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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
19enum {
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 0x00000001
83#define LM_FLAG_TRY_1CB 0x00000002
84#define LM_FLAG_NOEXP 0x00000004
85#define LM_FLAG_ANY 0x00000008
86#define LM_FLAG_PRIORITY 0x00000010
87#define GL_ASYNC 0x00000040
88#define GL_EXACT 0x00000080
89#define GL_SKIP 0x00000100
90#define GL_NOCACHE 0x00000400
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
122struct 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
137extern struct workqueue_struct *gfs2_delete_workqueue;
138static 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_spin);
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;
153out:
154 spin_unlock(&gl->gl_spin);
155
156 return gh;
157}
158
159static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
160{
161 return gl->gl_state == LM_ST_EXCLUSIVE;
162}
163
164static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
165{
166 return gl->gl_state == LM_ST_DEFERRED;
167}
168
169static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
170{
171 return gl->gl_state == LM_ST_SHARED;
172}
173
174static 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
181int gfs2_glock_get(struct gfs2_sbd *sdp,
182 u64 number, const struct gfs2_glock_operations *glops,
183 int create, struct gfs2_glock **glp);
184void gfs2_glock_hold(struct gfs2_glock *gl);
185void gfs2_glock_put_nolock(struct gfs2_glock *gl);
186void gfs2_glock_put(struct gfs2_glock *gl);
187void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
188 struct gfs2_holder *gh);
189void gfs2_holder_reinit(unsigned int state, unsigned flags,
190 struct gfs2_holder *gh);
191void gfs2_holder_uninit(struct gfs2_holder *gh);
192int gfs2_glock_nq(struct gfs2_holder *gh);
193int gfs2_glock_poll(struct gfs2_holder *gh);
194int gfs2_glock_wait(struct gfs2_holder *gh);
195void gfs2_glock_dq(struct gfs2_holder *gh);
196void gfs2_glock_dq_wait(struct gfs2_holder *gh);
197
198void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
199int gfs2_glock_nq_num(struct gfs2_sbd *sdp,
200 u64 number, const struct gfs2_glock_operations *glops,
201 unsigned int state, int flags, struct gfs2_holder *gh);
202
203int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
204void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
205void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs);
206
207__printf(2, 3)
208void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
209
210/**
211 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
212 * @gl: the glock
213 * @state: the state we're requesting
214 * @flags: the modifier flags
215 * @gh: the holder structure
216 *
217 * Returns: 0, GLR_*, or errno
218 */
219
220static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
221 unsigned int state, int flags,
222 struct gfs2_holder *gh)
223{
224 int error;
225
226 gfs2_holder_init(gl, state, flags, gh);
227
228 error = gfs2_glock_nq(gh);
229 if (error)
230 gfs2_holder_uninit(gh);
231
232 return error;
233}
234
235extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
236extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
237extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
238extern void gfs2_glock_finish_truncate(struct gfs2_inode *ip);
239extern void gfs2_glock_thaw(struct gfs2_sbd *sdp);
240extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
241extern void gfs2_glock_free(struct gfs2_glock *gl);
242
243extern int __init gfs2_glock_init(void);
244extern void gfs2_glock_exit(void);
245
246extern int gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
247extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
248extern int gfs2_register_debugfs(void);
249extern void gfs2_unregister_debugfs(void);
250
251extern const struct lm_lockops gfs2_dlm_ops;
252
253#endif /* __GLOCK_DOT_H__ */
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
17enum {
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_PRIORITY
72 * Override fairness considerations. Suppose a lock is held in a shared state
73 * and there is a pending request for the deferred state. A shared lock
74 * request with the priority flag would be allowed to bypass the deferred
75 * request and directly join the other shared lock. A shared lock request
76 * without the priority flag might be forced to wait until the deferred
77 * requested had acquired and released the lock.
78 */
79
80#define LM_FLAG_TRY 0x0001
81#define LM_FLAG_TRY_1CB 0x0002
82#define LM_FLAG_NOEXP 0x0004
83#define LM_FLAG_ANY 0x0008
84#define LM_FLAG_PRIORITY 0x0010
85#define GL_ASYNC 0x0040
86#define GL_EXACT 0x0080
87#define GL_SKIP 0x0100
88#define GL_NOCACHE 0x0400
89
90/*
91 * lm_async_cb return flags
92 *
93 * LM_OUT_ST_MASK
94 * Masks the lower two bits of lock state in the returned value.
