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