Re: [PATCH v4 4/4] ublk: add zone append

From: aravind . ramesh
Date: Fri Jun 30 2023 - 06:37:15 EST


From: Andreas Hindborg <a.hindborg@xxxxxxxxxxx <mailto:a.hindborg@xxxxxxxxxxx>>


Add zone append feature to ublk. This feature uses the `addr` field of `struct

checkpatch.pl warns on the keeping the line within 75 characters.
WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)

ublksrv_io_cmd`. Therefore ublk must be used with the user copy
feature (UBLK_F_USER_COPY) for zone append to be available. Without this
feature, ublk will fail zone append requests.


Suggested-by: Ming Lei <ming.lei@xxxxxxxxxx <mailto:ming.lei@xxxxxxxxxx>>
Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxxx
<mailto:a.hindborg@xxxxxxxxxxx>>
---
drivers/block/ublk_drv-zoned.c | 11 +++++++++
drivers/block/ublk_drv.c | 43 ++++++++++++++++++++++++++++++----
drivers/block/ublk_drv.h | 1 +
include/uapi/linux/ublk_cmd.h | 3 ++-
4 files changed, 52 insertions(+), 6 deletions(-)


diff --git a/drivers/block/ublk_drv-zoned.c b/drivers/block/ublk_drv-zoned.c
index ea86bf4b3681..007e8fc7ff25 100644
--- a/drivers/block/ublk_drv-zoned.c
+++ b/drivers/block/ublk_drv-zoned.c
@@ -16,6 +16,16 @@ void ublk_set_nr_zones(struct ublk_device *ub)
ub->ub_disk->nr_zones = p->dev_sectors / p->chunk_sectors;
}


+int ublk_dev_param_zoned_validate(const struct ublk_device *ub)
+{
+ const struct ublk_param_zoned *p = &ub->params.zoned;
+
+ if (! p->max_zone_append_sectors)

checkpatch.pl errors out here
ERROR: space prohibited after that '!' (ctx:BxW)
if (!p->max_zone_append_sectors)

+ return -EINVAL;
+
+ return 0;
+}
+
void ublk_dev_param_zoned_apply(struct ublk_device *ub)
{
const struct ublk_param_zoned *p = &ub->params.zoned;
@@ -23,6 +33,7 @@ void ublk_dev_param_zoned_apply(struct ublk_device *ub)
if (ub->dev_info.flags & UBLK_F_ZONED) {
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);
}
}


diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 88fa39853c61..6a949669b47e 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -107,6 +107,11 @@ 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;
@@ -230,6 +235,8 @@ static void ublk_dev_param_discard_apply(struct
ublk_device *ub)


static int ublk_validate_params(const struct ublk_device *ub)
{
+ int ret = 0;
+
/* basic param is the only one which must be set */
if (ub->params.types & UBLK_PARAM_TYPE_BASIC) {
const struct ublk_param_basic *p = &ub->params.basic;
@@ -260,6 +267,13 @@ static int ublk_validate_params(const struct
ublk_device *ub)
if (ub->params.types & UBLK_PARAM_TYPE_DEVT)
return -EINVAL;


+ if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
+ (ub->params.types & UBLK_PARAM_TYPE_ZONED)) {
+ ret = ublk_dev_param_zoned_validate(ub);
+ if (ret)
+ return ret;
+ }
+
return 0;
}


@@ -690,6 +704,11 @@ static blk_status_t ublk_setup_iod(struct
ublk_queue *ubq, struct request *req)
return BLK_STS_IOERR;
}
case REQ_OP_ZONE_APPEND:
+ if (!(ubq->dev->dev_info.flags & UBLK_F_USER_COPY))
+ return BLK_STS_IOERR;
+ 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 zone append or reset_all yet */
@@ -1112,6 +1131,12 @@ static void ublk_commit_completion(struct
ublk_device *ub,
/* find the io request and complete */
req = blk_mq_tag_to_rq(ub->tag_set.tags[qid], tag);


