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_ATIME 0x00000200 91 #define GL_NOCACHE 0x00000400 92 93 /* 94 * lm_lock() and 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_CANCELED 100 * The lock request was canceled. 101 * 102 * LM_OUT_ASYNC 103 * The result of the request will be returned in an LM_CB_ASYNC callback. 104 * 105 */ 106 107 #define LM_OUT_ST_MASK 0x00000003 108 #define LM_OUT_CANCELED 0x00000008 109 #define LM_OUT_ASYNC 0x00000080 110 #define LM_OUT_ERROR 0x00000100 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 struct lm_lockops { 122 const char *lm_proto_name; 123 int (*lm_mount) (struct gfs2_sbd *sdp, const char *fsname); 124 void (*lm_unmount) (struct gfs2_sbd *sdp); 125 void (*lm_withdraw) (struct gfs2_sbd *sdp); 126 void (*lm_put_lock) (struct kmem_cache *cachep, struct gfs2_glock *gl); 127 unsigned int (*lm_lock) (struct gfs2_glock *gl, 128 unsigned int req_state, unsigned int flags); 129 void (*lm_cancel) (struct gfs2_glock *gl); 130 const match_table_t *lm_tokens; 131 }; 132 133 #define LM_FLAG_TRY 0x00000001 134 #define LM_FLAG_TRY_1CB 0x00000002 135 #define LM_FLAG_NOEXP 0x00000004 136 #define LM_FLAG_ANY 0x00000008 137 #define LM_FLAG_PRIORITY 0x00000010 138 139 #define GL_ASYNC 0x00000040 140 #define GL_EXACT 0x00000080 141 #define GL_SKIP 0x00000100 142 #define GL_NOCACHE 0x00000400 143 144 #define GLR_TRYFAILED 13 145 146 extern struct workqueue_struct *gfs2_delete_workqueue; 147 static 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_spin); 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; 162 out: 163 spin_unlock(&gl->gl_spin); 164 165 return gh; 166 } 167 168 static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl) 169 { 170 return gl->gl_state == LM_ST_EXCLUSIVE; 171 } 172 173 static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl) 174 { 175 return gl->gl_state == LM_ST_DEFERRED; 176 } 177 178 static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl) 179 { 180 return gl->gl_state == LM_ST_SHARED; 181 } 182 183 int gfs2_glock_get(struct gfs2_sbd *sdp, 184 u64 number, const struct gfs2_glock_operations *glops, 185 int create, struct gfs2_glock **glp); 186 void gfs2_glock_hold(struct gfs2_glock *gl); 187 void gfs2_glock_put_nolock(struct gfs2_glock *gl); 188 int gfs2_glock_put(struct gfs2_glock *gl); 189 void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, 190 struct gfs2_holder *gh); 191 void gfs2_holder_reinit(unsigned int state, unsigned flags, 192 struct gfs2_holder *gh); 193 void gfs2_holder_uninit(struct gfs2_holder *gh); 194 int gfs2_glock_nq(struct gfs2_holder *gh); 195 int gfs2_glock_poll(struct gfs2_holder *gh); 196 int gfs2_glock_wait(struct gfs2_holder *gh); 197 void gfs2_glock_dq(struct gfs2_holder *gh); 198 void gfs2_glock_dq_wait(struct gfs2_holder *gh); 199 200 void gfs2_glock_dq_uninit(struct gfs2_holder *gh); 201 int gfs2_glock_nq_num(struct gfs2_sbd *sdp, 202 u64 number, const struct gfs2_glock_operations *glops, 203 unsigned int state, int flags, struct gfs2_holder *gh); 204 205 int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs); 206 void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs); 207 void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs); 208 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...); 209 210 /** 211 * gfs2_glock_nq_init - intialize a holder and enqueue it on a glock 212 * @gl: the glock 213 * @state: the state we're requesting 214 * @flags: the modifier flags 215 * @gh: the holder structure 216 * 217 * Returns: 0, GLR_*, or errno 218 */ 219 220 static inline int gfs2_glock_nq_init(struct gfs2_glock *gl, 221 unsigned int state, int flags, 222 struct gfs2_holder *gh) 223 { 224 int error; 225 226 gfs2_holder_init(gl, state, flags, gh); 227 228 error = gfs2_glock_nq(gh); 229 if (error) 230 gfs2_holder_uninit(gh); 231 232 return error; 233 } 234 235 /* Lock Value Block functions */ 236 237 int gfs2_lvb_hold(struct gfs2_glock *gl); 238 void gfs2_lvb_unhold(struct gfs2_glock *gl); 239 240 void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state); 241 void gfs2_glock_complete(struct gfs2_glock *gl, int ret); 242 void gfs2_reclaim_glock(struct gfs2_sbd *sdp); 243 void gfs2_gl_hash_clear(struct gfs2_sbd *sdp); 244 void gfs2_glock_finish_truncate(struct gfs2_inode *ip); 245 void gfs2_glock_thaw(struct gfs2_sbd *sdp); 246 247 int __init gfs2_glock_init(void); 248 void gfs2_glock_exit(void); 249 250 int gfs2_create_debugfs_file(struct gfs2_sbd *sdp); 251 void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp); 252 int gfs2_register_debugfs(void); 253 void gfs2_unregister_debugfs(void); 254 255 extern const struct lm_lockops gfs2_dlm_ops; 256 257 #endif /* __GLOCK_DOT_H__ */ 258