David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. |
Bob Peterson | cf45b75 | 2008-01-31 10:31:39 -0600 | [diff] [blame] | 3 | * Copyright (C) 2004-2008 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> |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 13 | #include <linux/buffer_head.h> |
| 14 | #include <linux/delay.h> |
| 15 | #include <linux/sort.h> |
| 16 | #include <linux/jhash.h> |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 17 | #include <linux/kallsyms.h> |
Steven Whitehouse | 5c676f6 | 2006-02-27 17:23:27 -0500 | [diff] [blame] | 18 | #include <linux/gfs2_ondisk.h> |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 19 | #include <linux/list.h> |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 20 | #include <linux/wait.h> |
akpm@linux-foundation.org | 95d97b7 | 2007-03-05 23:10:39 -0800 | [diff] [blame] | 21 | #include <linux/module.h> |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 22 | #include <asm/uaccess.h> |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 23 | #include <linux/seq_file.h> |
| 24 | #include <linux/debugfs.h> |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 25 | #include <linux/kthread.h> |
| 26 | #include <linux/freezer.h> |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 27 | #include <linux/workqueue.h> |
| 28 | #include <linux/jiffies.h> |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 29 | |
| 30 | #include "gfs2.h" |
Steven Whitehouse | 5c676f6 | 2006-02-27 17:23:27 -0500 | [diff] [blame] | 31 | #include "incore.h" |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 32 | #include "glock.h" |
| 33 | #include "glops.h" |
| 34 | #include "inode.h" |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 35 | #include "lops.h" |
| 36 | #include "meta_io.h" |
| 37 | #include "quota.h" |
| 38 | #include "super.h" |
Steven Whitehouse | 5c676f6 | 2006-02-27 17:23:27 -0500 | [diff] [blame] | 39 | #include "util.h" |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 40 | #include "bmap.h" |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 41 | #define CREATE_TRACE_POINTS |
| 42 | #include "trace_gfs2.h" |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 43 | |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 44 | struct gfs2_gl_hash_bucket { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 45 | struct hlist_head hb_list; |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 46 | }; |
| 47 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 48 | struct gfs2_glock_iter { |
| 49 | int hash; /* hash bucket index */ |
| 50 | struct gfs2_sbd *sdp; /* incore superblock */ |
| 51 | struct gfs2_glock *gl; /* current glock struct */ |
| 52 | char string[512]; /* scratch space */ |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 53 | }; |
| 54 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 55 | typedef void (*glock_examiner) (struct gfs2_glock * gl); |
| 56 | |
Adrian Bunk | 08bc2db | 2006-04-28 10:59:12 -0400 | [diff] [blame] | 57 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 58 | static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl); |
| 59 | #define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { __dump_glock(NULL, gl); BUG(); } } while(0) |
| 60 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 61 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 62 | static struct dentry *gfs2_root; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 63 | static struct workqueue_struct *glock_workqueue; |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 64 | struct workqueue_struct *gfs2_delete_workqueue; |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 65 | static LIST_HEAD(lru_list); |
| 66 | static atomic_t lru_count = ATOMIC_INIT(0); |
Julia Lawall | eb8374e | 2008-12-25 15:35:27 +0100 | [diff] [blame] | 67 | static DEFINE_SPINLOCK(lru_lock); |
Adrian Bunk | 08bc2db | 2006-04-28 10:59:12 -0400 | [diff] [blame] | 68 | |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 69 | #define GFS2_GL_HASH_SHIFT 15 |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 70 | #define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT) |
| 71 | #define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1) |
| 72 | |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 73 | 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] | 74 | static struct dentry *gfs2_root; |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 75 | |
| 76 | /* |
| 77 | * Despite what you might think, the numbers below are not arbitrary :-) |
| 78 | * They are taken from the ipv4 routing hash code, which is well tested |
| 79 | * and thus should be nearly optimal. Later on we might tweek the numbers |
| 80 | * but for now this should be fine. |
| 81 | * |
| 82 | * The reason for putting the locks in a separate array from the list heads |
| 83 | * is that we can have fewer locks than list heads and save memory. We use |
| 84 | * the same hash function for both, but with a different hash mask. |
| 85 | */ |
| 86 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ |
| 87 | defined(CONFIG_PROVE_LOCKING) |
| 88 | |
| 89 | #ifdef CONFIG_LOCKDEP |
| 90 | # define GL_HASH_LOCK_SZ 256 |
| 91 | #else |
| 92 | # if NR_CPUS >= 32 |
| 93 | # define GL_HASH_LOCK_SZ 4096 |
| 94 | # elif NR_CPUS >= 16 |
| 95 | # define GL_HASH_LOCK_SZ 2048 |
| 96 | # elif NR_CPUS >= 8 |
| 97 | # define GL_HASH_LOCK_SZ 1024 |
| 98 | # elif NR_CPUS >= 4 |
| 99 | # define GL_HASH_LOCK_SZ 512 |
| 100 | # else |
| 101 | # define GL_HASH_LOCK_SZ 256 |
| 102 | # endif |
| 103 | #endif |
| 104 | |
| 105 | /* We never want more locks than chains */ |
| 106 | #if GFS2_GL_HASH_SIZE < GL_HASH_LOCK_SZ |
| 107 | # undef GL_HASH_LOCK_SZ |
| 108 | # define GL_HASH_LOCK_SZ GFS2_GL_HASH_SIZE |
| 109 | #endif |
| 110 | |
| 111 | static rwlock_t gl_hash_locks[GL_HASH_LOCK_SZ]; |
| 112 | |
| 113 | static inline rwlock_t *gl_lock_addr(unsigned int x) |
| 114 | { |
Steven Whitehouse | 9461061 | 2006-09-09 18:59:27 -0400 | [diff] [blame] | 115 | return &gl_hash_locks[x & (GL_HASH_LOCK_SZ-1)]; |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 116 | } |
| 117 | #else /* not SMP, so no spinlocks required */ |
Randy Dunlap | 0ac2306 | 2006-11-28 22:29:19 -0800 | [diff] [blame] | 118 | static inline rwlock_t *gl_lock_addr(unsigned int x) |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 119 | { |
| 120 | return NULL; |
| 121 | } |
| 122 | #endif |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 123 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 124 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 125 | * gl_hash() - Turn glock number into hash bucket number |
| 126 | * @lock: The glock number |
| 127 | * |
| 128 | * Returns: The number of the corresponding hash bucket |
| 129 | */ |
| 130 | |
Steven Whitehouse | b854785 | 2006-09-07 13:12:27 -0400 | [diff] [blame] | 131 | static unsigned int gl_hash(const struct gfs2_sbd *sdp, |
| 132 | const struct lm_lockname *name) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 133 | { |
| 134 | unsigned int h; |
| 135 | |
Steven Whitehouse | cd91549 | 2006-09-04 12:49:07 -0400 | [diff] [blame] | 136 | h = jhash(&name->ln_number, sizeof(u64), 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 137 | h = jhash(&name->ln_type, sizeof(unsigned int), h); |
Steven Whitehouse | b854785 | 2006-09-07 13:12:27 -0400 | [diff] [blame] | 138 | h = jhash(&sdp, sizeof(struct gfs2_sbd *), h); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 139 | h &= GFS2_GL_HASH_MASK; |
| 140 | |
| 141 | return h; |
| 142 | } |
| 143 | |
| 144 | /** |
| 145 | * glock_free() - Perform a few checks and then release struct gfs2_glock |
| 146 | * @gl: The glock to release |
| 147 | * |
| 148 | * Also calls lock module to release its internal structure for this glock. |
| 149 | * |
| 150 | */ |
| 151 | |
| 152 | static void glock_free(struct gfs2_glock *gl) |
| 153 | { |
| 154 | struct gfs2_sbd *sdp = gl->gl_sbd; |
Steven Whitehouse | 009d851 | 2009-12-08 12:12:13 +0000 | [diff] [blame] | 155 | struct address_space *mapping = gfs2_glock2aspace(gl); |
| 156 | struct kmem_cache *cachep = gfs2_glock_cachep; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 157 | |
Steven Whitehouse | 009d851 | 2009-12-08 12:12:13 +0000 | [diff] [blame] | 158 | GLOCK_BUG_ON(gl, mapping && mapping->nrpages); |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 159 | trace_gfs2_glock_put(gl); |
Steven Whitehouse | 009d851 | 2009-12-08 12:12:13 +0000 | [diff] [blame] | 160 | if (mapping) |
| 161 | cachep = gfs2_glock_aspace_cachep; |
| 162 | sdp->sd_lockstruct.ls_ops->lm_put_lock(cachep, gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 163 | } |
| 164 | |
| 165 | /** |
| 166 | * gfs2_glock_hold() - increment reference count on glock |
| 167 | * @gl: The glock to hold |
| 168 | * |
| 169 | */ |
| 170 | |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 171 | void gfs2_glock_hold(struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 172 | { |
Steven Whitehouse | d8348de | 2009-02-05 10:12:38 +0000 | [diff] [blame] | 173 | GLOCK_BUG_ON(gl, atomic_read(&gl->gl_ref) == 0); |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 174 | atomic_inc(&gl->gl_ref); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 175 | } |
| 176 | |
| 177 | /** |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 178 | * demote_ok - Check to see if it's ok to unlock a glock |
| 179 | * @gl: the glock |
| 180 | * |
| 181 | * Returns: 1 if it's ok |
| 182 | */ |
| 183 | |
| 184 | static int demote_ok(const struct gfs2_glock *gl) |
| 185 | { |
| 186 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
| 187 | |
| 188 | if (gl->gl_state == LM_ST_UNLOCKED) |
| 189 | return 0; |
| 190 | if (!list_empty(&gl->gl_holders)) |
| 191 | return 0; |
| 192 | if (glops->go_demote_ok) |
| 193 | return glops->go_demote_ok(gl); |
| 194 | return 1; |
| 195 | } |
| 196 | |
| 197 | /** |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 198 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list |
| 199 | * @gl: the glock |
| 200 | * |
| 201 | */ |
| 202 | |
| 203 | static void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) |
| 204 | { |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 205 | int may_reclaim; |
| 206 | may_reclaim = (demote_ok(gl) && |
| 207 | (atomic_read(&gl->gl_ref) == 1 || |
| 208 | (gl->gl_name.ln_type == LM_TYPE_INODE && |
| 209 | atomic_read(&gl->gl_ref) <= 2))); |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 210 | spin_lock(&lru_lock); |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 211 | if (list_empty(&gl->gl_lru) && may_reclaim) { |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 212 | list_add_tail(&gl->gl_lru, &lru_list); |
| 213 | atomic_inc(&lru_count); |
| 214 | } |
| 215 | spin_unlock(&lru_lock); |
| 216 | } |
| 217 | |
| 218 | /** |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 219 | * gfs2_glock_put_nolock() - Decrement reference count on glock |
| 220 | * @gl: The glock to put |
| 221 | * |
| 222 | * This function should only be used if the caller has its own reference |
| 223 | * to the glock, in addition to the one it is dropping. |
| 224 | */ |
| 225 | |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 226 | void gfs2_glock_put_nolock(struct gfs2_glock *gl) |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 227 | { |
| 228 | if (atomic_dec_and_test(&gl->gl_ref)) |
| 229 | GLOCK_BUG_ON(gl, 1); |
| 230 | gfs2_glock_schedule_for_reclaim(gl); |
| 231 | } |
| 232 | |
| 233 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 234 | * gfs2_glock_put() - Decrement reference count on glock |
| 235 | * @gl: The glock to put |
| 236 | * |
| 237 | */ |
| 238 | |
| 239 | int gfs2_glock_put(struct gfs2_glock *gl) |
| 240 | { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 241 | int rv = 0; |
| 242 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 243 | write_lock(gl_lock_addr(gl->gl_hash)); |
Steven Whitehouse | 26bb750 | 2009-11-27 10:31:11 +0000 | [diff] [blame] | 244 | if (atomic_dec_and_lock(&gl->gl_ref, &lru_lock)) { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 245 | hlist_del(&gl->gl_list); |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 246 | if (!list_empty(&gl->gl_lru)) { |
