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