From: Stanley Zhang <stazhang@purestorage.com>
If the UBLK_PARAM_TYPE_INTEGRITY flag is set, validate the integrity
parameters and apply them to the blk_integrity limits.
UBLK_PARAM_TYPE_INTEGRITY requires CONFIG_BLK_DEV_INTEGRITY=y,
UBLK_F_USER_COPY, and metadata_size > 0. Reuse the block metadata ioctl
LBMD_PI_CAP_* and LBMD_PI_CSUM_* constants from the linux/fs.h UAPI
header for the flags and csum_type field values.
The struct ublk_param_integrity validations are based on the checks in
blk_validate_integrity_limits(). Any invalid parameters should be
rejected before being applied to struct blk_integrity.
Signed-off-by: Stanley Zhang <stazhang@purestorage.com>
[csander: add param validation]
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
---
drivers/block/ublk_drv.c | 92 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 91 insertions(+), 1 deletion(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 4da5d8ff1e1d..2893a9172220 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -42,10 +42,12 @@
#include <linux/mm.h>
#include <asm/page.h>
#include <linux/task_work.h>
#include <linux/namei.h>
#include <linux/kref.h>
+#include <linux/blk-integrity.h>
+#include <uapi/linux/fs.h>
#include <uapi/linux/ublk_cmd.h>
#define UBLK_MINORS (1U << MINORBITS)
#define UBLK_INVALID_BUF_IDX ((u16)-1)
@@ -81,11 +83,12 @@
/* 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 | UBLK_PARAM_TYPE_ZONED | \
- UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT)
+ UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT | \
+ UBLK_PARAM_TYPE_INTEGRITY)
struct ublk_uring_cmd_pdu {
/*
* Store requests in same batch temporarily for queuing them to
* daemon context.
@@ -613,10 +616,57 @@ 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);
}
+static int ublk_integrity_flags(u32 flags)
+{
+ int ret_flags = 0;
+
+ if (flags & LBMD_PI_CAP_INTEGRITY) {
+ flags &= ~LBMD_PI_CAP_INTEGRITY;
+ ret_flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
+ }
+ if (flags & LBMD_PI_CAP_REFTAG) {
+ flags &= ~LBMD_PI_CAP_REFTAG;
+ ret_flags |= BLK_INTEGRITY_REF_TAG;
+ }
+ return flags ? -EINVAL : ret_flags;
+}
+
+static int ublk_integrity_pi_tuple_size(u8 csum_type)
+{
+ switch (csum_type) {
+ case LBMD_PI_CSUM_NONE:
+ return 0;
+ case LBMD_PI_CSUM_IP:
+ case LBMD_PI_CSUM_CRC16_T10DIF:
+ return 8;
+ case LBMD_PI_CSUM_CRC64_NVME:
+ return 16;
+ default:
+ return -EINVAL;
+ }
+}
+
+static enum blk_integrity_checksum ublk_integrity_csum_type(u8 csum_type)
+{
+ switch (csum_type) {
+ case LBMD_PI_CSUM_NONE:
+ return BLK_INTEGRITY_CSUM_NONE;
+ case LBMD_PI_CSUM_IP:
+ return BLK_INTEGRITY_CSUM_IP;
+ case LBMD_PI_CSUM_CRC16_T10DIF:
+ return BLK_INTEGRITY_CSUM_CRC;
+ case LBMD_PI_CSUM_CRC64_NVME:
+ return BLK_INTEGRITY_CSUM_CRC64;
+ default:
+ WARN_ON_ONCE(1);
+ return BLK_INTEGRITY_CSUM_NONE;
+ }
+}
+
static int ublk_validate_params(const struct ublk_device *ub)
{
/* 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;
@@ -675,10 +725,35 @@ static int ublk_validate_params(const struct ublk_device *ub)
return -EINVAL;
if (p->max_segment_size < UBLK_MIN_SEGMENT_SIZE)
return -EINVAL;
}
+ if (ub->params.types & UBLK_PARAM_TYPE_INTEGRITY) {
+ const struct ublk_param_integrity *p = &ub->params.integrity;
+ int pi_tuple_size = ublk_integrity_pi_tuple_size(p->csum_type);
+ int flags = ublk_integrity_flags(p->flags);
+
