src/patches/suse-2.6.27.25/patches.fixes/dlm-allow-multiple-lockspaces.patch

   1 From: David Teigland <teigland@redhat.com>
   2 Subject: [PATCH] dlm: allow multiple lockspace creates
   3 Patch-mainline: 2.6.28?
   4 References: FATE110294
   5
   6 Add a count for lockspace create and release so that create can
   7 be called multiple times to use the lockspace from different places.
   8 Also add the new flag DLM_LSFL_NEWEXCL to create a lockspace with
   9 the previous behavior of returning -EEXIST if the lockspace already
  10 exists.
  11
  12 Signed-off-by: David Teigland <teigland@redhat.com>
  13 Acked-by: Mark Fasheh <mfasheh@suse.com>
  14 ---
  15  fs/dlm/dlm_internal.h       |    6 ++-
  16  fs/dlm/lockspace.c          |  107 ++++++++++++++++++++++++++++---------------
  17  fs/dlm/user.c               |   54 +++++++++++++--------
  18  fs/dlm/user.h               |    3 +-
  19  fs/gfs2/locking/dlm/mount.c |    3 +-
  20  include/linux/dlm.h         |    5 ++-
  21  include/linux/dlm_device.h  |    2 +-
  22  7 files changed, 116 insertions(+), 64 deletions(-)
  23
  24 diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
  25 index 5a7ac33..9e0622a 100644
  26 --- a/fs/dlm/dlm_internal.h
  27 +++ b/fs/dlm/dlm_internal.h
  28 @@ -2,7 +2,7 @@
  29  *******************************************************************************
  30  **
  31  **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
  32 -**  Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
  33 +**  Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
  34  **
  35  **  This copyrighted material is made available to anyone wishing to use,
  36  **  modify, copy, or redistribute it subject to the terms and conditions
  37 @@ -441,7 +441,9 @@ struct dlm_ls {
  38         uint32_t                ls_global_id;   /* global unique lockspace ID */
  39         uint32_t                ls_exflags;
  40         int                     ls_lvblen;
  41 -       int                     ls_count;       /* reference count */
  42 +       int                     ls_count;       /* refcount of processes in
  43 +                                                  the dlm using this ls */
  44 +       int                     ls_create_count; /* create/release refcount */
  45         unsigned long           ls_flags;       /* LSFL_ */
  46         struct kobject          ls_kobj;
  47
  48 diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
  49 index 499e167..56eae4e 100644
  50 --- a/fs/dlm/lockspace.c
  51 +++ b/fs/dlm/lockspace.c
  52 @@ -2,7 +2,7 @@
  53  *******************************************************************************
  54  **
  55  **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
  56 -**  Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
  57 +**  Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
  58  **
  59  **  This copyrighted material is made available to anyone wishing to use,
  60  **  modify, copy, or redistribute it subject to the terms and conditions
  61 @@ -23,6 +23,7 @@
  62  #include "lock.h"
  63  #include "recover.h"
  64  #include "requestqueue.h"
  65 +#include "user.h"
  66
  67  static int                     ls_count;
  68  static struct mutex            ls_lock;
  69 @@ -246,23 +247,6 @@ static void dlm_scand_stop(void)
  70         kthread_stop(scand_task);
  71  }
  72
  73 -static struct dlm_ls *dlm_find_lockspace_name(char *name, int namelen)
  74 -{
  75 -       struct dlm_ls *ls;
  76 -
  77 -       spin_lock(&lslist_lock);
  78 -
  79 -       list_for_each_entry(ls, &lslist, ls_list) {
  80 -               if (ls->ls_namelen == namelen &&
  81 -                   memcmp(ls->ls_name, name, namelen) == 0)
  82 -                       goto out;
  83 -       }
  84 -       ls = NULL;
  85 - out:
  86 -       spin_unlock(&lslist_lock);
  87 -       return ls;
  88 -}
  89 -
  90  struct dlm_ls *dlm_find_lockspace_global(uint32_t id)
  91  {
  92         struct dlm_ls *ls;
  93 @@ -327,6 +311,7 @@ static void remove_lockspace(struct dlm_ls *ls)
  94         for (;;) {
  95                 spin_lock(&lslist_lock);
  96                 if (ls->ls_count == 0) {
  97 +                       WARN_ON(ls->ls_create_count != 0);
  98                         list_del(&ls->ls_list);
  99                         spin_unlock(&lslist_lock);
 100                         return;
 101 @@ -381,7 +366,7 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
 102                          uint32_t flags, int lvblen)
 103  {
 104         struct dlm_ls *ls;
 105 -       int i, size, error = -ENOMEM;
 106 +       int i, size, error;
 107         int do_unreg = 0;
 108
 109         if (namelen > DLM_LOCKSPACE_LEN)
