Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 78 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/cacheflush.h b/arch/alpha/include/asm/cacheflush.h
new file mode 100644
index 000000000..89128489c
--- /dev/null
+++ b/arch/alpha/include/asm/cacheflush.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ALPHA_CACHEFLUSH_H
+#define _ALPHA_CACHEFLUSH_H
+
+#include <linux/mm.h>
+
+/* Caches aren't brain-dead on the Alpha. */
+#define flush_cache_all()			do { } while (0)
+#define flush_cache_mm(mm)			do { } while (0)
+#define flush_cache_dup_mm(mm)			do { } while (0)
+#define flush_cache_range(vma, start, end)	do { } while (0)
+#define flush_cache_page(vma, vmaddr, pfn)	do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
+#define flush_dcache_page(page)			do { } while (0)
+#define flush_dcache_mmap_lock(mapping)		do { } while (0)
+#define flush_dcache_mmap_unlock(mapping)	do { } while (0)
+#define flush_cache_vmap(start, end)		do { } while (0)
+#define flush_cache_vunmap(start, end)		do { } while (0)
+
+/* Note that the following two definitions are _highly_ dependent
+   on the contexts in which they are used in the kernel.  I personally
+   think it is criminal how loosely defined these macros are.  */
+
+/* We need to flush the kernel's icache after loading modules.  The
+   only other use of this macro is in load_aout_interp which is not
+   used on Alpha. 
+
+   Note that this definition should *not* be used for userspace
+   icache flushing.  While functional, it is _way_ overkill.  The
+   icache is tagged with ASNs and it suffices to allocate a new ASN
+   for the process.  */
+#ifndef CONFIG_SMP
+#define flush_icache_range(start, end)		imb()
+#else
+#define flush_icache_range(start, end)		smp_imb()
+extern void smp_imb(void);
+#endif
+
+/* We need to flush the userspace icache after setting breakpoints in
+   ptrace.
+
+   Instead of indiscriminately using imb, take advantage of the fact
+   that icache entries are tagged with the ASN and load a new mm context.  */
+/* ??? Ought to use this in arch/alpha/kernel/signal.c too.  */
+
+#ifndef CONFIG_SMP
+#include <linux/sched.h>
+
+extern void __load_new_mm_context(struct mm_struct *);
+static inline void
+flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
+			unsigned long addr, int len)
+{
+	if (vma->vm_flags & VM_EXEC) {
+		struct mm_struct *mm = vma->vm_mm;
+		if (current->active_mm == mm)
+			__load_new_mm_context(mm);
+		else
+			mm->context[smp_processor_id()] = 0;
+	}
+}
+#else
+extern void flush_icache_user_range(struct vm_area_struct *vma,
+		struct page *page, unsigned long addr, int len);
+#endif
+
+/* This is used only in __do_fault and do_swap_page.  */
+#define flush_icache_page(vma, page) \
+  flush_icache_user_range((vma), (page), 0, 0)
+
+#define copy_to_user_page(vma, page, vaddr, dst, src, len) \
+do { memcpy(dst, src, len); \
+     flush_icache_user_range(vma, page, vaddr, len); \
+} while (0)
+#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
+	memcpy(dst, src, len)
+
+#endif /* _ALPHA_CACHEFLUSH_H */