[src/trunk]: src/sys/fs/tmpfs Constify, update some comments, use memset() to...

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

details:   https://anonhg.NetBSD.org/src/rev/6471d0493a52
branches:  trunk
changeset: 764752:6471d0493a52
user:      rmind <rmind%NetBSD.org@localhost>
date:      Mon May 02 23:42:10 2011 +0000

description:
Constify, update some comments, use memset() to clear pgs.

diffstat:

 sys/fs/tmpfs/tmpfs_vnops.c |  92 +++++++++++++++++++++++----------------------
 1 files changed, 47 insertions(+), 45 deletions(-)

diffs (154 lines):

diff -r ad23a4100f1d -r 6471d0493a52 sys/fs/tmpfs/tmpfs_vnops.c
--- a/sys/fs/tmpfs/tmpfs_vnops.c        Mon May 02 22:27:53 2011 +0000
+++ b/sys/fs/tmpfs/tmpfs_vnops.c        Mon May 02 23:42:10 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tmpfs_vnops.c,v 1.77 2011/04/24 21:35:29 rmind Exp $   */
+/*     $NetBSD: tmpfs_vnops.c,v 1.78 2011/05/02 23:42:10 rmind Exp $   */
 
 /*
  * Copyright (c) 2005, 2006, 2007 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: tmpfs_vnops.c,v 1.77 2011/04/24 21:35:29 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: tmpfs_vnops.c,v 1.78 2011/05/02 23:42:10 rmind Exp $");
 
 #include <sys/param.h>
 #include <sys/dirent.h>
@@ -738,7 +738,7 @@
 }
 
 /*
- * tmpfs:link: create hard link.
+ * tmpfs_link: create hard link.
  */
 int
 tmpfs_link(void *v)
@@ -1395,25 +1395,29 @@
        return lf_advlock(v, &node->tn_lockf, node->tn_size);
 }
 
-/* --------------------------------------------------------------------- */
-
 int
 tmpfs_getpages(void *v)
 {
-       struct vnode *vp = ((struct vop_getpages_args *)v)->a_vp;
-       voff_t offset = ((struct vop_getpages_args *)v)->a_offset;
-       struct vm_page **m = ((struct vop_getpages_args *)v)->a_m;
-       int *count = ((struct vop_getpages_args *)v)->a_count;
-       int centeridx = ((struct vop_getpages_args *)v)->a_centeridx;
-       vm_prot_t access_type = ((struct vop_getpages_args *)v)->a_access_type;
-       int advice = ((struct vop_getpages_args *)v)->a_advice;
-       int flags = ((struct vop_getpages_args *)v)->a_flags;
-
-       int error;
-       int i;
+       struct vop_getpages_args /* {
+               struct vnode *a_vp;
+               voff_t a_offset;
+               struct vm_page **a_m;
+               int *a_count;
+               int a_centeridx;
+               vm_prot_t a_access_type;
+               int a_advice;
+               int a_flags;
+       } */ * const ap = v;
+       struct vnode *vp = ap->a_vp;
+       const voff_t offset = ap->a_offset;
+       struct vm_page **pgs = ap->a_m;
+       const int centeridx = ap->a_centeridx;
+       const vm_prot_t access_type = ap->a_access_type;
+       const int advice = ap->a_advice;
+       const int flags = ap->a_flags;
+       int error, npages = *ap->a_count;
        struct tmpfs_node *node;
        struct uvm_object *uobj;
-       int npages = *count;
 
        KASSERT(vp->v_type == VREG);
        KASSERT(mutex_owned(&vp->v_interlock));
@@ -1421,8 +1425,9 @@
        node = VP_TO_TMPFS_NODE(vp);
        uobj = node->tn_spec.tn_reg.tn_aobj;
 
-       /* We currently don't rely on PGO_PASTEOF. */
-
+       /*
+        * Currently, PGO_PASTEOF is not supported.
+        */
        if (vp->v_size <= offset + (centeridx << PAGE_SHIFT)) {
                if ((flags & PGO_LOCKED) == 0)
                        mutex_exit(&vp->v_interlock);
@@ -1447,47 +1452,44 @@
        mutex_exit(&vp->v_interlock);
 
        /*
-        * Make sure that the array on which we will store the
-        * gotten pages is clean.  Otherwise uao_get (pointed to by
-        * the pgo_get below) gets confused and does not return the
-        * appropriate pages.
+        * Invoke the pager.
         *
-        * XXX This shall be revisited when kern/32166 is addressed
-        * because the loop to clean m[i] will most likely be redundant
-        * as well as the PGO_ALLPAGES flag.
+        * Clean the array of pages before.  XXX: PR/32166
+        * Note that vnode lock is shared with underlying UVM object.
         */
-       if (m != NULL)
-               for (i = 0; i < npages; i++)
-                       m[i] = NULL;
+       if (pgs) {
+               memset(pgs, 0, sizeof(struct vm_pages *) * npages);
+       }
        mutex_enter(&uobj->vmobjlock);
-       error = (*uobj->pgops->pgo_get)(uobj, offset, m, &npages, centeridx,
+       error = (*uobj->pgops->pgo_get)(uobj, offset, pgs, &npages, centeridx,
            access_type, advice, flags | PGO_ALLPAGES);
+
 #if defined(DEBUG)
-       {
-               /* Make sure that all the pages we return are valid. */
-               int dbgi;
-               if (error == 0 && m != NULL)
-                       for (dbgi = 0; dbgi < npages; dbgi++)
-                               KASSERT(m[dbgi] != NULL);
+       if (!error && pgs) {
+               for (int i = 0; i < npages; i++) {
+                       KASSERT(pgs[i] != NULL);
+               }
        }
 #endif
-
        return error;
 }
 
-/* --------------------------------------------------------------------- */
-
 int
 tmpfs_putpages(void *v)
 {
-       struct vnode *vp = ((struct vop_putpages_args *)v)->a_vp;
-       voff_t offlo = ((struct vop_putpages_args *)v)->a_offlo;
-       voff_t offhi = ((struct vop_putpages_args *)v)->a_offhi;
-       int flags = ((struct vop_putpages_args *)v)->a_flags;
-
-       int error;
+       struct vop_putpages_args /* {
+               struct vnode *a_vp;
+               voff_t a_offlo;
+               voff_t a_offhi;
+               int a_flags;
+       } */ * const ap = v;
+       struct vnode *vp = ap->a_vp;
+       const voff_t offlo = ap->a_offlo;
+       const voff_t offhi = ap->a_offhi;
+       const int flags = ap->a_flags;
        struct tmpfs_node *node;
        struct uvm_object *uobj;
+       int error;
 
        KASSERT(mutex_owned(&vp->v_interlock));