linux/fs/ocfs2/stack_o2cb.c
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   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
  25struct o2dlm_private {
  26        struct dlm_eviction_cb op_eviction_cb;
  27};
  28
  29static 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
  53static inline int mode_to_o2dlm(int mode)
  54{
  55        BUG_ON(mode > LKM_MAXMODE);
  56
  57        return mode;
  58}
  59
  60static 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 */
 102static 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
 147static 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
 154static 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
 161static 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
 168static 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
 190static 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
 210static 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
 224static 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 */
 234static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
 235{
 236        return 1;
 237}
 238
 239static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
 240{
 241        return (void *)(lksb->lksb_o2dlm.lvb);
 242}
 243
 244static 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 */
 253static 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, sizeof(hbmap));
 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, sizeof(netmap));
 284                /* Force set the current node to allow easy compare */
 285                set_bit(node_num, netmap);
 286                if (!memcmp(hbmap, netmap, sizeof(hbmap)))
 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 */
 308static 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
 318static 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
 368out_free:
 369        if (rc)
 370                kfree(conn->cc_private);
 371
 372out:
 373        return rc;
 374}
 375
 376static 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
 391static 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
 407static 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
 419static struct ocfs2_stack_plugin o2cb_stack = {
 420        .sp_name        = "o2cb",
 421        .sp_ops         = &o2cb_stack_ops,
 422        .sp_owner       = THIS_MODULE,
 423};
 424
 425static int __init o2cb_stack_init(void)
 426{
 427        return ocfs2_stack_glue_register(&o2cb_stack);
 428}
 429
 430static void __exit o2cb_stack_exit(void)
 431{
 432        ocfs2_stack_glue_unregister(&o2cb_stack);
 433}
 434
 435MODULE_AUTHOR("Oracle");
 436MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack");
 437MODULE_LICENSE("GPL");
 438module_init(o2cb_stack_init);
 439module_exit(o2cb_stack_exit);
 440