95 *
96 * LM_OUT_CANCELED
97 * The lock request was canceled.
98 *
99 */
100
101#define LM_OUT_ST_MASK 0x00000003
102#define LM_OUT_CANCELED 0x00000008
103#define LM_OUT_ERROR 0x00000004
104
105/*
106 * lm_recovery_done() messages
107 */
108
109#define LM_RD_GAVEUP 308
110#define LM_RD_SUCCESS 309
111
112#define GLR_TRYFAILED 13
113
114#define GL_GLOCK_MAX_HOLD (long)(HZ / 5)
115#define GL_GLOCK_DFT_HOLD (long)(HZ / 5)
116#define GL_GLOCK_MIN_HOLD (long)(10)
117#define GL_GLOCK_HOLD_INCR (long)(HZ / 20)
118#define GL_GLOCK_HOLD_DECR (long)(HZ / 40)
119
120struct lm_lockops {
121 const char *lm_proto_name;
122 int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
123 void (*lm_first_done) (struct gfs2_sbd *sdp);
124 void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
125 unsigned int result);
126 void (*lm_unmount) (struct gfs2_sbd *sdp);
127 void (*lm_withdraw) (struct gfs2_sbd *sdp);
128 void (*lm_put_lock) (struct gfs2_glock *gl);
129 int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
130 unsigned int flags);
131 void (*lm_cancel) (struct gfs2_glock *gl);
132 const match_table_t *lm_tokens;
133};
134
135extern struct workqueue_struct *gfs2_delete_workqueue;
136static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
137{
138 struct gfs2_holder *gh;
139 struct pid *pid;
140
141 /* Look in glock's list of holders for one with current task as owner */
142 spin_lock(&gl->gl_lockref.lock);
143 pid = task_pid(current);
144 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
145 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
146 break;
147 if (gh->gh_owner_pid == pid)
148 goto out;
149 }
150 gh = NULL;
151out:
152 spin_unlock(&gl->gl_lockref.lock);
153
154 return gh;
155}
156
157static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
158{
159 return gl->gl_state == LM_ST_EXCLUSIVE;
160}
161
162static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
163{
164 return gl->gl_state == LM_ST_DEFERRED;
165}
166
167static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
168{
169 return gl->gl_state == LM_ST_SHARED;
170}
171
172static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl)
173{
174 if (gl->gl_ops->go_flags & GLOF_ASPACE)
175 return (struct address_space *)(gl + 1);
176 return NULL;
177}
178
179extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
180 const struct gfs2_glock_operations *glops,
181 int create, struct gfs2_glock **glp);
182extern void gfs2_glock_hold(struct gfs2_glock *gl);
183extern void gfs2_glock_put(struct gfs2_glock *gl);
184extern void gfs2_glock_queue_put(struct gfs2_glock *gl);
185extern void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
186 u16 flags, struct gfs2_holder *gh);
187extern void gfs2_holder_reinit(unsigned int state, u16 flags,
188 struct gfs2_holder *gh);
189extern void gfs2_holder_uninit(struct gfs2_holder *gh);
190extern int gfs2_glock_nq(struct gfs2_holder *gh);
191extern int gfs2_glock_poll(struct gfs2_holder *gh);
192extern int gfs2_glock_wait(struct gfs2_holder *gh);
193extern int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs);
194extern void gfs2_glock_dq(struct gfs2_holder *gh);
195extern void gfs2_glock_dq_wait(struct gfs2_holder *gh);
196extern void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
197extern int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
198 const struct gfs2_glock_operations *glops,
199 unsigned int state, u16 flags,
200 struct gfs2_holder *gh);
201extern int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
202extern void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
203extern void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl,
204 bool fsid);
205#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { \
206 gfs2_dump_glock(NULL, gl, true); \
207 BUG(); } } while(0)
208#define gfs2_glock_assert_warn(gl, x) do { if (unlikely(!(x))) { \
209 gfs2_dump_glock(NULL, gl, true); \
210 gfs2_assert_warn((gl)->gl_name.ln_sbd, (x)); } } \
