fs/ocfs2/stack_o2cb.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * stack_o2cb.c
   4  *
   5  * Code which interfaces ocfs2 with the o2cb stack.
   6  *
   7  * Copyright (C) 2007 Oracle.  All rights reserved.
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/crc32.h>
  12 #include <linux/slab.h>
  13 #include <linux/module.h>
  14
  15 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
  16 #include <linux/fs.h>
  17
  18 #include "cluster/masklog.h"
  19 #include "cluster/nodemanager.h"
  20 #include "cluster/heartbeat.h"
  21 #include "cluster/tcp.h"
  22
  23 #include "stackglue.h"
  24
  25 struct o2dlm_private {
  26         struct dlm_eviction_cb op_eviction_cb;
  27 };
  28
  29 static struct ocfs2_stack_plugin o2cb_stack;
  30
  31 /* These should be identical */
  32 #if (DLM_LOCK_IV != LKM_IVMODE)
  33 # error Lock modes do not match
  34 #endif
  35 #if (DLM_LOCK_NL != LKM_NLMODE)
  36 # error Lock modes do not match
  37 #endif
  38 #if (DLM_LOCK_CR != LKM_CRMODE)
  39 # error Lock modes do not match
  40 #endif
  41 #if (DLM_LOCK_CW != LKM_CWMODE)
  42 # error Lock modes do not match
  43 #endif
  44 #if (DLM_LOCK_PR != LKM_PRMODE)
  45 # error Lock modes do not match
  46 #endif
  47 #if (DLM_LOCK_PW != LKM_PWMODE)
  48 # error Lock modes do not match
  49 #endif
  50 #if (DLM_LOCK_EX != LKM_EXMODE)
  51 # error Lock modes do not match
  52 #endif
  53 static inline int mode_to_o2dlm(int mode)
  54 {
  55         BUG_ON(mode > LKM_MAXMODE);
  56
  57         return mode;
  58 }
  59
  60 static int flags_to_o2dlm(u32 flags)
  61 {
  62         int o2dlm_flags = 0;
  63
  64         if (flags & DLM_LKF_NOQUEUE)
  65                 o2dlm_flags |= LKM_NOQUEUE;
  66         if (flags & DLM_LKF_CANCEL)
  67                 o2dlm_flags |= LKM_CANCEL;
  68         if (flags & DLM_LKF_CONVERT)
  69                 o2dlm_flags |= LKM_CONVERT;
  70         if (flags & DLM_LKF_VALBLK)
  71                 o2dlm_flags |= LKM_VALBLK;
  72         if (flags & DLM_LKF_IVVALBLK)
  73                 o2dlm_flags |= LKM_INVVALBLK;
  74         if (flags & DLM_LKF_ORPHAN)
  75                 o2dlm_flags |= LKM_ORPHAN;
  76         if (flags & DLM_LKF_FORCEUNLOCK)
  77                 o2dlm_flags |= LKM_FORCE;
  78         if (flags & DLM_LKF_TIMEOUT)
  79                 o2dlm_flags |= LKM_TIMEOUT;
  80         if (flags & DLM_LKF_LOCAL)
  81                 o2dlm_flags |= LKM_LOCAL;
  82
  83         return o2dlm_flags;
  84 }
  85
  86 /*
  87  * Map an o2dlm status to standard errno values.
  88  *
  89  * o2dlm only uses a handful of these, and returns even fewer to the
  90  * caller. Still, we try to assign sane values to each error.
  91  *
  92  * The following value pairs have special meanings to dlmglue, thus
  93  * the right hand side needs to stay unique - never duplicate the
  94  * mapping elsewhere in the table!
