null_blk: fix zoned support for non-rq based operation
authorJens Axboe <axboe@kernel.dk>
Thu, 13 Sep 2018 00:21:11 +0000 (18:21 -0600)
committerJens Axboe <axboe@kernel.dk>
Thu, 13 Sep 2018 00:21:11 +0000 (18:21 -0600)
The supported added for zones in null_blk seem to assume that only rq
based operation is possible. But this depends on the queue_mode setting,
if this is set to 0, then cmd->bio is what we need to be operating on.
Right now any attempt to load null_blk with queue_mode=0 will
insta-crash, since cmd->rq is NULL and null_handle_cmd() assumes it to
always be set.

Make the zoned code deal with bio's instead, or pass in the
appropriate sector/nr_sectors instead.

Fixes: ca4b2a011948 ("null_blk: add zone support")
Tested-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
drivers/block/null_blk.h
drivers/block/null_blk_main.c
drivers/block/null_blk_zoned.c

index d81781f..34e0030 100644 (file)
@@ -87,10 +87,10 @@ struct nullb {
 #ifdef CONFIG_BLK_DEV_ZONED
 int null_zone_init(struct nullb_device *dev);
 void null_zone_exit(struct nullb_device *dev);
-blk_status_t null_zone_report(struct nullb *nullb,
-                                           struct nullb_cmd *cmd);
-void null_zone_write(struct nullb_cmd *cmd);
-void null_zone_reset(struct nullb_cmd *cmd);
+blk_status_t null_zone_report(struct nullb *nullb, struct bio *bio);
+void null_zone_write(struct nullb_cmd *cmd, sector_t sector,
+                       unsigned int nr_sectors);
+void null_zone_reset(struct nullb_cmd *cmd, sector_t sector);
 #else
 static inline int null_zone_init(struct nullb_device *dev)
 {
@@ -98,11 +98,14 @@ static inline int null_zone_init(struct nullb_device *dev)
 }
 static inline void null_zone_exit(struct nullb_device *dev) {}
 static inline blk_status_t null_zone_report(struct nullb *nullb,
-                                           struct nullb_cmd *cmd)
+                                           struct bio *bio)
 {
        return BLK_STS_NOTSUPP;
 }
-static inline void null_zone_write(struct nullb_cmd *cmd) {}
-static inline void null_zone_reset(struct nullb_cmd *cmd) {}
+static inline void null_zone_write(struct nullb_cmd *cmd, sector_t sector,
+                                  unsigned int nr_sectors)
+{
+}
+static inline void null_zone_reset(struct nullb_cmd *cmd, sector_t sector) {}
 #endif /* CONFIG_BLK_DEV_ZONED */
 #endif /* __NULL_BLK_H */
index 6127e3f..093b614 100644 (file)
@@ -1157,16 +1157,33 @@ static void null_restart_queue_async(struct nullb *nullb)
        }
 }
 
+static bool cmd_report_zone(struct nullb *nullb, struct nullb_cmd *cmd)
+{
+       struct nullb_device *dev = cmd->nq->dev;
+
+       if (dev->queue_mode == NULL_Q_BIO) {
+               if (bio_op(cmd->bio) == REQ_OP_ZONE_REPORT) {
+                       cmd->error = null_zone_report(nullb, cmd->bio);
+                       return true;
+               }
+       } else {
+               if (req_op(cmd->rq) == REQ_OP_ZONE_REPORT) {
+                       cmd->error = null_zone_report(nullb, cmd->rq->bio);
+                       return true;
+               }
+       }
+
+       return false;
+}
+
 static blk_status_t null_handle_cmd(struct nullb_cmd *cmd)
 {
        struct nullb_device *dev = cmd->nq->dev;
        struct nullb *nullb = dev->nullb;
        int err = 0;
 
-       if (req_op(cmd->rq) == REQ_OP_ZONE_REPORT) {
-               cmd->error = null_zone_report(nullb, cmd);
+       if (cmd_report_zone(nullb, cmd))
                goto out;
-       }
 
        if (test_bit(NULLB_DEV_FL_THROTTLED, &dev->flags)) {
                struct request *rq = cmd->rq;
@@ -1234,10 +1251,24 @@ static blk_status_t null_handle_cmd(struct nullb_cmd *cmd)
        cmd->error = errno_to_blk_status(err);
 
