[Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[Brijesh Singh]

AMDs new Secure Encrypted Virtualization (SEV) feature allows the memory
contents of a virtual machines to be transparently encrypted with a key
unique to the guest VM. The programming and management of the encryption
keys are handled by the AMD Secure Processor (AMD-SP), which exposes the
commands for these tasks. The complete spec is available at:

http://support.amd.com/TechDocs/55766_SEV-KM%20API_Specification.pdf

Extend the AMD-SP driver to provide the following support:

 - an in-kernel APIs to communicate with a SEV firmware. The APIs can be
   used by the hypervisor to create encryption context for the SEV guests.

 - a userspace IOCTL to manage the platform certificates

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-crypto@vger.kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---

Changes since v4:
 * fixes reported by kbuild robot
 * update sev_cmd_buffer_len() to use tabular format to make it more readable


 drivers/crypto/ccp/psp-dev.c | 734 +++++++++++++++++++++++++++++++++++++++++++
 drivers/crypto/ccp/psp-dev.h |  17 +
 include/linux/psp-sev.h      | 171 ++++++++++
 include/uapi/linux/psp-sev.h | 112 +++++++
 4 files changed, 1034 insertions(+)
 create mode 100644 include/uapi/linux/psp-sev.h

diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
index 7480d4316239..2cab35874c03 100644
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -23,9 +23,20 @@
 #include <linux/hw_random.h>
 #include <linux/ccp.h>
 
+#include <uapi/linux/psp-sev.h>
+
 #include "sp-dev.h"
 #include "psp-dev.h"
 
+#define DEVICE_NAME	"sev"
+
+static unsigned int sev_poll;
+module_param(sev_poll, uint, 0444);
+MODULE_PARM_DESC(sev_poll, "Poll for sev command completion - any non-zero value");
+
+DEFINE_MUTEX(sev_cmd_mutex);
+static bool sev_fops_registered;
+
 const struct psp_vdata psp_entry = {
 	.offset = 0x10500,
 };
@@ -49,9 +60,725 @@ static struct psp_device *psp_alloc_struct(struct sp_device *sp)
 
 static irqreturn_t psp_irq_handler(int irq, void *data)
 {
+	struct psp_device *psp = data;
+	unsigned int status;
+
+	/* read the interrupt status */
+	status = ioread32(psp->io_regs + PSP_P2CMSG_INTSTS);
+
+	/* check if its command completion */
+	if (status & (1 << PSP_CMD_COMPLETE_REG)) {
+		int reg;
+
+		/* check if its SEV command completion */
+		reg = ioread32(psp->io_regs + PSP_CMDRESP);
+		if (reg & PSP_CMDRESP_RESP) {
+			psp->sev_int_rcvd = 1;
+			wake_up(&psp->sev_int_queue);
+		}
+	}
+
+	/* clear the interrupt status by writing 1 */
+	iowrite32(status, psp->io_regs + PSP_P2CMSG_INTSTS);
+
 	return IRQ_HANDLED;
 }
 
