/* ARGSUSED */
static int
zfsctl_shares_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
    int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
    int *direntflags, pathname_t *realpnp)
{
	zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
	znode_t *dzp;
	int error;

	ZFS_ENTER(zfsvfs);

	if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
		ZFS_EXIT(zfsvfs);
		return (0);
	}

	if (zfsvfs->z_shares_dir == 0) {
		ZFS_EXIT(zfsvfs);
		return (ENOTSUP);
	}
	if ((error = zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp)) == 0)
		error = VOP_LOOKUP(ZTOV(dzp), nm, vpp, pnp,
		    flags, rdir, cr, ct, direntflags, realpnp);

	VN_RELE(ZTOV(dzp));
	ZFS_EXIT(zfsvfs);

	return (error);
}
/* ARGSUSED */
static int
zfsctl_snapdir_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
    int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
    int *direntflags, pathname_t *realpnp)
{
	zfsctl_snapdir_t *sdp = dvp->v_data;
	objset_t *snap;
	char snapname[MAXNAMELEN];
	char real[MAXNAMELEN];
	char *mountpoint;
	zfs_snapentry_t *sep, search;
	struct mounta margs;
	vfs_t *vfsp;
	size_t mountpoint_len;
	avl_index_t where;
	zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
	int err;

	/*
	 * No extended attributes allowed under .zfs
	 */
	if (flags & LOOKUP_XATTR)
		return (EINVAL);

	ASSERT(dvp->v_type == VDIR);

	/*
	 * If we get a recursive call, that means we got called
	 * from the domount() code while it was trying to look up the
	 * spec (which looks like a local path for zfs).  We need to
	 * add some flag to domount() to tell it not to do this lookup.
	 */
	if (MUTEX_HELD(&sdp->sd_lock))
		return (ENOENT);

	ZFS_ENTER(zfsvfs);

	if (gfs_lookup_dot(vpp, dvp, zfsvfs->z_ctldir, nm) == 0) {
		ZFS_EXIT(zfsvfs);
		return (0);
	}

	if (flags & FIGNORECASE) {
		boolean_t conflict = B_FALSE;

		err = dmu_snapshot_realname(zfsvfs->z_os, nm, real,
		    MAXNAMELEN, &conflict);
		if (err == 0) {
			nm = real;
		} else if (err != ENOTSUP) {
			ZFS_EXIT(zfsvfs);
			return (err);
		}
		if (realpnp)
			(void) strlcpy(realpnp->pn_buf, nm,
			    realpnp->pn_bufsize);
		if (conflict && direntflags)
			*direntflags = ED_CASE_CONFLICT;
	}

	mutex_enter(&sdp->sd_lock);
	search.se_name = (char *)nm;
	if ((sep = avl_find(&sdp->sd_snaps, &search, &where)) != NULL) {
		*vpp = sep->se_root;
		VN_HOLD(*vpp);
		err = traverse(vpp);
		if (err) {
			VN_RELE(*vpp);
			*vpp = NULL;
		} else if (*vpp == sep->se_root) {
			/*
			 * The snapshot was unmounted behind our backs,
			 * try to remount it.
			 */
			goto domount;
		} else {
			/*
			 * VROOT was set during the traverse call.  We need
			 * to clear it since we're pretending to be part
			 * of our parent's vfs.
			 */
			(*vpp)->v_flag &= ~VROOT;
		}
		mutex_exit(&sdp->sd_lock);
		ZFS_EXIT(zfsvfs);
		return (err);
	}

	/*
	 * The requested snapshot is not currently mounted, look it up.
	 */
	err = zfsctl_snapshot_zname(dvp, nm, MAXNAMELEN, snapname);
	if (err) {
		mutex_exit(&sdp->sd_lock);
		ZFS_EXIT(zfsvfs);
		/*
		 * handle "ls *" or "?" in a graceful manner,
		 * forcing EILSEQ to ENOENT.
		 * Since shell ultimately passes "*" or "?" as name to lookup
		 */
		return (err == EILSEQ ? ENOENT : err);
	}
	if (dmu_objset_hold(snapname, FTAG, &snap) != 0) {
		mutex_exit(&sdp->sd_lock);
		ZFS_EXIT(zfsvfs);
		return (ENOENT);
	}

	sep = kmem_alloc(sizeof (zfs_snapentry_t), KM_SLEEP);
	sep->se_name = kmem_alloc(strlen(nm) + 1, KM_SLEEP);
	(void) strcpy(sep->se_name, nm);
	*vpp = sep->se_root = zfsctl_snapshot_mknode(dvp, dmu_objset_id(snap));
	avl_insert(&sdp->sd_snaps, sep, where);

