David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. |
Steven Whitehouse | 3a8a9a1 | 2006-05-18 15:09:15 -0400 | [diff] [blame] | 3 | * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 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 |
Steven Whitehouse | e9fc2aa | 2006-09-01 11:05:15 -0400 | [diff] [blame] | 7 | * of the GNU General Public License version 2. |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 8 | */ |
| 9 | |
| 10 | #include <linux/sched.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/spinlock.h> |
| 13 | #include <linux/completion.h> |
| 14 | #include <linux/buffer_head.h> |
| 15 | #include <linux/delay.h> |
| 16 | #include <linux/sort.h> |
| 17 | #include <linux/jhash.h> |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 18 | #include <linux/kallsyms.h> |
Steven Whitehouse | 5c676f6 | 2006-02-27 17:23:27 -0500 | [diff] [blame] | 19 | #include <linux/gfs2_ondisk.h> |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 20 | #include <linux/list.h> |
Fabio Massimo Di Nitto | 7d30859 | 2006-09-19 07:56:29 +0200 | [diff] [blame] | 21 | #include <linux/lm_interface.h> |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 22 | #include <linux/wait.h> |
akpm@linux-foundation.org | 95d97b7 | 2007-03-05 23:10:39 -0800 | [diff] [blame] | 23 | #include <linux/module.h> |
Steven Whitehouse | 61be084 | 2007-01-29 11:51:45 +0000 | [diff] [blame] | 24 | #include <linux/rwsem.h> |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 25 | #include <asm/uaccess.h> |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 26 | #include <linux/seq_file.h> |
| 27 | #include <linux/debugfs.h> |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 28 | #include <linux/kthread.h> |
| 29 | #include <linux/freezer.h> |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 30 | #include <linux/workqueue.h> |
| 31 | #include <linux/jiffies.h> |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 32 | |
| 33 | #include "gfs2.h" |
Steven Whitehouse | 5c676f6 | 2006-02-27 17:23:27 -0500 | [diff] [blame] | 34 | #include "incore.h" |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 35 | #include "glock.h" |
| 36 | #include "glops.h" |
| 37 | #include "inode.h" |
| 38 | #include "lm.h" |
| 39 | #include "lops.h" |
| 40 | #include "meta_io.h" |
| 41 | #include "quota.h" |
| 42 | #include "super.h" |
Steven Whitehouse | 5c676f6 | 2006-02-27 17:23:27 -0500 | [diff] [blame] | 43 | #include "util.h" |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 44 | |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 45 | struct gfs2_gl_hash_bucket { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 46 | struct hlist_head hb_list; |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 47 | }; |
| 48 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 49 | struct glock_iter { |
| 50 | int hash; /* hash bucket index */ |
| 51 | struct gfs2_sbd *sdp; /* incore superblock */ |
| 52 | struct gfs2_glock *gl; /* current glock struct */ |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 53 | struct seq_file *seq; /* sequence file for debugfs */ |
| 54 | char string[512]; /* scratch space */ |
| 55 | }; |
| 56 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 57 | typedef void (*glock_examiner) (struct gfs2_glock * gl); |
| 58 | |
Adrian Bunk | 08bc2db | 2006-04-28 10:59:12 -0400 | [diff] [blame] | 59 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp); |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 60 | static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 61 | static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh); |
Steven Whitehouse | b5d32be | 2007-01-22 12:15:34 -0500 | [diff] [blame] | 62 | static void gfs2_glock_drop_th(struct gfs2_glock *gl); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 63 | static void run_queue(struct gfs2_glock *gl); |
| 64 | |
Steven Whitehouse | 61be084 | 2007-01-29 11:51:45 +0000 | [diff] [blame] | 65 | static DECLARE_RWSEM(gfs2_umount_flush_sem); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 66 | static struct dentry *gfs2_root; |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 67 | static struct task_struct *scand_process; |
| 68 | static unsigned int scand_secs = 5; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 69 | static struct workqueue_struct *glock_workqueue; |
Adrian Bunk | 08bc2db | 2006-04-28 10:59:12 -0400 | [diff] [blame] | 70 | |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 71 | #define GFS2_GL_HASH_SHIFT 15 |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 72 | #define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT) |
| 73 | #define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1) |
| 74 | |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 75 | static struct gfs2_gl_hash_bucket gl_hash_table[GFS2_GL_HASH_SIZE]; |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 76 | static struct dentry *gfs2_root; |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 77 | |
| 78 | /* |
| 79 | * Despite what you might think, the numbers below are not arbitrary :-) |
| 80 | * They are taken from the ipv4 routing hash code, which is well tested |
| 81 | * and thus should be nearly optimal. Later on we might tweek the numbers |
| 82 | * but for now this should be fine. |
| 83 | * |
| 84 | * The reason for putting the locks in a separate array from the list heads |
| 85 | * is that we can have fewer locks than list heads and save memory. We use |
| 86 | * the same hash function for both, but with a different hash mask. |
| 87 | */ |
| 88 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ |
| 89 | defined(CONFIG_PROVE_LOCKING) |
| 90 | |
| 91 | #ifdef CONFIG_LOCKDEP |
| 92 | # define GL_HASH_LOCK_SZ 256 |
| 93 | #else |
| 94 | # if NR_CPUS >= 32 |
| 95 | # define GL_HASH_LOCK_SZ 4096 |
| 96 | # elif NR_CPUS >= 16 |
| 97 | # define GL_HASH_LOCK_SZ 2048 |
| 98 | # elif NR_CPUS >= 8 |
| 99 | # define GL_HASH_LOCK_SZ 1024 |
| 100 | # elif NR_CPUS >= 4 |
| 101 | # define GL_HASH_LOCK_SZ 512 |
| 102 | # else |
| 103 | # define GL_HASH_LOCK_SZ 256 |
| 104 | # endif |
| 105 | #endif |
| 106 | |
| 107 | /* We never want more locks than chains */ |
| 108 | #if GFS2_GL_HASH_SIZE < GL_HASH_LOCK_SZ |
| 109 | # undef GL_HASH_LOCK_SZ |
| 110 | # define GL_HASH_LOCK_SZ GFS2_GL_HASH_SIZE |
| 111 | #endif |
| 112 | |
| 113 | static rwlock_t gl_hash_locks[GL_HASH_LOCK_SZ]; |
| 114 | |
| 115 | static inline rwlock_t *gl_lock_addr(unsigned int x) |
| 116 | { |
Steven Whitehouse | 9461061 | 2006-09-09 18:59:27 -0400 | [diff] [blame] | 117 | return &gl_hash_locks[x & (GL_HASH_LOCK_SZ-1)]; |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 118 | } |
| 119 | #else /* not SMP, so no spinlocks required */ |
Randy Dunlap | 0ac2306 | 2006-11-28 22:29:19 -0800 | [diff] [blame] | 120 | static inline rwlock_t *gl_lock_addr(unsigned int x) |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 121 | { |
| 122 | return NULL; |
| 123 | } |
| 124 | #endif |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 125 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 126 | /** |
| 127 | * relaxed_state_ok - is a requested lock compatible with the current lock mode? |
| 128 | * @actual: the current state of the lock |
| 129 | * @requested: the lock state that was requested by the caller |
| 130 | * @flags: the modifier flags passed in by the caller |
| 131 | * |
| 132 | * Returns: 1 if the locks are compatible, 0 otherwise |
| 133 | */ |
| 134 | |
| 135 | static inline int relaxed_state_ok(unsigned int actual, unsigned requested, |
| 136 | int flags) |
| 137 | { |
| 138 | if (actual == requested) |
| 139 | return 1; |
| 140 | |
| 141 | if (flags & GL_EXACT) |
| 142 | return 0; |
| 143 | |
| 144 | if (actual == LM_ST_EXCLUSIVE && requested == LM_ST_SHARED) |
| 145 | return 1; |
| 146 | |
| 147 | if (actual != LM_ST_UNLOCKED && (flags & LM_FLAG_ANY)) |
| 148 | return 1; |
| 149 | |
| 150 | return 0; |
| 151 | } |
| 152 | |
| 153 | /** |
| 154 | * gl_hash() - Turn glock number into hash bucket number |
| 155 | * @lock: The glock number |
| 156 | * |
| 157 | * Returns: The number of the corresponding hash bucket |
| 158 | */ |
| 159 | |
Steven Whitehouse | b854785 | 2006-09-07 13:12:27 -0400 | [diff] [blame] | 160 | static unsigned int gl_hash(const struct gfs2_sbd *sdp, |
| 161 | const struct lm_lockname *name) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 162 | { |
| 163 | unsigned int h; |
| 164 | |
Steven Whitehouse | cd91549 | 2006-09-04 12:49:07 -0400 | [diff] [blame] | 165 | h = jhash(&name->ln_number, sizeof(u64), 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 166 | h = jhash(&name->ln_type, sizeof(unsigned int), h); |
Steven Whitehouse | b854785 | 2006-09-07 13:12:27 -0400 | [diff] [blame] | 167 | h = jhash(&sdp, sizeof(struct gfs2_sbd *), h); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 168 | h &= GFS2_GL_HASH_MASK; |
| 169 | |
| 170 | return h; |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * glock_free() - Perform a few checks and then release struct gfs2_glock |
| 175 | * @gl: The glock to release |
| 176 | * |
| 177 | * Also calls lock module to release its internal structure for this glock. |
| 178 | * |
| 179 | */ |
| 180 | |
| 181 | static void glock_free(struct gfs2_glock *gl) |
| 182 | { |
| 183 | struct gfs2_sbd *sdp = gl->gl_sbd; |
| 184 | struct inode *aspace = gl->gl_aspace; |
| 185 | |
| 186 | gfs2_lm_put_lock(sdp, gl->gl_lock); |
| 187 | |
| 188 | if (aspace) |
| 189 | gfs2_aspace_put(aspace); |
| 190 | |
| 191 | kmem_cache_free(gfs2_glock_cachep, gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 192 | } |
| 193 | |
| 194 | /** |
| 195 | * gfs2_glock_hold() - increment reference count on glock |
| 196 | * @gl: The glock to hold |
| 197 | * |
| 198 | */ |
| 199 | |
| 200 | void gfs2_glock_hold(struct gfs2_glock *gl) |
| 201 | { |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 202 | atomic_inc(&gl->gl_ref); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 203 | } |
| 204 | |
| 205 | /** |
| 206 | * gfs2_glock_put() - Decrement reference count on glock |
| 207 | * @gl: The glock to put |
| 208 | * |
| 209 | */ |
| 210 | |
| 211 | int gfs2_glock_put(struct gfs2_glock *gl) |
| 212 | { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 213 | int rv = 0; |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 214 | struct gfs2_sbd *sdp = gl->gl_sbd; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 215 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 216 | write_lock(gl_lock_addr(gl->gl_hash)); |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 217 | if (atomic_dec_and_test(&gl->gl_ref)) { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 218 | hlist_del(&gl->gl_list); |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 219 | write_unlock(gl_lock_addr(gl->gl_hash)); |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 220 | BUG_ON(spin_is_locked(&gl->gl_spin)); |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 221 | gfs2_assert(sdp, gl->gl_state == LM_ST_UNLOCKED); |
| 222 | gfs2_assert(sdp, list_empty(&gl->gl_reclaim)); |
| 223 | gfs2_assert(sdp, list_empty(&gl->gl_holders)); |
| 224 | gfs2_assert(sdp, list_empty(&gl->gl_waiters1)); |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 225 | gfs2_assert(sdp, list_empty(&gl->gl_waiters3)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 226 | glock_free(gl); |
| 227 | rv = 1; |
| 228 | goto out; |
| 229 | } |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 230 | write_unlock(gl_lock_addr(gl->gl_hash)); |
Steven Whitehouse | a2242db | 2006-08-24 17:03:05 -0400 | [diff] [blame] | 231 | out: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 232 | return rv; |
| 233 | } |
| 234 | |
| 235 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 236 | * search_bucket() - Find struct gfs2_glock by lock number |
| 237 | * @bucket: the bucket to search |
| 238 | * @name: The lock name |
| 239 | * |
| 240 | * Returns: NULL, or the struct gfs2_glock with the requested number |
| 241 | */ |
| 242 | |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 243 | static struct gfs2_glock *search_bucket(unsigned int hash, |
Steven Whitehouse | 899be4d | 2006-08-30 12:50:28 -0400 | [diff] [blame] | 244 | const struct gfs2_sbd *sdp, |
Steven Whitehouse | d6a5372 | 2006-08-30 11:16:23 -0400 | [diff] [blame] | 245 | const struct lm_lockname *name) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 246 | { |
| 247 | struct gfs2_glock *gl; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 248 | struct hlist_node *h; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 249 | |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 250 | hlist_for_each_entry(gl, h, &gl_hash_table[hash].hb_list, gl_list) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 251 | if (!lm_name_equal(&gl->gl_name, name)) |
