fs/ocfs2/stack_o2cb.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* -*- mode: c; c-basic-offset: 8; -*-
   3  * vim: noexpandtab sw=8 ts=8 sts=0:
   4  *
   5  * stack_o2cb.c
   6  *
   7  * Code which interfaces ocfs2 with the o2cb stack.
   8  *
   9  * Copyright (C) 2007 Oracle.  All rights reserved.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/crc32.h>
  14 #include <linux/slab.h>
  15 #include <linux/module.h>
  16
  17 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
  18 #include <linux/fs.h>
  19
  20 #include "cluster/masklog.h"
  21 #include "cluster/nodemanager.h"
  22 #include "cluster/heartbeat.h"
  23 #include "cluster/tcp.h"
  24
  25 #include "stackglue.h"
  26
  27 struct o2dlm_private {
  28         struct dlm_eviction_cb op_eviction_cb;
  29 };
  30
  31 static struct ocfs2_stack_plugin o2cb_stack;
  32
  33 /* These should be identical */
  34 #if (DLM_LOCK_IV != LKM_IVMODE)
  35 # error Lock modes do not match
  36 #endif
  37 #if (DLM_LOCK_NL != LKM_NLMODE)
  38 # error Lock modes do not match
  39 #endif
  40 #if (DLM_LOCK_CR != LKM_CRMODE)
  41 # error Lock modes do not match
  42 #endif
  43 #if (DLM_LOCK_CW != LKM_CWMODE)
  44 # error Lock modes do not match
  45 #endif
  46 #if (DLM_LOCK_PR != LKM_PRMODE)
  47 # error Lock modes do not match
  48 #endif
  49 #if (DLM_LOCK_PW != LKM_PWMODE)
  50 # error Lock modes do not match
  51 #endif
  52 #if (DLM_LOCK_EX != LKM_EXMODE)
  53 # error Lock modes do not match
  54 #endif
  55 static inline int mode_to_o2dlm(int mode)
  56 {
  57         BUG_ON(mode > LKM_MAXMODE);
  58
  59         return mode;
  60 }
  61
  62 #define map_flag(_generic, _o2dlm)              \
  63         if (flags & (_generic)) {               \
  64                 flags &= ~(_generic);           \
  65                 o2dlm_flags |= (_o2dlm);        \
  66         }
  67 static int flags_to_o2dlm(u32 flags)
  68 {
  69         int o2dlm_flags = 0;
  70
  71         map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE);
  72         map_flag(DLM_LKF_CANCEL, LKM_CANCEL);
  73         map_flag(DLM_LKF_CONVERT, LKM_CONVERT);
  74         map_flag(DLM_LKF_VALBLK, LKM_VALBLK);
  75         map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK);
  76         map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN);
  77         map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE);
  78         map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT);
  79         map_flag(DLM_LKF_LOCAL, LKM_LOCAL);
  80
  81         /* map_flag() should have cleared every flag passed in */
  82         BUG_ON(flags != 0);
  83
  84         return o2dlm_flags;
  85 }
  86 #undef map_flag
  87
  88 /*
  89  * Map an o2dlm status to standard errno values.
  90  *
  91  * o2dlm only uses a handful of these, and returns even fewer to the
  92  * caller. Still, we try to assign sane values to each error.
  93  *
  94  * The following value pairs have special meanings to dlmglue, thus
  95  * the right hand side needs to stay unique - never duplicate the
  96  * mapping elsewhere in the table!