+static int sev_wait_cmd_poll(struct psp_device *psp, unsigned int timeout,
+			     unsigned int *reg)
+{
+	int wait = timeout * 10;	/* 100ms sleep => timeout * 10 */
+
+	while (--wait) {
+		msleep(100);
+
+		*reg = ioread32(psp->io_regs + PSP_CMDRESP);
+		if (*reg & PSP_CMDRESP_RESP)
+			break;
+	}
+
+	if (!wait) {
+		dev_err(psp->dev, "sev command timed out\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int sev_wait_cmd_ioc(struct psp_device *psp, unsigned int *reg)
+{
+	psp->sev_int_rcvd = 0;
+
+	wait_event(psp->sev_int_queue, psp->sev_int_rcvd);
+	*reg = ioread32(psp->io_regs + PSP_CMDRESP);
+
+	return 0;
+}
+
+static int sev_wait_cmd(struct psp_device *psp, unsigned int *reg)
+{
+	return (*reg & PSP_CMDRESP_IOC) ? sev_wait_cmd_ioc(psp, reg)
+					: sev_wait_cmd_poll(psp, 10, reg);
+}
+
+static int sev_cmd_buffer_len(int cmd)
+{
+	switch (cmd) {
+	case SEV_CMD_INIT:		return sizeof(struct sev_data_init);
+	case SEV_CMD_PLATFORM_STATUS:	return sizeof(struct sev_data_status);
+	case SEV_CMD_PEK_CSR:		return sizeof(struct sev_data_pek_csr);
+	case SEV_CMD_PEK_CERT_IMPORT:	return sizeof(struct sev_data_pek_cert_import);
+	case SEV_CMD_PDH_CERT_EXPORT:	return sizeof(struct sev_data_pdh_cert_export);
+	case SEV_CMD_LAUNCH_START:	return sizeof(struct sev_data_launch_start);
+	case SEV_CMD_LAUNCH_UPDATE_DATA:return sizeof(struct sev_data_launch_update_data);
+	case SEV_CMD_LAUNCH_UPDATE_VMSA:return sizeof(struct sev_data_launch_update_vmsa);
+	case SEV_CMD_LAUNCH_FINISH:	return sizeof(struct sev_data_launch_finish);
+	case SEV_CMD_LAUNCH_MEASURE:	return sizeof(struct sev_data_launch_measure);
+	case SEV_CMD_ACTIVATE:		return sizeof(struct sev_data_activate);
+	case SEV_CMD_DEACTIVATE:	return sizeof(struct sev_data_deactivate);
+	case SEV_CMD_DECOMMISSION:	return sizeof(struct sev_data_decommission);
+	case SEV_CMD_GUEST_STATUS:	return sizeof(struct sev_data_guest_status);
+	case SEV_CMD_DBG_DECRYPT:	return sizeof(struct sev_data_dbg);
+	case SEV_CMD_DBG_ENCRYPT:	return sizeof(struct sev_data_dbg);
+	case SEV_CMD_SEND_START:       	return sizeof(struct sev_data_send_start);
+	case SEV_CMD_SEND_UPDATE_DATA: 	return sizeof(struct sev_data_send_update_data);
+	case SEV_CMD_SEND_UPDATE_VMSA: 	return sizeof(struct sev_data_send_update_vmsa);
+	case SEV_CMD_SEND_FINISH:	return sizeof(struct sev_data_send_finish);
+	case SEV_CMD_RECEIVE_START:	return sizeof(struct sev_data_receive_start);
+	case SEV_CMD_RECEIVE_FINISH:	return sizeof(struct sev_data_receive_finish);
+	case SEV_CMD_RECEIVE_UPDATE_DATA:return sizeof(struct sev_data_receive_update_data);
+	case SEV_CMD_RECEIVE_UPDATE_VMSA:return sizeof(struct sev_data_receive_update_vmsa);
+	case SEV_CMD_LAUNCH_UPDATE_SECRET:return sizeof(struct sev_data_launch_secret);
+	default:			return 0;
+	}
+
+	return 0;
+}
+
+static int sev_handle_cmd(int cmd, void *data, int *psp_ret)
+{
+	struct sp_device *sp = sp_get_psp_master_device();
+	unsigned int phys_lsb, phys_msb;
+	struct psp_device *psp = sp->psp_data;
+	unsigned int reg, ret;
+
+	if (!psp)
+		return -ENODEV;
+
+	/* Get the physical address of the command buffer */
+	phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0;
+	phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;
+
+	dev_dbg(psp->dev, "sev command id %#x buffer 0x%08x%08x\n",
+			cmd, phys_msb, phys_lsb);
+	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
+			sev_cmd_buffer_len(cmd), false);
+
+	/* Only one command at a time... */
+	mutex_lock(&sev_cmd_mutex);
+
+	iowrite32(phys_lsb, psp->io_regs + PSP_CMDBUFF_ADDR_LO);
+	iowrite32(phys_msb, psp->io_regs + PSP_CMDBUFF_ADDR_HI);
+
+	reg = cmd;
+	reg <<= PSP_CMDRESP_CMD_SHIFT;
+	reg |= sev_poll ? 0 : PSP_CMDRESP_IOC;
+	iowrite32(reg, psp->io_regs + PSP_CMDRESP);
+
+	ret = sev_wait_cmd(psp, &reg);
+	if (ret)
+		goto unlock;
+
+	if (psp_ret)
+		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
+
+	if (reg & PSP_CMDRESP_ERR_MASK) {
+		dev_dbg(psp->dev, "sev command %#x failed (%#010x)\n",
+			cmd, reg & PSP_CMDRESP_ERR_MASK);
+		ret = -EIO;
+	}
+
+unlock:
+	mutex_unlock(&sev_cmd_mutex);
+	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
+			sev_cmd_buffer_len(cmd), false);
+	return ret;
+}
+
+static int sev_platform_get_state(int *state, int *error)
+{
+	struct sev_data_status *data;
+	int ret;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	ret = sev_handle_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
+	if (!ret)
+		*state = data->state;
+
+	kfree(data);
+	return ret;
+}
+
+static int sev_firmware_init(int *error)
+{
+	struct sev_data_init *data;
+	int rc;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	rc = sev_handle_cmd(SEV_CMD_INIT, data, error);
+
+	kfree(data);
+	return rc;
+}
+
+static inline int sev_ioctl_factory_reset(struct sev_issue_cmd *argp)
+{
+	return sev_handle_cmd(SEV_CMD_FACTORY_RESET, 0, &argp->error);
+}
+
+static int sev_ioctl_platform_status(struct sev_issue_cmd *argp)
+{
+	struct sev_user_data_status out;
+	struct sev_data_status *data;
+	int ret;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	ret = sev_handle_cmd(SEV_CMD_PLATFORM_STATUS, data, &argp->error);
+	if (ret)
+		goto e_free;
+
+	out.api_major = data->api_major;
+	out.api_minor = data->api_minor;
+	out.state = data->state;
+	out.owner = data->owner;
+	out.config = data->config;
+	out.build = data->build;
+	out.guest_count = data->guest_count;
+	if (copy_to_user((void __user *)(uintptr_t) argp->data,
+			 &out, sizeof(struct sev_user_data_status))) {
+		ret = -EFAULT;
+		goto e_free;
+	}
+
+e_free:
+	kfree(data);
+	return ret;
+}
+
+static void *copy_user_blob(u64 __user uaddr, u32 len)
+{
+	void *data;
+
+	if (!uaddr || !len)
+		return ERR_PTR(-EINVAL);
+
+	/* verify that blob length does not exceed our limit */
+	if (len > SEV_FW_BLOB_MAX_SIZE)
+		return ERR_PTR(-EINVAL);
+
+	data = kmalloc(len, GFP_KERNEL);
+	if (!data)
+		return ERR_PTR(-ENOMEM);
+
+	if (copy_from_user(data, (void __user *)(uintptr_t)uaddr, len))
