Move the u-area allocation and pmap-magic logic to its own function

uvm_uarea_alloc()

function name from NetBSD; arm testing by miod@

diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index bad4221..da052e8 100644 (file)
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: kern_fork.c,v 1.163 2014/04/18 11:51:17 guenther Exp $        */
+/*     $OpenBSD: kern_fork.c,v 1.164 2014/05/03 22:44:36 guenther Exp $        */
 /*     $NetBSD: kern_fork.c,v 1.29 1996/02/09 18:59:34 christos Exp $  */
 
 /*
@@ -287,10 +287,7 @@ fork1(struct proc *curp, int flags, void *stack, pid_t *tidptr,
                }
        }
 
-       uaddr = uvm_km_kmemalloc_pla(kernel_map, uvm.kernel_object, USPACE,
-           USPACE_ALIGN, UVM_KMF_ZERO,
-           no_constraint.ucr_low, no_constraint.ucr_high,
-           0, 0, USPACE/PAGE_SIZE);
+       uaddr = uvm_uarea_alloc();
        if (uaddr == 0) {
                if ((flags & FORK_THREAD) == 0) {
                        (void)chgproccnt(uid, -1);

diff --git a/sys/uvm/uvm_extern.h b/sys/uvm/uvm_extern.h
index 06919d7..d6eae9c 100644 (file)
--- a/sys/uvm/uvm_extern.h
+++ b/sys/uvm/uvm_extern.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: uvm_extern.h,v 1.112 2014/04/03 21:40:10 tedu Exp $   */
+/*     $OpenBSD: uvm_extern.h,v 1.113 2014/05/03 22:44:36 guenther Exp $       */
 /*     $NetBSD: uvm_extern.h,v 1.57 2001/03/09 01:02:12 chs Exp $      */
 
 /*
@@ -513,6 +513,7 @@ int                 uvm_fault(vm_map_t, vaddr_t,
 #if defined(KGDB)
 void                   uvm_chgkprot(caddr_t, size_t, int);
 #endif
+vaddr_t                        uvm_uarea_alloc(void);
 void                   uvm_fork(struct proc *, struct proc *, boolean_t,
                            void *, size_t, void (*)(void *), void *);
 void                   uvm_exit(struct proc *);

diff --git a/sys/uvm/uvm_glue.c b/sys/uvm/uvm_glue.c
index ffb283f..324794c 100644 (file)
--- a/sys/uvm/uvm_glue.c
+++ b/sys/uvm/uvm_glue.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: uvm_glue.c,v 1.62 2014/04/13 23:14:15 tedu Exp $      */
+/*     $OpenBSD: uvm_glue.c,v 1.63 2014/05/03 22:44:36 guenther Exp $  */
 /*     $NetBSD: uvm_glue.c,v 1.44 2001/02/06 19:54:44 eeh Exp $        */
 
 /* 
@@ -293,12 +293,32 @@ uvm_vsunlock_device(struct proc *p, void *addr, size_t len, void *map)
        uvm_km_free(kernel_map, kva, sz);
 }
 
+/*
+ * uvm_uarea_alloc: allocate the u-area for a new thread
+ */
+vaddr_t
+uvm_uarea_alloc(void)
+{
+       vaddr_t uaddr;
+
+       uaddr = uvm_km_kmemalloc_pla(kernel_map, uvm.kernel_object, USPACE,
+           USPACE_ALIGN, UVM_KMF_ZERO,
+           no_constraint.ucr_low, no_constraint.ucr_high,
+           0, 0, USPACE/PAGE_SIZE);
+ 
+#ifdef PMAP_UAREA
+       /* Tell the pmap this is a u-area mapping */
+       if (uaddr != 0)
+               PMAP_UAREA(uaddr);
+#endif
+
+       return (uaddr);
+}
+
 /*
  * uvm_fork: fork a virtual address space
  *
  * - the address space is copied as per parent map's inherit values
- * - a new "user" structure is allocated for the child process
- *     [filled in by MD layer...]
  * - if specified, the child gets a new user stack described by
  *     stack and stacksize
  * - NOTE: the kernel stack may be at a different location in the child
@@ -318,11 +338,6 @@ uvm_fork(struct proc *p1, struct proc *p2, boolean_t shared, void *stack,
        } else
                p2->p_vmspace = uvmspace_fork(p1->p_vmspace); /* fork vmspace */
 
-#ifdef PMAP_UAREA
-       /* Tell the pmap this is a u-area mapping */
-       PMAP_UAREA((vaddr_t)p2->p_addr);
-#endif
-
        /*
         * cpu_fork() copy and update the pcb, and make the child ready
         * to run.  If this is a normal user fork, the child will exit