  97  *
  98  * DLM_NORMAL:          0
  99  * DLM_NOTQUEUED:       -EAGAIN
 100  * DLM_CANCELGRANT:     -EBUSY
 101  * DLM_CANCEL:          -DLM_ECANCEL
 102  */
 103 /* Keep in sync with dlmapi.h */
 104 static int status_map[] = {
 105         [DLM_NORMAL]                    = 0,            /* Success */
 106         [DLM_GRANTED]                   = -EINVAL,
 107         [DLM_DENIED]                    = -EACCES,
 108         [DLM_DENIED_NOLOCKS]            = -EACCES,
 109         [DLM_WORKING]                   = -EACCES,
 110         [DLM_BLOCKED]                   = -EINVAL,
 111         [DLM_BLOCKED_ORPHAN]            = -EINVAL,
 112         [DLM_DENIED_GRACE_PERIOD]       = -EACCES,
 113         [DLM_SYSERR]                    = -ENOMEM,      /* It is what it is */
 114         [DLM_NOSUPPORT]                 = -EPROTO,
 115         [DLM_CANCELGRANT]               = -EBUSY,       /* Cancel after grant */
 116         [DLM_IVLOCKID]                  = -EINVAL,
 117         [DLM_SYNC]                      = -EINVAL,
 118         [DLM_BADTYPE]                   = -EINVAL,
 119         [DLM_BADRESOURCE]               = -EINVAL,
 120         [DLM_MAXHANDLES]                = -ENOMEM,
 121         [DLM_NOCLINFO]                  = -EINVAL,
 122         [DLM_NOLOCKMGR]                 = -EINVAL,
 123         [DLM_NOPURGED]                  = -EINVAL,
 124         [DLM_BADARGS]                   = -EINVAL,
 125         [DLM_VOID]                      = -EINVAL,
 126         [DLM_NOTQUEUED]                 = -EAGAIN,      /* Trylock failed */
 127         [DLM_IVBUFLEN]                  = -EINVAL,
 128         [DLM_CVTUNGRANT]                = -EPERM,
 129         [DLM_BADPARAM]                  = -EINVAL,
 130         [DLM_VALNOTVALID]               = -EINVAL,
 131         [DLM_REJECTED]                  = -EPERM,
 132         [DLM_ABORT]                     = -EINVAL,
 133         [DLM_CANCEL]                    = -DLM_ECANCEL, /* Successful cancel */
 134         [DLM_IVRESHANDLE]               = -EINVAL,
 135         [DLM_DEADLOCK]                  = -EDEADLK,
 136         [DLM_DENIED_NOASTS]             = -EINVAL,
 137         [DLM_FORWARD]                   = -EINVAL,
 138         [DLM_TIMEOUT]                   = -ETIMEDOUT,
 139         [DLM_IVGROUPID]                 = -EINVAL,
 140         [DLM_VERS_CONFLICT]             = -EOPNOTSUPP,
 141         [DLM_BAD_DEVICE_PATH]           = -ENOENT,
 142         [DLM_NO_DEVICE_PERMISSION]      = -EPERM,
 143         [DLM_NO_CONTROL_DEVICE]         = -ENOENT,
 144         [DLM_RECOVERING]                = -ENOTCONN,
 145         [DLM_MIGRATING]                 = -ERESTART,
 146         [DLM_MAXSTATS]                  = -EINVAL,
 147 };
 148
 149 static int dlm_status_to_errno(enum dlm_status status)
 150 {
 151         BUG_ON(status < 0 || status >= ARRAY_SIZE(status_map));
 152
 153         return status_map[status];
 154 }
 155
 156 static void o2dlm_lock_ast_wrapper(void *astarg)
 157 {
 158         struct ocfs2_dlm_lksb *lksb = astarg;
 159
 160         lksb->lksb_conn->cc_proto->lp_lock_ast(lksb);
 161 }
 162
 163 static void o2dlm_blocking_ast_wrapper(void *astarg, int level)
 164 {
 165         struct ocfs2_dlm_lksb *lksb = astarg;
 166
 167         lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level);
 168 }
 169
 170 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
 171 {
 172         struct ocfs2_dlm_lksb *lksb = astarg;
 173         int error = dlm_status_to_errno(status);
 174
 175         /*
 176          * In o2dlm, you can get both the lock_ast() for the lock being
 177          * granted and the unlock_ast() for the CANCEL failing.  A
 178          * successful cancel sends DLM_NORMAL here.  If the
 179          * lock grant happened before the cancel arrived, you get
 180          * DLM_CANCELGRANT.
 181          *
 182          * There's no need for the double-ast.  If we see DLM_CANCELGRANT,
 183          * we just ignore it.  We expect the lock_ast() to handle the
 184          * granted lock.