+		goto e_free;
+
+	return data;
+
+e_free:
+	kfree(data);
+	return ERR_PTR(-EFAULT);
+}
+
+static int sev_ioctl_pek_csr(struct sev_issue_cmd *argp)
+{
+	struct sev_user_data_pek_csr input;
+	struct sev_data_pek_csr *data;
+	int do_shutdown = 0;
+	int ret, state;
+	void *blob;
+
+	if (copy_from_user(&input, (void __user *)(uintptr_t)argp->data,
+			   sizeof(struct sev_user_data_pek_csr)))
+		return -EFAULT;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+
+	/* copy the PEK certificate blob from userspace */
+	blob = NULL;
+	if (input.address) {
+		blob = copy_user_blob(input.address, input.length);
+		if (IS_ERR(blob)) {
+			ret = PTR_ERR(blob);
+			goto e_free;
+		}
+
+		data->address = __psp_pa(blob);
+		data->len = input.length;
+	}
+
+	ret = sev_platform_get_state(&state, &argp->error);
+	if (ret)
+		goto e_free_blob;
+
+	/*
+	 * PEK_CERT command can be issued only when we are in INIT state.
+	 * if current state is WORKING then reject it, if state is UNINIT
+	 * then transition the platform to INIT state before issuing the
+	 * command.
+	 */
+	if (state == SEV_STATE_WORKING) {
+		ret = -EBUSY;
+		goto e_free_blob;
+	} else if (state == SEV_STATE_UNINIT) {
+		ret = sev_firmware_init(&argp->error);
+		if (ret)
+			goto e_free_blob;
+		do_shutdown = 1;
+	}
+
+	ret = sev_handle_cmd(SEV_CMD_PEK_CSR, data, &argp->error);
+
+	input.length = data->len;
+
+	if (copy_to_user((void __user *)(uintptr_t)argp->data, &input,
+			 sizeof(struct sev_user_data_pek_csr)))
+		ret = -EFAULT;
+
+	/* transition the plaform into INIT state */
+	if (do_shutdown)
+		sev_handle_cmd(SEV_CMD_SHUTDOWN, 0, NULL);
+
+e_free_blob:
+	kfree(blob);
+e_free:
+	kfree(data);
+	return ret;
+}
+
+static int sev_ioctl_pdh_gen(struct sev_issue_cmd *argp)
+{
+	int ret, state, do_shutdown = 0;
+
+	/*
+	 * PDH_GEN command can be issued when platform is in INIT or WORKING
+	 * state. If we are in UNINIT state then transition into INIT state
+	 * before issuing the command.
+	 */
+	ret = sev_platform_get_state(&state, &argp->error);
+	if (ret)
+		return ret;
+
+	if (state == SEV_STATE_UNINIT) {
+		/* transition the plaform into INIT state */
+		ret = sev_firmware_init(&argp->error);
+		if (ret)
+			return ret;
+		do_shutdown = 1;
+	}
+
+	ret = sev_handle_cmd(SEV_CMD_PDH_GEN, 0, &argp->error);
+
+	if (do_shutdown)
+		sev_handle_cmd(SEV_CMD_SHUTDOWN, 0, NULL);
+
+	return ret;
+}
+
+static int sev_ioctl_pek_gen(struct sev_issue_cmd *argp)
+{
+	int do_shutdown = 0;
+	int ret, state;
+
+	/*
+	 * PEK_GEN command can be issued only when firmware is in INIT state.
+	 * If firmware is in UNINIT state then we transition it into INIT state
+	 * and issue the command.
+	 */
+	ret = sev_platform_get_state(&state, &argp->error);
+	if (ret)
+		return ret;
+
+	if (state == SEV_STATE_WORKING) {
+		return -EBUSY;
+	} else if (state == SEV_STATE_UNINIT) {
+		/* transition the plaform into INIT state */
+		ret = sev_firmware_init(&argp->error);
+		if (ret)
+			return ret;
+
+		do_shutdown = 1;
+	}
+
+	ret = sev_handle_cmd(SEV_CMD_PEK_GEN, 0, &argp->error);
+
+	if (do_shutdown)
+		sev_handle_cmd(SEV_CMD_SHUTDOWN, 0, NULL);
+
+	return ret;
+}
+
+static int sev_ioctl_pek_cert_import(struct sev_issue_cmd *argp)
+{
+	struct sev_user_data_pek_cert_import input;
+	struct sev_data_pek_cert_import *data;
+	int ret, state, do_shutdown = 0;
+	void *pek_blob, *oca_blob;
+
+	if (copy_from_user(&input, (void __user *)(uintptr_t) argp->data,
+			   sizeof(struct sev_user_data_pek_cert_import)))
+		return -EFAULT;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	/* copy PEK certificate blobs from userspace */
+	pek_blob = copy_user_blob(input.pek_cert_address, input.pek_cert_len);
+	if (IS_ERR(pek_blob)) {
+		ret = PTR_ERR(pek_blob);
+		goto e_free;
+	}
+
+	data->pek_cert_address = __psp_pa(pek_blob);
+	data->pek_cert_len = input.pek_cert_len;
+
+	/* copy PEK certificate blobs from userspace */
+	oca_blob = copy_user_blob(input.oca_cert_address, input.oca_cert_len);
+	if (IS_ERR(oca_blob)) {
+		ret = PTR_ERR(oca_blob);
+		goto e_free_pek;
+	}
+
+	data->oca_cert_address = __psp_pa(oca_blob);
+	data->oca_cert_len = input.oca_cert_len;
+
+	ret = sev_platform_get_state(&state, &argp->error);
+	if (ret)
+		goto e_free_oca;
+
+	/*
+	 * PEK_CERT_IMPORT command can be issued only when platform is in INIT
+	 * state. If we are in UNINIT state then transition into INIT state
+	 * before issuing the command.
+	 */
+	if (state == SEV_STATE_WORKING) {
+		ret = -EBUSY;
+		goto e_free_oca;
+	} else if (state == SEV_STATE_UNINIT) {
+		/* transition platform init INIT state */
+		ret = sev_firmware_init(&argp->error);
+		if (ret)
+			goto e_free_oca;
+		do_shutdown = 1;
+	}
+
+	ret = sev_handle_cmd(SEV_CMD_PEK_CERT_IMPORT, data, &argp->error);
+
+	if (do_shutdown)
+		sev_handle_cmd(SEV_CMD_SHUTDOWN, 0, NULL);
+
+e_free_oca:
+	kfree(oca_blob);
+e_free_pek:
+	kfree(pek_blob);
+e_free:
+	kfree(data);
+	return ret;
+}
+
+static int sev_ioctl_pdh_cert_export(struct sev_issue_cmd *argp)
+{
+	struct sev_user_data_pdh_cert_export input;
+	struct sev_data_pdh_cert_export *data;
+	int ret, state, need_shutdown = 0;
+	void *pdh_blob, *cert_blob;
+
+	if (copy_from_user(&input, (void __user *)(uintptr_t)argp->data,
+			   sizeof(struct sev_user_data_pdh_cert_export)))
+		return -EFAULT;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	pdh_blob = NULL;
+	if (input.pdh_cert_address) {
+		if (!access_ok(VERIFY_WRITE, input.pdh_cert_address,
+			       input.pdh_cert_len)) {
+			ret = -EFAULT;
+			goto e_free;
+		}
+
+		if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) {
+			ret = -EINVAL;
+			goto e_free;
+		}
+
+		pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
+		if (!pdh_blob) {
+			ret = -ENOMEM;
+			goto e_free;
+		}
+
+		data->pdh_cert_address = __psp_pa(pdh_blob);
+		data->pdh_cert_len = input.pdh_cert_len;
+	}
+
+	cert_blob = NULL;
+	if (input.cert_chain_address) {
