xref: /kernel/linux/linux-6.6/fs/gfs2/glock.h (revision 62306a36)
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_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
88/*
89 * lm_async_cb return flags
90 *
91 * LM_OUT_ST_MASK
92 * Masks the lower two bits of lock state in the returned value.
93 *
94 * LM_OUT_CANCELED
95 * The lock request was canceled.
96 *
97 */
98
99#define LM_OUT_ST_MASK		0x00000003
100#define LM_OUT_CANCELED		0x00000008
101#define LM_OUT_ERROR		0x00000004
102
103/*
104 * lm_recovery_done() messages
105 */
106
107#define LM_RD_GAVEUP		308
108#define LM_RD_SUCCESS		309
109
110#define GLR_TRYFAILED		13
111
112#define GL_GLOCK_MAX_HOLD        (long)(HZ / 5)
113#define GL_GLOCK_DFT_HOLD        (long)(HZ / 5)
114#define GL_GLOCK_MIN_HOLD        (long)(10)
115#define GL_GLOCK_HOLD_INCR       (long)(HZ / 20)
116#define GL_GLOCK_HOLD_DECR       (long)(HZ / 40)
117
118struct lm_lockops {
119	const char *lm_proto_name;
120	int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
121	void (*lm_first_done) (struct gfs2_sbd *sdp);
122	void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
123				    unsigned int result);
124	void (*lm_unmount) (struct gfs2_sbd *sdp);
125	void (*lm_withdraw) (struct gfs2_sbd *sdp);
126	void (*lm_put_lock) (struct gfs2_glock *gl);
127	int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
128			unsigned int flags);
129	void (*lm_cancel) (struct gfs2_glock *gl);
130	const match_table_t *lm_tokens;
131};
132
133struct gfs2_glock_aspace {
134	struct gfs2_glock glock;
135	struct address_space mapping;
136};
137
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_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;
153out:
154	spin_unlock(&gl->gl_lockref.lock);
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		struct gfs2_glock_aspace *gla =
178			container_of(gl, struct gfs2_glock_aspace, glock);
179		return &gla->mapping;
180	}
181	return NULL;
182}
183
184extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
185			  const struct gfs2_glock_operations *glops,
186			  int create, struct gfs2_glock **glp);
187extern struct gfs2_glock *gfs2_glock_hold(struct gfs2_glock *gl);
188extern void gfs2_glock_put(struct gfs2_glock *gl);
189extern void gfs2_glock_queue_put(struct gfs2_glock *gl);
190
191extern void __gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
192			       u16 flags, struct gfs2_holder *gh,
193			       unsigned long ip);
194static inline void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
195				    u16 flags, struct gfs2_holder *gh) {
196	__gfs2_holder_init(gl, state, flags, gh, _RET_IP_);
197}
198
199extern void gfs2_holder_reinit(unsigned int state, u16 flags,
200			       struct gfs2_holder *gh);
201extern void gfs2_holder_uninit(struct gfs2_holder *gh);
202extern int gfs2_glock_nq(struct gfs2_holder *gh);
203extern int gfs2_glock_poll(struct gfs2_holder *gh);
204extern int gfs2_instantiate(struct gfs2_holder *gh);
205extern int gfs2_glock_holder_ready(struct gfs2_holder *gh);
206extern int gfs2_glock_wait(struct gfs2_holder *gh);
207extern int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs);
208extern void gfs2_glock_dq(struct gfs2_holder *gh);
209extern void gfs2_glock_dq_wait(struct gfs2_holder *gh);
210extern void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
211extern int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
212			     const struct gfs2_glock_operations *glops,
213			     unsigned int state, u16 flags,
214			     struct gfs2_holder *gh);
215extern int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
216extern void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
217extern void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl,
218			    bool fsid);
219#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) {		\
220			gfs2_dump_glock(NULL, gl, true);	\
221			BUG(); } } while(0)
222#define gfs2_glock_assert_warn(gl, x) do { if (unlikely(!(x))) {	\
223			gfs2_dump_glock(NULL, gl, true);		\
224			gfs2_assert_warn((gl)->gl_name.ln_sbd, (x)); } } \
225	while (0)
226#define gfs2_glock_assert_withdraw(gl, x) do { if (unlikely(!(x))) {	\
227			gfs2_dump_glock(NULL, gl, true);		\
228			gfs2_assert_withdraw((gl)->gl_name.ln_sbd, (x)); } } \
229	while (0)
230
231extern __printf(2, 3)
232void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
233
234/**
235 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
236 * @gl: the glock
237 * @state: the state we're requesting
238 * @flags: the modifier flags
239 * @gh: the holder structure
240 *
241 * Returns: 0, GLR_*, or errno
242 */
243
244static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
245				     unsigned int state, u16 flags,
246				     struct gfs2_holder *gh)
247{
248	int error;
249
250	__gfs2_holder_init(gl, state, flags, gh, _RET_IP_);
251
252	error = gfs2_glock_nq(gh);
253	if (error)
254		gfs2_holder_uninit(gh);
255
256	return error;
257}
258
259extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
260extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
261extern bool gfs2_queue_try_to_evict(struct gfs2_glock *gl);
262extern void gfs2_cancel_delete_work(struct gfs2_glock *gl);
263extern void gfs2_flush_delete_work(struct gfs2_sbd *sdp);
264extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
265extern void gfs2_gl_dq_holders(struct gfs2_sbd *sdp);
266extern void gfs2_glock_thaw(struct gfs2_sbd *sdp);
267extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
268extern void gfs2_glock_free(struct gfs2_glock *gl);
269
270extern int __init gfs2_glock_init(void);
271extern void gfs2_glock_exit(void);
272
273extern void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
274extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
275extern void gfs2_register_debugfs(void);
276extern void gfs2_unregister_debugfs(void);
277
278extern void glock_set_object(struct gfs2_glock *gl, void *object);
279extern void glock_clear_object(struct gfs2_glock *gl, void *object);
280
281extern const struct lm_lockops gfs2_dlm_ops;
282
283static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
284{
285	gh->gh_gl = NULL;
286}
287
288static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
289{
290	return gh->gh_gl;
291}
292
293static inline bool gfs2_holder_queued(struct gfs2_holder *gh)
294{
295	return !list_empty(&gh->gh_list);
296}
297
298extern void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation);
299extern bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation);
300
301#endif /* __GLOCK_DOT_H__ */
302