1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
4 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
5 */
6
7 #ifndef __GLOCK_DOT_H__
8 #define __GLOCK_DOT_H__
9
10 #include <linux/sched.h>
11 #include <linux/parser.h>
12 #include "incore.h"
13 #include "util.h"
14
15 /* Options for hostdata parser */
16
17 enum {
18 Opt_jid,
19 Opt_id,
20 Opt_first,
21 Opt_nodir,
22 Opt_err,
23 };
24
25 /*
26 * lm_lockname types
27 */
28
29 #define LM_TYPE_RESERVED 0x00
30 #define LM_TYPE_NONDISK 0x01
31 #define LM_TYPE_INODE 0x02
32 #define LM_TYPE_RGRP 0x03
33 #define LM_TYPE_META 0x04
34 #define LM_TYPE_IOPEN 0x05
35 #define LM_TYPE_FLOCK 0x06
36 #define LM_TYPE_PLOCK 0x07
37 #define LM_TYPE_QUOTA 0x08
38 #define LM_TYPE_JOURNAL 0x09
39
40 /*
41 * lm_lock() states
42 *
43 * SHARED is compatible with SHARED, not with DEFERRED or EX.
44 * DEFERRED is compatible with DEFERRED, not with SHARED or EX.
45 */
46
47 #define LM_ST_UNLOCKED 0
48 #define LM_ST_EXCLUSIVE 1
49 #define LM_ST_DEFERRED 2
50 #define LM_ST_SHARED 3
51
52 /*
53 * lm_lock() flags
54 *
55 * LM_FLAG_TRY
56 * Don't wait to acquire the lock if it can't be granted immediately.
57 *
58 * LM_FLAG_TRY_1CB
59 * Send one blocking callback if TRY is set and the lock is not granted.
60 *
61 * LM_FLAG_NOEXP
62 * GFS sets this flag on lock requests it makes while doing journal recovery.
63 * These special requests should not be blocked due to the recovery like
64 * ordinary locks would be.
65 *
66 * LM_FLAG_ANY
67 * A SHARED request may also be granted in DEFERRED, or a DEFERRED request may
68 * also be granted in SHARED. The preferred state is whichever is compatible
69 * with other granted locks, or the specified state if no other locks exist.
70 *
71 * LM_FLAG_NODE_SCOPE
72 * This holder agrees to share the lock within this node. In other words,
73 * the glock is held in EX mode according to DLM, but local holders on the
74 * same node can share it.
75 */
76
77 #define LM_FLAG_TRY 0x0001
78 #define LM_FLAG_TRY_1CB 0x0002
79 #define LM_FLAG_NOEXP 0x0004
80 #define LM_FLAG_ANY 0x0008
81 #define LM_FLAG_NODE_SCOPE 0x0020
82 #define GL_ASYNC 0x0040
83 #define GL_EXACT 0x0080
84 #define GL_SKIP 0x0100
85 #define GL_NOPID 0x0200
86 #define GL_NOCACHE 0x0400
87 #define GL_NOBLOCK 0x0800
88
89 /*
90 * lm_async_cb return flags
91 *
92 * LM_OUT_ST_MASK
93 * Masks the lower two bits of lock state in the returned value.
94 *
95 * LM_OUT_TRY_AGAIN
96 * The trylock request failed.
97 *
98 * LM_OUT_DEADLOCK
99 * The lock request failed because it would deadlock.
100 *
101 * LM_OUT_CANCELED
102 * The lock request was canceled.
103 *
104 * LM_OUT_ERROR
105 * The lock request timed out or failed.
106 */
107
108 #define LM_OUT_ST_MASK 0x00000003
109 #define LM_OUT_TRY_AGAIN 0x00000020
110 #define LM_OUT_DEADLOCK 0x00000010
111 #define LM_OUT_CANCELED 0x00000008
112 #define LM_OUT_ERROR 0x00000004
113
114 /*
115 * lm_recovery_done() messages
116 */
117
118 #define LM_RD_GAVEUP 308
119 #define LM_RD_SUCCESS 309
120
121 #define GLR_TRYFAILED 13
122
123 #define GL_GLOCK_MAX_HOLD (long)(HZ / 5)
124 #define GL_GLOCK_DFT_HOLD (long)(HZ / 5)
125 #define GL_GLOCK_MIN_HOLD (long)(10)
126 #define GL_GLOCK_HOLD_INCR (long)(HZ / 20)
127 #define GL_GLOCK_HOLD_DECR (long)(HZ / 40)
128
129 struct lm_lockops {
130 const char *lm_proto_name;
131 int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
132 void (*lm_first_done) (struct gfs2_sbd *sdp);
133 void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
134 unsigned int result);
135 void (*lm_unmount) (struct gfs2_sbd *sdp);
136 void (*lm_withdraw) (struct gfs2_sbd *sdp);
137 void (*lm_put_lock) (struct gfs2_glock *gl);
138 int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
139 unsigned int flags);
140 void (*lm_cancel) (struct gfs2_glock *gl);
141 const match_table_t *lm_tokens;
142 };
143
144 struct gfs2_glock_aspace {
145 struct gfs2_glock glock;
146 struct address_space mapping;
147 };
148
gfs2_glock_is_locked_by_me(struct gfs2_glock * gl)149 static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
150 {
151 struct gfs2_holder *gh;
152 struct pid *pid;
153
154 /* Look in glock's list of holders for one with current task as owner */
155 spin_lock(&gl->gl_lockref.lock);
156 pid = task_pid(current);
157 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
158 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
159 break;
160 if (gh->gh_owner_pid == pid)
161 goto out;
162 }
163 gh = NULL;
164 out:
165 spin_unlock(&gl->gl_lockref.lock);
166
167 return gh;
168 }
169
gfs2_glock2aspace(struct gfs2_glock * gl)170 static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl)
171 {
172 if (gl->gl_ops->go_flags & GLOF_ASPACE) {
173 struct gfs2_glock_aspace *gla =
174 container_of(gl, struct gfs2_glock_aspace, glock);
175 return &gla->mapping;
176 }
177 return NULL;
178 }
179
180 int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