 110 @@ -393,12 +378,32 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
 111         if (!try_module_get(THIS_MODULE))
 112                 return -EINVAL;
 113
 114 -       ls = dlm_find_lockspace_name(name, namelen);
 115 -       if (ls) {
 116 -               *lockspace = ls;
 117 +       error = 0;
 118 +
 119 +       spin_lock(&lslist_lock);
 120 +       list_for_each_entry(ls, &lslist, ls_list) {
 121 +               WARN_ON(ls->ls_create_count <= 0);
 122 +               if (ls->ls_namelen != namelen)
 123 +                       continue;
 124 +               if (memcmp(ls->ls_name, name, namelen))
 125 +                       continue;
 126 +               if (flags & DLM_LSFL_NEWEXCL) {
 127 +                       error = -EEXIST;
 128 +                       break;
 129 +               }
 130 +               ls->ls_create_count++;
 131                 module_put(THIS_MODULE);
 132 -               return -EEXIST;
 133 +               error = 1; /* not an error, return 0 */
 134 +               break;
 135         }
 136 +       spin_unlock(&lslist_lock);
 137 +
 138 +       if (error < 0)
 139 +               goto out;
 140 +       if (error)
 141 +               goto ret_zero;
 142 +
 143 +       error = -ENOMEM;
 144
 145         ls = kzalloc(sizeof(struct dlm_ls) + namelen, GFP_KERNEL);
 146         if (!ls)
 147 @@ -418,8 +423,9 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
 148                 ls->ls_allocation = GFP_KERNEL;
 149
 150         /* ls_exflags are forced to match among nodes, and we don't
 151 -          need to require all nodes to have TIMEWARN or FS set */
 152 -       ls->ls_exflags = (flags & ~(DLM_LSFL_TIMEWARN | DLM_LSFL_FS));
 153 +          need to require all nodes to have some flags set */
 154 +       ls->ls_exflags = (flags & ~(DLM_LSFL_TIMEWARN | DLM_LSFL_FS |
 155 +                                   DLM_LSFL_NEWEXCL));
 156
 157         size = dlm_config.ci_rsbtbl_size;
 158         ls->ls_rsbtbl_size = size;
 159 @@ -510,6 +516,7 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
 160         down_write(&ls->ls_in_recovery);
 161
 162         spin_lock(&lslist_lock);
 163 +       ls->ls_create_count = 1;
 164         list_add(&ls->ls_list, &lslist);
 165         spin_unlock(&lslist_lock);
 166
 167 @@ -548,7 +555,7 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
 168         dlm_create_debug_file(ls);
 169
 170         log_debug(ls, "join complete");
 171 -
 172 + ret_zero:
 173         *lockspace = ls;
 174         return 0;
 175
 176 @@ -635,11 +642,32 @@ static int release_lockspace(struct dlm_ls *ls, int force)
 177         struct dlm_lkb *lkb;
 178         struct dlm_rsb *rsb;
 179         struct list_head *head;
 180 -       int i;
 181 -       int busy = lockspace_busy(ls);
 182 +       int i, busy, rv;
 183 +
 184 +       busy = lockspace_busy(ls);
 185 +
 186 +       spin_lock(&lslist_lock);
 187 +       if (ls->ls_create_count == 1) {
 188 +               if (busy > force)
 189 +                       rv = -EBUSY;
 190 +               else {
 191 +                       /* remove_lockspace takes ls off lslist */
 192 +                       ls->ls_create_count = 0;
 193 +                       rv = 0;
 194 +               }
 195 +       } else if (ls->ls_create_count > 1) {
 196 +               rv = --ls->ls_create_count;
 197 +       } else {
 198 +               rv = -EINVAL;
 199 +       }
 200 +       spin_unlock(&lslist_lock);
 201 +
 202 +       if (rv) {
 203 +               log_debug(ls, "release_lockspace no remove %d", rv);
 204 +               return rv;
 205 +       }
 206
 207 -       if (busy > force)
 208 -               return -EBUSY;
 209 +       dlm_device_deregister(ls);
 210
 211         if (force < 3)
 212                 do_uevent(ls, 0);
 213 @@ -720,15 +748,10 @@ static int release_lockspace(struct dlm_ls *ls, int force)
 214         dlm_clear_members(ls);
 215         dlm_clear_members_gone(ls);
 216         kfree(ls->ls_node_array);
 217 +       log_debug(ls, "release_lockspace final free");
 218         kobject_put(&ls->ls_kobj);
 219         /* The ls structure will be freed when the kobject is done with */
 220
 221 -       mutex_lock(&ls_lock);
 222 -       ls_count--;
 223 -       if (!ls_count)
 224 -               threads_stop();
 225 -       mutex_unlock(&ls_lock);
 226 -
 227         module_put(THIS_MODULE);
 228         return 0;
 229  }
 230 @@ -750,11 +773,21 @@ static int release_lockspace(struct dlm_ls *ls, int force)
 231  int dlm_release_lockspace(void *lockspace, int force)
 232  {
 233         struct dlm_ls *ls;
 234 +       int error;
 235
 236         ls = dlm_find_lockspace_local(lockspace);
 237         if (!ls)
