summaryrefslogtreecommitdiffstats
path: root/arch/m68k/coldfire/cache.c
diff options
context:
space:
mode:
authorZeng Chi <zengchi@kylinos.cn>2026-09-21 18:24:42 +0800
committerSean Christopherson <seanjc@google.com>2026-09-22 08:36:16 -0700
commit119e9db233ad0f4cbd4cfb9f9385a7bca378b37d (patch)
tree660d50d4139cb750fbde1ae3432452c20726c99d /arch/m68k/coldfire/cache.c
downloadlinux-stable-119e9db233ad0f4cbd4cfb9f9385a7bca378b37d.tar.gz
linux-stable-119e9db233ad0f4cbd4cfb9f9385a7bca378b37d.zip
KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted
Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson <seanjc@google.com> Cc: David Ballesteros <davimaba.v@proton.me> Signed-off-by: Zeng Chi <zengchi@kylinos.cn> Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/m68k/coldfire/cache.c')
-rw-r--r--arch/m68k/coldfire/cache.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/arch/m68k/coldfire/cache.c b/arch/m68k/coldfire/cache.c
new file mode 100644
index 000000000..98ee89b87
--- /dev/null
+++ b/arch/m68k/coldfire/cache.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+/***************************************************************************/
+
+/*
+ * cache.c -- general ColdFire Cache maintenance code
+ *
+ * Copyright (C) 2010, Greg Ungerer (gerg@snapgear.com)
+ */
+
+/***************************************************************************/
+
+#include <linux/kernel.h>
+#include <asm/coldfire.h>
+#include <asm/mcfsim.h>
+
+/***************************************************************************/
+#ifdef CACHE_PUSH
+/***************************************************************************/
+
+/*
+ * Use cpushl to push all dirty cache lines back to memory.
+ * Older versions of GAS don't seem to know how to generate the
+ * ColdFire cpushl instruction... Oh well, bit stuff it for now.
+ */
+
+void mcf_cache_push(void)
+{
+ __asm__ __volatile__ (
+ "clrl %%d0\n\t"
+ "1:\n\t"
+ "movel %%d0,%%a0\n\t"
+ "2:\n\t"
+ ".word 0xf468\n\t"
+ "addl %0,%%a0\n\t"
+ "cmpl %1,%%a0\n\t"
+ "blt 2b\n\t"
+ "addql #1,%%d0\n\t"
+ "cmpil %2,%%d0\n\t"
+ "bne 1b\n\t"
+ : /* No output */
+ : "i" (CACHE_LINE_SIZE),
+ "i" (DCACHE_SIZE / CACHE_WAYS),
+ "i" (CACHE_WAYS)
+ : "d0", "a0" );
+}
+
+/***************************************************************************/
+#endif /* CACHE_PUSH */
+/***************************************************************************/