+ if (IS_ENABLED(CONFIG_BLK_DEV_ZONED)) {
+ if (io->flags & UBLK_IO_FLAG_ZONE_APPEND)
+ req->__sector = ub_cmd->addr;
+ io->flags &= ~UBLK_IO_FLAG_ZONE_APPEND;
+ }
+
if (req && likely(!blk_should_fake_timeout(req->q)))
ublk_put_req_ref(ubq, req);
}
@@ -1411,7 +1436,8 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
^ (_IOC_NR(cmd_op) == UBLK_IO_NEED_GET_DATA))
goto out;


- if (ublk_support_user_copy(ubq) && ub_cmd->addr) {
+ if (ublk_support_user_copy(ubq) &&
+ !(io->flags & UBLK_IO_FLAG_ZONE_APPEND) && ub_cmd->addr) {
ret = -EINVAL;
goto out;
}
@@ -1534,11 +1560,14 @@ static inline bool ublk_check_ubuf_dir(const
struct request *req,
int ubuf_dir)
{
/* copy ubuf to request pages */
- if (req_op(req) == REQ_OP_READ && ubuf_dir == ITER_SOURCE)
+ if ((req_op(req) == REQ_OP_READ || req_op(req) == REQ_OP_DRV_IN) &&
+ ubuf_dir == ITER_SOURCE)
return true;


/* copy request pages to ubuf */
- if (req_op(req) == REQ_OP_WRITE && ubuf_dir == ITER_DEST)
+ if ((req_op(req) == REQ_OP_WRITE ||
+ req_op(req) == REQ_OP_ZONE_APPEND) &&
+ ubuf_dir == ITER_DEST)
return true;


return false;
@@ -1867,6 +1896,12 @@ static int ublk_ctrl_start_dev(struct
ublk_device *ub, struct io_uring_cmd *cmd)
ub->dev_info.ublksrv_pid = ublksrv_pid;
ub->ub_disk = disk;


+ ub->dev_info.state = UBLK_S_DEV_LIVE;
+ if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
+ ub->dev_info.flags & UBLK_F_ZONED) {
+ disk_set_zoned(disk, BLK_ZONED_HM);
+ }
+
ret = ublk_apply_params(ub);
if (ret)
goto out_put_disk;
@@ -1877,7 +1912,6 @@ static int ublk_ctrl_start_dev(struct
ublk_device *ub, struct io_uring_cmd *cmd)


if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
ub->dev_info.flags & UBLK_F_ZONED) {
- disk_set_zoned(disk, BLK_ZONED_HM);
blk_queue_required_elevator_features(disk->queue, ELEVATOR_F_ZBD_SEQ_WRITE);
ret = ublk_revalidate_disk_zones(disk);
if (ret)
@@ -1885,7 +1919,6 @@ static int ublk_ctrl_start_dev(struct
ublk_device *ub, struct io_uring_cmd *cmd)
}


get_device(&ub->cdev_dev);
- ub->dev_info.state = UBLK_S_DEV_LIVE;
ret = add_disk(disk);
if (ret) {
/*
diff --git a/drivers/block/ublk_drv.h b/drivers/block/ublk_drv.h
index 7242430fd6b9..f55e1c25531d 100644
--- a/drivers/block/ublk_drv.h
+++ b/drivers/block/ublk_drv.h
@@ -56,6 +56,7 @@ struct ublk_rq_data {
};


void ublk_set_nr_zones(struct ublk_device *ub);
+int ublk_dev_param_zoned_validate(const struct ublk_device *ub);
void ublk_dev_param_zoned_apply(struct ublk_device *ub);
int ublk_revalidate_disk_zones(struct gendisk *disk);


diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h
index 436525afffe8..4b6ad0b28598 100644
--- a/include/uapi/linux/ublk_cmd.h
+++ b/include/uapi/linux/ublk_cmd.h
@@ -351,7 +351,8 @@ struct ublk_param_devt {
struct ublk_param_zoned {
__u32 max_open_zones;
__u32 max_active_zones;
- __u8 reserved[24];
+ __u32 max_zone_append_sectors;
+ __u8 reserved[20];
};


struct ublk_params {

Regards,
Aravind