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