s390/uvdevice: Add info IOCTL (ea9d9716) · Commits · EulixOS / Software / Kernel

arch/s390/include/uapi/asm/uvdevice.h

+41 −1

Original line number	Diff line number	Diff line
		@@ -32,6 +32,33 @@ struct uvio_attest {
		__u16 reserved136; /* 0x0136 */
		};

		/**
		* uvio_uvdev_info - Information of supported functions
		* @supp_uvio_cmds - supported IOCTLs by this device
		* @supp_uv_cmds - supported UVCs corresponding to the IOCTL
		*
		* UVIO request to get information about supported request types by this
		* uvdevice and the Ultravisor. Everything is output. Bits are in LSB0
		* ordering. If the bit is set in both, @supp_uvio_cmds and @supp_uv_cmds, the
		* uvdevice and the Ultravisor support that call.
		*
		* Note that bit 0 (UVIO_IOCTL_UVDEV_INFO_NR) is always zero for `supp_uv_cmds`
		* as there is no corresponding UV-call.
		*/
		struct uvio_uvdev_info {
		/*
		* If bit `n` is set, this device supports the IOCTL with nr `n`.
		*/
		__u64 supp_uvio_cmds;
		/*
		* If bit `n` is set, the Ultravisor(UV) supports the UV-call
		* corresponding to the IOCTL with nr `n` in the calling contextx (host
		* or guest). The value is only valid if the corresponding bit in
		* @supp_uvio_cmds is set as well.
		*/
		__u64 supp_uv_cmds;
		};

		/*
		* The following max values define an upper length for the IOCTL in/out buffers.
		* However, they do not represent the maximum the Ultravisor allows which is
		@@ -46,6 +73,19 @@ struct uvio_attest {
		#define UVIO_DEVICE_NAME "uv"
		#define UVIO_TYPE_UVC 'u'

		#define UVIO_IOCTL_ATT _IOWR(UVIO_TYPE_UVC, 0x01, struct uvio_ioctl_cb)
		enum UVIO_IOCTL_NR {
		UVIO_IOCTL_UVDEV_INFO_NR = 0x00,
		UVIO_IOCTL_ATT_NR,
		/* must be the last entry */
		UVIO_IOCTL_NUM_IOCTLS
		};

		#define UVIO_IOCTL(nr) _IOWR(UVIO_TYPE_UVC, nr, struct uvio_ioctl_cb)
		#define UVIO_IOCTL_UVDEV_INFO UVIO_IOCTL(UVIO_IOCTL_UVDEV_INFO_NR)
		#define UVIO_IOCTL_ATT UVIO_IOCTL(UVIO_IOCTL_ATT_NR)

		#define UVIO_SUPP_CALL(nr) (1ULL << (nr))
		#define UVIO_SUPP_UDEV_INFO UVIO_SUPP_CALL(UVIO_IOCTL_UDEV_INFO_NR)
		#define UVIO_SUPP_ATT UVIO_SUPP_CALL(UVIO_IOCTL_ATT_NR)

		#endif /* __S390_ASM_UVDEVICE_H */

drivers/s390/char/Kconfig

+1 −1

Original line number	Diff line number	Diff line
		@@ -96,7 +96,7 @@ config SCLP_OFB
		config S390_UV_UAPI
		def_tristate m
		prompt "Ultravisor userspace API"
		depends on S390
		depends on S390 && (KVM \|\| PROTECTED_VIRTUALIZATION_GUEST)
		help
		Selecting exposes parts of the UV interface to userspace
		by providing a misc character device at /dev/uv.

drivers/s390/char/uvdevice.c

+70 −7

Original line number	Diff line number	Diff line
		@@ -32,6 +32,52 @@
		#include <asm/uvdevice.h>
		#include <asm/uv.h>

