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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/xtensa/include/asm/fixmap.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/xtensa/include/asm/fixmap.h')
-rw-r--r--kernel/arch/xtensa/include/asm/fixmap.h80
1 files changed, 80 insertions, 0 deletions
diff --git a/kernel/arch/xtensa/include/asm/fixmap.h b/kernel/arch/xtensa/include/asm/fixmap.h
new file mode 100644
index 000000000..62b507dee
--- /dev/null
+++ b/kernel/arch/xtensa/include/asm/fixmap.h
@@ -0,0 +1,80 @@
+/*
+ * fixmap.h: compile-time virtual memory allocation
+ *
+ * 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) 1998 Ingo Molnar
+ *
+ * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
+ */
+
+#ifndef _ASM_FIXMAP_H
+#define _ASM_FIXMAP_H
+
+#include <asm/pgtable.h>
+#ifdef CONFIG_HIGHMEM
+#include <linux/threads.h>
+#include <asm/kmap_types.h>
+#endif
+
+/*
+ * Here we define all the compile-time 'special' virtual
+ * addresses. The point is to have a constant address at
+ * compile time, but to set the physical address only
+ * in the boot process. We allocate these special addresses
+ * from the start of the consistent memory region upwards.
+ * Also this lets us do fail-safe vmalloc(), we
+ * can guarantee that these special addresses and
+ * vmalloc()-ed addresses never overlap.
+ *
+ * these 'compile-time allocated' memory buffers are
+ * fixed-size 4k pages. (or larger if used with an increment
+ * higher than 1) use fixmap_set(idx,phys) to associate
+ * physical memory with fixmap indices.
+ */
+enum fixed_addresses {
+#ifdef CONFIG_HIGHMEM
+ /* reserved pte's for temporary kernel mappings */
+ FIX_KMAP_BEGIN,
+ FIX_KMAP_END = FIX_KMAP_BEGIN +
+ (KM_TYPE_NR * NR_CPUS * DCACHE_N_COLORS) - 1,
+#endif
+ __end_of_fixed_addresses
+};
+
+#define FIXADDR_TOP (VMALLOC_START - PAGE_SIZE)
+#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
+#define FIXADDR_START ((FIXADDR_TOP - FIXADDR_SIZE) & PMD_MASK)
+
+#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT)
+
+#ifndef __ASSEMBLY__
+/*
+ * 'index to address' translation. If anyone tries to use the idx
+ * directly without translation, we catch the bug with a NULL-deference
+ * kernel oops. Illegal ranges of incoming indices are caught too.
+ */
+static __always_inline unsigned long fix_to_virt(const unsigned int idx)
+{
+ BUILD_BUG_ON(idx >= __end_of_fixed_addresses);
+ return __fix_to_virt(idx);
+}
+
+static inline unsigned long virt_to_fix(const unsigned long vaddr)
+{
+ BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
+ return __virt_to_fix(vaddr);
+}
+
+#endif
+
+#define kmap_get_fixmap_pte(vaddr) \
+ pte_offset_kernel( \
+ pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), \
+ (vaddr) \
+ )
+
+#endif