1 files changed, 112 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c
new file mode 100644
index 000000000..7b739cc7a
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/svm.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Secure VM platform
+ *
+ * Copyright 2018 IBM Corporation
+ * Author: Anshuman Khandual <khandual@linux.vnet.ibm.com>
+ */
+
+#include <linux/mm.h>
+#include <linux/memblock.h>
+#include <asm/machdep.h>
+#include <asm/svm.h>
+#include <asm/swiotlb.h>
+#include <asm/ultravisor.h>
+#include <asm/dtl.h>
+
+static int __init init_svm(void)
+{
+	if (!is_secure_guest())
+		return 0;
+
+	/* Don't release the SWIOTLB buffer. */
+	ppc_swiotlb_enable = 1;
+
+	/*
+	 * Since the guest memory is inaccessible to the host, devices always
+	 * need to use the SWIOTLB buffer for DMA even if dma_capable() says
+	 * otherwise.
+	 */
+	swiotlb_force = SWIOTLB_FORCE;
+
+	/* Share the SWIOTLB buffer with the host. */
+	swiotlb_update_mem_attributes();
+
+	return 0;
+}
+machine_early_initcall(pseries, init_svm);
+
+/*
+ * Initialize SWIOTLB. Essentially the same as swiotlb_init(), except that it
+ * can allocate the buffer anywhere in memory. Since the hypervisor doesn't have
+ * any addressing limitation, we don't need to allocate it in low addresses.
+ */
+void __init svm_swiotlb_init(void)
+{
+	unsigned char *vstart;
+	unsigned long bytes, io_tlb_nslabs;
+
+	io_tlb_nslabs = (swiotlb_size_or_default() >> IO_TLB_SHIFT);
+	io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+
+	bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+
+	vstart = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE);
+	if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, false))
+		return;
+
+	if (io_tlb_start)
+		memblock_free_early(io_tlb_start,
+				    PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
+	panic("SVM: Cannot allocate SWIOTLB buffer");
+}
+
+int set_memory_encrypted(unsigned long addr, int numpages)
+{
+	if (!PAGE_ALIGNED(addr))
+		return -EINVAL;
+
+	uv_unshare_page(PHYS_PFN(__pa(addr)), numpages);
+
+	return 0;
+}
+
+int set_memory_decrypted(unsigned long addr, int numpages)
+{
+	if (!PAGE_ALIGNED(addr))
+		return -EINVAL;
+
+	uv_share_page(PHYS_PFN(__pa(addr)), numpages);
+
+	return 0;
+}
+
+/* There's one dispatch log per CPU. */
+#define NR_DTL_PAGE (DISPATCH_LOG_BYTES * CONFIG_NR_CPUS / PAGE_SIZE)
+
+static struct page *dtl_page_store[NR_DTL_PAGE];
+static long dtl_nr_pages;
+
+static bool is_dtl_page_shared(struct page *page)
+{
+	long i;
+
+	for (i = 0; i < dtl_nr_pages; i++)
+		if (dtl_page_store[i] == page)
+			return true;
+
+	return false;
+}
+
+void dtl_cache_ctor(void *addr)
+{
+	unsigned long pfn = PHYS_PFN(__pa(addr));
+	struct page *page = pfn_to_page(pfn);
+
+	if (!is_dtl_page_shared(page)) {
+		dtl_page_store[dtl_nr_pages] = page;
+		dtl_nr_pages++;
+		WARN_ON(dtl_nr_pages >= NR_DTL_PAGE);
+		uv_share_page(pfn, 1);
+	}
+}