  95  *
  96  * DLM_NORMAL:          0
  97  * DLM_NOTQUEUED:       -EAGAIN
  98  * DLM_CANCELGRANT:     -EBUSY
  99  * DLM_CANCEL:          -DLM_ECANCEL
 100  */
 101 /* Keep in sync with dlmapi.h */
 102 static int status_map[] = {
 103         [DLM_NORMAL]                    = 0,            /* Success */
 104         [DLM_GRANTED]                   = -EINVAL,
 105         [DLM_DENIED]                    = -EACCES,
 106         [DLM_DENIED_NOLOCKS]            = -EACCES,
 107         [DLM_WORKING]                   = -EACCES,
 108         [DLM_BLOCKED]                   = -EINVAL,
 109         [DLM_BLOCKED_ORPHAN]            = -EINVAL,
 110         [DLM_DENIED_GRACE_PERIOD]       = -EACCES,
 111         [DLM_SYSERR]                    = -ENOMEM,      /* It is what it is */
 112         [DLM_NOSUPPORT]                 = -EPROTO,
 113         [DLM_CANCELGRANT]               = -EBUSY,       /* Cancel after grant */
 114         [DLM_IVLOCKID]                  = -EINVAL,
 115         [DLM_SYNC]                      = -EINVAL,
 116         [DLM_BADTYPE]                   = -EINVAL,
 117         [DLM_BADRESOURCE]               = -EINVAL,
 118         [DLM_MAXHANDLES]                = -ENOMEM,
 119         [DLM_NOCLINFO]                  = -EINVAL,
 120         [DLM_NOLOCKMGR]                 = -EINVAL,
 121         [DLM_NOPURGED]                  = -EINVAL,
 122         [DLM_BADARGS]                   = -EINVAL,
 123         [DLM_VOID]                      = -EINVAL,
 124         [DLM_NOTQUEUED]                 = -EAGAIN,      /* Trylock failed */
 125         [DLM_IVBUFLEN]                  = -EINVAL,
 126         [DLM_CVTUNGRANT]                = -EPERM,
 127         [DLM_BADPARAM]                  = -EINVAL,
 128         [DLM_VALNOTVALID]               = -EINVAL,
 129         [DLM_REJECTED]                  = -EPERM,
 130         [DLM_ABORT]                     = -EINVAL,
 131         [DLM_CANCEL]                    = -DLM_ECANCEL, /* Successful cancel */
 132         [DLM_IVRESHANDLE]               = -EINVAL,
 133         [DLM_DEADLOCK]                  = -EDEADLK,
 134         [DLM_DENIED_NOASTS]             = -EINVAL,
 135         [DLM_FORWARD]                   = -EINVAL,
 136         [DLM_TIMEOUT]                   = -ETIMEDOUT,
 137         [DLM_IVGROUPID]                 = -EINVAL,
 138         [DLM_VERS_CONFLICT]             = -EOPNOTSUPP,
 139         [DLM_BAD_DEVICE_PATH]           = -ENOENT,
 140         [DLM_NO_DEVICE_PERMISSION]      = -EPERM,
 141         [DLM_NO_CONTROL_DEVICE]         = -ENOENT,
 142         [DLM_RECOVERING]                = -ENOTCONN,
 143         [DLM_MIGRATING]                 = -ERESTART,
 144         [DLM_MAXSTATS]                  = -EINVAL,
 145 };
 146
 147 static int dlm_status_to_errno(enum dlm_status status)
 148 {
 149         BUG_ON(status < 0 || status >= ARRAY_SIZE(status_map));
 150
 151         return status_map[status];
 152 }
 153
 154 static void o2dlm_lock_ast_wrapper(void *astarg)
 155 {
 156         struct ocfs2_dlm_lksb *lksb = astarg;
 157
 158         lksb->lksb_conn->cc_proto->lp_lock_ast(lksb);
 159 }
 160
 161 static void o2dlm_blocking_ast_wrapper(void *astarg, int level)
 162 {
 163         struct ocfs2_dlm_lksb *lksb = astarg;
 164
 165         lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level);
 166 }
 167
 168 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
 169 {
 170         struct ocfs2_dlm_lksb *lksb = astarg;
 171         int error = dlm_status_to_errno(status);
 172
 173         /*
 174          * In o2dlm, you can get both the lock_ast() for the lock being
 175          * granted and the unlock_ast() for the CANCEL failing.  A
 176          * successful cancel sends DLM_NORMAL here.  If the
 177          * lock grant happened before the cancel arrived, you get
 178          * DLM_CANCELGRANT.
 179          *
 180          * There's no need for the double-ast.  If we see DLM_CANCELGRANT,
 181          * we just ignore it.  We expect the lock_ast() to handle the
 182          * granted lock.
