ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/s390/kernel/vdso.c b/marvell/linux/arch/s390/kernel/vdso.c
new file mode 100644
index 0000000..ed1fc08
--- /dev/null
+++ b/marvell/linux/arch/s390/kernel/vdso.c
@@ -0,0 +1,310 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * vdso setup for s390
+ *
+ * Copyright IBM Corp. 2008
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/elf.h>
+#include <linux/security.h>
+#include <linux/memblock.h>
+#include <linux/compat.h>
+#include <asm/asm-offsets.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/sections.h>
+#include <asm/vdso.h>
+#include <asm/facility.h>
+
+#ifdef CONFIG_COMPAT_VDSO
+extern char vdso32_start, vdso32_end;
+static void *vdso32_kbase = &vdso32_start;
+static unsigned int vdso32_pages;
+static struct page **vdso32_pagelist;
+#endif
+
+extern char vdso64_start, vdso64_end;
+static void *vdso64_kbase = &vdso64_start;
+static unsigned int vdso64_pages;
+static struct page **vdso64_pagelist;
+
+/*
+ * Should the kernel map a VDSO page into processes and pass its
+ * address down to glibc upon exec()?
+ */
+unsigned int __read_mostly vdso_enabled = 1;
+
+static vm_fault_t vdso_fault(const struct vm_special_mapping *sm,
+ struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct page **vdso_pagelist;
+ unsigned long vdso_pages;
+
+ vdso_pagelist = vdso64_pagelist;
+ vdso_pages = vdso64_pages;
+#ifdef CONFIG_COMPAT_VDSO
+ if (vma->vm_mm->context.compat_mm) {
+ vdso_pagelist = vdso32_pagelist;
+ vdso_pages = vdso32_pages;
+ }
+#endif
+
+ if (vmf->pgoff >= vdso_pages)
+ return VM_FAULT_SIGBUS;
+
+ vmf->page = vdso_pagelist[vmf->pgoff];
+ get_page(vmf->page);
+ return 0;
+}
+
+static int vdso_mremap(const struct vm_special_mapping *sm,
+ struct vm_area_struct *vma)
+{
+ unsigned long vdso_pages;
+
+ vdso_pages = vdso64_pages;
+#ifdef CONFIG_COMPAT_VDSO
+ if (vma->vm_mm->context.compat_mm)
+ vdso_pages = vdso32_pages;
+#endif
+
+ if ((vdso_pages << PAGE_SHIFT) != vma->vm_end - vma->vm_start)
+ return -EINVAL;
+
+ if (WARN_ON_ONCE(current->mm != vma->vm_mm))
+ return -EFAULT;
+
+ current->mm->context.vdso_base = vma->vm_start;
+ return 0;
+}
+
+static const struct vm_special_mapping vdso_mapping = {
+ .name = "[vdso]",
+ .fault = vdso_fault,
+ .mremap = vdso_mremap,
+};
+
+static int __init vdso_setup(char *str)
+{
+ bool enabled;
+
+ if (!kstrtobool(str, &enabled))
+ vdso_enabled = enabled;
+ return 1;
+}
+__setup("vdso=", vdso_setup);
+
+/*
+ * The vdso data page
+ */
+static union {
+ struct vdso_data data;
+ u8 page[PAGE_SIZE];
+} vdso_data_store __page_aligned_data;
+struct vdso_data *vdso_data = &vdso_data_store.data;
+
+/*
+ * Setup vdso data page.
+ */
+static void __init vdso_init_data(struct vdso_data *vd)
+{
+ vd->ectg_available = test_facility(31);
+}
+
+/*
+ * Allocate/free per cpu vdso data.
+ */
+#define SEGMENT_ORDER 2
+
+/*
+ * The initial vdso_data structure for the boot CPU. Eventually
+ * it is replaced with a properly allocated structure in vdso_init.
+ * This is necessary because a valid S390_lowcore.vdso_per_cpu_data
+ * pointer is required to be able to return from an interrupt or
+ * program check. See the exit paths in entry.S.