181 const struct gfs2_glock_operations *glops,
182 int create, struct gfs2_glock **glp);
183 struct gfs2_glock *gfs2_glock_hold(struct gfs2_glock *gl);
184 void gfs2_glock_put(struct gfs2_glock *gl);
185 void gfs2_glock_put_async(struct gfs2_glock *gl);
186
187 void __gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
188 u16 flags, struct gfs2_holder *gh,
189 unsigned long ip);
gfs2_holder_init(struct gfs2_glock * gl,unsigned int state,u16 flags,struct gfs2_holder * gh)190 static inline void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
191 u16 flags, struct gfs2_holder *gh) {
192 __gfs2_holder_init(gl, state, flags, gh, _RET_IP_);
193 }
194
195 void gfs2_holder_reinit(unsigned int state, u16 flags,
196 struct gfs2_holder *gh);
197 void gfs2_holder_uninit(struct gfs2_holder *gh);
198 int gfs2_glock_nq(struct gfs2_holder *gh);
199 int gfs2_glock_poll(struct gfs2_holder *gh);
200 int gfs2_instantiate(struct gfs2_holder *gh);
201 int gfs2_glock_holder_ready(struct gfs2_holder *gh);
202 int gfs2_glock_wait(struct gfs2_holder *gh);
203 int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs);
204 void gfs2_glock_dq(struct gfs2_holder *gh);
205 void gfs2_glock_dq_wait(struct gfs2_holder *gh);
206 void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
207 int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
208 const struct gfs2_glock_operations *glops,
209 unsigned int state, u16 flags,
210 struct gfs2_holder *gh);
211 int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
212 void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
213 void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl,
214 bool fsid);
215 #define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { \
216 gfs2_dump_glock(NULL, gl, true); \
217 BUG(); } } while(0)
218 #define gfs2_glock_assert_warn(gl, x) do { if (unlikely(!(x))) { \
219 gfs2_dump_glock(NULL, gl, true); \
220 gfs2_assert_warn((gl)->gl_name.ln_sbd, (x)); } } \
221 while (0)
222 #define gfs2_glock_assert_withdraw(gl, x) do { if (unlikely(!(x))) { \
223 gfs2_dump_glock(NULL, gl, true); \
224 gfs2_assert_withdraw((gl)->gl_name.ln_sbd, (x)); } } \
225 while (0)
226
227 __printf(2, 3)
228 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
229
230 /**
231 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
232 * @gl: the glock
233 * @state: the state we're requesting
234 * @flags: the modifier flags
235 * @gh: the holder structure
236 *
237 * Returns: 0, GLR_*, or errno
238 */
239
gfs2_glock_nq_init(struct gfs2_glock * gl,unsigned int state,u16 flags,struct gfs2_holder * gh)240 static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
241 unsigned int state, u16 flags,
242 struct gfs2_holder *gh)
243 {
244 int error;
245
246 __gfs2_holder_init(gl, state, flags, gh, _RET_IP_);
247
248 error = gfs2_glock_nq(gh);
249 if (error)
250 gfs2_holder_uninit(gh);
251
252 return error;
253 }
254
255 void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
256 void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
257 bool gfs2_queue_try_to_evict(struct gfs2_glock *gl);
258 bool gfs2_queue_verify_delete(struct gfs2_glock *gl, bool later);
259 void gfs2_cancel_delete_work(struct gfs2_glock *gl);
260 void gfs2_flush_delete_work(struct gfs2_sbd *sdp);
261 void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
262 void gfs2_gl_dq_holders(struct gfs2_sbd *sdp);
263 void gfs2_glock_thaw(struct gfs2_sbd *sdp);
264 void gfs2_glock_free(struct gfs2_glock *gl);
265 void gfs2_glock_free_later(struct gfs2_glock *gl);
266
267 int __init gfs2_glock_init(void);
268 void gfs2_glock_exit(void);
269
270 void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
271 void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
272 void gfs2_register_debugfs(void);
273 void gfs2_unregister_debugfs(void);
274
275 void glock_set_object(struct gfs2_glock *gl, void *object);
276 void glock_clear_object(struct gfs2_glock *gl, void *object);
277
278 extern const struct lm_lockops gfs2_dlm_ops;
279
gfs2_holder_mark_uninitialized(struct gfs2_holder * gh)280 static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
281 {
282 gh->gh_gl = NULL;
283 }
284
gfs2_holder_initialized(struct gfs2_holder * gh)285 static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
286 {
287 return gh->gh_gl;
288 }
289
gfs2_holder_queued(struct gfs2_holder * gh)290 static inline bool gfs2_holder_queued(struct gfs2_holder *gh)
291 {
292 return !list_empty(&gh->gh_list);
293 }
294
295 void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation);
296 bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation);
297
glock_needs_demote(struct gfs2_glock * gl)298 static inline bool glock_needs_demote(struct gfs2_glock *gl)
299 {
300 return (test_bit(GLF_DEMOTE, &gl->gl_flags) ||
301 test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags));
302 }
303
304 #endif /* __GLOCK_DOT_H__ */
305