v4.19.13 snapshot.
diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c
new file mode 100644
index 0000000..9220dcd
--- /dev/null
+++ b/arch/xtensa/mm/cache.c
@@ -0,0 +1,314 @@
+/*
+ * arch/xtensa/mm/cache.c
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001-2006 Tensilica Inc.
+ *
+ * Chris Zankel <chris@zankel.net>
+ * Joe Taylor
+ * Marc Gauthier
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/bootmem.h>
+#include <linux/swap.h>
+#include <linux/pagemap.h>
+
+#include <asm/bootparam.h>
+#include <asm/mmu_context.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+
+/*
+ * Note:
+ * The kernel provides one architecture bit PG_arch_1 in the page flags that
+ * can be used for cache coherency.
+ *
+ * I$-D$ coherency.
+ *
+ * The Xtensa architecture doesn't keep the instruction cache coherent with
+ * the data cache. We use the architecture bit to indicate if the caches
+ * are coherent. The kernel clears this bit whenever a page is added to the
+ * page cache. At that time, the caches might not be in sync. We, therefore,
+ * define this flag as 'clean' if set.
+ *
+ * D-cache aliasing.
+ *
+ * With cache aliasing, we have to always flush the cache when pages are
+ * unmapped (see tlb_start_vma(). So, we use this flag to indicate a dirty
+ * page.
+ *
+ *
+ *
+ */
+
+#if (DCACHE_WAY_SIZE > PAGE_SIZE)
+static inline void kmap_invalidate_coherent(struct page *page,
+ unsigned long vaddr)
+{
+ if (!DCACHE_ALIAS_EQ(page_to_phys(page), vaddr)) {
+ unsigned long kvaddr;
+
+ if (!PageHighMem(page)) {
+ kvaddr = (unsigned long)page_to_virt(page);
+
+ __invalidate_dcache_page(kvaddr);
+ } else {
+ kvaddr = TLBTEMP_BASE_1 +
+ (page_to_phys(page) & DCACHE_ALIAS_MASK);
+
+ __invalidate_dcache_page_alias(kvaddr,
+ page_to_phys(page));
+ }
+ }
+}
+
+static inline void *coherent_kvaddr(struct page *page, unsigned long base,
+ unsigned long vaddr, unsigned long *paddr)
+{
+ if (PageHighMem(page) || !DCACHE_ALIAS_EQ(page_to_phys(page), vaddr)) {
+ *paddr = page_to_phys(page);
+ return (void *)(base + (vaddr & DCACHE_ALIAS_MASK));
+ } else {
+ *paddr = 0;
+ return page_to_virt(page);
+ }
+}
+
+void clear_user_highpage(struct page *page, unsigned long vaddr)
+{
+ unsigned long paddr;
+ void *kvaddr = coherent_kvaddr(page, TLBTEMP_BASE_1, vaddr, &paddr);
+
+ preempt_disable();
+ kmap_invalidate_coherent(page, vaddr);
+ set_bit(PG_arch_1, &page->flags);
+ clear_page_alias(kvaddr, paddr);
+ preempt_enable();
+}
+EXPORT_SYMBOL(clear_user_highpage);
+
+void copy_user_highpage(struct page *dst, struct page *src,
+ unsigned long vaddr, struct vm_area_struct *vma)
+{
+ unsigned long dst_paddr, src_paddr;
+ void *dst_vaddr = coherent_kvaddr(dst, TLBTEMP_BASE_1, vaddr,
+ &dst_paddr);
+ void *src_vaddr = coherent_kvaddr(src, TLBTEMP_BASE_2, vaddr,
+ &src_paddr);
+
+ preempt_disable();
+ kmap_invalidate_coherent(dst, vaddr);
+ set_bit(PG_arch_1, &dst->flags);
+ copy_page_alias(dst_vaddr, src_vaddr, dst_paddr, src_paddr);
+ preempt_enable();
+}
+EXPORT_SYMBOL(copy_user_highpage);
+
+/*
+ * Any time the kernel writes to a user page cache page, or it is about to
+ * read from a page cache page this routine is called.
+ *
+ */
+
+void flush_dcache_page(struct page *page)
+{
+ struct address_space *mapping = page_mapping_file(page);
+
+ /*
+ * If we have a mapping but the page is not mapped to user-space
+ * yet, we simply mark this page dirty and defer flushing the
+ * caches until update_mmu().
+ */
+
+ if (mapping && !mapping_mapped(mapping)) {
+ if (!test_bit(PG_arch_1, &page->flags))
+ set_bit(PG_arch_1, &page->flags);
+ return;
+
+ } else {
+
+ unsigned long phys = page_to_phys(page);
+ unsigned long temp = page->index << PAGE_SHIFT;
+ unsigned long alias = !(DCACHE_ALIAS_EQ(temp, phys));
+ unsigned long virt;
+
+ /*
+ * Flush the page in kernel space and user space.