+ */
+struct vdso_data boot_vdso_data __initdata;
+
+void __init vdso_alloc_boot_cpu(struct lowcore *lowcore)
+{
+ lowcore->vdso_per_cpu_data = (unsigned long) &boot_vdso_data;
+}
+
+int vdso_alloc_per_cpu(struct lowcore *lowcore)
+{
+ unsigned long segment_table, page_table, page_frame;
+ struct vdso_per_cpu_data *vd;
+
+ segment_table = __get_free_pages(GFP_KERNEL, SEGMENT_ORDER);
+ page_table = get_zeroed_page(GFP_KERNEL);
+ page_frame = get_zeroed_page(GFP_KERNEL);
+ if (!segment_table || !page_table || !page_frame)
+ goto out;
+ arch_set_page_dat(virt_to_page(segment_table), SEGMENT_ORDER);
+ arch_set_page_dat(virt_to_page(page_table), 0);
+
+ /* Initialize per-cpu vdso data page */
+ vd = (struct vdso_per_cpu_data *) page_frame;
+ vd->cpu_nr = lowcore->cpu_nr;
+ vd->node_id = cpu_to_node(vd->cpu_nr);
+
+ /* Set up page table for the vdso address space */
+ memset64((u64 *)segment_table, _SEGMENT_ENTRY_EMPTY, _CRST_ENTRIES);
+ memset64((u64 *)page_table, _PAGE_INVALID, PTRS_PER_PTE);
+
+ *(unsigned long *) segment_table = _SEGMENT_ENTRY + page_table;
+ *(unsigned long *) page_table = _PAGE_PROTECT + page_frame;
+
+ lowcore->vdso_asce = segment_table +
+ _ASCE_TABLE_LENGTH + _ASCE_USER_BITS + _ASCE_TYPE_SEGMENT;
+ lowcore->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;
+}
+
+void vdso_free_per_cpu(struct lowcore *lowcore)
+{
+ unsigned long segment_table, page_table, page_frame;
+
+ segment_table = lowcore->vdso_asce & 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);
+}
+
+/*
+ * This is called from binfmt_elf, we create the special vma for the
+ * vDSO and insert it into the mm struct tree
+ */
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ unsigned long vdso_pages;
+ unsigned long vdso_base;
+ int rc;
+
+ if (!vdso_enabled)
+ return 0;
+
+ vdso_pages = vdso64_pages;
+#ifdef CONFIG_COMPAT_VDSO
+ mm->context.compat_mm = is_compat_task();
+ if (mm->context.compat_mm)
+ vdso_pages = vdso32_pages;
+#endif
+ /*
+ * vDSO has a problem and was disabled, just don't "enable" it for
+ * the process
+ */
+ if (vdso_pages == 0)
+ return 0;
+
+ /*
+ * pick a base address for the vDSO in process space. We try to put
+ * it at vdso_base which is the "natural" base for it, but we might
+ * fail and end up putting it elsewhere.
+ */
+ if (down_write_killable(&mm->mmap_sem))
+ return -EINTR;
+ vdso_base = get_unmapped_area(NULL, 0, vdso_pages << PAGE_SHIFT, 0, 0);
+ if (IS_ERR_VALUE(vdso_base)) {
+ rc = vdso_base;
+ goto out_up;
+ }
+
+ /*
+ * our vma flags don't have VM_WRITE so by default, the process
+ * isn't allowed to write those pages.
+ * gdb can break that with ptrace interface, and thus trigger COW
+ * on those pages but it's then your responsibility to never do that
+ * on the "data" page of the vDSO or you'll stop getting kernel
+ * updates and your nice userland gettimeofday will be totally dead.
+ * It's fine to use that for setting breakpoints in the vDSO code
+ * pages though.
+ */
+ vma = _install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
+ VM_READ|VM_EXEC|
+ VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+ &vdso_mapping);
+ if (IS_ERR(vma)) {
+ rc = PTR_ERR(vma);
+ goto out_up;
+ }
+
+ current->mm->context.vdso_base = vdso_base;
+ rc = 0;
+
+out_up:
+ up_write(&mm->mmap_sem);
+ return rc;
+}
+
+static int __init vdso_init(void)
+{
+ int i;
+
+ vdso_init_data(vdso_data);
+#ifdef CONFIG_COMPAT_VDSO
+ /* Calculate the size of the 32 bit vDSO */
+ vdso32_pages = ((&vdso32_end - &vdso32_start
+ + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1;
+
+ /* Make sure pages are in the correct state */
+ vdso32_pagelist = kcalloc(vdso32_pages + 1, sizeof(struct page *),
+ GFP_KERNEL);
+ BUG_ON(vdso32_pagelist == NULL);
+ for (i = 0; i < vdso32_pages - 1; i++) {
+ struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
+ get_page(pg);
+ vdso32_pagelist[i] = pg;
+ }
+ vdso32_pagelist[vdso32_pages - 1] = virt_to_page(vdso_data);
+ vdso32_pagelist[vdso32_pages] = NULL;
+#endif
+
+ /* Calculate the size of the 64 bit vDSO */
+ vdso64_pages = ((&vdso64_end - &vdso64_start
+ + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1;
+
+ /* Make sure pages are in the correct state */
+ vdso64_pagelist = kcalloc(vdso64_pages + 1, sizeof(struct page *),
+ GFP_KERNEL);
+ BUG_ON(vdso64_pagelist == NULL);
+ for (i = 0; i < vdso64_pages - 1; i++) {
+ struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
+ get_page(pg);
+ vdso64_pagelist[i] = pg;
+ }
+ vdso64_pagelist[vdso64_pages - 1] = virt_to_page(vdso_data);
+ vdso64_pagelist[vdso64_pages] = NULL;
+ if (vdso_alloc_per_cpu(&S390_lowcore))
+ BUG();
+
+ get_page(virt_to_page(vdso_data));
+
+ return 0;
+}
+early_initcall(vdso_init);