+		if (!access_ok(VERIFY_WRITE, input.cert_chain_address,
+			       input.cert_chain_len)) {
+			ret = -EFAULT;
+			goto e_free_pdh;
+		}
+
+		if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) {
+			ret = -EINVAL;
+			goto e_free_pdh;
+		}
+
+		cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
+		if (!cert_blob) {
+			ret = -ENOMEM;
+			goto e_free_pdh;
+		}
+
+		data->cert_chain_address = __psp_pa(cert_blob);
+		data->cert_chain_len = input.cert_chain_len;
+	}
+
+	ret = sev_platform_get_state(&state, &argp->error);
+	if (ret)
+		goto e_free_cert;
+
+	/*
+	 * CERT_EXPORT command can be issued in INIT or WORKING state.
+	 * If we are in UNINIT state then transition into INIT state and
+	 * shutdown before exiting. But if platform is in WORKING state
+	 * then EXPORT the certificate but do not shutdown the platform.
+	 */
+	if (state == SEV_STATE_UNINIT) {
+		ret = sev_firmware_init(&argp->error);
+		if (ret)
+			goto e_free_cert;
+
+		need_shutdown = 1;
+	}
+
+	ret = sev_handle_cmd(SEV_CMD_PDH_CERT_EXPORT, data, &argp->error);
+
+	input.cert_chain_len = data->cert_chain_len;
+	input.pdh_cert_len = data->pdh_cert_len;
+
+	/* copy certificate length to userspace */
+	if (copy_to_user((void __user *)(uintptr_t)argp->data, &input,
+			 sizeof(struct sev_user_data_pdh_cert_export)))
+		ret = -EFAULT;
+
+	if (ret)
+		goto e_shutdown;
+
+	/* copy PDH certificate to userspace */
+	if (pdh_blob &&
+	    copy_to_user((void __user *)(uintptr_t)input.pdh_cert_address,
+			 pdh_blob, input.pdh_cert_len)) {
+		ret = -EFAULT;
+		goto e_shutdown;
+	}
+
+	/* copy certificate chain to userspace */
+	if (cert_blob &&
+	    copy_to_user((void __user *)(uintptr_t)input.cert_chain_address,
+			cert_blob, input.cert_chain_len)) {
+		ret = -EFAULT;
+		goto e_shutdown;
+	}
+
+e_shutdown:
+	if (need_shutdown)
+		sev_handle_cmd(SEV_CMD_SHUTDOWN, 0, NULL);
+e_free_cert:
+	kfree(cert_blob);
+e_free_pdh:
+	kfree(pdh_blob);
+e_free:
+	kfree(data);
+	return ret;
+}
+
+static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	struct sev_issue_cmd input;
+	int ret = -EFAULT;
+
+	if (ioctl != SEV_ISSUE_CMD)
+		return -EINVAL;
+
+	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
+		return -EFAULT;
+
+	if (input.cmd > SEV_CMD_MAX)
+		return -EINVAL;
+
+	switch (input.cmd) {
+
+	case SEV_USER_CMD_FACTORY_RESET: {
+		ret = sev_ioctl_factory_reset(&input);
+		break;
+	}
+	case SEV_USER_CMD_PLATFORM_STATUS: {
+		ret = sev_ioctl_platform_status(&input);
+		break;
+	}
+	case SEV_USER_CMD_PEK_GEN: {
+		ret = sev_ioctl_pek_gen(&input);
+		break;
+	}
+	case SEV_USER_CMD_PDH_GEN: {
+		ret = sev_ioctl_pdh_gen(&input);
+		break;
+	}
+	case SEV_USER_CMD_PEK_CSR: {
+		ret = sev_ioctl_pek_csr(&input);
+		break;
+	}
+	case SEV_USER_CMD_PEK_CERT_IMPORT: {
+		ret = sev_ioctl_pek_cert_import(&input);
+		break;
+	}
+	case SEV_USER_CMD_PDH_CERT_EXPORT: {
+		ret = sev_ioctl_pdh_cert_export(&input);
+		break;
+	}
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
+		ret = -EFAULT;
+
+	return ret;
+}
+
+
+const struct file_operations sev_fops = {
+	.owner	= THIS_MODULE,
+	.unlocked_ioctl = sev_ioctl,
+};
+
+int sev_platform_init(struct sev_data_init *data, int *error)
+{
+	return sev_handle_cmd(SEV_CMD_INIT, data, error);
+}
+EXPORT_SYMBOL_GPL(sev_platform_init);
+
+int sev_platform_shutdown(int *error)
+{
+	return sev_handle_cmd(SEV_CMD_SHUTDOWN, 0, error);
+}
+EXPORT_SYMBOL_GPL(sev_platform_shutdown);
+
+int sev_platform_status(struct sev_data_status *data, int *error)
+{
+	return sev_handle_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
+}
+EXPORT_SYMBOL_GPL(sev_platform_status);
+
+int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
+				void *data, int *error)
+{
+	if (!filep || filep->f_op != &sev_fops)
+		return -EBADF;
+
+	return sev_handle_cmd(cmd, data, error);
+}
+EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
+
+int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
+{
+	return sev_handle_cmd(SEV_CMD_DEACTIVATE, data, error);
+}
+EXPORT_SYMBOL_GPL(sev_guest_deactivate);
+
+int sev_guest_activate(struct sev_data_activate *data, int *error)
+{
+	return sev_handle_cmd(SEV_CMD_ACTIVATE, data, error);
+}
+EXPORT_SYMBOL_GPL(sev_guest_activate);
+
+int sev_guest_decommission(struct sev_data_decommission *data, int *error)
+{
+	return sev_handle_cmd(SEV_CMD_DECOMMISSION, data, error);
+}
+EXPORT_SYMBOL_GPL(sev_guest_decommission);
+
+int sev_guest_df_flush(int *error)
+{
+	return sev_handle_cmd(SEV_CMD_DF_FLUSH, 0, error);
+}
+EXPORT_SYMBOL_GPL(sev_guest_df_flush);
+
+static int sev_ops_init(struct psp_device *psp)
+{
+	struct miscdevice *misc = &psp->sev_misc;
+	int ret = 0;
+
+	/*
+	 * SEV feature support can be detected on the multiple devices but the
+	 * SEV FW commands must be issued on the master. During probe time we
+	 * do not know the master hence we create /dev/sev on the first device
+	 * probe. sev_handle_cmd() finds the right master device to when issuing
+	 * the command to the firmware.
+	 */
+	if (!sev_fops_registered) {
+		misc->minor = MISC_DYNAMIC_MINOR;
+		misc->name = DEVICE_NAME;
+		misc->fops = &sev_fops;
+
+		ret = misc_register(misc);
+		if (!ret) {
+			sev_fops_registered = true;
+			psp->has_sev_fops = true;
+			init_waitqueue_head(&psp->sev_int_queue);
+			dev_info(psp->dev, "registered SEV device\n");
+		}
+	}
+
+	return ret;
+}
+
+static int sev_init(struct psp_device *psp)
+{
+	/* Check if device supports SEV feature */
+	if (!(ioread32(psp->io_regs + PSP_FEATURE_REG) & 1)) {
+		dev_dbg(psp->dev, "device does not support SEV\n");
+		return 1;
+	}
+
+	return sev_ops_init(psp);
+}
+
+static void sev_exit(struct psp_device *psp)
+{
+	if (psp->has_sev_fops)
+		misc_deregister(&psp->sev_misc);
+}
+
 int psp_dev_init(struct sp_device *sp)
 {
 	struct device *dev = sp->dev;
@@ -88,11 +815,17 @@ int psp_dev_init(struct sp_device *sp)
 	if (sp->set_psp_master_device)
 		sp->set_psp_master_device(sp);
 
