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-rw-r--r--arch/mips/kernel/vdso.c207
1 files changed, 130 insertions, 77 deletions
diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c
index ed2a278722a9..975e99759bab 100644
--- a/arch/mips/kernel/vdso.c
+++ b/arch/mips/kernel/vdso.c
@@ -1,122 +1,175 @@
/*
- * 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) 2015 Imagination Technologies
+ * Author: Alex Smith <alex.smith@imgtec.com>
*
- * Copyright (C) 2009, 2010 Cavium Networks, Inc.
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
*/
-
-#include <linux/kernel.h>
-#include <linux/err.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/init.h>
#include <linux/binfmts.h>
#include <linux/elf.h>
-#include <linux/vmalloc.h>
-#include <linux/unistd.h>
-#include <linux/random.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/irqchip/mips-gic.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/timekeeper_internal.h>
+#include <asm/abi.h>
#include <asm/vdso.h>
-#include <asm/uasm.h>
-#include <asm/processor.h>
+
+/* Kernel-provided data used by the VDSO. */
+static union mips_vdso_data vdso_data __page_aligned_data;
/*
- * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
+ * Mapping for the VDSO data/GIC pages. The real pages are mapped manually, as
+ * what we map and where within the area they are mapped is determined at
+ * runtime.
*/
-#define __NR_O32_sigreturn 4119
-#define __NR_O32_rt_sigreturn 4193
-#define __NR_N32_rt_sigreturn 6211
+static struct page *no_pages[] = { NULL };
+static struct vm_special_mapping vdso_vvar_mapping = {
+ .name = "[vvar]",
+ .pages = no_pages,
+};
-static struct page *vdso_page;
-
-static void __init install_trampoline(u32 *tramp, unsigned int sigreturn)
+static void __init init_vdso_image(struct mips_vdso_image *image)
{
- uasm_i_addiu(&tramp, 2, 0, sigreturn); /* li v0, sigreturn */
- uasm_i_syscall(&tramp, 0);
+ unsigned long num_pages, i;
+
+ BUG_ON(!PAGE_ALIGNED(image->data));
+ BUG_ON(!PAGE_ALIGNED(image->size));
+
+ num_pages = image->size / PAGE_SIZE;
+
+ for (i = 0; i < num_pages; i++) {
+ image->mapping.pages[i] =
+ virt_to_page(image->data + (i * PAGE_SIZE));
+ }
}
static int __init init_vdso(void)
{
- struct mips_vdso *vdso;
-
- vdso_page = alloc_page(GFP_KERNEL);
- if (!vdso_page)
- panic("Cannot allocate vdso");
-
- vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL);
- if (!vdso)
- panic("Cannot map vdso");
- clear_page(vdso);
-
- install_trampoline(vdso->rt_signal_trampoline, __NR_rt_sigreturn);
-#ifdef CONFIG_32BIT
- install_trampoline(vdso->signal_trampoline, __NR_sigreturn);
-#else
- install_trampoline(vdso->n32_rt_signal_trampoline,
- __NR_N32_rt_sigreturn);
- install_trampoline(vdso->o32_signal_trampoline, __NR_O32_sigreturn);
- install_trampoline(vdso->o32_rt_signal_trampoline,
- __NR_O32_rt_sigreturn);
+ init_vdso_image(&vdso_image);
+
+#ifdef CONFIG_MIPS32_O32
+ init_vdso_image(&vdso_image_o32);
#endif
- vunmap(vdso);
+#ifdef CONFIG_MIPS32_N32
+ init_vdso_image(&vdso_image_n32);
+#endif
return 0;
}
subsys_initcall(init_vdso);
-static unsigned long vdso_addr(unsigned long start)
+void update_vsyscall(struct timekeeper *tk)
{
- unsigned long offset = 0UL;
-
- if (current->flags & PF_RANDOMIZE) {
- offset = get_random_int();
- offset <<= PAGE_SHIFT;
- if (TASK_IS_32BIT_ADDR)
