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authorLinus Torvalds <torvalds@linux-foundation.org>2011-07-25 21:00:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-07-25 21:00:19 -0700
commit45b583b10a8b438b970e95a7d1d4db22c9e35004 (patch)
tree14fa481598289df0459580c582b48a9d95db51f6 /arch/um/sys-x86_64/vdso/vma.c
parent154dd78d30b56ffb8b447f629bfcceb14150e5c4 (diff)
parentf19da2ce8ef5e49b8b8ea199c3601dd45d71b262 (diff)
Merge 'akpm' patch series
* Merge akpm patch series: (122 commits) drivers/connector/cn_proc.c: remove unused local Documentation/SubmitChecklist: add RCU debug config options reiserfs: use hweight_long() reiserfs: use proper little-endian bitops pnpacpi: register disabled resources drivers/rtc/rtc-tegra.c: properly initialize spinlock drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in twl_rtc_set_time() drivers/rtc: add support for Qualcomm PMIC8xxx RTC drivers/rtc/rtc-s3c.c: support clock gating drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200 init: skip calibration delay if previously done misc/eeprom: add eeprom access driver for digsy_mtc board misc/eeprom: add driver for microwire 93xx46 EEPROMs checkpatch.pl: update $logFunctions checkpatch: make utf-8 test --strict checkpatch.pl: add ability to ignore various messages checkpatch: add a "prefer __aligned" check checkpatch: validate signature styles and To: and Cc: lines checkpatch: add __rcu as a sparse modifier checkpatch: suggest using min_t or max_t ... Did this as a merge because of (trivial) conflicts in - Documentation/feature-removal-schedule.txt - arch/xtensa/include/asm/uaccess.h that were just easier to fix up in the merge than in the patch series.
Diffstat (limited to 'arch/um/sys-x86_64/vdso/vma.c')
-rw-r--r--arch/um/sys-x86_64/vdso/vma.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/arch/um/sys-x86_64/vdso/vma.c b/arch/um/sys-x86_64/vdso/vma.c
new file mode 100644
index 00000000000..9495c8d0ce3
--- /dev/null
+++ b/arch/um/sys-x86_64/vdso/vma.c
@@ -0,0 +1,74 @@
+/*
+ * 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/slab.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <asm/page.h>
+#include <linux/init.h>
+
+unsigned int __read_mostly vdso_enabled = 1;
+unsigned long um_vdso_addr;
+
+extern unsigned long task_size;
+extern char vdso_start[], vdso_end[];
+
+static struct page **vdsop;
+
+static int __init init_vdso(void)
+{
+ struct page *um_vdso;
+
+ BUG_ON(vdso_end - vdso_start > PAGE_SIZE);
+
+ um_vdso_addr = task_size - PAGE_SIZE;
+
+ vdsop = kmalloc(GFP_KERNEL, sizeof(struct page *));
+ if (!vdsop)
+ goto oom;
+
+ um_vdso = alloc_page(GFP_KERNEL);
+ if (!um_vdso) {
+ kfree(vdsop);
+
+ goto oom;
+ }
+
+ copy_page(page_address(um_vdso), vdso_start);
+ *vdsop = um_vdso;
+
+ return 0;
+
+oom:
+ printk(KERN_ERR "Cannot allocate vdso\n");
+ vdso_enabled = 0;
+
+ return -ENOMEM;
+}
+subsys_initcall(init_vdso);
+
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+ int err;
+ struct mm_struct *mm = current->mm;
+
+ if (!vdso_enabled)
+ return 0;
+
+ down_write(&mm->mmap_sem);
+
+ err = install_special_mapping(mm, um_vdso_addr, PAGE_SIZE,
+ VM_READ|VM_EXEC|
+ VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
+ VM_ALWAYSDUMP,
+ vdsop);
+
+ up_write(&mm->mmap_sem);
+
+ return err;
+}