X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=mm%2Fmmap.c;h=facc1a75bd4fdbc9f274dbc26a7e536f0eb8f561;hb=37e58df30063e229ee5157f9d1c1fa1d749917c2;hp=7afc7a7cec6f681001817ad6656d3a20d9ed53a7;hpb=2e85622042cb5fd56a606e884651ffde52f21028;p=profile%2Fivi%2Fkernel-adaptation-intel-automotive.git

diff --git a/mm/mmap.c b/mm/mmap.c
index 7afc7a7..facc1a7 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/slab.h>
+#include <linux/backing-dev.h>
 #include <linux/mm.h>
 #include <linux/shm.h>
 #include <linux/mman.h>
@@ -93,7 +94,7 @@ atomic_t vm_committed_space = ATOMIC_INIT(0);
  * Note this is a helper function intended to be used by LSMs which
  * wish to use this logic.
  */
-int __vm_enough_memory(long pages, int cap_sys_admin)
+int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
 {
 	unsigned long free, allowed;
 
@@ -166,7 +167,7 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
 
 	/* Don't let a single process grow too big:
 	   leave 3% of the size of this process for other processes */
-	allowed -= current->mm->total_vm / 32;
+	allowed -= mm->total_vm / 32;
 
 	/*
 	 * cast `allowed' as a signed long because vm_committed_space
@@ -180,8 +181,6 @@ error:
 	return -ENOMEM;
 }
 
-EXPORT_SYMBOL(__vm_enough_memory);
-
 /*
  * Requires inode->i_mapping->i_mmap_lock
  */
@@ -1029,6 +1028,39 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
 }
 EXPORT_SYMBOL(do_mmap_pgoff);
 
+/*
+ * Some shared mappigns will want the pages marked read-only
+ * to track write events. If so, we'll downgrade vm_page_prot
+ * to the private version (using protection_map[] without the
+ * VM_SHARED bit).
+ */
+int vma_wants_writenotify(struct vm_area_struct *vma)
+{
+	unsigned int vm_flags = vma->vm_flags;
+
+	/* If it was private or non-writable, the write bit is already clear */
+	if ((vm_flags & (VM_WRITE|VM_SHARED)) != ((VM_WRITE|VM_SHARED)))
+		return 0;
+
+	/* The backer wishes to know when pages are first written to? */
+	if (vma->vm_ops && vma->vm_ops->page_mkwrite)
+		return 1;
+
+	/* The open routine did something to the protections already? */
+	if (pgprot_val(vma->vm_page_prot) !=
+	    pgprot_val(vm_get_page_prot(vm_flags)))
+		return 0;
+
+	/* Specialty mapping? */
+	if (vm_flags & (VM_PFNMAP|VM_INSERTPAGE))
+		return 0;
+
+	/* Can the mapping track the dirty pages? */
+	return vma->vm_file && vma->vm_file->f_mapping &&
+		mapping_cap_account_dirty(vma->vm_file->f_mapping);
+}
+
+
 unsigned long mmap_region(struct file *file, unsigned long addr,
 			  unsigned long len, unsigned long flags,
 			  unsigned int vm_flags, unsigned long pgoff,
@@ -1097,8 +1129,7 @@ munmap_back:
 	vma->vm_start = addr;
 	vma->vm_end = addr + len;
 	vma->vm_flags = vm_flags;
-	vma->vm_page_prot = protection_map[vm_flags &
-				(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
+	vma->vm_page_prot = vm_get_page_prot(vm_flags);
 	vma->vm_pgoff = pgoff;
 
 	if (file) {
@@ -1140,8 +1171,7 @@ munmap_back:
 	vm_flags = vma->vm_flags;
 
 	if (vma_wants_writenotify(vma))
-		vma->vm_page_prot =
-			protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC)];
+		vma->vm_page_prot = vm_get_page_prot(vm_flags & ~VM_SHARED);
 
 	if (!file || !vma_merge(mm, prev, addr, vma->vm_end,
 			vma->vm_flags, NULL, file, pgoff, vma_policy(vma))) {
@@ -1969,8 +1999,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
 	vma->vm_end = addr + len;
 	vma->vm_pgoff = pgoff;
 	vma->vm_flags = flags;
-	vma->vm_page_prot = protection_map[flags &
-				(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
+	vma->vm_page_prot = vm_get_page_prot(flags);
 	vma_link(mm, vma, prev, rb_link, rb_parent);
 out:
 	mm->total_vm += len >> PAGE_SHIFT;
@@ -2043,7 +2072,7 @@ int insert_vm_struct(struct mm_struct * mm, struct vm_area_struct * vma)
 	if (__vma && __vma->vm_start < vma->vm_end)
 		return -ENOMEM;
 	if ((vma->vm_flags & VM_ACCOUNT) &&
-	     security_vm_enough_memory(vma_pages(vma)))
+	     security_vm_enough_memory_mm(mm, vma_pages(vma)))
 		return -ENOMEM;
 	vma_link(mm, vma, prev, rb_link, rb_parent);
 	return 0;
@@ -2176,7 +2205,7 @@ int install_special_mapping(struct mm_struct *mm,
 	vma->vm_end = addr + len;
 
 	vma->vm_flags = vm_flags | mm->def_flags;
-	vma->vm_page_prot = protection_map[vma->vm_flags & 7];
+	vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 
 	vma->vm_ops = &special_mapping_vmops;
 	vma->vm_private_data = pages;