+ * Note that we can omit that step if aliasing is not
+ * an issue, but we do have to synchronize I$ and D$
+ * if we have a mapping.
+ */
+
+ if (!alias && !mapping)
+ return;
+
+ virt = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(virt, phys);
+
+ virt = TLBTEMP_BASE_1 + (temp & DCACHE_ALIAS_MASK);
+
+ if (alias)
+ __flush_invalidate_dcache_page_alias(virt, phys);
+
+ if (mapping)
+ __invalidate_icache_page_alias(virt, phys);
+ }
+
+ /* There shouldn't be an entry in the cache for this page anymore. */
+}
+EXPORT_SYMBOL(flush_dcache_page);
+
+/*
+ * For now, flush the whole cache. FIXME??
+ */
+
+void local_flush_cache_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ __flush_invalidate_dcache_all();
+ __invalidate_icache_all();
+}
+EXPORT_SYMBOL(local_flush_cache_range);
+
+/*
+ * Remove any entry in the cache for this page.
+ *
+ * Note that this function is only called for user pages, so use the
+ * alias versions of the cache flush functions.
+ */
+
+void local_flush_cache_page(struct vm_area_struct *vma, unsigned long address,
+ unsigned long pfn)
+{
+ /* Note that we have to use the 'alias' address to avoid multi-hit */
+
+ unsigned long phys = page_to_phys(pfn_to_page(pfn));
+ unsigned long virt = TLBTEMP_BASE_1 + (address & DCACHE_ALIAS_MASK);
+
+ __flush_invalidate_dcache_page_alias(virt, phys);
+ __invalidate_icache_page_alias(virt, phys);
+}
+EXPORT_SYMBOL(local_flush_cache_page);
+
+#endif /* DCACHE_WAY_SIZE > PAGE_SIZE */
+
+void
+update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t *ptep)
+{
+ unsigned long pfn = pte_pfn(*ptep);
+ struct page *page;
+
+ if (!pfn_valid(pfn))
+ return;
+
+ page = pfn_to_page(pfn);
+
+ /* Invalidate old entry in TLBs */
+
+ flush_tlb_page(vma, addr);
+
+#if (DCACHE_WAY_SIZE > PAGE_SIZE)
+
+ if (!PageReserved(page) && test_bit(PG_arch_1, &page->flags)) {
+ unsigned long phys = page_to_phys(page);
+ unsigned long tmp;
+
+ tmp = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(tmp, phys);
+ tmp = TLBTEMP_BASE_1 + (addr & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(tmp, phys);
+ __invalidate_icache_page_alias(tmp, phys);
+
+ clear_bit(PG_arch_1, &page->flags);
+ }
+#else
+ if (!PageReserved(page) && !test_bit(PG_arch_1, &page->flags)
+ && (vma->vm_flags & VM_EXEC) != 0) {
+ unsigned long paddr = (unsigned long)kmap_atomic(page);
+ __flush_dcache_page(paddr);
+ __invalidate_icache_page(paddr);
+ set_bit(PG_arch_1, &page->flags);
+ kunmap_atomic((void *)paddr);
+ }
+#endif
+}
+
+/*
+ * access_process_vm() has called get_user_pages(), which has done a
+ * flush_dcache_page() on the page.
+ */
+
+#if (DCACHE_WAY_SIZE > PAGE_SIZE)
+
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+ unsigned long vaddr, void *dst, const void *src,
+ unsigned long len)
+{
+ unsigned long phys = page_to_phys(page);
+ unsigned long alias = !(DCACHE_ALIAS_EQ(vaddr, phys));
+
+ /* Flush and invalidate user page if aliased. */
+
+ if (alias) {
+ unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(t, phys);
+ }
+
+ /* Copy data */
+
+ memcpy(dst, src, len);
+
+ /*
+ * Flush and invalidate kernel page if aliased and synchronize
+ * data and instruction caches for executable pages.
+ */
+
+ if (alias) {
+ unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK);
+
+ __flush_invalidate_dcache_range((unsigned long) dst, len);
+ if ((vma->vm_flags & VM_EXEC) != 0)
+ __invalidate_icache_page_alias(t, phys);
+
+ } else if ((vma->vm_flags & VM_EXEC) != 0) {
+ __flush_dcache_range((unsigned long)dst,len);
+ __invalidate_icache_range((unsigned long) dst, len);
+ }
+}
+
+extern void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
+ unsigned long vaddr, void *dst, const void *src,
+ unsigned long len)
+{
+ unsigned long phys = page_to_phys(page);
+ unsigned long alias = !(DCACHE_ALIAS_EQ(vaddr, phys));
+
+ /*
+ * Flush user page if aliased.
+ * (Note: a simply flush would be sufficient)
+ */
+
+ if (alias) {
+ unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(t, phys);
+ }
+
+ memcpy(dst, src, len);
+}
+
+#endif