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