[src/trunk]: src/sys/uvm Revert "mmap(2): If we fail with a hint, try again w...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0e9ba4889c9b
branches:  trunk
changeset: 365713:0e9ba4889c9b
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Tue Apr 19 22:53:34 2022 +0000

description:
Revert "mmap(2): If we fail with a hint, try again without it."

This doesn't work, because uvm_mmap releases the uobj when it fails.
Should factor this more coherently, but let's just revert for now.

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diffstat:

 sys/uvm/uvm_mmap.c |  26 ++++----------------------
 1 files changed, 4 insertions(+), 22 deletions(-)

diffs (64 lines):

diff -r 2336a9f2fd96 -r 0e9ba4889c9b sys/uvm/uvm_mmap.c
--- a/sys/uvm/uvm_mmap.c        Tue Apr 19 22:40:45 2022 +0000
+++ b/sys/uvm/uvm_mmap.c        Tue Apr 19 22:53:34 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_mmap.c,v 1.178 2022/04/19 01:34:52 riastradh Exp $ */
+/*     $NetBSD: uvm_mmap.c,v 1.179 2022/04/19 22:53:34 riastradh Exp $ */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -46,7 +46,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_mmap.c,v 1.178 2022/04/19 01:34:52 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_mmap.c,v 1.179 2022/04/19 22:53:34 riastradh Exp $");
 
 #include "opt_compat_netbsd.h"
 #include "opt_pax.h"
@@ -277,8 +277,7 @@
        vsize_t size, pageoff, newsize;
        vm_prot_t prot, maxprot, extraprot;
        int flags, fd, advice;
-       vaddr_t defaddr = 0;    /* XXXGCC */
-       bool addrhint = false;
+       vaddr_t defaddr;
        struct file *fp = NULL;
        struct uvm_object *uobj;
        int error;
@@ -350,12 +349,6 @@
                        addr = MAX(addr, defaddr);
                else
                        addr = MIN(addr, defaddr);
-
-               /*
-                * If addr is nonzero and not the default, then the
-                * address is a hint.
-                */
-               addrhint = (addr != 0 && addr != defaddr);
        }
 
        /*
@@ -408,21 +401,10 @@
        /*
         * now let kernel internal function uvm_mmap do the work.
         */
+
        error = uvm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot,
            flags, advice, uobj, pos, p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur);
 
-       /*
-        * If the user provided a hint, and we couldn't satisfy that
-        * hint, try again with the default address.
-        */
-       if (error && addrhint) {
-               addr = defaddr;
-               pax_aslr_mmap(l, &addr, orig_addr, flags);
-               error = uvm_mmap(&p->p_vmspace->vm_map, &addr, size, prot,
-                   maxprot, flags, advice, uobj, pos,
-                   p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur);
-       }
-
        /* remember to add offset */
        *retval = (register_t)(addr + pageoff);