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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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 * LM_FLAG_NODE_SCOPE
80 * This holder agrees to share the lock within this node. In other words,
81 * the glock is held in EX mode according to DLM, but local holders on the
82 * same node can share it.
83 */
84
85#define LM_FLAG_TRY 0x0001
86#define LM_FLAG_TRY_1CB 0x0002
87#define LM_FLAG_NOEXP 0x0004
88#define LM_FLAG_ANY 0x0008
89#define LM_FLAG_PRIORITY 0x0010
90#define LM_FLAG_NODE_SCOPE 0x0020
91#define GL_ASYNC 0x0040
92#define GL_EXACT 0x0080
93#define GL_SKIP 0x0100
94#define GL_NOPID 0x0200
95#define GL_NOCACHE 0x0400
96
97/*
98 * lm_async_cb return flags
99 *
100 * LM_OUT_ST_MASK
101 * Masks the lower two bits of lock state in the returned value.
102 *
103 * LM_OUT_CANCELED
104 * The lock request was canceled.
105 *
106 */
107
108#define LM_OUT_ST_MASK 0x00000003
109#define LM_OUT_CANCELED 0x00000008
110#define LM_OUT_ERROR 0x00000004
111
112/*
113 * lm_recovery_done() messages
114 */
115
116#define LM_RD_GAVEUP 308
117#define LM_RD_SUCCESS 309
118
119#define GLR_TRYFAILED 13
120
121#define GL_GLOCK_MAX_HOLD (long)(HZ / 5)
122#define GL_GLOCK_DFT_HOLD (long)(HZ / 5)
123#define GL_GLOCK_MIN_HOLD (long)(10)
124#define GL_GLOCK_HOLD_INCR (long)(HZ / 20)
125#define GL_GLOCK_HOLD_DECR (long)(HZ / 40)
126
127struct lm_lockops {
128 const char *lm_proto_name;
129 int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
130 void (*lm_first_done) (struct gfs2_sbd *sdp);
131 void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
132 unsigned int result);
133 void (*lm_unmount) (struct gfs2_sbd *sdp);
134 void (*lm_withdraw) (struct gfs2_sbd *sdp);
135 void (*lm_put_lock) (struct gfs2_glock *gl);
136 int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
137 unsigned int flags);
138 void (*lm_cancel) (struct gfs2_glock *gl);
139 const match_table_t *lm_tokens;
140};
141
142struct gfs2_glock_aspace {
143 struct gfs2_glock glock;
144 struct address_space mapping;
145};
146
147static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
148{
149 struct gfs2_holder *gh;
150 struct pid *pid;
151
152 /* Look in glock's list of holders for one with current task as owner */
153 spin_lock(&gl->gl_lockref.lock);
154 pid = task_pid(current);
155 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
156 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
157 break;
158 if (gh->gh_owner_pid == pid)
159 goto out;
160 }
161 gh = NULL;
162out:
163 spin_unlock(&gl->gl_lockref.lock);
164
165 return gh;
166}
167
168static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
169{
170 return gl->gl_state == LM_ST_EXCLUSIVE;
171}
172
173static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
174{
175 return gl->gl_state == LM_ST_DEFERRED;
176}
177
178static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
179{
180 return gl->gl_state == LM_ST_SHARED;
181}
182
183static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl)
184{
185 if (gl->gl_ops->go_flags & GLOF_ASPACE) {
186 struct gfs2_glock_aspace *gla =
187 container_of(gl, struct gfs2_glock_aspace, glock);
188 return &gla->mapping;
189 }
190 return NULL;
191}
192
193extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
194 const struct gfs2_glock_operations *glops,
195 int create, struct gfs2_glock **glp);
196extern struct gfs2_glock *gfs2_glock_hold(struct gfs2_glock *gl);
197extern void gfs2_glock_put(struct gfs2_glock *gl);
198extern void gfs2_glock_queue_put(struct gfs2_glock *gl);
199
200extern void __gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
201 u16 flags, struct gfs2_holder *gh,
202 unsigned long ip);
203static inline void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
204 u16 flags, struct gfs2_holder *gh) {
205 __gfs2_holder_init(gl, state, flags, gh, _RET_IP_);
