On Mon, Jan 05, 2026 at 05:57:35PM -0700, Caleb Sander Mateos wrote: > From: Stanley Zhang <[email protected]> > > Add a feature flag UBLK_F_INTEGRITY for a ublk server to request > integrity/metadata support when creating a ublk device. The ublk server > can also check for the feature flag on the created device or the result > of UBLK_U_CMD_GET_FEATURES to tell if the ublk driver supports it. > UBLK_F_INTEGRITY requires UBLK_F_USER_COPY, as user copy is the only > data copy mode initially supported for integrity data. > Add UBLK_PARAM_TYPE_INTEGRITY and struct ublk_param_integrity to struct > ublk_params to specify the integrity params of a ublk device. > UBLK_PARAM_TYPE_INTEGRITY requires UBLK_F_INTEGRITY and a nonzero > metadata_size. The LBMD_PI_CAP_* and LBMD_PI_CSUM_* values from the > linux/fs.h UAPI header are used for the flags and csum_type fields. > If the UBLK_PARAM_TYPE_INTEGRITY flag is set, validate the integrity > parameters and apply them to the blk_integrity limits. > 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 <[email protected]> > [csander: drop redundant pi_tuple_size field, use block metadata UAPI > constants, add param validation] > Signed-off-by: Caleb Sander Mateos <[email protected]> > --- > drivers/block/ublk_drv.c | 94 ++++++++++++++++++++++++++++++++++- > include/uapi/linux/ublk_cmd.h | 18 +++++++ > 2 files changed, 111 insertions(+), 1 deletion(-) > > diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c > index 8e3da9b2b93a..066c6ae062a0 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. > @@ -628,10 +631,57 @@ 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; > @@ -690,10 +740,33 @@ 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 (!(ub->dev_info.flags & UBLK_F_INTEGRITY)) > + 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) > { > @@ -2941,10 +3014,25 @@ 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; > @@ -3131,10 +3219,14 @@ static int ublk_ctrl_add_dev(const struct > ublksrv_ctrl_cmd *header) > if (info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY | > UBLK_F_AUTO_BUF_REG)) > return -EINVAL; > } > > + /* User copy is required to access integrity buffer */ > + if (info.flags & UBLK_F_INTEGRITY && !(info.flags & UBLK_F_USER_COPY)) > + return -EINVAL; > + > /* the created device is always owned by current user */ > ublk_store_owner_uid_gid(&info.owner_uid, &info.owner_gid); > > if (header->dev_id != info.dev_id) { > pr_warn("%s: dev id not match %u %u\n", > diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h > index ec77dabba45b..a54c47832fa2 100644 > --- a/include/uapi/linux/ublk_cmd.h > +++ b/include/uapi/linux/ublk_cmd.h > @@ -309,10 +309,16 @@ > * the I/O's daemon task. The q_id and tag of the registered buffer are > required > * in UBLK_U_IO_UNREGISTER_IO_BUF's ublksrv_io_cmd. > */ > #define UBLK_F_BUF_REG_OFF_DAEMON (1ULL << 14) > > +/* > + * ublk device supports requests with integrity/metadata buffer. > + * Requires UBLK_F_USER_COPY. > + */ > +#define UBLK_F_INTEGRITY (1ULL << 16) > + > /* device state */ > #define UBLK_S_DEV_DEAD 0 > #define UBLK_S_DEV_LIVE 1 > #define UBLK_S_DEV_QUIESCED 2 > #define UBLK_S_DEV_FAIL_IO 3 > @@ -598,10 +604,20 @@ struct ublk_param_segment { > __u32 max_segment_size; > __u16 max_segments; > __u8 pad[2]; > }; > > +struct ublk_param_integrity { > + __u32 flags; /* LBMD_PI_CAP_* from linux/fs.h */ > + __u8 interval_exp; > + __u8 metadata_size; /* UBLK_PARAM_TYPE_INTEGRITY requires nonzero */ > + __u8 pi_offset; > + __u8 csum_type; /* LBMD_PI_CSUM_* from linux/fs.h */ > + __u8 tag_size; > + __u8 pad[7]; > +};
Looks max_integrity_segments is missed, otherwise this patch is fine for me. Thanks, Ming
