[src/trunk]: src/sys/compat/ultrix Switch ultrix_sys_getmnt() to mountlist it...

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

details:   https://anonhg.NetBSD.org/src/rev/fc25eb41a7d7
branches:  trunk
changeset: 823122:fc25eb41a7d7
user:      hannken <hannken%NetBSD.org@localhost>
date:      Thu Apr 13 09:18:18 2017 +0000

description:
Switch ultrix_sys_getmnt() to mountlist iterator.
Really skip "start" items instead of a useless loop.
Compile tested only.

diffstat:

 sys/compat/ultrix/ultrix_fs.c |  29 +++++++++++------------------
 1 files changed, 11 insertions(+), 18 deletions(-)

diffs (97 lines):

diff -r bb90a1c2b9f8 -r fc25eb41a7d7 sys/compat/ultrix/ultrix_fs.c
--- a/sys/compat/ultrix/ultrix_fs.c     Thu Apr 13 09:17:55 2017 +0000
+++ b/sys/compat/ultrix/ultrix_fs.c     Thu Apr 13 09:18:18 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ultrix_fs.c,v 1.56 2015/10/23 19:40:11 maxv Exp $      */
+/*     $NetBSD: ultrix_fs.c,v 1.57 2017/04/13 09:18:18 hannken Exp $   */
 
 /*
  * Copyright (c) 1995, 1997 Jonathan Stone
@@ -33,7 +33,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ultrix_fs.c,v 1.56 2015/10/23 19:40:11 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ultrix_fs.c,v 1.57 2017/04/13 09:18:18 hannken Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -206,9 +206,10 @@
 int
 ultrix_sys_getmnt(struct lwp *l, const struct ultrix_sys_getmnt_args *uap, register_t *retval)
 {
-       struct mount *mp, *nmp;
+       struct mount *mp;
        struct statvfs *sp;
        struct ultrix_fs_data *sfsp;
+       mount_iterator_t *iter;
        char *path;
        int mntflags;
        int skip;
@@ -216,7 +217,6 @@
        long count, maxcount;
        int error;
 
-       nmp = NULL;     /* XXX keep gcc quiet */
        path = NULL;
        error = 0;
        maxcount = SCARG(uap, bufsize) / sizeof(struct ultrix_fs_data);
@@ -237,6 +237,7 @@
                if ((error = copyinstr(SCARG(uap, path), path,
                                       MAXPATHLEN, NULL)) != 0)
                        goto bad;
+               skip = 0;
                maxcount = 1;
        } else {
                /*
@@ -247,20 +248,14 @@
                if ((error = copyin((void *)SCARG(uap, start), &start,
                                    sizeof(*SCARG(uap, start))))  != 0)
                        goto bad;
-               mutex_enter(&mountlist_lock);
-               for (skip = start, mp = TAILQ_FIRST(&mountlist);
-                   mp != NULL && skip-- > 0;
-                   mp = TAILQ_NEXT(mp, mnt_list))
-                       continue;
-               mutex_exit(&mountlist_lock);
+               skip = start;
        }
 
-       mutex_enter(&mountlist_lock);
-       for (count = 0, mp = TAILQ_FIRST(&mountlist);
-           mp != NULL && count < maxcount; mp = nmp) {
-               if (vfs_busy(mp, &nmp)) {
+       count = 0;
+       mountlist_iterator_init(&iter);
+       while (count < maxcount && (mp = mountlist_iterator_next(iter))) {
+               if (skip-- > 0)
                        continue;
-               }
                if (sfsp != NULL) {
                        struct ultrix_fs_data tem;
                        sp = &mp->mnt_stat;
@@ -281,16 +276,13 @@
                                make_ultrix_mntent(sp, &tem);
                                if ((error = copyout((void *)&tem, sfsp,
                                    sizeof(tem))) != 0) {
-                                       vfs_unbusy(mp, false, NULL);
                                        goto bad;
                                }
                                sfsp++;
                                count++;
                        }
                }
-               vfs_unbusy(mp, false, &nmp);
        }
-       mutex_exit(&mountlist_lock);
 
        if (sfsp != NULL && count > maxcount)
                *retval = maxcount;
@@ -298,6 +290,7 @@
                *retval = count;
 
 bad:
+       mountlist_iterator_destroy(iter);
        if (path)
                free(path, M_TEMP);
        return error;