1 files changed, 65 insertions, 6 deletions

diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c
index 56cc3c4..975e997 100644
--- a/arch/mips/kernel/vdso.c
+++ b/arch/mips/kernel/vdso.c
@@ -12,9 +12,12 @@
 #include <linux/elf.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>
@@ -23,7 +26,7 @@
 static union mips_vdso_data vdso_data __page_aligned_data;
 
 /*
- * Mapping for the VDSO data pages. The real pages are mapped manually, as
+ * 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.
  */
@@ -64,25 +67,67 @@ static int __init init_vdso(void)
 }
 subsys_initcall(init_vdso);
 
+void update_vsyscall(struct timekeeper *tk)
+{
+	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;
+	}
+
+	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)
 {
 	struct mips_vdso_image *image = current->thread.abi->vdso;
 	struct mm_struct *mm = current->mm;
-	unsigned long base, vdso_addr;
+	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);
 
-	base = get_unmapped_area(NULL, 0, PAGE_SIZE + image->size, 0, 0);
+	/*
+	 * 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;
 	}
 
-	vdso_addr = base + PAGE_SIZE;
+	data_addr = base + gic_size;
+	vdso_addr = data_addr + PAGE_SIZE;
 
-	vma = _install_special_mapping(mm, base, PAGE_SIZE,
+	vma = _install_special_mapping(mm, base, vvar_size,
 				       VM_READ | VM_MAYREAD,
 				       &vdso_vvar_mapping);
 	if (IS_ERR(vma)) {
@@ -90,8 +135,22 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 		goto out;
 	}
 
+	/* 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, base,
+	ret = remap_pfn_range(vma, data_addr,
 			      virt_to_phys(&vdso_data) >> PAGE_SHIFT,
 			      PAGE_SIZE, PAGE_READONLY);
 	if (ret)