| 252 | continue; |
Steven Whitehouse | 899be4d | 2006-08-30 12:50:28 -0400 | [diff] [blame] | 253 | if (gl->gl_sbd != sdp) |
| 254 | continue; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 255 | |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 256 | atomic_inc(&gl->gl_ref); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 257 | |
| 258 | return gl; |
| 259 | } |
| 260 | |
| 261 | return NULL; |
| 262 | } |
| 263 | |
| 264 | /** |
| 265 | * gfs2_glock_find() - Find glock by lock number |
| 266 | * @sdp: The GFS2 superblock |
| 267 | * @name: The lock name |
| 268 | * |
| 269 | * Returns: NULL, or the struct gfs2_glock with the requested number |
| 270 | */ |
| 271 | |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 272 | static struct gfs2_glock *gfs2_glock_find(const struct gfs2_sbd *sdp, |
Steven Whitehouse | d6a5372 | 2006-08-30 11:16:23 -0400 | [diff] [blame] | 273 | const struct lm_lockname *name) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 274 | { |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 275 | unsigned int hash = gl_hash(sdp, name); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 276 | struct gfs2_glock *gl; |
| 277 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 278 | read_lock(gl_lock_addr(hash)); |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 279 | gl = search_bucket(hash, sdp, name); |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 280 | read_unlock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 281 | |
| 282 | return gl; |
| 283 | } |
| 284 | |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 285 | static void glock_work_func(struct work_struct *work) |
| 286 | { |
| 287 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work); |
| 288 | |
| 289 | spin_lock(&gl->gl_spin); |
| 290 | if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags)) |
| 291 | set_bit(GLF_DEMOTE, &gl->gl_flags); |
| 292 | run_queue(gl); |
| 293 | spin_unlock(&gl->gl_spin); |
| 294 | gfs2_glock_put(gl); |
| 295 | } |
| 296 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 297 | /** |
| 298 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist |
| 299 | * @sdp: The GFS2 superblock |
| 300 | * @number: the lock number |
| 301 | * @glops: The glock_operations to use |
| 302 | * @create: If 0, don't create the glock if it doesn't exist |
| 303 | * @glp: the glock is returned here |
| 304 | * |
| 305 | * This does not lock a glock, just finds/creates structures for one. |
| 306 | * |
| 307 | * Returns: errno |
| 308 | */ |
| 309 | |
Steven Whitehouse | cd91549 | 2006-09-04 12:49:07 -0400 | [diff] [blame] | 310 | int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 311 | const struct gfs2_glock_operations *glops, int create, |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 312 | struct gfs2_glock **glp) |
| 313 | { |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 314 | struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type }; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 315 | struct gfs2_glock *gl, *tmp; |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 316 | unsigned int hash = gl_hash(sdp, &name); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 317 | int error; |
| 318 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 319 | read_lock(gl_lock_addr(hash)); |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 320 | gl = search_bucket(hash, sdp, &name); |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 321 | read_unlock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 322 | |
| 323 | if (gl || !create) { |
| 324 | *glp = gl; |
| 325 | return 0; |
| 326 | } |
| 327 | |
| 328 | gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL); |
| 329 | if (!gl) |
| 330 | return -ENOMEM; |
| 331 | |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 332 | gl->gl_flags = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 333 | gl->gl_name = name; |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 334 | atomic_set(&gl->gl_ref, 1); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 335 | gl->gl_state = LM_ST_UNLOCKED; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 336 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 337 | gl->gl_hash = hash; |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 338 | gl->gl_owner_pid = 0; |
Steven Whitehouse | 320dd10 | 2006-05-18 16:25:27 -0400 | [diff] [blame] | 339 | gl->gl_ip = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 340 | gl->gl_ops = glops; |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 341 | gl->gl_req_gh = NULL; |
| 342 | gl->gl_req_bh = NULL; |
| 343 | gl->gl_vn = 0; |
| 344 | gl->gl_stamp = jiffies; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 345 | gl->gl_tchange = jiffies; |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 346 | gl->gl_object = NULL; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 347 | gl->gl_sbd = sdp; |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 348 | gl->gl_aspace = NULL; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 349 | lops_init_le(&gl->gl_le, &gfs2_glock_lops); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 350 | INIT_DELAYED_WORK(&gl->gl_work, glock_work_func); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 351 | |
| 352 | /* If this glock protects actual on-disk data or metadata blocks, |
| 353 | create a VFS inode to manage the pages/buffers holding them. */ |
Steven Whitehouse | 5029996 | 2006-09-04 09:49:55 -0400 | [diff] [blame] | 354 | if (glops == &gfs2_inode_glops || glops == &gfs2_rgrp_glops) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 355 | gl->gl_aspace = gfs2_aspace_get(sdp); |
| 356 | if (!gl->gl_aspace) { |
| 357 | error = -ENOMEM; |
| 358 | goto fail; |
| 359 | } |
| 360 | } |
| 361 | |
| 362 | error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); |
| 363 | if (error) |
| 364 | goto fail_aspace; |
| 365 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 366 | write_lock(gl_lock_addr(hash)); |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 367 | tmp = search_bucket(hash, sdp, &name); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 368 | if (tmp) { |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 369 | write_unlock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 370 | glock_free(gl); |
| 371 | gl = tmp; |
| 372 | } else { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 373 | hlist_add_head(&gl->gl_list, &gl_hash_table[hash].hb_list); |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 374 | write_unlock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 375 | } |
| 376 | |
| 377 | *glp = gl; |
| 378 | |
| 379 | return 0; |
| 380 | |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 381 | fail_aspace: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 382 | if (gl->gl_aspace) |
| 383 | gfs2_aspace_put(gl->gl_aspace); |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 384 | fail: |
Steven Whitehouse | 907b9bc | 2006-09-25 09:26:04 -0400 | [diff] [blame] | 385 | kmem_cache_free(gfs2_glock_cachep, gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 386 | return error; |
| 387 | } |
| 388 | |
| 389 | /** |
| 390 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way |
| 391 | * @gl: the glock |
| 392 | * @state: the state we're requesting |
| 393 | * @flags: the modifier flags |
| 394 | * @gh: the holder structure |
| 395 | * |
| 396 | */ |
| 397 | |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 398 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 399 | struct gfs2_holder *gh) |
| 400 | { |
| 401 | INIT_LIST_HEAD(&gh->gh_list); |
| 402 | gh->gh_gl = gl; |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 403 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 404 | gh->gh_owner_pid = current->pid; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 405 | gh->gh_state = state; |
| 406 | gh->gh_flags = flags; |
| 407 | gh->gh_error = 0; |
| 408 | gh->gh_iflags = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 409 | gfs2_glock_hold(gl); |
| 410 | } |
| 411 | |
| 412 | /** |
| 413 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it |
| 414 | * @state: the state we're requesting |
| 415 | * @flags: the modifier flags |
| 416 | * @gh: the holder structure |
| 417 | * |
| 418 | * Don't mess with the glock. |
| 419 | * |
| 420 | */ |
| 421 | |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 422 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 423 | { |
| 424 | gh->gh_state = state; |
Steven Whitehouse | 579b78a | 2006-04-26 14:58:26 -0400 | [diff] [blame] | 425 | gh->gh_flags = flags; |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 426 | gh->gh_iflags = 0; |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 427 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 428 | } |
| 429 | |
| 430 | /** |
| 431 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) |
| 432 | * @gh: the holder structure |
| 433 | * |
| 434 | */ |
| 435 | |
| 436 | void gfs2_holder_uninit(struct gfs2_holder *gh) |
| 437 | { |
| 438 | gfs2_glock_put(gh->gh_gl); |
| 439 | gh->gh_gl = NULL; |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 440 | gh->gh_ip = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 441 | } |
| 442 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 443 | static void gfs2_holder_wake(struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 444 | { |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 445 | clear_bit(HIF_WAIT, &gh->gh_iflags); |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 446 | smp_mb__after_clear_bit(); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 447 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); |
| 448 | } |
| 449 | |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 450 | static int just_schedule(void *word) |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 451 | { |
| 452 | schedule(); |
| 453 | return 0; |
| 454 | } |
| 455 | |
| 456 | static void wait_on_holder(struct gfs2_holder *gh) |
| 457 | { |
| 458 | might_sleep(); |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 459 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, just_schedule, TASK_UNINTERRUPTIBLE); |
| 460 | } |
| 461 | |
| 462 | static void gfs2_demote_wake(struct gfs2_glock *gl) |
| 463 | { |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 464 | BUG_ON(!spin_is_locked(&gl->gl_spin)); |
| 465 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 466 | clear_bit(GLF_DEMOTE, &gl->gl_flags); |
| 467 | smp_mb__after_clear_bit(); |
| 468 | wake_up_bit(&gl->gl_flags, GLF_DEMOTE); |
| 469 | } |
| 470 | |
| 471 | static void wait_on_demote(struct gfs2_glock *gl) |
| 472 | { |
| 473 | might_sleep(); |
| 474 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, just_schedule, TASK_UNINTERRUPTIBLE); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 475 | } |
| 476 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 477 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 478 | * rq_mutex - process a mutex request in the queue |
| 479 | * @gh: the glock holder |
| 480 | * |
| 481 | * Returns: 1 if the queue is blocked |
| 482 | */ |
| 483 | |
| 484 | static int rq_mutex(struct gfs2_holder *gh) |
| 485 | { |
| 486 | struct gfs2_glock *gl = gh->gh_gl; |
| 487 | |
| 488 | list_del_init(&gh->gh_list); |
| 489 | /* gh->gh_error never examined. */ |
| 490 | set_bit(GLF_LOCK, &gl->gl_flags); |
Steven Whitehouse | d043e19 | 2007-01-23 16:56:36 -0500 | [diff] [blame] | 491 | clear_bit(HIF_WAIT, &gh->gh_iflags); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 492 | smp_mb(); |
| 493 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 494 | |
| 495 | return 1; |
| 496 | } |
| 497 | |
| 498 | /** |
| 499 | * rq_promote - process a promote request in the queue |
| 500 | * @gh: the glock holder |
| 501 | * |
| 502 | * Acquire a new inter-node lock, or change a lock state to more restrictive. |
| 503 | * |
| 504 | * Returns: 1 if the queue is blocked |
| 505 | */ |
| 506 | |
| 507 | static int rq_promote(struct gfs2_holder *gh) |
| 508 | { |
| 509 | struct gfs2_glock *gl = gh->gh_gl; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 510 | |
| 511 | if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { |
| 512 | if (list_empty(&gl->gl_holders)) { |
| 513 | gl->gl_req_gh = gh; |
| 514 | set_bit(GLF_LOCK, &gl->gl_flags); |
| 515 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 516 | gfs2_glock_xmote_th(gh->gh_gl, gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 517 | spin_lock(&gl->gl_spin); |
| 518 | } |
| 519 | return 1; |
| 520 | } |
| 521 | |
| 522 | if (list_empty(&gl->gl_holders)) { |
| 523 | set_bit(HIF_FIRST, &gh->gh_iflags); |
| 524 | set_bit(GLF_LOCK, &gl->gl_flags); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 525 | } else { |
