The command can be used by the userspace to query the SNP platform status
report. See the SEV-SNP spec for more details.
Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
---
Documentation/virt/coco/sevguest.rst | 27 ++++++++++++++++++++++++
drivers/crypto/ccp/sev-dev.c | 31 ++++++++++++++++++++++++++++
drivers/crypto/ccp/sev-dev.h | 1 +
include/uapi/linux/psp-sev.h | 1 +
4 files changed, 60 insertions(+)
diff --git a/Documentation/virt/coco/sevguest.rst b/Documentation/virt/coco/sevguest.rst
index 7acb8696fca4..7c51da010039 100644
--- a/Documentation/virt/coco/sevguest.rst
+++ b/Documentation/virt/coco/sevguest.rst
@@ -52,6 +52,22 @@ to execute due to the firmware error, then fw_err code will be set.
__u64 fw_err;
};
+The host ioctl should be called to /dev/sev device. The ioctl accepts command
+id and command input structure.
+
+::
+ struct sev_issue_cmd {
+ /* Command ID */
+ __u32 cmd;
+
+ /* Command request structure */
+ __u64 data;
+
+ /* firmware error code on failure (see psp-sev.h) */
+ __u32 error;
+ };
+
+
2.1 SNP_GET_REPORT
------------------
@@ -107,3 +123,14 @@ length of the blob is lesser than expected then snp_ext_report_req.certs_len wil
be updated with the expected value.
See GHCB specification for further detail on how to parse the certificate blob.
+
+2.3 SNP_PLATFORM_STATUS
+-----------------------
+:Technology: sev-snp
+:Type: hypervisor ioctl cmd
+:Parameters (in): struct sev_data_snp_platform_status
+:Returns (out): 0 on success, -negative on error
+
+The SNP_PLATFORM_STATUS command is used to query the SNP platform status. The
+status includes API major, minor version and more. See the SEV-SNP
+specification for further details.
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 16f0d9211739..65003aba807a 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -1056,6 +1056,7 @@ static int __sev_snp_init_locked(int *error)
dev_dbg(sev->dev, "SEV-SNP firmware initialized\n");
sev_es_tmr_size = SEV_SNP_ES_TMR_SIZE;
+ sev->snp_plat_status_page = __snp_alloc_firmware_pages(GFP_KERNEL_ACCOUNT, 0, true);
return rc;
}
@@ -1083,6 +1084,9 @@ static int __sev_snp_shutdown_locked(int *error)
if (!sev->snp_inited)
return 0;
+ /* Free the status page */
+ __snp_free_firmware_pages(sev->snp_plat_status_page, 0, true);
+
/* SHUTDOWN requires the DF_FLUSH */
wbinvd_on_all_cpus();
__sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, NULL);
@@ -1345,6 +1349,30 @@ static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
return ret;
}
+static int sev_ioctl_snp_platform_status(struct sev_issue_cmd *argp)
+{
+ struct sev_device *sev = psp_master->sev_data;
+ struct sev_data_snp_platform_status_buf buf;
+ int ret;
+
+ if (!sev->snp_inited || !argp->data)
+ return -EINVAL;
+
+ if (!sev->snp_plat_status_page)
+ return -ENOMEM;
+
+ buf.status_paddr = __psp_pa(page_address(sev->snp_plat_status_page));
+ ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error);
+ if (ret)
+ return ret;
+
+ if (copy_to_user((void __user *)argp->data, page_address(sev->snp_plat_status_page),
+ sizeof(struct sev_user_data_snp_status)))
+ return -EFAULT;
+
+ return 0;
+}
+
static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
{
void __user *argp = (void __user *)arg;
@@ -1396,6 +1424,9 @@ static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
case SEV_GET_ID2:
ret = sev_ioctl_do_get_id2(&input);
break;
+ case SNP_PLATFORM_STATUS:
+ ret = sev_ioctl_snp_platform_status(&input);
+ break;
default:
ret = -EINVAL;
goto out;
diff --git a/drivers/crypto/ccp/sev-dev.h b/drivers/crypto/ccp/sev-dev.h
index fe5d7a3ebace..5efe162ad82d 100644
--- a/drivers/crypto/ccp/sev-dev.h
+++ b/drivers/crypto/ccp/sev-dev.h
@@ -66,6 +66,7 @@ struct sev_device {
bool snp_inited;
struct snp_host_map snp_host_map[MAX_SNP_HOST_MAP_BUFS];
+ struct page *snp_plat_status_page;
};
int sev_dev_init(struct psp_device *psp);
diff --git a/include/uapi/linux/psp-sev.h b/include/uapi/linux/psp-sev.h
index 226de6330a18..0c383d322097 100644
--- a/include/uapi/linux/psp-sev.h
+++ b/include/uapi/linux/psp-sev.h
@@ -28,6 +28,7 @@ enum {
SEV_PEK_CERT_IMPORT,
SEV_GET_ID, /* This command is deprecated, use SEV_GET_ID2 */
SEV_GET_ID2,
+ SNP_PLATFORM_STATUS = 256,
SEV_MAX,
};
--
2.17.1
