1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
9
10 #ifndef __GLOCK_DOT_H__
11 #define __GLOCK_DOT_H__
12
13 #include <linux/sched.h>
14 #include <linux/parser.h>
15 #include "incore.h"
16
17 /* Options for hostdata parser */
18
19 enum {
20 Opt_jid,
21 Opt_id,
22 Opt_first,
23 Opt_nodir,
24 Opt_err,
25 };
26
27 /*
28 * lm_lockname types
29 */
30
31 #define LM_TYPE_RESERVED 0x00
32 #define LM_TYPE_NONDISK 0x01
33 #define LM_TYPE_INODE 0x02
34 #define LM_TYPE_RGRP 0x03
35 #define LM_TYPE_META 0x04
36 #define LM_TYPE_IOPEN 0x05
37 #define LM_TYPE_FLOCK 0x06
38 #define LM_TYPE_PLOCK 0x07
39 #define LM_TYPE_QUOTA 0x08
40 #define LM_TYPE_JOURNAL 0x09
41
42 /*
43 * lm_lock() states
44 *
45 * SHARED is compatible with SHARED, not with DEFERRED or EX.
46 * DEFERRED is compatible with DEFERRED, not with SHARED or EX.
47 */
48
49 #define LM_ST_UNLOCKED 0
50 #define LM_ST_EXCLUSIVE 1
51 #define LM_ST_DEFERRED 2
52 #define LM_ST_SHARED 3
53
54 /*
55 * lm_lock() flags
56 *
57 * LM_FLAG_TRY
58 * Don't wait to acquire the lock if it can't be granted immediately.
59 *
60 * LM_FLAG_TRY_1CB
61 * Send one blocking callback if TRY is set and the lock is not granted.
62 *
63 * LM_FLAG_NOEXP
64 * GFS sets this flag on lock requests it makes while doing journal recovery.
65 * These special requests should not be blocked due to the recovery like
66 * ordinary locks would be.
67 *
68 * LM_FLAG_ANY
69 * A SHARED request may also be granted in DEFERRED, or a DEFERRED request may
70 * also be granted in SHARED. The preferred state is whichever is compatible
71 * with other granted locks, or the specified state if no other locks exist.
72 *
73 * LM_FLAG_PRIORITY
74 * Override fairness considerations. Suppose a lock is held in a shared state
75 * and there is a pending request for the deferred state. A shared lock
76 * request with the priority flag would be allowed to bypass the deferred
77 * request and directly join the other shared lock. A shared lock request
78 * without the priority flag might be forced to wait until the deferred
79 * requested had acquired and released the lock.
80 */
81
82 #define LM_FLAG_TRY 0x0001
83 #define LM_FLAG_TRY_1CB 0x0002
84 #define LM_FLAG_NOEXP 0x0004
85 #define LM_FLAG_ANY 0x0008
86 #define LM_FLAG_PRIORITY 0x0010
87 #define GL_ASYNC 0x0040
88 #define GL_EXACT 0x0080
89 #define GL_SKIP 0x0100
90 #define GL_NOCACHE 0x0400
91
92 /*
93 * lm_async_cb return flags
94 *
95 * LM_OUT_ST_MASK
96 * Masks the lower two bits of lock state in the returned value.
97 *
98 * LM_OUT_CANCELED
99 * The lock request was canceled.