 183          */
 184         if (status == DLM_CANCELGRANT)
 185                 return;
 186
 187         lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, error);
 188 }
 189
 190 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn,
 191                          int mode,
 192                          struct ocfs2_dlm_lksb *lksb,
 193                          u32 flags,
 194                          void *name,
 195                          unsigned int namelen)
 196 {
 197         enum dlm_status status;
 198         int o2dlm_mode = mode_to_o2dlm(mode);
 199         int o2dlm_flags = flags_to_o2dlm(flags);
 200         int ret;
 201
 202         status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
 203                          o2dlm_flags, name, namelen,
 204                          o2dlm_lock_ast_wrapper, lksb,
 205                          o2dlm_blocking_ast_wrapper);
 206         ret = dlm_status_to_errno(status);
 207         return ret;
 208 }
 209
 210 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
 211                            struct ocfs2_dlm_lksb *lksb,
 212                            u32 flags)
 213 {
 214         enum dlm_status status;
 215         int o2dlm_flags = flags_to_o2dlm(flags);
 216         int ret;
 217
 218         status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
 219                            o2dlm_flags, o2dlm_unlock_ast_wrapper, lksb);
 220         ret = dlm_status_to_errno(status);
 221         return ret;
 222 }
 223
 224 static int o2cb_dlm_lock_status(struct ocfs2_dlm_lksb *lksb)
 225 {
 226         return dlm_status_to_errno(lksb->lksb_o2dlm.status);
 227 }
 228
 229 /*
 230  * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB
 231  * contents, it will zero out the LVB.  Thus the caller can always trust
 232  * the contents.
 233  */
 234 static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
 235 {
 236         return 1;
 237 }
 238
 239 static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
 240 {
 241         return (void *)(lksb->lksb_o2dlm.lvb);
 242 }
 243
 244 static void o2cb_dump_lksb(struct ocfs2_dlm_lksb *lksb)
 245 {
 246         dlm_print_one_lock(lksb->lksb_o2dlm.lockid);
 247 }
 248
 249 /*
 250  * Check if this node is heartbeating and is connected to all other
 251  * heartbeating nodes.
 252  */
 253 static int o2cb_cluster_check(void)
 254 {
 255         u8 node_num;
 256         int i;
 257         unsigned long hbmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
 258         unsigned long netmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
 259
 260         node_num = o2nm_this_node();
 261         if (node_num == O2NM_MAX_NODES) {
 262                 printk(KERN_ERR "o2cb: This node has not been configured.\n");
 263                 return -EINVAL;
 264         }
 265
 266         /*
 267          * o2dlm expects o2net sockets to be created. If not, then
 268          * dlm_join_domain() fails with a stack of errors which are both cryptic
 269          * and incomplete. The idea here is to detect upfront whether we have
 270          * managed to connect to all nodes or not. If not, then list the nodes
 271          * to allow the user to check the configuration (incorrect IP, firewall,
 272          * etc.) Yes, this is racy. But its not the end of the world.
 273          */
 274 #define O2CB_MAP_STABILIZE_COUNT        60
 275         for (i = 0; i < O2CB_MAP_STABILIZE_COUNT; ++i) {
 276                 o2hb_fill_node_map(hbmap, O2NM_MAX_NODES);
 277                 if (!test_bit(node_num, hbmap)) {
 278                         printk(KERN_ERR "o2cb: %s heartbeat has not been "
 279                                "started.\n", (o2hb_global_heartbeat_active() ?
 280                                               "Global" : "Local"));
 281                         return -EINVAL;
 282                 }
 283                 o2net_fill_node_map(netmap, O2NM_MAX_NODES);
 284                 /* Force set the current node to allow easy compare */
 285                 set_bit(node_num, netmap);
 286                 if (bitmap_equal(hbmap, netmap, O2NM_MAX_NODES))
 287                         return 0;
 288                 if (i < O2CB_MAP_STABILIZE_COUNT - 1)
 289                         msleep(1000);
 290         }
 291
 292         printk(KERN_ERR "o2cb: This node could not connect to nodes:");
 293         i = -1;
 294         while ((i = find_next_bit(hbmap, O2NM_MAX_NODES,
 295                                   i + 1)) < O2NM_MAX_NODES) {
 296                 if (!test_bit(i, netmap))
 297                         printk(" %u", i);
 298         }
 299         printk(".\n");
 300
 301         return -ENOTCONN;
 302 }
 303
 304 /*
 305  * Called from the dlm when it's about to evict a node. This is how the
 306  * classic stack signals node death.
