[src/trunk]: src/sys/rump/librump/rumpvfs support dotdot lookups

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

details:   https://anonhg.NetBSD.org/src/rev/77da6ce35806
branches:  trunk
changeset: 756347:77da6ce35806
user:      pooka <pooka%NetBSD.org@localhost>
date:      Tue Jul 13 18:08:58 2010 +0000

description:
support dotdot lookups

diffstat:

 sys/rump/librump/rumpvfs/rumpfs.c |  51 +++++++++++++++++++++++++-------------
 1 files changed, 33 insertions(+), 18 deletions(-)

diffs (139 lines):

diff -r d0a32b30a97e -r 77da6ce35806 sys/rump/librump/rumpvfs/rumpfs.c
--- a/sys/rump/librump/rumpvfs/rumpfs.c Tue Jul 13 17:49:24 2010 +0000
+++ b/sys/rump/librump/rumpvfs/rumpfs.c Tue Jul 13 18:08:58 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rumpfs.c,v 1.61 2010/07/09 08:10:50 hannken Exp $      */
+/*     $NetBSD: rumpfs.c,v 1.62 2010/07/13 18:08:58 pooka Exp $        */
 
 /*
  * Copyright (c) 2009  Antti Kantee.  All Rights Reserved.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rumpfs.c,v 1.61 2010/07/09 08:10:50 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rumpfs.c,v 1.62 2010/07/13 18:08:58 pooka Exp $");
 
 #include <sys/param.h>
 #include <sys/atomic.h>
@@ -149,6 +149,7 @@
                } reg;
                struct {                /* VDIR */
                        LIST_HEAD(, rumpfs_dent) dents;
+                       struct rumpfs_node *parent;
                        int flags;
                } dir;
                struct {
@@ -161,6 +162,7 @@
 #define rn_writefd     rn_u.reg.writefd
 #define rn_offset      rn_u.reg.offset
 #define rn_dir         rn_u.dir.dents
+#define rn_parent      rn_u.dir.parent
 #define rn_linktarg    rn_u.link.target
 #define rn_linklen     rn_u.link.len
 
@@ -579,13 +581,8 @@
        struct rumpfs_node *rnd = dvp->v_data, *rn;
        struct rumpfs_dent *rd = NULL;
        struct etfs *et;
-       int rv;
-
-       /* we handle only some "non-special" cases */
-       if (!(((cnp->cn_flags & ISLASTCN) == 0) || (cnp->cn_nameiop != RENAME)))
-               return EOPNOTSUPP;
-       if (!((cnp->cn_flags & ISDOTDOT) == 0))
-               return EOPNOTSUPP;
+       bool dotdot = (cnp->cn_flags & ISDOTDOT) != 0;
+       int rv = 0;
 
        /* check for dot, return directly if the case */
        if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
@@ -594,6 +591,10 @@
                return 0;
        }
 
+       /* we handle only some "non-special" cases */
+       if (!(((cnp->cn_flags & ISLASTCN) == 0) || (cnp->cn_nameiop != RENAME)))
+               return EOPNOTSUPP;
+
        /* check for etfs */
        if (dvp == rootvnode && cnp->cn_nameiop == LOOKUP) {
                bool found;
@@ -622,6 +623,9 @@
                size_t newpathlen;
                int hft, error;
 
+               if (dotdot)
+                       return EOPNOTSUPP;
+
                newpathlen = strlen(rnd->rn_hostpath) + 1 + cnp->cn_namelen + 1;
                newpath = malloc(newpathlen, M_TEMP, M_WAITOK);
 
@@ -649,11 +653,16 @@
 
                goto getvnode;
        } else {
-               LIST_FOREACH(rd, &rnd->rn_dir, rd_entries) {
-                       if (rd->rd_namelen == cnp->cn_namelen &&
-                           strncmp(rd->rd_name, cnp->cn_nameptr,
-                             cnp->cn_namelen) == 0)
-                               break;
+               if (dotdot) {
+                       rn = rnd->rn_parent;
+                       goto getvnode;
+               } else {
+                       LIST_FOREACH(rd, &rnd->rn_dir, rd_entries) {
+                               if (rd->rd_namelen == cnp->cn_namelen &&
+                                   strncmp(rd->rd_name, cnp->cn_nameptr,
+                                     cnp->cn_namelen) == 0)
+                                       break;
+                       }
                }
        }
 
@@ -671,21 +680,25 @@
 
  getvnode:
        KASSERT(rn);
+       if (dotdot)
+               VOP_UNLOCK(dvp);
        mutex_enter(&reclock);
        if ((vp = rn->rn_vp)) {
                mutex_enter(&vp->v_interlock);
                mutex_exit(&reclock);
-               if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK))
+               if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) {
+                       vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
                        goto getvnode;
+               }
                *vpp = vp;
        } else {
                mutex_exit(&reclock);
                rv = makevnode(dvp->v_mount, rn, vpp);
-               if (rv)
-                       return rv;
        }
+       if (dotdot)
+               vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
 
-       return 0;
+       return rv;
 }
 
 static int
@@ -718,6 +731,7 @@
        int rv = 0;
 
        rn = makeprivate(VDIR, NODEV, DEV_BSIZE);
+       rn->rn_parent = rnd;
        rv = makevnode(dvp->v_mount, rn, vpp);
        if (rv)
                goto out;
@@ -1254,6 +1268,7 @@
        rfsmp = kmem_alloc(sizeof(*rfsmp), KM_SLEEP);
 
        rn = makeprivate(VDIR, NODEV, DEV_BSIZE);
+       rn->rn_parent = rn;
        error = makevnode(mp, rn, &rfsmp->rfsmp_rvp);
        if (error)
                panic("could not create root vnode: %d", error);