+ if (!IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY))
+ return -EINVAL;
+ if (!ublk_dev_support_user_copy(ub))
+ return -EINVAL;
+ if (flags < 0)
+ return flags;
+ if (pi_tuple_size < 0)
+ return pi_tuple_size;
+ if (!p->metadata_size)
+ return -EINVAL;
+ if (p->csum_type == LBMD_PI_CSUM_NONE &&
+ (p->flags & LBMD_PI_CAP_REFTAG))
+ return -EINVAL;
+ if (p->pi_offset + pi_tuple_size > p->metadata_size)
+ return -EINVAL;
+ if (p->interval_exp < SECTOR_SHIFT ||
+ p->interval_exp > ub->params.basic.logical_bs_shift)
+ return -EINVAL;
+ }
+
return 0;
}
static void ublk_apply_params(struct ublk_device *ub)
{
@@ -2901,10 +2976,25 @@ static int ublk_ctrl_start_dev(struct ublk_device *ub,
lim.seg_boundary_mask = ub->params.seg.seg_boundary_mask;
lim.max_segment_size = ub->params.seg.max_segment_size;
lim.max_segments = ub->params.seg.max_segments;
}
+ if (ub->params.types & UBLK_PARAM_TYPE_INTEGRITY) {
+ const struct ublk_param_integrity *p = &ub->params.integrity;
+ int pi_tuple_size = ublk_integrity_pi_tuple_size(p->csum_type);
+
+ lim.integrity = (struct blk_integrity) {
+ .flags = ublk_integrity_flags(p->flags),
+ .csum_type = ublk_integrity_csum_type(p->csum_type),
+ .metadata_size = p->metadata_size,
+ .pi_offset = p->pi_offset,
+ .interval_exp = p->interval_exp,
+ .tag_size = p->tag_size,
+ .pi_tuple_size = pi_tuple_size,
+ };
+ }
+
if (wait_for_completion_interruptible(&ub->completion) != 0)
return -EINTR;
if (ub->ublksrv_tgid != ublksrv_pid)
return -EINVAL;
--
2.45.2On Tue, Dec 16, 2025 at 10:34:40PM -0700, Caleb Sander Mateos wrote:
> From: Stanley Zhang <stazhang@purestorage.com>
>
> If the UBLK_PARAM_TYPE_INTEGRITY flag is set, validate the integrity
> parameters and apply them to the blk_integrity limits.
> UBLK_PARAM_TYPE_INTEGRITY requires CONFIG_BLK_DEV_INTEGRITY=y,
> UBLK_F_USER_COPY, and metadata_size > 0. Reuse the block metadata ioctl
> LBMD_PI_CAP_* and LBMD_PI_CSUM_* constants from the linux/fs.h UAPI
> header for the flags and csum_type field values.
> The struct ublk_param_integrity validations are based on the checks in
> blk_validate_integrity_limits(). Any invalid parameters should be
> rejected before being applied to struct blk_integrity.
>
> Signed-off-by: Stanley Zhang <stazhang@purestorage.com>
> [csander: add param validation]
> Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
> ---
> drivers/block/ublk_drv.c | 92 +++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 91 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
> index 4da5d8ff1e1d..2893a9172220 100644
> --- a/drivers/block/ublk_drv.c
> +++ b/drivers/block/ublk_drv.c
> @@ -42,10 +42,12 @@
> #include <linux/mm.h>
> #include <asm/page.h>
> #include <linux/task_work.h>
> #include <linux/namei.h>
> #include <linux/kref.h>
> +#include <linux/blk-integrity.h>
> +#include <uapi/linux/fs.h>
> #include <uapi/linux/ublk_cmd.h>
>
> #define UBLK_MINORS (1U << MINORBITS)
>
> #define UBLK_INVALID_BUF_IDX ((u16)-1)
> @@ -81,11 +83,12 @@
>
> /* 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 | UBLK_PARAM_TYPE_ZONED | \
> - UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT)
> + UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT | \
> + UBLK_PARAM_TYPE_INTEGRITY)
>
> struct ublk_uring_cmd_pdu {
> /*
> * Store requests in same batch temporarily for queuing them to
> * daemon context.