| 247 | list_del_init(&gl->gl_lru); |
| 248 | atomic_dec(&lru_count); |
| 249 | } |
| 250 | spin_unlock(&lru_lock); |
Steven Whitehouse | 26bb750 | 2009-11-27 10:31:11 +0000 | [diff] [blame] | 251 | write_unlock(gl_lock_addr(gl->gl_hash)); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 252 | GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 253 | glock_free(gl); |
| 254 | rv = 1; |
| 255 | goto out; |
| 256 | } |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 257 | spin_lock(&gl->gl_spin); |
| 258 | gfs2_glock_schedule_for_reclaim(gl); |
| 259 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | d8348de | 2009-02-05 10:12:38 +0000 | [diff] [blame] | 260 | write_unlock(gl_lock_addr(gl->gl_hash)); |
Steven Whitehouse | a2242db | 2006-08-24 17:03:05 -0400 | [diff] [blame] | 261 | out: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 262 | return rv; |
| 263 | } |
| 264 | |
| 265 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 266 | * search_bucket() - Find struct gfs2_glock by lock number |
| 267 | * @bucket: the bucket to search |
| 268 | * @name: The lock name |
| 269 | * |
| 270 | * Returns: NULL, or the struct gfs2_glock with the requested number |
| 271 | */ |
| 272 | |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 273 | static struct gfs2_glock *search_bucket(unsigned int hash, |
Steven Whitehouse | 899be4d | 2006-08-30 12:50:28 -0400 | [diff] [blame] | 274 | const struct gfs2_sbd *sdp, |
Steven Whitehouse | d6a5372 | 2006-08-30 11:16:23 -0400 | [diff] [blame] | 275 | const struct lm_lockname *name) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 276 | { |
| 277 | struct gfs2_glock *gl; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 278 | struct hlist_node *h; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 279 | |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 280 | 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] | 281 | if (!lm_name_equal(&gl->gl_name, name)) |
| 282 | continue; |
Steven Whitehouse | 899be4d | 2006-08-30 12:50:28 -0400 | [diff] [blame] | 283 | if (gl->gl_sbd != sdp) |
| 284 | continue; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 285 | |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 286 | atomic_inc(&gl->gl_ref); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 287 | |
| 288 | return gl; |
| 289 | } |
| 290 | |
| 291 | return NULL; |
| 292 | } |
| 293 | |
| 294 | /** |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 295 | * may_grant - check if its ok to grant a new lock |
| 296 | * @gl: The glock |
| 297 | * @gh: The lock request which we wish to grant |
| 298 | * |
| 299 | * Returns: true if its ok to grant the lock |
| 300 | */ |
| 301 | |
| 302 | static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh) |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 303 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 304 | const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list); |
| 305 | if ((gh->gh_state == LM_ST_EXCLUSIVE || |
| 306 | gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head) |
| 307 | return 0; |
| 308 | if (gl->gl_state == gh->gh_state) |
| 309 | return 1; |
| 310 | if (gh->gh_flags & GL_EXACT) |
| 311 | return 0; |
Steven Whitehouse | 209806a | 2008-07-07 10:07:28 +0100 | [diff] [blame] | 312 | if (gl->gl_state == LM_ST_EXCLUSIVE) { |
| 313 | if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED) |
| 314 | return 1; |
| 315 | if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED) |
| 316 | return 1; |
| 317 | } |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 318 | if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY)) |
| 319 | return 1; |
| 320 | return 0; |
| 321 | } |
| 322 | |
| 323 | static void gfs2_holder_wake(struct gfs2_holder *gh) |
| 324 | { |
| 325 | clear_bit(HIF_WAIT, &gh->gh_iflags); |
| 326 | smp_mb__after_clear_bit(); |
| 327 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); |
| 328 | } |
| 329 | |
| 330 | /** |
Steven Whitehouse | d5341a9 | 2010-07-23 14:05:51 +0100 | [diff] [blame] | 331 | * do_error - Something unexpected has happened during a lock request |
| 332 | * |
| 333 | */ |
| 334 | |
| 335 | static inline void do_error(struct gfs2_glock *gl, const int ret) |
| 336 | { |
| 337 | struct gfs2_holder *gh, *tmp; |
| 338 | |
| 339 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { |
| 340 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) |
| 341 | continue; |
| 342 | if (ret & LM_OUT_ERROR) |
| 343 | gh->gh_error = -EIO; |
| 344 | else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) |
| 345 | gh->gh_error = GLR_TRYFAILED; |
| 346 | else |
| 347 | continue; |
| 348 | list_del_init(&gh->gh_list); |
| 349 | trace_gfs2_glock_queue(gh, 0); |
| 350 | gfs2_holder_wake(gh); |
| 351 | } |
| 352 | } |
| 353 | |
| 354 | /** |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 355 | * do_promote - promote as many requests as possible on the current queue |
| 356 | * @gl: The glock |
| 357 | * |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 358 | * Returns: 1 if there is a blocked holder at the head of the list, or 2 |
| 359 | * if a type specific operation is underway. |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 360 | */ |
| 361 | |
| 362 | static int do_promote(struct gfs2_glock *gl) |
Harvey Harrison | 55ba474 | 2008-10-24 11:31:12 -0700 | [diff] [blame] | 363 | __releases(&gl->gl_spin) |
| 364 | __acquires(&gl->gl_spin) |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 365 | { |
| 366 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
| 367 | struct gfs2_holder *gh, *tmp; |
| 368 | int ret; |
| 369 | |
| 370 | restart: |
| 371 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { |
| 372 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) |
| 373 | continue; |
| 374 | if (may_grant(gl, gh)) { |
| 375 | if (gh->gh_list.prev == &gl->gl_holders && |
| 376 | glops->go_lock) { |
| 377 | spin_unlock(&gl->gl_spin); |
| 378 | /* FIXME: eliminate this eventually */ |
| 379 | ret = glops->go_lock(gh); |
| 380 | spin_lock(&gl->gl_spin); |
| 381 | if (ret) { |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 382 | if (ret == 1) |
| 383 | return 2; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 384 | gh->gh_error = ret; |
| 385 | list_del_init(&gh->gh_list); |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 386 | trace_gfs2_glock_queue(gh, 0); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 387 | gfs2_holder_wake(gh); |
| 388 | goto restart; |
| 389 | } |
| 390 | set_bit(HIF_HOLDER, &gh->gh_iflags); |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 391 | trace_gfs2_promote(gh, 1); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 392 | gfs2_holder_wake(gh); |
| 393 | goto restart; |
| 394 | } |
| 395 | set_bit(HIF_HOLDER, &gh->gh_iflags); |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 396 | trace_gfs2_promote(gh, 0); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 397 | gfs2_holder_wake(gh); |
| 398 | continue; |
| 399 | } |
| 400 | if (gh->gh_list.prev == &gl->gl_holders) |
| 401 | return 1; |
Steven Whitehouse | d5341a9 | 2010-07-23 14:05:51 +0100 | [diff] [blame] | 402 | do_error(gl, 0); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 403 | break; |
| 404 | } |
| 405 | return 0; |
| 406 | } |
| 407 | |
| 408 | /** |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 409 | * find_first_waiter - find the first gh that's waiting for the glock |
| 410 | * @gl: the glock |
| 411 | */ |
| 412 | |
| 413 | static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl) |
| 414 | { |
| 415 | struct gfs2_holder *gh; |
| 416 | |
| 417 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { |
| 418 | if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) |
| 419 | return gh; |
| 420 | } |
| 421 | return NULL; |
| 422 | } |
| 423 | |
| 424 | /** |
| 425 | * state_change - record that the glock is now in a different state |
| 426 | * @gl: the glock |
| 427 | * @new_state the new state |
| 428 | * |
| 429 | */ |
| 430 | |
| 431 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) |
| 432 | { |
| 433 | int held1, held2; |
| 434 | |
| 435 | held1 = (gl->gl_state != LM_ST_UNLOCKED); |
| 436 | held2 = (new_state != LM_ST_UNLOCKED); |
| 437 | |
| 438 | if (held1 != held2) { |
| 439 | if (held2) |
| 440 | gfs2_glock_hold(gl); |
| 441 | else |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 442 | gfs2_glock_put_nolock(gl); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 443 | } |
Steven Whitehouse | 7b5e3d5 | 2010-09-03 09:39:20 +0100 | [diff] [blame] | 444 | if (held1 && held2 && list_empty(&gl->gl_holders)) |
| 445 | clear_bit(GLF_QUEUED, &gl->gl_flags); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 446 | |
| 447 | gl->gl_state = new_state; |
| 448 | gl->gl_tchange = jiffies; |
| 449 | } |
| 450 | |
| 451 | static void gfs2_demote_wake(struct gfs2_glock *gl) |
| 452 | { |
| 453 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
| 454 | clear_bit(GLF_DEMOTE, &gl->gl_flags); |
| 455 | smp_mb__after_clear_bit(); |
| 456 | wake_up_bit(&gl->gl_flags, GLF_DEMOTE); |
| 457 | } |
| 458 | |
| 459 | /** |
| 460 | * finish_xmote - The DLM has replied to one of our lock requests |
| 461 | * @gl: The glock |
| 462 | * @ret: The status from the DLM |
| 463 | * |
| 464 | */ |
| 465 | |
| 466 | static void finish_xmote(struct gfs2_glock *gl, unsigned int ret) |
| 467 | { |
| 468 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
| 469 | struct gfs2_holder *gh; |
| 470 | unsigned state = ret & LM_OUT_ST_MASK; |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 471 | int rv; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 472 | |
| 473 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 474 | trace_gfs2_glock_state_change(gl, state); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 475 | state_change(gl, state); |
| 476 | gh = find_first_waiter(gl); |
| 477 | |
| 478 | /* Demote to UN request arrived during demote to SH or DF */ |
| 479 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && |
| 480 | state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED) |
| 481 | gl->gl_target = LM_ST_UNLOCKED; |
| 482 | |
| 483 | /* Check for state != intended state */ |
| 484 | if (unlikely(state != gl->gl_target)) { |
| 485 | if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) { |
| 486 | /* move to back of queue and try next entry */ |
| 487 | if (ret & LM_OUT_CANCELED) { |
| 488 | if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0) |
| 489 | list_move_tail(&gh->gh_list, &gl->gl_holders); |
| 490 | gh = find_first_waiter(gl); |
| 491 | gl->gl_target = gh->gh_state; |
| 492 | goto retry; |
| 493 | } |
| 494 | /* Some error or failed "try lock" - report it */ |
| 495 | if ((ret & LM_OUT_ERROR) || |
| 496 | (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { |
| 497 | gl->gl_target = gl->gl_state; |
| 498 | do_error(gl, ret); |
| 499 | goto out; |
| 500 | } |
| 501 | } |
| 502 | switch(state) { |
| 503 | /* Unlocked due to conversion deadlock, try again */ |
| 504 | case LM_ST_UNLOCKED: |
| 505 | retry: |
| 506 | do_xmote(gl, gh, gl->gl_target); |
| 507 | break; |
| 508 | /* Conversion fails, unlock and try again */ |
| 509 | case LM_ST_SHARED: |
| 510 | case LM_ST_DEFERRED: |
| 511 | do_xmote(gl, gh, LM_ST_UNLOCKED); |
| 512 | break; |
| 513 | default: /* Everything else */ |
| 514 | printk(KERN_ERR "GFS2: wanted %u got %u\n", gl->gl_target, state); |
| 515 | GLOCK_BUG_ON(gl, 1); |
| 516 | } |
| 517 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 518 | return; |
| 519 | } |
| 520 | |
| 521 | /* Fast path - we got what we asked for */ |
| 522 | if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) |
| 523 | gfs2_demote_wake(gl); |
| 524 | if (state != LM_ST_UNLOCKED) { |
| 525 | if (glops->go_xmote_bh) { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 526 | spin_unlock(&gl->gl_spin); |
| 527 | rv = glops->go_xmote_bh(gl, gh); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 528 | spin_lock(&gl->gl_spin); |
| 529 | if (rv) { |
| 530 | do_error(gl, rv); |
| 531 | goto out; |
| 532 | } |
| 533 | } |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 534 | rv = do_promote(gl); |