206}
207
208extern void gfs2_holder_reinit(unsigned int state, u16 flags,
209 struct gfs2_holder *gh);
210extern void gfs2_holder_uninit(struct gfs2_holder *gh);
211extern int gfs2_glock_nq(struct gfs2_holder *gh);
212extern int gfs2_glock_poll(struct gfs2_holder *gh);
213extern int gfs2_instantiate(struct gfs2_holder *gh);
214extern int gfs2_glock_holder_ready(struct gfs2_holder *gh);
215extern int gfs2_glock_wait(struct gfs2_holder *gh);
216extern int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs);
217extern void gfs2_glock_dq(struct gfs2_holder *gh);
218extern void gfs2_glock_dq_wait(struct gfs2_holder *gh);
219extern void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
220extern int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
221 const struct gfs2_glock_operations *glops,
222 unsigned int state, u16 flags,
223 struct gfs2_holder *gh);
224extern int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
225extern void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
226extern void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl,
227 bool fsid);
228#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { \
229 gfs2_dump_glock(NULL, gl, true); \
230 BUG(); } } while(0)
231#define gfs2_glock_assert_warn(gl, x) do { if (unlikely(!(x))) { \
232 gfs2_dump_glock(NULL, gl, true); \
233 gfs2_assert_warn((gl)->gl_name.ln_sbd, (x)); } } \
234 while (0)
235#define gfs2_glock_assert_withdraw(gl, x) do { if (unlikely(!(x))) { \
236 gfs2_dump_glock(NULL, gl, true); \
237 gfs2_assert_withdraw((gl)->gl_name.ln_sbd, (x)); } } \
238 while (0)
239
240extern __printf(2, 3)
241void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
242
243/**
244 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
245 * @gl: the glock
246 * @state: the state we're requesting
247 * @flags: the modifier flags
248 * @gh: the holder structure
249 *
250 * Returns: 0, GLR_*, or errno
251 */
252
253static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
254 unsigned int state, u16 flags,
255 struct gfs2_holder *gh)
256{
257 int error;
258
259 __gfs2_holder_init(gl, state, flags, gh, _RET_IP_);
260
261 error = gfs2_glock_nq(gh);
262 if (error)
263 gfs2_holder_uninit(gh);
264
265 return error;
266}
267
268extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
269extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
270extern bool gfs2_queue_try_to_evict(struct gfs2_glock *gl);
271extern void gfs2_cancel_delete_work(struct gfs2_glock *gl);
272extern void gfs2_flush_delete_work(struct gfs2_sbd *sdp);
273extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
274extern void gfs2_gl_dq_holders(struct gfs2_sbd *sdp);
275extern void gfs2_glock_thaw(struct gfs2_sbd *sdp);
276extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
277extern void gfs2_glock_free(struct gfs2_glock *gl);
278
279extern int __init gfs2_glock_init(void);
280extern void gfs2_glock_exit(void);
281
282extern void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
283extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
284extern void gfs2_register_debugfs(void);
285extern void gfs2_unregister_debugfs(void);
286
287extern void glock_set_object(struct gfs2_glock *gl, void *object);
288extern void glock_clear_object(struct gfs2_glock *gl, void *object);
289
290extern const struct lm_lockops gfs2_dlm_ops;
291
292static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
293{
294 gh->gh_gl = NULL;
295}
296
297static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
298{
299 return gh->gh_gl;
300}
301
302static inline bool gfs2_holder_queued(struct gfs2_holder *gh)
303{
304 return !list_empty(&gh->gh_list);
305}
306
307extern void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation);
308extern bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation);
309
310#endif /* __GLOCK_DOT_H__ */