fs/reiser4/plugin/cluster.c

   1 /* Copyright 2001, 2002, 2003 by Hans Reiser, licensing governed by
   2  * reiser4/README */
   3
   4 /* Contains reiser4 cluster plugins (see
   5    http://www.namesys.com/cryptcompress_design.html
   6    "Concepts of clustering" for details). */
   7
   8 #include "plugin_header.h"
   9 #include "plugin.h"
  10 #include "../inode.h"
  11
  12 static int change_cluster(struct inode *inode,
  13                           reiser4_plugin * plugin,
  14                           pset_member memb)
  15 {
  16         assert("edward-1324", inode != NULL);
  17         assert("edward-1325", plugin != NULL);
  18         assert("edward-1326", is_reiser4_inode(inode));
  19         assert("edward-1327", plugin->h.type_id == REISER4_CLUSTER_PLUGIN_TYPE);
  20
  21         /* Can't change the cluster plugin for already existent regular files */
  22         if (!plugin_of_group(inode_file_plugin(inode), REISER4_DIRECTORY_FILE))
  23                 return RETERR(-EINVAL);
  24
  25         /* If matches, nothing to change. */
  26         if (inode_hash_plugin(inode) != NULL &&
  27             inode_hash_plugin(inode)->h.id == plugin->h.id)
  28                 return 0;
  29
  30         return aset_set_unsafe(&reiser4_inode_data(inode)->pset,
  31                                PSET_CLUSTER, plugin);
  32 }
  33
  34 static reiser4_plugin_ops cluster_plugin_ops = {
  35         .init = NULL,
  36         .load = NULL,
  37         .save_len = NULL,
  38         .save = NULL,
  39         .change = &change_cluster
  40 };
  41
  42 #define SUPPORT_CLUSTER(SHIFT, ID, LABEL, DESC)                 \
  43         [CLUSTER_ ## ID ## _ID] = {                             \
  44                 .h = {                                          \
  45                         .type_id = REISER4_CLUSTER_PLUGIN_TYPE, \
  46                         .id = CLUSTER_ ## ID ## _ID,            \
  47                         .pops = &cluster_plugin_ops,            \
  48                         .label = LABEL,                         \
  49                         .desc = DESC,                           \
  50                         .linkage = {NULL, NULL}                 \
  51                 },                                              \
  52                 .shift = SHIFT                                  \
  53         }
  54
  55 cluster_plugin cluster_plugins[LAST_CLUSTER_ID] = {
  56         SUPPORT_CLUSTER(16, 64K, "64K", "Large"),
  57         SUPPORT_CLUSTER(15, 32K, "32K", "Big"),
  58         SUPPORT_CLUSTER(14, 16K, "16K", "Average"),
  59         SUPPORT_CLUSTER(13, 8K, "8K", "Small"),
  60         SUPPORT_CLUSTER(12, 4K, "4K", "Minimal")
  61 };
  62
  63 /*
  64   Local variables:
  65   c-indentation-style: "K&R"
  66   mode-name: "LC"
  67   c-basic-offset: 8
  68   tab-width: 8
  69   fill-column: 120
  70   scroll-step: 1
  71   End:
  72 */