| 526 | struct gfs2_holder *next_gh; |
Steven Whitehouse | 1c0f487 | 2007-01-22 12:10:39 -0500 | [diff] [blame] | 527 | if (gh->gh_state == LM_ST_EXCLUSIVE) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 528 | return 1; |
| 529 | next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder, |
| 530 | gh_list); |
Steven Whitehouse | 1c0f487 | 2007-01-22 12:10:39 -0500 | [diff] [blame] | 531 | if (next_gh->gh_state == LM_ST_EXCLUSIVE) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 532 | return 1; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 533 | } |
| 534 | |
| 535 | list_move_tail(&gh->gh_list, &gl->gl_holders); |
| 536 | gh->gh_error = 0; |
| 537 | set_bit(HIF_HOLDER, &gh->gh_iflags); |
| 538 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 539 | gfs2_holder_wake(gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 540 | |
| 541 | return 0; |
| 542 | } |
| 543 | |
| 544 | /** |
| 545 | * rq_demote - process a demote request in the queue |
| 546 | * @gh: the glock holder |
| 547 | * |
| 548 | * Returns: 1 if the queue is blocked |
| 549 | */ |
| 550 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 551 | static int rq_demote(struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 552 | { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 553 | if (!list_empty(&gl->gl_holders)) |
| 554 | return 1; |
| 555 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 556 | if (gl->gl_state == gl->gl_demote_state || |
| 557 | gl->gl_state == LM_ST_UNLOCKED) { |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 558 | gfs2_demote_wake(gl); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 559 | return 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 560 | } |
Wendy Cheng | cc7e79b | 2007-10-05 00:27:58 -0400 | [diff] [blame] | 561 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 562 | set_bit(GLF_LOCK, &gl->gl_flags); |
Wendy Cheng | cc7e79b | 2007-10-05 00:27:58 -0400 | [diff] [blame] | 563 | set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); |
| 564 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 565 | if (gl->gl_demote_state == LM_ST_UNLOCKED || |
Steven Whitehouse | 87124e5 | 2007-07-23 09:54:36 +0100 | [diff] [blame] | 566 | gl->gl_state != LM_ST_EXCLUSIVE) { |
| 567 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 568 | gfs2_glock_drop_th(gl); |
Steven Whitehouse | 87124e5 | 2007-07-23 09:54:36 +0100 | [diff] [blame] | 569 | } else { |
| 570 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 571 | gfs2_glock_xmote_th(gl, NULL); |
Steven Whitehouse | 87124e5 | 2007-07-23 09:54:36 +0100 | [diff] [blame] | 572 | } |
Wendy Cheng | cc7e79b | 2007-10-05 00:27:58 -0400 | [diff] [blame] | 573 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 574 | spin_lock(&gl->gl_spin); |
Wendy Cheng | cc7e79b | 2007-10-05 00:27:58 -0400 | [diff] [blame] | 575 | clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 576 | |
| 577 | return 0; |
| 578 | } |
| 579 | |
| 580 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 581 | * run_queue - process holder structures on a glock |
| 582 | * @gl: the glock |
| 583 | * |
| 584 | */ |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 585 | static void run_queue(struct gfs2_glock *gl) |
| 586 | { |
| 587 | struct gfs2_holder *gh; |
| 588 | int blocked = 1; |
| 589 | |
| 590 | for (;;) { |
| 591 | if (test_bit(GLF_LOCK, &gl->gl_flags)) |
| 592 | break; |
| 593 | |
| 594 | if (!list_empty(&gl->gl_waiters1)) { |
| 595 | gh = list_entry(gl->gl_waiters1.next, |
| 596 | struct gfs2_holder, gh_list); |
Steven Whitehouse | e589665 | 2007-11-02 09:14:31 +0000 | [diff] [blame] | 597 | blocked = rq_mutex(gh); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 598 | } else if (test_bit(GLF_DEMOTE, &gl->gl_flags)) { |
| 599 | blocked = rq_demote(gl); |
Wendy Cheng | cc7e79b | 2007-10-05 00:27:58 -0400 | [diff] [blame] | 600 | if (gl->gl_waiters2 && !blocked) { |
| 601 | set_bit(GLF_DEMOTE, &gl->gl_flags); |
| 602 | gl->gl_demote_state = LM_ST_UNLOCKED; |
| 603 | } |
| 604 | gl->gl_waiters2 = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 605 | } else if (!list_empty(&gl->gl_waiters3)) { |
| 606 | gh = list_entry(gl->gl_waiters3.next, |
| 607 | struct gfs2_holder, gh_list); |
Steven Whitehouse | e589665 | 2007-11-02 09:14:31 +0000 | [diff] [blame] | 608 | blocked = rq_promote(gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 609 | } else |
| 610 | break; |
| 611 | |
| 612 | if (blocked) |
| 613 | break; |
| 614 | } |
| 615 | } |
| 616 | |
| 617 | /** |
| 618 | * gfs2_glmutex_lock - acquire a local lock on a glock |
| 619 | * @gl: the glock |
| 620 | * |
| 621 | * Gives caller exclusive access to manipulate a glock structure. |
| 622 | */ |
| 623 | |
Steven Whitehouse | feaa7bb | 2006-06-14 15:32:57 -0400 | [diff] [blame] | 624 | static void gfs2_glmutex_lock(struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 625 | { |
| 626 | struct gfs2_holder gh; |
| 627 | |
| 628 | gfs2_holder_init(gl, 0, 0, &gh); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 629 | if (test_and_set_bit(HIF_WAIT, &gh.gh_iflags)) |
| 630 | BUG(); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 631 | |
| 632 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 633 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 634 | list_add_tail(&gh.gh_list, &gl->gl_waiters1); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 635 | } else { |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 636 | gl->gl_owner_pid = current->pid; |
Steven Whitehouse | 320dd10 | 2006-05-18 16:25:27 -0400 | [diff] [blame] | 637 | gl->gl_ip = (unsigned long)__builtin_return_address(0); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 638 | clear_bit(HIF_WAIT, &gh.gh_iflags); |
| 639 | smp_mb(); |
| 640 | wake_up_bit(&gh.gh_iflags, HIF_WAIT); |
Steven Whitehouse | 320dd10 | 2006-05-18 16:25:27 -0400 | [diff] [blame] | 641 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 642 | spin_unlock(&gl->gl_spin); |
| 643 | |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 644 | wait_on_holder(&gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 645 | gfs2_holder_uninit(&gh); |
| 646 | } |
| 647 | |
| 648 | /** |
| 649 | * gfs2_glmutex_trylock - try to acquire a local lock on a glock |
| 650 | * @gl: the glock |
| 651 | * |
| 652 | * Returns: 1 if the glock is acquired |
| 653 | */ |
| 654 | |
Adrian Bunk | 08bc2db | 2006-04-28 10:59:12 -0400 | [diff] [blame] | 655 | static int gfs2_glmutex_trylock(struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 656 | { |
| 657 | int acquired = 1; |
| 658 | |
| 659 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 660 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 661 | acquired = 0; |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 662 | } else { |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 663 | gl->gl_owner_pid = current->pid; |
Steven Whitehouse | 320dd10 | 2006-05-18 16:25:27 -0400 | [diff] [blame] | 664 | gl->gl_ip = (unsigned long)__builtin_return_address(0); |
| 665 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 666 | spin_unlock(&gl->gl_spin); |
| 667 | |
| 668 | return acquired; |
| 669 | } |
| 670 | |
| 671 | /** |
| 672 | * gfs2_glmutex_unlock - release a local lock on a glock |
| 673 | * @gl: the glock |
| 674 | * |
| 675 | */ |
| 676 | |
Steven Whitehouse | feaa7bb | 2006-06-14 15:32:57 -0400 | [diff] [blame] | 677 | static void gfs2_glmutex_unlock(struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 678 | { |
| 679 | spin_lock(&gl->gl_spin); |
| 680 | clear_bit(GLF_LOCK, &gl->gl_flags); |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 681 | gl->gl_owner_pid = 0; |
Steven Whitehouse | 320dd10 | 2006-05-18 16:25:27 -0400 | [diff] [blame] | 682 | gl->gl_ip = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 683 | run_queue(gl); |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 684 | BUG_ON(!spin_is_locked(&gl->gl_spin)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 685 | spin_unlock(&gl->gl_spin); |
| 686 | } |
| 687 | |
| 688 | /** |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 689 | * handle_callback - process a demote request |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 690 | * @gl: the glock |
| 691 | * @state: the state the caller wants us to change to |
| 692 | * |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 693 | * There are only two requests that we are going to see in actual |
| 694 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 695 | */ |
| 696 | |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 697 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
| 698 | int remote, unsigned long delay) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 699 | { |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 700 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
| 701 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 702 | spin_lock(&gl->gl_spin); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 703 | set_bit(bit, &gl->gl_flags); |
| 704 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 705 | gl->gl_demote_state = state; |
| 706 | gl->gl_demote_time = jiffies; |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 707 | if (remote && gl->gl_ops->go_type == LM_TYPE_IOPEN && |
| 708 | gl->gl_object) { |
Wendy Cheng | 49e61f2 | 2007-09-13 17:52:42 -0400 | [diff] [blame] | 709 | gfs2_glock_schedule_for_reclaim(gl); |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 710 | spin_unlock(&gl->gl_spin); |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 711 | return; |
| 712 | } |
Josef Whiter | 26caee5 | 2007-07-23 10:02:40 +0100 | [diff] [blame] | 713 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
| 714 | gl->gl_demote_state != state) { |
Wendy Cheng | cc7e79b | 2007-10-05 00:27:58 -0400 | [diff] [blame] | 715 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) |
| 716 | gl->gl_waiters2 = 1; |
| 717 | else |
| 718 | gl->gl_demote_state = LM_ST_UNLOCKED; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 719 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 720 | spin_unlock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 721 | } |
| 722 | |
| 723 | /** |
| 724 | * state_change - record that the glock is now in a different state |
| 725 | * @gl: the glock |
| 726 | * @new_state the new state |
| 727 | * |
| 728 | */ |
| 729 | |
| 730 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) |
| 731 | { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 732 | int held1, held2; |
| 733 | |
| 734 | held1 = (gl->gl_state != LM_ST_UNLOCKED); |
| 735 | held2 = (new_state != LM_ST_UNLOCKED); |
| 736 | |
| 737 | if (held1 != held2) { |
David Teigland | 6a6b3d0 | 2006-02-23 10:11:47 +0000 | [diff] [blame] | 738 | if (held2) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 739 | gfs2_glock_hold(gl); |
David Teigland | 6a6b3d0 | 2006-02-23 10:11:47 +0000 | [diff] [blame] | 740 | else |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 741 | gfs2_glock_put(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 742 | } |
| 743 | |
| 744 | gl->gl_state = new_state; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 745 | gl->gl_tchange = jiffies; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 746 | } |
| 747 | |
| 748 | /** |
| 749 | * xmote_bh - Called after the lock module is done acquiring a lock |
| 750 | * @gl: The glock in question |
| 751 | * @ret: the int returned from the lock module |
| 752 | * |
| 753 | */ |
| 754 | |
| 755 | static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) |
| 756 | { |
| 757 | struct gfs2_sbd *sdp = gl->gl_sbd; |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 758 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 759 | struct gfs2_holder *gh = gl->gl_req_gh; |
| 760 | int prev_state = gl->gl_state; |
| 761 | int op_done = 1; |
| 762 | |
| 763 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
Steven Whitehouse | 1213293 | 2007-01-22 13:09:04 -0500 | [diff] [blame] | 764 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 765 | gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC)); |
| 766 | |
| 767 | state_change(gl, ret & LM_OUT_ST_MASK); |
| 768 | |
| 769 | if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) { |
| 770 | if (glops->go_inval) |
Steven Whitehouse | 1a14d3a | 2006-11-20 10:37:45 -0500 | [diff] [blame] | 771 | glops->go_inval(gl, DIO_METADATA); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 772 | } else if (gl->gl_state == LM_ST_DEFERRED) { |
| 773 | /* We might not want to do this here. |
| 774 | Look at moving to the inode glops. */ |
| 775 | if (glops->go_inval) |
Steven Whitehouse | 1a14d3a | 2006-11-20 10:37:45 -0500 | [diff] [blame] | 776 | glops->go_inval(gl, 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 777 | } |
