virt/coco/sev-guest: Carve out the request issuing logic into a helper

This makes the code flow a lot easier to follow.

No functional changes.

  [ Tom: touchups. ]

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230307192449.24732-6-bp@alien8.de
This commit is contained in:
Borislav Petkov (AMD) 2023-03-07 09:19:19 -06:00
parent c5a338274b
commit 0fdb6cc7c8

View File

@ -318,27 +318,12 @@ static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8
return __enc_payload(snp_dev, req, payload, sz);
}
static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, int msg_ver,
u8 type, void *req_buf, size_t req_sz, void *resp_buf,
u32 resp_sz, __u64 *fw_err)
static int __handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, __u64 *fw_err)
{
unsigned long err, override_err = 0;
unsigned int override_npages = 0;
u64 seqno;
int rc;
/* Get message sequence and verify that its a non-zero */
seqno = snp_get_msg_seqno(snp_dev);
if (!seqno)
return -EIO;
memset(snp_dev->response, 0, sizeof(struct snp_guest_msg));
/* Encrypt the userspace provided payload */
rc = enc_payload(snp_dev, seqno, msg_ver, type, req_buf, req_sz);
if (rc)
return rc;
retry_request:
/*
* Call firmware to process the request. In this function the encrypted
@ -347,7 +332,6 @@ retry_request:
* prevent reuse of the IV.
*/
rc = snp_issue_guest_request(exit_code, &snp_dev->input, &err);
switch (rc) {
case -ENOSPC:
/*
@ -401,7 +385,33 @@ retry_request:
if (!rc && override_err == SNP_GUEST_REQ_INVALID_LEN)
return -EIO;
return rc;
}
static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, int msg_ver,
u8 type, void *req_buf, size_t req_sz, void *resp_buf,
u32 resp_sz, __u64 *fw_err)
{
u64 seqno;
int rc;
/* Get message sequence and verify that its a non-zero */
seqno = snp_get_msg_seqno(snp_dev);
if (!seqno)
return -EIO;
memset(snp_dev->response, 0, sizeof(struct snp_guest_msg));
/* Encrypt the userspace provided payload */
rc = enc_payload(snp_dev, seqno, msg_ver, type, req_buf, req_sz);
if (rc)
return rc;
rc = __handle_guest_request(snp_dev, exit_code, fw_err);
if (rc) {
if (rc == -EIO && *fw_err == SNP_GUEST_REQ_INVALID_LEN)
return rc;
dev_alert(snp_dev->dev,
"Detected error from ASP request. rc: %d, fw_err: %llu\n",
rc, *fw_err);