| 535 | if (rv == 2) |
| 536 | goto out_locked; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 537 | } |
| 538 | out: |
| 539 | clear_bit(GLF_LOCK, &gl->gl_flags); |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 540 | out_locked: |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 541 | spin_unlock(&gl->gl_spin); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 542 | } |
| 543 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 544 | static unsigned int gfs2_lm_lock(struct gfs2_sbd *sdp, void *lock, |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 545 | unsigned int req_state, |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 546 | unsigned int flags) |
| 547 | { |
| 548 | int ret = LM_OUT_ERROR; |
Steven Whitehouse | 048bca2 | 2008-05-23 14:46:04 +0100 | [diff] [blame] | 549 | |
| 550 | if (!sdp->sd_lockstruct.ls_ops->lm_lock) |
| 551 | return req_state == LM_ST_UNLOCKED ? 0 : req_state; |
| 552 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 553 | if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 554 | ret = sdp->sd_lockstruct.ls_ops->lm_lock(lock, |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 555 | req_state, flags); |
| 556 | return ret; |
| 557 | } |
| 558 | |
| 559 | /** |
| 560 | * do_xmote - Calls the DLM to change the state of a lock |
| 561 | * @gl: The lock state |
| 562 | * @gh: The holder (only for promotes) |
| 563 | * @target: The target lock state |
| 564 | * |
| 565 | */ |
| 566 | |
| 567 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target) |
Harvey Harrison | 55ba474 | 2008-10-24 11:31:12 -0700 | [diff] [blame] | 568 | __releases(&gl->gl_spin) |
| 569 | __acquires(&gl->gl_spin) |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 570 | { |
| 571 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
| 572 | struct gfs2_sbd *sdp = gl->gl_sbd; |
| 573 | unsigned int lck_flags = gh ? gh->gh_flags : 0; |
| 574 | int ret; |
| 575 | |
| 576 | lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | |
| 577 | LM_FLAG_PRIORITY); |
| 578 | BUG_ON(gl->gl_state == target); |
| 579 | BUG_ON(gl->gl_state == gl->gl_target); |
| 580 | if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) && |
| 581 | glops->go_inval) { |
| 582 | set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); |
| 583 | do_error(gl, 0); /* Fail queued try locks */ |
| 584 | } |
| 585 | spin_unlock(&gl->gl_spin); |
| 586 | if (glops->go_xmote_th) |
| 587 | glops->go_xmote_th(gl); |
| 588 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
| 589 | glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA); |
| 590 | clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); |
| 591 | |
| 592 | gfs2_glock_hold(gl); |
| 593 | if (target != LM_ST_UNLOCKED && (gl->gl_state == LM_ST_SHARED || |
| 594 | gl->gl_state == LM_ST_DEFERRED) && |
| 595 | !(lck_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) |
| 596 | lck_flags |= LM_FLAG_TRY_1CB; |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 597 | ret = gfs2_lm_lock(sdp, gl, target, lck_flags); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 598 | |
| 599 | if (!(ret & LM_OUT_ASYNC)) { |
| 600 | finish_xmote(gl, ret); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 601 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
| 602 | gfs2_glock_put(gl); |
| 603 | } else { |
| 604 | GLOCK_BUG_ON(gl, ret != LM_OUT_ASYNC); |
| 605 | } |
| 606 | spin_lock(&gl->gl_spin); |
| 607 | } |
| 608 | |
| 609 | /** |
| 610 | * find_first_holder - find the first "holder" gh |
| 611 | * @gl: the glock |
| 612 | */ |
| 613 | |
| 614 | static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl) |
| 615 | { |
| 616 | struct gfs2_holder *gh; |
| 617 | |
| 618 | if (!list_empty(&gl->gl_holders)) { |
| 619 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); |
| 620 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) |
| 621 | return gh; |
| 622 | } |
| 623 | return NULL; |
| 624 | } |
| 625 | |
| 626 | /** |
| 627 | * run_queue - do all outstanding tasks related to a glock |
| 628 | * @gl: The glock in question |
| 629 | * @nonblock: True if we must not block in run_queue |
| 630 | * |
| 631 | */ |
| 632 | |
| 633 | static void run_queue(struct gfs2_glock *gl, const int nonblock) |
Harvey Harrison | 55ba474 | 2008-10-24 11:31:12 -0700 | [diff] [blame] | 634 | __releases(&gl->gl_spin) |
| 635 | __acquires(&gl->gl_spin) |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 636 | { |
| 637 | struct gfs2_holder *gh = NULL; |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 638 | int ret; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 639 | |
| 640 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) |
| 641 | return; |
| 642 | |
| 643 | GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)); |
| 644 | |
| 645 | if (test_bit(GLF_DEMOTE, &gl->gl_flags) && |
| 646 | gl->gl_demote_state != gl->gl_state) { |
| 647 | if (find_first_holder(gl)) |
Steven Whitehouse | d8348de | 2009-02-05 10:12:38 +0000 | [diff] [blame] | 648 | goto out_unlock; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 649 | if (nonblock) |
| 650 | goto out_sched; |
| 651 | set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); |
Steven Whitehouse | 265d529c | 2008-07-07 10:02:36 +0100 | [diff] [blame] | 652 | GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 653 | gl->gl_target = gl->gl_demote_state; |
| 654 | } else { |
| 655 | if (test_bit(GLF_DEMOTE, &gl->gl_flags)) |
| 656 | gfs2_demote_wake(gl); |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 657 | ret = do_promote(gl); |
| 658 | if (ret == 0) |
Steven Whitehouse | d8348de | 2009-02-05 10:12:38 +0000 | [diff] [blame] | 659 | goto out_unlock; |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 660 | if (ret == 2) |
Steven Whitehouse | a228df6 | 2009-04-07 14:01:34 +0100 | [diff] [blame] | 661 | goto out; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 662 | gh = find_first_waiter(gl); |
| 663 | gl->gl_target = gh->gh_state; |
| 664 | if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) |
| 665 | do_error(gl, 0); /* Fail queued try locks */ |
| 666 | } |
| 667 | do_xmote(gl, gh, gl->gl_target); |
Steven Whitehouse | a228df6 | 2009-04-07 14:01:34 +0100 | [diff] [blame] | 668 | out: |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 669 | return; |
| 670 | |
| 671 | out_sched: |
Steven Whitehouse | 7e71c55 | 2009-09-22 10:56:16 +0100 | [diff] [blame] | 672 | clear_bit(GLF_LOCK, &gl->gl_flags); |
| 673 | smp_mb__after_clear_bit(); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 674 | gfs2_glock_hold(gl); |
| 675 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
Benjamin Marzinski | 8ff22a6 | 2009-07-10 18:04:24 -0500 | [diff] [blame] | 676 | gfs2_glock_put_nolock(gl); |
Steven Whitehouse | 7e71c55 | 2009-09-22 10:56:16 +0100 | [diff] [blame] | 677 | return; |
| 678 | |
Steven Whitehouse | d8348de | 2009-02-05 10:12:38 +0000 | [diff] [blame] | 679 | out_unlock: |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 680 | clear_bit(GLF_LOCK, &gl->gl_flags); |
Steven Whitehouse | 7e71c55 | 2009-09-22 10:56:16 +0100 | [diff] [blame] | 681 | smp_mb__after_clear_bit(); |
| 682 | return; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 683 | } |
| 684 | |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 685 | static void delete_work_func(struct work_struct *work) |
| 686 | { |
| 687 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete); |
| 688 | struct gfs2_sbd *sdp = gl->gl_sbd; |
Steven Whitehouse | 044b941 | 2010-11-03 20:01:07 +0000 | [diff] [blame] | 689 | struct gfs2_inode *ip; |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 690 | struct inode *inode; |
Steven Whitehouse | 044b941 | 2010-11-03 20:01:07 +0000 | [diff] [blame] | 691 | u64 no_addr = gl->gl_name.ln_number; |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 692 | |
Steven Whitehouse | 044b941 | 2010-11-03 20:01:07 +0000 | [diff] [blame] | 693 | ip = gl->gl_object; |
| 694 | /* Note: Unsafe to dereference ip as we don't hold right refs/locks */ |
| 695 | |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 696 | if (ip) |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 697 | inode = gfs2_ilookup(sdp->sd_vfs, no_addr); |
Steven Whitehouse | 044b941 | 2010-11-03 20:01:07 +0000 | [diff] [blame] | 698 | else |
| 699 | inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED); |
| 700 | if (inode && !IS_ERR(inode)) { |
| 701 | d_prune_aliases(inode); |
| 702 | iput(inode); |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 703 | } |
| 704 | gfs2_glock_put(gl); |
| 705 | } |
| 706 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 707 | static void glock_work_func(struct work_struct *work) |
| 708 | { |
| 709 | unsigned long delay = 0; |
| 710 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work); |
Steven Whitehouse | 26bb750 | 2009-11-27 10:31:11 +0000 | [diff] [blame] | 711 | int drop_ref = 0; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 712 | |
Steven Whitehouse | 26bb750 | 2009-11-27 10:31:11 +0000 | [diff] [blame] | 713 | if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 714 | finish_xmote(gl, gl->gl_reply); |
Steven Whitehouse | 26bb750 | 2009-11-27 10:31:11 +0000 | [diff] [blame] | 715 | drop_ref = 1; |
| 716 | } |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 717 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | 265d529c | 2008-07-07 10:02:36 +0100 | [diff] [blame] | 718 | if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
| 719 | gl->gl_state != LM_ST_UNLOCKED && |
| 720 | gl->gl_demote_state != LM_ST_EXCLUSIVE) { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 721 | unsigned long holdtime, now = jiffies; |
| 722 | holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time; |
| 723 | if (time_before(now, holdtime)) |
| 724 | delay = holdtime - now; |
| 725 | set_bit(delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE, &gl->gl_flags); |
| 726 | } |
| 727 | run_queue(gl, 0); |
| 728 | spin_unlock(&gl->gl_spin); |
| 729 | if (!delay || |
| 730 | queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
| 731 | gfs2_glock_put(gl); |
Steven Whitehouse | 26bb750 | 2009-11-27 10:31:11 +0000 | [diff] [blame] | 732 | if (drop_ref) |
| 733 | gfs2_glock_put(gl); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 734 | } |
| 735 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 736 | /** |
| 737 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist |
| 738 | * @sdp: The GFS2 superblock |
| 739 | * @number: the lock number |
| 740 | * @glops: The glock_operations to use |
| 741 | * @create: If 0, don't create the glock if it doesn't exist |
| 742 | * @glp: the glock is returned here |
| 743 | * |
| 744 | * This does not lock a glock, just finds/creates structures for one. |
| 745 | * |
| 746 | * Returns: errno |
| 747 | */ |
| 748 | |
Steven Whitehouse | cd91549 | 2006-09-04 12:49:07 -0400 | [diff] [blame] | 749 | int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 750 | const struct gfs2_glock_operations *glops, int create, |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 751 | struct gfs2_glock **glp) |
| 752 | { |
Steven Whitehouse | 009d851 | 2009-12-08 12:12:13 +0000 | [diff] [blame] | 753 | struct super_block *s = sdp->sd_vfs; |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 754 | struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type }; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 755 | struct gfs2_glock *gl, *tmp; |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 756 | unsigned int hash = gl_hash(sdp, &name); |
Steven Whitehouse | 009d851 | 2009-12-08 12:12:13 +0000 | [diff] [blame] | 757 | struct address_space *mapping; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 758 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 759 | read_lock(gl_lock_addr(hash)); |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 760 | gl = search_bucket(hash, sdp, &name); |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 761 | read_unlock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 762 | |
Steven Whitehouse | 64d576b | 2009-02-12 13:31:58 +0000 | [diff] [blame] | 763 | *glp = gl; |
| 764 | if (gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 765 | return 0; |