> @@ -613,10 +616,57 @@ 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);
> }
>
> +static int ublk_integrity_flags(u32 flags)
> +{
> + int ret_flags = 0;
> +
> + if (flags & LBMD_PI_CAP_INTEGRITY) {
> + flags &= ~LBMD_PI_CAP_INTEGRITY;
> + ret_flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
> + }
> + if (flags & LBMD_PI_CAP_REFTAG) {
> + flags &= ~LBMD_PI_CAP_REFTAG;
> + ret_flags |= BLK_INTEGRITY_REF_TAG;
> + }
> + return flags ? -EINVAL : ret_flags;
> +}
> +
> +static int ublk_integrity_pi_tuple_size(u8 csum_type)
> +{
> + switch (csum_type) {
> + case LBMD_PI_CSUM_NONE:
> + return 0;
> + case LBMD_PI_CSUM_IP:
> + case LBMD_PI_CSUM_CRC16_T10DIF:
> + return 8;
> + case LBMD_PI_CSUM_CRC64_NVME:
> + return 16;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static enum blk_integrity_checksum ublk_integrity_csum_type(u8 csum_type)
> +{
> + switch (csum_type) {
> + case LBMD_PI_CSUM_NONE:
> + return BLK_INTEGRITY_CSUM_NONE;
> + case LBMD_PI_CSUM_IP:
> + return BLK_INTEGRITY_CSUM_IP;
> + case LBMD_PI_CSUM_CRC16_T10DIF:
> + return BLK_INTEGRITY_CSUM_CRC;
> + case LBMD_PI_CSUM_CRC64_NVME:
> + return BLK_INTEGRITY_CSUM_CRC64;
> + default:
> + WARN_ON_ONCE(1);
> + return BLK_INTEGRITY_CSUM_NONE;
> + }
> +}
> +
> static int ublk_validate_params(const struct ublk_device *ub)
> {
> /* 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;
> @@ -675,10 +725,35 @@ static int ublk_validate_params(const struct ublk_device *ub)
> return -EINVAL;
> if (p->max_segment_size < UBLK_MIN_SEGMENT_SIZE)
> return -EINVAL;
> }
>
> + if (ub->params.types & UBLK_PARAM_TYPE_INTEGRITY) {
> + const struct ublk_param_integrity *p = &ub->params.integrity;
> + int pi_tuple_size = ublk_integrity_pi_tuple_size(p->csum_type);
> + int flags = ublk_integrity_flags(p->flags);
> +
> + if (!IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY))
> + return -EINVAL;
> + if (!ublk_dev_support_user_copy(ub))
> + return -EINVAL;
UBLK_IO_F_INTEGRITY should be checked here, and ublk_dev_support_user_copy() can be
validated with UBLK_IO_F_INTEGRITY together in ublk_ctrl_add_dev(), so
mis-matched features can be failed earlier.
Same for IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY).
> + if (flags < 0)
> + return flags;
> + if (pi_tuple_size < 0)
> + return pi_tuple_size;
> + if (!p->metadata_size)
> + return -EINVAL;
blk_validate_integrity_limits() allows zero p->metadata_size with
LBMD_PI_CSUM_NONE, maybe document ublk's support for zero metadata_size & LBMD_PI_CSUM_NONE?
Thanks,
Ming
On Mon, Dec 22, 2025 at 9:47 AM Ming Lei <ming.lei@redhat.com> wrote:
>
> On Tue, Dec 16, 2025 at 10:34:40PM -0700, Caleb Sander Mateos wrote:
> > From: Stanley Zhang <stazhang@purestorage.com>
> >
> > If the UBLK_PARAM_TYPE_INTEGRITY flag is set, validate the integrity
> > parameters and apply them to the blk_integrity limits.
> > UBLK_PARAM_TYPE_INTEGRITY requires CONFIG_BLK_DEV_INTEGRITY=y,
> > UBLK_F_USER_COPY, and metadata_size > 0. Reuse the block metadata ioctl
> > LBMD_PI_CAP_* and LBMD_PI_CSUM_* constants from the linux/fs.h UAPI
> > header for the flags and csum_type field values.
> > The struct ublk_param_integrity validations are based on the checks in
> > blk_validate_integrity_limits(). Any invalid parameters should be
> > rejected before being applied to struct blk_integrity.