| 778 | |
| 779 | /* Deal with each possible exit condition */ |
| 780 | |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 781 | if (!gh) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 782 | gl->gl_stamp = jiffies; |
Steven Whitehouse | 87124e5 | 2007-07-23 09:54:36 +0100 | [diff] [blame] | 783 | if (ret & LM_OUT_CANCELED) { |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 784 | op_done = 0; |
Steven Whitehouse | 87124e5 | 2007-07-23 09:54:36 +0100 | [diff] [blame] | 785 | } else { |
| 786 | spin_lock(&gl->gl_spin); |
| 787 | if (gl->gl_state != gl->gl_demote_state) { |
| 788 | gl->gl_req_bh = NULL; |
| 789 | spin_unlock(&gl->gl_spin); |
| 790 | gfs2_glock_drop_th(gl); |
| 791 | gfs2_glock_put(gl); |
| 792 | return; |
| 793 | } |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 794 | gfs2_demote_wake(gl); |
Steven Whitehouse | 87124e5 | 2007-07-23 09:54:36 +0100 | [diff] [blame] | 795 | spin_unlock(&gl->gl_spin); |
| 796 | } |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 797 | } else { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 798 | spin_lock(&gl->gl_spin); |
| 799 | list_del_init(&gh->gh_list); |
| 800 | gh->gh_error = -EIO; |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 801 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
| 802 | goto out; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 803 | gh->gh_error = GLR_CANCELED; |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 804 | if (ret & LM_OUT_CANCELED) |
| 805 | goto out; |
| 806 | if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { |
| 807 | list_add_tail(&gh->gh_list, &gl->gl_holders); |
| 808 | gh->gh_error = 0; |
| 809 | set_bit(HIF_HOLDER, &gh->gh_iflags); |
| 810 | set_bit(HIF_FIRST, &gh->gh_iflags); |
| 811 | op_done = 0; |
| 812 | goto out; |
| 813 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 814 | gh->gh_error = GLR_TRYFAILED; |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 815 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) |
| 816 | goto out; |
| 817 | gh->gh_error = -EINVAL; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 818 | if (gfs2_assert_withdraw(sdp, 0) == -1) |
| 819 | fs_err(sdp, "ret = 0x%.8X\n", ret); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 820 | out: |
| 821 | spin_unlock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 822 | } |
| 823 | |
| 824 | if (glops->go_xmote_bh) |
| 825 | glops->go_xmote_bh(gl); |
| 826 | |
| 827 | if (op_done) { |
| 828 | spin_lock(&gl->gl_spin); |
| 829 | gl->gl_req_gh = NULL; |
| 830 | gl->gl_req_bh = NULL; |
| 831 | clear_bit(GLF_LOCK, &gl->gl_flags); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 832 | spin_unlock(&gl->gl_spin); |
| 833 | } |
| 834 | |
| 835 | gfs2_glock_put(gl); |
| 836 | |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 837 | if (gh) |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 838 | gfs2_holder_wake(gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 839 | } |
| 840 | |
| 841 | /** |
| 842 | * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock |
| 843 | * @gl: The glock in question |
| 844 | * @state: the requested state |
| 845 | * @flags: modifier flags to the lock call |
| 846 | * |
| 847 | */ |
| 848 | |
Steven Whitehouse | 87124e5 | 2007-07-23 09:54:36 +0100 | [diff] [blame] | 849 | static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 850 | { |
| 851 | struct gfs2_sbd *sdp = gl->gl_sbd; |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 852 | int flags = gh ? gh->gh_flags : 0; |
| 853 | unsigned state = gh ? gh->gh_state : gl->gl_demote_state; |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 854 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 855 | int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB | |
| 856 | LM_FLAG_NOEXP | LM_FLAG_ANY | |
| 857 | LM_FLAG_PRIORITY); |
| 858 | unsigned int lck_ret; |
| 859 | |
Steven Whitehouse | b5d32be | 2007-01-22 12:15:34 -0500 | [diff] [blame] | 860 | if (glops->go_xmote_th) |
| 861 | glops->go_xmote_th(gl); |
| 862 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 863 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
Steven Whitehouse | 1213293 | 2007-01-22 13:09:04 -0500 | [diff] [blame] | 864 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 865 | gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED); |
| 866 | gfs2_assert_warn(sdp, state != gl->gl_state); |
| 867 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 868 | gfs2_glock_hold(gl); |
| 869 | gl->gl_req_bh = xmote_bh; |
| 870 | |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 871 | lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 872 | |
| 873 | if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR))) |
| 874 | return; |
| 875 | |
| 876 | if (lck_ret & LM_OUT_ASYNC) |
| 877 | gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC); |
| 878 | else |
| 879 | xmote_bh(gl, lck_ret); |
| 880 | } |
| 881 | |
| 882 | /** |
| 883 | * drop_bh - Called after a lock module unlock completes |
| 884 | * @gl: the glock |
| 885 | * @ret: the return status |
| 886 | * |
| 887 | * Doesn't wake up the process waiting on the struct gfs2_holder (if any) |
| 888 | * Doesn't drop the reference on the glock the top half took out |
| 889 | * |
| 890 | */ |
| 891 | |
| 892 | static void drop_bh(struct gfs2_glock *gl, unsigned int ret) |
| 893 | { |
| 894 | struct gfs2_sbd *sdp = gl->gl_sbd; |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 895 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 896 | struct gfs2_holder *gh = gl->gl_req_gh; |
| 897 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 898 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
Steven Whitehouse | 1213293 | 2007-01-22 13:09:04 -0500 | [diff] [blame] | 899 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 900 | gfs2_assert_warn(sdp, !ret); |
| 901 | |
| 902 | state_change(gl, LM_ST_UNLOCKED); |
| 903 | |
| 904 | if (glops->go_inval) |
Steven Whitehouse | 1a14d3a | 2006-11-20 10:37:45 -0500 | [diff] [blame] | 905 | glops->go_inval(gl, DIO_METADATA); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 906 | |
| 907 | if (gh) { |
| 908 | spin_lock(&gl->gl_spin); |
| 909 | list_del_init(&gh->gh_list); |
| 910 | gh->gh_error = 0; |
| 911 | spin_unlock(&gl->gl_spin); |
| 912 | } |
| 913 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 914 | spin_lock(&gl->gl_spin); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 915 | gfs2_demote_wake(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 916 | gl->gl_req_gh = NULL; |
| 917 | gl->gl_req_bh = NULL; |
| 918 | clear_bit(GLF_LOCK, &gl->gl_flags); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 919 | spin_unlock(&gl->gl_spin); |
| 920 | |
| 921 | gfs2_glock_put(gl); |
| 922 | |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 923 | if (gh) |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 924 | gfs2_holder_wake(gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 925 | } |
| 926 | |
| 927 | /** |
| 928 | * gfs2_glock_drop_th - call into the lock module to unlock a lock |
| 929 | * @gl: the glock |
| 930 | * |
| 931 | */ |
| 932 | |
Steven Whitehouse | b5d32be | 2007-01-22 12:15:34 -0500 | [diff] [blame] | 933 | static void gfs2_glock_drop_th(struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 934 | { |
| 935 | struct gfs2_sbd *sdp = gl->gl_sbd; |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 936 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 937 | unsigned int ret; |
| 938 | |
Steven Whitehouse | 3042a2c | 2007-11-02 08:39:34 +0000 | [diff] [blame] | 939 | if (glops->go_xmote_th) |
| 940 | glops->go_xmote_th(gl); |
Steven Whitehouse | b5d32be | 2007-01-22 12:15:34 -0500 | [diff] [blame] | 941 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 942 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
Steven Whitehouse | 1213293 | 2007-01-22 13:09:04 -0500 | [diff] [blame] | 943 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 944 | gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED); |
| 945 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 946 | gfs2_glock_hold(gl); |
| 947 | gl->gl_req_bh = drop_bh; |
| 948 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 949 | ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state); |
| 950 | |
| 951 | if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR))) |
| 952 | return; |
| 953 | |
| 954 | if (!ret) |
| 955 | drop_bh(gl, ret); |
| 956 | else |
| 957 | gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC); |
| 958 | } |
| 959 | |
| 960 | /** |
| 961 | * do_cancels - cancel requests for locks stuck waiting on an expire flag |
| 962 | * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock |
| 963 | * |
| 964 | * Don't cancel GL_NOCANCEL requests. |
| 965 | */ |
| 966 | |
| 967 | static void do_cancels(struct gfs2_holder *gh) |
| 968 | { |
| 969 | struct gfs2_glock *gl = gh->gh_gl; |
| 970 | |
| 971 | spin_lock(&gl->gl_spin); |
| 972 | |
| 973 | while (gl->gl_req_gh != gh && |
| 974 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && |
| 975 | !list_empty(&gh->gh_list)) { |
Steven Whitehouse | 5029996 | 2006-09-04 09:49:55 -0400 | [diff] [blame] | 976 | if (gl->gl_req_bh && !(gl->gl_req_gh && |
| 977 | (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 978 | spin_unlock(&gl->gl_spin); |
| 979 | gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock); |
| 980 | msleep(100); |
| 981 | spin_lock(&gl->gl_spin); |
| 982 | } else { |
| 983 | spin_unlock(&gl->gl_spin); |
| 984 | msleep(100); |
| 985 | spin_lock(&gl->gl_spin); |
| 986 | } |
| 987 | } |
| 988 | |
| 989 | spin_unlock(&gl->gl_spin); |
| 990 | } |
| 991 | |
| 992 | /** |
| 993 | * glock_wait_internal - wait on a glock acquisition |
| 994 | * @gh: the glock holder |
| 995 | * |
| 996 | * Returns: 0 on success |
| 997 | */ |
| 998 | |
| 999 | static int glock_wait_internal(struct gfs2_holder *gh) |
| 1000 | { |
| 1001 | struct gfs2_glock *gl = gh->gh_gl; |
| 1002 | struct gfs2_sbd *sdp = gl->gl_sbd; |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 1003 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1004 | |
| 1005 | if (test_bit(HIF_ABORTED, &gh->gh_iflags)) |
| 1006 | return -EIO; |
| 1007 | |
| 1008 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
| 1009 | spin_lock(&gl->gl_spin); |
| 1010 | if (gl->gl_req_gh != gh && |
| 1011 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && |
| 1012 | !list_empty(&gh->gh_list)) { |
| 1013 | list_del_init(&gh->gh_list); |
| 1014 | gh->gh_error = GLR_TRYFAILED; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1015 | run_queue(gl); |
| 1016 | spin_unlock(&gl->gl_spin); |
| 1017 | return gh->gh_error; |
| 1018 | } |
| 1019 | spin_unlock(&gl->gl_spin); |
| 1020 | } |
| 1021 | |
| 1022 | if (gh->gh_flags & LM_FLAG_PRIORITY) |
| 1023 | do_cancels(gh); |
| 1024 | |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 1025 | wait_on_holder(gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1026 | if (gh->gh_error) |
| 1027 | return gh->gh_error; |
| 1028 | |
| 1029 | gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags)); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 1030 | gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, gh->gh_state, |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1031 | gh->gh_flags)); |
| 1032 | |
| 1033 | if (test_bit(HIF_FIRST, &gh->gh_iflags)) { |
| 1034 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
| 1035 | |
| 1036 | if (glops->go_lock) { |
| 1037 | gh->gh_error = glops->go_lock(gh); |
| 1038 | if (gh->gh_error) { |
| 1039 | spin_lock(&gl->gl_spin); |
| 1040 | list_del_init(&gh->gh_list); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1041 | spin_unlock(&gl->gl_spin); |
| 1042 | } |
| 1043 | } |
| 1044 | |
| 1045 | spin_lock(&gl->gl_spin); |
| 1046 | gl->gl_req_gh = NULL; |
| 1047 | gl->gl_req_bh = NULL; |
| 1048 | clear_bit(GLF_LOCK, &gl->gl_flags); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1049 | run_queue(gl); |
| 1050 | spin_unlock(&gl->gl_spin); |
| 1051 | } |
| 1052 | |
| 1053 | return gh->gh_error; |
| 1054 | } |
| 1055 | |
| 1056 | static inline struct gfs2_holder * |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1057 | find_holder_by_owner(struct list_head *head, pid_t pid) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1058 | { |
| 1059 | struct gfs2_holder *gh; |
| 1060 | |
| 1061 | list_for_each_entry(gh, head, gh_list) { |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1062 | if (gh->gh_owner_pid == pid) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1063 | return gh; |
| 1064 | } |
| 1065 | |
| 1066 | return NULL; |
| 1067 | } |
| 1068 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1069 | static void print_dbg(struct glock_iter *gi, const char *fmt, ...) |
| 1070 | { |