 238                 return -EINVAL;
 239         dlm_put_lockspace(ls);
 240 -       return release_lockspace(ls, force);
 241 +
 242 +       mutex_lock(&ls_lock);
 243 +       error = release_lockspace(ls, force);
 244 +       if (!error)
 245 +               ls_count--;
 246 +       else if (!ls_count)
 247 +               threads_stop();
 248 +       mutex_unlock(&ls_lock);
 249 +
 250 +       return error;
 251  }
 252
 253 diff --git a/fs/dlm/user.c b/fs/dlm/user.c
 254 index 34f14a1..6542110 100644
 255 --- a/fs/dlm/user.c
 256 +++ b/fs/dlm/user.c
 257 @@ -1,5 +1,5 @@
 258  /*
 259 - * Copyright (C) 2006-2007 Red Hat, Inc.  All rights reserved.
 260 + * Copyright (C) 2006-2008 Red Hat, Inc.  All rights reserved.
 261   *
 262   * This copyrighted material is made available to anyone wishing to use,
 263   * modify, copy, or redistribute it subject to the terms and conditions
 264 @@ -340,10 +340,15 @@ static int device_user_deadlock(struct dlm_user_proc *proc,
 265         return error;
 266  }
 267
 268 -static int create_misc_device(struct dlm_ls *ls, char *name)
 269 +static int dlm_device_register(struct dlm_ls *ls, char *name)
 270  {
 271         int error, len;
 272
 273 +       /* The device is already registered.  This happens when the
 274 +          lockspace is created multiple times from userspace. */
 275 +       if (ls->ls_device.name)
 276 +               return 0;
 277 +
 278         error = -ENOMEM;
 279         len = strlen(name) + strlen(name_prefix) + 2;
 280         ls->ls_device.name = kzalloc(len, GFP_KERNEL);
 281 @@ -363,6 +368,22 @@ fail:
 282         return error;
 283  }
 284
 285 +int dlm_device_deregister(struct dlm_ls *ls)
 286 +{
 287 +       int error;
 288 +
 289 +       /* The device is not registered.  This happens when the lockspace
 290 +          was never used from userspace, or when device_create_lockspace()
 291 +          calls dlm_release_lockspace() after the register fails. */
 292 +       if (!ls->ls_device.name)
 293 +               return 0;
 294 +
 295 +       error = misc_deregister(&ls->ls_device);
 296 +       if (!error)
 297 +               kfree(ls->ls_device.name);
 298 +       return error;
 299 +}
 300 +
 301  static int device_user_purge(struct dlm_user_proc *proc,
 302                              struct dlm_purge_params *params)
 303  {
 304 @@ -397,7 +418,7 @@ static int device_create_lockspace(struct dlm_lspace_params *params)
 305         if (!ls)
 306                 return -ENOENT;
 307
 308 -       error = create_misc_device(ls, params->name);
 309 +       error = dlm_device_register(ls, params->name);
 310         dlm_put_lockspace(ls);
 311
 312         if (error)
 313 @@ -421,31 +442,22 @@ static int device_remove_lockspace(struct dlm_lspace_params *params)
 314         if (!ls)
 315                 return -ENOENT;
 316
 317 -       /* Deregister the misc device first, so we don't have
 318 -        * a device that's not attached to a lockspace. If
 319 -        * dlm_release_lockspace fails then we can recreate it
 320 -        */
 321 -       error = misc_deregister(&ls->ls_device);
 322 -       if (error) {
 323 -               dlm_put_lockspace(ls);
 324 -               goto out;
 325 -       }
 326 -       kfree(ls->ls_device.name);
 327 -
 328         if (params->flags & DLM_USER_LSFLG_FORCEFREE)
 329                 force = 2;
 330
 331         lockspace = ls->ls_local_handle;
 332 +       dlm_put_lockspace(ls);
 333
 334 -       /* dlm_release_lockspace waits for references to go to zero,
 335 -          so all processes will need to close their device for the ls
 336 -          before the release will procede */
 337 +       /* The final dlm_release_lockspace waits for references to go to
 338 +          zero, so all processes will need to close their device for the
 339 +          ls before the release will proceed.  release also calls the
 340 +          device_deregister above.  Converting a positive return value
 341 +          from release to zero means that userspace won't know when its
 342 +          release was the final one, but it shouldn't need to know. */
 343
 344 -       dlm_put_lockspace(ls);
 345         error = dlm_release_lockspace(lockspace, force);
 346 -       if (error)
 347 -               create_misc_device(ls, ls->ls_name);
 348 - out:
 349 +       if (error > 0)
 350 +               error = 0;
 351         return error;
 352  }
 353
 354 diff --git a/fs/dlm/user.h b/fs/dlm/user.h
 355 index d38e9f3..c528b6b 100644
 356 --- a/fs/dlm/user.h
 357 +++ b/fs/dlm/user.h
 358 @@ -1,5 +1,5 @@
 359  /*
 360 - * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
 361 + * Copyright (C) 2006-2008 Red Hat, Inc.  All rights reserved.
