On Fri, Apr 30, 2021 at 07:16:07AM -0500, Brijesh Singh wrote:
> @@ -278,12 +279,28 @@ static int set_clr_page_flags(struct x86_mapping_info *info,
> if ((set | clr) & _PAGE_ENC)
> clflush_page(address);
>
> + /*
> + * If the encryption attribute is being cleared, then change the page state to
> + * shared in the RMP entry. Change of the page state must be done before the
> + * PTE updates.
> + */
> + if (clr & _PAGE_ENC)
> + snp_set_page_shared(pte_pfn(*ptep) << PAGE_SHIFT);
>From the last review:
The statement above already looks at clr - just merge the two together.
> @@ -136,6 +137,55 @@ static inline bool sev_snp_enabled(void)
> return sev_status_val & MSR_AMD64_SEV_SNP_ENABLED ? true : false;
> }
>
> +static void snp_page_state_change(unsigned long paddr, int op)
>From the last review:
no need for too many prefixes on static functions - just call this one
__change_page_state() or so, so that the below one can be called...
> +{
> + u64 val;
> +
> + if (!sev_snp_enabled())
> + return;
> +
> + /*
> + * If the page is getting changed from private to shard then invalidate the page
shared
And you can write this a lot shorter
* If private -> shared, ...
> + * before requesting the state change in the RMP table.
> + */
> + if ((op == SNP_PAGE_STATE_SHARED) && pvalidate(paddr, RMP_PG_SIZE_4K, 0))
> + goto e_pvalidate;
> +
> + /* Issue VMGEXIT to change the page state in RMP table. */
> + sev_es_wr_ghcb_msr(GHCB_MSR_PSC_REQ_GFN(paddr >> PAGE_SHIFT, op));
> + VMGEXIT();
> +
> + /* Read the response of the VMGEXIT. */
> + val = sev_es_rd_ghcb_msr();
> + if ((GHCB_RESP_CODE(val) != GHCB_MSR_PSC_RESP) || GHCB_MSR_PSC_RESP_VAL(val))
> + goto e_psc;
That label is used only once - just do the termination here directly and
remove it.
Thx.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
