lustre/obdclass/genops.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3 *
   4  *  linux/fs/ext2_obd/sim_obd.c
   5  * Copyright (C) 2001  Cluster File Systems, Inc.
   6  *
   7  * This code is issued under the GNU General Public License.
   8  * See the file COPYING in this distribution
   9  *
  10  * These are the only exported functions, they provide some generic
  11  * infrastructure for managing object devices
  12  *
  13  */
  14
  15 #define DEBUG_SUBSYSTEM S_CLASS
  16 #include <linux/kmod.h>   /* for request_module() */
  17 #include <linux/module.h>
  18 #include <linux/obd_class.h>
  19 #include <linux/random.h>
  20 #include <linux/slab.h>
  21
  22 extern struct list_head obd_types;
  23 extern struct obd_device obd_dev[MAX_OBD_DEVICES];
  24 kmem_cache_t *obdo_cachep = NULL;
  25 kmem_cache_t *export_cachep = NULL;
  26 kmem_cache_t *import_cachep = NULL;
  27
  28 /*
  29  * support functions: we could use inter-module communication, but this
  30  * is more portable to other OS's
  31  */
  32 static struct obd_type *class_search_type(char *nm)
  33 {
  34         struct list_head *tmp;
  35         struct obd_type *type;
  36         CDEBUG(D_INFO, "SEARCH %s\n", nm);
  37
  38         tmp = &obd_types;
  39         while ( (tmp = tmp->next) != &obd_types ) {
  40                 type = list_entry(tmp, struct obd_type, typ_chain);
  41                 CDEBUG(D_INFO, "TYP %s\n", type->typ_name);
  42                 if (strlen(type->typ_name) == strlen(nm) &&
  43                     strcmp(type->typ_name, nm) == 0 ) {
  44                         return type;
  45                 }
  46         }
  47         return NULL;
  48 }
  49
  50 struct obd_type *class_nm_to_type(char *nm)
  51 {
  52         struct obd_type *type = class_search_type(nm);
  53
  54 #ifdef CONFIG_KMOD
  55         if ( !type ) {
  56                 if ( !request_module(nm) ) {
  57                         CDEBUG(D_INFO, "Loaded module '%s'\n", nm);
  58                         type = class_search_type(nm);
  59                 } else {
  60                         CDEBUG(D_INFO, "Can't load module '%s'\n", nm);
  61                 }
  62         }
  63 #endif
  64         return type;
  65 }
  66
  67 int class_register_type(struct obd_ops *ops, char *nm)
  68 {
  69         struct obd_type *type;
  70
  71         ENTRY;
  72
  73         if (class_search_type(nm)) {
  74                 CDEBUG(D_IOCTL, "Type %s already registered\n", nm);
  75                 RETURN(-EEXIST);
  76         }
  77
  78         OBD_ALLOC(type, sizeof(*type));
  79         if (!type)
  80                 RETURN(-ENOMEM);
  81         INIT_LIST_HEAD(&type->typ_chain);
  82         MOD_INC_USE_COUNT;
  83         list_add(&type->typ_chain, obd_types.next);
  84         type->typ_ops = ops;
  85         type->typ_name = nm;
  86         RETURN(0);
  87 }
  88
  89 int class_unregister_type(char *nm)
  90 {
  91         struct obd_type *type = class_nm_to_type(nm);
  92
  93         ENTRY;
  94
  95         if ( !type ) {
  96                 CERROR("unknown obd type\n");
  97                 RETURN(-EINVAL);
  98         }
  99
 100         if ( type->typ_refcnt ) {
 101                 CERROR("type %s has refcount (%d)\n", nm, type->typ_refcnt);
 102                 RETURN(-EBUSY);
 103         }
 104
 105         list_del(&type->typ_chain);
 106         OBD_FREE(type, sizeof(*type));
 107         MOD_DEC_USE_COUNT;
 108         RETURN(0);
 109 } /* class_unregister_type */
 110
 111 int class_name2dev(char *name)
 112 {
 113         int res = -1;
 114         int i;
 115
 116         if (!name)
 117                 return -1;
 118
 119         for (i=0; i < MAX_OBD_DEVICES; i++) {
 120                 struct obd_device *obd = &obd_dev[i];
 121                 if (obd->obd_name && strcmp(name, obd->obd_name) == 0) {
 122                         res = i;
 123                         return res;
 124                 }
 125         }
 126
 127         return res;
 128 }
 129
 130 int class_uuid2dev(char *name)
 131 {
 132         int res = -1;
 133         int i;
 134
 135         for (i=0; i < MAX_OBD_DEVICES; i++) {
 136                 struct obd_device *obd = &obd_dev[i];
 137                 if (obd->obd_name && strncmp(name, obd->obd_uuid, 37) == 0) {
 138                         res = i;
 139                         return res;
 140                 }
 141         }
 142
 143         return res;
 144 }
