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 (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. 23 */ 24 25 #include <sys/vfs.h> 26 #include <smbsrv/smb_ktypes.h> 27 #include <smbsrv/smb_kproto.h> 28 29 static smb_vfs_t *smb_vfs_find(smb_export_t *, vfs_t *); 30 static void smb_vfs_destroy(smb_export_t *, smb_vfs_t *); 31 32 /* 33 * If a hold on the specified VFS has already been taken 34 * then only increment the reference count of the corresponding 35 * smb_vfs_t structure. If no smb_vfs_t structure has been created 36 * yet for the specified VFS then create one and take a hold on 37 * the VFS. 38 */ 39 int 40 smb_vfs_hold(smb_export_t *se, vfs_t *vfsp) 41 { 42 smb_vfs_t *smb_vfs; 43 vnode_t *rootvp; 44 int rc; 45 46 if (se == NULL || vfsp == NULL) 47 return (EINVAL); 48 49 smb_llist_enter(&se->e_vfs_list, RW_WRITER); 50 51 if ((smb_vfs = smb_vfs_find(se, vfsp)) != NULL) { 52 smb_vfs->sv_refcnt++; 53 DTRACE_PROBE1(smb_vfs_hold_hit, smb_vfs_t *, smb_vfs); 54 smb_llist_exit(&se->e_vfs_list); 55 return (0); 56 } 57 58 if ((rc = VFS_ROOT(vfsp, &rootvp)) != 0) { 59 smb_llist_exit(&se->e_vfs_list); 60 return (rc); 61 } 62 63 smb_vfs = kmem_cache_alloc(se->e_cache_vfs, KM_SLEEP); 64 65 bzero(smb_vfs, sizeof (smb_vfs_t)); 66 67 smb_vfs->sv_magic = SMB_VFS_MAGIC; 68 smb_vfs->sv_refcnt = 1; 69 smb_vfs->sv_vfsp = vfsp; 70 /* 71 * We have a hold on the root vnode of the file system 72 * from the VFS_ROOT call above. 73 */ 74 smb_vfs->sv_rootvp = rootvp; 75 76 smb_llist_insert_head(&se->e_vfs_list, smb_vfs); 77 DTRACE_PROBE1(smb_vfs_hold_miss, smb_vfs_t *, smb_vfs); 78 smb_llist_exit(&se->e_vfs_list); 79 80 return (0); 81 } 82 83 /* 84 * smb_vfs_rele 85 * 86 * Decrements the reference count of the fs passed in. If the reference count 87 * drops to zero the smb_vfs_t structure associated with the fs is freed. 88 */ 89 void 90 smb_vfs_rele(smb_export_t *se, vfs_t *vfsp) 91 { 92 smb_vfs_t *smb_vfs; 93 94 ASSERT(vfsp); 95 96 smb_llist_enter(&se->e_vfs_list, RW_WRITER); 97 smb_vfs = smb_vfs_find(se, vfsp); 98 DTRACE_PROBE1(smb_vfs_release, smb_vfs_t *, smb_vfs) 99 if (smb_vfs) { 100 ASSERT(smb_vfs->sv_refcnt); 101 if (--smb_vfs->sv_refcnt == 0) { 102 smb_llist_remove(&se->e_vfs_list, smb_vfs); 103 smb_llist_exit(&se->e_vfs_list); 104 smb_vfs_destroy(se, smb_vfs); 105 return; 106 } 107 } 108 smb_llist_exit(&se->e_vfs_list); 109 } 110 111 /* 112 * smb_vfs_rele_all() 113 * 114 * Release all holds on root vnodes of file systems which were taken 115 * due to the existence of at least one enabled share on the file system. 116 * Called at driver close time. 117 */ 118 void 119 smb_vfs_rele_all(smb_export_t *se) 120 { 121 smb_vfs_t *smb_vfs; 122 123 smb_llist_enter(&se->e_vfs_list, RW_WRITER); 124 while ((smb_vfs = smb_llist_head(&se->e_vfs_list)) != NULL) { 125 126 ASSERT(smb_vfs->sv_magic == SMB_VFS_MAGIC); 127 DTRACE_PROBE1(smb_vfs_rele_all_hit, smb_vfs_t *, smb_vfs); 128 smb_llist_remove(&se->e_vfs_list, smb_vfs); 129 smb_vfs_destroy(se, smb_vfs); 130 } 131 smb_llist_exit(&se->e_vfs_list); 132 } 133 134 /* 135 * Goes through the list of smb_vfs_t structure and returns the one matching 136 * the vnode passed in. If no match is found a NULL pointer is returned. 137 * 138 * The list of smb_vfs_t structures has to have been entered prior calling 139 * this function. 140 */ 141 static smb_vfs_t * 142 smb_vfs_find(smb_export_t *se, vfs_t *vfsp) 143 { 144 smb_vfs_t *smb_vfs; 145 146 smb_vfs = smb_llist_head(&se->e_vfs_list); 147 while (smb_vfs) { 148 ASSERT(smb_vfs->sv_magic == SMB_VFS_MAGIC); 149 if (smb_vfs->sv_vfsp == vfsp) 150 return (smb_vfs); 151 smb_vfs = smb_llist_next(&se->e_vfs_list, smb_vfs); 152 } 153 154 return (NULL); 155 } 156 157 static void 158 smb_vfs_destroy(smb_export_t *se, smb_vfs_t *smb_vfs) 159 { 160 VN_RELE(smb_vfs->sv_rootvp); 161 smb_vfs->sv_magic = (uint32_t)~SMB_VFS_MAGIC; 162 kmem_cache_free(se->e_cache_vfs, smb_vfs); 163 } 164