+	ret = sev_init(psp);
+	if (ret)
+		goto e_irq;
+
 	/* Enable interrupt */
 	iowrite32(-1, psp->io_regs + PSP_P2CMSG_INTEN);
 
 	return 0;
 
+e_irq:
+	sp_free_psp_irq(psp->sp, psp);
 e_err:
 	sp->psp_data = NULL;
 
@@ -105,5 +838,6 @@ void psp_dev_destroy(struct sp_device *sp)
 {
 	struct psp_device *psp = sp->psp_data;
 
+	sev_exit(psp);
 	sp_free_psp_irq(sp, psp);
 }
diff --git a/drivers/crypto/ccp/psp-dev.h b/drivers/crypto/ccp/psp-dev.h
index d53970ef5960..51d3cd966eed 100644
--- a/drivers/crypto/ccp/psp-dev.h
+++ b/drivers/crypto/ccp/psp-dev.h
@@ -25,9 +25,21 @@
 #include <linux/interrupt.h>
 #include <linux/irqreturn.h>
 #include <linux/dmaengine.h>
+#include <linux/psp-sev.h>
+#include <linux/miscdevice.h>
 
 #include "sp-dev.h"
 
+#define PSP_C2PMSG(_num)		((_num) << 2)
+#define PSP_CMDRESP			PSP_C2PMSG(32)
+#define PSP_CMDBUFF_ADDR_LO		PSP_C2PMSG(56)
+#define PSP_CMDBUFF_ADDR_HI             PSP_C2PMSG(57)
+#define PSP_FEATURE_REG			PSP_C2PMSG(63)
+
+#define PSP_P2CMSG(_num)		(_num << 2)
+#define PSP_CMD_COMPLETE_REG		1
+#define PSP_CMD_COMPLETE		PSP_P2CMSG(PSP_CMD_COMPLETE_REG)
+
 #define PSP_P2CMSG_INTEN		0x0110
 #define PSP_P2CMSG_INTSTS		0x0114
 