| 1071 | va_list args; |
| 1072 | |
| 1073 | va_start(args, fmt); |
| 1074 | if (gi) { |
| 1075 | vsprintf(gi->string, fmt, args); |
| 1076 | seq_printf(gi->seq, gi->string); |
| 1077 | } |
| 1078 | else |
| 1079 | vprintk(fmt, args); |
| 1080 | va_end(args); |
| 1081 | } |
| 1082 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1083 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1084 | * add_to_queue - Add a holder to the wait queue (but look for recursion) |
| 1085 | * @gh: the holder structure to add |
| 1086 | * |
| 1087 | */ |
| 1088 | |
| 1089 | static void add_to_queue(struct gfs2_holder *gh) |
| 1090 | { |
| 1091 | struct gfs2_glock *gl = gh->gh_gl; |
| 1092 | struct gfs2_holder *existing; |
| 1093 | |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1094 | BUG_ON(!gh->gh_owner_pid); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 1095 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
| 1096 | BUG(); |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 1097 | |
Abhijith Das | b4c2016 | 2007-09-13 23:35:27 -0500 | [diff] [blame] | 1098 | if (!(gh->gh_flags & GL_FLOCK)) { |
| 1099 | existing = find_holder_by_owner(&gl->gl_holders, |
| 1100 | gh->gh_owner_pid); |
| 1101 | if (existing) { |
| 1102 | print_symbol(KERN_WARNING "original: %s\n", |
| 1103 | existing->gh_ip); |
| 1104 | printk(KERN_INFO "pid : %d\n", existing->gh_owner_pid); |
| 1105 | printk(KERN_INFO "lock type : %d lock state : %d\n", |
| 1106 | existing->gh_gl->gl_name.ln_type, |
| 1107 | existing->gh_gl->gl_state); |
| 1108 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); |
| 1109 | printk(KERN_INFO "pid : %d\n", gh->gh_owner_pid); |
| 1110 | printk(KERN_INFO "lock type : %d lock state : %d\n", |
| 1111 | gl->gl_name.ln_type, gl->gl_state); |
| 1112 | BUG(); |
| 1113 | } |
| 1114 | |
| 1115 | existing = find_holder_by_owner(&gl->gl_waiters3, |
| 1116 | gh->gh_owner_pid); |
| 1117 | if (existing) { |
| 1118 | print_symbol(KERN_WARNING "original: %s\n", |
| 1119 | existing->gh_ip); |
| 1120 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); |
| 1121 | BUG(); |
| 1122 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1123 | } |
| 1124 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1125 | if (gh->gh_flags & LM_FLAG_PRIORITY) |
| 1126 | list_add(&gh->gh_list, &gl->gl_waiters3); |
| 1127 | else |
Steven Whitehouse | 907b9bc | 2006-09-25 09:26:04 -0400 | [diff] [blame] | 1128 | list_add_tail(&gh->gh_list, &gl->gl_waiters3); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1129 | } |
| 1130 | |
| 1131 | /** |
| 1132 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) |
| 1133 | * @gh: the holder structure |
| 1134 | * |
| 1135 | * if (gh->gh_flags & GL_ASYNC), this never returns an error |
| 1136 | * |
| 1137 | * Returns: 0, GLR_TRYFAILED, or errno on failure |
| 1138 | */ |
| 1139 | |
| 1140 | int gfs2_glock_nq(struct gfs2_holder *gh) |
| 1141 | { |
| 1142 | struct gfs2_glock *gl = gh->gh_gl; |
| 1143 | struct gfs2_sbd *sdp = gl->gl_sbd; |
| 1144 | int error = 0; |
| 1145 | |
Steven Whitehouse | 320dd10 | 2006-05-18 16:25:27 -0400 | [diff] [blame] | 1146 | restart: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1147 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
| 1148 | set_bit(HIF_ABORTED, &gh->gh_iflags); |
| 1149 | return -EIO; |
| 1150 | } |
| 1151 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1152 | spin_lock(&gl->gl_spin); |
| 1153 | add_to_queue(gh); |
| 1154 | run_queue(gl); |
| 1155 | spin_unlock(&gl->gl_spin); |
| 1156 | |
| 1157 | if (!(gh->gh_flags & GL_ASYNC)) { |
| 1158 | error = glock_wait_internal(gh); |
| 1159 | if (error == GLR_CANCELED) { |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 1160 | msleep(100); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1161 | goto restart; |
| 1162 | } |
| 1163 | } |
| 1164 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1165 | return error; |
| 1166 | } |
| 1167 | |
| 1168 | /** |
| 1169 | * gfs2_glock_poll - poll to see if an async request has been completed |
| 1170 | * @gh: the holder |
| 1171 | * |
| 1172 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on |
| 1173 | */ |
| 1174 | |
| 1175 | int gfs2_glock_poll(struct gfs2_holder *gh) |
| 1176 | { |
| 1177 | struct gfs2_glock *gl = gh->gh_gl; |
| 1178 | int ready = 0; |
| 1179 | |
| 1180 | spin_lock(&gl->gl_spin); |
| 1181 | |
| 1182 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) |
| 1183 | ready = 1; |
| 1184 | else if (list_empty(&gh->gh_list)) { |
| 1185 | if (gh->gh_error == GLR_CANCELED) { |
| 1186 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 1187 | msleep(100); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1188 | if (gfs2_glock_nq(gh)) |
| 1189 | return 1; |
| 1190 | return 0; |
| 1191 | } else |
| 1192 | ready = 1; |
| 1193 | } |
| 1194 | |
| 1195 | spin_unlock(&gl->gl_spin); |
| 1196 | |
| 1197 | return ready; |
| 1198 | } |
| 1199 | |
| 1200 | /** |
| 1201 | * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC |
| 1202 | * @gh: the holder structure |
| 1203 | * |
| 1204 | * Returns: 0, GLR_TRYFAILED, or errno on failure |
| 1205 | */ |
| 1206 | |
| 1207 | int gfs2_glock_wait(struct gfs2_holder *gh) |
| 1208 | { |
| 1209 | int error; |
| 1210 | |
| 1211 | error = glock_wait_internal(gh); |
| 1212 | if (error == GLR_CANCELED) { |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 1213 | msleep(100); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1214 | gh->gh_flags &= ~GL_ASYNC; |
| 1215 | error = gfs2_glock_nq(gh); |
| 1216 | } |
| 1217 | |
| 1218 | return error; |
| 1219 | } |
| 1220 | |
| 1221 | /** |
| 1222 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) |
| 1223 | * @gh: the glock holder |
| 1224 | * |
| 1225 | */ |
| 1226 | |
| 1227 | void gfs2_glock_dq(struct gfs2_holder *gh) |
| 1228 | { |
| 1229 | struct gfs2_glock *gl = gh->gh_gl; |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 1230 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1231 | unsigned delay = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1232 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1233 | if (gh->gh_flags & GL_NOCACHE) |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1234 | handle_callback(gl, LM_ST_UNLOCKED, 0, 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1235 | |
| 1236 | gfs2_glmutex_lock(gl); |
| 1237 | |
| 1238 | spin_lock(&gl->gl_spin); |
| 1239 | list_del_init(&gh->gh_list); |
| 1240 | |
| 1241 | if (list_empty(&gl->gl_holders)) { |
Steven Whitehouse | 3042a2c | 2007-11-02 08:39:34 +0000 | [diff] [blame] | 1242 | if (glops->go_unlock) { |
| 1243 | spin_unlock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1244 | glops->go_unlock(gh); |
Steven Whitehouse | 3042a2c | 2007-11-02 08:39:34 +0000 | [diff] [blame] | 1245 | spin_lock(&gl->gl_spin); |
| 1246 | } |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 1247 | gl->gl_stamp = jiffies; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1248 | } |
| 1249 | |
| 1250 | clear_bit(GLF_LOCK, &gl->gl_flags); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1251 | spin_unlock(&gl->gl_spin); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1252 | |
| 1253 | gfs2_glock_hold(gl); |
| 1254 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
| 1255 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) |
| 1256 | delay = gl->gl_ops->go_min_hold_time; |
| 1257 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
| 1258 | gfs2_glock_put(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1259 | } |
| 1260 | |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 1261 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
| 1262 | { |
| 1263 | struct gfs2_glock *gl = gh->gh_gl; |
| 1264 | gfs2_glock_dq(gh); |
| 1265 | wait_on_demote(gl); |
| 1266 | } |
| 1267 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1268 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1269 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it |
| 1270 | * @gh: the holder structure |
| 1271 | * |
| 1272 | */ |
| 1273 | |
| 1274 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) |
| 1275 | { |
| 1276 | gfs2_glock_dq(gh); |
| 1277 | gfs2_holder_uninit(gh); |
| 1278 | } |
| 1279 | |
| 1280 | /** |
| 1281 | * gfs2_glock_nq_num - acquire a glock based on lock number |
| 1282 | * @sdp: the filesystem |
| 1283 | * @number: the lock number |
| 1284 | * @glops: the glock operations for the type of glock |
| 1285 | * @state: the state to acquire the glock in |
| 1286 | * @flags: modifier flags for the aquisition |
| 1287 | * @gh: the struct gfs2_holder |
| 1288 | * |
| 1289 | * Returns: errno |
| 1290 | */ |
| 1291 | |
Steven Whitehouse | cd91549 | 2006-09-04 12:49:07 -0400 | [diff] [blame] | 1292 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 1293 | const struct gfs2_glock_operations *glops, |
| 1294 | unsigned int state, int flags, struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1295 | { |
| 1296 | struct gfs2_glock *gl; |
| 1297 | int error; |
| 1298 | |
| 1299 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); |
| 1300 | if (!error) { |
| 1301 | error = gfs2_glock_nq_init(gl, state, flags, gh); |
| 1302 | gfs2_glock_put(gl); |
| 1303 | } |
| 1304 | |
| 1305 | return error; |
| 1306 | } |
| 1307 | |
| 1308 | /** |
| 1309 | * glock_compare - Compare two struct gfs2_glock structures for sorting |
| 1310 | * @arg_a: the first structure |
| 1311 | * @arg_b: the second structure |
| 1312 | * |
| 1313 | */ |
| 1314 | |
| 1315 | static int glock_compare(const void *arg_a, const void *arg_b) |
| 1316 | { |
Steven Whitehouse | a5e08a9 | 2006-09-09 17:07:05 -0400 | [diff] [blame] | 1317 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
| 1318 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; |
| 1319 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; |
| 1320 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1321 | |
| 1322 | if (a->ln_number > b->ln_number) |
Steven Whitehouse | a5e08a9 | 2006-09-09 17:07:05 -0400 | [diff] [blame] | 1323 | return 1; |
| 1324 | if (a->ln_number < b->ln_number) |
| 1325 | return -1; |
Steven Whitehouse | 1c0f487 | 2007-01-22 12:10:39 -0500 | [diff] [blame] | 1326 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
Steven Whitehouse | a5e08a9 | 2006-09-09 17:07:05 -0400 | [diff] [blame] | 1327 | return 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1328 | } |
| 1329 | |
| 1330 | /** |
| 1331 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order |
| 1332 | * @num_gh: the number of structures |
| 1333 | * @ghs: an array of struct gfs2_holder structures |
| 1334 | * |
| 1335 | * Returns: 0 on success (all glocks acquired), |
| 1336 | * errno on failure (no glocks acquired) |
| 1337 | */ |
| 1338 | |
| 1339 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, |
| 1340 | struct gfs2_holder **p) |
| 1341 | { |
| 1342 | unsigned int x; |
| 1343 | int error = 0; |
| 1344 | |
| 1345 | for (x = 0; x < num_gh; x++) |
| 1346 | p[x] = &ghs[x]; |
| 1347 | |
| 1348 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); |
| 1349 | |
| 1350 | for (x = 0; x < num_gh; x++) { |
| 1351 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
| 1352 | |
| 1353 | error = gfs2_glock_nq(p[x]); |
| 1354 | if (error) { |
| 1355 | while (x--) |
| 1356 | gfs2_glock_dq(p[x]); |
| 1357 | break; |
| 1358 | } |
| 1359 | } |
| 1360 | |
| 1361 | return error; |
| 1362 | } |
| 1363 | |
| 1364 | /** |
| 1365 | * gfs2_glock_nq_m - acquire multiple glocks |
| 1366 | * @num_gh: the number of structures |
| 1367 | * @ghs: an array of struct gfs2_holder structures |
| 1368 | * |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1369 | * |
| 1370 | * Returns: 0 on success (all glocks acquired), |
| 1371 | * errno on failure (no glocks acquired) |
| 1372 | */ |
| 1373 | |
| 1374 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) |
| 1375 | { |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1376 | struct gfs2_holder *tmp[4]; |
| 1377 | struct gfs2_holder **pph = tmp; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1378 | int error = 0; |
| 1379 | |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1380 | switch(num_gh) { |
| 1381 | case 0: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1382 | return 0; |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1383 | case 1: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1384 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
| 1385 | return gfs2_glock_nq(ghs); |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1386 | default: |
| 1387 | if (num_gh <= 4) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1388 | break; |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1389 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
| 1390 | if (!pph) |
| 1391 | return -ENOMEM; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1392 | } |
