WARN(1, "invalid memory op %d\n", op);
}
+static int vmgexit_psc(struct snp_psc_desc *desc)
+{
+ int cur_entry, end_entry, ret = 0;
+ struct snp_psc_desc *data;
+ struct ghcb_state state;
+ struct es_em_ctxt ctxt;
+ unsigned long flags;
+ struct ghcb *ghcb;
+
+ /*
+ * __sev_get_ghcb() needs to run with IRQs disabled because it is using
+ * a per-CPU GHCB.
+ */
+ local_irq_save(flags);
+
+ ghcb = __sev_get_ghcb(&state);
+ if (!ghcb) {
+ ret = 1;
+ goto out_unlock;
+ }
+
+ /* Copy the input desc into GHCB shared buffer */
+ data = (struct snp_psc_desc *)ghcb->shared_buffer;
+ memcpy(ghcb->shared_buffer, desc, min_t(int, GHCB_SHARED_BUF_SIZE, sizeof(*desc)));
+
+ /*
+ * As per the GHCB specification, the hypervisor can resume the guest
+ * before processing all the entries. Check whether all the entries
+ * are processed. If not, then keep retrying. Note, the hypervisor
+ * will update the data memory directly to indicate the status, so
+ * reference the data->hdr everywhere.
+ *
+ * The strategy here is to wait for the hypervisor to change the page
+ * state in the RMP table before guest accesses the memory pages. If the
+ * page state change was not successful, then later memory access will
+ * result in a crash.
+ */
+ cur_entry = data->hdr.cur_entry;
+ end_entry = data->hdr.end_entry;
+
+ while (data->hdr.cur_entry <= data->hdr.end_entry) {
+ ghcb_set_sw_scratch(ghcb, (u64)__pa(data));
+
+ /* This will advance the shared buffer data points to. */
+ ret = sev_es_ghcb_hv_call(ghcb, true, &ctxt, SVM_VMGEXIT_PSC, 0, 0);
+
+ /*
+ * Page State Change VMGEXIT can pass error code through
+ * exit_info_2.
+ */
+ if (WARN(ret || ghcb->save.sw_exit_info_2,
+ "SNP: PSC failed ret=%d exit_info_2=%llx\n",
+ ret, ghcb->save.sw_exit_info_2)) {
+ ret = 1;
+ goto out;
+ }
+
+ /* Verify that reserved bit is not set */
+ if (WARN(data->hdr.reserved, "Reserved bit is set in the PSC header\n")) {
+ ret = 1;
+ goto out;
+ }
+
+ /*
+ * Sanity check that entry processing is not going backwards.
+ * This will happen only if hypervisor is tricking us.
+ */
+ if (WARN(data->hdr.end_entry > end_entry || cur_entry > data->hdr.cur_entry,
+"SNP: PSC processing going backward, end_entry %d (got %d) cur_entry %d (got %d)\n",
+ end_entry, data->hdr.end_entry, cur_entry, data->hdr.cur_entry)) {
+ ret = 1;
+ goto out;
+ }
+ }
+
+out:
+ __sev_put_ghcb(&state);
+
+out_unlock:
+ local_irq_restore(flags);
+
+ return ret;
+}
+
+static void __set_pages_state(struct snp_psc_desc *data, unsigned long vaddr,
+ unsigned long vaddr_end, int op)
+{
+ struct psc_hdr *hdr;
+ struct psc_entry *e;
+ unsigned long pfn;
+ int i;
+
+ hdr = &data->hdr;
+ e = data->entries;
+
+ memset(data, 0, sizeof(*data));
+ i = 0;
+
+ while (vaddr < vaddr_end) {
+ if (is_vmalloc_addr((void *)vaddr))
+ pfn = vmalloc_to_pfn((void *)vaddr);
+ else
+ pfn = __pa(vaddr) >> PAGE_SHIFT;
+
+ e->gfn = pfn;
+ e->operation = op;
+ hdr->end_entry = i;
+
+ /*
+ * Current SNP implementation doesn't keep track of the RMP page
+ * size so use 4K for simplicity.
+ */
+ e->pagesize = RMP_PG_SIZE_4K;
+
+ vaddr = vaddr + PAGE_SIZE;
+ e++;
+ i++;
+ }
+
+ if (vmgexit_psc(data))
+ sev_es_terminate(SEV_TERM_SET_LINUX, GHCB_TERM_PSC);
+}
+
+static void set_pages_state(unsigned long vaddr, unsigned int npages, int op)
+{
+ unsigned long vaddr_end, next_vaddr;
+ struct snp_psc_desc *desc;
+
+ desc = kmalloc(sizeof(*desc), GFP_KERNEL_ACCOUNT);
+ if (!desc)
+ panic("SNP: failed to allocate memory for PSC descriptor\n");
+
+ vaddr = vaddr & PAGE_MASK;
+ vaddr_end = vaddr + (npages << PAGE_SHIFT);
+
+ while (vaddr < vaddr_end) {
+ /* Calculate the last vaddr that fits in one struct snp_psc_desc. */
+ next_vaddr = min_t(unsigned long, vaddr_end,
+ (VMGEXIT_PSC_MAX_ENTRY * PAGE_SIZE) + vaddr);
+
+ __set_pages_state(desc, vaddr, next_vaddr, op);
+
+ vaddr = next_vaddr;
+ }
+
+ kfree(desc);
+}
+
+void snp_set_memory_shared(unsigned long vaddr, unsigned int npages)
+{
+ if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP))
+ return;
+
+ pvalidate_pages(vaddr, npages, false);
+
+ set_pages_state(vaddr, npages, SNP_PAGE_STATE_SHARED);
+}
+
+void snp_set_memory_private(unsigned long vaddr, unsigned int npages)
+{
+ if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP))
+ return;
+
+ set_pages_state(vaddr, npages, SNP_PAGE_STATE_PRIVATE);
+
+ pvalidate_pages(vaddr, npages, true);
+}
+
int sev_es_setup_ap_jump_table(struct real_mode_header *rmh)
{
u16 startup_cs, startup_ip;
projects / linux-2.6-block.git / commitdiff