 145
 146
 147 struct obd_device *class_uuid2obd(char *name)
 148 {
 149         int i;
 150
 151         for (i=0; i < MAX_OBD_DEVICES; i++) {
 152                 struct obd_device *obd = &obd_dev[i];
 153                 if (obd->obd_name && strncmp(name, obd->obd_uuid, 37) == 0) {
 154                         return obd;
 155                 }
 156         }
 157
 158         return NULL;
 159 }
 160
 161 void obd_cleanup_caches(void)
 162 {
 163         int rc;
 164         ENTRY;
 165         if (obdo_cachep) {
 166                 rc = kmem_cache_destroy(obdo_cachep);
 167                 if (rc)
 168                         CERROR("Cannot destory obdo_cachep\n");
 169                 obdo_cachep = NULL;
 170         }
 171         if (import_cachep) {
 172                 rc = kmem_cache_destroy(import_cachep);
 173                 if (rc)
 174                         CERROR("Cannot destory import_cachep\n");
 175                 import_cachep = NULL;
 176         }
 177         if (export_cachep) {
 178                 rc = kmem_cache_destroy(export_cachep);
 179                 if (rc)
 180                         CERROR("Cannot destory import_cachep\n");
 181                 export_cachep = NULL;
 182         }
 183         EXIT;
 184 }
 185
 186 int obd_init_caches(void)
 187 {
 188         ENTRY;
 189         if (obdo_cachep == NULL) {
 190                 obdo_cachep = kmem_cache_create("obdo_cache",
 191                                                 sizeof(struct obdo),
 192                                                 0, SLAB_HWCACHE_ALIGN,
 193                                                 NULL, NULL);
 194                 if (obdo_cachep == NULL)
 195                         GOTO(out, -ENOMEM);
 196         }
 197
 198         if (export_cachep == NULL) {
 199                 export_cachep = kmem_cache_create("export_cache",
 200                                                 sizeof(struct obd_export),
 201                                                 0, SLAB_HWCACHE_ALIGN,
 202                                                 NULL, NULL);
 203                 if (export_cachep == NULL)
 204                         GOTO(out, -ENOMEM);
 205         }
 206
 207         if (import_cachep == NULL) {
 208                 import_cachep = kmem_cache_create("import_cache",
 209                                                 sizeof(struct obd_import),
 210                                                 0, SLAB_HWCACHE_ALIGN,
 211                                                 NULL, NULL);
 212                 if (import_cachep == NULL)
 213                         GOTO(out, -ENOMEM);
 214         }
 215         RETURN(0);
 216  out:
 217         obd_cleanup_caches();
 218         RETURN(-ENOMEM);
 219
 220 }
 221
 222 /* map connection to client */
 223 struct obd_export *class_conn2export(struct lustre_handle *conn)
 224 {
 225         struct obd_export *export;
 226
 227         if (!conn) {
 228                 CDEBUG(D_CACHE, "looking for null handle\n");
 229                 RETURN(NULL);
 230         }
 231
 232         if (conn->addr == -1) {  /* this means assign a new connection */
 233                 CDEBUG(D_CACHE, "want a new connection\n");
 234                 RETURN(NULL);
 235         }
 236
 237         if (!conn->addr) {
 238                 CDEBUG(D_CACHE, "looking for null addr\n");
 239                 fixme();
 240                 RETURN(NULL);
 241         }
 242
 243         CDEBUG(D_IOCTL, "looking for export addr %Lx cookie %Lx\n",
 244                conn->addr, conn->cookie);
 245         export = (struct obd_export *) (unsigned long)conn->addr;
 246         if (!kmem_cache_validate(export_cachep, (void *)export))
 247                 RETURN(NULL);
 248
 249         if (export->exp_cookie != conn->cookie)
 250                 return NULL;
 251         return export;
 252 } /* class_conn2export */
 253
 254 struct obd_device *class_conn2obd(struct lustre_handle *conn)
 255 {
 256         struct obd_export *export;
 257         export = class_conn2export(conn);
 258         if (export)
 259                 return export->exp_obd;
 260         fixme();
 261         return NULL;
 262 }
 263
 264 /* a connection defines an export context in which preallocation can
 265    be managed. */
 266 int class_connect (struct lustre_handle *conn, struct obd_device *obd)
 267 {
 268         struct obd_export * export;
 269
