X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=mm%2Fmmap.c;h=c1868ecdbc5facfd8ba25835e71e05cfee9d9680;hb=120cd57644f85b280b538ee403423641167913a9;hp=4f5b5709136abbe6c08b306ac35ac92740cb04d8;hpb=3661f00e2097676847deb01add1a0918044bd816;p=linux-2.6-omap-h63xx.git

diff --git a/mm/mmap.c b/mm/mmap.c
index 4f5b5709136..c1868ecdbc5 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -96,7 +96,7 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
 	if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
 		unsigned long n;
 
-		free = get_page_cache_size();
+		free = global_page_state(NR_FILE_PAGES);
 		free += nr_swap_pages;
 
 		/*
@@ -121,14 +121,26 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
 		 * only call if we're about to fail.
 		 */
 		n = nr_free_pages();
+
+		/*
+		 * Leave reserved pages. The pages are not for anonymous pages.
+		 */
+		if (n <= totalreserve_pages)
+			goto error;
+		else
+			n -= totalreserve_pages;
+
+		/*
+		 * Leave the last 3% for root
+		 */
 		if (!cap_sys_admin)
 			n -= n / 32;
 		free += n;
 
 		if (free > pages)
 			return 0;
-		vm_unacct_memory(pages);
-		return -ENOMEM;
+
+		goto error;
 	}
 
 	allowed = (totalram_pages - hugetlb_total_pages())
@@ -150,7 +162,7 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
 	 */
 	if (atomic_read(&vm_committed_space) < (long)allowed)
 		return 0;
-
+error:
 	vm_unacct_memory(pages);
 
 	return -ENOMEM;
@@ -220,6 +232,17 @@ asmlinkage unsigned long sys_brk(unsigned long brk)
 
 	if (brk < mm->end_code)
 		goto out;
+
+	/*
+	 * Check against rlimit here. If this check is done later after the test
+	 * of oldbrk with newbrk then it can escape the test and let the data
+	 * segment grow beyond its set limit the in case where the limit is
+	 * not page aligned -Ram Gupta
+	 */
+	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
+	if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
+		goto out;
+
 	newbrk = PAGE_ALIGN(brk);
 	oldbrk = PAGE_ALIGN(mm->brk);
 	if (oldbrk == newbrk)
@@ -232,11 +255,6 @@ asmlinkage unsigned long sys_brk(unsigned long brk)
 		goto out;
 	}
 
-	/* Check against rlimit.. */
-	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
-	if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
-		goto out;
-
 	/* Check against existing mmap mappings. */
 	if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
 		goto out;
@@ -294,8 +312,7 @@ void validate_mm(struct mm_struct *mm)
 	i = browse_rb(&mm->mm_rb);
 	if (i != mm->map_count)
 		printk("map_count %d rb %d\n", mm->map_count, i), bug = 1;
-	if (bug)
-		BUG();
+	BUG_ON(bug);
 }
 #else
 #define validate_mm(mm) do { } while (0)
@@ -432,8 +449,7 @@ __insert_vm_struct(struct mm_struct * mm, struct vm_area_struct * vma)
 	struct rb_node ** rb_link, * rb_parent;
 
 	__vma = find_vma_prepare(mm, vma->vm_start,&prev, &rb_link, &rb_parent);
-	if (__vma && __vma->vm_start < vma->vm_end)
-		BUG();
+	BUG_ON(__vma && __vma->vm_start < vma->vm_end);
 	__vma_link(mm, vma, prev, rb_link, rb_parent);
 	mm->map_count++;
 }
@@ -813,8 +829,7 @@ try_prev:
 	 * (e.g. stash info in next's anon_vma_node when assigning
 	 * an anon_vma, or when trying vma_merge).  Another time.
 	 */
-	if (find_vma_prev(vma->vm_mm, vma->vm_start, &near) != vma)
-		BUG();
+	BUG_ON(find_vma_prev(vma->vm_mm, vma->vm_start, &near) != vma);
 	if (!near)
 		goto none;
 
@@ -1050,7 +1065,8 @@ munmap_back:
 	vma->vm_start = addr;
 	vma->vm_end = addr + len;
 	vma->vm_flags = vm_flags;
-	vma->vm_page_prot = protection_map[vm_flags & 0x0f];
+	vma->vm_page_prot = protection_map[vm_flags &
+				(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
 	vma->vm_pgoff = pgoff;
 
 	if (file) {
@@ -1074,6 +1090,12 @@ munmap_back:
 			goto free_vma;
 	}
 
+	/* Don't make the VMA automatically writable if it's shared, but the
+	 * backer wishes to know when pages are first written to */
+	if (vma->vm_ops && vma->vm_ops->page_mkwrite)
+		vma->vm_page_prot =
+			protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC)];
+
 	/* We set VM_ACCOUNT in a shared mapping's vm_flags, to inform
 	 * shmem_zero_setup (perhaps called through /dev/zero's ->mmap)
 	 * that memory reservation must be checked; but that reservation
@@ -1906,7 +1928,8 @@ 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 & 0x0f];
+	vma->vm_page_prot = protection_map[flags &
+				(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
 	vma_link(mm, vma, prev, rb_link, rb_parent);
 out:
 	mm->total_vm += len >> PAGE_SHIFT;