X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=mm%2Fmmap.c;h=e66a0b524affef544588a8c4f8a92d3473b79a34;hb=c547fc28ab3e8716076fdaf4bd0260c5d63a18f7;hp=e6ee12344b139274325a1db834da1de6cf334da1;hpb=3145012c1c34a3504a2234bd2034ca6ea4767bc5;p=powerpc.git

diff --git a/mm/mmap.c b/mm/mmap.c
index e6ee12344b..e66a0b524a 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -30,6 +30,10 @@
 #include <asm/cacheflush.h>
 #include <asm/tlb.h>
 
+#ifndef arch_mmap_check
+#define arch_mmap_check(addr, len, flags)	(0)
+#endif
+
 static void unmap_region(struct mm_struct *mm,
 		struct vm_area_struct *vma, struct vm_area_struct *prev,
 		unsigned long start, unsigned long end);
@@ -96,7 +100,7 @@ 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;
 
 		/*
@@ -913,6 +917,10 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
 	if (!len)
 		return -EINVAL;
 
+	error = arch_mmap_check(addr, len, flags);
+	if (error)
+		return error;
+
 	/* Careful about overflows.. */
 	len = PAGE_ALIGN(len);
 	if (!len || len > TASK_SIZE)
@@ -1065,7 +1073,8 @@ 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) {
@@ -1089,6 +1098,12 @@ 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
@@ -1852,6 +1867,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
 	unsigned long flags;
 	struct rb_node ** rb_link, * rb_parent;
 	pgoff_t pgoff = addr >> PAGE_SHIFT;
+	int error;
 
 	len = PAGE_ALIGN(len);
 	if (!len)
@@ -1860,6 +1876,12 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
 	if ((addr + len) > TASK_SIZE || (addr + len) < addr)
 		return -EINVAL;
 
+	flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
+
+	error = arch_mmap_check(addr, len, flags);
+	if (error)
+		return error;
+
 	/*
 	 * mlock MCL_FUTURE?
 	 */
@@ -1900,8 +1922,6 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
 	if (security_vm_enough_memory(len >> PAGE_SHIFT))
 		return -ENOMEM;
 
-	flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
-
 	/* Can we just expand an old private anonymous mapping? */
 	if (vma_merge(mm, prev, addr, addr + len, flags,
 					NULL, NULL, pgoff, NULL))
@@ -1921,7 +1941,8 @@ 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;