hurd: Remove optimizing anonymous maps as __vm_allocate.

Optimizing anonymous maps brings bugs, and does not optimize much anyway.

	[BZ #19903]
	* sysdeps/mach/hurd/mmap.c (__mmap): Remove optimizing anonymous maps
	as __vm_allocate.

diff --git a/ChangeLog b/ChangeLog
index afd99a634ee662c1743da674da73f9287489cd86..98a86369d524b127c311659fbbbf5018166dfe0a 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -20,6 +20,10 @@
        EBADF case, or else POLLERR.
        - On error, make select simulated readiness.
 
+       [BZ #19903]
+       * sysdeps/mach/hurd/mmap.c (__mmap): Remove optimizing anonymous maps
+       as __vm_allocate.
+
 2019-08-30  Richard Braun  <rbraun@sceen.net>
 
        * hurd/hurdselect.c (_hurd_select): Always call __io_select with no

diff --git a/sysdeps/mach/hurd/mmap.c b/sysdeps/mach/hurd/mmap.c
index 8eb741f7e112425c96e5fa7c3e89d2f27a3e2686..e3ff77d6c90a51131f17c06cf97c9ad273da7ef8 100644 (file)
--- a/sysdeps/mach/hurd/mmap.c
+++ b/sysdeps/mach/hurd/mmap.c
@@ -44,29 +44,6 @@ __mmap (void *addr, size_t len, int prot, int flags, int fd, off_t offset)
   if ((mapaddr & (__vm_page_size - 1)) || (offset & (__vm_page_size - 1)))
     return (void *) (long int) __hurd_fail (EINVAL);
 
-  if ((flags & (MAP_TYPE|MAP_INHERIT)) == MAP_ANON
-      && prot == (PROT_READ|PROT_WRITE)) /* cf VM_PROT_DEFAULT */
-    {
-      /* vm_allocate has (a little) less overhead in the kernel too.  */
-      err = __vm_allocate (__mach_task_self (), &mapaddr, len, mapaddr == 0);
-
-      if (err == KERN_NO_SPACE)
-       {
-         if (flags & MAP_FIXED)
-           {
-             /* XXX this is not atomic as it is in unix! */
-             /* The region is already allocated; deallocate it first.  */
-             err = __vm_deallocate (__mach_task_self (), mapaddr, len);
-             if (!err)
-               err = __vm_allocate (__mach_task_self (), &mapaddr, len, 0);
-           }
-         else if (mapaddr != 0)
-           err = __vm_allocate (__mach_task_self (), &mapaddr, len, 1);
-       }
-
-      return err ? (void *) (long int) __hurd_fail (err) : (void *) mapaddr;
-    }
-
   vmprot = VM_PROT_NONE;
   if (prot & PROT_READ)
     vmprot |= VM_PROT_READ;