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_search_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                 CERROR("unknown obd type\n");
  95                 RETURN(-EINVAL);
  96         }
  97
  98         if ( type->typ_refcnt ) {
  99                 CERROR("type %s has refcount (%d)\n", nm, type->typ_refcnt);
 100                 RETURN(-EBUSY);
 101         }
 102
 103         list_del(&type->typ_chain);
 104         OBD_FREE(type, sizeof(*type));
 105         MOD_DEC_USE_COUNT;
 106         RETURN(0);
 107 } /* class_unregister_type */
 108
 109 int class_name2dev(char *name)
 110 {
 111         int res = -1;
 112         int i;
 113
 114         if (!name)
 115             return -1;
 116
 117         for (i=0; i < MAX_OBD_DEVICES; i++) {
 118                 struct obd_device *obd = &obd_dev[i];
 119                 if (obd->obd_name && strcmp(name, obd->obd_name) == 0) {
 120                         res = i;
 121                         return res;
 122                 }
 123         }
 124
 125         return res;
 126 }
 127
 128 int class_uuid2dev(char *name)
 129 {
 130         int res = -1;
 131         int i;
 132
 133         for (i=0; i < MAX_OBD_DEVICES; i++) {
 134                 struct obd_device *obd = &obd_dev[i];
 135                 if (obd->obd_name && strncmp(name, obd->obd_uuid, 37) == 0) {
 136                         res = i;
 137                         return res;
 138                 }
 139         }
 140
 141         return res;
 142 }
 143
 144
 145 struct obd_device *class_uuid2obd(char *name)
 146 {
 147         int i;
 148
 149         for (i=0; i < MAX_OBD_DEVICES; i++) {
 150                 struct obd_device *obd = &obd_dev[i];
 151                 if (obd->obd_name && strncmp(name, obd->obd_uuid, 37) == 0) {
 152                         return obd;
 153                 }
 154         }
 155
 156         return NULL;
 157 }
 158
 159 void obd_cleanup_caches(void)
 160 {
 161         int rc;
 162         ENTRY;
 163         if (obdo_cachep) {
 164                 rc = kmem_cache_destroy(obdo_cachep);
 165                 if (rc)
 166                         CERROR("Cannot destory obdo_cachep\n");
 167                 obdo_cachep = NULL;
 168         }
 169         if (import_cachep) {
 170                 rc = kmem_cache_destroy(import_cachep);
 171                 if (rc)
 172                         CERROR("Cannot destory import_cachep\n");
 173                 import_cachep = NULL;
 174         }
 175         if (export_cachep) {
 176                 rc = kmem_cache_destroy(export_cachep);
 177                 if (rc)
 178                         CERROR("Cannot destory import_cachep\n");
 179                 export_cachep = NULL;
 180         }
 181         EXIT;
 182 }
 183
 184 int obd_init_caches(void)
 185 {
 186         ENTRY;
 187         if (obdo_cachep == NULL) {
 188                 obdo_cachep = kmem_cache_create("obdo_cache",
 189                                                 sizeof(struct obdo),
 190                                                 0, SLAB_HWCACHE_ALIGN,
 191                                                 NULL, NULL);
 192                 if (obdo_cachep == NULL)
 193                         GOTO(out, -ENOMEM);
 194         }
 195
 196         if (export_cachep == NULL) {
 197                 export_cachep = kmem_cache_create("export_cache",
 198                                                 sizeof(struct obd_export),
 199                                                 0, SLAB_HWCACHE_ALIGN,
 200                                                 NULL, NULL);
 201                 if (export_cachep == NULL)
 202                         GOTO(out, -ENOMEM);
 203         }
 204
 205         if (import_cachep == NULL) {
 206                 import_cachep = kmem_cache_create("import_cache",
 207                                                 sizeof(struct obd_import),
 208                                                 0, SLAB_HWCACHE_ALIGN,
 209                                                 NULL, NULL);
 210                 if (import_cachep == NULL)
 211                         GOTO(out, -ENOMEM);
 212         }
 213         RETURN(0);
 214  out:
 215         obd_cleanup_caches();
 216         RETURN(-ENOMEM);
 217
 218 }
 219
 220 /* map connection to client */
 221 struct obd_export *class_conn2export(struct lustre_handle *conn)
 222 {
 223         struct obd_export * export;
 224
 225         if (!conn)
 226                 RETURN(NULL);
 227
 228         if (!conn->addr || conn->addr == -1 ) {
 229                 fixme();
 230                 RETURN(NULL);
 231         }
 232
