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Diffstat (limited to 'arch/s390/kernel/vdso.c')
-rw-r--r--arch/s390/kernel/vdso.c123
1 files changed, 120 insertions, 3 deletions
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index 10a6ccef4412..25a6a82f1c02 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c
@@ -31,9 +31,6 @@
#include <asm/sections.h>
#include <asm/vdso.h>
-/* Max supported size for symbol names */
-#define MAX_SYMNAME 64
-
#if defined(CONFIG_32BIT) || defined(CONFIG_COMPAT)
extern char vdso32_start, vdso32_end;
static void *vdso32_kbase = &vdso32_start;
@@ -71,6 +68,119 @@ static union {
struct vdso_data *vdso_data = &vdso_data_store.data;
/*
+ * Setup vdso data page.
+ */
+static void vdso_init_data(struct vdso_data *vd)
+{
+ unsigned int facility_list;
+
+ facility_list = stfl();
+ vd->ectg_available = switch_amode && (facility_list & 1);
+}
+
+#ifdef CONFIG_64BIT
+/*
+ * Setup per cpu vdso data page.
+ */
+static void vdso_init_per_cpu_data(int cpu, struct vdso_per_cpu_data *vpcd)
+{
+}
+
+/*
+ * Allocate/free per cpu vdso data.
+ */
+#ifdef CONFIG_64BIT
+#define SEGMENT_ORDER 2
+#else
+#define SEGMENT_ORDER 1
+#endif
+
+int vdso_alloc_per_cpu(int cpu, struct _lowcore *lowcore)
+{
+ unsigned long segment_table, page_table, page_frame;
+ u32 *psal, *aste;
+ int i;
+
+ lowcore->vdso_per_cpu_data = __LC_PASTE;
+
+ if (!switch_amode || !vdso_enabled)
+ return 0;
+
+ segment_table = __get_free_pages(GFP_KERNEL, SEGMENT_ORDER);
+ page_table = get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ page_frame = get_zeroed_page(GFP_KERNEL);
+ if (!segment_table || !page_table || !page_frame)
+ goto out;
+
+ clear_table((unsigned long *) segment_table, _SEGMENT_ENTRY_EMPTY,
+ PAGE_SIZE << SEGMENT_ORDER);
+ clear_table((unsigned long *) page_table, _PAGE_TYPE_EMPTY,
+ 256*sizeof(unsigned long));
+
+ *(unsigned long *) segment_table = _SEGMENT_ENTRY + page_table;
+ *(unsigned long *) page_table = _PAGE_RO + page_frame;
+
+ psal = (u32 *) (page_table + 256*sizeof(unsigned long));
+ aste = psal + 32;
+
+ for (i = 4; i < 32; i += 4)
+ psal[i] = 0x80000000;
+
+ lowcore->paste[4] = (u32)(addr_t) psal;
+ psal[0] = 0x20000000;
+ psal[2] = (u32)(addr_t) aste;
+ *(unsigned long *) (aste + 2) = segment_table +
+ _ASCE_TABLE_LENGTH + _ASCE_USER_BITS + _ASCE_TYPE_SEGMENT;
+ aste[4] = (u32)(addr_t) psal;
+ lowcore->vdso_per_cpu_data = page_frame;
+
+ vdso_init_per_cpu_data(cpu, (struct vdso_per_cpu_data *) page_frame);
+ return 0;
+
+out:
+ free_page(page_frame);
+ free_page(page_table);
+ free_pages(segment_table, SEGMENT_ORDER);
+ return -ENOMEM;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+void vdso_free_per_cpu(int cpu, struct _lowcore *lowcore)
+{
+ unsigned long segment_table, page_table, page_frame;
+ u32 *psal, *aste;
+
+ if (!switch_amode || !vdso_enabled)
+ return;
+
+ psal = (u32 *)(addr_t) lowcore->paste[4];
+ aste = (u32 *)(addr_t) psal[2];
+ segment_table = *(unsigned long *)(aste + 2) & PAGE_MASK;
+ page_table = *(unsigned long *) segment_table;
+ page_frame = *(unsigned long *) page_table;
+
+ free_page(page_frame);
+ free_page(page_table);
+ free_pages(segment_table, SEGMENT_ORDER);
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+static void __vdso_init_cr5(void *dummy)
+{
+ unsigned long cr5;
+
+ cr5 = offsetof(struct _lowcore, paste);
+ __ctl_load(cr5, 5, 5);
+}
+
+static void vdso_init_cr5(void)
+{
+ if (switch_amode && vdso_enabled)
+ on_each_cpu(__vdso_init_cr5, NULL, 1);
+}
+#endif /* CONFIG_64BIT */
+
+/*
* This is called from binfmt_elf, we create the special vma for the
* vDSO and insert it into the mm struct tree
*/
@@ -172,6 +282,9 @@ static int __init vdso_init(void)
{
int i;
+ if (!vdso_enabled)
+ return 0;
+ vdso_init_data(vdso_data);
#if defined(CONFIG_32BIT) || defined(CONFIG_COMPAT)
/* Calculate the size of the 32 bit vDSO */
vdso32_pages = ((&vdso32_end - &vdso32_start
@@ -208,6 +321,10 @@ static int __init vdso_init(void)
}
vdso64_pagelist[vdso64_pages - 1] = virt_to_page(vdso_data);
vdso64_pagelist[vdso64_pages] = NULL;
+#ifndef CONFIG_SMP
+ BUG_ON(vdso_alloc_per_cpu(0, S390_lowcore));
+#endif
+ vdso_init_cr5();
#endif /* CONFIG_64BIT */
get_page(virt_to_page(vdso_data));