 185          */
 186         if (status == DLM_CANCELGRANT)
 187                 return;
 188
 189         lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, error);
 190 }
 191
 192 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn,
 193                          int mode,
 194                          struct ocfs2_dlm_lksb *lksb,
 195                          u32 flags,
 196                          void *name,
 197                          unsigned int namelen)
 198 {
 199         enum dlm_status status;
 200         int o2dlm_mode = mode_to_o2dlm(mode);
 201         int o2dlm_flags = flags_to_o2dlm(flags);
 202         int ret;
 203
 204         status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
 205                          o2dlm_flags, name, namelen,
 206                          o2dlm_lock_ast_wrapper, lksb,
 207                          o2dlm_blocking_ast_wrapper);
 208         ret = dlm_status_to_errno(status);
 209         return ret;
 210 }
 211
 212 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
 213                            struct ocfs2_dlm_lksb *lksb,
 214                            u32 flags)
 215 {
 216         enum dlm_status status;
 217         int o2dlm_flags = flags_to_o2dlm(flags);
 218         int ret;
 219
 220         status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
 221                            o2dlm_flags, o2dlm_unlock_ast_wrapper, lksb);
 222         ret = dlm_status_to_errno(status);
 223         return ret;
 224 }
 225
 226 static int o2cb_dlm_lock_status(struct ocfs2_dlm_lksb *lksb)
 227 {
 228         return dlm_status_to_errno(lksb->lksb_o2dlm.status);
 229 }
 230
 231 /*
 232  * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB
 233  * contents, it will zero out the LVB.  Thus the caller can always trust
 234  * the contents.
 235  */
 236 static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
 237 {
 238         return 1;
 239 }
 240
 241 static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
 242 {
 243         return (void *)(lksb->lksb_o2dlm.lvb);
 244 }
 245
 246 static void o2cb_dump_lksb(struct ocfs2_dlm_lksb *lksb)
 247 {
 248         dlm_print_one_lock(lksb->lksb_o2dlm.lockid);
 249 }
 250
 251 /*
 252  * Check if this node is heartbeating and is connected to all other
 253  * heartbeating nodes.
 254  */
 255 static int o2cb_cluster_check(void)
 256 {
 257         u8 node_num;
 258         int i;
 259         unsigned long hbmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
 260         unsigned long netmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
 261
 262         node_num = o2nm_this_node();
 263         if (node_num == O2NM_MAX_NODES) {
 264                 printk(KERN_ERR "o2cb: This node has not been configured.\n");
 265                 return -EINVAL;
 266         }
 267
 268         /*
 269          * o2dlm expects o2net sockets to be created. If not, then
 270          * dlm_join_domain() fails with a stack of errors which are both cryptic
 271          * and incomplete. The idea here is to detect upfront whether we have
 272          * managed to connect to all nodes or not. If not, then list the nodes
 273          * to allow the user to check the configuration (incorrect IP, firewall,
 274          * etc.) Yes, this is racy. But its not the end of the world.
 275          */
 276 #define O2CB_MAP_STABILIZE_COUNT        60
 277         for (i = 0; i < O2CB_MAP_STABILIZE_COUNT; ++i) {
 278                 o2hb_fill_node_map(hbmap, sizeof(hbmap));
 279                 if (!test_bit(node_num, hbmap)) {
 280                         printk(KERN_ERR "o2cb: %s heartbeat has not been "
 281                                "started.\n", (o2hb_global_heartbeat_active() ?
 282                                               "Global" : "Local"));
 283                         return -EINVAL;
 284                 }
 285                 o2net_fill_node_map(netmap, sizeof(netmap));
 286                 /* Force set the current node to allow easy compare */
 287                 set_bit(node_num, netmap);
 288                 if (!memcmp(hbmap, netmap, sizeof(hbmap)))
 289                         return 0;
 290                 if (i < O2CB_MAP_STABILIZE_COUNT - 1)
 291                         msleep(1000);
 292         }
 293
 294         printk(KERN_ERR "o2cb: This node could not connect to nodes:");
 295         i = -1;
 296         while ((i = find_next_bit(hbmap, O2NM_MAX_NODES,
 297                                   i + 1)) < O2NM_MAX_NODES) {
 298                 if (!test_bit(i, netmap))
 299                         printk(" %u", i);
 300         }
 301         printk(".\n");
 302
 303         return -ENOTCONN;
 304 }
 305
 306 /*
 307  * Called from the dlm when it's about to evict a node. This is how the
 308  * classic stack signals node death.
