[src/trunk]: src/sys/ufs/ffs Change snapshot_expunge() to use vfs_vnode_itera...

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

details:   https://anonhg.NetBSD.org/src/rev/73cbee815590
branches:  trunk
changeset: 327799:73cbee815590
user:      hannken <hannken%NetBSD.org@localhost>
date:      Mon Mar 17 09:29:20 2014 +0000

description:
Change snapshot_expunge() to use vfs_vnode_iterator.

diffstat:

 sys/ufs/ffs/ffs_snapshot.c |  56 +++++++++++++--------------------------------
 1 files changed, 17 insertions(+), 39 deletions(-)

diffs (126 lines):

diff -r 23088084d92b -r 73cbee815590 sys/ufs/ffs/ffs_snapshot.c
--- a/sys/ufs/ffs/ffs_snapshot.c        Mon Mar 17 09:28:37 2014 +0000
+++ b/sys/ufs/ffs/ffs_snapshot.c        Mon Mar 17 09:29:20 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ffs_snapshot.c,v 1.132 2013/12/17 01:17:39 joerg Exp $ */
+/*     $NetBSD: ffs_snapshot.c,v 1.133 2014/03/17 09:29:20 hannken Exp $       */
 
 /*
  * Copyright 2000 Marshall Kirk McKusick. All Rights Reserved.
@@ -38,7 +38,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ffs_snapshot.c,v 1.132 2013/12/17 01:17:39 joerg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ffs_snapshot.c,v 1.133 2014/03/17 09:29:20 hannken Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_ffs.h"
@@ -617,7 +617,8 @@
        struct inode *xp;
        struct lwp *l = curlwp;
        struct vattr vat;
-       struct vnode *logvp = NULL, *mvp = NULL, *xvp;
+       struct vnode *logvp = NULL, *xvp;
+       struct vnode_iterator *marker;
 
        *snaplist = NULL;
        /*
@@ -631,41 +632,18 @@
                        goto out;
        }
        /*
-        * Allocate a marker vnode.
-        */
-       mvp = vnalloc(mp);
-       /*
         * We also calculate the needed size for the snapshot list.
         */
        *snaplistsize = fs->fs_ncg + howmany(fs->fs_cssize, fs->fs_bsize) +
            FSMAXSNAP + 1 /* superblock */ + 1 /* last block */ + 1 /* size */;
-       mutex_enter(&mntvnode_lock);
-       /*
-        * NOTE: not using the TAILQ_FOREACH here since in this loop vgone()
-        * and vclean() can be called indirectly
-        */
-       for (xvp = TAILQ_FIRST(&mp->mnt_vnodelist); xvp; xvp = vunmark(mvp)) {
-               vmark(mvp, xvp);
-               /*
-                * Make sure this vnode wasn't reclaimed in getnewvnode().
-                * Start over if it has (it won't be on the list anymore).
-                */
-               if (xvp->v_mount != mp || vismarker(xvp))
-                       continue;
-               mutex_enter(xvp->v_interlock);
-               if ((xvp->v_iflag & VI_XLOCK) ||
-                   xvp->v_usecount == 0 || xvp->v_type == VNON ||
-                   VTOI(xvp) == NULL ||
+
+       vfs_vnode_iterator_init(mp, &marker);
+       while (vfs_vnode_iterator_next(marker, &xvp)) {
+               if (xvp->v_type == VNON || VTOI(xvp) == NULL ||
                    (VTOI(xvp)->i_flags & SF_SNAPSHOT)) {
-                       mutex_exit(xvp->v_interlock);
+                       vrele(xvp);
                        continue;
                }
-               mutex_exit(&mntvnode_lock);
-               /*
-                * XXXAD should increase vnode ref count to prevent it
-                * disappearing or being recycled.
-                */
-               mutex_exit(xvp->v_interlock);
 #ifdef DEBUG
                if (snapdebug)
                        vprint("ffs_snapshot: busy vnode", xvp);
@@ -674,11 +652,11 @@
                if (xvp != logvp) {
                        if (VOP_GETATTR(xvp, &vat, l->l_cred) == 0 &&
                            vat.va_nlink > 0) {
-                               mutex_enter(&mntvnode_lock);
+                               vrele(xvp);
                                continue;
                        }
                        if (ffs_checkfreefile(copy_fs, vp, xp->i_number)) {
-                               mutex_enter(&mntvnode_lock);
+                               vrele(xvp);
                                continue;
                        }
                }
@@ -692,7 +670,8 @@
                        if (len > 0 && len < fs->fs_bsize) {
                                error = UFS_WAPBL_BEGIN(mp);
                                if (error) {
-                                       (void)vunmark(mvp);
+                                       vrele(xvp);
+                                       vfs_vnode_iterator_destroy(marker);
                                        goto out;
                                }
                                ffs_blkfree_snap(copy_fs, vp, db_get(xp, loc),
@@ -714,13 +693,14 @@
                                UFS_WAPBL_END(mp);
                        }
                }
+               vrele(xvp);
                if (error) {
-                       (void)vunmark(mvp);
+                       vfs_vnode_iterator_destroy(marker);
                        goto out;
                }
-               mutex_enter(&mntvnode_lock);
        }
-       mutex_exit(&mntvnode_lock);
+       vfs_vnode_iterator_destroy(marker);
+
        /*
         * Create a preliminary list of preallocated snapshot blocks.
         */
@@ -741,8 +721,6 @@
        (*snaplist)[0] = blkp - &(*snaplist)[0];
 
 out:
-       if (mvp != NULL)
-               vnfree(mvp);
        if (logvp != NULL)
                vput(logvp);
        if (error && *snaplist != NULL) {