 307  */
 308 static void o2dlm_eviction_cb(int node_num, void *data)
 309 {
 310         struct ocfs2_cluster_connection *conn = data;
 311
 312         printk(KERN_NOTICE "o2cb: o2dlm has evicted node %d from domain %.*s\n",
 313                node_num, conn->cc_namelen, conn->cc_name);
 314
 315         conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
 316 }
 317
 318 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
 319 {
 320         int rc = 0;
 321         u32 dlm_key;
 322         struct dlm_ctxt *dlm;
 323         struct o2dlm_private *priv;
 324         struct dlm_protocol_version fs_version;
 325
 326         BUG_ON(conn == NULL);
 327         BUG_ON(conn->cc_proto == NULL);
 328
 329         /* Ensure cluster stack is up and all nodes are connected */
 330         rc = o2cb_cluster_check();
 331         if (rc) {
 332                 printk(KERN_ERR "o2cb: Cluster check failed. Fix errors "
 333                        "before retrying.\n");
 334                 goto out;
 335         }
 336
 337         priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
 338         if (!priv) {
 339                 rc = -ENOMEM;
 340                 goto out_free;
 341         }
 342
 343         /* This just fills the structure in.  It is safe to pass conn. */
 344         dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
 345                               conn);
 346
 347         conn->cc_private = priv;
 348
 349         /* used by the dlm code to make message headers unique, each
 350          * node in this domain must agree on this. */
 351         dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen);
 352         fs_version.pv_major = conn->cc_version.pv_major;
 353         fs_version.pv_minor = conn->cc_version.pv_minor;
 354
 355         dlm = dlm_register_domain(conn->cc_name, dlm_key, &fs_version);
 356         if (IS_ERR(dlm)) {
 357                 rc = PTR_ERR(dlm);
 358                 mlog_errno(rc);
 359                 goto out_free;
 360         }
 361
 362         conn->cc_version.pv_major = fs_version.pv_major;
 363         conn->cc_version.pv_minor = fs_version.pv_minor;
 364         conn->cc_lockspace = dlm;
 365
 366         dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
 367
 368 out_free:
 369         if (rc)
 370                 kfree(conn->cc_private);
 371
 372 out:
 373         return rc;
 374 }
 375
 376 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn)
 377 {
 378         struct dlm_ctxt *dlm = conn->cc_lockspace;
 379         struct o2dlm_private *priv = conn->cc_private;
 380
 381         dlm_unregister_eviction_cb(&priv->op_eviction_cb);
 382         conn->cc_private = NULL;
 383         kfree(priv);
 384
 385         dlm_unregister_domain(dlm);
 386         conn->cc_lockspace = NULL;
 387
 388         return 0;
 389 }
 390
 391 static int o2cb_cluster_this_node(struct ocfs2_cluster_connection *conn,
 392                                   unsigned int *node)
 393 {
 394         int node_num;
 395
 396         node_num = o2nm_this_node();
 397         if (node_num == O2NM_INVALID_NODE_NUM)
 398                 return -ENOENT;
 399
 400         if (node_num >= O2NM_MAX_NODES)
 401                 return -EOVERFLOW;
 402
 403         *node = node_num;
 404         return 0;
 405 }
 406
 407 static const struct ocfs2_stack_operations o2cb_stack_ops = {
 408         .connect        = o2cb_cluster_connect,
 409         .disconnect     = o2cb_cluster_disconnect,
 410         .this_node      = o2cb_cluster_this_node,
 411         .dlm_lock       = o2cb_dlm_lock,
 412         .dlm_unlock     = o2cb_dlm_unlock,
 413         .lock_status    = o2cb_dlm_lock_status,
 414         .lvb_valid      = o2cb_dlm_lvb_valid,
 415         .lock_lvb       = o2cb_dlm_lvb,
 416         .dump_lksb      = o2cb_dump_lksb,
 417 };
 418
 419 static struct ocfs2_stack_plugin o2cb_stack = {
 420         .sp_name        = "o2cb",
 421         .sp_ops         = &o2cb_stack_ops,
 422         .sp_owner       = THIS_MODULE,
 423 };
 424
 425 static int __init o2cb_stack_init(void)
 426 {
 427         return ocfs2_stack_glue_register(&o2cb_stack);
 428 }
 429
 430 static void __exit o2cb_stack_exit(void)
 431 {
 432         ocfs2_stack_glue_unregister(&o2cb_stack);
 433 }
 434
 435 MODULE_AUTHOR("Oracle");
 436 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack");
 437 MODULE_LICENSE("GPL");
 438 module_init(o2cb_stack_init);
 439 module_exit(o2cb_stack_exit);