        if (!cmd->error && dev->zoned) {
-               if (req_op(cmd->rq) == REQ_OP_WRITE)
-                       null_zone_write(cmd);
-               else if (req_op(cmd->rq) == REQ_OP_ZONE_RESET)
-                       null_zone_reset(cmd);
+               sector_t sector;
+               unsigned int nr_sectors;
+               int op;
+
+               if (dev->queue_mode == NULL_Q_BIO) {
+                       op = bio_op(cmd->bio);
+                       sector = cmd->bio->bi_iter.bi_sector;
+                       nr_sectors = cmd->bio->bi_iter.bi_size >> 9;
+               } else {
+                       op = req_op(cmd->rq);
+                       sector = blk_rq_pos(cmd->rq);
+                       nr_sectors = blk_rq_sectors(cmd->rq);
+               }
+
+               if (op == REQ_OP_WRITE)
+                       null_zone_write(cmd, sector, nr_sectors);
+               else if (op == REQ_OP_ZONE_RESET)
+                       null_zone_reset(cmd, sector);
        }
 out:
        /* Complete IO by inline, softirq or timer */
index a979ca0..7c6b86d 100644 (file)
@@ -48,8 +48,8 @@ void null_zone_exit(struct nullb_device *dev)
        kvfree(dev->zones);
 }
 
-static void null_zone_fill_rq(struct nullb_device *dev, struct request *rq,
-                             unsigned int zno, unsigned int nr_zones)
+static void null_zone_fill_bio(struct nullb_device *dev, struct bio *bio,
+                              unsigned int zno, unsigned int nr_zones)
 {
        struct blk_zone_report_hdr *hdr = NULL;
        struct bio_vec bvec;
@@ -57,7 +57,7 @@ static void null_zone_fill_rq(struct nullb_device *dev, struct request *rq,
        void *addr;
        unsigned int zones_to_cpy;
 
-       bio_for_each_segment(bvec, rq->bio, iter) {
+       bio_for_each_segment(bvec, bio, iter) {
                addr = kmap_atomic(bvec.bv_page);
 
                zones_to_cpy = bvec.bv_len / sizeof(struct blk_zone);
@@ -84,29 +84,24 @@ static void null_zone_fill_rq(struct nullb_device *dev, struct request *rq,
        }
 }
 
-blk_status_t null_zone_report(struct nullb *nullb,
-                                    struct nullb_cmd *cmd)
+blk_status_t null_zone_report(struct nullb *nullb, struct bio *bio)
 {
        struct nullb_device *dev = nullb->dev;
-       struct request *rq = cmd->rq;
-       unsigned int zno = null_zone_no(dev, blk_rq_pos(rq));
+       unsigned int zno = null_zone_no(dev, bio->bi_iter.bi_sector);
        unsigned int nr_zones = dev->nr_zones - zno;
-       unsigned int max_zones = (blk_rq_bytes(rq) /
-                                       sizeof(struct blk_zone)) - 1;
+       unsigned int max_zones;
 
+       max_zones = (bio->bi_iter.bi_size / sizeof(struct blk_zone)) - 1;
        nr_zones = min_t(unsigned int, nr_zones, max_zones);
-
-       null_zone_fill_rq(nullb->dev, rq, zno, nr_zones);
+       null_zone_fill_bio(nullb->dev, bio, zno, nr_zones);
 
        return BLK_STS_OK;
 }
 
-void null_zone_write(struct nullb_cmd *cmd)
+void null_zone_write(struct nullb_cmd *cmd, sector_t sector,
+                    unsigned int nr_sectors)
 {
        struct nullb_device *dev = cmd->nq->dev;
-       struct request *rq = cmd->rq;
-       sector_t sector = blk_rq_pos(rq);
-       unsigned int rq_sectors = blk_rq_sectors(rq);
        unsigned int zno = null_zone_no(dev, sector);
        struct blk_zone *zone = &dev->zones[zno];
 
@@ -118,7 +113,7 @@ void null_zone_write(struct nullb_cmd *cmd)
        case BLK_ZONE_COND_EMPTY:
        case BLK_ZONE_COND_IMP_OPEN:
                /* Writes must be at the write pointer position */
-               if (blk_rq_pos(rq) != zone->wp) {
+               if (sector != zone->wp) {
                        cmd->error = BLK_STS_IOERR;
                        break;
                }
@@ -126,7 +121,7 @@ void null_zone_write(struct nullb_cmd *cmd)
                if (zone->cond == BLK_ZONE_COND_EMPTY)
                        zone->cond = BLK_ZONE_COND_IMP_OPEN;
 
-               zone->wp += rq_sectors;
+               zone->wp += nr_sectors;
                if (zone->wp == zone->start + zone->len)
                        zone->cond = BLK_ZONE_COND_FULL;
                break;
@@ -137,11 +132,10 @@ void null_zone_write(struct nullb_cmd *cmd)
        }
 }
 
-void null_zone_reset(struct nullb_cmd *cmd)
+void null_zone_reset(struct nullb_cmd *cmd, sector_t sector)
 {
        struct nullb_device *dev = cmd->nq->dev;
-       struct request *rq = cmd->rq;
-       unsigned int zno = null_zone_no(dev, blk_rq_pos(rq));
+       unsigned int zno = null_zone_no(dev, sector);
        struct blk_zone *zone = &dev->zones[zno];
 
        zone->cond = BLK_ZONE_COND_EMPTY;