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 struct lm_lockops { 117 const char *lm_proto_name; 118 int (*lm_mount) (struct gfs2_sbd *sdp, const char *fsname); 119 void (*lm_unmount) (struct gfs2_sbd *sdp); 120 void (*lm_withdraw) (struct gfs2_sbd *sdp); 121 void (*lm_put_lock) (struct kmem_cache *cachep, struct gfs2_glock *gl); 122 int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state, 123 unsigned int flags); 124 void (*lm_cancel) (struct gfs2_glock *gl); 125 const match_table_t *lm_tokens; 126 }; 127 128 extern struct workqueue_struct *gfs2_delete_workqueue; 129 static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl) 130 { 131 struct gfs2_holder *gh; 132 struct pid *pid; 133 134 /* Look in glock's list of holders for one with current task as owner */ 135 spin_lock(&gl->gl_spin); 136 pid = task_pid(current); 137 list_for_each_entry(gh, &gl->gl_holders, gh_list) { 138 if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) 139 break; 140 if (gh->gh_owner_pid == pid) 141 goto out; 142 } 143 gh = NULL; 144 out: 145 spin_unlock(&gl->gl_spin); 146 147 return gh; 148 } 149 150 static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl) 151 { 152 return gl->gl_state == LM_ST_EXCLUSIVE; 153 } 154 155 static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl) 156 { 157 return gl->gl_state == LM_ST_DEFERRED; 158 } 159 160 static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl) 161 { 162 return gl->gl_state == LM_ST_SHARED; 163 } 164 165 static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl) 166 { 167 if (gl->gl_ops->go_flags & GLOF_ASPACE) 168 return (struct address_space *)(gl + 1); 169 return NULL; 170 } 171 172 int gfs2_glock_get(struct gfs2_sbd *sdp, 173 u64 number, const struct gfs2_glock_operations *glops, 174 int create, struct gfs2_glock **glp); 175 void gfs2_glock_hold(struct gfs2_glock *gl); 176 void gfs2_glock_put_nolock(struct gfs2_glock *gl); 177 int gfs2_glock_put(struct gfs2_glock *gl); 178 void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, 179 struct gfs2_holder *gh); 180 void gfs2_holder_reinit(unsigned int state, unsigned flags, 181 struct gfs2_holder *gh); 182 void gfs2_holder_uninit(struct gfs2_holder *gh); 183 int gfs2_glock_nq(struct gfs2_holder *gh); 184 int gfs2_glock_poll(struct gfs2_holder *gh); 185 int gfs2_glock_wait(struct gfs2_holder *gh); 186 void gfs2_glock_dq(struct gfs2_holder *gh); 187 void gfs2_glock_dq_wait(struct gfs2_holder *gh); 188 189 void gfs2_glock_dq_uninit(struct gfs2_holder *gh); 190 int gfs2_glock_nq_num(struct gfs2_sbd *sdp, 191 u64 number, const struct gfs2_glock_operations *glops, 192 unsigned int state, int flags, struct gfs2_holder *gh); 193 194 int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs); 195 void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs); 196 void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs); 197 198 __attribute__ ((format(printf, 2, 3))) 199 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...); 200 201 /** 202 * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock 203 * @gl: the glock 204 * @state: the state we're requesting 205 * @flags: the modifier flags 206 * @gh: the holder structure 207 * 208 * Returns: 0, GLR_*, or errno 209 */ 210 211 static inline int gfs2_glock_nq_init(struct gfs2_glock *gl, 212 unsigned int state, int flags, 213 struct gfs2_holder *gh) 214 { 215 int error; 216 217 gfs2_holder_init(gl, state, flags, gh); 218 219 error = gfs2_glock_nq(gh); 220 if (error) 221 gfs2_holder_uninit(gh); 222 223 return error; 224 } 225 226 /* Lock Value Block functions */ 227 228 int gfs2_lvb_hold(struct gfs2_glock *gl); 229 void gfs2_lvb_unhold(struct gfs2_glock *gl); 230 231 void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state); 232 void gfs2_glock_complete(struct gfs2_glock *gl, int ret); 233 void gfs2_reclaim_glock(struct gfs2_sbd *sdp); 234 void gfs2_gl_hash_clear(struct gfs2_sbd *sdp); 235 void gfs2_glock_finish_truncate(struct gfs2_inode *ip); 236 void gfs2_glock_thaw(struct gfs2_sbd *sdp); 237 238 int __init gfs2_glock_init(void); 239 void gfs2_glock_exit(void); 240 241 int gfs2_create_debugfs_file(struct gfs2_sbd *sdp); 242 void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp); 243 int gfs2_register_debugfs(void); 244 void gfs2_unregister_debugfs(void); 245 246 extern const struct lm_lockops gfs2_dlm_ops; 247 248 #endif /* __GLOCK_DOT_H__ */ 249