> >
> > Signed-off-by: Stanley Zhang <stazhang@purestorage.com>
> > [csander: add param validation]
> > Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
> > ---
> > drivers/block/ublk_drv.c | 92 +++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 91 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
> > index 4da5d8ff1e1d..2893a9172220 100644
> > --- a/drivers/block/ublk_drv.c
> > +++ b/drivers/block/ublk_drv.c
> > @@ -42,10 +42,12 @@
> > #include <linux/mm.h>
> > #include <asm/page.h>
> > #include <linux/task_work.h>
> > #include <linux/namei.h>
> > #include <linux/kref.h>
> > +#include <linux/blk-integrity.h>
> > +#include <uapi/linux/fs.h>
> > #include <uapi/linux/ublk_cmd.h>
> >
> > #define UBLK_MINORS (1U << MINORBITS)
> >
> > #define UBLK_INVALID_BUF_IDX ((u16)-1)
> > @@ -81,11 +83,12 @@
> >
> > /* 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 | UBLK_PARAM_TYPE_ZONED | \
> > - UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT)
> > + UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT | \
> > + UBLK_PARAM_TYPE_INTEGRITY)
> >
> > struct ublk_uring_cmd_pdu {
> > /*
> > * Store requests in same batch temporarily for queuing them to
> > * daemon context.
> > @@ -613,10 +616,57 @@ 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);
> > }
> >
> > +static int ublk_integrity_flags(u32 flags)
> > +{
> > + int ret_flags = 0;
> > +
> > + if (flags & LBMD_PI_CAP_INTEGRITY) {
> > + flags &= ~LBMD_PI_CAP_INTEGRITY;
> > + ret_flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
> > + }
> > + if (flags & LBMD_PI_CAP_REFTAG) {
> > + flags &= ~LBMD_PI_CAP_REFTAG;
> > + ret_flags |= BLK_INTEGRITY_REF_TAG;
> > + }
> > + return flags ? -EINVAL : ret_flags;
> > +}
> > +
> > +static int ublk_integrity_pi_tuple_size(u8 csum_type)
> > +{
> > + switch (csum_type) {
> > + case LBMD_PI_CSUM_NONE:
> > + return 0;
> > + case LBMD_PI_CSUM_IP:
> > + case LBMD_PI_CSUM_CRC16_T10DIF:
> > + return 8;
> > + case LBMD_PI_CSUM_CRC64_NVME:
> > + return 16;
> > + default:
> > + return -EINVAL;
> > + }
> > +}
> > +
> > +static enum blk_integrity_checksum ublk_integrity_csum_type(u8 csum_type)
> > +{
> > + switch (csum_type) {
> > + case LBMD_PI_CSUM_NONE:
> > + return BLK_INTEGRITY_CSUM_NONE;
> > + case LBMD_PI_CSUM_IP:
> > + return BLK_INTEGRITY_CSUM_IP;
> > + case LBMD_PI_CSUM_CRC16_T10DIF:
> > + return BLK_INTEGRITY_CSUM_CRC;
> > + case LBMD_PI_CSUM_CRC64_NVME:
> > + return BLK_INTEGRITY_CSUM_CRC64;
> > + default:
> > + WARN_ON_ONCE(1);
> > + return BLK_INTEGRITY_CSUM_NONE;
> > + }
> > +}
> > +
> > static int ublk_validate_params(const struct ublk_device *ub)
> > {
> > /* 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;
> > @@ -675,10 +725,35 @@ static int ublk_validate_params(const struct ublk_device *ub)
> > return -EINVAL;
> > if (p->max_segment_size < UBLK_MIN_SEGMENT_SIZE)
> > return -EINVAL;
> > }
> >
> > + if (ub->params.types & UBLK_PARAM_TYPE_INTEGRITY) {
> > + const struct ublk_param_integrity *p = &ub->params.integrity;
> > + int pi_tuple_size = ublk_integrity_pi_tuple_size(p->csum_type);
> > + int flags = ublk_integrity_flags(p->flags);
> > +
> > + if (!IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY))
> > + return -EINVAL;
> > + if (!ublk_dev_support_user_copy(ub))
> > + return -EINVAL;
>
> UBLK_IO_F_INTEGRITY should be checked here, and ublk_dev_support_user_copy() can be
> validated with UBLK_IO_F_INTEGRITY together in ublk_ctrl_add_dev(), so
> mis-matched features can be failed earlier.