 270         export = kmem_cache_alloc(export_cachep, GFP_KERNEL);
 271         if ( !export ) {
 272                 CERROR("no memory! (minor %d)\n", obd->obd_minor);
 273                 return -ENOMEM;
 274         }
 275
 276         memset(export, 0, sizeof(*export));
 277         get_random_bytes(&export->exp_cookie, sizeof(__u64));
 278         export->exp_obd = obd;
 279         export->exp_rconnh.addr = conn->addr;
 280         export->exp_rconnh.cookie = conn->cookie;
 281
 282         list_add(&(export->exp_chain), export->exp_obd->obd_exports.prev);
 283         conn->addr = (__u64) (unsigned long)export;
 284         conn->cookie = export->exp_cookie;
 285         CDEBUG(D_IOCTL, "connect: addr %Lx cookie %Lx\n",
 286                (long long)conn->addr, (long long)conn->cookie);
 287         return 0;
 288 }
 289
 290 int class_rconn2export(struct lustre_handle *conn, struct lustre_handle *rconn)
 291 {
 292         struct obd_export *export = class_conn2export(conn);
 293
 294         if (!export)
 295                 return -EINVAL;
 296
 297         export->exp_rconnh.addr = rconn->addr;
 298         export->exp_rconnh.cookie = rconn->cookie;
 299
 300         return 0;
 301 }
 302
 303 int class_disconnect(struct lustre_handle *conn)
 304 {
 305         struct obd_export *export;
 306         ENTRY;
 307
 308         if (!(export = class_conn2export(conn))) {
 309                 fixme();
 310                 CDEBUG(D_IOCTL, "disconnect: attempting to free "
 311                        "nonexistent client %Lx\n", conn->addr);
 312                 RETURN(-EINVAL);
 313         } else
 314                 CDEBUG(D_IOCTL, "disconnect: addr %Lx cookie %Lx\n",
 315                        (long long)conn->addr, (long long)conn->cookie);
 316         list_del(&export->exp_chain);
 317         kmem_cache_free(export_cachep, export);
 318
 319         RETURN(0);
 320 }
 321
 322 #if 0
 323
 324 /* FIXME: Data is a space- or comma-separated list of device IDs.  This will
 325  * have to change. */
 326 int class_multi_setup(struct obd_device *obddev, uint32_t len, void *data)
 327 {
 328         int count, rc;
 329         char *p;
 330         ENTRY;
 331
 332         for (p = data, count = 0; p < (char *)data + len; count++) {
 333                 char *end;
 334                 int tmp = simple_strtoul(p, &end, 0);
 335
 336                 if (p == end) {
 337                         CERROR("invalid device ID starting at: %s\n", p);
 338                         GOTO(err_disconnect, rc = -EINVAL);
 339                 }
 340
 341                 if (tmp < 0 || tmp >= MAX_OBD_DEVICES) {
 342                         CERROR("Trying to sub dev %d  - dev no too large\n",
 343                                tmp);
 344                         GOTO(err_disconnect, rc  = -EINVAL);
 345                 }
 346
 347                 rc = obd_connect(&obddev->obd_multi_conn[count], &obd_dev[tmp]);
 348                 if (rc) {
 349                         CERROR("cannot connect to device %d: rc = %d\n", tmp,
 350                                rc);
 351                         GOTO(err_disconnect, rc);
 352                 }
 353
 354                 CDEBUG(D_INFO, "target OBD %d is of type %s\n", count,
 355                        obd_dev[tmp].obd_type->typ_name);
 356
 357                 p = end + 1;
 358         }
 359
 360         obddev->obd_multi_count = count;
 361
 362         RETURN(0);
 363
 364  err_disconnect:
 365         for (count--; count >= 0; count--)
 366                 obd_disconnect(&obddev->obd_multi_conn[count]);
 367         return rc;
 368 }
 369
 370 /*
 371  *    remove all connections to this device
 372  *    close all connections to lower devices
 373  *    needed for forced unloads of OBD client drivers
 374  */
 375 int class_multi_cleanup(struct obd_device *obddev)
 376 {
 377         int i;
 378
 379         for (i = 0; i < obddev->obd_multi_count; i++) {
 380                 int rc;
 381                 struct obd_device *obd = class_conn2obd(&obddev->obd_multi_conn[i]);
 382
 383                 if (!obd) {
 384                         CERROR("no such device [i %d]\n", i);
 385                         RETURN(-EINVAL);
 386                 }
 387
 388                 rc = obd_disconnect(&obddev->obd_multi_conn[i]);
 389                 if (rc)
 390                         CERROR("disconnect failure %d\n", obd->obd_minor);
 391         }
 392         return 0;
 393 }
 394 #endif