xref: /illumos-gate/usr/src/uts/common/fs/ctfs/ctfs_sym.c (revision 9164a50bf932130cbb5097a16f6986873ce0e6e5)
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 2007 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 #include <sys/cmn_err.h>
44 
45 /*
46  * CTFS routines for the /system/contract/all/<ctid> vnode.
47  */
48 
49 /*
50  * ctfs_create_symnode
51  *
52  * Creates and returns a symnode for the specified contract.
53  */
54 vnode_t *
55 ctfs_create_symnode(vnode_t *pvp, contract_t *ct)
56 {
57 	ctfs_symnode_t *symnode;
58 	vnode_t *vp;
59 	size_t len;
60 
61 	vp = gfs_file_create(sizeof (ctfs_symnode_t), pvp, ctfs_ops_sym);
62 	vp->v_type = VLNK;
63 	symnode = vp->v_data;
64 
65 	symnode->ctfs_sn_contract = ct;
66 	symnode->ctfs_sn_size = len = snprintf(NULL, 0, "../%s/%ld",
67 	    ct->ct_type->ct_type_name, (long)ct->ct_id) + 1;
68 	symnode->ctfs_sn_string = kmem_alloc(len, KM_SLEEP);
69 	VERIFY(snprintf(symnode->ctfs_sn_string, len, "../%s/%ld",
70 	    ct->ct_type->ct_type_name, (long)ct->ct_id) < len);
71 
72 	contract_hold(ct);
73 
74 	return (vp);
75 }
76 
77 /*
78  * ctfs_sym_getattr - VOP_GETATTR entry point
79  */
80 /* ARGSUSED */
81 static int
82 ctfs_sym_getattr(
83 	vnode_t *vp,
84 	vattr_t *vap,
85 	int flags,
86 	cred_t *cr,
87 	caller_context_t *ct)
88 {
89 	ctfs_symnode_t *symnode = vp->v_data;
90 
91 	vap->va_type = VLNK;
92 	vap->va_mode = 0444;
93 	vap->va_nlink = 1;
94 	vap->va_size = symnode->ctfs_sn_size - 1;
95 	vap->va_mtime = vap->va_atime = vap->va_ctime =
96 	    symnode->ctfs_sn_contract->ct_ctime;
97 	ctfs_common_getattr(vp, vap);
98 
99 	return (0);
100 }
101 
102 /*
103  * ctfs_sym_readlink - VOP_READLINK entry point
104  *
105  * Since we built the symlink string in ctfs_create_symnode, this is
106  * just a uiomove.
107  */
108 /* ARGSUSED */
109 int
110 ctfs_sym_readlink(vnode_t *vp, uio_t *uiop, cred_t *cr, caller_context_t *ct)
111 {
112 	ctfs_symnode_t *symnode = vp->v_data;
113 
114 	return (uiomove(symnode->ctfs_sn_string, symnode->ctfs_sn_size - 1,
115 	    UIO_READ, uiop));
116 }
117 
118 /*
119  * ctfs_sym_inactive - VOP_INACTIVE entry point
120  */
121 /* ARGSUSED */
122 static void
123 ctfs_sym_inactive(vnode_t *vp, cred_t *cr, caller_context_t *ct)
124 {
125 	ctfs_symnode_t *symnode;
126 
127 	if ((symnode = gfs_file_inactive(vp)) != NULL) {
128 		contract_rele(symnode->ctfs_sn_contract);
129 		kmem_free(symnode->ctfs_sn_string, symnode->ctfs_sn_size);
130 		kmem_free(symnode, sizeof (ctfs_symnode_t));
131 	}
132 }
133 
134 const fs_operation_def_t ctfs_tops_sym[] = {
135 	{ VOPNAME_OPEN,		{ .vop_open = ctfs_open } },
136 	{ VOPNAME_CLOSE,	{ .vop_close = ctfs_close } },
137 	{ VOPNAME_IOCTL,	{ .error = fs_inval } },
138 	{ VOPNAME_GETATTR,	{ .vop_getattr = ctfs_sym_getattr } },
139 	{ VOPNAME_READLINK,	{ .vop_readlink = ctfs_sym_readlink } },
140 	{ VOPNAME_ACCESS,	{ .vop_access = ctfs_access_readonly } },
141 	{ VOPNAME_READDIR,	{ .error = fs_notdir } },
142 	{ VOPNAME_LOOKUP,	{ .error = fs_notdir } },
143 	{ VOPNAME_INACTIVE,	{ .vop_inactive = ctfs_sym_inactive } },
144 	{ NULL, NULL }
145 };
146