I'm not sure what you mean. UBLK_IO_F_INTEGRITY is a per-I/O flag set
in struct ublksrv_io_desc's op_flags field. Are you suggesting adding
a separate feature flag for integrity? I can do that, but I didn't
originally because none of the other UBLK_PARAM_TYPE_* flags have
associated features.
>
> Same for IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY).
>
> > + if (flags < 0)
> > + return flags;
> > + if (pi_tuple_size < 0)
> > + return pi_tuple_size;
> > + if (!p->metadata_size)
> > + return -EINVAL;
>
> blk_validate_integrity_limits() allows zero p->metadata_size with
> LBMD_PI_CSUM_NONE, maybe document ublk's support for zero metadata_size & LBMD_PI_CSUM_NONE?
Sure, I can mention that UBLK_PARAM_TYPE_INTEGRITY requires a nonzero
metadata size. Would you prefer that metadata_size == 0 be supported?
It would be a bit more code, but certainly possible.
Thanks,
Caleb
On Mon, Dec 22, 2025 at 10:35:27AM -0500, Caleb Sander Mateos wrote:
> On Mon, Dec 22, 2025 at 9:47 AM Ming Lei <ming.lei@redhat.com> wrote:
> >
> > On Tue, Dec 16, 2025 at 10:34:40PM -0700, Caleb Sander Mateos wrote:
> > > From: Stanley Zhang <stazhang@purestorage.com>
> > >
> > > If the UBLK_PARAM_TYPE_INTEGRITY flag is set, validate the integrity
> > > parameters and apply them to the blk_integrity limits.
> > > UBLK_PARAM_TYPE_INTEGRITY requires CONFIG_BLK_DEV_INTEGRITY=y,
> > > UBLK_F_USER_COPY, and metadata_size > 0. Reuse the block metadata ioctl
> > > LBMD_PI_CAP_* and LBMD_PI_CSUM_* constants from the linux/fs.h UAPI
> > > header for the flags and csum_type field values.
> > > The struct ublk_param_integrity validations are based on the checks in
> > > blk_validate_integrity_limits(). Any invalid parameters should be
> > > rejected before being applied to struct blk_integrity.
> > >
> > > Signed-off-by: Stanley Zhang <stazhang@purestorage.com>
> > > [csander: add param validation]
> > > Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
> > > ---
> > > drivers/block/ublk_drv.c | 92 +++++++++++++++++++++++++++++++++++++++-
> > > 1 file changed, 91 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
> > > index 4da5d8ff1e1d..2893a9172220 100644
> > > --- a/drivers/block/ublk_drv.c
> > > +++ b/drivers/block/ublk_drv.c
> > > @@ -42,10 +42,12 @@
> > > #include <linux/mm.h>
> > > #include <asm/page.h>
> > > #include <linux/task_work.h>
> > > #include <linux/namei.h>
> > > #include <linux/kref.h>
> > > +#include <linux/blk-integrity.h>
> > > +#include <uapi/linux/fs.h>
> > > #include <uapi/linux/ublk_cmd.h>
> > >
> > > #define UBLK_MINORS (1U << MINORBITS)
> > >
> > > #define UBLK_INVALID_BUF_IDX ((u16)-1)
> > > @@ -81,11 +83,12 @@
> > >
> > > /* 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 | UBLK_PARAM_TYPE_ZONED | \
> > > - UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT)
> > > + UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT | \
> > > + UBLK_PARAM_TYPE_INTEGRITY)
> > >
> > > struct ublk_uring_cmd_pdu {
> > > /*
> > > * Store requests in same batch temporarily for queuing them to
> > > * daemon context.