| 1393 | |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1394 | error = nq_m_sync(num_gh, ghs, pph); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1395 | |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1396 | if (pph != tmp) |
| 1397 | kfree(pph); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1398 | |
| 1399 | return error; |
| 1400 | } |
| 1401 | |
| 1402 | /** |
| 1403 | * gfs2_glock_dq_m - release multiple glocks |
| 1404 | * @num_gh: the number of structures |
| 1405 | * @ghs: an array of struct gfs2_holder structures |
| 1406 | * |
| 1407 | */ |
| 1408 | |
| 1409 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) |
| 1410 | { |
| 1411 | unsigned int x; |
| 1412 | |
| 1413 | for (x = 0; x < num_gh; x++) |
| 1414 | gfs2_glock_dq(&ghs[x]); |
| 1415 | } |
| 1416 | |
| 1417 | /** |
| 1418 | * gfs2_glock_dq_uninit_m - release multiple glocks |
| 1419 | * @num_gh: the number of structures |
| 1420 | * @ghs: an array of struct gfs2_holder structures |
| 1421 | * |
| 1422 | */ |
| 1423 | |
| 1424 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) |
| 1425 | { |
| 1426 | unsigned int x; |
| 1427 | |
| 1428 | for (x = 0; x < num_gh; x++) |
| 1429 | gfs2_glock_dq_uninit(&ghs[x]); |
| 1430 | } |
| 1431 | |
| 1432 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1433 | * gfs2_lvb_hold - attach a LVB from a glock |
| 1434 | * @gl: The glock in question |
| 1435 | * |
| 1436 | */ |
| 1437 | |
| 1438 | int gfs2_lvb_hold(struct gfs2_glock *gl) |
| 1439 | { |
| 1440 | int error; |
| 1441 | |
| 1442 | gfs2_glmutex_lock(gl); |
| 1443 | |
| 1444 | if (!atomic_read(&gl->gl_lvb_count)) { |
| 1445 | error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); |
| 1446 | if (error) { |
| 1447 | gfs2_glmutex_unlock(gl); |
| 1448 | return error; |
| 1449 | } |
| 1450 | gfs2_glock_hold(gl); |
| 1451 | } |
| 1452 | atomic_inc(&gl->gl_lvb_count); |
| 1453 | |
| 1454 | gfs2_glmutex_unlock(gl); |
| 1455 | |
| 1456 | return 0; |
| 1457 | } |
| 1458 | |
| 1459 | /** |
| 1460 | * gfs2_lvb_unhold - detach a LVB from a glock |
| 1461 | * @gl: The glock in question |
| 1462 | * |
| 1463 | */ |
| 1464 | |
| 1465 | void gfs2_lvb_unhold(struct gfs2_glock *gl) |
| 1466 | { |
| 1467 | gfs2_glock_hold(gl); |
| 1468 | gfs2_glmutex_lock(gl); |
| 1469 | |
| 1470 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); |
| 1471 | if (atomic_dec_and_test(&gl->gl_lvb_count)) { |
| 1472 | gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); |
| 1473 | gl->gl_lvb = NULL; |
| 1474 | gfs2_glock_put(gl); |
| 1475 | } |
| 1476 | |
| 1477 | gfs2_glmutex_unlock(gl); |
| 1478 | gfs2_glock_put(gl); |
| 1479 | } |
| 1480 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1481 | static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, |
| 1482 | unsigned int state) |
| 1483 | { |
| 1484 | struct gfs2_glock *gl; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1485 | unsigned long delay = 0; |
| 1486 | unsigned long holdtime; |
| 1487 | unsigned long now = jiffies; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1488 | |
| 1489 | gl = gfs2_glock_find(sdp, name); |
| 1490 | if (!gl) |
| 1491 | return; |
| 1492 | |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1493 | holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time; |
| 1494 | if (time_before(now, holdtime)) |
| 1495 | delay = holdtime - now; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1496 | |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1497 | handle_callback(gl, state, 1, delay); |
| 1498 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
| 1499 | gfs2_glock_put(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1500 | } |
| 1501 | |
| 1502 | /** |
| 1503 | * gfs2_glock_cb - Callback used by locking module |
Steven Whitehouse | 1c089c3 | 2006-09-07 15:50:20 -0400 | [diff] [blame] | 1504 | * @sdp: Pointer to the superblock |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1505 | * @type: Type of callback |
| 1506 | * @data: Type dependent data pointer |
| 1507 | * |
| 1508 | * Called by the locking module when it wants to tell us something. |
| 1509 | * Either we need to drop a lock, one of our ASYNC requests completed, or |
| 1510 | * a journal from another client needs to be recovered. |
| 1511 | */ |
| 1512 | |
Steven Whitehouse | 9b47c11 | 2006-09-08 10:17:58 -0400 | [diff] [blame] | 1513 | void gfs2_glock_cb(void *cb_data, unsigned int type, void *data) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1514 | { |
Steven Whitehouse | 9b47c11 | 2006-09-08 10:17:58 -0400 | [diff] [blame] | 1515 | struct gfs2_sbd *sdp = cb_data; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1516 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1517 | switch (type) { |
| 1518 | case LM_CB_NEED_E: |
David Teigland | e7f5c01 | 2006-04-27 11:25:45 -0400 | [diff] [blame] | 1519 | blocking_cb(sdp, data, LM_ST_UNLOCKED); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1520 | return; |
| 1521 | |
| 1522 | case LM_CB_NEED_D: |
David Teigland | e7f5c01 | 2006-04-27 11:25:45 -0400 | [diff] [blame] | 1523 | blocking_cb(sdp, data, LM_ST_DEFERRED); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1524 | return; |
| 1525 | |
| 1526 | case LM_CB_NEED_S: |
David Teigland | e7f5c01 | 2006-04-27 11:25:45 -0400 | [diff] [blame] | 1527 | blocking_cb(sdp, data, LM_ST_SHARED); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1528 | return; |
| 1529 | |
| 1530 | case LM_CB_ASYNC: { |
David Teigland | e7f5c01 | 2006-04-27 11:25:45 -0400 | [diff] [blame] | 1531 | struct lm_async_cb *async = data; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1532 | struct gfs2_glock *gl; |
| 1533 | |
Steven Whitehouse | 61be084 | 2007-01-29 11:51:45 +0000 | [diff] [blame] | 1534 | down_read(&gfs2_umount_flush_sem); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1535 | gl = gfs2_glock_find(sdp, &async->lc_name); |
| 1536 | if (gfs2_assert_warn(sdp, gl)) |
| 1537 | return; |
| 1538 | if (!gfs2_assert_warn(sdp, gl->gl_req_bh)) |
| 1539 | gl->gl_req_bh(gl, async->lc_ret); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1540 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
| 1541 | gfs2_glock_put(gl); |
Steven Whitehouse | 61be084 | 2007-01-29 11:51:45 +0000 | [diff] [blame] | 1542 | up_read(&gfs2_umount_flush_sem); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1543 | return; |
| 1544 | } |
| 1545 | |
| 1546 | case LM_CB_NEED_RECOVERY: |
| 1547 | gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); |
| 1548 | if (sdp->sd_recoverd_process) |
| 1549 | wake_up_process(sdp->sd_recoverd_process); |
| 1550 | return; |
| 1551 | |
| 1552 | case LM_CB_DROPLOCKS: |
| 1553 | gfs2_gl_hash_clear(sdp, NO_WAIT); |
| 1554 | gfs2_quota_scan(sdp); |
| 1555 | return; |
| 1556 | |
| 1557 | default: |
| 1558 | gfs2_assert_warn(sdp, 0); |
| 1559 | return; |
| 1560 | } |
| 1561 | } |
| 1562 | |
| 1563 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1564 | * demote_ok - Check to see if it's ok to unlock a glock |
| 1565 | * @gl: the glock |
| 1566 | * |
| 1567 | * Returns: 1 if it's ok |
| 1568 | */ |
| 1569 | |
| 1570 | static int demote_ok(struct gfs2_glock *gl) |
| 1571 | { |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 1572 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1573 | int demote = 1; |
| 1574 | |
| 1575 | if (test_bit(GLF_STICKY, &gl->gl_flags)) |
| 1576 | demote = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1577 | else if (glops->go_demote_ok) |
| 1578 | demote = glops->go_demote_ok(gl); |
| 1579 | |
| 1580 | return demote; |
| 1581 | } |
| 1582 | |
| 1583 | /** |
| 1584 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list |
| 1585 | * @gl: the glock |
| 1586 | * |
| 1587 | */ |
| 1588 | |
| 1589 | void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) |
| 1590 | { |
| 1591 | struct gfs2_sbd *sdp = gl->gl_sbd; |
| 1592 | |
| 1593 | spin_lock(&sdp->sd_reclaim_lock); |
| 1594 | if (list_empty(&gl->gl_reclaim)) { |
| 1595 | gfs2_glock_hold(gl); |
| 1596 | list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list); |
| 1597 | atomic_inc(&sdp->sd_reclaim_count); |
| 1598 | } |
| 1599 | spin_unlock(&sdp->sd_reclaim_lock); |
| 1600 | |
| 1601 | wake_up(&sdp->sd_reclaim_wq); |
| 1602 | } |
| 1603 | |
| 1604 | /** |
| 1605 | * gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list |
| 1606 | * @sdp: the filesystem |
| 1607 | * |
| 1608 | * Called from gfs2_glockd() glock reclaim daemon, or when promoting a |
| 1609 | * different glock and we notice that there are a lot of glocks in the |
| 1610 | * reclaim list. |
| 1611 | * |
| 1612 | */ |
| 1613 | |
| 1614 | void gfs2_reclaim_glock(struct gfs2_sbd *sdp) |
| 1615 | { |
| 1616 | struct gfs2_glock *gl; |
| 1617 | |
| 1618 | spin_lock(&sdp->sd_reclaim_lock); |
| 1619 | if (list_empty(&sdp->sd_reclaim_list)) { |
| 1620 | spin_unlock(&sdp->sd_reclaim_lock); |
| 1621 | return; |
| 1622 | } |
| 1623 | gl = list_entry(sdp->sd_reclaim_list.next, |
| 1624 | struct gfs2_glock, gl_reclaim); |
| 1625 | list_del_init(&gl->gl_reclaim); |
| 1626 | spin_unlock(&sdp->sd_reclaim_lock); |
| 1627 | |
| 1628 | atomic_dec(&sdp->sd_reclaim_count); |
| 1629 | atomic_inc(&sdp->sd_reclaimed); |
| 1630 | |
| 1631 | if (gfs2_glmutex_trylock(gl)) { |
Steven Whitehouse | 1213293 | 2007-01-22 13:09:04 -0500 | [diff] [blame] | 1632 | if (list_empty(&gl->gl_holders) && |
Steven Whitehouse | 5029996 | 2006-09-04 09:49:55 -0400 | [diff] [blame] | 1633 | gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl)) |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1634 | handle_callback(gl, LM_ST_UNLOCKED, 0, 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1635 | gfs2_glmutex_unlock(gl); |
| 1636 | } |
| 1637 | |
| 1638 | gfs2_glock_put(gl); |
| 1639 | } |
| 1640 | |
| 1641 | /** |
| 1642 | * examine_bucket - Call a function for glock in a hash bucket |
| 1643 | * @examiner: the function |
| 1644 | * @sdp: the filesystem |
| 1645 | * @bucket: the bucket |
| 1646 | * |
| 1647 | * Returns: 1 if the bucket has entries |
| 1648 | */ |
| 1649 | |
| 1650 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 1651 | unsigned int hash) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1652 | { |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1653 | struct gfs2_glock *gl, *prev = NULL; |
| 1654 | int has_entries = 0; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1655 | struct hlist_head *head = &gl_hash_table[hash].hb_list; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1656 | |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1657 | read_lock(gl_lock_addr(hash)); |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1658 | /* Can't use hlist_for_each_entry - don't want prefetch here */ |
| 1659 | if (hlist_empty(head)) |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1660 | goto out; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1661 | gl = list_entry(head->first, struct gfs2_glock, gl_list); |
| 1662 | while(1) { |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1663 | if (!sdp || gl->gl_sbd == sdp) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1664 | gfs2_glock_hold(gl); |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1665 | read_unlock(gl_lock_addr(hash)); |
| 1666 | if (prev) |
| 1667 | gfs2_glock_put(prev); |
| 1668 | prev = gl; |
| 1669 | examiner(gl); |
Steven Whitehouse | a833634 | 2006-09-14 13:57:38 -0400 | [diff] [blame] | 1670 | has_entries = 1; |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1671 | read_lock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1672 | } |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1673 | if (gl->gl_list.next == NULL) |
| 1674 | break; |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1675 | gl = list_entry(gl->gl_list.next, struct gfs2_glock, gl_list); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1676 | } |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1677 | out: |
| 1678 | read_unlock(gl_lock_addr(hash)); |
| 1679 | if (prev) |
| 1680 | gfs2_glock_put(prev); |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1681 | cond_resched(); |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1682 | return has_entries; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1683 | } |
| 1684 | |
| 1685 | /** |
| 1686 | * scan_glock - look at a glock and see if we can reclaim it |
| 1687 | * @gl: the glock to look at |
| 1688 | * |
| 1689 | */ |
| 1690 | |
| 1691 | static void scan_glock(struct gfs2_glock *gl) |
| 1692 | { |
Steven Whitehouse | b004157 | 2006-11-23 10:51:34 -0500 | [diff] [blame] | 1693 | if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1694 | return; |
Steven Whitehouse | a2242db | 2006-08-24 17:03:05 -0400 | [diff] [blame] | 1695 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1696 | if (gfs2_glmutex_trylock(gl)) { |
