X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fnommu.c;h=b76f3ee0abe015a85f36ff4b2599cff21d3c3efd;hb=eac4068013a067f5fb63005033c13b27fbf6dfca;hp=b9b5cceb1b68261b3c88760a6e0a56d1d626818c;hpb=c08c6e1f54c85fc299cf9f88cf330d6dd28a9a1d;p=safe%2Fjmp%2Flinux-2.6

diff --git a/mm/nommu.c b/mm/nommu.c
index b9b5cce..b76f3ee 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -146,7 +146,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 			(VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
 
 	for (i = 0; i < nr_pages; i++) {
-		vma = find_extend_vma(mm, start);
+		vma = find_vma(mm, start);
 		if (!vma)
 			goto finish_or_fault;
 
@@ -162,7 +162,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 		}
 		if (vmas)
 			vmas[i] = vma;
-		start += PAGE_SIZE;
+		start = (start + PAGE_SIZE) & PAGE_MASK;
 	}
 
 	return i;
@@ -764,7 +764,7 @@ EXPORT_SYMBOL(find_vma);
  */
 struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr)
 {
-	return find_vma(mm, addr & PAGE_MASK);
+	return find_vma(mm, addr);
 }
 
 /*
@@ -918,14 +918,6 @@ static int validate_mmap_request(struct file *file,
 			if (!(capabilities & BDI_CAP_MAP_DIRECT))
 				return -ENODEV;
 
-			if (((prot & PROT_READ)  && !(capabilities & BDI_CAP_READ_MAP))  ||
-			    ((prot & PROT_WRITE) && !(capabilities & BDI_CAP_WRITE_MAP)) ||
-			    ((prot & PROT_EXEC)  && !(capabilities & BDI_CAP_EXEC_MAP))
-			    ) {
-				printk("MAP_SHARED not completely supported on !MMU\n");
-				return -EINVAL;
-			}
-
 			/* we mustn't privatise shared mappings */
 			capabilities &= ~BDI_CAP_MAP_COPY;
 		}
@@ -941,6 +933,20 @@ static int validate_mmap_request(struct file *file,
 				capabilities &= ~BDI_CAP_MAP_DIRECT;
 		}
 
+		if (capabilities & BDI_CAP_MAP_DIRECT) {
+			if (((prot & PROT_READ)  && !(capabilities & BDI_CAP_READ_MAP))  ||
+			    ((prot & PROT_WRITE) && !(capabilities & BDI_CAP_WRITE_MAP)) ||
+			    ((prot & PROT_EXEC)  && !(capabilities & BDI_CAP_EXEC_MAP))
+			    ) {
+				capabilities &= ~BDI_CAP_MAP_DIRECT;
+				if (flags & MAP_SHARED) {
+					printk(KERN_WARNING
+					       "MAP_SHARED not completely supported on !MMU\n");
+					return -EINVAL;
+				}
+			}
+		}
+
 		/* handle executable mappings and implied executable
 		 * mappings */
 		if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) {
@@ -996,22 +1002,20 @@ static unsigned long determine_vm_flags(struct file *file,
 	unsigned long vm_flags;
 
 	vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags);
-	vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
 	/* vm_flags |= mm->def_flags; */
 
 	if (!(capabilities & BDI_CAP_MAP_DIRECT)) {
 		/* attempt to share read-only copies of mapped file chunks */
+		vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
 		if (file && !(prot & PROT_WRITE))
 			vm_flags |= VM_MAYSHARE;
-	}
-	else {
+	} else {
 		/* overlay a shareable mapping on the backing device or inode
 		 * if possible - used for chardevs, ramfs/tmpfs/shmfs and
 		 * romfs/cramfs */
+		vm_flags |= VM_MAYSHARE | (capabilities & BDI_CAP_VMFLAGS);
 		if (flags & MAP_SHARED)
-			vm_flags |= VM_MAYSHARE | VM_SHARED;
-		else if ((((vm_flags & capabilities) ^ vm_flags) & BDI_CAP_VMFLAGS) == 0)
-			vm_flags |= VM_MAYSHARE;
+			vm_flags |= VM_SHARED;
 	}
 
 	/* refuse to let anyone share private mappings with this process if
@@ -1040,10 +1044,9 @@ static int do_mmap_shared_file(struct vm_area_struct *vma)
 	if (ret != -ENOSYS)
 		return ret;
 
-	/* getting an ENOSYS error indicates that direct mmap isn't
-	 * possible (as opposed to tried but failed) so we'll fall
-	 * through to making a private copy of the data and mapping
-	 * that if we can */
+	/* getting -ENOSYS indicates that direct mmap isn't possible (as
+	 * opposed to tried but failed) so we can only give a suitable error as
+	 * it's not possible to make a private copy if MAP_SHARED was given */
 	return -ENODEV;
 }
 
@@ -1428,6 +1431,30 @@ out:
 	return retval;
 }
 
+#ifdef __ARCH_WANT_SYS_OLD_MMAP
+struct mmap_arg_struct {
+	unsigned long addr;
+	unsigned long len;
+	unsigned long prot;
+	unsigned long flags;
+	unsigned long fd;
+	unsigned long offset;
+};
+
+SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg)
+{
+	struct mmap_arg_struct a;
+
+	if (copy_from_user(&a, arg, sizeof(a)))
+		return -EFAULT;
+	if (a.offset & ~PAGE_MASK)
+		return -EINVAL;
+
+	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+			      a.offset >> PAGE_SHIFT);
+}
+#endif /* __ARCH_WANT_SYS_OLD_MMAP */
+
 /*
  * split a vma into two pieces at address 'addr', a new vma is allocated either
  * for the first part or the tail.