100 *
101 */
102
103 #define LM_OUT_ST_MASK 0x00000003
104 #define LM_OUT_CANCELED 0x00000008
105 #define LM_OUT_ERROR 0x00000004
106
107 /*
108 * lm_recovery_done() messages
109 */
110
111 #define LM_RD_GAVEUP 308
112 #define LM_RD_SUCCESS 309
113
114 #define GLR_TRYFAILED 13
115
116 #define GL_GLOCK_MAX_HOLD (long)(HZ / 5)
117 #define GL_GLOCK_DFT_HOLD (long)(HZ / 5)
118 #define GL_GLOCK_MIN_HOLD (long)(10)
119 #define GL_GLOCK_HOLD_INCR (long)(HZ / 20)
120 #define GL_GLOCK_HOLD_DECR (long)(HZ / 40)
121
122 struct lm_lockops {
123 const char *lm_proto_name;
124 int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
125 void (*lm_first_done) (struct gfs2_sbd *sdp);
126 void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
127 unsigned int result);
128 void (*lm_unmount) (struct gfs2_sbd *sdp);
129 void (*lm_withdraw) (struct gfs2_sbd *sdp);
130 void (*lm_put_lock) (struct gfs2_glock *gl);
131 int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
132 unsigned int flags);
133 void (*lm_cancel) (struct gfs2_glock *gl);
134 const match_table_t *lm_tokens;
135 };
136
137 extern struct workqueue_struct *gfs2_delete_workqueue;
gfs2_glock_is_locked_by_me(struct gfs2_glock * gl)138 static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
139 {
140 struct gfs2_holder *gh;
141 struct pid *pid;
142
143 /* Look in glock's list of holders for one with current task as owner */
144 spin_lock(&gl->gl_lockref.lock);
145 pid = task_pid(current);
146 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
147 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
148 break;
149 if (gh->gh_owner_pid == pid)
150 goto out;
151 }
152 gh = NULL;
153 out:
154 spin_unlock(&gl->gl_lockref.lock);
155
156 return gh;
157 }
158
gfs2_glock_is_held_excl(struct gfs2_glock * gl)159 static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
160 {
161 return gl->gl_state == LM_ST_EXCLUSIVE;
162 }
163
gfs2_glock_is_held_dfrd(struct gfs2_glock * gl)164 static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
165 {
166 return gl->gl_state == LM_ST_DEFERRED;
167 }
168
gfs2_glock_is_held_shrd(struct gfs2_glock * gl)169 static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
170 {
171 return gl->gl_state == LM_ST_SHARED;
172 }
173
gfs2_glock2aspace(struct gfs2_glock * gl)174 static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl)
175 {
176 if (gl->gl_ops->go_flags & GLOF_ASPACE)
177 return (struct address_space *)(gl + 1);
178 return NULL;
179 }
180
181 extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
182 const struct gfs2_glock_operations *glops,
183 int create, struct gfs2_glock **glp);
184 extern void gfs2_glock_put(struct gfs2_glock *gl);
185 extern void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
186 u16 flags, struct gfs2_holder *gh);
187 extern void gfs2_holder_reinit(unsigned int state, u16 flags,
188 struct gfs2_holder *gh);
189 extern void gfs2_holder_uninit(struct gfs2_holder *gh);
190 extern int gfs2_glock_nq(struct gfs2_holder *gh);
191 extern int gfs2_glock_poll(struct gfs2_holder *gh);
192 extern int gfs2_glock_wait(struct gfs2_holder *gh);
193 extern void gfs2_glock_dq(struct gfs2_holder *gh);
194 extern void gfs2_glock_dq_wait(struct gfs2_holder *gh);
195 extern void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
196 extern int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
197 const struct gfs2_glock_operations *glops,
198 unsigned int state, u16 flags,
199 struct gfs2_holder *gh);
200 extern int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
201 extern void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
202 extern void gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl);
203 #define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { gfs2_dump_glock(NULL, gl); BUG(); } } while(0)
204 extern __printf(2, 3)
205 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
206
207 /**
208 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
209 * @gl: the glock
210 * @state: the state we're requesting
211 * @flags: the modifier flags
212 * @gh: the holder structure
213 *
214 * Returns: 0, GLR_*, or errno
215 */
216
gfs2_glock_nq_init(struct gfs2_glock * gl,unsigned int state,u16 flags,struct gfs2_holder * gh)217 static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
218 unsigned int state, u16 flags,
219 struct gfs2_holder *gh)
220 {
221 int error;
222
223 gfs2_holder_init(gl, state, flags, gh);
224
225 error = gfs2_glock_nq(gh);
226 if (error)
227 gfs2_holder_uninit(gh);
228
229 return error;
230 }
231
232 extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
233 extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
234 extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
235 extern void gfs2_glock_finish_truncate(struct gfs2_inode *ip);
236 extern void gfs2_glock_thaw(struct gfs2_sbd *sdp);
237 extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
238 extern void gfs2_glock_free(struct gfs2_glock *gl);
239
240 extern int __init gfs2_glock_init(void);
241 extern void gfs2_glock_exit(void);
242
243 extern int gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
244 extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
245 extern int gfs2_register_debugfs(void);
246 extern void gfs2_unregister_debugfs(void);
247
248 extern const struct lm_lockops gfs2_dlm_ops;
249
gfs2_holder_mark_uninitialized(struct gfs2_holder * gh)250 static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
251 {
252 gh->gh_gl = NULL;
253 }
254
gfs2_holder_initialized(struct gfs2_holder * gh)255 static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
256 {
257 return gh->gh_gl;
258 }
259
260 #endif /* __GLOCK_DOT_H__ */
261