Steven Whitehouse | 1213293 | 2007-01-22 13:09:04 -0500 | [diff] [blame] | 1697 | if (list_empty(&gl->gl_holders) && |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1698 | gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl)) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1699 | goto out_schedule; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1700 | gfs2_glmutex_unlock(gl); |
| 1701 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1702 | return; |
| 1703 | |
Steven Whitehouse | 627add2 | 2006-07-05 13:16:19 -0400 | [diff] [blame] | 1704 | out_schedule: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1705 | gfs2_glmutex_unlock(gl); |
| 1706 | gfs2_glock_schedule_for_reclaim(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1707 | } |
| 1708 | |
| 1709 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1710 | * clear_glock - look at a glock and see if we can free it from glock cache |
| 1711 | * @gl: the glock to look at |
| 1712 | * |
| 1713 | */ |
| 1714 | |
| 1715 | static void clear_glock(struct gfs2_glock *gl) |
| 1716 | { |
| 1717 | struct gfs2_sbd *sdp = gl->gl_sbd; |
| 1718 | int released; |
| 1719 | |
| 1720 | spin_lock(&sdp->sd_reclaim_lock); |
| 1721 | if (!list_empty(&gl->gl_reclaim)) { |
| 1722 | list_del_init(&gl->gl_reclaim); |
| 1723 | atomic_dec(&sdp->sd_reclaim_count); |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 1724 | spin_unlock(&sdp->sd_reclaim_lock); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1725 | released = gfs2_glock_put(gl); |
| 1726 | gfs2_assert(sdp, !released); |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 1727 | } else { |
| 1728 | spin_unlock(&sdp->sd_reclaim_lock); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1729 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1730 | |
| 1731 | if (gfs2_glmutex_trylock(gl)) { |
Steven Whitehouse | 90101c3 | 2007-01-23 13:20:41 -0500 | [diff] [blame] | 1732 | if (list_empty(&gl->gl_holders) && |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1733 | gl->gl_state != LM_ST_UNLOCKED) |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1734 | handle_callback(gl, LM_ST_UNLOCKED, 0, 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1735 | gfs2_glmutex_unlock(gl); |
| 1736 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1737 | } |
| 1738 | |
| 1739 | /** |
| 1740 | * gfs2_gl_hash_clear - Empty out the glock hash table |
| 1741 | * @sdp: the filesystem |
| 1742 | * @wait: wait until it's all gone |
| 1743 | * |
| 1744 | * Called when unmounting the filesystem, or when inter-node lock manager |
| 1745 | * requests DROPLOCKS because it is running out of capacity. |
| 1746 | */ |
| 1747 | |
| 1748 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait) |
| 1749 | { |
| 1750 | unsigned long t; |
| 1751 | unsigned int x; |
| 1752 | int cont; |
| 1753 | |
| 1754 | t = jiffies; |
| 1755 | |
| 1756 | for (;;) { |
| 1757 | cont = 0; |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1758 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { |
Steven Whitehouse | 907b9bc | 2006-09-25 09:26:04 -0400 | [diff] [blame] | 1759 | if (examine_bucket(clear_glock, sdp, x)) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1760 | cont = 1; |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1761 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1762 | |
| 1763 | if (!wait || !cont) |
| 1764 | break; |
| 1765 | |
| 1766 | if (time_after_eq(jiffies, |
| 1767 | t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) { |
| 1768 | fs_warn(sdp, "Unmount seems to be stalled. " |
| 1769 | "Dumping lock state...\n"); |
| 1770 | gfs2_dump_lockstate(sdp); |
| 1771 | t = jiffies; |
| 1772 | } |
| 1773 | |
Steven Whitehouse | 61be084 | 2007-01-29 11:51:45 +0000 | [diff] [blame] | 1774 | down_write(&gfs2_umount_flush_sem); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1775 | invalidate_inodes(sdp->sd_vfs); |
Steven Whitehouse | 61be084 | 2007-01-29 11:51:45 +0000 | [diff] [blame] | 1776 | up_write(&gfs2_umount_flush_sem); |
Steven Whitehouse | fd88de56 | 2006-05-05 16:59:11 -0400 | [diff] [blame] | 1777 | msleep(10); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1778 | } |
| 1779 | } |
| 1780 | |
| 1781 | /* |
| 1782 | * Diagnostic routines to help debug distributed deadlock |
| 1783 | */ |
| 1784 | |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1785 | static void gfs2_print_symbol(struct glock_iter *gi, const char *fmt, |
| 1786 | unsigned long address) |
| 1787 | { |
Robert Peterson | 7a0079d | 2007-04-17 11:37:11 -0500 | [diff] [blame] | 1788 | char buffer[KSYM_SYMBOL_LEN]; |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1789 | |
Robert Peterson | 7a0079d | 2007-04-17 11:37:11 -0500 | [diff] [blame] | 1790 | sprint_symbol(buffer, address); |
| 1791 | print_dbg(gi, fmt, buffer); |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1792 | } |
| 1793 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1794 | /** |
| 1795 | * dump_holder - print information about a glock holder |
| 1796 | * @str: a string naming the type of holder |
| 1797 | * @gh: the glock holder |
| 1798 | * |
| 1799 | * Returns: 0 on success, -ENOBUFS when we run out of space |
| 1800 | */ |
| 1801 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1802 | static int dump_holder(struct glock_iter *gi, char *str, |
| 1803 | struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1804 | { |
| 1805 | unsigned int x; |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1806 | struct task_struct *gh_owner; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1807 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1808 | print_dbg(gi, " %s\n", str); |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1809 | if (gh->gh_owner_pid) { |
| 1810 | print_dbg(gi, " owner = %ld ", (long)gh->gh_owner_pid); |
| 1811 | gh_owner = find_task_by_pid(gh->gh_owner_pid); |
| 1812 | if (gh_owner) |
| 1813 | print_dbg(gi, "(%s)\n", gh_owner->comm); |
| 1814 | else |
| 1815 | print_dbg(gi, "(ended)\n"); |
| 1816 | } else |
| 1817 | print_dbg(gi, " owner = -1\n"); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1818 | print_dbg(gi, " gh_state = %u\n", gh->gh_state); |
| 1819 | print_dbg(gi, " gh_flags ="); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1820 | for (x = 0; x < 32; x++) |
| 1821 | if (gh->gh_flags & (1 << x)) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1822 | print_dbg(gi, " %u", x); |
| 1823 | print_dbg(gi, " \n"); |
| 1824 | print_dbg(gi, " error = %d\n", gh->gh_error); |
| 1825 | print_dbg(gi, " gh_iflags ="); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1826 | for (x = 0; x < 32; x++) |
| 1827 | if (test_bit(x, &gh->gh_iflags)) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1828 | print_dbg(gi, " %u", x); |
| 1829 | print_dbg(gi, " \n"); |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1830 | gfs2_print_symbol(gi, " initialized at: %s\n", gh->gh_ip); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1831 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1832 | return 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1833 | } |
| 1834 | |
| 1835 | /** |
| 1836 | * dump_inode - print information about an inode |
| 1837 | * @ip: the inode |
| 1838 | * |
| 1839 | * Returns: 0 on success, -ENOBUFS when we run out of space |
| 1840 | */ |
| 1841 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1842 | static int dump_inode(struct glock_iter *gi, struct gfs2_inode *ip) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1843 | { |
| 1844 | unsigned int x; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1845 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1846 | print_dbg(gi, " Inode:\n"); |
| 1847 | print_dbg(gi, " num = %llu/%llu\n", |
Steven Whitehouse | dbb7cae | 2007-05-15 15:37:50 +0100 | [diff] [blame] | 1848 | (unsigned long long)ip->i_no_formal_ino, |
| 1849 | (unsigned long long)ip->i_no_addr); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1850 | print_dbg(gi, " type = %u\n", IF2DT(ip->i_inode.i_mode)); |
| 1851 | print_dbg(gi, " i_flags ="); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1852 | for (x = 0; x < 32; x++) |
| 1853 | if (test_bit(x, &ip->i_flags)) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1854 | print_dbg(gi, " %u", x); |
| 1855 | print_dbg(gi, " \n"); |
| 1856 | return 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1857 | } |
| 1858 | |
| 1859 | /** |
| 1860 | * dump_glock - print information about a glock |
| 1861 | * @gl: the glock |
| 1862 | * @count: where we are in the buffer |
| 1863 | * |
| 1864 | * Returns: 0 on success, -ENOBUFS when we run out of space |
| 1865 | */ |
| 1866 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1867 | static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1868 | { |
| 1869 | struct gfs2_holder *gh; |
| 1870 | unsigned int x; |
| 1871 | int error = -ENOBUFS; |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1872 | struct task_struct *gl_owner; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1873 | |
| 1874 | spin_lock(&gl->gl_spin); |
| 1875 | |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 1876 | print_dbg(gi, "Glock 0x%p (%u, 0x%llx)\n", gl, gl->gl_name.ln_type, |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1877 | (unsigned long long)gl->gl_name.ln_number); |
| 1878 | print_dbg(gi, " gl_flags ="); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 1879 | for (x = 0; x < 32; x++) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1880 | if (test_bit(x, &gl->gl_flags)) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1881 | print_dbg(gi, " %u", x); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 1882 | } |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1883 | if (!test_bit(GLF_LOCK, &gl->gl_flags)) |
| 1884 | print_dbg(gi, " (unlocked)"); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1885 | print_dbg(gi, " \n"); |
| 1886 | print_dbg(gi, " gl_ref = %d\n", atomic_read(&gl->gl_ref)); |
| 1887 | print_dbg(gi, " gl_state = %u\n", gl->gl_state); |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1888 | if (gl->gl_owner_pid) { |
| 1889 | gl_owner = find_task_by_pid(gl->gl_owner_pid); |
| 1890 | if (gl_owner) |
| 1891 | print_dbg(gi, " gl_owner = pid %d (%s)\n", |
| 1892 | gl->gl_owner_pid, gl_owner->comm); |
| 1893 | else |
| 1894 | print_dbg(gi, " gl_owner = %d (ended)\n", |
| 1895 | gl->gl_owner_pid); |
| 1896 | } else |
| 1897 | print_dbg(gi, " gl_owner = -1\n"); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1898 | print_dbg(gi, " gl_ip = %lu\n", gl->gl_ip); |
| 1899 | print_dbg(gi, " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no"); |
| 1900 | print_dbg(gi, " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no"); |
| 1901 | print_dbg(gi, " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count)); |
| 1902 | print_dbg(gi, " object = %s\n", (gl->gl_object) ? "yes" : "no"); |
| 1903 | print_dbg(gi, " le = %s\n", |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1904 | (list_empty(&gl->gl_le.le_list)) ? "no" : "yes"); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1905 | print_dbg(gi, " reclaim = %s\n", |
| 1906 | (list_empty(&gl->gl_reclaim)) ? "no" : "yes"); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1907 | if (gl->gl_aspace) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1908 | print_dbg(gi, " aspace = 0x%p nrpages = %lu\n", gl->gl_aspace, |
| 1909 | gl->gl_aspace->i_mapping->nrpages); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1910 | else |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1911 | print_dbg(gi, " aspace = no\n"); |
| 1912 | print_dbg(gi, " ail = %d\n", atomic_read(&gl->gl_ail_count)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1913 | if (gl->gl_req_gh) { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1914 | error = dump_holder(gi, "Request", gl->gl_req_gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1915 | if (error) |
| 1916 | goto out; |
| 1917 | } |
| 1918 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1919 | error = dump_holder(gi, "Holder", gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1920 | if (error) |
| 1921 | goto out; |
| 1922 | } |
| 1923 | list_for_each_entry(gh, &gl->gl_waiters1, gh_list) { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1924 | error = dump_holder(gi, "Waiter1", gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1925 | if (error) |
| 1926 | goto out; |
| 1927 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1928 | list_for_each_entry(gh, &gl->gl_waiters3, gh_list) { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1929 | error = dump_holder(gi, "Waiter3", gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1930 | if (error) |
| 1931 | goto out; |
