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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23 /*
24 * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
25 */
26
27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29
30
31 /*
32 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
33 * Use is subject to license terms.
34 */
35 /*
36 * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
37 * Copyright 2015 Joyent, Inc.
38 */
39
40 #ifndef _SYS_FLOCK_H
41 #define _SYS_FLOCK_H
42
43 #include <sys/types.h>
44 #include <sys/fcntl.h>
45 #include <sys/vnode.h>
46 #include <sys/t_lock.h> /* for <sys/callb.h> */
47 #include <sys/callb.h>
48 #include <sys/param.h>
49 #include <sys/zone.h>
50 #if defined(_KERNEL)
51 #include <sys/file.h>
52 #endif
53
54 #ifdef __cplusplus
55 extern "C" {
56 #endif
57
58 /*
59 * Private declarations and instrumentation for local locking.
60 */
61
62 /*
63 * The flag passed to fs_frlock() may be ORed together with either
64 * `F_REMOTELOCK' or `F_PXFSLOCK'. Since this flag is initialized using the
65 * `f_flag' field in the `file' structure, and that field is an unsigned short,
66 * we do not use the first 2 bytes.
67 */
68 #define F_REMOTELOCK (0x01 << 16) /* Set if NLM lock */
69 #define F_PXFSLOCK (0x02 << 16) /* Clustering: set if PXFS lock */
70
71 /*
72 * The command passed to reclock() is made by ORing together one or more of
73 * the following values.
74 */
75
76 #define INOFLCK 0x01 /* Vnode is locked when reclock() is called. */
77 #define SETFLCK 0x02 /* Set a file lock. */
78 #define SLPFLCK 0x04 /* Wait if blocked. */
79 #define RCMDLCK 0x08 /* F_REMOTELOCK specified */
80 #define PCMDLCK 0x10 /* Clustering: F_PXFSLOCK specified */
81 #define NBMLCK 0x20 /* non-blocking mandatory locking */
82
83 /*
84 * Special pid value that can be passed to cleanlocks(). It means that
85 * cleanlocks() should flush all locks for the given sysid, not just the
86 * locks owned by a specific process.
87 */
88
89 #define IGN_PID (-1)
90
91 /* file locking structure (connected to vnode) */
92
93 #define l_end l_len
94
95 /*
96 * The lock manager is allowed to use unsigned offsets and lengths, though
97 * regular Unix processes are still required to use signed offsets and
98 * lengths.
99 */
100 typedef ulong_t u_off_t;
101
102 #define MAX_U_OFF_T ((u_off_t)~0)
103 #define MAX_U_OFFSET_T ((u_offset_t)~0)
104
105 /*
106 * define MAXEND as the largest positive value the signed offset_t will hold.
107 */
108 #define MAXEND MAXOFFSET_T
109
110 /*
111 * Definitions for accessing the l_pad area of struct flock. The
112 * descriminant of the pad_info_t union is the fcntl command used in
113 * conjunction with the flock struct.
114 */
115
116 typedef union {
117 int pi_pad[4]; /* (original pad area) */
118 int pi_has_rmt; /* F_HASREMOTELOCKS */
119 } pad_info_t;
120
121 #define l_has_rmt(flockp) (((pad_info_t *)((flockp)->l_pad))->pi_has_rmt)
122
123 /*
124 * Optional callbacks for blocking lock requests. Each function is called
125 * twice.
126 * The first call is after the request is put in the "sleeping" list, but
127 * before waiting. At most one callback may return a callb_cpr_t object;
128 * the others must return NULL. If a callb_cpr_t is returned, the thread
129 * will be marked as safe to suspend while waiting for the lock.
130 * The second call is after the request wakes up. Note that the request
131 * might not have been granted at the second call (e.g., the request was
132 * signalled).
133 * New callbacks should be added to the head of the list. For the first
134 * call the list is walked in order. For the second call the list is
135 * walked backwards (in case the callbacks need to reacquire locks).
136 */
137
138 typedef enum {FLK_BEFORE_SLEEP, FLK_AFTER_SLEEP} flk_cb_when_t;
139
140 struct flk_callback {
141 struct flk_callback *cb_next; /* circular linked list */
142 struct flk_callback *cb_prev;
143 callb_cpr_t *(*cb_callback)(flk_cb_when_t, void *); /* fcn ptr */
144 void *cb_data; /* ptr to callback data */
145 };
146
147 typedef struct flk_callback flk_callback_t;
148
149 /*
150 * This structure members are not used any more inside the kernel.
151 * The structure is used for casting some pointer assignments only.
152 */
153
154 typedef struct filock {
155 kcondvar_t cv;
156 struct flock set; /* contains type, start, and end */
157 struct {
158 int granted_flag; /* granted flag */
159 struct filock *blk; /* for sleeping locks only */
160 struct attacher *blocking_list;
161 struct attacher *my_attacher;
162 } stat;
163 struct filock *prev;
164 struct filock *next;
165 } filock_t;
166
167 #define FLP_DELAYED_FREE -1 /* special value for granted_flag */
168
169 /* structure that contains list of locks to be granted */
170
171 #define MAX_GRANT_LOCKS 52
172
173 typedef struct grant_lock {
174 struct filock *grant_lock_list[MAX_GRANT_LOCKS];
175 struct grant_lock *next;
176 } grant_lock_t;
177
178 /*
179 * Provide a way to cleanly enable and disable Network Lock Manager locking
180 * requests (i.e., requests from remote clients):
181 * FLK_NLM_SHUTTING_DOWN: Forces all blocked NLM requests to bail out
182 * and return ENOLCK.
