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_RECOVER
62 * GFS sets this flag on lock requests it makes while doing journal recovery.
63 * While ordinary requests are blocked until the end of recovery, requests
64 * with this flag set do proceed.
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 * In addition, when a lock is already held in EX mode locally, a SHARED or
72 * DEFERRED mode request with the LM_FLAG_ANY flag set will be granted.
73 * (The LM_FLAG_ANY flag is only use for SHARED mode requests currently.)
74 *
75 * LM_FLAG_NODE_SCOPE
76 * This holder agrees to share the lock within this node. In other words,
77 * the glock is held in EX mode according to DLM, but local holders on the
78 * same node can share it.
79 */
80
81#define LM_FLAG_TRY 0x0001
82#define LM_FLAG_TRY_1CB 0x0002
83#define LM_FLAG_RECOVER 0x0004
84#define LM_FLAG_ANY 0x0008
85#define LM_FLAG_NODE_SCOPE 0x0020
86#define GL_ASYNC 0x0040
87#define GL_EXACT 0x0080
88#define GL_SKIP 0x0100
89#define GL_NOPID 0x0200
90#define GL_NOCACHE 0x0400
91#define GL_NOBLOCK 0x0800
92
93/*
94 * lm_async_cb return flags
95 *
96 * LM_OUT_ST_MASK
97 * Masks the lower two bits of lock state in the returned value.
98 *
99 * LM_OUT_TRY_AGAIN
100 * The trylock request failed.
101 *
102 * LM_OUT_DEADLOCK
103 * The lock request failed because it would deadlock.
104 *
105 * LM_OUT_CANCELED
106 * The lock request was canceled.
107 *
108 * LM_OUT_ERROR
109 * The lock request timed out or failed.
110 */
111
112#define LM_OUT_ST_MASK 0x00000003
113#define LM_OUT_TRY_AGAIN 0x00000020
114#define LM_OUT_DEADLOCK 0x00000010
115#define LM_OUT_CANCELED 0x00000008
116#define LM_OUT_ERROR 0x00000004
117
118/*
119 * lm_recovery_done() messages
120 */
121
122#define LM_RD_GAVEUP 308
123#define LM_RD_SUCCESS 309
124
125#define GLR_TRYFAILED 13
126
127#define GL_GLOCK_MAX_HOLD (long)(HZ / 5)
128#define GL_GLOCK_DFT_HOLD (long)(HZ / 5)
129#define GL_GLOCK_MIN_HOLD (long)(10)
130#define GL_GLOCK_HOLD_INCR (long)(HZ / 20)
131#define GL_GLOCK_HOLD_DECR (long)(HZ / 40)
132
133struct lm_lockops {
134 const char *lm_proto_name;
135 int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
136 void (*lm_first_done) (struct gfs2_sbd *sdp);
137 void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
138 unsigned int result);
139 void (*lm_unmount) (struct gfs2_sbd *sdp, bool clean);
140 void (*lm_withdraw) (struct gfs2_sbd *sdp);
141 void (*lm_put_lock) (struct gfs2_glock *gl);
142 int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
143 unsigned int flags);
144 void (*lm_cancel) (struct gfs2_glock *gl);
145 const match_table_t *lm_tokens;
146};
147
148struct gfs2_glock_aspace {
149 struct gfs2_glock glock;
150 struct address_space mapping;
151};
152
153static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
154{
155 struct gfs2_holder *gh;
156 struct pid *pid;
157
158 /* Look in glock's list of holders for one with current task as owner */
159 spin_lock(lock: &gl->gl_lockref.lock);
160 pid = task_pid(current);
161 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
162 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
163 break;
164 if (gh->gh_owner_pid == pid)
165 goto out;
166 }
167 gh = NULL;
168out:
169 spin_unlock(lock: &gl->gl_lockref.lock);
170
171 return gh;
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
184int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
185 const struct gfs2_glock_operations *glops,
186 int create, struct gfs2_glock **glp);
187struct gfs2_glock *gfs2_glock_hold(struct gfs2_glock *gl);
188void gfs2_glock_put(struct gfs2_glock *gl);
189void gfs2_glock_put_async(struct gfs2_glock *gl);
190
191void __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
199void gfs2_holder_reinit(unsigned int state, u16 flags,
200 struct gfs2_holder *gh);
201void gfs2_holder_uninit(struct gfs2_holder *gh);
202int gfs2_glock_nq(struct gfs2_holder *gh);
203int gfs2_glock_poll(struct gfs2_holder *gh);
204int gfs2_instantiate(struct gfs2_holder *gh);
205int gfs2_glock_holder_ready(struct gfs2_holder *gh);
206int gfs2_glock_wait(struct gfs2_holder *gh);
207int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs);
208void gfs2_glock_dq(struct gfs2_holder *gh);
209void gfs2_glock_dq_wait(struct gfs2_holder *gh);
210void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
211int 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);
215int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
216void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
217void 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
231__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
259void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
260void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
261bool gfs2_queue_try_to_evict(struct gfs2_glock *gl);
262bool gfs2_queue_verify_delete(struct gfs2_glock *gl, bool later);
263void gfs2_cancel_delete_work(struct gfs2_glock *gl);
264void gfs2_flush_delete_work(struct gfs2_sbd *sdp);
265void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
266void gfs2_withdraw_glocks(struct gfs2_sbd *sdp);
267void gfs2_glock_thaw(struct gfs2_sbd *sdp);
268void gfs2_glock_free(struct gfs2_glock *gl);
269void gfs2_glock_free_later(struct gfs2_glock *gl);
270
271int __init gfs2_glock_init(void);
272void gfs2_glock_exit(void);
273
274void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
275void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
276void gfs2_register_debugfs(void);
277void gfs2_unregister_debugfs(void);
278
279void glock_set_object(struct gfs2_glock *gl, void *object);
280void glock_clear_object(struct gfs2_glock *gl, void *object);
281
282extern const struct lm_lockops gfs2_dlm_ops;
283
284static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
285{
286 gh->gh_gl = NULL;
287}
288
289static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
290{
291 return gh->gh_gl;
292}
293
294static inline bool gfs2_holder_queued(struct gfs2_holder *gh)
295{
296 return !list_empty(head: &gh->gh_list);
297}
298
299void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation);
300bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation);
301
302static inline bool glock_needs_demote(struct gfs2_glock *gl)
303{
304 return (test_bit(GLF_DEMOTE, &gl->gl_flags) ||
305 test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags));
306}
307
308#endif /* __GLOCK_DOT_H__ */
309

source code of linux/fs/gfs2/glock.h