diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 539eada32861..222a0341913f 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -2343,6 +2343,21 @@ static int ublk_ctrl_end_recovery(struct ublk_device *ub, return ret; } +static int ublk_ctrl_get_features(struct io_uring_cmd *cmd) +{ + const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe); + void __user *argp = (void __user *)(unsigned long)header->addr; + u64 features = UBLK_F_ALL & ~UBLK_F_SUPPORT_ZERO_COPY; + + if (header->len != UBLK_FEATURES_LEN || !header->addr) + return -EINVAL; + + if (copy_to_user(argp, &features, UBLK_FEATURES_LEN)) + return -EFAULT; + + return 0; +} + /* * All control commands are sent via /dev/ublk-control, so we have to check * the destination device's permission @@ -2423,6 +2438,7 @@ static int ublk_ctrl_uring_cmd_permission(struct ublk_device *ub, case UBLK_CMD_GET_DEV_INFO2: case UBLK_CMD_GET_QUEUE_AFFINITY: case UBLK_CMD_GET_PARAMS: + case (_IOC_NR(UBLK_U_CMD_GET_FEATURES)): mask = MAY_READ; break; case UBLK_CMD_START_DEV: @@ -2472,6 +2488,11 @@ static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd, if (ret) goto out; + if (cmd_op == UBLK_U_CMD_GET_FEATURES) { + ret = ublk_ctrl_get_features(cmd); + goto out; + } + if (_IOC_NR(cmd_op) != UBLK_CMD_ADD_DEV) { ret = -ENODEV; ub = ublk_get_device_from_id(header->dev_id); diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h index 54b5b0aeefca..4b8558db90e1 100644 --- a/include/uapi/linux/ublk_cmd.h +++ b/include/uapi/linux/ublk_cmd.h @@ -47,6 +47,14 @@ _IOWR('u', UBLK_CMD_END_USER_RECOVERY, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_GET_DEV_INFO2 \ _IOR('u', UBLK_CMD_GET_DEV_INFO2, struct ublksrv_ctrl_cmd) +#define UBLK_U_CMD_GET_FEATURES \ + _IOR('u', 0x13, struct ublksrv_ctrl_cmd) + +/* + * 64bits are enough now, and it should be easy to extend in case of + * running out of feature flags + */ +#define UBLK_FEATURES_LEN 8 /* * IO commands, issued by ublk server, and handled by ublk driver.