Steven Whitehouse | 64d576b | 2009-02-12 13:31:58 +0000 | [diff] [blame] | 766 | if (!create) |
| 767 | return -ENOENT; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 768 | |
Steven Whitehouse | 009d851 | 2009-12-08 12:12:13 +0000 | [diff] [blame] | 769 | if (glops->go_flags & GLOF_ASPACE) |
| 770 | gl = kmem_cache_alloc(gfs2_glock_aspace_cachep, GFP_KERNEL); |
| 771 | else |
| 772 | gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 773 | if (!gl) |
| 774 | return -ENOMEM; |
| 775 | |
Steven Whitehouse | 8f05228 | 2010-01-29 15:21:27 +0000 | [diff] [blame] | 776 | atomic_inc(&sdp->sd_glock_disposal); |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 777 | gl->gl_flags = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 778 | gl->gl_name = name; |
Steven Whitehouse | 16feb9f | 2006-09-13 10:43:37 -0400 | [diff] [blame] | 779 | atomic_set(&gl->gl_ref, 1); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 780 | gl->gl_state = LM_ST_UNLOCKED; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 781 | gl->gl_target = LM_ST_UNLOCKED; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 782 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 783 | gl->gl_hash = hash; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 784 | gl->gl_ops = glops; |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 785 | snprintf(gl->gl_strname, GDLM_STRNAME_BYTES, "%8x%16llx", name.ln_type, (unsigned long long)number); |
| 786 | memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb)); |
| 787 | gl->gl_lksb.sb_lvbptr = gl->gl_lvb; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 788 | gl->gl_tchange = jiffies; |
Steven Whitehouse | ec45d9f | 2006-08-30 10:36:52 -0400 | [diff] [blame] | 789 | gl->gl_object = NULL; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 790 | gl->gl_sbd = sdp; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 791 | INIT_DELAYED_WORK(&gl->gl_work, glock_work_func); |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 792 | INIT_WORK(&gl->gl_delete, delete_work_func); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 793 | |
Steven Whitehouse | 009d851 | 2009-12-08 12:12:13 +0000 | [diff] [blame] | 794 | mapping = gfs2_glock2aspace(gl); |
| 795 | if (mapping) { |
| 796 | mapping->a_ops = &gfs2_meta_aops; |
| 797 | mapping->host = s->s_bdev->bd_inode; |
| 798 | mapping->flags = 0; |
| 799 | mapping_set_gfp_mask(mapping, GFP_NOFS); |
| 800 | mapping->assoc_mapping = NULL; |
| 801 | mapping->backing_dev_info = s->s_bdi; |
| 802 | mapping->writeback_index = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 803 | } |
| 804 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 805 | write_lock(gl_lock_addr(hash)); |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 806 | tmp = search_bucket(hash, sdp, &name); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 807 | if (tmp) { |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 808 | write_unlock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 809 | glock_free(gl); |
| 810 | gl = tmp; |
| 811 | } else { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 812 | hlist_add_head(&gl->gl_list, &gl_hash_table[hash].hb_list); |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 813 | write_unlock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 814 | } |
| 815 | |
| 816 | *glp = gl; |
| 817 | |
| 818 | return 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 819 | } |
| 820 | |
| 821 | /** |
| 822 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way |
| 823 | * @gl: the glock |
| 824 | * @state: the state we're requesting |
| 825 | * @flags: the modifier flags |
| 826 | * @gh: the holder structure |
| 827 | * |
| 828 | */ |
| 829 | |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 830 | 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] | 831 | struct gfs2_holder *gh) |
| 832 | { |
| 833 | INIT_LIST_HEAD(&gh->gh_list); |
| 834 | gh->gh_gl = gl; |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 835 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
Pavel Emelyanov | b1e058d | 2008-02-07 00:13:19 -0800 | [diff] [blame] | 836 | gh->gh_owner_pid = get_pid(task_pid(current)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 837 | gh->gh_state = state; |
| 838 | gh->gh_flags = flags; |
| 839 | gh->gh_error = 0; |
| 840 | gh->gh_iflags = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 841 | gfs2_glock_hold(gl); |
| 842 | } |
| 843 | |
| 844 | /** |
| 845 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it |
| 846 | * @state: the state we're requesting |
| 847 | * @flags: the modifier flags |
| 848 | * @gh: the holder structure |
| 849 | * |
| 850 | * Don't mess with the glock. |
| 851 | * |
| 852 | */ |
| 853 | |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 854 | 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] | 855 | { |
| 856 | gh->gh_state = state; |
Steven Whitehouse | 579b78a | 2006-04-26 14:58:26 -0400 | [diff] [blame] | 857 | gh->gh_flags = flags; |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 858 | gh->gh_iflags = 0; |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 859 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
Bob Peterson | 1a0eae8 | 2010-04-14 11:58:16 -0400 | [diff] [blame] | 860 | if (gh->gh_owner_pid) |
| 861 | put_pid(gh->gh_owner_pid); |
| 862 | gh->gh_owner_pid = get_pid(task_pid(current)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 863 | } |
| 864 | |
| 865 | /** |
| 866 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) |
| 867 | * @gh: the holder structure |
| 868 | * |
| 869 | */ |
| 870 | |
| 871 | void gfs2_holder_uninit(struct gfs2_holder *gh) |
| 872 | { |
Pavel Emelyanov | b1e058d | 2008-02-07 00:13:19 -0800 | [diff] [blame] | 873 | put_pid(gh->gh_owner_pid); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 874 | gfs2_glock_put(gh->gh_gl); |
| 875 | gh->gh_gl = NULL; |
Steven Whitehouse | d0dc80d | 2006-03-29 14:36:49 -0500 | [diff] [blame] | 876 | gh->gh_ip = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 877 | } |
| 878 | |
Steven Whitehouse | fe64d51 | 2009-05-19 10:01:18 +0100 | [diff] [blame] | 879 | /** |
| 880 | * gfs2_glock_holder_wait |
| 881 | * @word: unused |
| 882 | * |
| 883 | * This function and gfs2_glock_demote_wait both show up in the WCHAN |
| 884 | * field. Thus I've separated these otherwise identical functions in |
| 885 | * order to be more informative to the user. |
| 886 | */ |
| 887 | |
| 888 | static int gfs2_glock_holder_wait(void *word) |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 889 | { |
| 890 | schedule(); |
| 891 | return 0; |
| 892 | } |
| 893 | |
Steven Whitehouse | fe64d51 | 2009-05-19 10:01:18 +0100 | [diff] [blame] | 894 | static int gfs2_glock_demote_wait(void *word) |
| 895 | { |
| 896 | schedule(); |
| 897 | return 0; |
| 898 | } |
| 899 | |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 900 | static void wait_on_holder(struct gfs2_holder *gh) |
| 901 | { |
| 902 | might_sleep(); |
Steven Whitehouse | fe64d51 | 2009-05-19 10:01:18 +0100 | [diff] [blame] | 903 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, gfs2_glock_holder_wait, TASK_UNINTERRUPTIBLE); |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 904 | } |
| 905 | |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 906 | static void wait_on_demote(struct gfs2_glock *gl) |
| 907 | { |
| 908 | might_sleep(); |
Steven Whitehouse | fe64d51 | 2009-05-19 10:01:18 +0100 | [diff] [blame] | 909 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 910 | } |
| 911 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 912 | /** |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 913 | * handle_callback - process a demote request |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 914 | * @gl: the glock |
| 915 | * @state: the state the caller wants us to change to |
| 916 | * |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 917 | * There are only two requests that we are going to see in actual |
| 918 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 919 | */ |
| 920 | |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 921 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 922 | unsigned long delay) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 923 | { |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 924 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
| 925 | |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 926 | set_bit(bit, &gl->gl_flags); |
| 927 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { |
Steven Whitehouse | 3b8249f | 2007-03-16 09:40:31 +0000 | [diff] [blame] | 928 | gl->gl_demote_state = state; |
| 929 | gl->gl_demote_time = jiffies; |
Josef Whiter | 26caee5 | 2007-07-23 10:02:40 +0100 | [diff] [blame] | 930 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
| 931 | gl->gl_demote_state != state) { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 932 | gl->gl_demote_state = LM_ST_UNLOCKED; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 933 | } |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 934 | if (gl->gl_ops->go_callback) |
| 935 | gl->gl_ops->go_callback(gl); |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 936 | trace_gfs2_demote_rq(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 937 | } |
| 938 | |
| 939 | /** |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 940 | * gfs2_glock_wait - wait on a glock acquisition |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 941 | * @gh: the glock holder |
| 942 | * |
| 943 | * Returns: 0 on success |
| 944 | */ |
| 945 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 946 | int gfs2_glock_wait(struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 947 | { |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 948 | wait_on_holder(gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 949 | return gh->gh_error; |
| 950 | } |
| 951 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 952 | void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 953 | { |
Joe Perches | 5e69069 | 2010-11-09 16:35:20 -0800 | [diff] [blame^] | 954 | struct va_format vaf; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 955 | va_list args; |
| 956 | |
| 957 | va_start(args, fmt); |
Joe Perches | 5e69069 | 2010-11-09 16:35:20 -0800 | [diff] [blame^] | 958 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 959 | if (seq) { |
| 960 | struct gfs2_glock_iter *gi = seq->private; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 961 | vsprintf(gi->string, fmt, args); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 962 | seq_printf(seq, gi->string); |
| 963 | } else { |
Joe Perches | 5e69069 | 2010-11-09 16:35:20 -0800 | [diff] [blame^] | 964 | vaf.fmt = fmt; |
| 965 | vaf.va = &args; |
| 966 | |
| 967 | printk(KERN_ERR " %pV", &vaf); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 968 | } |
Joe Perches | 5e69069 | 2010-11-09 16:35:20 -0800 | [diff] [blame^] | 969 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 970 | va_end(args); |
| 971 | } |
| 972 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 973 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 974 | * add_to_queue - Add a holder to the wait queue (but look for recursion) |
| 975 | * @gh: the holder structure to add |
| 976 | * |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 977 | * Eventually we should move the recursive locking trap to a |
| 978 | * debugging option or something like that. This is the fast |
| 979 | * path and needs to have the minimum number of distractions. |
| 980 | * |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 981 | */ |
| 982 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 983 | static inline void add_to_queue(struct gfs2_holder *gh) |
Harvey Harrison | 55ba474 | 2008-10-24 11:31:12 -0700 | [diff] [blame] | 984 | __releases(&gl->gl_spin) |
| 985 | __acquires(&gl->gl_spin) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 986 | { |
| 987 | struct gfs2_glock *gl = gh->gh_gl; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 988 | struct gfs2_sbd *sdp = gl->gl_sbd; |
| 989 | struct list_head *insert_pt = NULL; |
| 990 | struct gfs2_holder *gh2; |