 309  */
 310 static void o2dlm_eviction_cb(int node_num, void *data)
 311 {
 312         struct ocfs2_cluster_connection *conn = data;
 313
 314         printk(KERN_NOTICE "o2cb: o2dlm has evicted node %d from domain %.*s\n",
 315                node_num, conn->cc_namelen, conn->cc_name);
 316
 317         conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
 318 }
 319
 320 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
 321 {
 322         int rc = 0;
 323         u32 dlm_key;
 324         struct dlm_ctxt *dlm;
 325         struct o2dlm_private *priv;
 326         struct dlm_protocol_version fs_version;
 327
 328         BUG_ON(conn == NULL);
 329         BUG_ON(conn->cc_proto == NULL);
 330
 331         /* Ensure cluster stack is up and all nodes are connected */
 332         rc = o2cb_cluster_check();
 333         if (rc) {
 334                 printk(KERN_ERR "o2cb: Cluster check failed. Fix errors "
 335                        "before retrying.\n");
 336                 goto out;
 337         }
 338
 339         priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
 340         if (!priv) {
 341                 rc = -ENOMEM;
 342                 goto out_free;
 343         }
 344
 345         /* This just fills the structure in.  It is safe to pass conn. */
 346         dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
 347                               conn);
 348
 349         conn->cc_private = priv;
 350
 351         /* used by the dlm code to make message headers unique, each
 352          * node in this domain must agree on this. */
 353         dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen);
 354         fs_version.pv_major = conn->cc_version.pv_major;
 355         fs_version.pv_minor = conn->cc_version.pv_minor;
 356
 357         dlm = dlm_register_domain(conn->cc_name, dlm_key, &fs_version);
 358         if (IS_ERR(dlm)) {
 359                 rc = PTR_ERR(dlm);
 360                 mlog_errno(rc);
 361                 goto out_free;
 362         }
 363
 364         conn->cc_version.pv_major = fs_version.pv_major;
 365         conn->cc_version.pv_minor = fs_version.pv_minor;
 366         conn->cc_lockspace = dlm;
 367
 368         dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
 369
 370 out_free:
 371         if (rc)
 372                 kfree(conn->cc_private);
 373
 374 out:
 375         return rc;
 376 }
 377
 378 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn)
 379 {
 380         struct dlm_ctxt *dlm = conn->cc_lockspace;
 381         struct o2dlm_private *priv = conn->cc_private;
 382
 383         dlm_unregister_eviction_cb(&priv->op_eviction_cb);
 384         conn->cc_private = NULL;
 385         kfree(priv);
 386
 387         dlm_unregister_domain(dlm);
 388         conn->cc_lockspace = NULL;
 389
 390         return 0;
 391 }
 392
 393 static int o2cb_cluster_this_node(struct ocfs2_cluster_connection *conn,
 394                                   unsigned int *node)
 395 {
 396         int node_num;
 397
 398         node_num = o2nm_this_node();
 399         if (node_num == O2NM_INVALID_NODE_NUM)
 400                 return -ENOENT;
 401
 402         if (node_num >= O2NM_MAX_NODES)
 403                 return -EOVERFLOW;
 404
 405         *node = node_num;
 406         return 0;
 407 }
 408
 409 static struct ocfs2_stack_operations o2cb_stack_ops = {
 410         .connect        = o2cb_cluster_connect,
 411         .disconnect     = o2cb_cluster_disconnect,
 412         .this_node      = o2cb_cluster_this_node,
 413         .dlm_lock       = o2cb_dlm_lock,
 414         .dlm_unlock     = o2cb_dlm_unlock,
 415         .lock_status    = o2cb_dlm_lock_status,
 416         .lvb_valid      = o2cb_dlm_lvb_valid,
 417         .lock_lvb       = o2cb_dlm_lvb,
 418         .dump_lksb      = o2cb_dump_lksb,
 419 };
 420
 421 static struct ocfs2_stack_plugin o2cb_stack = {
 422         .sp_name        = "o2cb",
 423         .sp_ops         = &o2cb_stack_ops,
 424         .sp_owner       = THIS_MODULE,
 425 };
 426
 427 static int __init o2cb_stack_init(void)
 428 {
 429         return ocfs2_stack_glue_register(&o2cb_stack);
 430 }
 431
 432 static void __exit o2cb_stack_exit(void)
 433 {
 434         ocfs2_stack_glue_unregister(&o2cb_stack);
 435 }
 436
 437 MODULE_AUTHOR("Oracle");
 438 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack");
 439 MODULE_LICENSE("GPL");
 440 module_init(o2cb_stack_init);
 441 module_exit(o2cb_stack_exit);