211 while (0)
212#define gfs2_glock_assert_withdraw(gl, x) do { if (unlikely(!(x))) { \
213 gfs2_dump_glock(NULL, gl, true); \
214 gfs2_assert_withdraw((gl)->gl_name.ln_sbd, (x)); } } \
215 while (0)
216
217extern __printf(2, 3)
218void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
219
220/**
221 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
222 * @gl: the glock
223 * @state: the state we're requesting
224 * @flags: the modifier flags
225 * @gh: the holder structure
226 *
227 * Returns: 0, GLR_*, or errno
228 */
229
230static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
231 unsigned int state, u16 flags,
232 struct gfs2_holder *gh)
233{
234 int error;
235
236 gfs2_holder_init(gl, state, flags, gh);
237
238 error = gfs2_glock_nq(gh);
239 if (error)
240 gfs2_holder_uninit(gh);
241
242 return error;
243}
244
245extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
246extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
247extern bool gfs2_queue_delete_work(struct gfs2_glock *gl, unsigned long delay);
248extern void gfs2_cancel_delete_work(struct gfs2_glock *gl);
249extern bool gfs2_delete_work_queued(const struct gfs2_glock *gl);
250extern void gfs2_flush_delete_work(struct gfs2_sbd *sdp);
251extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
252extern void gfs2_glock_finish_truncate(struct gfs2_inode *ip);
253extern void gfs2_glock_thaw(struct gfs2_sbd *sdp);
254extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
255extern void gfs2_glock_free(struct gfs2_glock *gl);
256
257extern int __init gfs2_glock_init(void);
258extern void gfs2_glock_exit(void);
259
260extern void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
261extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
262extern void gfs2_register_debugfs(void);
263extern void gfs2_unregister_debugfs(void);
264
265extern const struct lm_lockops gfs2_dlm_ops;
266
267static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
268{
269 gh->gh_gl = NULL;
270}
271
272static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
273{
274 return gh->gh_gl;
275}
276
277static inline bool gfs2_holder_queued(struct gfs2_holder *gh)
278{
279 return !list_empty(&gh->gh_list);
280}
281
282/**
283 * glock_set_object - set the gl_object field of a glock
284 * @gl: the glock
285 * @object: the object
286 */
287static inline void glock_set_object(struct gfs2_glock *gl, void *object)
288{
289 spin_lock(&gl->gl_lockref.lock);
290 if (gfs2_assert_warn(gl->gl_name.ln_sbd, gl->gl_object == NULL))
291 gfs2_dump_glock(NULL, gl, true);
292 gl->gl_object = object;
293 spin_unlock(&gl->gl_lockref.lock);
294}
295
296/**
297 * glock_clear_object - clear the gl_object field of a glock
298 * @gl: the glock
299 * @object: the object
300 *
301 * I'd love to similarly add this:
302 * else if (gfs2_assert_warn(gl->gl_sbd, gl->gl_object == object))
303 * gfs2_dump_glock(NULL, gl, true);
304 * Unfortunately, that's not possible because as soon as gfs2_delete_inode
305 * frees the block in the rgrp, another process can reassign it for an I_NEW
306 * inode in gfs2_create_inode because that calls new_inode, not gfs2_iget.
307 * That means gfs2_delete_inode may subsequently try to call this function
308 * for a glock that's already pointing to a brand new inode. If we clear the
309 * new inode's gl_object, we'll introduce metadata corruption. Function
310 * gfs2_delete_inode calls clear_inode which calls gfs2_clear_inode which also
311 * tries to clear gl_object, so it's more than just gfs2_delete_inode.
312 *
313 */
314static inline void glock_clear_object(struct gfs2_glock *gl, void *object)
315{
316 spin_lock(&gl->gl_lockref.lock);
317 if (gl->gl_object == object)
318 gl->gl_object = NULL;
319 spin_unlock(&gl->gl_lockref.lock);
320}
321
322extern void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation);
323extern bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation);
324
325#endif /* __GLOCK_DOT_H__ */