lustre/obdclass/genops.c

   1 /*
   2  *  linux/fs/ext2_obd/sim_obd.c
   3  * Copyright (C) 2001  Cluster File Systems, Inc.
   4  *
   5  * This code is issued under the GNU General Public License.
   6  * See the file COPYING in this distribution
   7  *
   8  * These are the only exported functions, they provide some generic
   9  * infrastructure for managing object devices
  10  *
  11  */
  12
  13 #define DEBUG_SUBSYSTEM S_CLASS
  14 #include <linux/kmod.h>   /* for request_module() */
  15 #include <linux/module.h>
  16 #include <linux/obd_class.h>
  17 #include <linux/random.h>
  18 #include <linux/slab.h>
  19
  20 extern struct list_head obd_types;
  21 extern struct obd_device obd_dev[MAX_OBD_DEVICES];
  22 kmem_cache_t *obdo_cachep = NULL;
  23 kmem_cache_t *export_cachep = NULL;
  24 kmem_cache_t *import_cachep = NULL;
  25
  26 /*
  27  * support functions: we could use inter-module communication, but this
  28  * is more portable to other OS's
  29  */
  30 static struct obd_type *class_search_type(char *nm)
  31 {
  32         struct list_head *tmp;
  33         struct obd_type *type;
  34         CDEBUG(D_INFO, "SEARCH %s\n", nm);
  35
  36         tmp = &obd_types;
  37         while ( (tmp = tmp->next) != &obd_types ) {
  38                 type = list_entry(tmp, struct obd_type, typ_chain);
  39                 CDEBUG(D_INFO, "TYP %s\n", type->typ_name);
  40                 if (strlen(type->typ_name) == strlen(nm) &&
  41                     strcmp(type->typ_name, nm) == 0 ) {
  42                         return type;
  43                 }
  44         }
  45         return NULL;
  46 }
  47
  48 struct obd_type *class_nm_to_type(char *nm)
  49 {
  50         struct obd_type *type = class_search_type(nm);
  51
  52 #ifdef CONFIG_KMOD
  53         if ( !type ) {
  54                 if ( !request_module(nm) ) {
  55                         CDEBUG(D_INFO, "Loaded module '%s'\n", nm);
  56                         type = class_search_type(nm);
  57                 } else {
  58                         CDEBUG(D_INFO, "Can't load module '%s'\n", nm);
  59                 }
  60         }
  61 #endif
  62         return type;
  63 }
  64
  65 int class_register_type(struct obd_ops *ops, char *nm)
  66 {
  67         struct obd_type *type;
  68
  69         ENTRY;
  70
  71         if (class_nm_to_type(nm)) {
  72                 CDEBUG(D_IOCTL, "Type %s already registered\n", nm);
  73                 RETURN(-EEXIST);
  74         }
  75
  76         OBD_ALLOC(type, sizeof(*type));
  77         if (!type)
  78                 RETURN(-ENOMEM);
  79         INIT_LIST_HEAD(&type->typ_chain);
  80         MOD_INC_USE_COUNT;
  81         list_add(&type->typ_chain, obd_types.next);
  82         type->typ_ops = ops;
  83         type->typ_name = nm;
  84         RETURN(0);
  85 }
  86
  87 int class_unregister_type(char *nm)
  88 {
  89         struct obd_type *type = class_nm_to_type(nm);
  90
  91         ENTRY;
  92
  93         if ( !type ) {
  94                 MOD_DEC_USE_COUNT;
  95                 CERROR("unknown obd type\n");
  96                 RETURN(-EINVAL);
  97         }
  98
  99         if ( type->typ_refcnt ) {
 100                 MOD_DEC_USE_COUNT;
 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                 RETURN(NULL);
 229
 230         if (!conn->addr || conn->addr == -1 ) {
 231                 fixme();
 232                 RETURN(NULL);
 233         }
 234
 235         export = (struct obd_export *) (unsigned long)conn->addr;
 236         if (!kmem_cache_validate(export_cachep, (void *)export))
 237                 RETURN(NULL);
 238
 239         if (export->export_cookie != conn->cookie)
 240                 return NULL;
 241         return export;
 242 } /* class_conn2export */
 243
 244 struct obd_device *class_conn2obd(struct lustre_handle *conn)
 245 {
 246         struct obd_export *export;
 247         export = class_conn2export(conn);
 248         if (export)
 249                 return export->export_obd;
 250         fixme();
 251         return NULL;
 252 }
