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 <smbsrv/smb_incl.h> 29 #include <smbsrv/smb_fsops.h> 30 #include <sys/vfs.h> 31 32 static smb_vfs_t *smb_vfs_lookup(vnode_t *); 33 34 /* 35 * smb_vfs_hold 36 * 37 * Increments the reference count of the fs passed in. If no smb_vfs_t structure 38 * has been created yet for the fs passed in it is created. 39 */ 40 boolean_t 41 smb_vfs_hold(vfs_t *vfsp) 42 { 43 smb_vfs_t *smb_vfs; 44 vnode_t *rootvp; 45 46 if ((vfsp == NULL) || VFS_ROOT(vfsp, &rootvp)) 47 return (B_FALSE); 48 49 smb_llist_enter(&smb_info.si_vfs_list, RW_WRITER); 50 smb_vfs = smb_vfs_lookup(rootvp); 51 if (smb_vfs) { 52 DTRACE_PROBE1(smb_vfs_hold_hit, smb_vfs_t *, smb_vfs); 53 smb_llist_exit(&smb_info.si_vfs_list); 54 VN_RELE(rootvp); 55 return (B_TRUE); 56 } 57 smb_vfs = kmem_cache_alloc(smb_info.si_cache_vfs, KM_SLEEP); 58 59 bzero(smb_vfs, sizeof (smb_vfs_t)); 60 61 smb_vfs->sv_magic = SMB_VFS_MAGIC; 62 smb_vfs->sv_refcnt = 1; 63 smb_vfs->sv_vfsp = vfsp; 64 /* 65 * We have a hold on the root vnode of the file system 66 * from the VFS_ROOT call above. 67 */ 68 smb_vfs->sv_rootvp = rootvp; 69 smb_llist_insert_head(&smb_info.si_vfs_list, smb_vfs); 70 DTRACE_PROBE1(smb_vfs_hold_miss, smb_vfs_t *, smb_vfs); 71 smb_llist_exit(&smb_info.si_vfs_list); 72 return (B_TRUE); 73 } 74 75 /* 76 * smb_vfs_rele 77 * 78 * Decrements the reference count of the fs passed in. If the reference count 79 * drops to zero the smb_vfs_t structure associated with the fs is freed. 80 */ 81 void 82 smb_vfs_rele(vfs_t *vfsp) 83 { 84 smb_vfs_t *smb_vfs; 85 vnode_t *rootvp; 86 87 ASSERT(vfsp); 88 89 if (VFS_ROOT(vfsp, &rootvp)) 90 return; 91 92 smb_llist_enter(&smb_info.si_vfs_list, RW_WRITER); 93 smb_vfs = smb_vfs_lookup(rootvp); 94 DTRACE_PROBE2(smb_vfs_release, smb_vfs_t *, smb_vfs, vnode_t *, rootvp); 95 VN_RELE(rootvp); 96 if (smb_vfs) { 97 --smb_vfs->sv_refcnt; 98 ASSERT(smb_vfs->sv_refcnt); 99 if (--smb_vfs->sv_refcnt == 0) { 100 smb_llist_remove(&smb_info.si_vfs_list, smb_vfs); 101 smb_llist_exit(&smb_info.si_vfs_list); 102 ASSERT(rootvp == smb_vfs->sv_rootvp); 103 VN_RELE(smb_vfs->sv_rootvp); 104 smb_vfs->sv_magic = (uint32_t)~SMB_VFS_MAGIC; 105 kmem_cache_free(smb_info.si_cache_vfs, smb_vfs); 106 return; 107 } 108 } 109 smb_llist_exit(&smb_info.si_vfs_list); 110 } 111 112 /* 113 * smb_vfs_rele_all() 114 * 115 * Release all holds on root vnodes of file systems which were taken 116 * due to the existence of at least one enabled share on the file system. 117 * Called at driver close time. 118 */ 119 void 120 smb_vfs_rele_all() 121 { 122 smb_vfs_t *smb_vfs; 123 124 smb_llist_enter(&smb_info.si_vfs_list, RW_WRITER); 125 while ((smb_vfs = smb_llist_head(&smb_info.si_vfs_list)) != NULL) { 126 127 ASSERT(smb_vfs->sv_magic == SMB_VFS_MAGIC); 128 DTRACE_PROBE1(smb_vfs_rele_all_hit, smb_vfs_t *, smb_vfs); 129 smb_llist_remove(&smb_info.si_vfs_list, smb_vfs); 130 VN_RELE(smb_vfs->sv_rootvp); 131 kmem_cache_free(smb_info.si_cache_vfs, smb_vfs); 132 } 133 smb_llist_exit(&smb_info.si_vfs_list); 134 } 135 136 /* 137 * smb_vfs_lookup 138 * 139 * Goes through the list of smb_vfs_t structure and returns the one matching 140 * the vnode passed in. If no match is found a NULL pointer is returned. 141 * 142 * The list of smb_vfs_t structures has to have been entered prior calling 143 * this function. 144 */ 145 static smb_vfs_t * 146 smb_vfs_lookup(vnode_t *rootvp) 147 { 148 smb_vfs_t *smb_vfs; 149 150 smb_vfs = smb_llist_head(&smb_info.si_vfs_list); 151 while (smb_vfs) { 152 ASSERT(smb_vfs->sv_magic == SMB_VFS_MAGIC); 153 if (smb_vfs->sv_rootvp == rootvp) { 154 smb_vfs->sv_refcnt++; 155 ASSERT(smb_vfs->sv_refcnt); 156 return (smb_vfs); 157 } 158 smb_vfs = smb_llist_next(&smb_info.si_vfs_list, smb_vfs); 159 } 160 return (NULL); 161 } 162