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authorLinus Torvalds <torvalds@linux-foundation.org>2011-11-02 09:45:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-11-02 09:45:39 -0700
commitde0a5345a55b8dd5a4695181275df0e691176830 (patch)
tree17530e824f7f46ce0b1757657179fb5957a6add5 /arch/x86/um/mem_32.c
parent994c0e992522c123298b4a91b72f5e67ba2d1123 (diff)
parent8535639810e578960233ad39def3ac2157b0c3ec (diff)
Merge branch 'for-linus' of git://github.com/richardweinberger/linux
* 'for-linus' of git://github.com/richardweinberger/linux: (90 commits) um: fix ubd cow size um: Fix kmalloc argument order in um/vdso/vma.c um: switch to use of drivers/Kconfig UserModeLinux-HOWTO.txt: fix a typo UserModeLinux-HOWTO.txt: remove ^H characters um: we need sys/user.h only on i386 um: merge delay_{32,64}.c um: distribute exports to where exported stuff is defined um: kill system-um.h um: generic ftrace.h will do... um: segment.h is x86-only and needed only there um: asm/pda.h is not needed anymore um: hw_irq.h can go generic as well um: switch to generic-y um: clean Kconfig up a bit um: a couple of missing dependencies... um: kill useless argument of free_chan() and free_one_chan() um: unify ptrace_user.h um: unify KSTK_... um: fix gcov build breakage ...
Diffstat (limited to 'arch/x86/um/mem_32.c')
-rw-r--r--arch/x86/um/mem_32.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/x86/um/mem_32.c b/arch/x86/um/mem_32.c
new file mode 100644
index 00000000000..639900a6fde
--- /dev/null
+++ b/arch/x86/um/mem_32.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/mm.h>
+#include <asm/page.h>
+#include <asm/mman.h>
+
+static struct vm_area_struct gate_vma;
+
+static int __init gate_vma_init(void)
+{
+ if (!FIXADDR_USER_START)
+ return 0;
+
+ gate_vma.vm_mm = NULL;
+ gate_vma.vm_start = FIXADDR_USER_START;
+ gate_vma.vm_end = FIXADDR_USER_END;
+ gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
+ gate_vma.vm_page_prot = __P101;
+
+ /*
+ * Make sure the vDSO gets into every core dump.
+ * Dumping its contents makes post-mortem fully interpretable later
+ * without matching up the same kernel and hardware config to see
+ * what PC values meant.
+ */
+ gate_vma.vm_flags |= VM_ALWAYSDUMP;
+
+ return 0;
+}
+__initcall(gate_vma_init);
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+ return FIXADDR_USER_START ? &gate_vma : NULL;
+}
+
+int in_gate_area_no_mm(unsigned long addr)
+{
+ if (!FIXADDR_USER_START)
+ return 0;
+
+ if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
+ return 1;
+
+ return 0;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+ struct vm_area_struct *vma = get_gate_vma(mm);
+
+ if (!vma)
+ return 0;
+
+ return (addr >= vma->vm_start) && (addr < vma->vm_end);
+}