security: remove unused sb_get_mnt_opts hook
[safe/jmp/linux-2.6] / mm / nommu.c
index 8ed0cb4..4462b6a 100644 (file)
  *  Copyright (c) 2000-2003 David McCullough <davidm@snapgear.com>
  *  Copyright (c) 2000-2001 D Jeff Dionne <jeff@uClinux.org>
  *  Copyright (c) 2002      Greg Ungerer <gerg@snapgear.com>
+ *  Copyright (c) 2007      Paul Mundt <lethal@linux-sh.org>
  */
 
+#include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/swap.h>
@@ -37,14 +39,13 @@ struct page *mem_map;
 unsigned long max_mapnr;
 unsigned long num_physpages;
 unsigned long askedalloc, realalloc;
-atomic_t vm_committed_space = ATOMIC_INIT(0);
+atomic_long_t vm_committed_space = ATOMIC_LONG_INIT(0);
 int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */
 int sysctl_overcommit_ratio = 50; /* default is 50% */
 int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
 int heap_stack_gap = 0;
 
 EXPORT_SYMBOL(mem_map);
-EXPORT_SYMBOL(__vm_enough_memory);
 EXPORT_SYMBOL(num_physpages);
 
 /* list of shareable VMAs */
@@ -104,16 +105,27 @@ unsigned int kobjsize(const void *objp)
 {
        struct page *page;
 
-       if (!objp || !((page = virt_to_page(objp))))
+       /*
+        * If the object we have should not have ksize performed on it,
+        * return size of 0
+        */
+       if (!objp || !virt_addr_valid(objp))
                return 0;
 
+       page = virt_to_head_page(objp);
+
+       /*
+        * If the allocator sets PageSlab, we know the pointer came from
+        * kmalloc().
+        */
        if (PageSlab(page))
                return ksize(objp);
 
-       BUG_ON(page->index < 0);
-       BUG_ON(page->index >= MAX_ORDER);
-
-       return (PAGE_SIZE << page->index);
+       /*
+        * The ksize() function is only guaranteed to work for pointers
+        * returned by kmalloc(). So handle arbitrary pointers here.
+        */
+       return PAGE_SIZE << compound_order(page);
 }
 
 /*
@@ -167,7 +179,7 @@ EXPORT_SYMBOL(get_user_pages);
 DEFINE_RWLOCK(vmlist_lock);
 struct vm_struct *vmlist;
 
-void vfree(void *addr)
+void vfree(const void *addr)
 {
        kfree(addr);
 }
@@ -176,19 +188,40 @@ EXPORT_SYMBOL(vfree);
 void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
 {
        /*
-        * kmalloc doesn't like __GFP_HIGHMEM for some reason
+        *  You can't specify __GFP_HIGHMEM with kmalloc() since kmalloc()
+        * returns only a logical address.
         */
        return kmalloc(size, (gfp_mask | __GFP_COMP) & ~__GFP_HIGHMEM);
 }
 EXPORT_SYMBOL(__vmalloc);
 
-struct page * vmalloc_to_page(void *addr)
+void *vmalloc_user(unsigned long size)
+{
+       void *ret;
+
+       ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
+                       PAGE_KERNEL);
+       if (ret) {
+               struct vm_area_struct *vma;
+
+               down_write(&current->mm->mmap_sem);
+               vma = find_vma(current->mm, (unsigned long)ret);
+               if (vma)
+                       vma->vm_flags |= VM_USERMAP;
+               up_write(&current->mm->mmap_sem);
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL(vmalloc_user);
+
+struct page *vmalloc_to_page(const void *addr)
 {
        return virt_to_page(addr);
 }
 EXPORT_SYMBOL(vmalloc_to_page);
 
-unsigned long vmalloc_to_pfn(void *addr)
+unsigned long vmalloc_to_pfn(const void *addr)
 {
        return page_to_pfn(virt_to_page(addr));
 }
@@ -252,10 +285,17 @@ EXPORT_SYMBOL(vmalloc_32);
  *
  * The resulting memory area is 32bit addressable and zeroed so it can be
  * mapped to userspace without leaking data.
+ *
+ * VM_USERMAP is set on the corresponding VMA so that subsequent calls to
+ * remap_vmalloc_range() are permissible.
  */
 void *vmalloc_32_user(unsigned long size)
 {
-       return __vmalloc(size, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL);
+       /*
+        * We'll have to sort out the ZONE_DMA bits for 64-bit,
+        * but for now this can simply use vmalloc_user() directly.
+        */
+       return vmalloc_user(size);
 }
 EXPORT_SYMBOL(vmalloc_32_user);
 
