patch-2.3.99-pre6 linux/mm/mmap.c

• Lines: 161
• Date: Wed Apr 26 09:11:32 2000
• Orig file: v2.3.99-pre5/linux/mm/mmap.c
• Orig date: Mon Mar 27 08:08:33 2000

diff -u --recursive --new-file v2.3.99-pre5/linux/mm/mmap.c linux/mm/mmap.c
@@ -110,7 +110,7 @@
 
 	/* Always allow shrinking brk. */
 	if (brk <= mm->brk) {
-		if (!do_munmap(newbrk, oldbrk-newbrk))
+		if (!do_munmap(mm, newbrk, oldbrk-newbrk))
 			goto set_brk;
 		goto out;
 	}
@@ -220,8 +220,7 @@
 		default:
 			return -EINVAL;
 		}
-	} else if ((flags & MAP_TYPE) != MAP_PRIVATE)
-		return -EINVAL;
+	}
 
 	/* Obtain the address to map to. we verify (or select) it and ensure
 	 * that it represents a valid section of the address space.
@@ -269,8 +268,11 @@
 			if (!(file->f_mode & FMODE_WRITE))
 				vma->vm_flags &= ~(VM_MAYWRITE | VM_SHARED);
 		}
-	} else
+	} else {
 		vma->vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
+		if (flags & MAP_SHARED)
+			vma->vm_flags |= VM_SHARED | VM_MAYSHARE;
+	}
 	vma->vm_page_prot = protection_map[vma->vm_flags & 0x0f];
 	vma->vm_ops = NULL;
 	vma->vm_pgoff = pgoff;
@@ -279,7 +281,7 @@
 
 	/* Clear old maps */
 	error = -ENOMEM;
-	if (do_munmap(addr, len))
+	if (do_munmap(mm, addr, len))
 		goto free_vma;
 
 	/* Check against address space limit. */
@@ -316,6 +318,8 @@
 			atomic_inc(&file->f_dentry->d_inode->i_writecount);
 		if (error)
 			goto unmap_and_free_vma;
+	} else if (flags & MAP_SHARED) {
+		error = map_zero_setup(vma);
 	}
 
 	/*
@@ -468,13 +472,13 @@
 	return NULL;
 }
 
-struct vm_area_struct * find_extend_vma(struct task_struct * tsk, unsigned long addr)
+struct vm_area_struct * find_extend_vma(struct mm_struct * mm, unsigned long addr)
 {
 	struct vm_area_struct * vma;
 	unsigned long start;
 
 	addr &= PAGE_MASK;
-	vma = find_vma(tsk->mm,addr);
+	vma = find_vma(mm,addr);
 	if (!vma)
 		return NULL;
 	if (vma->vm_start <= addr)
@@ -513,8 +517,9 @@
  * allocate a new one, and the return indicates whether the old
  * area was reused.
  */
-static struct vm_area_struct * unmap_fixup(struct vm_area_struct *area,
-	unsigned long addr, size_t len, struct vm_area_struct *extra)
+static struct vm_area_struct * unmap_fixup(struct mm_struct *mm, 
+	struct vm_area_struct *area, unsigned long addr, size_t len, 
+	struct vm_area_struct *extra)
 {
 	struct vm_area_struct *mpnt;
 	unsigned long end = addr + len;
@@ -536,11 +541,11 @@
 	/* Work out to one of the ends. */
 	if (end == area->vm_end) {
 		area->vm_end = addr;
-		vmlist_modify_lock(current->mm);
+		vmlist_modify_lock(mm);
 	} else if (addr == area->vm_start) {
 		area->vm_pgoff += (end - area->vm_start) >> PAGE_SHIFT;
 		area->vm_start = end;
-		vmlist_modify_lock(current->mm);
+		vmlist_modify_lock(mm);
 	} else {
 	/* Unmapping a hole: area->vm_start < addr <= end < area->vm_end */
 		/* Add end mapping -- leave beginning for below */
@@ -562,12 +567,12 @@
 		if (mpnt->vm_ops && mpnt->vm_ops->open)
 			mpnt->vm_ops->open(mpnt);
 		area->vm_end = addr;	/* Truncate area */
-		vmlist_modify_lock(current->mm);
-		insert_vm_struct(current->mm, mpnt);
+		vmlist_modify_lock(mm);
+		insert_vm_struct(mm, mpnt);
 	}
 
-	insert_vm_struct(current->mm, area);
-	vmlist_modify_unlock(current->mm);
+	insert_vm_struct(mm, area);
+	vmlist_modify_unlock(mm);
 	return extra;
 }
 
@@ -634,9 +639,8 @@
  * work.  This now handles partial unmappings.
  * Jeremy Fitzhardine <jeremy@sw.oz.au>
  */
-int do_munmap(unsigned long addr, size_t len)
+int do_munmap(struct mm_struct *mm, unsigned long addr, size_t len)
 {
-	struct mm_struct * mm;
 	struct vm_area_struct *mpnt, *prev, **npp, *free, *extra;
 
 	if ((addr & ~PAGE_MASK) || addr > TASK_SIZE || len > TASK_SIZE-addr)
@@ -650,7 +654,6 @@
 	 * every area affected in some way (by any overlap) is put
 	 * on the list.  If nothing is put on, nothing is affected.
 	 */
-	mm = current->mm;
 	mpnt = find_vma_prev(mm, addr, &prev);
 	if (!mpnt)
 		return 0;
@@ -713,7 +716,7 @@
 		/*
 		 * Fix the mapping, and free the old area if it wasn't reused.
 		 */
-		extra = unmap_fixup(mpnt, st, size, extra);
+		extra = unmap_fixup(mm, mpnt, st, size, extra);
 	}
 
 	/* Release the extra vma struct if it wasn't used */
@@ -728,10 +731,11 @@
 asmlinkage long sys_munmap(unsigned long addr, size_t len)
 {
 	int ret;
+	struct mm_struct *mm = current->mm;
 
-	down(&current->mm->mmap_sem);
-	ret = do_munmap(addr, len);
-	up(&current->mm->mmap_sem);
+	down(&mm->mmap_sem);
+	ret = do_munmap(mm, addr, len);
+	up(&mm->mmap_sem);
 	return ret;
 }
 
@@ -763,7 +767,7 @@
 	/*
 	 * Clear old maps.  this also does some error checking for us
 	 */
-	retval = do_munmap(addr, len);
+	retval = do_munmap(mm, addr, len);
 	if (retval != 0)
 		return retval;