> > > @@ -613,10 +616,57 @@ 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);
> > > }
> > >
> > > +static int ublk_integrity_flags(u32 flags)
> > > +{
> > > + int ret_flags = 0;
> > > +
> > > + if (flags & LBMD_PI_CAP_INTEGRITY) {
> > > + flags &= ~LBMD_PI_CAP_INTEGRITY;
> > > + ret_flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
> > > + }
> > > + if (flags & LBMD_PI_CAP_REFTAG) {
> > > + flags &= ~LBMD_PI_CAP_REFTAG;
> > > + ret_flags |= BLK_INTEGRITY_REF_TAG;
> > > + }
> > > + return flags ? -EINVAL : ret_flags;
> > > +}
> > > +
> > > +static int ublk_integrity_pi_tuple_size(u8 csum_type)
> > > +{
> > > + switch (csum_type) {
> > > + case LBMD_PI_CSUM_NONE:
> > > + return 0;
> > > + case LBMD_PI_CSUM_IP:
> > > + case LBMD_PI_CSUM_CRC16_T10DIF:
> > > + return 8;
> > > + case LBMD_PI_CSUM_CRC64_NVME:
> > > + return 16;
> > > + default:
> > > + return -EINVAL;
> > > + }
> > > +}
> > > +
> > > +static enum blk_integrity_checksum ublk_integrity_csum_type(u8 csum_type)
> > > +{
> > > + switch (csum_type) {
> > > + case LBMD_PI_CSUM_NONE:
> > > + return BLK_INTEGRITY_CSUM_NONE;
> > > + case LBMD_PI_CSUM_IP:
> > > + return BLK_INTEGRITY_CSUM_IP;
> > > + case LBMD_PI_CSUM_CRC16_T10DIF:
> > > + return BLK_INTEGRITY_CSUM_CRC;
> > > + case LBMD_PI_CSUM_CRC64_NVME:
> > > + return BLK_INTEGRITY_CSUM_CRC64;
> > > + default:
> > > + WARN_ON_ONCE(1);
> > > + return BLK_INTEGRITY_CSUM_NONE;
> > > + }
> > > +}
> > > +
> > > static int ublk_validate_params(const struct ublk_device *ub)
> > > {
> > > /* 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;
> > > @@ -675,10 +725,35 @@ static int ublk_validate_params(const struct ublk_device *ub)
> > > return -EINVAL;
> > > if (p->max_segment_size < UBLK_MIN_SEGMENT_SIZE)
> > > return -EINVAL;
> > > }
> > >
> > > + if (ub->params.types & UBLK_PARAM_TYPE_INTEGRITY) {
> > > + const struct ublk_param_integrity *p = &ub->params.integrity;
> > > + int pi_tuple_size = ublk_integrity_pi_tuple_size(p->csum_type);
> > > + int flags = ublk_integrity_flags(p->flags);
> > > +
> > > + if (!IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY))
> > > + return -EINVAL;
> > > + if (!ublk_dev_support_user_copy(ub))
> > > + return -EINVAL;
> >
> > UBLK_IO_F_INTEGRITY should be checked here, and ublk_dev_support_user_copy() can be
> > validated with UBLK_IO_F_INTEGRITY together in ublk_ctrl_add_dev(), so
> > mis-matched features can be failed earlier.
>
> I'm not sure what you mean. UBLK_IO_F_INTEGRITY is a per-I/O flag set
I misread it as feature flag of `UBLK_F_INTEGRITY`...
> in struct ublksrv_io_desc's op_flags field. Are you suggesting adding
> a separate feature flag for integrity? I can do that, but I didn't
> originally because none of the other UBLK_PARAM_TYPE_* flags have
> associated features.
oops, you don't define feature flag of UBLK_F_INTEGRITY, then how can
userspace know UBLK INTEGRITY is supported by driver?
With UBLK_F_INTEGRITY you can run early check in ublk_ctrl_add_dev() for:
- dependency on user copy
- if kernel enables CONFIG_BLK_DEV_INTEGRITY
>
> >
> > Same for IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY).
> >
> > > + if (flags < 0)
> > > + return flags;
> > > + if (pi_tuple_size < 0)
> > > + return pi_tuple_size;
> > > + if (!p->metadata_size)
> > > + return -EINVAL;
> >
> > blk_validate_integrity_limits() allows zero p->metadata_size with
> > LBMD_PI_CSUM_NONE, maybe document ublk's support for zero metadata_size & LBMD_PI_CSUM_NONE?
>
> Sure, I can mention that UBLK_PARAM_TYPE_INTEGRITY requires a nonzero
> metadata size. Would you prefer that metadata_size == 0 be supported?
> It would be a bit more code, but certainly possible.
It can be started with less feature/functions, and can be extended in future.
Thanks,
Ming
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