@@ -266,7 +306,7 @@ void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_
 }
 EXPORT_SYMBOL(vmap);
 
-void vunmap(void *addr)
+void vunmap(const void *addr)
 {
        BUG();
 }
@@ -828,6 +868,9 @@ unsigned long do_mmap_pgoff(struct file *file,
        void *result;
        int ret;
 
+       if (!(flags & MAP_FIXED))
+               addr = round_hint_to_min(addr);
+
        /* decide whether we should attempt the mapping, and if so what sort of
         * mapping */
        ret = validate_mmap_request(file, addr, len, prot, flags, pgoff,
@@ -930,8 +973,13 @@ unsigned long do_mmap_pgoff(struct file *file,
 
        INIT_LIST_HEAD(&vma->anon_vma_node);
        atomic_set(&vma->vm_usage, 1);
-       if (file)
+       if (file) {
                get_file(file);
+               if (vm_flags & VM_EXECUTABLE) {
+                       added_exe_file_vma(current->mm);
+                       vma->vm_mm = current->mm;
+               }
+       }
        vma->vm_file    = file;
        vma->vm_flags   = vm_flags;
        vma->vm_start   = addr;
@@ -986,8 +1034,11 @@ unsigned long do_mmap_pgoff(struct file *file,
        up_write(&nommu_vma_sem);
        kfree(vml);
        if (vma) {
-               if (vma->vm_file)
+               if (vma->vm_file) {
                        fput(vma->vm_file);
+                       if (vma->vm_flags & VM_EXECUTABLE)
+                               removed_exe_file_vma(vma->vm_mm);
+               }
                kfree(vma);
        }
        return ret;
@@ -1017,7 +1068,7 @@ EXPORT_SYMBOL(do_mmap_pgoff);
 /*
  * handle mapping disposal for uClinux
  */
-static void put_vma(struct vm_area_struct *vma)
+static void put_vma(struct mm_struct *mm, struct vm_area_struct *vma)
 {
        if (vma) {
                down_write(&nommu_vma_sem);
@@ -1039,8 +1090,11 @@ static void put_vma(struct vm_area_struct *vma)
                        realalloc -= kobjsize(vma);
                        askedalloc -= sizeof(*vma);
 
-                       if (vma->vm_file)
+                       if (vma->vm_file) {
                                fput(vma->vm_file);
+                               if (vma->vm_flags & VM_EXECUTABLE)
+                                       removed_exe_file_vma(mm);
+                       }
                        kfree(vma);
                }
 
@@ -1077,7 +1131,7 @@ int do_munmap(struct mm_struct *mm, unsigned long addr, size_t len)
  found:
        vml = *parent;
 
-       put_vma(vml->vma);
+       put_vma(mm, vml->vma);
 
        *parent = vml->next;
        realalloc -= kobjsize(vml);
@@ -1122,7 +1176,7 @@ void exit_mmap(struct mm_struct * mm)
 
                while ((tmp = mm->context.vmlist)) {
                        mm->context.vmlist = tmp->next;
-                       put_vma(tmp->vma);
+                       put_vma(mm, tmp->vma);
 
                        realalloc -= kobjsize(tmp);
                        askedalloc -= sizeof(*tmp);
@@ -1212,6 +1266,21 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
 }
 EXPORT_SYMBOL(remap_pfn_range);
 
+int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
+                       unsigned long pgoff)
+{
+       unsigned int size = vma->vm_end - vma->vm_start;
+
+       if (!(vma->vm_flags & VM_USERMAP))
+               return -EINVAL;
+
+       vma->vm_start = (unsigned long)(addr + (pgoff << PAGE_SHIFT));
+       vma->vm_end = vma->vm_start + size;
+
+       return 0;
+}
+EXPORT_SYMBOL(remap_vmalloc_range);
+
 void swap_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
 {
 }
@@ -1348,7 +1417,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
         * cast `allowed' as a signed long because vm_committed_space
         * sometimes has a negative value
         */
-       if (atomic_read(&vm_committed_space) < (long)allowed)
+       if (atomic_long_read(&vm_committed_space) < (long)allowed)
                return 0;
 error:
        vm_unacct_memory(pages);