selftests/timens: Add a test for futex()

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

diff --git a/mm/mmap.c b/mm/mmap.c
index 67d11ad..d91ecb0 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -558,6 +558,50 @@ static int find_vma_links(struct mm_struct *mm, unsigned long addr,
        return 0;
 }
 
+/*
+ * vma_next() - Get the next VMA.
+ * @mm: The mm_struct.
+ * @vma: The current vma.
+ *
+ * If @vma is NULL, return the first vma in the mm.
+ *
+ * Returns: The next VMA after @vma.
+ */
+static inline struct vm_area_struct *vma_next(struct mm_struct *mm,
+                                        struct vm_area_struct *vma)
+{
+       if (!vma)
+               return mm->mmap;
+
+       return vma->vm_next;
+}
+
+/*
+ * munmap_vma_range() - munmap VMAs that overlap a range.
+ * @mm: The mm struct
+ * @start: The start of the range.
+ * @len: The length of the range.
+ * @pprev: pointer to the pointer that will be set to previous vm_area_struct
+ * @rb_link: the rb_node
+ * @rb_parent: the parent rb_node
+ *
+ * Find all the vm_area_struct that overlap from @start to
+ * @end and munmap them.  Set @pprev to the previous vm_area_struct.
+ *
+ * Returns: -ENOMEM on munmap failure or 0 on success.
+ */
+static inline int
+munmap_vma_range(struct mm_struct *mm, unsigned long start, unsigned long len,
+                struct vm_area_struct **pprev, struct rb_node ***link,
+                struct rb_node **parent, struct list_head *uf)
+{
+
+       while (find_vma_links(mm, start, start + len, pprev, link, parent))
+               if (do_munmap(mm, start, len, uf))
+                       return -ENOMEM;
+
+       return 0;
+}
 static unsigned long count_vma_pages_range(struct mm_struct *mm,
                unsigned long addr, unsigned long end)
 {
@@ -619,7 +663,7 @@ static void __vma_link_file(struct vm_area_struct *vma)
                struct address_space *mapping = file->f_mapping;
 
                if (vma->vm_flags & VM_DENYWRITE)
-                       atomic_dec(&file_inode(file)->i_writecount);
+                       put_write_access(file_inode(file));
                if (vma->vm_flags & VM_SHARED)
                        mapping_allow_writable(mapping);
 
@@ -1128,10 +1172,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
        if (vm_flags & VM_SPECIAL)
                return NULL;
 
-       if (prev)
-               next = prev->vm_next;
-       else
-               next = mm->mmap;
+       next = vma_next(mm, prev);
        area = next;
        if (area && area->vm_end == end)                /* cases 6, 7, 8 */
                next = next->vm_next;
@@ -1707,13 +1748,9 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
                        return -ENOMEM;
        }
 
-       /* Clear old maps */
-       while (find_vma_links(mm, addr, addr + len, &prev, &rb_link,
-                             &rb_parent)) {
-               if (do_munmap(mm, addr, len, uf))
-                       return -ENOMEM;
-       }
-
+       /* Clear old maps, set up prev, rb_link, rb_parent, and uf */
+       if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf))
+               return -ENOMEM;
        /*
         * Private writable mapping: check memory availability
         */
@@ -2562,7 +2599,7 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr)
        if (vma && (vma->vm_start <= addr))
                return vma;
        /* don't alter vm_end if the coredump is running */
-       if (!prev || !mmget_still_valid(mm) || expand_stack(prev, addr))
+       if (!prev || expand_stack(prev, addr))
                return NULL;
        if (prev->vm_flags & VM_LOCKED)
                populate_vma_page_range(prev, addr, prev->vm_end, NULL);
@@ -2588,9 +2625,6 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr)
                return vma;
        if (!(vma->vm_flags & VM_GROWSDOWN))
                return NULL;
-       /* don't alter vm_start if the coredump is running */
-       if (!mmget_still_valid(mm))
-               return NULL;
        start = vma->vm_start;
        if (expand_stack(vma, addr))
                return NULL;
@@ -2635,7 +2669,7 @@ static void unmap_region(struct mm_struct *mm,
                struct vm_area_struct *vma, struct vm_area_struct *prev,
                unsigned long start, unsigned long end)
 {
-       struct vm_area_struct *next = prev ? prev->vm_next : mm->mmap;
+       struct vm_area_struct *next = vma_next(mm, prev);
        struct mmu_gather tlb;
 
        lru_add_drain();
@@ -2834,7 +2868,7 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
                if (error)
                        return error;
        }
-       vma = prev ? prev->vm_next : mm->mmap;
+       vma = vma_next(mm, prev);
 
        if (unlikely(uf)) {
                /*
@@ -3052,14 +3086,9 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla
        if (error)
                return error;
 
-       /*
-        * Clear old maps.  this also does some error checking for us
-        */
-       while (find_vma_links(mm, addr, addr + len, &prev, &rb_link,
-                             &rb_parent)) {
-               if (do_munmap(mm, addr, len, uf))
-                       return -ENOMEM;
-       }
+       /* Clear old maps, set up prev, rb_link, rb_parent, and uf */
+       if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf))
+               return -ENOMEM;
 
        /* Check against address space limits *after* clearing old maps... */
        if (!may_expand_vm(mm, flags, len >> PAGE_SHIFT))