xref: /titanic_41/usr/src/uts/common/fs/ctfs/ctfs_latest.c (revision fcf3ce441efd61da9bb2884968af01cb7c1452cc)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <sys/types.h>
29 #include <sys/param.h>
30 #include <sys/time.h>
31 #include <sys/cred.h>
32 #include <sys/vfs.h>
33 #include <sys/vfs_opreg.h>
34 #include <sys/gfs.h>
35 #include <sys/vnode.h>
36 #include <sys/systm.h>
37 #include <sys/errno.h>
38 #include <sys/sysmacros.h>
39 #include <fs/fs_subr.h>
40 #include <sys/contract.h>
41 #include <sys/contract_impl.h>
42 #include <sys/ctfs.h>
43 #include <sys/ctfs_impl.h>
44 #include <sys/file.h>
45 
46 /*
47  * CTFS routines for the /system/contract/<type>/latest vnode.
48  */
49 
50 /*
51  * ctfs_create_latenode
52  */
53 vnode_t *
54 ctfs_create_latenode(vnode_t *pvp)
55 {
56 	return (gfs_file_create(sizeof (ctfs_latenode_t), pvp,
57 	    ctfs_ops_latest));
58 }
59 
60 /*
61  * ctfs_latest_nested_open
62  *
63  * The latest node is just a doorway to the status file; this function
64  * is used by ctfs_latest_access, ctfs_latest_open, and
65  * ctfs_latest_getattr to obtain that file.
66  */
67 static vnode_t *
68 ctfs_latest_nested_open(vnode_t *vp, cred_t *cr)
69 {
70 	contract_t *ct = ttolwp(curthread)->lwp_ct_latest[
71 	    gfs_file_index(gfs_file_parent(vp))];
72 
73 	if (ct) {
74 		vnode_t *cvp, *svp;
75 
76 		cvp = ctfs_create_cdirnode(gfs_file_parent(vp), ct);
77 
78 		gfs_file_set_index(cvp, -1);
79 
80 		VERIFY(gfs_dir_lookup(cvp, "status", &svp,
81 		    cr, 0, NULL, NULL) == 0);
82 
83 		VN_RELE(cvp);
84 
85 		return (svp);
86 	}
87 
88 	return (NULL);
89 }
90 
91 /*
92  * ctfs_latest_access - VOP_ACCESS entry point
93  *
94  * Fails if there isn't a latest contract.
95  */
96 /* ARGSUSED */
97 static int
98 ctfs_latest_access(
99 	vnode_t *vp,
100 	int mode,
101 	int flags,
102 	cred_t *cr,
103 	caller_context_t *ct)
104 {
105 	vnode_t *nvp;
106 
107 	if (mode & (VEXEC | VWRITE))
108 		return (EACCES);
109 
110 	if (nvp = ctfs_latest_nested_open(vp, cr)) {
111 		VN_RELE(nvp);
112 		return (0);
113 	}
114 
115 	return (ESRCH);
116 }
117 
118 /*
119  * ctfs_latest_open - VOP_OPEN entry point
120  *
121  * After checking the mode bits, opens and returns the status file for
122  * the LWP's latest contract.
123  */
124 static int
125 ctfs_latest_open(vnode_t **vpp, int flag, cred_t *cr, caller_context_t *ct)
126 {
127 	vnode_t *nvp;
128 
129 	if (flag != (FREAD | FOFFMAX))
130 		return (EINVAL);
131 
132 	if (nvp = ctfs_latest_nested_open(*vpp, cr)) {
133 		VN_RELE(*vpp);
134 		*vpp = nvp;
135 		return (VOP_OPEN(vpp, flag, cr, ct));
136 	}
137 
138 	return (ESRCH);
139 }
140 
141 /*
142  * ctfs_latest_getattr - the VOP_GETATTR entry point
143  *
144  * Fetches and calls VOP_GETATTR on the status file for the LWP's
145  * latest contract.  Otherwise it fakes up something bland.
146  */
147 static int
148 ctfs_latest_getattr(
149 	vnode_t *vp,
150 	vattr_t *vap,
151 	int flags,
152 	cred_t *cr,
153 	caller_context_t *ct)
154 {
155 	vnode_t *nvp;
156 
157 	if (nvp = ctfs_latest_nested_open(vp, cr)) {
158 		int res = VOP_GETATTR(nvp, vap, flags, cr, ct);
159 		VN_RELE(nvp);
160 		return (res);
161 	}
162 
163 	vap->va_type = VREG;
164 	vap->va_mode = 0444;
165 	vap->va_nlink = 1;
166 	vap->va_size = 0;
167 	vap->va_ctime.tv_sec = vp->v_vfsp->vfs_mtime;
168 	vap->va_ctime.tv_nsec = 0;
169 	vap->va_atime = vap->va_mtime = vap->va_ctime;
170 	ctfs_common_getattr(vp, vap);
171 
172 	return (0);
173 }
174 
175 const fs_operation_def_t ctfs_tops_latest[] = {
176 	{ VOPNAME_OPEN,		{ .vop_open = ctfs_latest_open } },
177 	{ VOPNAME_CLOSE,	{ .error = fs_inval } },
178 	{ VOPNAME_IOCTL,	{ .error = fs_inval } },
179 	{ VOPNAME_GETATTR,	{ .vop_getattr = ctfs_latest_getattr } },
180 	{ VOPNAME_ACCESS,	{ .vop_access = ctfs_latest_access } },
181 	{ VOPNAME_READDIR,	{ .error = fs_notdir } },
182 	{ VOPNAME_LOOKUP,	{ .error = fs_notdir } },
183 	{ VOPNAME_INACTIVE,	{ .vop_inactive = gfs_vop_inactive } },
184 	{ NULL, NULL }
185 };
186