Ming Lei <ming.lei@xxxxxxxxxx> writes: > On Tue, Jul 11, 2023 at 09:23:53AM +0200, Andreas Hindborg wrote: >> From: Andreas Hindborg <a.hindborg@xxxxxxxxxxx> >> >> Add zoned storage support to ublk: report_zones and operations: >> - REQ_OP_ZONE_OPEN >> - REQ_OP_ZONE_CLOSE >> - REQ_OP_ZONE_FINISH >> - REQ_OP_ZONE_RESET >> - REQ_OP_ZONE_APPEND >> >> The zone append feature uses the `addr` field of `struct ublksrv_io_cmd` to >> communicate ALBA back to the kernel. Therefore ublk must be used with the >> user copy feature (UBLK_F_USER_COPY) for zoned storage support to be >> available. Without this feature, ublk will not allow zoned storage support. > > Without one userspace implementation, it is hard to verify the kernel > change, so I write one zoned target example based on libublk-rs by > taking one day. > > https://github.com/ming1/libublk-rs.git [1] > > It is one zoned-ramdisk example, and should be easy to > add persistence zoned. All zoned commands are covered, except for > REQ_OP_ZONE_RESET_ALL. > > How to create ublk-zoned: > > cargo run --example zoned -- add -1 1024 #1024MB > > So far it passes all blktests/zbd tests for external zoned device. > > 'mkfs.btrfs -O zoned' & mount & git clone linux_kernel in this btrfs > works. > > So this patchset gets verified now, so far so good. Thanks, that is really awesome! I have been testing with a patched version of ubdsrv. It's nice to get some more test coverage options. > > [1] not publish to crates.io yet, still need some cleanup > >> >> Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxxx> >> --- >> drivers/block/ublk_drv.c | 314 ++++++++++++++++++++++++++++++++-- >> include/uapi/linux/ublk_cmd.h | 36 +++- >> 2 files changed, 331 insertions(+), 19 deletions(-) >> >> diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c >> index 8d271901efac..a57be961b708 100644 >> --- a/drivers/block/ublk_drv.c >> +++ b/drivers/block/ublk_drv.c >> @@ -56,16 +56,21 @@ >> | UBLK_F_USER_RECOVERY_REISSUE \ >> | UBLK_F_UNPRIVILEGED_DEV \ >> | UBLK_F_CMD_IOCTL_ENCODE \ >> - | UBLK_F_USER_COPY) >> + | UBLK_F_USER_COPY \ >> + | UBLK_F_ZONED) >> >> /* All UBLK_PARAM_TYPE_* should be included here */ >> -#define UBLK_PARAM_TYPE_ALL (UBLK_PARAM_TYPE_BASIC | \ >> - UBLK_PARAM_TYPE_DISCARD | UBLK_PARAM_TYPE_DEVT) >> +#define UBLK_PARAM_TYPE_ALL \ >> + (UBLK_PARAM_TYPE_BASIC | UBLK_PARAM_TYPE_DISCARD | \ >> + UBLK_PARAM_TYPE_DEVT | UBLK_PARAM_TYPE_ZONED) >> >> struct ublk_rq_data { >> struct llist_node node; >> >> struct kref ref; >> + __u64 sector; >> + __u32 operation; >> + __u32 nr_sectors; >> }; >> >> struct ublk_uring_cmd_pdu { >> @@ -110,6 +115,11 @@ struct ublk_uring_cmd_pdu { >> */ >> #define UBLK_IO_FLAG_NEED_GET_DATA 0x08 >> >> +/* >> + * Set when IO is Zone Append >> + */ >> +#define UBLK_IO_FLAG_ZONE_APPEND 0x10 >> + >> struct ublk_io { >> /* userspace buffer address from io cmd */ >> __u64 addr; >> @@ -190,6 +200,198 @@ static inline bool ublk_dev_is_user_copy(const struct ublk_device *ub) >> return ub->dev_info.flags & UBLK_F_USER_COPY; >> } >> >> +static inline bool ublk_dev_is_zoned(const struct ublk_device *ub) >> +{ >> + return ub->dev_info.flags & UBLK_F_ZONED; >> +} >> + >> +static inline bool ublk_queue_is_zoned(struct ublk_queue *ubq) >> +{ >> + return ubq->flags & UBLK_F_ZONED; >> +} >> + >> +#ifdef