@@ -54,6 +66,11 @@ struct psp_device {
 	struct sp_device *sp;
 
 	void __iomem *io_regs;
+
+	unsigned int sev_int_rcvd;
+	wait_queue_head_t sev_int_queue;
+	bool has_sev_fops;
+	struct miscdevice sev_misc;
 };
 
 extern const struct psp_vdata psp_entry;
diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
index f01d0e3b09b8..6bc311903832 100644
--- a/include/linux/psp-sev.h
+++ b/include/linux/psp-sev.h
@@ -512,4 +512,175 @@ struct __attribute__((__packed__)) sev_data_dbg {
 	u32 len;				/* In */
 };
 
+#if defined(CONFIG_CRYPTO_DEV_SP_PSP)
+
+/**
+ * sev_platform_init - perform SEV INIT command
+ *
+ * @init: sev_data_init structure to be processed
+ * @error: SEV command return code
+ *
+ * Returns:
+ * 0 if the SEV successfully processed the command
+ * -%ENODEV    if the SEV device is not available
+ * -%ENOTSUPP  if the SEV does not support SEV
+ * -%ETIMEDOUT if the SEV command timed out
+ * -%EIO       if the SEV returned a non-zero return code
+ */
+int sev_platform_init(struct sev_data_init *init, int *error);
+
+/**
+ * sev_platform_shutdown - perform SEV SHUTDOWN command
+ *
+ * @error: SEV command return code
+ *
+ * Returns:
+ * 0 if the SEV successfully processed the command
+ * -%ENODEV    if the SEV device is not available
+ * -%ENOTSUPP  if the SEV does not support SEV
+ * -%ETIMEDOUT if the SEV command timed out
+ * -%EIO       if the SEV returned a non-zero return code
+ */
+int sev_platform_shutdown(int *error);
+
+/**
+ * sev_platform_status - perform SEV PLATFORM_STATUS command
+ *
+ * @init: sev_data_status structure to be processed
+ * @error: SEV command return code
+ *
+ * Returns:
+ * 0 if the SEV successfully processed the command
+ * -%ENODEV    if the SEV device is not available
+ * -%ENOTSUPP  if the SEV does not support SEV
+ * -%ETIMEDOUT if the SEV command timed out
+ * -%EIO       if the SEV returned a non-zero return code
+ */
+int sev_platform_status(struct sev_data_status *status, int *error);
+/**
+ * sev_issue_cmd_external_user - issue SEV command by other driver with a file handle.
+ *
+ * The function can be used by other drivers to issue a SEV command on
+ * behalf by userspace. The caller must pass a valid SEV file descriptor
+ * so that we know that caller has access to SEV device.
+ *
+ * @filep - SEV device file pointer
+ * @cmd - command to issue
+ * @data - command buffer
+ * @error: SEV command return code
+ *
+ * Returns:
+ * 0 if the SEV successfully processed the command
+ * -%ENODEV    if the SEV device is not available
+ * -%ENOTSUPP  if the SEV does not support SEV
+ * -%ETIMEDOUT if the SEV command timed out
+ * -%EIO       if the SEV returned a non-zero return code
+ * -%EINVAL    if the SEV file descriptor is not valid
+ */
+int sev_issue_cmd_external_user(struct file *filep, unsigned int id,
+				void *data, int *error);
+
+/**
+ * sev_guest_deactivate - perform SEV DEACTIVATE command
+ *
+ * @deactivate: sev_data_deactivate structure to be processed
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_deactivate(struct sev_data_deactivate *data, int *error);
+
+/**
+ * sev_guest_activate - perform SEV ACTIVATE command
+ *
+ * @activate: sev_data_activate structure to be processed
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_activate(struct sev_data_activate *data, int *error);
+
+/**
+ * sev_guest_df_flush - perform SEV DF_FLUSH command
+ *
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_df_flush(int *error);
+
+/**
+ * sev_guest_decommission - perform SEV DECOMMISSION command
+ *
+ * @decommission: sev_data_decommission structure to be processed
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_decommission(struct sev_data_decommission *data, int *error);
+
+#else	/* !CONFIG_CRYPTO_DEV_SP_PSP */
+
+static inline int sev_platform_status(struct sev_data_status *status,
+				      int *error)
+{
+	return -ENODEV;
+}
+
+static inline int sev_platform_init(struct sev_data_init *init, int *error)
+{
+	return -ENODEV;
+}
+
+static inline int sev_platform_shutdown(int *error) { return -ENODEV; }
+
+
+static inline int sev_issue_cmd_external_user(struct file *filep,
+					unsigned int id, void *data, int *error)
+{
+	return -ENODEV;
+}
+
+static inline int sev_guest_deactivate(struct sev_data_deactivate *data,
+					int *error)
+{
+	return -ENODEV;
+}
+
+static inline int sev_guest_decommission(struct sev_data_decommission *data,
+					int *error)
+{
+	return -ENODEV;
+}
+
+static inline int sev_guest_activate(struct sev_data_activate *data,
+					int *error)
+{
+	return -ENODEV;
+}
+
+static inline int sev_guest_df_flush(int *error) { return -ENODEV; }
+
+#endif	/* CONFIG_CRYPTO_DEV_SP_PSP */
+
 #endif	/* __PSP_SEV_H__ */
diff --git a/include/uapi/linux/psp-sev.h b/include/uapi/linux/psp-sev.h
new file mode 100644
index 000000000000..db22f451dbc6
--- /dev/null
+++ b/include/uapi/linux/psp-sev.h
@@ -0,0 +1,112 @@
+
+/*
+ * Userspace interface for AMD Secure Encrypted Virtualization (SEV)
+ *
+ * Copyright (C) 2016-2017 Advanced Micro Devices, Inc.
+ *
+ * Author: Brijesh Singh <brijesh.singh@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __PSP_SEV_USER_H__
+#define __PSP_SEV_USER_H__
+
+#include <linux/types.h>
+
+/**
+ * SEV platform commands
+ */
+enum {
+	SEV_USER_CMD_FACTORY_RESET = 0,
+	SEV_USER_CMD_PLATFORM_STATUS,
+	SEV_USER_CMD_PEK_GEN,
+	SEV_USER_CMD_PEK_CSR,
+	SEV_USER_CMD_PDH_GEN,
+	SEV_USER_CMD_PDH_CERT_EXPORT,
+	SEV_USER_CMD_PEK_CERT_IMPORT,
+
+	SEV_USER_CMD_MAX,
+};
+
+/**
+ * struct sev_user_data_status - PLATFORM_STATUS command parameters
+ *
+ * @major: major API version
+ * @minor: minor API version
+ * @state: platform state
+ * @owner: self-owned or externally owned
+ * @config: platform config flags
+ * @build: firmware build id for API version
+ * @guest_count: number of active guests
+ */
+struct sev_user_data_status {
+	__u8 api_major;				/* Out */
+	__u8 api_minor;				/* Out */
+	__u8 state;				/* Out */
+	__u8 owner;				/* Out */
+	__u32 config;				/* Out */
+	__u8 build;				/* Out */
+	__u32 guest_count;			/* Out */
+};
+
+/**
+ * struct sev_user_data_pek_csr - PEK_CSR command parameters
+ *
+ * @address: PEK certificate chain
+ * @length: length of certificate
+ */
+struct sev_user_data_pek_csr {
+	__u64 address;				/* In */
+	__u32 length;				/* In/Out */
+};
+
+/**
+ * struct sev_user_data_cert_import - PEK_CERT_IMPORT command parameters
+ *
+ * @pek_address: PEK certificate chain
+ * @pek_len: length of PEK certificate
+ * @oca_address: OCA certificate chain
+ * @oca_len: length of OCA certificate
+ */
+struct sev_user_data_pek_cert_import {
+	__u64 pek_cert_address;			/* In */
+	__u32 pek_cert_len;			/* In */
+	__u64 oca_cert_address;			/* In */
+	__u32 oca_cert_len;			/* In */
+};
+
+/**
+ * struct sev_user_data_pdh_cert_export - PDH_CERT_EXPORT command parameters
+ *
+ * @pdh_address: PDH certificate address
+ * @pdh_len: length of PDH certificate
+ * @cert_chain_address: PDH certificate chain
+ * @cert_chain_len: length of PDH certificate chain
+ */
+struct sev_user_data_pdh_cert_export {
+	__u64 pdh_cert_address;			/* In */
+	__u32 pdh_cert_len;			/* In/Out */
+	__u64 cert_chain_address;		/* In */
+	__u32 cert_chain_len;			/* In/Out */
+};
+
+/**
+ * struct sev_issue_cmd - SEV ioctl parameters
+ *
+ * @cmd: SEV commands to execute
+ * @opaque: pointer to the command structure
+ * @error: SEV FW return code on failure
+ */
+struct sev_issue_cmd {
+	__u32 cmd;				/* In */
+	__u64 data;				/* In */
+	__u32 error;				/* Out */
+};
+
+#define SEV_IOC_TYPE		'S'
+#define SEV_ISSUE_CMD	_IOWR(SEV_IOC_TYPE, 0x0, struct sev_issue_cmd)
+
+#endif /* __PSP_USER_SEV_H */
-- 
2.9.5