| 991 | int try_lock = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 992 | |
Pavel Emelyanov | b1e058d | 2008-02-07 00:13:19 -0800 | [diff] [blame] | 993 | BUG_ON(gh->gh_owner_pid == NULL); |
Steven Whitehouse | fee852e | 2007-01-17 15:33:23 +0000 | [diff] [blame] | 994 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
| 995 | BUG(); |
Steven Whitehouse | 190562b | 2006-04-20 16:57:23 -0400 | [diff] [blame] | 996 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 997 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
| 998 | if (test_bit(GLF_LOCK, &gl->gl_flags)) |
| 999 | try_lock = 1; |
| 1000 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
| 1001 | goto fail; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1002 | } |
| 1003 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1004 | list_for_each_entry(gh2, &gl->gl_holders, gh_list) { |
| 1005 | if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && |
| 1006 | (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK))) |
| 1007 | goto trap_recursive; |
| 1008 | if (try_lock && |
| 1009 | !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) && |
| 1010 | !may_grant(gl, gh)) { |
| 1011 | fail: |
| 1012 | gh->gh_error = GLR_TRYFAILED; |
| 1013 | gfs2_holder_wake(gh); |
| 1014 | return; |
| 1015 | } |
| 1016 | if (test_bit(HIF_HOLDER, &gh2->gh_iflags)) |
| 1017 | continue; |
| 1018 | if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt)) |
| 1019 | insert_pt = &gh2->gh_list; |
| 1020 | } |
Steven Whitehouse | 7b5e3d5 | 2010-09-03 09:39:20 +0100 | [diff] [blame] | 1021 | set_bit(GLF_QUEUED, &gl->gl_flags); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1022 | if (likely(insert_pt == NULL)) { |
| 1023 | list_add_tail(&gh->gh_list, &gl->gl_holders); |
| 1024 | if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY)) |
| 1025 | goto do_cancel; |
| 1026 | return; |
| 1027 | } |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 1028 | trace_gfs2_glock_queue(gh, 1); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1029 | list_add_tail(&gh->gh_list, insert_pt); |
| 1030 | do_cancel: |
| 1031 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); |
| 1032 | if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { |
| 1033 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 048bca2 | 2008-05-23 14:46:04 +0100 | [diff] [blame] | 1034 | if (sdp->sd_lockstruct.ls_ops->lm_cancel) |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1035 | sdp->sd_lockstruct.ls_ops->lm_cancel(gl); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1036 | spin_lock(&gl->gl_spin); |
| 1037 | } |
| 1038 | return; |
| 1039 | |
| 1040 | trap_recursive: |
| 1041 | print_symbol(KERN_ERR "original: %s\n", gh2->gh_ip); |
| 1042 | printk(KERN_ERR "pid: %d\n", pid_nr(gh2->gh_owner_pid)); |
| 1043 | printk(KERN_ERR "lock type: %d req lock state : %d\n", |
| 1044 | gh2->gh_gl->gl_name.ln_type, gh2->gh_state); |
| 1045 | print_symbol(KERN_ERR "new: %s\n", gh->gh_ip); |
| 1046 | printk(KERN_ERR "pid: %d\n", pid_nr(gh->gh_owner_pid)); |
| 1047 | printk(KERN_ERR "lock type: %d req lock state : %d\n", |
| 1048 | gh->gh_gl->gl_name.ln_type, gh->gh_state); |
| 1049 | __dump_glock(NULL, gl); |
| 1050 | BUG(); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1051 | } |
| 1052 | |
| 1053 | /** |
| 1054 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) |
| 1055 | * @gh: the holder structure |
| 1056 | * |
| 1057 | * if (gh->gh_flags & GL_ASYNC), this never returns an error |
| 1058 | * |
| 1059 | * Returns: 0, GLR_TRYFAILED, or errno on failure |
| 1060 | */ |
| 1061 | |
| 1062 | int gfs2_glock_nq(struct gfs2_holder *gh) |
| 1063 | { |
| 1064 | struct gfs2_glock *gl = gh->gh_gl; |
| 1065 | struct gfs2_sbd *sdp = gl->gl_sbd; |
| 1066 | int error = 0; |
| 1067 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1068 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1069 | return -EIO; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1070 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1071 | spin_lock(&gl->gl_spin); |
| 1072 | add_to_queue(gh); |
Steven Whitehouse | 0809f6e | 2010-08-02 10:15:17 +0100 | [diff] [blame] | 1073 | if ((LM_FLAG_NOEXP & gh->gh_flags) && |
| 1074 | test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) |
| 1075 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1076 | run_queue(gl, 1); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1077 | spin_unlock(&gl->gl_spin); |
| 1078 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1079 | if (!(gh->gh_flags & GL_ASYNC)) |
| 1080 | error = gfs2_glock_wait(gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1081 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1082 | return error; |
| 1083 | } |
| 1084 | |
| 1085 | /** |
| 1086 | * gfs2_glock_poll - poll to see if an async request has been completed |
| 1087 | * @gh: the holder |
| 1088 | * |
| 1089 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on |
| 1090 | */ |
| 1091 | |
| 1092 | int gfs2_glock_poll(struct gfs2_holder *gh) |
| 1093 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1094 | return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1095 | } |
| 1096 | |
| 1097 | /** |
| 1098 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) |
| 1099 | * @gh: the glock holder |
| 1100 | * |
| 1101 | */ |
| 1102 | |
| 1103 | void gfs2_glock_dq(struct gfs2_holder *gh) |
| 1104 | { |
| 1105 | struct gfs2_glock *gl = gh->gh_gl; |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 1106 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1107 | unsigned delay = 0; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1108 | int fast_path = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1109 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1110 | spin_lock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1111 | if (gh->gh_flags & GL_NOCACHE) |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1112 | handle_callback(gl, LM_ST_UNLOCKED, 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1113 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1114 | list_del_init(&gh->gh_list); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1115 | if (find_first_holder(gl) == NULL) { |
Steven Whitehouse | 3042a2c | 2007-11-02 08:39:34 +0000 | [diff] [blame] | 1116 | if (glops->go_unlock) { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1117 | GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags)); |
Steven Whitehouse | 3042a2c | 2007-11-02 08:39:34 +0000 | [diff] [blame] | 1118 | spin_unlock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1119 | glops->go_unlock(gh); |
Steven Whitehouse | 3042a2c | 2007-11-02 08:39:34 +0000 | [diff] [blame] | 1120 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1121 | clear_bit(GLF_LOCK, &gl->gl_flags); |
Steven Whitehouse | 3042a2c | 2007-11-02 08:39:34 +0000 | [diff] [blame] | 1122 | } |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1123 | if (list_empty(&gl->gl_holders) && |
| 1124 | !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
| 1125 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) |
| 1126 | fast_path = 1; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1127 | } |
Steven Whitehouse | 6399777 | 2009-06-12 08:49:20 +0100 | [diff] [blame] | 1128 | trace_gfs2_glock_queue(gh, 0); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1129 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1130 | if (likely(fast_path)) |
| 1131 | return; |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1132 | |
| 1133 | gfs2_glock_hold(gl); |
| 1134 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
| 1135 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) |
| 1136 | delay = gl->gl_ops->go_min_hold_time; |
| 1137 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
| 1138 | gfs2_glock_put(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1139 | } |
| 1140 | |
Abhijith Das | d93cfa9 | 2007-06-11 08:22:32 +0100 | [diff] [blame] | 1141 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
| 1142 | { |
| 1143 | struct gfs2_glock *gl = gh->gh_gl; |
| 1144 | gfs2_glock_dq(gh); |
| 1145 | wait_on_demote(gl); |
| 1146 | } |
| 1147 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1148 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1149 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it |
| 1150 | * @gh: the holder structure |
| 1151 | * |
| 1152 | */ |
| 1153 | |
| 1154 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) |
| 1155 | { |
| 1156 | gfs2_glock_dq(gh); |
| 1157 | gfs2_holder_uninit(gh); |
| 1158 | } |
| 1159 | |
| 1160 | /** |
| 1161 | * gfs2_glock_nq_num - acquire a glock based on lock number |
| 1162 | * @sdp: the filesystem |
| 1163 | * @number: the lock number |
| 1164 | * @glops: the glock operations for the type of glock |
| 1165 | * @state: the state to acquire the glock in |
| 1166 | * @flags: modifier flags for the aquisition |
| 1167 | * @gh: the struct gfs2_holder |
| 1168 | * |
| 1169 | * Returns: errno |
| 1170 | */ |
| 1171 | |
Steven Whitehouse | cd91549 | 2006-09-04 12:49:07 -0400 | [diff] [blame] | 1172 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
Steven Whitehouse | 8fb4b53 | 2006-08-30 09:30:00 -0400 | [diff] [blame] | 1173 | const struct gfs2_glock_operations *glops, |
| 1174 | unsigned int state, int flags, struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1175 | { |
| 1176 | struct gfs2_glock *gl; |
| 1177 | int error; |
| 1178 | |
| 1179 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); |
| 1180 | if (!error) { |
| 1181 | error = gfs2_glock_nq_init(gl, state, flags, gh); |
| 1182 | gfs2_glock_put(gl); |
| 1183 | } |
| 1184 | |
| 1185 | return error; |
| 1186 | } |
| 1187 | |
| 1188 | /** |
| 1189 | * glock_compare - Compare two struct gfs2_glock structures for sorting |
| 1190 | * @arg_a: the first structure |
| 1191 | * @arg_b: the second structure |
| 1192 | * |
| 1193 | */ |
| 1194 | |
| 1195 | static int glock_compare(const void *arg_a, const void *arg_b) |
| 1196 | { |
Steven Whitehouse | a5e08a9 | 2006-09-09 17:07:05 -0400 | [diff] [blame] | 1197 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
| 1198 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; |
| 1199 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; |
| 1200 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1201 | |
| 1202 | if (a->ln_number > b->ln_number) |
Steven Whitehouse | a5e08a9 | 2006-09-09 17:07:05 -0400 | [diff] [blame] | 1203 | return 1; |
| 1204 | if (a->ln_number < b->ln_number) |
| 1205 | return -1; |
Steven Whitehouse | 1c0f487 | 2007-01-22 12:10:39 -0500 | [diff] [blame] | 1206 | 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] | 1207 | return 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1208 | } |
| 1209 | |
| 1210 | /** |
| 1211 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order |
| 1212 | * @num_gh: the number of structures |
| 1213 | * @ghs: an array of struct gfs2_holder structures |
| 1214 | * |
| 1215 | * Returns: 0 on success (all glocks acquired), |
| 1216 | * errno on failure (no glocks acquired) |
| 1217 | */ |
| 1218 | |
| 1219 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, |
| 1220 | struct gfs2_holder **p) |
| 1221 | { |
| 1222 | unsigned int x; |
| 1223 | int error = 0; |
| 1224 | |
| 1225 | for (x = 0; x < num_gh; x++) |
| 1226 | p[x] = &ghs[x]; |
| 1227 | |
| 1228 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); |
| 1229 | |
| 1230 | for (x = 0; x < num_gh; x++) { |
| 1231 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
| 1232 | |
| 1233 | error = gfs2_glock_nq(p[x]); |
| 1234 | if (error) { |
| 1235 | while (x--) |
| 1236 | gfs2_glock_dq(p[x]); |
| 1237 | break; |
| 1238 | } |
| 1239 | } |
| 1240 | |
| 1241 | return error; |
| 1242 | } |
| 1243 | |
| 1244 | /** |
| 1245 | * gfs2_glock_nq_m - acquire multiple glocks |
| 1246 | * @num_gh: the number of structures |
| 1247 | * @ghs: an array of struct gfs2_holder structures |
| 1248 | * |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1249 | * |
| 1250 | * Returns: 0 on success (all glocks acquired), |
| 1251 | * errno on failure (no glocks acquired) |
| 1252 | */ |
| 1253 | |
| 1254 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) |
