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 19 enum { 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) 121 122 struct lm_lockops { 123 const char *lm_proto_name; 124 int (*lm_mount) (struct gfs2_sbd *sdp, const char *fsname); 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 }; 133 134 extern struct workqueue_struct *gfs2_delete_workqueue; 135 static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl) 136 { 137 struct gfs2_holder *gh; 138 struct pid *pid; 139 140 /* Look in glock's list of holders for one with current task as owner */ 141 spin_lock(&gl->gl_spin); 142 pid = task_pid(current); 143 list_for_each_entry(gh, &gl->gl_holders, gh_list) { 144 if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) 145 break; 146 if (gh->gh_owner_pid == pid) 147 goto out; 148 } 149 gh = NULL; 150 out: 151 spin_unlock(&gl->gl_spin); 152 153 return gh; 154 } 155 156 static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl) 157 { 158 return gl->gl_state == LM_ST_EXCLUSIVE; 159 } 160 161 static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl) 162 { 163 return gl->gl_state == LM_ST_DEFERRED; 164 } 165 166 static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl) 167 { 168 return gl->gl_state == LM_ST_SHARED; 169 } 170 171 static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl) 172 { 173 if (gl->gl_ops->go_flags & GLOF_ASPACE) 174 return (struct address_space *)(gl + 1); 175 return NULL; 176 } 177 178 int gfs2_glock_get(struct gfs2_sbd *sdp, 179 u64 number, const struct gfs2_glock_operations *glops, 180 int create, struct gfs2_glock **glp); 181 void gfs2_glock_hold(struct gfs2_glock *gl); 182 void gfs2_glock_put_nolock(struct gfs2_glock *gl); 183 void gfs2_glock_put(struct gfs2_glock *gl); 184 void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, 185 struct gfs2_holder *gh); 186 void gfs2_holder_reinit(unsigned int state, unsigned flags, 187 struct gfs2_holder *gh); 188 void gfs2_holder_uninit(struct gfs2_holder *gh); 189 int gfs2_glock_nq(struct gfs2_holder *gh); 190 int gfs2_glock_poll(struct gfs2_holder *gh); 191 int gfs2_glock_wait(struct gfs2_holder *gh); 192 void gfs2_glock_dq(struct gfs2_holder *gh); 193 void gfs2_glock_dq_wait(struct gfs2_holder *gh); 194 195 void gfs2_glock_dq_uninit(struct gfs2_holder *gh); 196 int gfs2_glock_nq_num(struct gfs2_sbd *sdp, 197 u64 number, const struct gfs2_glock_operations *glops, 198 unsigned int state, int flags, struct gfs2_holder *gh); 199 200 int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs); 201 void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs); 202 void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs); 203 204 __attribute__ ((format(printf, 2, 3))) 205 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...); 206 207 /** 208 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock 209 * @gl: the glock 210 * @state: the state we're requesting 211 * @flags: the modifier flags 212 * @gh: the holder structure 213 * 214 * Returns: 0, GLR_*, or errno 215 */ 216 217 static inline int gfs2_glock_nq_init(struct gfs2_glock *gl, 218 unsigned int state, int flags, 219 struct gfs2_holder *gh) 220 { 221 int error; 222 223 gfs2_holder_init(gl, state, flags, gh); 224 225 error = gfs2_glock_nq(gh); 226 if (error) 227 gfs2_holder_uninit(gh); 228 229 return error; 230 } 231 232 extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state); 233 extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret); 234 extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp); 235 extern void gfs2_glock_finish_truncate(struct gfs2_inode *ip); 236 extern void gfs2_glock_thaw(struct gfs2_sbd *sdp); 237 extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl); 238 extern void gfs2_glock_free(struct gfs2_glock *gl); 239 240 extern int __init gfs2_glock_init(void); 241 extern void gfs2_glock_exit(void); 242 243 extern int gfs2_create_debugfs_file(struct gfs2_sbd *sdp); 244 extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp); 245 extern int gfs2_register_debugfs(void); 246 extern void gfs2_unregister_debugfs(void); 247 248 extern const struct lm_lockops gfs2_dlm_ops; 249 250 #endif /* __GLOCK_DOT_H__ */ 251