Re: [Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[P J P]

+-- On Mon, 2 Oct 2017, Brijesh Singh wrote --+
| +static int sev_cmd_buffer_len(int cmd)
| +{
| +	switch (cmd) {
| +	case SEV_CMD_INIT:		return sizeof(struct sev_data_init);
| +	case SEV_CMD_PLATFORM_STATUS:	return sizeof(struct sev_data_status);
| +	case SEV_CMD_PEK_CSR:		return sizeof(struct sev_data_pek_csr);
| +	case SEV_CMD_PEK_CERT_IMPORT:	return sizeof(struct sev_data_pek_cert_import);
| +	case SEV_CMD_PDH_CERT_EXPORT:	return sizeof(struct sev_data_pdh_cert_export);
| +	case SEV_CMD_LAUNCH_START:	return sizeof(struct sev_data_launch_start);
| +	case SEV_CMD_LAUNCH_UPDATE_DATA:return sizeof(struct sev_data_launch_update_data);
| +	case SEV_CMD_LAUNCH_UPDATE_VMSA:return sizeof(struct sev_data_launch_update_vmsa);
| +	case SEV_CMD_LAUNCH_FINISH:	return sizeof(struct sev_data_launch_finish);
| +	case SEV_CMD_LAUNCH_MEASURE:	return sizeof(struct sev_data_launch_measure);
| +	case SEV_CMD_ACTIVATE:		return sizeof(struct sev_data_activate);
| +	case SEV_CMD_DEACTIVATE:	return sizeof(struct sev_data_deactivate);
| +	case SEV_CMD_DECOMMISSION:	return sizeof(struct sev_data_decommission);
| +	case SEV_CMD_GUEST_STATUS:	return sizeof(struct sev_data_guest_status);
| +	case SEV_CMD_DBG_DECRYPT:	return sizeof(struct sev_data_dbg);
| +	case SEV_CMD_DBG_ENCRYPT:	return sizeof(struct sev_data_dbg);
| +	case SEV_CMD_SEND_START:       	return sizeof(struct sev_data_send_start);
| +	case SEV_CMD_SEND_UPDATE_DATA: 	return sizeof(struct sev_data_send_update_data);
| +	case SEV_CMD_SEND_UPDATE_VMSA: 	return sizeof(struct sev_data_send_update_vmsa);
| +	case SEV_CMD_SEND_FINISH:	return sizeof(struct sev_data_send_finish);
| +	case SEV_CMD_RECEIVE_START:	return sizeof(struct sev_data_receive_start);
| +	case SEV_CMD_RECEIVE_FINISH:	return sizeof(struct sev_data_receive_finish);
| +	case SEV_CMD_RECEIVE_UPDATE_DATA:return sizeof(struct sev_data_receive_update_data);
| +	case SEV_CMD_RECEIVE_UPDATE_VMSA:return sizeof(struct sev_data_receive_update_vmsa);
| +	case SEV_CMD_LAUNCH_UPDATE_SECRET:return sizeof(struct sev_data_launch_secret);
| +	default:			return 0;
| +	}