| 1255 | { |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1256 | struct gfs2_holder *tmp[4]; |
| 1257 | struct gfs2_holder **pph = tmp; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1258 | int error = 0; |
| 1259 | |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1260 | switch(num_gh) { |
| 1261 | case 0: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1262 | return 0; |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1263 | case 1: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1264 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
| 1265 | return gfs2_glock_nq(ghs); |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1266 | default: |
| 1267 | if (num_gh <= 4) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1268 | break; |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1269 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
| 1270 | if (!pph) |
| 1271 | return -ENOMEM; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1272 | } |
| 1273 | |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1274 | error = nq_m_sync(num_gh, ghs, pph); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1275 | |
Steven Whitehouse | eaf5bd3 | 2007-06-19 15:38:17 +0100 | [diff] [blame] | 1276 | if (pph != tmp) |
| 1277 | kfree(pph); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1278 | |
| 1279 | return error; |
| 1280 | } |
| 1281 | |
| 1282 | /** |
| 1283 | * gfs2_glock_dq_m - release multiple glocks |
| 1284 | * @num_gh: the number of structures |
| 1285 | * @ghs: an array of struct gfs2_holder structures |
| 1286 | * |
| 1287 | */ |
| 1288 | |
| 1289 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) |
| 1290 | { |
| 1291 | unsigned int x; |
| 1292 | |
| 1293 | for (x = 0; x < num_gh; x++) |
| 1294 | gfs2_glock_dq(&ghs[x]); |
| 1295 | } |
| 1296 | |
| 1297 | /** |
| 1298 | * gfs2_glock_dq_uninit_m - release multiple glocks |
| 1299 | * @num_gh: the number of structures |
| 1300 | * @ghs: an array of struct gfs2_holder structures |
| 1301 | * |
| 1302 | */ |
| 1303 | |
| 1304 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) |
| 1305 | { |
| 1306 | unsigned int x; |
| 1307 | |
| 1308 | for (x = 0; x < num_gh; x++) |
| 1309 | gfs2_glock_dq_uninit(&ghs[x]); |
| 1310 | } |
| 1311 | |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1312 | void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state) |
Steven Whitehouse | da755fd | 2008-01-30 15:34:04 +0000 | [diff] [blame] | 1313 | { |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1314 | unsigned long delay = 0; |
| 1315 | unsigned long holdtime; |
| 1316 | unsigned long now = jiffies; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1317 | |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1318 | gfs2_glock_hold(gl); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1319 | holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time; |
Steven Whitehouse | 7b5e3d5 | 2010-09-03 09:39:20 +0100 | [diff] [blame] | 1320 | if (test_bit(GLF_QUEUED, &gl->gl_flags)) { |
| 1321 | if (time_before(now, holdtime)) |
| 1322 | delay = holdtime - now; |
| 1323 | if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags)) |
| 1324 | delay = gl->gl_ops->go_min_hold_time; |
| 1325 | } |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1326 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1327 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1328 | handle_callback(gl, state, delay); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1329 | spin_unlock(&gl->gl_spin); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1330 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
| 1331 | gfs2_glock_put(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1332 | } |
| 1333 | |
| 1334 | /** |
Steven Whitehouse | 0809f6e | 2010-08-02 10:15:17 +0100 | [diff] [blame] | 1335 | * gfs2_should_freeze - Figure out if glock should be frozen |
| 1336 | * @gl: The glock in question |
| 1337 | * |
| 1338 | * Glocks are not frozen if (a) the result of the dlm operation is |
| 1339 | * an error, (b) the locking operation was an unlock operation or |
| 1340 | * (c) if there is a "noexp" flagged request anywhere in the queue |
| 1341 | * |
| 1342 | * Returns: 1 if freezing should occur, 0 otherwise |
| 1343 | */ |
| 1344 | |
| 1345 | static int gfs2_should_freeze(const struct gfs2_glock *gl) |
| 1346 | { |
| 1347 | const struct gfs2_holder *gh; |
| 1348 | |
| 1349 | if (gl->gl_reply & ~LM_OUT_ST_MASK) |
| 1350 | return 0; |
| 1351 | if (gl->gl_target == LM_ST_UNLOCKED) |
| 1352 | return 0; |
| 1353 | |
| 1354 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { |
| 1355 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) |
| 1356 | continue; |
| 1357 | if (LM_FLAG_NOEXP & gh->gh_flags) |
| 1358 | return 0; |
| 1359 | } |
| 1360 | |
| 1361 | return 1; |
| 1362 | } |
| 1363 | |
| 1364 | /** |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1365 | * gfs2_glock_complete - Callback used by locking |
| 1366 | * @gl: Pointer to the glock |
| 1367 | * @ret: The return value from the dlm |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1368 | * |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1369 | */ |
| 1370 | |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1371 | void gfs2_glock_complete(struct gfs2_glock *gl, int ret) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1372 | { |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1373 | struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; |
Steven Whitehouse | 0809f6e | 2010-08-02 10:15:17 +0100 | [diff] [blame] | 1374 | |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1375 | gl->gl_reply = ret; |
Steven Whitehouse | 0809f6e | 2010-08-02 10:15:17 +0100 | [diff] [blame] | 1376 | |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1377 | if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_flags))) { |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1378 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | 0809f6e | 2010-08-02 10:15:17 +0100 | [diff] [blame] | 1379 | if (gfs2_should_freeze(gl)) { |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1380 | set_bit(GLF_FROZEN, &gl->gl_flags); |
Steven Whitehouse | 0809f6e | 2010-08-02 10:15:17 +0100 | [diff] [blame] | 1381 | spin_unlock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1382 | return; |
Steven Whitehouse | 0809f6e | 2010-08-02 10:15:17 +0100 | [diff] [blame] | 1383 | } |
| 1384 | spin_unlock(&gl->gl_spin); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1385 | } |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1386 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
| 1387 | gfs2_glock_hold(gl); |
| 1388 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
| 1389 | gfs2_glock_put(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1390 | } |
| 1391 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1392 | |
Dave Chinner | 7f8275d | 2010-07-19 14:56:17 +1000 | [diff] [blame] | 1393 | static int gfs2_shrink_glock_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1394 | { |
| 1395 | struct gfs2_glock *gl; |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1396 | int may_demote; |
| 1397 | int nr_skipped = 0; |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1398 | LIST_HEAD(skipped); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1399 | |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1400 | if (nr == 0) |
| 1401 | goto out; |
| 1402 | |
| 1403 | if (!(gfp_mask & __GFP_FS)) |
| 1404 | return -1; |
| 1405 | |
| 1406 | spin_lock(&lru_lock); |
| 1407 | while(nr && !list_empty(&lru_list)) { |
| 1408 | gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru); |
| 1409 | list_del_init(&gl->gl_lru); |
| 1410 | atomic_dec(&lru_count); |
| 1411 | |
| 1412 | /* Test for being demotable */ |
| 1413 | if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
| 1414 | gfs2_glock_hold(gl); |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1415 | spin_unlock(&lru_lock); |
| 1416 | spin_lock(&gl->gl_spin); |
| 1417 | may_demote = demote_ok(gl); |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1418 | if (may_demote) { |
| 1419 | handle_callback(gl, LM_ST_UNLOCKED, 0); |
| 1420 | nr--; |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1421 | } |
Steven Whitehouse | 7e71c55 | 2009-09-22 10:56:16 +0100 | [diff] [blame] | 1422 | clear_bit(GLF_LOCK, &gl->gl_flags); |
| 1423 | smp_mb__after_clear_bit(); |
Steven Whitehouse | 2163b1e | 2009-06-25 16:30:26 +0100 | [diff] [blame] | 1424 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 1425 | gfs2_glock_put_nolock(gl); |
| 1426 | spin_unlock(&gl->gl_spin); |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1427 | spin_lock(&lru_lock); |
Steven Whitehouse | 2163b1e | 2009-06-25 16:30:26 +0100 | [diff] [blame] | 1428 | continue; |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1429 | } |
Steven Whitehouse | 2163b1e | 2009-06-25 16:30:26 +0100 | [diff] [blame] | 1430 | nr_skipped++; |
| 1431 | list_add(&gl->gl_lru, &skipped); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1432 | } |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1433 | list_splice(&skipped, &lru_list); |
| 1434 | atomic_add(nr_skipped, &lru_count); |
| 1435 | spin_unlock(&lru_lock); |
| 1436 | out: |
| 1437 | return (atomic_read(&lru_count) / 100) * sysctl_vfs_cache_pressure; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1438 | } |
| 1439 | |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1440 | static struct shrinker glock_shrinker = { |
| 1441 | .shrink = gfs2_shrink_glock_memory, |
| 1442 | .seeks = DEFAULT_SEEKS, |
| 1443 | }; |
| 1444 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1445 | /** |
| 1446 | * examine_bucket - Call a function for glock in a hash bucket |
| 1447 | * @examiner: the function |
| 1448 | * @sdp: the filesystem |
| 1449 | * @bucket: the bucket |
| 1450 | * |
| 1451 | * Returns: 1 if the bucket has entries |
| 1452 | */ |
| 1453 | |
| 1454 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, |
Steven Whitehouse | 37b2fa6 | 2006-09-08 13:35:56 -0400 | [diff] [blame] | 1455 | unsigned int hash) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1456 | { |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1457 | struct gfs2_glock *gl, *prev = NULL; |
| 1458 | int has_entries = 0; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1459 | struct hlist_head *head = &gl_hash_table[hash].hb_list; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1460 | |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1461 | read_lock(gl_lock_addr(hash)); |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1462 | /* Can't use hlist_for_each_entry - don't want prefetch here */ |
| 1463 | if (hlist_empty(head)) |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1464 | goto out; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1465 | gl = list_entry(head->first, struct gfs2_glock, gl_list); |
| 1466 | while(1) { |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1467 | if (!sdp || gl->gl_sbd == sdp) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1468 | gfs2_glock_hold(gl); |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1469 | read_unlock(gl_lock_addr(hash)); |
| 1470 | if (prev) |
| 1471 | gfs2_glock_put(prev); |
| 1472 | prev = gl; |
| 1473 | examiner(gl); |
Steven Whitehouse | a833634 | 2006-09-14 13:57:38 -0400 | [diff] [blame] | 1474 | has_entries = 1; |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1475 | read_lock(gl_lock_addr(hash)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1476 | } |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1477 | if (gl->gl_list.next == NULL) |
| 1478 | break; |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1479 | gl = list_entry(gl->gl_list.next, struct gfs2_glock, gl_list); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1480 | } |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1481 | out: |
| 1482 | read_unlock(gl_lock_addr(hash)); |
| 1483 | if (prev) |
| 1484 | gfs2_glock_put(prev); |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1485 | cond_resched(); |
Steven Whitehouse | 2426443 | 2006-09-11 21:40:30 -0400 | [diff] [blame] | 1486 | return has_entries; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1487 | } |