- offset &= 0xfffffful;
- else
- offset &= 0xffffffful;
+ vdso_data_write_begin(&vdso_data);
+
+ vdso_data.xtime_sec = tk->xtime_sec;
+ vdso_data.xtime_nsec = tk->tkr_mono.xtime_nsec;
+ vdso_data.wall_to_mono_sec = tk->wall_to_monotonic.tv_sec;
+ vdso_data.wall_to_mono_nsec = tk->wall_to_monotonic.tv_nsec;
+ vdso_data.cs_shift = tk->tkr_mono.shift;
+
+ vdso_data.clock_mode = tk->tkr_mono.clock->archdata.vdso_clock_mode;
+ if (vdso_data.clock_mode != VDSO_CLOCK_NONE) {
+ vdso_data.cs_mult = tk->tkr_mono.mult;
+ vdso_data.cs_cycle_last = tk->tkr_mono.cycle_last;
+ vdso_data.cs_mask = tk->tkr_mono.mask;
}
- return STACK_TOP + offset;
+ vdso_data_write_end(&vdso_data);
+}
+
+void update_vsyscall_tz(void)
+{
+ if (vdso_data.clock_mode != VDSO_CLOCK_NONE) {
+ vdso_data.tz_minuteswest = sys_tz.tz_minuteswest;
+ vdso_data.tz_dsttime = sys_tz.tz_dsttime;
+ }
}
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
- int ret;
- unsigned long addr;
+ struct mips_vdso_image *image = current->thread.abi->vdso;
struct mm_struct *mm = current->mm;
+ unsigned long gic_size, vvar_size, size, base, data_addr, vdso_addr;
+ struct vm_area_struct *vma;
+ struct resource gic_res;
+ int ret;
down_write(&mm->mmap_sem);
- addr = vdso_addr(mm->start_stack);
+ /*
+ * Determine total area size. This includes the VDSO data itself, the
+ * data page, and the GIC user page if present. Always create a mapping
+ * for the GIC user area if the GIC is present regardless of whether it
+ * is the current clocksource, in case it comes into use later on. We
+ * only map a page even though the total area is 64K, as we only need
+ * the counter registers at the start.
+ */
+ gic_size = gic_present ? PAGE_SIZE : 0;
+ vvar_size = gic_size + PAGE_SIZE;
+ size = vvar_size + image->size;
+
+ base = get_unmapped_area(NULL, 0, size, 0, 0);
+ if (IS_ERR_VALUE(base)) {
+ ret = base;
+ goto out;
+ }
+
+ data_addr = base + gic_size;
+ vdso_addr = data_addr + PAGE_SIZE;
- addr = get_unmapped_area(NULL, addr, PAGE_SIZE, 0, 0);
- if (IS_ERR_VALUE(addr)) {
- ret = addr;
- goto up_fail;
+ vma = _install_special_mapping(mm, base, vvar_size,
+ VM_READ | VM_MAYREAD,
+ &vdso_vvar_mapping);
+ if (IS_ERR(vma)) {
+ ret = PTR_ERR(vma);
+ goto out;
}
- ret = install_special_mapping(mm, addr, PAGE_SIZE,
- VM_READ|VM_EXEC|
- VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
- &vdso_page);
+ /* Map GIC user page. */
+ if (gic_size) {
+ ret = gic_get_usm_range(&gic_res);
+ if (ret)
+ goto out;
+
+ ret = io_remap_pfn_range(vma, base,
+ gic_res.start >> PAGE_SHIFT,
+ gic_size,
+ pgprot_noncached(PAGE_READONLY));
+ if (ret)
+ goto out;
+ }
+ /* Map data page. */
+ ret = remap_pfn_range(vma, data_addr,
+ virt_to_phys(&vdso_data) >> PAGE_SHIFT,
+ PAGE_SIZE, PAGE_READONLY);
if (ret)
- goto up_fail;
+ goto out;
+
+ /* Map VDSO image. */
+ vma = _install_special_mapping(mm, vdso_addr, image->size,
+ VM_READ | VM_EXEC |
+ VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
+ &image->mapping);
+ if (IS_ERR(vma)) {
+ ret = PTR_ERR(vma);
+ goto out;
+ }
- mm->context.vdso = (void *)addr;
+ mm->context.vdso = (void *)vdso_addr;
+ ret = 0;
-up_fail:
+out:
up_write(&mm->mmap_sem);
return ret;
}
-
-const char *arch_vma_name(struct vm_area_struct *vma)
-{
- if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
- return "[vdso]";
- return NULL;
-}