1/* 2 Unix SMB/CIFS implementation. 3 4 generic byte range locking code 5 6 Copyright (C) Andrew Tridgell 1992-2004 7 Copyright (C) Jeremy Allison 1992-2000 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program. If not, see <http://www.gnu.org/licenses/>. 21*/ 22 23/* This module implements a tdb based byte range locking service, 24 replacing the fcntl() based byte range locking previously 25 used. This allows us to provide the same semantics as NT */ 26 27#include "includes.h" 28#include "system/filesys.h" 29#include "../tdb/include/tdb.h" 30#include "messaging/messaging.h" 31#include "lib/messaging/irpc.h" 32#include "libcli/libcli.h" 33#include "cluster/cluster.h" 34#include "ntvfs/common/ntvfs_common.h" 35 36static const struct brlock_ops *ops; 37 38/* 39 set the brl backend ops 40*/ 41void brl_set_ops(const struct brlock_ops *new_ops) 42{ 43 ops = new_ops; 44} 45 46/* 47 Open up the brlock database. Close it down using talloc_free(). We 48 need the messaging_ctx to allow for pending lock notifications. 49*/ 50struct brl_context *brl_init(TALLOC_CTX *mem_ctx, struct server_id server, 51 struct loadparm_context *lp_ctx, 52 struct messaging_context *messaging_ctx) 53{ 54 if (ops == NULL) { 55 brl_tdb_init_ops(); 56 } 57 return ops->brl_init(mem_ctx, server, lp_ctx, messaging_ctx); 58} 59 60struct brl_handle *brl_create_handle(TALLOC_CTX *mem_ctx, struct ntvfs_handle *ntvfs, DATA_BLOB *file_key) 61{ 62 return ops->brl_create_handle(mem_ctx, ntvfs, file_key); 63} 64 65/* 66 Lock a range of bytes. The lock_type can be a PENDING_*_LOCK, in 67 which case a real lock is first tried, and if that fails then a 68 pending lock is created. When the pending lock is triggered (by 69 someone else closing an overlapping lock range) a messaging 70 notification is sent, identified by the notify_ptr 71*/ 72NTSTATUS brl_lock(struct brl_context *brl, 73 struct brl_handle *brlh, 74 uint32_t smbpid, 75 uint64_t start, uint64_t size, 76 enum brl_type lock_type, 77 void *notify_ptr) 78{ 79 return ops->brl_lock(brl, brlh, smbpid, start, size, lock_type, notify_ptr); 80} 81 82 83/* 84 Unlock a range of bytes. 85*/ 86NTSTATUS brl_unlock(struct brl_context *brl, 87 struct brl_handle *brlh, 88 uint32_t smbpid, 89 uint64_t start, uint64_t size) 90{ 91 return ops->brl_unlock(brl, brlh, smbpid, start, size); 92} 93 94/* 95 remove a pending lock. This is called when the caller has either 96 given up trying to establish a lock or when they have succeeded in 97 getting it. In either case they no longer need to be notified. 98*/ 99NTSTATUS brl_remove_pending(struct brl_context *brl, 100 struct brl_handle *brlh, 101 void *notify_ptr) 102{ 103 return ops->brl_remove_pending(brl, brlh, notify_ptr); 104} 105 106 107/* 108 Test if we are allowed to perform IO on a region of an open file 109*/ 110NTSTATUS brl_locktest(struct brl_context *brl, 111 struct brl_handle *brlh, 112 uint32_t smbpid, 113 uint64_t start, uint64_t size, 114 enum brl_type lock_type) 115{ 116 return ops->brl_locktest(brl, brlh, smbpid, start, size, lock_type); 117} 118 119 120/* 121 Remove any locks associated with a open file. 122*/ 123NTSTATUS brl_close(struct brl_context *brl, 124 struct brl_handle *brlh) 125{ 126 return ops->brl_close(brl, brlh); 127} 128