 362   *
 363   * This copyrighted material is made available to anyone wishing to use,
 364   * modify, copy, or redistribute it subject to the terms and conditions
 365 @@ -12,5 +12,6 @@
 366  void dlm_user_add_ast(struct dlm_lkb *lkb, int type);
 367  int dlm_user_init(void);
 368  void dlm_user_exit(void);
 369 +int dlm_device_deregister(struct dlm_ls *ls);
 370
 371  #endif
 372 diff --git a/fs/gfs2/locking/dlm/mount.c b/fs/gfs2/locking/dlm/mount.c
 373 index 09d78c2..0c4cbe6 100644
 374 --- a/fs/gfs2/locking/dlm/mount.c
 375 +++ b/fs/gfs2/locking/dlm/mount.c
 376 @@ -144,7 +144,8 @@ static int gdlm_mount(char *table_name, char *host_data,
 377
 378         error = dlm_new_lockspace(ls->fsname, strlen(ls->fsname),
 379                                   &ls->dlm_lockspace,
 380 -                                 DLM_LSFL_FS | (nodir ? DLM_LSFL_NODIR : 0),
 381 +                                 DLM_LSFL_FS | DLM_LSFL_NEWEXCL |
 382 +                                 (nodir ? DLM_LSFL_NODIR : 0),
 383                                   GDLM_LVB_SIZE);
 384         if (error) {
 385                 log_error("dlm_new_lockspace error %d", error);
 386 diff --git a/include/linux/dlm.h b/include/linux/dlm.h
 387 index 203a025..b9cd386 100644
 388 --- a/include/linux/dlm.h
 389 +++ b/include/linux/dlm.h
 390 @@ -2,7 +2,7 @@
 391  *******************************************************************************
 392  **
 393  **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
 394 -**  Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
 395 +**  Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
 396  **
 397  **  This copyrighted material is made available to anyone wishing to use,
 398  **  modify, copy, or redistribute it subject to the terms and conditions
 399 @@ -65,9 +65,12 @@ struct dlm_lksb {
 400         char *   sb_lvbptr;
 401  };
 402
 403 +/* dlm_new_lockspace() flags */
 404 +
 405  #define DLM_LSFL_NODIR         0x00000001
 406  #define DLM_LSFL_TIMEWARN      0x00000002
 407  #define DLM_LSFL_FS            0x00000004
 408 +#define DLM_LSFL_NEWEXCL       0x00000008
 409
 410  #ifdef __KERNEL__
 411
 412 diff --git a/include/linux/dlm_device.h b/include/linux/dlm_device.h
 413 index c603450..3060783 100644
 414 --- a/include/linux/dlm_device.h
 415 +++ b/include/linux/dlm_device.h
 416 @@ -26,7 +26,7 @@
 417  /* Version of the device interface */
 418  #define DLM_DEVICE_VERSION_MAJOR 6
 419  #define DLM_DEVICE_VERSION_MINOR 0
 420 -#define DLM_DEVICE_VERSION_PATCH 0
 421 +#define DLM_DEVICE_VERSION_PATCH 1
 422
 423  /* struct passed to the lock write */
 424  struct dlm_lock_params {
 425 --
 426 1.5.4.5
 427