	dmu_objset_rele(snap, FTAG);
domount:
	mountpoint_len = strlen(refstr_value(dvp->v_vfsp->vfs_mntpt)) +
	    strlen("/.zfs/snapshot/") + strlen(nm) + 1;
	mountpoint = kmem_alloc(mountpoint_len, KM_SLEEP);
	(void) snprintf(mountpoint, mountpoint_len, "%s/.zfs/snapshot/%s",
	    refstr_value(dvp->v_vfsp->vfs_mntpt), nm);

	margs.spec = snapname;
	margs.dir = mountpoint;
	margs.flags = MS_SYSSPACE | MS_NOMNTTAB;
	margs.fstype = "zfs";
	margs.dataptr = NULL;
	margs.datalen = 0;
	margs.optptr = NULL;
	margs.optlen = 0;

	err = domount("zfs", &margs, *vpp, kcred, &vfsp);
	kmem_free(mountpoint, mountpoint_len);

	if (err == 0) {
		/*
		 * Return the mounted root rather than the covered mount point.
		 * Takes the GFS vnode at .zfs/snapshot/<snapname> and returns
		 * the ZFS vnode mounted on top of the GFS node.  This ZFS
		 * vnode is the root of the newly created vfsp.
		 */
		VFS_RELE(vfsp);
		err = traverse(vpp);
	}

	if (err == 0) {
		/*
		 * Fix up the root vnode mounted on .zfs/snapshot/<snapname>.
		 *
		 * This is where we lie about our v_vfsp in order to
		 * make .zfs/snapshot/<snapname> accessible over NFS
		 * without requiring manual mounts of <snapname>.
		 */
		ASSERT(VTOZ(*vpp)->z_zfsvfs != zfsvfs);
		VTOZ(*vpp)->z_zfsvfs->z_parent = zfsvfs;
		(*vpp)->v_vfsp = zfsvfs->z_vfs;
		(*vpp)->v_flag &= ~VROOT;
	}
	mutex_exit(&sdp->sd_lock);
	ZFS_EXIT(zfsvfs);

	/*
	 * If we had an error, drop our hold on the vnode and
	 * zfsctl_snapshot_inactive() will clean up.
	 */
	if (err) {
		VN_RELE(*vpp);
		*vpp = NULL;
	}
	return (err);
}
Example #3
0
File: gfs.c Project: RJVB/zfs
/*
 * gfs_dir_lookup()
 *
 * Looks up the given name in the directory and returns the corresponding
 * vnode, if found.
 *
 * First, we search statically defined entries, if any, with a call to
 * gfs_dir_lookup_static().  If no static entry is found, and we have
 * a callback function we try a dynamic lookup via gfs_dir_lookup_dynamic().
 *
 * This function returns 0 on success, non-zero on error.
 */
int
gfs_dir_lookup(struct vnode *dvp, const char *nm, struct vnode **vpp, cred_t *cr,
    int flags, int *direntflags, pathname_t *realpnp)
{
	gfs_dir_t *dp = vnode_fsnode(dvp);
	boolean_t casecheck;
	struct vnode *dynvp = NULL;
	struct vnode *vp = NULL;
	int (*compare)(const char *, const char *);
	int error, idx;

    dprintf("gfs_dir_lookup\n");

	ASSERT(dvp->v_type == VDIR);

	if (gfs_lookup_dot(vpp, dvp, dp->gfsd_file.gfs_parent, nm) == 0)
		return (0);

	casecheck = (flags & FIGNORECASE) != 0 && direntflags != NULL;
#if 1 //FIXME
	if (/*vfs_has_feature(vnode_mount(dvp), VFSFT_NOCASESENSITIVE) ||*/
	    (flags & FIGNORECASE))
		compare = strcasecmp;
	else
#endif
		compare = strcmp;

	gfs_dir_lock(dp);

	error = gfs_dir_lookup_static(compare, dp, nm, dvp, &idx, &vp, realpnp);

	if (vp && casecheck) {
		gfs_dirent_t *ge;
		int i;

		for (i = idx + 1; i < dp->gfsd_nstatic; i++) {
			ge = &dp->gfsd_static[i];

			if (strcasecmp(ge->gfse_name, nm) == 0) {
				*direntflags |= ED_CASE_CONFLICT;
				goto out;
			}
		}
	}
#if 0
	if ((error || casecheck) && dp->gfsd_lookup)
		error = gfs_dir_lookup_dynamic(dp->gfsd_lookup, dp, nm, dvp,
		    &dynvp, cr, flags, direntflags, vp ? NULL : realpnp);
#endif

	if (vp && dynvp) {
		/* static and dynamic entries are case-insensitive conflict */
		ASSERT(casecheck);
		*direntflags |= ED_CASE_CONFLICT;
		VN_RELE(dynvp);
	} else if (vp == NULL) {
		vp = dynvp;
	} else if (error == ENOENT) {
		error = 0;
	} else if (error) {
		VN_RELE(vp);
		vp = NULL;
	}

out:
	gfs_dir_unlock(dp);

	*vpp = vp;
	return (error);
}