SAFE public projects git trees. - safe/jmp/linux-2.6/blob - fs/dlm/debug_fs.c

   1 /******************************************************************************
   2 *******************************************************************************
   3 **
   4 **  Copyright (C) 2005 Red Hat, Inc.  All rights reserved.
   5 **
   6 **  This copyrighted material is made available to anyone wishing to use,
   7 **  modify, copy, or redistribute it subject to the terms and conditions
   8 **  of the GNU General Public License v.2.
   9 **
  10 *******************************************************************************
  11 ******************************************************************************/
  12
  13 #include <linux/pagemap.h>
  14 #include <linux/seq_file.h>
  15 #include <linux/module.h>
  16 #include <linux/ctype.h>
  17 #include <linux/debugfs.h>
  18
  19 #include "dlm_internal.h"
  20
  21
  22 static struct dentry *dlm_root;
  23
  24 struct rsb_iter {
  25         int entry;
  26         struct dlm_ls *ls;
  27         struct list_head *next;
  28         struct dlm_rsb *rsb;
  29 };
  30
  31 static char *print_lockmode(int mode)
  32 {
  33         switch (mode) {
  34         case DLM_LOCK_IV:
  35                 return "--";
  36         case DLM_LOCK_NL:
  37                 return "NL";
  38         case DLM_LOCK_CR:
  39                 return "CR";
  40         case DLM_LOCK_CW:
  41                 return "CW";
  42         case DLM_LOCK_PR:
  43                 return "PR";
  44         case DLM_LOCK_PW:
  45                 return "PW";
  46         case DLM_LOCK_EX:
  47                 return "EX";
  48         default:
  49                 return "??";
  50         }
  51 }
  52
  53 static void print_lock(struct seq_file *s, struct dlm_lkb *lkb,
  54                        struct dlm_rsb *res)
  55 {
  56         seq_printf(s, "%08x %s", lkb->lkb_id, print_lockmode(lkb->lkb_grmode));
  57
  58         if (lkb->lkb_status == DLM_LKSTS_CONVERT
  59             || lkb->lkb_status == DLM_LKSTS_WAITING)
  60                 seq_printf(s, " (%s)", print_lockmode(lkb->lkb_rqmode));
  61
  62         if (lkb->lkb_range) {
  63                 /* FIXME: this warns on Alpha */
  64                 if (lkb->lkb_status == DLM_LKSTS_CONVERT
  65                     || lkb->lkb_status == DLM_LKSTS_GRANTED)
  66                         seq_printf(s, " %" PRIx64 "-%" PRIx64,
  67                                    lkb->lkb_range[GR_RANGE_START],
  68                                    lkb->lkb_range[GR_RANGE_END]);
  69                 if (lkb->lkb_status == DLM_LKSTS_CONVERT
  70                     || lkb->lkb_status == DLM_LKSTS_WAITING)
  71                         seq_printf(s, " (%" PRIx64 "-%" PRIx64 ")",
  72                                    lkb->lkb_range[RQ_RANGE_START],
  73                                    lkb->lkb_range[RQ_RANGE_END]);
  74         }
  75
  76         if (lkb->lkb_nodeid) {
  77                 if (lkb->lkb_nodeid != res->res_nodeid)
  78                         seq_printf(s, " Remote: %3d %08x", lkb->lkb_nodeid,
  79                                    lkb->lkb_remid);
  80                 else
  81                         seq_printf(s, " Master:     %08x", lkb->lkb_remid);
  82         }
  83
  84         if (lkb->lkb_wait_type)
  85                 seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
  86
  87         seq_printf(s, "\n");
  88 }
  89
  90 static int print_resource(struct dlm_rsb *res, struct seq_file *s)
  91 {
  92         struct dlm_lkb *lkb;
  93         int i, lvblen = res->res_ls->ls_lvblen;
  94
  95         seq_printf(s, "\nResource %p Name (len=%d) \"", res, res->res_length);
  96         for (i = 0; i < res->res_length; i++) {
  97                 if (isprint(res->res_name[i]))
  98                         seq_printf(s, "%c", res->res_name[i]);
  99                 else
 100                         seq_printf(s, "%c", '.');
 101         }
 102         if (res->res_nodeid > 0)
 103                 seq_printf(s, "\"  \nLocal Copy, Master is node %d\n",
 104                            res->res_nodeid);
 105         else if (res->res_nodeid == 0)
 106                 seq_printf(s, "\"  \nMaster Copy\n");
 107         else if (res->res_nodeid == -1)
 108                 seq_printf(s, "\"  \nLooking up master (lkid %x)\n",
 109                            res->res_first_lkid);
 110         else
 111                 seq_printf(s, "\"  \nInvalid master %d\n", res->res_nodeid);
 112
 113         /* Print the LVB: */
 114         if (res->res_lvbptr) {
 115                 seq_printf(s, "LVB: ");
 116                 for (i = 0; i < lvblen; i++) {
 117                         if (i == lvblen / 2)
 118                                 seq_printf(s, "\n     ");
 119                         seq_printf(s, "%02x ",
 120                                    (unsigned char) res->res_lvbptr[i]);
 121                 }
 122                 if (rsb_flag(res, RSB_VALNOTVALID))
 123                         seq_printf(s, " (INVALID)");
 124                 seq_printf(s, "\n");
 125         }
 126
 127         /* Print the locks attached to this resource */
 128         seq_printf(s, "Granted Queue\n");
 129         list_for_each_entry(lkb, &res->res_grantqueue, lkb_statequeue)
 130                 print_lock(s, lkb, res);