| 1932 | } |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 1933 | if (test_bit(GLF_DEMOTE, &gl->gl_flags)) { |
| 1934 | print_dbg(gi, " Demotion req to state %u (%llu uS ago)\n", |
Robert Peterson | cd81a4b | 2007-05-14 12:42:18 -0500 | [diff] [blame] | 1935 | gl->gl_demote_state, (unsigned long long) |
| 1936 | (jiffies - gl->gl_demote_time)*(1000000/HZ)); |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 1937 | } |
Steven Whitehouse | 5c676f6 | 2006-02-27 17:23:27 -0500 | [diff] [blame] | 1938 | if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1939 | if (!test_bit(GLF_LOCK, &gl->gl_flags) && |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1940 | list_empty(&gl->gl_holders)) { |
| 1941 | error = dump_inode(gi, gl->gl_object); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1942 | if (error) |
| 1943 | goto out; |
| 1944 | } else { |
| 1945 | error = -ENOBUFS; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1946 | print_dbg(gi, " Inode: busy\n"); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1947 | } |
| 1948 | } |
| 1949 | |
| 1950 | error = 0; |
| 1951 | |
Steven Whitehouse | a91ea69 | 2006-09-04 12:04:26 -0400 | [diff] [blame] | 1952 | out: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1953 | spin_unlock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1954 | return error; |
| 1955 | } |
| 1956 | |
| 1957 | /** |
| 1958 | * gfs2_dump_lockstate - print out the current lockstate |
| 1959 | * @sdp: the filesystem |
| 1960 | * @ub: the buffer to copy the information into |
| 1961 | * |
| 1962 | * If @ub is NULL, dump the lockstate to the console. |
| 1963 | * |
| 1964 | */ |
| 1965 | |
Adrian Bunk | 08bc2db | 2006-04-28 10:59:12 -0400 | [diff] [blame] | 1966 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1967 | { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1968 | struct gfs2_glock *gl; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1969 | struct hlist_node *h; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1970 | unsigned int x; |
| 1971 | int error = 0; |
| 1972 | |
| 1973 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1974 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 1975 | read_lock(gl_lock_addr(x)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1976 | |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1977 | hlist_for_each_entry(gl, h, &gl_hash_table[x].hb_list, gl_list) { |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 1978 | if (gl->gl_sbd != sdp) |
| 1979 | continue; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1980 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1981 | error = dump_glock(NULL, gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1982 | if (error) |
| 1983 | break; |
| 1984 | } |
| 1985 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 1986 | read_unlock(gl_lock_addr(x)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1987 | |
| 1988 | if (error) |
| 1989 | break; |
| 1990 | } |
| 1991 | |
| 1992 | |
| 1993 | return error; |
| 1994 | } |
| 1995 | |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1996 | /** |
| 1997 | * gfs2_scand - Look for cached glocks and inodes to toss from memory |
| 1998 | * @sdp: Pointer to GFS2 superblock |
| 1999 | * |
| 2000 | * One of these daemons runs, finding candidates to add to sd_reclaim_list. |
| 2001 | * See gfs2_glockd() |
| 2002 | */ |
| 2003 | |
| 2004 | static int gfs2_scand(void *data) |
| 2005 | { |
| 2006 | unsigned x; |
| 2007 | unsigned delay; |
| 2008 | |
| 2009 | while (!kthread_should_stop()) { |
| 2010 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) |
| 2011 | examine_bucket(scan_glock, NULL, x); |
| 2012 | if (freezing(current)) |
| 2013 | refrigerator(); |
| 2014 | delay = scand_secs; |
| 2015 | if (delay < 1) |
| 2016 | delay = 1; |
| 2017 | schedule_timeout_interruptible(delay * HZ); |
| 2018 | } |
| 2019 | |
| 2020 | return 0; |
| 2021 | } |
| 2022 | |
| 2023 | |
| 2024 | |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 2025 | int __init gfs2_glock_init(void) |
| 2026 | { |
| 2027 | unsigned i; |
| 2028 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 2029 | INIT_HLIST_HEAD(&gl_hash_table[i].hb_list); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 2030 | } |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 2031 | #ifdef GL_HASH_LOCK_SZ |
| 2032 | for(i = 0; i < GL_HASH_LOCK_SZ; i++) { |
| 2033 | rwlock_init(&gl_hash_locks[i]); |
| 2034 | } |
| 2035 | #endif |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 2036 | |
| 2037 | scand_process = kthread_run(gfs2_scand, NULL, "gfs2_scand"); |
| 2038 | if (IS_ERR(scand_process)) |
| 2039 | return PTR_ERR(scand_process); |
| 2040 | |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 2041 | glock_workqueue = create_workqueue("glock_workqueue"); |
| 2042 | if (IS_ERR(glock_workqueue)) { |
| 2043 | kthread_stop(scand_process); |
| 2044 | return PTR_ERR(glock_workqueue); |
| 2045 | } |
| 2046 | |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 2047 | return 0; |
| 2048 | } |
| 2049 | |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 2050 | void gfs2_glock_exit(void) |
| 2051 | { |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 2052 | destroy_workqueue(glock_workqueue); |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 2053 | kthread_stop(scand_process); |
| 2054 | } |
| 2055 | |
| 2056 | module_param(scand_secs, uint, S_IRUGO|S_IWUSR); |
| 2057 | MODULE_PARM_DESC(scand_secs, "The number of seconds between scand runs"); |
| 2058 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2059 | static int gfs2_glock_iter_next(struct glock_iter *gi) |
| 2060 | { |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2061 | struct gfs2_glock *gl; |
| 2062 | |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2063 | restart: |
Robert Peterson | 7a0079d | 2007-04-17 11:37:11 -0500 | [diff] [blame] | 2064 | read_lock(gl_lock_addr(gi->hash)); |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2065 | gl = gi->gl; |
| 2066 | if (gl) { |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2067 | gi->gl = hlist_entry(gl->gl_list.next, |
| 2068 | struct gfs2_glock, gl_list); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2069 | if (gi->gl) |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2070 | gfs2_glock_hold(gi->gl); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2071 | } |
Robert Peterson | 7a0079d | 2007-04-17 11:37:11 -0500 | [diff] [blame] | 2072 | read_unlock(gl_lock_addr(gi->hash)); |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2073 | if (gl) |
| 2074 | gfs2_glock_put(gl); |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2075 | if (gl && gi->gl == NULL) |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2076 | gi->hash++; |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2077 | while(gi->gl == NULL) { |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2078 | if (gi->hash >= GFS2_GL_HASH_SIZE) |
| 2079 | return 1; |
| 2080 | read_lock(gl_lock_addr(gi->hash)); |
| 2081 | gi->gl = hlist_entry(gl_hash_table[gi->hash].hb_list.first, |
| 2082 | struct gfs2_glock, gl_list); |
| 2083 | if (gi->gl) |
| 2084 | gfs2_glock_hold(gi->gl); |
| 2085 | read_unlock(gl_lock_addr(gi->hash)); |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2086 | gi->hash++; |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2087 | } |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2088 | |
| 2089 | if (gi->sdp != gi->gl->gl_sbd) |
| 2090 | goto restart; |
| 2091 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2092 | return 0; |
| 2093 | } |
| 2094 | |
| 2095 | static void gfs2_glock_iter_free(struct glock_iter *gi) |
| 2096 | { |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2097 | if (gi->gl) |
| 2098 | gfs2_glock_put(gi->gl); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2099 | kfree(gi); |
| 2100 | } |
| 2101 | |
| 2102 | static struct glock_iter *gfs2_glock_iter_init(struct gfs2_sbd *sdp) |
| 2103 | { |
| 2104 | struct glock_iter *gi; |
| 2105 | |
| 2106 | gi = kmalloc(sizeof (*gi), GFP_KERNEL); |
| 2107 | if (!gi) |
| 2108 | return NULL; |
| 2109 | |
| 2110 | gi->sdp = sdp; |
| 2111 | gi->hash = 0; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2112 | gi->seq = NULL; |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2113 | gi->gl = NULL; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2114 | memset(gi->string, 0, sizeof(gi->string)); |
| 2115 | |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 2116 | if (gfs2_glock_iter_next(gi)) { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2117 | gfs2_glock_iter_free(gi); |
| 2118 | return NULL; |
| 2119 | } |
| 2120 | |
| 2121 | return gi; |
| 2122 | } |
| 2123 | |
| 2124 | static void *gfs2_glock_seq_start(struct seq_file *file, loff_t *pos) |
| 2125 | { |
| 2126 | struct glock_iter *gi; |
| 2127 | loff_t n = *pos; |
| 2128 | |
| 2129 | gi = gfs2_glock_iter_init(file->private); |
| 2130 | if (!gi) |
| 2131 | return NULL; |
| 2132 | |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2133 | while(n--) { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2134 | if (gfs2_glock_iter_next(gi)) { |
| 2135 | gfs2_glock_iter_free(gi); |
| 2136 | return NULL; |
| 2137 | } |
| 2138 | } |
| 2139 | |
| 2140 | return gi; |
| 2141 | } |
| 2142 | |
| 2143 | static void *gfs2_glock_seq_next(struct seq_file *file, void *iter_ptr, |
| 2144 | loff_t *pos) |
| 2145 | { |
| 2146 | struct glock_iter *gi = iter_ptr; |
| 2147 | |
| 2148 | (*pos)++; |
| 2149 | |
| 2150 | if (gfs2_glock_iter_next(gi)) { |
| 2151 | gfs2_glock_iter_free(gi); |
| 2152 | return NULL; |
| 2153 | } |
| 2154 | |
| 2155 | return gi; |
| 2156 | } |
| 2157 | |
| 2158 | static void gfs2_glock_seq_stop(struct seq_file *file, void *iter_ptr) |
| 2159 | { |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 2160 | struct glock_iter *gi = iter_ptr; |
| 2161 | if (gi) |
| 2162 | gfs2_glock_iter_free(gi); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2163 | } |
| 2164 | |
| 2165 | static int gfs2_glock_seq_show(struct seq_file *file, void *iter_ptr) |
| 2166 | { |
| 2167 | struct glock_iter *gi = iter_ptr; |
| 2168 | |
| 2169 | gi->seq = file; |
| 2170 | dump_glock(gi, gi->gl); |
| 2171 | |
| 2172 | return 0; |
| 2173 | } |
| 2174 | |
Denis Cheng | 4ef2900 | 2007-07-31 18:31:11 +0800 | [diff] [blame] | 2175 | static const struct seq_operations gfs2_glock_seq_ops = { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2176 | .start = gfs2_glock_seq_start, |
| 2177 | .next = gfs2_glock_seq_next, |
| 2178 | .stop = gfs2_glock_seq_stop, |
| 2179 | .show = gfs2_glock_seq_show, |
| 2180 | }; |
| 2181 | |
| 2182 | static int gfs2_debugfs_open(struct inode *inode, struct file *file) |
| 2183 | { |
| 2184 | struct seq_file *seq; |
| 2185 | int ret; |
| 2186 | |
| 2187 | ret = seq_open(file, &gfs2_glock_seq_ops); |
| 2188 | if (ret) |
| 2189 | return ret; |
| 2190 | |
| 2191 | seq = file->private_data; |
| 2192 | seq->private = inode->i_private; |
| 2193 | |
| 2194 | return 0; |
| 2195 | } |
| 2196 | |
| 2197 | static const struct file_operations gfs2_debug_fops = { |
| 2198 | .owner = THIS_MODULE, |
| 2199 | .open = gfs2_debugfs_open, |
| 2200 | .read = seq_read, |
| 2201 | .llseek = seq_lseek, |
| 2202 | .release = seq_release |
| 2203 | }; |
| 2204 | |
| 2205 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) |
| 2206 | { |
Robert Peterson | 5f88209 | 2007-04-18 11:41:11 -0500 | [diff] [blame] | 2207 | sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root); |
| 2208 | if (!sdp->debugfs_dir) |
| 2209 | return -ENOMEM; |
| 2210 | sdp->debugfs_dentry_glocks = debugfs_create_file("glocks", |
| 2211 | S_IFREG | S_IRUGO, |
| 2212 | sdp->debugfs_dir, sdp, |
| 2213 | &gfs2_debug_fops); |
| 2214 | if (!sdp->debugfs_dentry_glocks) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2215 | return -ENOMEM; |
| 2216 | |
| 2217 | return 0; |
| 2218 | } |
| 2219 | |
| 2220 | void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp) |
| 2221 | { |
Robert Peterson | 5f88209 | 2007-04-18 11:41:11 -0500 | [diff] [blame] | 2222 | if (sdp && sdp->debugfs_dir) { |
| 2223 | if (sdp->debugfs_dentry_glocks) { |
| 2224 | debugfs_remove(sdp->debugfs_dentry_glocks); |
| 2225 | sdp->debugfs_dentry_glocks = NULL; |
| 2226 | } |
| 2227 | debugfs_remove(sdp->debugfs_dir); |
| 2228 | sdp->debugfs_dir = NULL; |
| 2229 | } |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2230 | } |
| 2231 | |
| 2232 | int gfs2_register_debugfs(void) |
| 2233 | { |
| 2234 | gfs2_root = debugfs_create_dir("gfs2", NULL); |
| 2235 | return gfs2_root ? 0 : -ENOMEM; |
| 2236 | } |
| 2237 | |
| 2238 | void gfs2_unregister_debugfs(void) |
| 2239 | { |
| 2240 | debugfs_remove(gfs2_root); |
Robert Peterson | 5f88209 | 2007-04-18 11:41:11 -0500 | [diff] [blame] | 2241 | gfs2_root = NULL; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 2242 | } |