Merge tag 'tee-fix-for-v5.0' of https://git.linaro.org/people/jens.wiklander/linux...

[linux-2.6-block.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index 6c04292e16a70cd05c383c34d6cb2892d7fc6d5f..f901065c4c64cf63b455497fb993e7c4eacfc184 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2066,6 +2066,15 @@ found_highest:
        return gap_end;
 }
 
+
+#ifndef arch_get_mmap_end
+#define arch_get_mmap_end(addr)        (TASK_SIZE)
+#endif
+
+#ifndef arch_get_mmap_base
+#define arch_get_mmap_base(addr, base) (base)
+#endif
+
 /* Get an address range which is currently unmapped.
  * For shmat() with addr=0.
  *
@@ -2085,8 +2094,9 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
        struct mm_struct *mm = current->mm;
        struct vm_area_struct *vma, *prev;
        struct vm_unmapped_area_info info;
+       const unsigned long mmap_end = arch_get_mmap_end(addr);
 
-       if (len > TASK_SIZE - mmap_min_addr)
+       if (len > mmap_end - mmap_min_addr)
                return -ENOMEM;
 
        if (flags & MAP_FIXED)
@@ -2095,7 +2105,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
        if (addr) {
                addr = PAGE_ALIGN(addr);
                vma = find_vma_prev(mm, addr, &prev);
-               if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
+               if (mmap_end - len >= addr && addr >= mmap_min_addr &&
                    (!vma || addr + len <= vm_start_gap(vma)) &&
                    (!prev || addr >= vm_end_gap(prev)))
                        return addr;
@@ -2104,7 +2114,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
        info.flags = 0;
        info.length = len;
        info.low_limit = mm->mmap_base;
-       info.high_limit = TASK_SIZE;
+       info.high_limit = mmap_end;
        info.align_mask = 0;
        return vm_unmapped_area(&info);
 }
@@ -2124,9 +2134,10 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
        struct mm_struct *mm = current->mm;
        unsigned long addr = addr0;
        struct vm_unmapped_area_info info;
+       const unsigned long mmap_end = arch_get_mmap_end(addr);
 
        /* requested length too big for entire address space */
-       if (len > TASK_SIZE - mmap_min_addr)
+       if (len > mmap_end - mmap_min_addr)
                return -ENOMEM;
 
        if (flags & MAP_FIXED)
@@ -2136,7 +2147,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
        if (addr) {
                addr = PAGE_ALIGN(addr);
                vma = find_vma_prev(mm, addr, &prev);
-               if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
+               if (mmap_end - len >= addr && addr >= mmap_min_addr &&
                                (!vma || addr + len <= vm_start_gap(vma)) &&
                                (!prev || addr >= vm_end_gap(prev)))
                        return addr;
@@ -2145,7 +2156,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
        info.flags = VM_UNMAPPED_AREA_TOPDOWN;
        info.length = len;
        info.low_limit = max(PAGE_SIZE, mmap_min_addr);
-       info.high_limit = mm->mmap_base;
+       info.high_limit = arch_get_mmap_base(addr, mm->mmap_base);
        info.align_mask = 0;
        addr = vm_unmapped_area(&info);
 
@@ -2159,7 +2170,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
                VM_BUG_ON(addr != -ENOMEM);
                info.flags = 0;
                info.low_limit = TASK_UNMAPPED_BASE;
-               info.high_limit = TASK_SIZE;
+               info.high_limit = mmap_end;
                addr = vm_unmapped_area(&info);
        }
 
@@ -2962,16 +2973,6 @@ out:
        return ret;
 }
 
-static inline void verify_mm_writelocked(struct mm_struct *mm)
-{
-#ifdef CONFIG_DEBUG_VM
-       if (unlikely(down_read_trylock(&mm->mmap_sem))) {
-               WARN_ON(1);
-               up_read(&mm->mmap_sem);
-       }
-#endif
-}
-
 /*
  *  this is really a simplified "do_mmap".  it only handles
  *  anonymous maps.  eventually we may be able to do some
@@ -2998,12 +2999,6 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla
        if (error)
                return error;
 
-       /*
-        * mm->mmap_sem is required to protect against another thread
-        * changing the mappings in case we sleep.
-        */
-       verify_mm_writelocked(mm);
-
        /*
         * Clear old maps.  this also does some error checking for us
         */