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