1 files changed, 73 insertions, 7 deletions

diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index 1d3b8bc8a623..b55b35c89d6a 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -19,6 +19,7 @@
 #include <linux/pagemap.h>
 #include <linux/sched.h>
 #include <linux/sched/mm.h>
+#include <linux/syscalls.h>
 #include <asm/pdc.h>
 #include <asm/cache.h>
 #include <asm/cacheflush.h>
@@ -28,6 +29,7 @@
 #include <asm/sections.h>
 #include <asm/shmparam.h>
 #include <asm/mmu_context.h>
+#include <asm/cachectl.h>
 
 int split_tlb __ro_after_init;
 int dcache_stride __ro_after_init;
@@ -399,6 +401,7 @@ void flush_dcache_page(struct page *page)
 	unsigned long offset;
 	unsigned long addr, old_addr = 0;
 	unsigned long count = 0;
+	unsigned long flags;
 	pgoff_t pgoff;
 
 	if (mapping && !mapping_mapped(mapping)) {
@@ -420,15 +423,20 @@ void flush_dcache_page(struct page *page)
 	 * to flush one address here for them all to become coherent
 	 * on machines that support equivalent aliasing
 	 */
-	flush_dcache_mmap_lock(mapping);
+	flush_dcache_mmap_lock_irqsave(mapping, flags);
 	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
 		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
 		addr = mpnt->vm_start + offset;
 		if (parisc_requires_coherency()) {
+			bool needs_flush = false;
 			pte_t *ptep;
 
 			ptep = get_ptep(mpnt->vm_mm, addr);
-			if (ptep && pte_needs_flush(*ptep))
+			if (ptep) {
+				needs_flush = pte_needs_flush(*ptep);
+				pte_unmap(ptep);
+			}
+			if (needs_flush)
 				flush_user_cache_page(mpnt, addr);
 		} else {
 			/*
@@ -460,7 +468,7 @@ void flush_dcache_page(struct page *page)
 		}
 		WARN_ON(++count == 4096);
 	}
-	flush_dcache_mmap_unlock(mapping);
+	flush_dcache_mmap_unlock_irqrestore(mapping, flags);
 }
 EXPORT_SYMBOL(flush_dcache_page);
 
@@ -560,14 +568,20 @@ EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
 static void flush_cache_page_if_present(struct vm_area_struct *vma,
 	unsigned long vmaddr, unsigned long pfn)
 {
-	pte_t *ptep = get_ptep(vma->vm_mm, vmaddr);
+	bool needs_flush = false;
+	pte_t *ptep;
 
 	/*
 	 * The pte check is racy and sometimes the flush will trigger
 	 * a non-access TLB miss. Hopefully, the page has already been
 	 * flushed.
 	 */
-	if (ptep && pte_needs_flush(*ptep))
+	ptep = get_ptep(vma->vm_mm, vmaddr);
+	if (ptep) {
+		needs_flush = pte_needs_flush(*ptep);
+		pte_unmap(ptep);
+	}
+	if (needs_flush)
 		flush_cache_page(vma, vmaddr, pfn);
 }
 
@@ -634,17 +648,22 @@ static void flush_cache_pages(struct vm_area_struct *vma, unsigned long start, u
 	pte_t *ptep;
 
 	for (addr = start; addr < end; addr += PAGE_SIZE) {
+		bool needs_flush = false;
 		/*
 		 * The vma can contain pages that aren't present. Although
 		 * the pte search is expensive, we need the pte to find the
 		 * page pfn and to check whether the page should be flushed.
 		 */
 		ptep = get_ptep(vma->vm_mm, addr);
-		if (ptep && pte_needs_flush(*ptep)) {
+		if (ptep) {
+			needs_flush = pte_needs_flush(*ptep);
+			pfn = pte_pfn(*ptep);
+			pte_unmap(ptep);
+		}
+		if (needs_flush) {
 			if (parisc_requires_coherency()) {
 				flush_user_cache_page(vma, addr);
 			} else {
-				pfn = pte_pfn(*ptep);
 				if (WARN_ON(!pfn_valid(pfn)))
 					return;
 				__flush_cache_page(vma, addr, PFN_PHYS(pfn));
@@ -773,3 +792,50 @@ void invalidate_kernel_vmap_range(void *vaddr, int size)
 	flush_tlb_kernel_range(start, end);
 }
 EXPORT_SYMBOL(invalidate_kernel_vmap_range);
+
+
+SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
+	unsigned int, cache)
+{
+	unsigned long start, end;
+	ASM_EXCEPTIONTABLE_VAR(error);
+
+	if (bytes == 0)
+		return 0;
+	if (!access_ok((void __user *) addr, bytes))
+		return -EFAULT;
+
+	end = addr + bytes;
+
+	if (cache & DCACHE) {
+		start = addr;
+		__asm__ __volatile__ (
+#ifdef CONFIG_64BIT
+			"1: cmpb,*<<,n	%0,%2,1b\n"
+#else
+			"1: cmpb,<<,n	%0,%2,1b\n"
+#endif
+			"   fic,m	%3(%4,%0)\n"
+			"2: sync\n"
+			ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 2b)
+			: "+r" (start), "+r" (error)
+			: "r" (end), "r" (dcache_stride), "i" (SR_USER));
+	}
+
+	if (cache & ICACHE && error == 0) {
+		start = addr;
+		__asm__ __volatile__ (
+#ifdef CONFIG_64BIT
+			"1: cmpb,*<<,n	%0,%2,1b\n"
+#else
+			"1: cmpb,<<,n	%0,%2,1b\n"
+#endif
+			"   fdc,m	%3(%4,%0)\n"
+			"2: sync\n"
+			ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 2b)
+			: "+r" (start), "+r" (error)
+			: "r" (end), "r" (icache_stride), "i" (SR_USER));
+	}
+
+	return error;
+}