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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/mn10300/include/asm/highmem.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/mn10300/include/asm/highmem.h')
-rw-r--r--kernel/arch/mn10300/include/asm/highmem.h131
1 files changed, 131 insertions, 0 deletions
diff --git a/kernel/arch/mn10300/include/asm/highmem.h b/kernel/arch/mn10300/include/asm/highmem.h
new file mode 100644
index 000000000..1ddea5afb
--- /dev/null
+++ b/kernel/arch/mn10300/include/asm/highmem.h
@@ -0,0 +1,131 @@
+/* MN10300 Virtual kernel memory mappings for high memory
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from include/asm-i386/highmem.h
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#ifndef _ASM_HIGHMEM_H
+#define _ASM_HIGHMEM_H
+
+#ifdef __KERNEL__
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/highmem.h>
+#include <asm/kmap_types.h>
+#include <asm/pgtable.h>
+
+/* undef for production */
+#undef HIGHMEM_DEBUG
+
+/* declarations for highmem.c */
+extern unsigned long highstart_pfn, highend_pfn;
+
+extern pte_t *kmap_pte;
+extern pgprot_t kmap_prot;
+extern pte_t *pkmap_page_table;
+
+extern void __init kmap_init(void);
+
+/*
+ * Right now we initialize only a single pte table. It can be extended
+ * easily, subsequent pte tables have to be allocated in one physical
+ * chunk of RAM.
+ */
+#define PKMAP_BASE 0xfe000000UL
+#define LAST_PKMAP 1024
+#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
+#define PKMAP_NR(virt) ((virt - PKMAP_BASE) >> PAGE_SHIFT)
+#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
+
+extern unsigned long kmap_high(struct page *page);
+extern void kunmap_high(struct page *page);
+
+static inline unsigned long kmap(struct page *page)
+{
+ if (in_interrupt())
+ BUG();
+ if (page < highmem_start_page)
+ return page_address(page);
+ return kmap_high(page);
+}
+
+static inline void kunmap(struct page *page)
+{
+ if (in_interrupt())
+ BUG();
+ if (page < highmem_start_page)
+ return;
+ kunmap_high(page);
+}
+
+/*
+ * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
+ * gives a more generic (and caching) interface. But kmap_atomic can
+ * be used in IRQ contexts, so in some (very limited) cases we need
+ * it.
+ */
+static inline void *kmap_atomic(struct page *page)
+{
+ unsigned long vaddr;
+ int idx, type;
+
+ preempt_disable();
+ pagefault_disable();
+ if (page < highmem_start_page)
+ return page_address(page);
+
+ type = kmap_atomic_idx_push();
+ idx = type + KM_TYPE_NR * smp_processor_id();
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#if HIGHMEM_DEBUG
+ if (!pte_none(*(kmap_pte - idx)))
+ BUG();
+#endif
+ set_pte(kmap_pte - idx, mk_pte(page, kmap_prot));
+ local_flush_tlb_one(vaddr);
+
+ return (void *)vaddr;
+}
+
+static inline void __kunmap_atomic(unsigned long vaddr)
+{
+ int type;
+
+ if (vaddr < FIXADDR_START) { /* FIXME */
+ pagefault_enable();
+ preempt_enable();
+ return;
+ }
+
+ type = kmap_atomic_idx();
+
+#if HIGHMEM_DEBUG
+ {
+ unsigned int idx;
+ idx = type + KM_TYPE_NR * smp_processor_id();
+
+ if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx))
+ BUG();
+
+ /*
+ * force other mappings to Oops if they'll try to access
+ * this pte without first remap it
+ */
+ pte_clear(kmap_pte - idx);
+ local_flush_tlb_one(vaddr);
+ }
+#endif
+
+ kmap_atomic_idx_pop();
+ pagefault_enable();
+ preempt_enable();
+}
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_HIGHMEM_H */