CONFIG_BLK_DEV_ZONED >> + >> +static int ublk_get_nr_zones(const struct ublk_device *ub) >> +{ >> + const struct ublk_param_basic *p = &ub->params.basic; >> + >> + /* Zone size is a power of 2 */ >> + return p->dev_sectors >> ilog2(p->chunk_sectors); >> +} >> + >> +static int ublk_revalidate_disk_zones(struct ublk_device *ub) >> +{ >> + return blk_revalidate_disk_zones(ub->ub_disk, NULL); >> +} >> + >> +static int ublk_dev_param_zoned_validate(const struct ublk_device *ub) >> +{ >> + const struct ublk_param_zoned *p = &ub->params.zoned; >> + int nr_zones; >> + >> + if (!ublk_dev_is_zoned(ub)) >> + return -EINVAL; >> + >> + if (!p->max_zone_append_sectors) >> + return -EINVAL; >> + >> + nr_zones = ublk_get_nr_zones(ub); >> + >> + if (p->max_active_zones > nr_zones) >> + return -EINVAL; >> + >> + if (p->max_open_zones > nr_zones) >> + return -EINVAL; >> + >> + return 0; >> +} >> + >> +static int ublk_dev_param_zoned_apply(struct ublk_device *ub) >> +{ >> + const struct ublk_param_zoned *p = &ub->params.zoned; >> + >> + disk_set_zoned(ub->ub_disk, BLK_ZONED_HM); >> + blk_queue_required_elevator_features(ub->ub_disk->queue, >> + ELEVATOR_F_ZBD_SEQ_WRITE); >> + disk_set_max_active_zones(ub->ub_disk, p->max_active_zones); >> + disk_set_max_open_zones(ub->ub_disk, p->max_open_zones); >> + blk_queue_max_zone_append_sectors(ub->ub_disk->queue, p->max_zone_append_sectors); >> + >> + ub->ub_disk->nr_zones = ublk_get_nr_zones(ub); >> + >> + return 0; >> +} >> + >> +/* Based on virtblk_alloc_report_buffer */ >> +static void *ublk_alloc_report_buffer(struct ublk_device *ublk, >> + unsigned int nr_zones, size_t *buflen) >> +{ >> + struct request_queue *q = ublk->ub_disk->queue; >> + size_t bufsize; >> + void *buf; >> + >> + nr_zones = min_t(unsigned int, nr_zones, >> + ublk->ub_disk->nr_zones); >> + >> + bufsize = nr_zones * sizeof(struct blk_zone); >> + bufsize = >> + min_t(size_t, bufsize, queue_max_hw_sectors(q) << SECTOR_SHIFT); >> + bufsize = min_t(size_t, bufsize, queue_max_segments(q) << PAGE_SHIFT); > > 'bufsize' shouldn't related with queue_max_segments() given we don't > enable segment limit yet. Ok 👍 > >> + >> + while (bufsize >= sizeof(struct blk_zone)) { >> + buf = __vmalloc(bufsize, GFP_KERNEL | __GFP_NORETRY); >> + if (buf) { >> + *buflen = bufsize; >> + return buf; >> + } >> + bufsize >>= 1; >> + } >> + >> + *buflen = 0; >> + return NULL; >> +} >> + >> +static int ublk_report_zones(struct gendisk *disk, sector_t sector, >> + unsigned int nr_zones, report_zones_cb cb, void *data) >> +{ >> + struct ublk_device *ub = disk->private_data; >> + unsigned int zone_size_sectors = disk->queue->limits.chunk_sectors; >> + unsigned int first_zone = sector >> ilog2(zone_size_sectors); >> + unsigned int done_zones = 0; >> + unsigned int max_zones_per_request; >> + int ret; >> + struct blk_zone *buffer; >> + size_t buffer_length; >> + >> + nr_zones = min_t(unsigned int, ub->ub_disk->nr_zones - first_zone, >> + nr_zones); >> + >> + buffer = ublk_alloc_report_buffer(ub, nr_zones, &buffer_length); >> + if (!buffer) >> + return -ENOMEM; >> + >> + max_zones_per_request = buffer_length / sizeof(struct blk_zone); >> + >> + while (done_zones < nr_zones) { >> + unsigned int remaining_zones = nr_zones - done_zones; >> + unsigned int zones_in_request = >> + min_t(unsigned