183 * FLK_NLM_DOWN: Clears all granted NLM server locks. Both status
184 * codes cause new NLM lock requests to fail immediately with ENOLCK.
185 * FLK_NLM_UP: Changes the state of all locks to UP, after a server has
186 * shutdown and is restarting on the same node.
187 */
188
189 /*
190 * Enumerated type of the four possible states an NLM server can be in.
191 */
192 typedef enum {
193 FLK_NLM_UP,
194 FLK_NLM_SHUTTING_DOWN,
195 FLK_NLM_DOWN,
196 FLK_NLM_UNKNOWN
197 } flk_nlm_status_t;
198
199 /*
200 * Provide a way to cleanly enable and disable lock manager locking
201 * requests (i.e., requests from remote clients). FLK_WAKEUP_SLEEPERS
202 * forces all blocked lock manager requests to bail out and return ENOLCK.
203 * FLK_LOCKMGR_DOWN clears all granted lock manager locks. Both status
204 * codes cause new lock manager requests to fail immediately with ENOLCK.
205 */
206
207 typedef enum {
208 FLK_LOCKMGR_UP,
209 FLK_WAKEUP_SLEEPERS,
210 FLK_LOCKMGR_DOWN
211 } flk_lockmgr_status_t;
212
213 #if defined(_KERNEL) || defined(_FAKE_KERNEL)
214
215 /*
216 * The following structure is used to hold a list of locks returned
217 * by the F_ACTIVELIST or F_SLEEPINGLIST commands to fs_frlock.
218 *
219 * N.B. The lists returned by these commands are dynamically
220 * allocated and must be freed by the caller. The vnodes returned
221 * in the lists are held and must be released when the caller is done.
222 */
223
224 typedef struct locklist {
225 struct vnode *ll_vp;
226 struct flock64 ll_flock;
227 struct locklist *ll_next;
228 } locklist_t;
229
230 #define FLK_QUERY_ACTIVE 0x1
231 #define FLK_QUERY_SLEEPING 0x2
232
233 #if defined(_KERNEL)
234 int ofdlock(file_t *, int, struct flock64 *, int, u_offset_t);
235 void ofdcleanlock(file_t *);
236 #endif
237 int reclock(struct vnode *, struct flock64 *, int, int, u_offset_t,
238 flk_callback_t *);
239 int chklock(struct vnode *, int, u_offset_t, ssize_t, int,
240 caller_context_t *);
241 int convoff(struct vnode *, struct flock64 *, int, offset_t);
242 void cleanlocks(struct vnode *, pid_t, int);
243 locklist_t *flk_get_sleeping_locks(int sysid, pid_t pid);
244 locklist_t *flk_get_active_locks(int sysid, pid_t pid);
245 locklist_t *flk_active_locks_for_vp(const struct vnode *vp);
246 locklist_t *flk_active_nbmand_locks_for_vp(const struct vnode *vp);
247 locklist_t *flk_active_nbmand_locks(pid_t pid);
248 void flk_free_locklist(locklist_t *);
249 int flk_convert_lock_data(struct vnode *, struct flock64 *,
250 u_offset_t *, u_offset_t *, offset_t);
251 int flk_check_lock_data(u_offset_t, u_offset_t, offset_t);
252 int flk_has_remote_locks(struct vnode *vp);
253 void flk_set_lockmgr_status(flk_lockmgr_status_t status);
254 int flk_sysid_has_locks(int sysid, int chklck);
255 int flk_has_remote_locks_for_sysid(vnode_t *vp, int);
256 void flk_init_callback(flk_callback_t *,
257 callb_cpr_t *(*)(flk_cb_when_t, void *), void *);
258 void flk_add_callback(flk_callback_t *,
259 callb_cpr_t *(*)(flk_cb_when_t, void *), void *,
260 flk_callback_t *);
261 void flk_del_callback(flk_callback_t *);
262 callb_cpr_t *flk_invoke_callbacks(flk_callback_t *, flk_cb_when_t);
263
264 /* Zones hooks */
265 extern zone_key_t flock_zone_key;
266
267 void *flk_zone_init(zoneid_t);
268 void flk_zone_fini(zoneid_t, void *);
269
270 /* Clustering hooks */
271 void cl_flk_set_nlm_status(int nlmid, flk_nlm_status_t nlm_state);
272 void cl_flk_remove_locks_by_sysid(int sysid);
273 int cl_flk_has_remote_locks_for_nlmid(struct vnode *vp, int nlmid);
274 void cl_flk_change_nlm_state_to_unknown(int nlmid);
275 void cl_flk_delete_pxfs_locks(struct vfs *vfsp, int pxfsid);
276
277 /* Support for the remote stale lock detection */
278 struct sockaddr;
279
280 typedef int (*sysid_to_host_translator_t)(zoneid_t, sysid_t, struct sockaddr *,
281 const char **);
282
283 void flk_add_sysid_to_host_translator(sysid_to_host_translator_t);
284 #endif /* _KERNEL */
285
286 #ifdef __cplusplus
287 }
288 #endif
289
290 #endif /* _SYS_FLOCK_H */