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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /ANDROID_3.4.5/arch/arm/mm/mmap.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'ANDROID_3.4.5/arch/arm/mm/mmap.c')
-rw-r--r--ANDROID_3.4.5/arch/arm/mm/mmap.c322
1 files changed, 0 insertions, 322 deletions
diff --git a/ANDROID_3.4.5/arch/arm/mm/mmap.c b/ANDROID_3.4.5/arch/arm/mm/mmap.c
deleted file mode 100644
index ce8cb197..00000000
--- a/ANDROID_3.4.5/arch/arm/mm/mmap.c
+++ /dev/null
@@ -1,322 +0,0 @@
-/*
- * linux/arch/arm/mm/mmap.c
- */
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/mman.h>
-#include <linux/shm.h>
-#include <linux/sched.h>
-#include <linux/io.h>
-#include <linux/personality.h>
-#include <linux/random.h>
-#include <asm/cachetype.h>
-
-static inline unsigned long COLOUR_ALIGN_DOWN(unsigned long addr,
- unsigned long pgoff)
-{
- unsigned long base = addr & ~(SHMLBA-1);
- unsigned long off = (pgoff << PAGE_SHIFT) & (SHMLBA-1);
-
- if (base + off <= addr)
- return base + off;
-
- return base - off;
-}
-
-#define COLOUR_ALIGN(addr,pgoff) \
- ((((addr)+SHMLBA-1)&~(SHMLBA-1)) + \
- (((pgoff)<<PAGE_SHIFT) & (SHMLBA-1)))
-
-/* gap between mmap and stack */
-#define MIN_GAP (128*1024*1024UL)
-#define MAX_GAP ((TASK_SIZE)/6*5)
-
-static int mmap_is_legacy(void)
-{
- if (current->personality & ADDR_COMPAT_LAYOUT)
- return 1;
-
- if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
- return 1;
-
- return sysctl_legacy_va_layout;
-}
-
-static unsigned long mmap_base(unsigned long rnd)
-{
- unsigned long gap = rlimit(RLIMIT_STACK);
-
- if (gap < MIN_GAP)
- gap = MIN_GAP;
- else if (gap > MAX_GAP)
- gap = MAX_GAP;
-
- return PAGE_ALIGN(TASK_SIZE - gap - rnd);
-}
-
-/*
- * We need to ensure that shared mappings are correctly aligned to
- * avoid aliasing issues with VIPT caches. We need to ensure that
- * a specific page of an object is always mapped at a multiple of
- * SHMLBA bytes.
- *
- * We unconditionally provide this function for all cases, however
- * in the VIVT case, we optimise out the alignment rules.
- */
-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;
- unsigned long start_addr;
- int do_align = 0;
- int aliasing = cache_is_vipt_aliasing();
-
- /*
- * We only need to do colour alignment if either the I or D
- * caches alias.
- */
- if (aliasing)
- do_align = filp || (flags & MAP_SHARED);
-
- /*
- * We enforce the MAP_FIXED case.
- */
- if (flags & MAP_FIXED) {
- if (aliasing && flags & MAP_SHARED &&
- (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
- return -EINVAL;
- return addr;
- }
-
- if (len > TASK_SIZE)
- return -ENOMEM;
-
- if (addr) {
- if (do_align)
- addr = COLOUR_ALIGN(addr, pgoff);
- else
- addr = PAGE_ALIGN(addr);
-
- vma = find_vma(mm, addr);
- if (TASK_SIZE - len >= addr &&
- (!vma || addr + len <= vma->vm_start))
- return addr;
- }
- if (len > mm->cached_hole_size) {
- start_addr = addr = mm->free_area_cache;
- } else {
- start_addr = addr = mm->mmap_base;
- mm->cached_hole_size = 0;
- }
-
-full_search:
- if (do_align)
- addr = COLOUR_ALIGN(addr, pgoff);
- else
- addr = PAGE_ALIGN(addr);
-
- for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
- /* At this point: (!vma || addr < vma->vm_end). */
- if (TASK_SIZE - len < addr) {
- /*
- * Start a new search - just in case we missed
- * some holes.
- */
- if (start_addr != TASK_UNMAPPED_BASE) {
- start_addr = addr = TASK_UNMAPPED_BASE;
- mm->cached_hole_size = 0;
- goto full_search;
- }
- return -ENOMEM;
- }
- if (!vma || addr + len <= vma->vm_start) {
- /*
- * Remember the place where we stopped the search:
- */
- mm->free_area_cache = addr + len;
- return addr;
- }
- if (addr + mm->cached_hole_size < vma->vm_start)
- mm->cached_hole_size = vma->vm_start - addr;
- addr = vma->vm_end;
- if (do_align)
- addr = COLOUR_ALIGN(addr, pgoff);
- }
-}
-
-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_align = 0;
- int aliasing = cache_is_vipt_aliasing();
-
- /*
- * We only need to do colour alignment if either the I or D
- * caches alias.