 253
 254 /* a connection defines an export context in which preallocation can
 255    be managed. */
 256 int class_connect (struct lustre_handle *conn, struct obd_device *obd)
 257 {
 258         struct obd_export * export;
 259
 260         export = kmem_cache_alloc(export_cachep, GFP_KERNEL);
 261         if ( !export ) {
 262                 CERROR("no memory! (minor %d)\n", obd->obd_minor);
 263                 return -ENOMEM;
 264         }
 265
 266         memset(export, 0, sizeof(*export));
 267         get_random_bytes(&export->export_cookie, sizeof(__u64));
 268         export->export_obd = obd;
 269         export->export_import.addr = conn->addr;
 270         export->export_import.cookie = conn->cookie;
 271
 272         list_add(&(export->export_chain), export->export_obd->obd_exports.prev);
 273         conn->addr = (__u64) (unsigned long)export;
 274         conn->cookie = export->export_cookie;
 275         return 0;
 276 }
 277
 278 int class_disconnect(struct lustre_handle *conn)
 279 {
 280         struct obd_export * export;
 281         ENTRY;
 282
 283         if (!(export = class_conn2export(conn))) {
 284                 fixme();
 285                 CDEBUG(D_IOCTL, "disconnect: attempting to free "
 286                        "nonexistent client %Lx\n", conn->addr);
 287                 RETURN(-EINVAL);
 288         }
 289         list_del(&export->export_chain);
 290         kmem_cache_free(export_cachep, export);
 291
 292         RETURN(0);
 293 }
 294
 295 #if 0
 296
 297 /* FIXME: Data is a space- or comma-separated list of device IDs.  This will
 298  * have to change. */
 299 int class_multi_setup(struct obd_device *obddev, uint32_t len, void *data)
 300 {
 301         int count, rc;
 302         char *p;
 303         ENTRY;
 304
 305         for (p = data, count = 0; p < (char *)data + len; count++) {
 306                 char *end;
 307                 int tmp = simple_strtoul(p, &end, 0);
 308
 309                 if (p == end) {
 310                         CERROR("invalid device ID starting at: %s\n", p);
 311                         GOTO(err_disconnect, rc = -EINVAL);
 312                 }
 313
 314                 if (tmp < 0 || tmp >= MAX_OBD_DEVICES) {
 315                         CERROR("Trying to sub dev %d  - dev no too large\n",
 316                                tmp);
 317                         GOTO(err_disconnect, rc  = -EINVAL);
 318                 }
 319
 320                 rc = obd_connect(&obddev->obd_multi_conn[count], &obd_dev[tmp]);
 321                 if (rc) {
 322                         CERROR("cannot connect to device %d: rc = %d\n", tmp,
 323                                rc);
 324                         GOTO(err_disconnect, rc);
 325                 }
 326
 327                 CDEBUG(D_INFO, "target OBD %d is of type %s\n", count,
 328                        obd_dev[tmp].obd_type->typ_name);
 329
 330                 p = end + 1;
 331         }
 332
 333         obddev->obd_multi_count = count;
 334
 335         RETURN(0);
 336
 337  err_disconnect:
 338         for (count--; count >= 0; count--)
 339                 obd_disconnect(&obddev->obd_multi_conn[count]);
 340         return rc;
 341 }
 342
 343 /*
 344  *    remove all connections to this device
 345  *    close all connections to lower devices
 346  *    needed for forced unloads of OBD client drivers
 347  */
 348 int class_multi_cleanup(struct obd_device *obddev)
 349 {
 350         int i;
 351
 352         for (i = 0; i < obddev->obd_multi_count; i++) {
 353                 int rc;
 354                 struct obd_device *obd = class_conn2obd(&obddev->obd_multi_conn[i]);
 355
 356                 if (!obd) {
 357                         CERROR("no such device [i %d]\n", i);
 358                         RETURN(-EINVAL);
 359                 }
 360
 361                 rc = obd_disconnect(&obddev->obd_multi_conn[i]);
 362                 if (rc)
 363                         CERROR("disconnect failure %d\n", obd->obd_minor);
 364         }
 365         return 0;
 366 }
 367 #endif