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#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_CANCELED
96 * The lock request was canceled.
97 *
98 */
99
100#define LM_OUT_ST_MASK		0x00000003
101#define LM_OUT_CANCELED		0x00000008
102#define LM_OUT_ERROR		0x00000004
103
104/*
105 * lm_recovery_done() messages
106 */
107
108#define LM_RD_GAVEUP		308
109#define LM_RD_SUCCESS		309
110
111#define GLR_TRYFAILED		13
112
113#define GL_GLOCK_MAX_HOLD        (long)(HZ / 5)
114#define GL_GLOCK_DFT_HOLD        (long)(HZ / 5)
115#define GL_GLOCK_MIN_HOLD        (long)(10)
116#define GL_GLOCK_HOLD_INCR       (long)(HZ / 20)
117#define GL_GLOCK_HOLD_DECR       (long)(HZ / 40)
118
119struct lm_lockops {
120	const char *lm_proto_name;
121	int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
122	void (*lm_first_done) (struct gfs2_sbd *sdp);
123	void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
124				    unsigned int result);
125	void (*lm_unmount) (struct gfs2_sbd *sdp);
126	void (*lm_withdraw) (struct gfs2_sbd *sdp);
127	void (*lm_put_lock) (struct gfs2_glock *gl);
128	int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
129			unsigned int flags);
130	void (*lm_cancel) (struct gfs2_glock *gl);
131	const match_table_t *lm_tokens;
132};
133
134struct gfs2_glock_aspace {
135	struct gfs2_glock glock;
136	struct address_space mapping;
137};
138
139static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
140{
141	struct gfs2_holder *gh;
142	struct pid *pid;
143
144	/* Look in glock's list of holders for one with current task as owner */
145	spin_lock(&gl->gl_lockref.lock);
146	pid = task_pid(current);
147	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
148		if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
149			break;
150		if (gh->gh_owner_pid == pid)
151			goto out;
152	}
153	gh = NULL;
154out:
155	spin_unlock(&gl->gl_lockref.lock);
156
157	return gh;
158}
159
160static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl)
161{
162	if (gl->gl_ops->go_flags & GLOF_ASPACE) {
163		struct gfs2_glock_aspace *gla =
164			container_of(gl, struct gfs2_glock_aspace, glock);
165		return &gla->mapping;
166	}
167	return NULL;
168}
169
170int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
171		   const struct gfs2_glock_operations *glops,
172		   int create, struct gfs2_glock **glp);
173struct gfs2_glock *gfs2_glock_hold(struct gfs2_glock *gl);
174void gfs2_glock_put(struct gfs2_glock *gl);
175void gfs2_glock_queue_put(struct gfs2_glock *gl);
176
177void __gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
178		        u16 flags, struct gfs2_holder *gh,
179		        unsigned long ip);
180static inline void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
181				    u16 flags, struct gfs2_holder *gh) {
182	__gfs2_holder_init(gl, state, flags, gh, _RET_IP_);
183}
184
185void gfs2_holder_reinit(unsigned int state, u16 flags,
186		        struct gfs2_holder *gh);
187void gfs2_holder_uninit(struct gfs2_holder *gh);
188int gfs2_glock_nq(struct gfs2_holder *gh);
189int gfs2_glock_poll(struct gfs2_holder *gh);
190int gfs2_instantiate(struct gfs2_holder *gh);
191int gfs2_glock_holder_ready(struct gfs2_holder *gh);
192int gfs2_glock_wait(struct gfs2_holder *gh);
193int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs);
194void gfs2_glock_dq(struct gfs2_holder *gh);
195void gfs2_glock_dq_wait(struct gfs2_holder *gh);
196void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
197int 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);
201int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
202void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
203void 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
217__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, _RET_IP_);
237
238	error = gfs2_glock_nq(gh);
239	if (error)
240		gfs2_holder_uninit(gh);
241
242	return error;
243}
244
245void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
246void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
247bool gfs2_queue_try_to_evict(struct gfs2_glock *gl);
248void gfs2_cancel_delete_work(struct gfs2_glock *gl);
249void gfs2_flush_delete_work(struct gfs2_sbd *sdp);
250void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
251void gfs2_gl_dq_holders(struct gfs2_sbd *sdp);
252void gfs2_glock_thaw(struct gfs2_sbd *sdp);
253void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
254void gfs2_glock_free(struct gfs2_glock *gl);
255
256int __init gfs2_glock_init(void);
257void gfs2_glock_exit(void);
258
259void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
260void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
261void gfs2_register_debugfs(void);
262void gfs2_unregister_debugfs(void);
263
264void glock_set_object(struct gfs2_glock *gl, void *object);
265void glock_clear_object(struct gfs2_glock *gl, void *object);
266
267extern const struct lm_lockops gfs2_dlm_ops;
268
269static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
270{
271	gh->gh_gl = NULL;
272}
273
274static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
275{
276	return gh->gh_gl;
277}
278
279static inline bool gfs2_holder_queued(struct gfs2_holder *gh)
280{
281	return !list_empty(&gh->gh_list);
282}
283
284void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation);
285bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation);
286
287#endif /* __GLOCK_DOT_H__ */
288