 233         export = (struct obd_export *) (unsigned long)conn->addr;
 234         if (!kmem_cache_validate(export_cachep, (void *)export))
 235                 RETURN(NULL);
 236
 237         if (export->export_cookie != conn->cookie)
 238                 return NULL;
 239         return export;
 240 } /* class_conn2export */
 241
 242 struct obd_device *class_conn2obd(struct lustre_handle *conn)
 243 {
 244         struct obd_export *export;
 245         export = class_conn2export(conn);
 246         if (export)
 247                 return export->export_obd;
 248         fixme();
 249         return NULL;
 250 }
 251
 252 /* a connection defines an export context in which preallocation can
 253    be managed. */
 254 int class_connect (struct lustre_handle *conn, struct obd_device *obd)
 255 {
 256         struct obd_export * export;
 257
 258         export = kmem_cache_alloc(export_cachep, GFP_KERNEL);
 259         if ( !export ) {
 260                 CERROR("no memory! (minor %d)\n", obd->obd_minor);
 261                 return -ENOMEM;
 262         }
 263
 264         memset(export, 0, sizeof(*export));
 265         get_random_bytes(&export->export_cookie, sizeof(__u64));
 266         export->export_obd = obd;
 267         export->export_import.addr = conn->addr;
 268         export->export_import.cookie = conn->cookie;
 269
 270         list_add(&(export->export_chain), export->export_obd->obd_exports.prev);
 271         conn->addr = (__u64) (unsigned long)export;
 272         conn->cookie = export->export_cookie;
 273         return 0;
 274 }
 275
 276 int class_disconnect(struct lustre_handle *conn)
 277 {
 278         struct obd_export * export;
 279         ENTRY;
 280
 281         if (!(export = class_conn2export(conn))) {
 282                 fixme();
 283                 CDEBUG(D_IOCTL, "disconnect: attempting to free "
 284                        "nonexistent client %Lx\n", conn->addr);
 285                 RETURN(-EINVAL);
 286         }
 287         list_del(&export->export_chain);
 288         kmem_cache_free(export_cachep, export);
 289
 290         RETURN(0);
 291 }
 292
 293 #if 0
 294
 295 /* FIXME: Data is a space- or comma-separated list of device IDs.  This will
 296  * have to change. */
 297 int class_multi_setup(struct obd_device *obddev, uint32_t len, void *data)
 298 {
 299         int count, rc;
 300         char *p;
 301         ENTRY;
 302
 303         for (p = data, count = 0; p < (char *)data + len; count++) {
 304                 char *end;
 305                 int tmp = simple_strtoul(p, &end, 0);
 306
 307                 if (p == end) {
 308                         CERROR("invalid device ID starting at: %s\n", p);
 309                         GOTO(err_disconnect, rc = -EINVAL);
 310                 }
 311
 312                 if (tmp < 0 || tmp >= MAX_OBD_DEVICES) {
 313                         CERROR("Trying to sub dev %d  - dev no too large\n",
 314                                tmp);
 315                         GOTO(err_disconnect, rc  = -EINVAL);
 316                 }
 317
 318                 rc = obd_connect(&obddev->obd_multi_conn[count], &obd_dev[tmp]);
 319                 if (rc) {
 320                         CERROR("cannot connect to device %d: rc = %d\n", tmp,
 321                                rc);
 322                         GOTO(err_disconnect, rc);
 323                 }
 324
 325                 CDEBUG(D_INFO, "target OBD %d is of type %s\n", count,
 326                        obd_dev[tmp].obd_type->typ_name);
 327
 328                 p = end + 1;
 329         }
 330
 331         obddev->obd_multi_count = count;
 332
 333         RETURN(0);
 334
 335  err_disconnect:
 336         for (count--; count >= 0; count--)
 337                 obd_disconnect(&obddev->obd_multi_conn[count]);
 338         return rc;
 339 }
 340
 341 /*
 342  *    remove all connections to this device
 343  *    close all connections to lower devices
 344  *    needed for forced unloads of OBD client drivers
 345  */
 346 int class_multi_cleanup(struct obd_device *obddev)
 347 {
 348         int i;
 349
 350         for (i = 0; i < obddev->obd_multi_count; i++) {
 351                 int rc;
 352                 struct obd_device *obd = class_conn2obd(&obddev->obd_multi_conn[i]);
 353
 354                 if (!obd) {
 355                         CERROR("no such device [i %d]\n", i);
 356                         RETURN(-EINVAL);
 357                 }
 358
 359                 rc = obd_disconnect(&obddev->obd_multi_conn[i]);
 360                 if (rc)
 361                         CERROR("disconnect failure %d\n", obd->obd_minor);
 362         }
 363         return 0;
 364 }
 365 #endif