Each return above needs to be on its own line.

--
 - P J P
47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F

Re: [Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[Borislav Petkov]

On Wed, Oct 04, 2017 at 12:26:11PM +0530, P J P wrote:
> Each return above needs to be on its own line.

... because?

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
-- 

Re: [Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[P J P]

+-- On Wed, 4 Oct 2017, Borislav Petkov wrote --+
| On Wed, Oct 04, 2017 at 12:26:11PM +0530, P J P wrote:
| > Each return above needs to be on its own line.
|
| ... because?

It appears to cross 80 columns limit, checkpatch.pl throws warnings. Adding 
new line would be consistent with coding style.

--
 - P J P
47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F

Re: [Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[Borislav Petkov]

On Wed, Oct 04, 2017 at 03:24:36PM +0530, P J P wrote:
> It appears to cross 80 columns limit, checkpatch.pl throws warnings. Adding 
> new line would be consistent with coding style.

The 80 cols rule is not a hard one and checkpatch should not override
common sense. This is a function which maps commands to buffer lengths
and it should be obvious at a *very* quick glance what it does. And that
is best done if it is written in a tabular manner as we do such things
in other places in the kernel too.

Btw, Brijesh, please space out those statements for even better
readability:

static int sev_cmd_buffer_len(int cmd)
{
       switch (cmd) {
       case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
       case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_data_status);
       case SEV_CMD_PEK_CSR:           		return sizeof(struct sev_data_pek_csr);
       case SEV_CMD_PEK_CERT_IMPORT:   		return sizeof(struct sev_data_pek_cert_import);
       case SEV_CMD_PDH_CERT_EXPORT:   		return sizeof(struct sev_data_pdh_cert_export);
       case SEV_CMD_LAUNCH_START:      		return sizeof(struct sev_data_launch_start);
       case SEV_CMD_LAUNCH_UPDATE_DATA:		return sizeof(struct sev_data_launch_update_data);
       case SEV_CMD_LAUNCH_UPDATE_VMSA:		return sizeof(struct sev_data_launch_update_vmsa);
       case SEV_CMD_LAUNCH_FINISH:     		return sizeof(struct sev_data_launch_finish);
       case SEV_CMD_LAUNCH_MEASURE:    		return sizeof(struct sev_data_launch_measure);
       case SEV_CMD_ACTIVATE:          		return sizeof(struct sev_data_activate);
       case SEV_CMD_DEACTIVATE:        		return sizeof(struct sev_data_deactivate);
       case SEV_CMD_DECOMMISSION:      		return sizeof(struct sev_data_decommission);
       case SEV_CMD_GUEST_STATUS:      		return sizeof(struct sev_data_guest_status);
       case SEV_CMD_DBG_DECRYPT:       		return sizeof(struct sev_data_dbg);
       case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
       case SEV_CMD_SEND_START:			return sizeof(struct sev_data_send_start);
       case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
       case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
       case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
       case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
       case SEV_CMD_RECEIVE_FINISH:    		return sizeof(struct sev_data_receive_finish);
       case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
       case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
       case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
       default:                        		return 0;
       }

       return 0;
}

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
-- 

Re: [Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[P J P]

+-- On Wed, 4 Oct 2017, Borislav Petkov wrote --+
| This is a function which maps commands to buffer lengths and it should be 
| obvious at a *very* quick glance what it does. And that is best done if it 
| is written in a tabular manner as we do such things in other places in the 
| kernel too.

  Quick glance would work if it is readable. Currently it is not if one is 
viewing it in 80 cols screen/window. They do that. Writing return on the same 
line does not add specific value IMO.

Up to you; I pointed it out as 80 columns rule makes sense to me.

--
 - P J P
47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F

Re: [Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[Borislav Petkov]

On Wed, Oct 04, 2017 at 04:12:37PM +0530, P J P wrote:
>   Quick glance would work if it is readable. Currently it is not if
> one is viewing it in 80 cols screen/window. They do that. Writing
> return on the same line does not add specific value IMO.

Then you'll have to scroll to the right like you have to do for the
gazillion other places where the 80 cols rule is overridden for
readability or string grepping or other reasons.

Or you should widen your windows.

> Up to you; I pointed it out as 80 columns rule makes sense to me.

It is up to the crypto maintainer in the end.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
-- 

Re: [Part2 PATCH v4.1 07/29] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

[Christoph Hellwig]

On Wed, Oct 04, 2017 at 11:21:53AM +0200, Borislav Petkov wrote:
> On Wed, Oct 04, 2017 at 12:26:11PM +0530, P J P wrote:
> > Each return above needs to be on its own line.
> 
> ... because?

It's actually readable by humanѕ that way.