 131
 132         seq_printf(s, "Conversion Queue\n");
 133         list_for_each_entry(lkb, &res->res_convertqueue, lkb_statequeue)
 134                 print_lock(s, lkb, res);
 135
 136         seq_printf(s, "Waiting Queue\n");
 137         list_for_each_entry(lkb, &res->res_waitqueue, lkb_statequeue)
 138                 print_lock(s, lkb, res);
 139
 140         return 0;
 141 }
 142
 143 static int rsb_iter_next(struct rsb_iter *ri)
 144 {
 145         struct dlm_ls *ls = ri->ls;
 146         int i;
 147
 148         if (!ri->next) {
 149  top:
 150                 /* Find the next non-empty hash bucket */
 151                 for (i = ri->entry; i < ls->ls_rsbtbl_size; i++) {
 152                         read_lock(&ls->ls_rsbtbl[i].lock);
 153                         if (!list_empty(&ls->ls_rsbtbl[i].list)) {
 154                                 ri->next = ls->ls_rsbtbl[i].list.next;
 155                                 read_unlock(&ls->ls_rsbtbl[i].lock);
 156                                 break;
 157                         }
 158                         read_unlock(&ls->ls_rsbtbl[i].lock);
 159                 }
 160                 ri->entry = i;
 161
 162                 if (ri->entry >= ls->ls_rsbtbl_size)
 163                         return 1;
 164         } else {
 165                 i = ri->entry;
 166                 read_lock(&ls->ls_rsbtbl[i].lock);
 167                 ri->next = ri->next->next;
 168                 if (ri->next->next == ls->ls_rsbtbl[i].list.next) {
 169                         /* End of list - move to next bucket */
 170                         ri->next = NULL;
 171                         ri->entry++;
 172                         read_unlock(&ls->ls_rsbtbl[i].lock);
 173                         goto top;
 174                 }
 175                 read_unlock(&ls->ls_rsbtbl[i].lock);
 176         }
 177         ri->rsb = list_entry(ri->next, struct dlm_rsb, res_hashchain);
 178
 179         return 0;
 180 }
 181
 182 static void rsb_iter_free(struct rsb_iter *ri)
 183 {
 184         kfree(ri);
 185 }
 186
 187 static struct rsb_iter *rsb_iter_init(struct dlm_ls *ls)
 188 {
 189         struct rsb_iter *ri;
 190
 191         ri = kmalloc(sizeof *ri, GFP_KERNEL);
 192         if (!ri)
 193                 return NULL;
 194
 195         ri->ls = ls;
 196         ri->entry = 0;
 197         ri->next = NULL;
 198
 199         if (rsb_iter_next(ri)) {
 200                 rsb_iter_free(ri);
 201                 return NULL;
 202         }
 203
 204         return ri;
 205 }
 206
 207 static void *seq_start(struct seq_file *file, loff_t *pos)
 208 {
 209         struct rsb_iter *ri;
 210         loff_t n = *pos;
 211
 212         ri = rsb_iter_init(file->private);
 213         if (!ri)
 214                 return NULL;
 215
 216         while (n--) {
 217                 if (rsb_iter_next(ri)) {
 218                         rsb_iter_free(ri);
 219                         return NULL;
 220                 }
 221         }
 222
 223         return ri;
 224 }
 225
 226 static void *seq_next(struct seq_file *file, void *iter_ptr, loff_t *pos)
 227 {
 228         struct rsb_iter *ri = iter_ptr;
 229
 230         (*pos)++;
 231
 232         if (rsb_iter_next(ri)) {
 233                 rsb_iter_free(ri);
 234                 return NULL;
 235         }
 236
 237         return ri;
 238 }
 239
 240 static void seq_stop(struct seq_file *file, void *iter_ptr)
 241 {
 242         /* nothing for now */
 243 }
 244
 245 static int seq_show(struct seq_file *file, void *iter_ptr)
 246 {
 247         struct rsb_iter *ri = iter_ptr;
 248
 249         print_resource(ri->rsb, file);
 250
 251         return 0;
 252 }
 253
 254 static struct seq_operations dlm_seq_ops = {
 255         .start = seq_start,
 256         .next  = seq_next,
 257         .stop  = seq_stop,
 258         .show  = seq_show,
 259 };
 260
 261 static int do_open(struct inode *inode, struct file *file)
 262 {
 263         struct seq_file *seq;
 264         int ret;
 265
 266         ret = seq_open(file, &dlm_seq_ops);
 267         if (ret)
 268                 return ret;
 269
 270         seq = file->private_data;
 271         seq->private = inode->u.generic_ip;
 272
 273         return 0;
 274 }
 275
 276 static struct file_operations dlm_fops = {
 277         .owner   = THIS_MODULE,
 278         .open    = do_open,
 279         .read    = seq_read,
 280         .llseek  = seq_lseek,
 281         .release = seq_release
 282 };
 283
 284 int dlm_create_debug_file(struct dlm_ls *ls)
 285 {
 286         ls->ls_debug_dentry = debugfs_create_file(ls->ls_name,
 287                                                   S_IFREG | S_IRUGO,
 288                                                   dlm_root,
 289                                                   ls,
 290                                                   &dlm_fops);
 291         return ls->ls_debug_dentry ? 0 : -ENOMEM;
 292 }
 293
 294 void dlm_delete_debug_file(struct dlm_ls *ls)
 295 {
 296         if (ls->ls_debug_dentry)
 297                 debugfs_remove(ls->ls_debug_dentry);
 298 }
 299
 300 int dlm_register_debugfs(void)
 301 {
 302         dlm_root = debugfs_create_dir("dlm", NULL);
 303         return dlm_root ? 0 : -ENOMEM;
 304 }
 305
 306 void dlm_unregister_debugfs(void)
 307 {
 308         debugfs_remove(dlm_root);
 309 }
 310