xref: /illumos-gate/usr/src/uts/common/fs/ctfs/ctfs_latest.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
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 #include <sys/types.h>
27 #include <sys/param.h>
28 #include <sys/time.h>
29 #include <sys/cred.h>
30 #include <sys/vfs.h>
31 #include <sys/vfs_opreg.h>
32 #include <sys/gfs.h>
33 #include <sys/vnode.h>
34 #include <sys/systm.h>
35 #include <sys/errno.h>
36 #include <sys/sysmacros.h>
37 #include <fs/fs_subr.h>
38 #include <sys/contract.h>
39 #include <sys/contract_impl.h>
40 #include <sys/ctfs.h>
41 #include <sys/ctfs_impl.h>
42 #include <sys/file.h>
43 
44 /*
45  * CTFS routines for the /system/contract/<type>/latest vnode.
46  */
47 
48 /*
49  * ctfs_create_latenode
50  */
51 vnode_t *
52 ctfs_create_latenode(vnode_t *pvp)
53 {
54 	return (gfs_file_create(sizeof (ctfs_latenode_t), pvp,
55 	    ctfs_ops_latest));
56 }
57 
58 /*
59  * ctfs_latest_nested_open
60  *
61  * The latest node is just a doorway to the status file; this function
62  * is used by ctfs_latest_access, ctfs_latest_open, and
63  * ctfs_latest_getattr to obtain that file.
64  */
65 static vnode_t *
66 ctfs_latest_nested_open(vnode_t *vp, cred_t *cr)
67 {
68 	contract_t *ct = ttolwp(curthread)->lwp_ct_latest[
69 	    gfs_file_index(gfs_file_parent(vp))];
70 
71 	if (ct) {
72 		vnode_t *cvp, *svp;
73 
74 		cvp = ctfs_create_cdirnode(gfs_file_parent(vp), ct);
75 
76 		gfs_file_set_index(cvp, -1);
77 
78 		VERIFY(gfs_dir_lookup(cvp, "status", &svp,
79 		    cr, 0, NULL, NULL) == 0);
80 
81 		VN_RELE(cvp);
82 
83 		return (svp);
84 	}
85 
86 	return (NULL);
87 }
88 
89 /*
90  * ctfs_latest_access - VOP_ACCESS entry point
91  *
92  * Fails if there isn't a latest contract.
93  */
94 /* ARGSUSED */
95 static int
96 ctfs_latest_access(
97 	vnode_t *vp,
98 	int mode,
99 	int flags,
100 	cred_t *cr,
101 	caller_context_t *ct)
102 {
103 	vnode_t *nvp;
104 
105 	if (mode & (VEXEC | VWRITE))
106 		return (EACCES);
107 
108 	if (nvp = ctfs_latest_nested_open(vp, cr)) {
109 		VN_RELE(nvp);
110 		return (0);
111 	}
112 
113 	return (ESRCH);
114 }
115 
116 /*
117  * ctfs_latest_open - VOP_OPEN entry point
118  *
119  * After checking the mode bits, opens and returns the status file for
120  * the LWP's latest contract.
121  */
122 static int
123 ctfs_latest_open(vnode_t **vpp, int flag, cred_t *cr, caller_context_t *ct)
124 {
125 	vnode_t *nvp;
126 
127 	if (flag != (FREAD | FOFFMAX))
128 		return (EINVAL);
129 
130 	if (nvp = ctfs_latest_nested_open(*vpp, cr)) {
131 		VN_RELE(*vpp);
132 		*vpp = nvp;
133 		return (VOP_OPEN(vpp, flag, cr, ct));
134 	}
135 
136 	return (ESRCH);
137 }
138 
139 /*
140  * ctfs_latest_getattr - the VOP_GETATTR entry point
141  *
142  * Fetches and calls VOP_GETATTR on the status file for the LWP's
143  * latest contract.  Otherwise it fakes up something bland.
144  */
145 static int
146 ctfs_latest_getattr(
147 	vnode_t *vp,
148 	vattr_t *vap,
149 	int flags,
150 	cred_t *cr,
151 	caller_context_t *ct)
152 {
153 	vnode_t *nvp;
154 
155 	if (nvp = ctfs_latest_nested_open(vp, cr)) {
156 		int res = VOP_GETATTR(nvp, vap, flags, cr, ct);
157 		VN_RELE(nvp);
158 		return (res);
159 	}
160 
161 	vap->va_type = VREG;
162 	vap->va_mode = 0444;
163 	vap->va_nlink = 1;
164 	vap->va_size = 0;
165 	vap->va_ctime.tv_sec = vp->v_vfsp->vfs_mtime;
166 	vap->va_ctime.tv_nsec = 0;
167 	vap->va_atime = vap->va_mtime = vap->va_ctime;
168 	ctfs_common_getattr(vp, vap);
169 
170 	return (0);
171 }
172 
173 const fs_operation_def_t ctfs_tops_latest[] = {
174 	{ VOPNAME_OPEN,		{ .vop_open = ctfs_latest_open } },
175 	{ VOPNAME_CLOSE,	{ .error = fs_inval } },
176 	{ VOPNAME_IOCTL,	{ .error = fs_inval } },
177 	{ VOPNAME_GETATTR,	{ .vop_getattr = ctfs_latest_getattr } },
178 	{ VOPNAME_ACCESS,	{ .vop_access = ctfs_latest_access } },
179 	{ VOPNAME_READDIR,	{ .error = fs_notdir } },
180 	{ VOPNAME_LOOKUP,	{ .error = fs_notdir } },
181 	{ VOPNAME_INACTIVE,	{ .vop_inactive = gfs_vop_inactive } },
182 	{ NULL, NULL }
183 };
184