| 1488 | |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1489 | |
| 1490 | /** |
| 1491 | * thaw_glock - thaw out a glock which has an unprocessed reply waiting |
| 1492 | * @gl: The glock to thaw |
| 1493 | * |
| 1494 | * N.B. When we freeze a glock, we leave a ref to the glock outstanding, |
| 1495 | * so this has to result in the ref count being dropped by one. |
| 1496 | */ |
| 1497 | |
| 1498 | static void thaw_glock(struct gfs2_glock *gl) |
| 1499 | { |
| 1500 | if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) |
| 1501 | return; |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1502 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
| 1503 | gfs2_glock_hold(gl); |
| 1504 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
| 1505 | gfs2_glock_put(gl); |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1506 | } |
| 1507 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1508 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1509 | * clear_glock - look at a glock and see if we can free it from glock cache |
| 1510 | * @gl: the glock to look at |
| 1511 | * |
| 1512 | */ |
| 1513 | |
| 1514 | static void clear_glock(struct gfs2_glock *gl) |
| 1515 | { |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1516 | spin_lock(&lru_lock); |
| 1517 | if (!list_empty(&gl->gl_lru)) { |
| 1518 | list_del_init(&gl->gl_lru); |
| 1519 | atomic_dec(&lru_count); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1520 | } |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1521 | spin_unlock(&lru_lock); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1522 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1523 | spin_lock(&gl->gl_spin); |
Steven Whitehouse | c741c45 | 2010-09-29 14:20:52 +0100 | [diff] [blame] | 1524 | if (gl->gl_state != LM_ST_UNLOCKED) |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1525 | handle_callback(gl, LM_ST_UNLOCKED, 0); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1526 | spin_unlock(&gl->gl_spin); |
| 1527 | gfs2_glock_hold(gl); |
| 1528 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
| 1529 | gfs2_glock_put(gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1530 | } |
| 1531 | |
| 1532 | /** |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1533 | * gfs2_glock_thaw - Thaw any frozen glocks |
| 1534 | * @sdp: The super block |
| 1535 | * |
| 1536 | */ |
| 1537 | |
| 1538 | void gfs2_glock_thaw(struct gfs2_sbd *sdp) |
| 1539 | { |
| 1540 | unsigned x; |
| 1541 | |
| 1542 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) |
| 1543 | examine_bucket(thaw_glock, sdp, x); |
| 1544 | } |
| 1545 | |
| 1546 | /** |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1547 | * gfs2_gl_hash_clear - Empty out the glock hash table |
| 1548 | * @sdp: the filesystem |
| 1549 | * @wait: wait until it's all gone |
| 1550 | * |
Steven Whitehouse | 1bdad60 | 2008-06-03 14:09:53 +0100 | [diff] [blame] | 1551 | * Called when unmounting the filesystem. |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1552 | */ |
| 1553 | |
Steven Whitehouse | fefc03b | 2008-12-19 15:32:06 +0000 | [diff] [blame] | 1554 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1555 | { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1556 | unsigned int x; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1557 | |
Steven Whitehouse | c1184f8 | 2010-01-08 16:14:29 +0000 | [diff] [blame] | 1558 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) |
| 1559 | examine_bucket(clear_glock, sdp, x); |
Steven Whitehouse | 8f05228 | 2010-01-29 15:21:27 +0000 | [diff] [blame] | 1560 | flush_workqueue(glock_workqueue); |
| 1561 | wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0); |
| 1562 | gfs2_dump_lockstate(sdp); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1563 | } |
| 1564 | |
Steven Whitehouse | 813e0c4 | 2008-11-18 13:38:48 +0000 | [diff] [blame] | 1565 | void gfs2_glock_finish_truncate(struct gfs2_inode *ip) |
| 1566 | { |
| 1567 | struct gfs2_glock *gl = ip->i_gl; |
| 1568 | int ret; |
| 1569 | |
| 1570 | ret = gfs2_truncatei_resume(ip); |
| 1571 | gfs2_assert_withdraw(gl->gl_sbd, ret == 0); |
| 1572 | |
| 1573 | spin_lock(&gl->gl_spin); |
| 1574 | clear_bit(GLF_LOCK, &gl->gl_flags); |
| 1575 | run_queue(gl, 1); |
| 1576 | spin_unlock(&gl->gl_spin); |
| 1577 | } |
| 1578 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1579 | static const char *state2str(unsigned state) |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1580 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1581 | switch(state) { |
| 1582 | case LM_ST_UNLOCKED: |
| 1583 | return "UN"; |
| 1584 | case LM_ST_SHARED: |
| 1585 | return "SH"; |
| 1586 | case LM_ST_DEFERRED: |
| 1587 | return "DF"; |
| 1588 | case LM_ST_EXCLUSIVE: |
| 1589 | return "EX"; |
| 1590 | } |
| 1591 | return "??"; |
| 1592 | } |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1593 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1594 | static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) |
| 1595 | { |
| 1596 | char *p = buf; |
| 1597 | if (flags & LM_FLAG_TRY) |
| 1598 | *p++ = 't'; |
| 1599 | if (flags & LM_FLAG_TRY_1CB) |
| 1600 | *p++ = 'T'; |
| 1601 | if (flags & LM_FLAG_NOEXP) |
| 1602 | *p++ = 'e'; |
| 1603 | if (flags & LM_FLAG_ANY) |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1604 | *p++ = 'A'; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1605 | if (flags & LM_FLAG_PRIORITY) |
| 1606 | *p++ = 'p'; |
| 1607 | if (flags & GL_ASYNC) |
| 1608 | *p++ = 'a'; |
| 1609 | if (flags & GL_EXACT) |
| 1610 | *p++ = 'E'; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1611 | if (flags & GL_NOCACHE) |
| 1612 | *p++ = 'c'; |
| 1613 | if (test_bit(HIF_HOLDER, &iflags)) |
| 1614 | *p++ = 'H'; |
| 1615 | if (test_bit(HIF_WAIT, &iflags)) |
| 1616 | *p++ = 'W'; |
| 1617 | if (test_bit(HIF_FIRST, &iflags)) |
| 1618 | *p++ = 'F'; |
| 1619 | *p = 0; |
| 1620 | return buf; |
Robert Peterson | 04b933f | 2007-03-23 17:05:15 -0500 | [diff] [blame] | 1621 | } |
| 1622 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1623 | /** |
| 1624 | * dump_holder - print information about a glock holder |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1625 | * @seq: the seq_file struct |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1626 | * @gh: the glock holder |
| 1627 | * |
| 1628 | * Returns: 0 on success, -ENOBUFS when we run out of space |
| 1629 | */ |
| 1630 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1631 | static int dump_holder(struct seq_file *seq, const struct gfs2_holder *gh) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1632 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1633 | struct task_struct *gh_owner = NULL; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1634 | char flags_buf[32]; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1635 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1636 | if (gh->gh_owner_pid) |
Pavel Emelyanov | b1e058d | 2008-02-07 00:13:19 -0800 | [diff] [blame] | 1637 | gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); |
Joe Perches | cc18152 | 2010-11-05 16:12:36 -0700 | [diff] [blame] | 1638 | gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n", |
| 1639 | state2str(gh->gh_state), |
| 1640 | hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), |
| 1641 | gh->gh_error, |
| 1642 | gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, |
| 1643 | gh_owner ? gh_owner->comm : "(ended)", |
| 1644 | (void *)gh->gh_ip); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1645 | return 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1646 | } |
| 1647 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1648 | static const char *gflags2str(char *buf, const unsigned long *gflags) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1649 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1650 | char *p = buf; |
| 1651 | if (test_bit(GLF_LOCK, gflags)) |
| 1652 | *p++ = 'l'; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1653 | if (test_bit(GLF_DEMOTE, gflags)) |
| 1654 | *p++ = 'D'; |
| 1655 | if (test_bit(GLF_PENDING_DEMOTE, gflags)) |
| 1656 | *p++ = 'd'; |
| 1657 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags)) |
| 1658 | *p++ = 'p'; |
| 1659 | if (test_bit(GLF_DIRTY, gflags)) |
| 1660 | *p++ = 'y'; |
| 1661 | if (test_bit(GLF_LFLUSH, gflags)) |
| 1662 | *p++ = 'f'; |
| 1663 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags)) |
| 1664 | *p++ = 'i'; |
| 1665 | if (test_bit(GLF_REPLY_PENDING, gflags)) |
| 1666 | *p++ = 'r'; |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1667 | if (test_bit(GLF_INITIAL, gflags)) |
Steven Whitehouse | d8348de | 2009-02-05 10:12:38 +0000 | [diff] [blame] | 1668 | *p++ = 'I'; |
Steven Whitehouse | f057f6c | 2009-01-12 10:43:39 +0000 | [diff] [blame] | 1669 | if (test_bit(GLF_FROZEN, gflags)) |
| 1670 | *p++ = 'F'; |
Steven Whitehouse | 7b5e3d5 | 2010-09-03 09:39:20 +0100 | [diff] [blame] | 1671 | if (test_bit(GLF_QUEUED, gflags)) |
| 1672 | *p++ = 'q'; |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1673 | *p = 0; |
| 1674 | return buf; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1675 | } |
| 1676 | |
| 1677 | /** |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1678 | * __dump_glock - print information about a glock |
| 1679 | * @seq: The seq_file struct |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1680 | * @gl: the glock |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1681 | * |
| 1682 | * The file format is as follows: |
| 1683 | * One line per object, capital letters are used to indicate objects |
| 1684 | * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented, |
| 1685 | * other objects are indented by a single space and follow the glock to |
| 1686 | * which they are related. Fields are indicated by lower case letters |
| 1687 | * followed by a colon and the field value, except for strings which are in |
| 1688 | * [] so that its possible to see if they are composed of spaces for |
| 1689 | * example. The field's are n = number (id of the object), f = flags, |
| 1690 | * t = type, s = state, r = refcount, e = error, p = pid. |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1691 | * |
| 1692 | * Returns: 0 on success, -ENOBUFS when we run out of space |
| 1693 | */ |
| 1694 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1695 | static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1696 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1697 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
| 1698 | unsigned long long dtime; |
| 1699 | const struct gfs2_holder *gh; |
| 1700 | char gflags_buf[32]; |
| 1701 | int error = 0; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1702 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1703 | dtime = jiffies - gl->gl_demote_time; |
| 1704 | dtime *= 1000000/HZ; /* demote time in uSec */ |
| 1705 | if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) |
| 1706 | dtime = 0; |
Bob Peterson | 4818972 | 2010-02-23 12:20:00 -0500 | [diff] [blame] | 1707 | gfs2_print_dbg(seq, "G: s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d r:%d\n", |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1708 | state2str(gl->gl_state), |
| 1709 | gl->gl_name.ln_type, |
| 1710 | (unsigned long long)gl->gl_name.ln_number, |
| 1711 | gflags2str(gflags_buf, &gl->gl_flags), |
| 1712 | state2str(gl->gl_target), |
| 1713 | state2str(gl->gl_demote_state), dtime, |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1714 | atomic_read(&gl->gl_ail_count), |
| 1715 | atomic_read(&gl->gl_ref)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1716 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1717 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1718 | error = dump_holder(seq, gh); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1719 | if (error) |
| 1720 | goto out; |
| 1721 | } |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1722 | if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump) |
| 1723 | error = glops->go_dump(seq, gl); |
Steven Whitehouse | a91ea69 | 2006-09-04 12:04:26 -0400 | [diff] [blame] | 1724 | out: |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1725 | return error; |
| 1726 | } |
