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-rw-r--r--arch/sh/mm/mmap.c184
1 files changed, 184 insertions, 0 deletions
diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c
new file mode 100644
index 000000000..b82199878
--- /dev/null
+++ b/arch/sh/mm/mmap.c
@@ -0,0 +1,184 @@
+/*
+ * arch/sh/mm/mmap.c
+ *
+ * Copyright (C) 2008 - 2009 Paul Mundt
+ *
+ * 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.
+ */
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/sched/mm.h>
+#include <linux/mman.h>
+#include <linux/module.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+
+unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */
+EXPORT_SYMBOL(shm_align_mask);
+
+#ifdef CONFIG_MMU
+static const pgprot_t protection_map[16] = {
+ [VM_NONE] = PAGE_NONE,
+ [VM_READ] = PAGE_READONLY,
+ [VM_WRITE] = PAGE_COPY,
+ [VM_WRITE | VM_READ] = PAGE_COPY,
+ [VM_EXEC] = PAGE_EXECREAD,
+ [VM_EXEC | VM_READ] = PAGE_EXECREAD,
+ [VM_EXEC | VM_WRITE] = PAGE_COPY,
+ [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY,
+ [VM_SHARED] = PAGE_NONE,
+ [VM_SHARED | VM_READ] = PAGE_READONLY,
+ [VM_SHARED | VM_WRITE] = PAGE_WRITEONLY,
+ [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
+ [VM_SHARED | VM_EXEC] = PAGE_EXECREAD,
+ [VM_SHARED | VM_EXEC | VM_READ] = PAGE_EXECREAD,
+ [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_RWX,
+ [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_RWX
+};
+DECLARE_VM_GET_PAGE_PROT
+
+/*
+ * To avoid cache aliases, we map the shared page with same color.
+ */
+static inline unsigned long COLOUR_ALIGN(unsigned long addr,
+ unsigned long pgoff)
+{
+ unsigned long base = (addr + shm_align_mask) & ~shm_align_mask;
+ unsigned long off = (pgoff << PAGE_SHIFT) & shm_align_mask;
+
+ return base + off;
+}
+
+unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int do_colour_align;
+ struct vm_unmapped_area_info info;
+
+ if (flags & MAP_FIXED) {
+ /* We do not accept a shared mapping if it would violate
+ * cache aliasing constraints.
+ */
+ if ((flags & MAP_SHARED) &&
+ ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
+ return -EINVAL;
+ return addr;
+ }
+
+ if (unlikely(len > TASK_SIZE))
+ return -ENOMEM;
+
+ do_colour_align = 0;
+ if (filp || (flags & MAP_SHARED))
+ do_colour_align = 1;
+
+ if (addr) {
+ if (do_colour_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ else
+ addr = PAGE_ALIGN(addr);
+
+ vma = find_vma(mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vma || addr + len <= vm_start_gap(vma)))
+ return addr;
+ }
+
+ info.flags = 0;
+ info.length = len;
+ info.low_limit = TASK_UNMAPPED_BASE;
+ info.high_limit = TASK_SIZE;
+ info.align_mask = do_colour_align ? (PAGE_MASK & shm_align_mask) : 0;
+ info.align_offset = pgoff << PAGE_SHIFT;
+ return vm_unmapped_area(&info);
+}
+
+unsigned long
+arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+ const unsigned long len, const unsigned long pgoff,
+ const unsigned long flags)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+ unsigned long addr = addr0;
+ int do_colour_align;
+ struct vm_unmapped_area_info info;
+
+ if (flags & MAP_FIXED) {
+ /* We do not accept a shared mapping if it would violate
+ * cache aliasing constraints.
+ */
+ if ((flags & MAP_SHARED) &&
+ ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
+ return -EINVAL;
+ return addr;
+ }
+
+ if (unlikely(len > TASK_SIZE))
+ return -ENOMEM;
+
+ do_colour_align = 0;
+ if (filp || (flags & MAP_SHARED))
+ do_colour_align = 1;
+
+ /* requesting a specific address */
+ if (addr) {
+ if (do_colour_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ else
+ addr = PAGE_ALIGN(addr);
+
+ vma = find_vma(mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vma || addr + len <= vm_start_gap(vma)))
+ return addr;
+ }
+
+ info.flags = VM_UNMAPPED_AREA_TOPDOWN;
+ info.length = len;
+ info.low_limit = PAGE_SIZE;
+ info.high_limit = mm->mmap_base;
+ info.align_mask = do_colour_align ? (PAGE_MASK & shm_align_mask) : 0;
+ info.align_offset = pgoff << PAGE_SHIFT;
+ addr = vm_unmapped_area(&info);
+
+ /*
+ * A failed mmap() very likely causes application failure,
+ * so fall back to the bottom-up function here. This scenario
+ * can happen with large stack limits and large mmap()
+ * allocations.
+ */
+ if (addr & ~PAGE_MASK) {
+ VM_BUG_ON(addr != -ENOMEM);
+ info.flags = 0;
+ info.low_limit = TASK_UNMAPPED_BASE;
+ info.high_limit = TASK_SIZE;
+ addr = vm_unmapped_area(&info);
+ }
+
+ return addr;
+}
+#endif /* CONFIG_MMU */
+
+/*
+ * You really shouldn't be using read() or write() on /dev/mem. This
+ * might go away in the future.
+ */
+int valid_phys_addr_range(phys_addr_t addr, size_t count)
+{
+ if (addr < __MEMORY_START)
+ return 0;
+ if (addr + count > __pa(high_memory))
+ return 0;
+
+ return 1;
+}
+
+int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
+{
+ return 1;
+}