int, remaining_zones, max_zones_per_request); >> + struct request *req; >> + struct ublk_rq_data *pdu; >> + blk_status_t status; >> + >> + memset(buffer, 0, buffer_length); >> + >> + req = blk_mq_alloc_request(disk->queue, REQ_OP_DRV_IN, 0); >> + if (IS_ERR(req)) { >> + ret = PTR_ERR(req); >> + goto out; >> + } >> + >> + pdu = blk_mq_rq_to_pdu(req); >> + pdu->operation = UBLK_IO_OP_REPORT_ZONES; >> + pdu->sector = sector; >> + pdu->nr_sectors = remaining_zones * zone_size_sectors; > > pdu->nr_sectors will be set to ublksrv_io_desc->nr_sectors as part of > UAPI, I feel it is hard to understand to pass 'remaining_zones * zone_size_sectors', > probably it is fine to re-define as buffer size or requested > nr_blk_zone, or other ideas? This is the only place `pdu->nr_sectors` is assigned. We copy the value to `iod->nr_sectors` when we process the request. So I think that part is OK. However, it should be set to `zones_in_request`, not `remaining_zones`. Otherwise user space might try to write too much to the buffer and get confused when the write fails. > >> + >> + ret = blk_rq_map_kern(disk->queue, req, buffer, buffer_length, >> + GFP_KERNEL); >> + if (ret) { >> + blk_mq_free_request(req); >> + goto out; >> + } >> + >> + status = blk_execute_rq(req, 0); >> + ret = blk_status_to_errno(status); >> + blk_mq_free_request(req); >> + if (ret) >> + goto out; >> + >> + for (unsigned int i = 0; i < zones_in_request; i++) { >> + struct blk_zone *zone = buffer + i; >> + >> + /* A zero length zone means no more zones in this response */ >> + if (!zone->len) >> + break; >> + >> + ret = cb(zone, i, data); >> + if (ret) >> + goto out; >> + >> + done_zones++; >> + sector += zone_size_sectors; >> + >> + } >> + } >> + >> + ret = done_zones; >> + >> +out: >> + kvfree(buffer); >> + return ret; >> +} >> + >> +#else >> + >> +#define ublk_report_zones (NULL) >> + >> +static int ublk_dev_param_zoned_validate(const struct ublk_device *ub) >> +{ >> + return -EOPNOTSUPP; >> +} >> + >> +static int ublk_dev_param_zoned_apply(struct ublk_device *ub) >> +{ >> + return -EOPNOTSUPP; >> +} >> + >> +static int ublk_revalidate_disk_zones(struct ublk_device *ub) >> +{ >> + return 0; >> +} >> + >> +#endif >> + >> static inline void __ublk_complete_rq(struct request *req); >> static void ublk_complete_rq(struct kref *ref); >> >> @@ -232,7 +434,7 @@ static inline unsigned ublk_pos_to_tag(loff_t pos) >> UBLK_TAG_BITS_MASK; >> } >> >> -static void ublk_dev_param_basic_apply(struct ublk_device *ub) >> +static int ublk_dev_param_basic_apply(struct ublk_device *ub) >> { >> struct request_queue *q = ub->ub_disk->queue; >> const struct ublk_param_basic *p = &ub->params.basic; >> @@ -257,6 +459,8 @@ static void ublk_dev_param_basic_apply(struct ublk_device *ub) >> set_disk_ro(ub->ub_disk, true); >> >> set_capacity(ub->ub_disk, p->dev_sectors); >> + >> + return 0; >> } >> >> static void ublk_dev_param_discard_apply(struct ublk_device *ub) >> @@ -286,6 +490,9 @@ static int ublk_validate_params(const struct ublk_device *ub) >> >> if (p->max_sectors > (ub->dev_info.max_io_buf_bytes >> 9)) >> return -EINVAL; >> + >> + if (ublk_dev_is_zoned(ub) && !p->chunk_sectors) >> + return -EINVAL; >> } else >> return -EINVAL; >> >> @@ -304,19 +511,31 @@ static int ublk_validate_params(const struct ublk_device *ub) >> if (ub->params.types & UBLK_PARAM_TYPE_DEVT) >> return -EINVAL; >> >> + if (ub->params.types & UBLK_PARAM_TYPE_ZONED) >> + return ublk_dev_param_zoned_validate(ub); >> + else if (ublk_dev_is_zoned(ub)) >> + return -EINVAL; >> + >> return 0; >> } >> >> static int ublk_apply_params(struct ublk_device *ub) >> { >> + int ret; >> + >> if (!