a7bcf..e79055c8b577 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -882,7 +882,7 @@ static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
> static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
> int op)
> {
> - if (unlikely(op == REQ_OP_DISCARD))
> + if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
> return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
>
> if (unlikely(op == REQ_OP_WRITE_SAME))
> @@ -913,7 +913,9 @@ static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
> if (unlikely(rq->cmd_type != REQ_TYPE_FS))
> return q->limits.max_hw_sectors;
>
> - if (!q->limits.chunk_sectors || (req_op(rq) == REQ_OP_DISCARD))
> + if (!q->limits.chunk_sectors ||
> + req_op(rq) == REQ_OP_DISCARD ||
> + req_op(rq) == REQ_OP_SECURE_ERASE)
> return blk_queue_get_max_sectors(q, req_op(rq));
>
> return min(blk_max_size_offset(q, offset),
> diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
> index 7598e6ca817a..dbafc5df03f3 100644
> --- a/kernel/trace/blktrace.c
> +++ b/kernel/trace/blktrace.c
> @@ -223,7 +223,7 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
> what |= MASK_TC_BIT(op_flags, META);
> what |= MASK_TC_BIT(op_flags, PREFLUSH);
> what |= MASK_TC_BIT(op_flags, FUA);
> - if (op == REQ_OP_DISCARD)
> + if (op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE)
> what |= BLK_TC_ACT(BLK_TC_DISCARD);
> if (op == REQ_OP_FLUSH)
> what |= BLK_TC_ACT(BLK_TC_FLUSH);
> --
> 1.9.1
>
> --
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--
Shaun Tancheff