From: Stanley Zhang stazhang@purestorage.com
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 stazhang@purestorage.com [csander: drop redundant pi_tuple_size field, use block metadata UAPI constants, add param validation] Signed-off-by: Caleb Sander Mateos csander@purestorage.com --- 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..2f9316febf83 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]; +}; + struct ublk_params { /* * Total length of parameters, userspace has to set 'len' for both * SET_PARAMS and GET_PARAMS command, and driver may update len * if two sides use different version of 'ublk_params', same with @@ -612,16 +628,18 @@ struct ublk_params { #define UBLK_PARAM_TYPE_DISCARD (1 << 1) #define UBLK_PARAM_TYPE_DEVT (1 << 2) #define UBLK_PARAM_TYPE_ZONED (1 << 3) #define UBLK_PARAM_TYPE_DMA_ALIGN (1 << 4) #define UBLK_PARAM_TYPE_SEGMENT (1 << 5) +#define UBLK_PARAM_TYPE_INTEGRITY (1 << 6) /* requires UBLK_F_INTEGRITY */ __u32 types; /* types of parameter included */
struct ublk_param_basic basic; struct ublk_param_discard discard; struct ublk_param_devt devt; struct ublk_param_zoned zoned; struct ublk_param_dma_align dma; struct ublk_param_segment seg; + struct ublk_param_integrity integrity; };
#endif