(ub->params.types & UBLK_PARAM_TYPE_BASIC)) >> return -EINVAL; >> >> - ublk_dev_param_basic_apply(ub); >> + ret = ublk_dev_param_basic_apply(ub); >> + if (ret) >> + return ret; >> >> if (ub->params.types & UBLK_PARAM_TYPE_DISCARD) >> ublk_dev_param_discard_apply(ub); >> >> + if (ub->params.types & UBLK_PARAM_TYPE_ZONED) >> + return ublk_dev_param_zoned_apply(ub); >> + >> return 0; >> } >> >> @@ -487,6 +706,7 @@ static const struct block_device_operations ub_fops = { >> .owner = THIS_MODULE, >> .open = ublk_open, >> .free_disk = ublk_free_disk, >> + .report_zones = ublk_report_zones, >> }; >> >> #define UBLK_MAX_PIN_PAGES 32 >> @@ -601,7 +821,8 @@ static inline bool ublk_need_map_req(const struct request *req) >> >> static inline bool ublk_need_unmap_req(const struct request *req) >> { >> - return ublk_rq_has_data(req) && req_op(req) == REQ_OP_READ; >> + return ublk_rq_has_data(req) && >> + (req_op(req) == REQ_OP_READ || req_op(req) == REQ_OP_DRV_IN); >> } >> >> static int ublk_map_io(const struct ublk_queue *ubq, const struct request *req, >> @@ -685,8 +906,14 @@ static blk_status_t ublk_setup_iod(struct ublk_queue *ubq, struct request *req) >> { >> struct ublksrv_io_desc *iod = ublk_get_iod(ubq, req->tag); >> struct ublk_io *io = &ubq->ios[req->tag]; >> + struct ublk_rq_data *pdu = blk_mq_rq_to_pdu(req); >> + enum req_op op = req_op(req); >> u32 ublk_op; >> >> + if (!ublk_queue_is_zoned(ubq) && >> + (op_is_zone_mgmt(op) || op == REQ_OP_ZONE_APPEND)) >> + return -EIO; >> + >> switch (req_op(req)) { >> case REQ_OP_READ: >> ublk_op = UBLK_IO_OP_READ; >> @@ -703,6 +930,37 @@ static blk_status_t ublk_setup_iod(struct ublk_queue *ubq, struct request *req) >> case REQ_OP_WRITE_ZEROES: >> ublk_op = UBLK_IO_OP_WRITE_ZEROES; >> break; >> + case REQ_OP_ZONE_OPEN: >> + ublk_op = UBLK_IO_OP_ZONE_OPEN; >> + break; >> + case REQ_OP_ZONE_CLOSE: >> + ublk_op = UBLK_IO_OP_ZONE_CLOSE; >> + break; >> + case REQ_OP_ZONE_FINISH: >> + ublk_op = UBLK_IO_OP_ZONE_FINISH; >> + break; >> + case REQ_OP_ZONE_RESET: >> + ublk_op = UBLK_IO_OP_ZONE_RESET; >> + break; >> + case REQ_OP_DRV_IN: >> + ublk_op = pdu->operation; >> + switch (ublk_op) { >> + case UBLK_IO_OP_REPORT_ZONES: >> + iod->op_flags = ublk_op | ublk_req_build_flags(req); >> + iod->nr_sectors = pdu->nr_sectors; >> + iod->start_sector = pdu->sector; >> + return BLK_STS_OK; >> + default: >> + return BLK_STS_IOERR; >> + } >> + case REQ_OP_ZONE_APPEND: >> + ublk_op = UBLK_IO_OP_ZONE_APPEND; >> + io->flags |= UBLK_IO_FLAG_ZONE_APPEND; >> + break; >> + case REQ_OP_ZONE_RESET_ALL: >> + case REQ_OP_DRV_OUT: >> + /* We do not support reset_all and drv_out */ >> + return BLK_STS_NOTSUPP; > > I'd suggest to move all zoned handling & the above check into one helper, > such as: > > default: > if (ublk_queue_is_zoned()) > return ublk_zoned_setup_iod(); > > Then zoned check can be avoided for other generic OPs, and zoned patch > conflict could be avoided usually. Alright 👍 Best regards, Andreas