		#define BIT_UVIO_INTERNAL U32_MAX
		/* Mapping from IOCTL-nr to UVC-bit */
		static const u32 ioctl_nr_to_uvc_bit[] __initconst = {
		[UVIO_IOCTL_UVDEV_INFO_NR] = BIT_UVIO_INTERNAL,
		[UVIO_IOCTL_ATT_NR] = BIT_UVC_CMD_RETR_ATTEST,
		};

		static_assert(ARRAY_SIZE(ioctl_nr_to_uvc_bit) == UVIO_IOCTL_NUM_IOCTLS);

		static struct uvio_uvdev_info uvdev_info = {
		.supp_uvio_cmds = GENMASK_ULL(UVIO_IOCTL_NUM_IOCTLS - 1, 0),
		};

		static void __init set_supp_uv_cmds(unsigned long *supp_uv_cmds)
		{
		int i;

		for (i = 0; i < UVIO_IOCTL_NUM_IOCTLS; i++) {
		if (ioctl_nr_to_uvc_bit[i] == BIT_UVIO_INTERNAL)
		continue;
		if (!test_bit_inv(ioctl_nr_to_uvc_bit[i], uv_info.inst_calls_list))
		continue;
		__set_bit(i, supp_uv_cmds);
		}
		}

		/**
		* uvio_uvdev_info() - get information about the uvdevice
		*
		* @uv_ioctl: ioctl control block
		*
		* Lists all IOCTLs that are supported by this uvdevice
		*/
		static int uvio_uvdev_info(struct uvio_ioctl_cb *uv_ioctl)
		{
		void __user user_buf_arg = (void __user )uv_ioctl->argument_addr;

		if (uv_ioctl->argument_len < sizeof(uvdev_info))
		return -EINVAL;
		if (copy_to_user(user_buf_arg, &uvdev_info, sizeof(uvdev_info)))
		return -EFAULT;

		uv_ioctl->uv_rc = UVC_RC_EXECUTED;
		return 0;
		}

		static int uvio_build_uvcb_attest(struct uv_cb_attest uvcb_attest, u8 arcb,
		u8 meas, u8 add_data, struct uvio_attest *uvio_attest)
		{
		@@ -185,8 +231,19 @@ static int uvio_attestation(struct uvio_ioctl_cb *uv_ioctl)
		return ret;
		}

		static int uvio_copy_and_check_ioctl(struct uvio_ioctl_cb ioctl, void __user argp)
		static int uvio_copy_and_check_ioctl(struct uvio_ioctl_cb ioctl, void __user argp,
		unsigned long cmd)
		{
		u8 nr = _IOC_NR(cmd);

		if (_IOC_DIR(cmd) != (_IOC_READ \| _IOC_WRITE))
		return -ENOIOCTLCMD;
		if (_IOC_TYPE(cmd) != UVIO_TYPE_UVC)
		return -ENOIOCTLCMD;
		if (nr >= UVIO_IOCTL_NUM_IOCTLS)
		return -ENOIOCTLCMD;
		if (_IOC_SIZE(cmd) != sizeof(*ioctl))
		return -ENOIOCTLCMD;
		if (copy_from_user(ioctl, argp, sizeof(*ioctl)))
		return -EFAULT;
		if (ioctl->flags != 0)
		@@ -194,7 +251,7 @@ static int uvio_copy_and_check_ioctl(struct uvio_ioctl_cb ioctl, void __user a
		if (memchr_inv(ioctl->reserved14, 0, sizeof(ioctl->reserved14)))
		return -EINVAL;

		return 0;
		return nr;
		}

		/*
		@@ -205,12 +262,17 @@ static long uvio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
		void __user argp = (void __user )arg;
		struct uvio_ioctl_cb uv_ioctl = { };
		long ret;
		int nr;

		switch (cmd) {
		case UVIO_IOCTL_ATT:
		ret = uvio_copy_and_check_ioctl(&uv_ioctl, argp);
		if (ret)
		return ret;
		nr = uvio_copy_and_check_ioctl(&uv_ioctl, argp, cmd);
		if (nr < 0)
		return nr;

		switch (nr) {
		case UVIO_IOCTL_UVDEV_INFO_NR:
		ret = uvio_uvdev_info(&uv_ioctl);
		break;
		case UVIO_IOCTL_ATT_NR:
		ret = uvio_attestation(&uv_ioctl);
		break;
		default:
		@@ -245,6 +307,7 @@ static void __exit uvio_dev_exit(void)

		static int __init uvio_dev_init(void)
		{
		set_supp_uv_cmds((unsigned long *)&uvdev_info.supp_uv_cmds);
		return misc_register(&uvio_dev_miscdev);
		}