kernel/fs/ctfs/ctfs_sym.c

   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 #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/gfs.h>
  34 #include <sys/vnode.h>
  35 #include <sys/systm.h>
  36 #include <sys/errno.h>
  37 #include <sys/sysmacros.h>
  38 #include <sys/fs_subr.h>
  39 #include <sys/contract.h>
  40 #include <sys/contract_impl.h>
  41 #include <sys/ctfs.h>
  42 #include <sys/ctfs_impl.h>
  43 #include <sys/file.h>
  44 #include <sys/cmn_err.h>
  45
  46 /*
  47  * CTFS routines for the /system/contract/all/<ctid> vnode.
  48  */
  49
  50 /*
  51  * ctfs_create_symnode
  52  *
  53  * Creates and returns a symnode for the specified contract.
  54  */
  55 vnode_t *
  56 ctfs_create_symnode(vnode_t *pvp, contract_t *ct)
  57 {
  58         ctfs_symnode_t *symnode;
  59         vnode_t *vp;
  60         size_t len;
  61
  62         vp = gfs_file_create(sizeof (ctfs_symnode_t), pvp, &ctfs_ops_sym);
  63         vp->v_type = VLNK;
  64         symnode = vp->v_data;
  65
  66         symnode->ctfs_sn_contract = ct;
  67         symnode->ctfs_sn_size = len = snprintf(NULL, 0, "../%s/%ld",
  68             ct->ct_type->ct_type_name, (long)ct->ct_id) + 1;
  69         symnode->ctfs_sn_string = kmem_alloc(len, KM_SLEEP);
  70         VERIFY(snprintf(symnode->ctfs_sn_string, len, "../%s/%ld",
  71             ct->ct_type->ct_type_name, (long)ct->ct_id) < len);
  72
  73         contract_hold(ct);
  74
  75         return (vp);
  76 }
  77
  78 /*
  79  * ctfs_sym_getattr - fop_getattr entry point
  80  */
  81 /* ARGSUSED */
  82 static int
  83 ctfs_sym_getattr(
  84         vnode_t *vp,
  85         vattr_t *vap,
  86         int flags,
  87         cred_t *cr,
  88         caller_context_t *ct)
  89 {
  90         ctfs_symnode_t *symnode = vp->v_data;
  91
  92         vap->va_type = VLNK;
  93         vap->va_mode = 0444;
  94         vap->va_nlink = 1;
  95         vap->va_size = symnode->ctfs_sn_size - 1;
  96         vap->va_mtime = vap->va_atime = vap->va_ctime =
  97             symnode->ctfs_sn_contract->ct_ctime;
  98         ctfs_common_getattr(vp, vap);
  99
 100         return (0);
 101 }
 102
 103 /*
 104  * ctfs_sym_readlink - fop_readlink entry point
 105  *
 106  * Since we built the symlink string in ctfs_create_symnode, this is
 107  * just a uiomove.
 108  */
 109 /* ARGSUSED */
 110 int
 111 ctfs_sym_readlink(vnode_t *vp, uio_t *uiop, cred_t *cr, caller_context_t *ct)
 112 {
 113         ctfs_symnode_t *symnode = vp->v_data;
 114
 115         return (uiomove(symnode->ctfs_sn_string, symnode->ctfs_sn_size - 1,
 116             UIO_READ, uiop));
 117 }
 118
 119 /*
 120  * ctfs_sym_inactive - fop_inactive entry point
 121  */
 122 /* ARGSUSED */
 123 static void
 124 ctfs_sym_inactive(vnode_t *vp, cred_t *cr, caller_context_t *ct)
 125 {
 126         ctfs_symnode_t *symnode;
 127
 128         if ((symnode = gfs_file_inactive(vp)) != NULL) {
 129                 contract_rele(symnode->ctfs_sn_contract);
 130                 kmem_free(symnode->ctfs_sn_string, symnode->ctfs_sn_size);
 131                 kmem_free(symnode, sizeof (ctfs_symnode_t));
 132         }
 133 }
 134
 135 const struct vnodeops ctfs_ops_sym = {
 136         .vnop_name = "ctfs all symlink",
 137         .vop_open = ctfs_open,
 138         .vop_close = ctfs_close,
 139         .vop_ioctl = fs_inval,
 140         .vop_getattr = ctfs_sym_getattr,
 141         .vop_readlink = ctfs_sym_readlink,
 142         .vop_access = ctfs_access_readonly,
 143         .vop_readdir = fs_notdir,
 144         .vop_lookup = fs_notdir,
 145         .vop_inactive = ctfs_sym_inactive,
 146 };