sd/skd: stuff discard page in request->completion_data

Store the pointer to the page there, so we can always safely
reference it from end_io context where ->bio may have been
cleared.

Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/block/skd_main.c b/drivers/block/skd_main.c
index 36bcedf..c48d908 100644 (file)
--- a/drivers/block/skd_main.c
+++ b/drivers/block/skd_main.c
@@ -743,6 +743,7 @@ static void skd_request_fn(struct request_queue *q)
                                break;
                        }
                        skreq->discard_page = 1;
+                       req->completion_data = page;
                        skd_prep_discard_cdb(scsi_req, skreq, page, lba, count);
 
                } else if (flush == SKD_FLUSH_ZERO_SIZE_FIRST) {
@@ -855,10 +856,9 @@ static void skd_end_request(struct skd_device *skdev,
 
        if ((io_flags & REQ_DISCARD) &&
                (skreq->discard_page == 1)) {
-               struct bio *bio = req->bio;
                pr_debug("%s:%s:%d, free the page!",
                         skdev->name, __func__, __LINE__);
-               __free_page(bio->bi_io_vec->bv_page);
+               __free_page(req->completion_data);
        }
 
        if (unlikely(error)) {

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 06d154d..96af195 100644 (file)
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -737,6 +737,7 @@ static int sd_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
                goto out;
        }
 
+       rq->completion_data = page;
        blk_add_request_payload(rq, page, len);
        ret = scsi_setup_blk_pc_cmnd(sdp, rq);
        rq->__data_len = nr_bytes;
@@ -839,11 +840,9 @@ static void sd_unprep_fn(struct request_queue *q, struct request *rq)
 {
        struct scsi_cmnd *SCpnt = rq->special;
 
-       if (rq->cmd_flags & REQ_DISCARD) {
-               struct bio *bio = rq->bio;
+       if (rq->cmd_flags & REQ_DISCARD)
+               __free_page(rq->completion_data);
 
-               __free_page(bio->bi_io_vec->bv_page);
-       }
        if (SCpnt->cmnd != rq->cmd) {
                mempool_free(SCpnt->cmnd, sd_cdb_pool);
                SCpnt->cmnd = NULL;