| 1727 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1728 | static int dump_glock(struct seq_file *seq, struct gfs2_glock *gl) |
| 1729 | { |
| 1730 | int ret; |
| 1731 | spin_lock(&gl->gl_spin); |
| 1732 | ret = __dump_glock(seq, gl); |
| 1733 | spin_unlock(&gl->gl_spin); |
| 1734 | return ret; |
| 1735 | } |
| 1736 | |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1737 | /** |
| 1738 | * gfs2_dump_lockstate - print out the current lockstate |
| 1739 | * @sdp: the filesystem |
| 1740 | * @ub: the buffer to copy the information into |
| 1741 | * |
| 1742 | * If @ub is NULL, dump the lockstate to the console. |
| 1743 | * |
| 1744 | */ |
| 1745 | |
Adrian Bunk | 08bc2db | 2006-04-28 10:59:12 -0400 | [diff] [blame] | 1746 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp) |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1747 | { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1748 | struct gfs2_glock *gl; |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1749 | struct hlist_node *h; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1750 | unsigned int x; |
| 1751 | int error = 0; |
| 1752 | |
| 1753 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1754 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 1755 | read_lock(gl_lock_addr(x)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1756 | |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1757 | 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] | 1758 | if (gl->gl_sbd != sdp) |
| 1759 | continue; |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1760 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1761 | error = dump_glock(NULL, gl); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1762 | if (error) |
| 1763 | break; |
| 1764 | } |
| 1765 | |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 1766 | read_unlock(gl_lock_addr(x)); |
David Teigland | b3b94fa | 2006-01-16 16:50:04 +0000 | [diff] [blame] | 1767 | |
| 1768 | if (error) |
| 1769 | break; |
| 1770 | } |
| 1771 | |
| 1772 | |
| 1773 | return error; |
| 1774 | } |
| 1775 | |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1776 | |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 1777 | int __init gfs2_glock_init(void) |
| 1778 | { |
| 1779 | unsigned i; |
| 1780 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { |
Steven Whitehouse | b639789 | 2006-09-12 10:10:01 -0400 | [diff] [blame] | 1781 | INIT_HLIST_HEAD(&gl_hash_table[i].hb_list); |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 1782 | } |
Steven Whitehouse | 087efdd | 2006-09-09 16:59:11 -0400 | [diff] [blame] | 1783 | #ifdef GL_HASH_LOCK_SZ |
| 1784 | for(i = 0; i < GL_HASH_LOCK_SZ; i++) { |
| 1785 | rwlock_init(&gl_hash_locks[i]); |
| 1786 | } |
| 1787 | #endif |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1788 | |
Steven Whitehouse | d211577 | 2010-11-03 19:58:53 +0000 | [diff] [blame] | 1789 | glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM | |
Steven Whitehouse | 9fa0ea9 | 2010-09-13 16:23:00 +0100 | [diff] [blame] | 1790 | WQ_HIGHPRI | WQ_FREEZEABLE, 0); |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1791 | if (IS_ERR(glock_workqueue)) |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1792 | return PTR_ERR(glock_workqueue); |
Steven Whitehouse | d211577 | 2010-11-03 19:58:53 +0000 | [diff] [blame] | 1793 | gfs2_delete_workqueue = alloc_workqueue("delete_workqueue", |
| 1794 | WQ_MEM_RECLAIM | WQ_FREEZEABLE, |
| 1795 | 0); |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 1796 | if (IS_ERR(gfs2_delete_workqueue)) { |
| 1797 | destroy_workqueue(glock_workqueue); |
| 1798 | return PTR_ERR(gfs2_delete_workqueue); |
| 1799 | } |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1800 | |
| 1801 | register_shrinker(&glock_shrinker); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1802 | |
Steven Whitehouse | 85d1da6 | 2006-09-07 14:40:21 -0400 | [diff] [blame] | 1803 | return 0; |
| 1804 | } |
| 1805 | |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1806 | void gfs2_glock_exit(void) |
| 1807 | { |
Steven Whitehouse | 97cc102 | 2008-11-20 13:39:47 +0000 | [diff] [blame] | 1808 | unregister_shrinker(&glock_shrinker); |
Benjamin Marzinski | c4f68a1 | 2007-08-23 13:19:05 -0500 | [diff] [blame] | 1809 | destroy_workqueue(glock_workqueue); |
Benjamin Marzinski | b94a170 | 2009-07-23 18:52:34 -0500 | [diff] [blame] | 1810 | destroy_workqueue(gfs2_delete_workqueue); |
Steven Whitehouse | 8fbbfd2 | 2007-08-01 13:57:10 +0100 | [diff] [blame] | 1811 | } |
| 1812 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1813 | static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1814 | { |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 1815 | struct gfs2_glock *gl; |
| 1816 | |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 1817 | restart: |
Robert Peterson | 7a0079d | 2007-04-17 11:37:11 -0500 | [diff] [blame] | 1818 | read_lock(gl_lock_addr(gi->hash)); |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 1819 | gl = gi->gl; |
| 1820 | if (gl) { |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 1821 | gi->gl = hlist_entry(gl->gl_list.next, |
| 1822 | struct gfs2_glock, gl_list); |
Steven Whitehouse | c1e817d | 2008-07-22 22:58:03 +0100 | [diff] [blame] | 1823 | } else { |
| 1824 | gi->gl = hlist_entry(gl_hash_table[gi->hash].hb_list.first, |
| 1825 | struct gfs2_glock, gl_list); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1826 | } |
Steven Whitehouse | c1e817d | 2008-07-22 22:58:03 +0100 | [diff] [blame] | 1827 | if (gi->gl) |
| 1828 | gfs2_glock_hold(gi->gl); |
Robert Peterson | 7a0079d | 2007-04-17 11:37:11 -0500 | [diff] [blame] | 1829 | read_unlock(gl_lock_addr(gi->hash)); |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 1830 | if (gl) |
| 1831 | gfs2_glock_put(gl); |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1832 | while (gi->gl == NULL) { |
Steven Whitehouse | c1e817d | 2008-07-22 22:58:03 +0100 | [diff] [blame] | 1833 | gi->hash++; |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 1834 | if (gi->hash >= GFS2_GL_HASH_SIZE) |
| 1835 | return 1; |
| 1836 | read_lock(gl_lock_addr(gi->hash)); |
| 1837 | gi->gl = hlist_entry(gl_hash_table[gi->hash].hb_list.first, |
| 1838 | struct gfs2_glock, gl_list); |
| 1839 | if (gi->gl) |
| 1840 | gfs2_glock_hold(gi->gl); |
| 1841 | read_unlock(gl_lock_addr(gi->hash)); |
| 1842 | } |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 1843 | |
| 1844 | if (gi->sdp != gi->gl->gl_sbd) |
| 1845 | goto restart; |
| 1846 | |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1847 | return 0; |
| 1848 | } |
| 1849 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1850 | static void gfs2_glock_iter_free(struct gfs2_glock_iter *gi) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1851 | { |
Steven Whitehouse | 7b08fc6 | 2007-07-24 13:53:36 +0100 | [diff] [blame] | 1852 | if (gi->gl) |
| 1853 | gfs2_glock_put(gi->gl); |
Abhijith Das | a947e03 | 2007-08-21 09:57:29 -0500 | [diff] [blame] | 1854 | gi->gl = NULL; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1855 | } |
| 1856 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1857 | static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1858 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1859 | struct gfs2_glock_iter *gi = seq->private; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1860 | loff_t n = *pos; |
| 1861 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1862 | gi->hash = 0; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1863 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1864 | do { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1865 | if (gfs2_glock_iter_next(gi)) { |
| 1866 | gfs2_glock_iter_free(gi); |
| 1867 | return NULL; |
| 1868 | } |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1869 | } while (n--); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1870 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1871 | return gi->gl; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1872 | } |
| 1873 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1874 | static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr, |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1875 | loff_t *pos) |
| 1876 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1877 | struct gfs2_glock_iter *gi = seq->private; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1878 | |
| 1879 | (*pos)++; |
| 1880 | |
| 1881 | if (gfs2_glock_iter_next(gi)) { |
| 1882 | gfs2_glock_iter_free(gi); |
| 1883 | return NULL; |
| 1884 | } |
| 1885 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1886 | return gi->gl; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1887 | } |
| 1888 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1889 | static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1890 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1891 | struct gfs2_glock_iter *gi = seq->private; |
| 1892 | gfs2_glock_iter_free(gi); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1893 | } |
| 1894 | |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1895 | static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1896 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1897 | return dump_glock(seq, iter_ptr); |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1898 | } |
| 1899 | |
Denis Cheng | 4ef2900 | 2007-07-31 18:31:11 +0800 | [diff] [blame] | 1900 | static const struct seq_operations gfs2_glock_seq_ops = { |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1901 | .start = gfs2_glock_seq_start, |
| 1902 | .next = gfs2_glock_seq_next, |
| 1903 | .stop = gfs2_glock_seq_stop, |
| 1904 | .show = gfs2_glock_seq_show, |
| 1905 | }; |
| 1906 | |
| 1907 | static int gfs2_debugfs_open(struct inode *inode, struct file *file) |
| 1908 | { |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1909 | int ret = seq_open_private(file, &gfs2_glock_seq_ops, |
| 1910 | sizeof(struct gfs2_glock_iter)); |
| 1911 | if (ret == 0) { |
| 1912 | struct seq_file *seq = file->private_data; |
| 1913 | struct gfs2_glock_iter *gi = seq->private; |
| 1914 | gi->sdp = inode->i_private; |
| 1915 | } |
| 1916 | return ret; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1917 | } |
| 1918 | |
| 1919 | static const struct file_operations gfs2_debug_fops = { |
| 1920 | .owner = THIS_MODULE, |
| 1921 | .open = gfs2_debugfs_open, |
| 1922 | .read = seq_read, |
| 1923 | .llseek = seq_lseek, |
Steven Whitehouse | 6802e34 | 2008-05-21 17:03:22 +0100 | [diff] [blame] | 1924 | .release = seq_release_private, |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1925 | }; |
| 1926 | |
| 1927 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) |
| 1928 | { |
Robert Peterson | 5f88209 | 2007-04-18 11:41:11 -0500 | [diff] [blame] | 1929 | sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root); |
| 1930 | if (!sdp->debugfs_dir) |
| 1931 | return -ENOMEM; |
| 1932 | sdp->debugfs_dentry_glocks = debugfs_create_file("glocks", |
| 1933 | S_IFREG | S_IRUGO, |
| 1934 | sdp->debugfs_dir, sdp, |
| 1935 | &gfs2_debug_fops); |
| 1936 | if (!sdp->debugfs_dentry_glocks) |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1937 | return -ENOMEM; |
| 1938 | |
| 1939 | return 0; |
| 1940 | } |
| 1941 | |
| 1942 | void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp) |
| 1943 | { |
Robert Peterson | 5f88209 | 2007-04-18 11:41:11 -0500 | [diff] [blame] | 1944 | if (sdp && sdp->debugfs_dir) { |
| 1945 | if (sdp->debugfs_dentry_glocks) { |
| 1946 | debugfs_remove(sdp->debugfs_dentry_glocks); |
| 1947 | sdp->debugfs_dentry_glocks = NULL; |
| 1948 | } |
| 1949 | debugfs_remove(sdp->debugfs_dir); |
| 1950 | sdp->debugfs_dir = NULL; |
| 1951 | } |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1952 | } |
| 1953 | |
| 1954 | int gfs2_register_debugfs(void) |
| 1955 | { |
| 1956 | gfs2_root = debugfs_create_dir("gfs2", NULL); |
| 1957 | return gfs2_root ? 0 : -ENOMEM; |
| 1958 | } |
| 1959 | |
| 1960 | void gfs2_unregister_debugfs(void) |
| 1961 | { |
| 1962 | debugfs_remove(gfs2_root); |
Robert Peterson | 5f88209 | 2007-04-18 11:41:11 -0500 | [diff] [blame] | 1963 | gfs2_root = NULL; |
Robert Peterson | 7c52b16 | 2007-03-16 10:26:37 +0000 | [diff] [blame] | 1964 | } |