- */
- if (aliasing)
- do_align = filp || (flags & MAP_SHARED);
-
- /* requested length too big for entire address space */
- if (len > TASK_SIZE)
- return -ENOMEM;
-
- if (flags & MAP_FIXED) {
- if (aliasing && flags & MAP_SHARED &&
- (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
- return -EINVAL;
- return addr;
- }
-
- /* requesting a specific address */
- if (addr) {
- if (do_align)
- addr = COLOUR_ALIGN(addr, pgoff);
- else
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (TASK_SIZE - len >= addr &&
- (!vma || addr + len <= vma->vm_start))
- return addr;
- }
-
- /* check if free_area_cache is useful for us */
- if (len <= mm->cached_hole_size) {
- mm->cached_hole_size = 0;
- mm->free_area_cache = mm->mmap_base;
- }
-
- /* either no address requested or can't fit in requested address hole */
- addr = mm->free_area_cache;
- if (do_align) {
- unsigned long base = COLOUR_ALIGN_DOWN(addr - len, pgoff);
- addr = base + len;
- }
-
- /* make sure it can fit in the remaining address space */
- if (addr > len) {
- vma = find_vma(mm, addr-len);
- if (!vma || addr <= vma->vm_start)
- /* remember the address as a hint for next time */
- return (mm->free_area_cache = addr-len);
- }
-
- if (mm->mmap_base < len)
- goto bottomup;
-
- addr = mm->mmap_base - len;
- if (do_align)
- addr = COLOUR_ALIGN_DOWN(addr, pgoff);
-
- do {
- /*
- * Lookup failure means no vma is above this address,
- * else if new region fits below vma->vm_start,
- * return with success:
- */
- vma = find_vma(mm, addr);
- if (!vma || addr+len <= vma->vm_start)
- /* remember the address as a hint for next time */
- return (mm->free_area_cache = addr);
-
- /* remember the largest hole we saw so far */
- if (addr + mm->cached_hole_size < vma->vm_start)
- mm->cached_hole_size = vma->vm_start - addr;
-
- /* try just below the current vma->vm_start */
- addr = vma->vm_start - len;
- if (do_align)
- addr = COLOUR_ALIGN_DOWN(addr, pgoff);
- } while (len < vma->vm_start);
-
-bottomup:
- /*
- * 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.
- */
- mm->cached_hole_size = ~0UL;
- mm->free_area_cache = TASK_UNMAPPED_BASE;
- addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
- /*
- * Restore the topdown base:
- */
- mm->free_area_cache = mm->mmap_base;
- mm->cached_hole_size = ~0UL;
-
- return addr;
-}
-
-void arch_pick_mmap_layout(struct mm_struct *mm)
-{
- unsigned long random_factor = 0UL;
-
- /* 8 bits of randomness in 20 address space bits */
- if ((current->flags & PF_RANDOMIZE) &&
- !(current->personality & ADDR_NO_RANDOMIZE))
- random_factor = (get_random_int() % (1 << 8)) << PAGE_SHIFT;
-
- if (mmap_is_legacy()) {
- mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
- mm->get_unmapped_area = arch_get_unmapped_area;
- mm->unmap_area = arch_unmap_area;
- } else {
- mm->mmap_base = mmap_base(random_factor);
- mm->get_unmapped_area = arch_get_unmapped_area_topdown;
- mm->unmap_area = arch_unmap_area_topdown;
- }
-}
-
-/*
- * You really shouldn't be using read() or write() on /dev/mem. This
- * might go away in the future.
- */
-int valid_phys_addr_range(unsigned long addr, size_t size)
-{
- if (addr < PHYS_OFFSET)
- return 0;
- if (addr + size > __pa(high_memory - 1) + 1)
- return 0;
-
- return 1;
-}
-
-/*
- * We don't use supersection mappings for mmap() on /dev/mem, which
- * means that we can't map the memory area above the 4G barrier into
- * userspace.
- */
-int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
-{
- return !(pfn + (size >> PAGE_SHIFT) > 0x00100000);
-}
-
-#ifdef CONFIG_STRICT_DEVMEM
-
-#include <linux/ioport.h>
-
-/*
- * devmem_is_allowed() checks to see if /dev/mem access to a certain
- * address is valid. The argument is a physical page number.
- * We mimic x86 here by disallowing access to system RAM as well as
- * device-exclusive MMIO regions. This effectively disable read()/write()
- * on /dev/mem.
- */
-int devmem_is_allowed(unsigned long pfn)
-{
- if (iomem_is_exclusive(pfn << PAGE_SHIFT))
- return 0;
- if (!page_is_ram(pfn))
- return 1;
- return 0;
-}
-
-#endif