virt/coco/sev-guest: Convert the sw_exit_info_2 checking to a switch-case

commit fa4ae42cc6 upstream.

snp_issue_guest_request() checks the value returned by the hypervisor in
sw_exit_info_2 and returns a different error depending on it.

Convert those checks into a switch-case to make it more readable when
more error values are going to be checked in the future.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20230307192449.24732-8-bp@alien8.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Borislav Petkov (AMD) 2023-02-16 10:50:11 +01:00 committed by Greg Kroah-Hartman
parent 77be7df33e
commit 917f217254
1 changed files with 11 additions and 5 deletions

View File

@ -2210,15 +2210,21 @@ int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, unsigned
goto e_put;
*fw_err = ghcb->save.sw_exit_info_2;
if (ghcb->save.sw_exit_info_2) {
switch (*fw_err) {
case 0:
break;
case SNP_GUEST_REQ_INVALID_LEN:
/* Number of expected pages are returned in RBX */
if (exit_code == SVM_VMGEXIT_EXT_GUEST_REQUEST &&
ghcb->save.sw_exit_info_2 == SNP_GUEST_REQ_INVALID_LEN) {
if (exit_code == SVM_VMGEXIT_EXT_GUEST_REQUEST) {
input->data_npages = ghcb_get_rbx(ghcb);
ret = -ENOSPC;
} else {
ret = -EIO;
break;
}
fallthrough;
default:
ret = -EIO;
break;
}
e_put: