/** Place a copy of a given object in local physical memory.
* @author Renaud Lottiaux
*
* @param set KDDM set hosting the object.
* @param obj_entry Object entry of the object to get.
* @param objid Identifier of the object to get.
* @param flags Sync / Async request, FT or not, etc...
*
* @return Address of the object if found.
* NULL if the object does not exist.
* Negative value if error.
*
* A object is retreived from a remote node owning a copy. If there is
* no copy in the cluster and the NO_FT flag is not set,
* the object is created by the IO Linker. Otherwise NULL is returned.
*/
void *generic_kddm_get_object(struct kddm_set *set,
objid_t objid,
int flags)
{
struct kddm_obj *obj_entry;
void *object = NULL;
inc_get_object_counter (set);
obj_entry = __get_kddm_obj_entry(set, objid);
if (likely(obj_entry != NULL))
goto try_again;
if (I_AM_DEFAULT_OWNER(set, objid) && (flags & KDDM_NO_FT_REQ) &&
!(flags & KDDM_SEND_OWNERSHIP))
return NULL;
obj_entry = __get_alloc_kddm_obj_entry(set, objid);
try_again:
switch (OBJ_STATE(obj_entry)) {
case INV_COPY:
request_object_on_read(set, obj_entry, objid, flags);
kddm_change_obj_state(set, obj_entry, objid, WAIT_OBJ_READ);
/* Fall through */
case WAIT_ACK_WRITE:
case WAIT_OBJ_WRITE:
case WAIT_OBJ_READ:
case INV_FILLING:
if (flags & KDDM_ASYNC_REQ)
goto exit_no_freeze;
sleep_on_kddm_obj(set, obj_entry, objid, flags);
if ((flags & KDDM_NO_FT_REQ) &&
((OBJ_STATE(obj_entry) == INV_COPY) ||
(OBJ_STATE(obj_entry) == INV_OWNER)))
goto exit;
if (!(OBJ_STATE(obj_entry) & KDDM_READ_OBJ)) {
/* Argh, object has been invalidated before we
woke up. */
goto try_again;
}
break;
case WAIT_CHG_OWN_ACK:
case READ_COPY:
case READ_OWNER:
case WRITE_OWNER:
case WAIT_ACK_INV:
break;
case WAIT_OBJ_RM_DONE:
case WAIT_OBJ_RM_ACK:
case WAIT_OBJ_RM_ACK2:
sleep_on_kddm_obj(set, obj_entry, objid, flags);
goto try_again;
case WRITE_GHOST:
kddm_change_obj_state(set, obj_entry, objid, WRITE_OWNER);
break;
case INV_OWNER: /* First Touch */
if (flags & KDDM_NO_FT_REQ)
goto exit;
/*** The object can be created on the local node ***/
if (object_first_touch(set, obj_entry, objid,
READ_OWNER, flags) != 0)
BUG();
break;
default:
STATE_MACHINE_ERROR(set->id, objid, obj_entry);
break;
}
exit:
if (flags & KDDM_ASYNC_REQ)
goto exit_no_freeze;
if (check_sleep_on_local_exclusive(set, obj_entry, objid, flags))
goto try_again;
if (!(flags & KDDM_NO_FREEZE))
set_object_frozen(obj_entry, set);
exit_no_freeze:
object = obj_entry->object;
put_kddm_obj_entry(set, obj_entry, objid);
return object;
}
/** Get a copy of a object and invalidate any other existing copy.
* @author Renaud Lottiaux
*
* @param set KDDM set hosting the object.
* @param obj_entry Object entry of the object to grab.
* @param objid Identifier of the object to grab.
* @param flags Sync / Async request, FT or not, etc...
*
* @return Address of the object if found.
* NULL if the object does not exist.
* Negative value if error.
*/
void *generic_kddm_grab_object(struct kddm_set *set,
objid_t objid,
int flags)
{
struct kddm_obj *obj_entry;
void *object;
int retry;
inc_grab_object_counter(set);
obj_entry = __get_kddm_obj_entry(set, objid);
if (likely(obj_entry != NULL))
goto try_again;
if (I_AM_DEFAULT_OWNER(set, objid) && (flags & KDDM_NO_FT_REQ) &&
!(flags & KDDM_SEND_OWNERSHIP))
return NULL;
obj_entry = __get_alloc_kddm_obj_entry(set, objid);
try_again:
switch (OBJ_STATE(obj_entry)) {
case READ_COPY:
if (object_frozen(obj_entry, set)) {
if (flags & KDDM_ASYNC_REQ)
BUG();
goto sleep;
}
case INV_COPY:
request_object_on_write(set, obj_entry, objid, flags);
CLEAR_SET(COPYSET(obj_entry));
kddm_change_obj_state(set, obj_entry, objid, WAIT_OBJ_WRITE);
if (flags & KDDM_TRY_GRAB)
goto sleep_on_wait_page;
/* Else Fall through */
case WAIT_ACK_WRITE:
case WAIT_OBJ_WRITE:
case INV_FILLING:
if (flags & KDDM_TRY_GRAB)
goto exit_try_failed;
if (flags & KDDM_ASYNC_REQ)
goto exit_no_freeze;
sleep_on_wait_page:
sleep_on_kddm_obj(set, obj_entry, objid, flags);
if (OBJ_STATE(obj_entry) == WRITE_OWNER) {
obj_entry = check_cow (set, obj_entry, objid, flags,
&retry);
if (retry)
goto try_again;
break;
}
if (flags & KDDM_NO_FT_REQ) {
if (OBJ_STATE(obj_entry) == INV_OWNER)
break;
if (OBJ_STATE(obj_entry) == INV_COPY) {
if (!(flags & KDDM_SEND_OWNERSHIP))
break;
BUG();
}
}
if (flags & KDDM_TRY_GRAB)
goto exit_try_failed;
/* Argh, object has been invalidated before we woke up. */
goto try_again;
case INV_OWNER:
if (flags & KDDM_NO_FT_REQ)
break;
/*** The object can be created on the local node ***/
if (object_first_touch(set, obj_entry, objid,
WRITE_OWNER, flags) != 0)
BUG();
break;
case READ_OWNER:
obj_entry = check_cow (set, obj_entry, objid, flags,
&retry);
if (retry)
goto try_again;
if (!OBJ_EXCLUSIVE(obj_entry)) {
kddm_change_obj_state(set, obj_entry, objid,
WAIT_ACK_WRITE);
request_copies_invalidation(set, obj_entry, objid,
kerrighed_node_id);
if (flags & KDDM_ASYNC_REQ)
goto exit_no_freeze;
sleep_on_kddm_obj(set, obj_entry, objid, flags);
if (OBJ_STATE(obj_entry) != WRITE_OWNER) {
/* Argh, object has been invalidated before
we woke up. */
goto try_again;
}
} else
kddm_change_obj_state(set, obj_entry, objid,
WRITE_OWNER);
break;
case WRITE_OWNER:
obj_entry = check_cow (set, obj_entry, objid, flags, &retry);
if (retry)
goto try_again;
break;
case WRITE_GHOST:
obj_entry = check_cow (set, obj_entry, objid, flags, &retry);
if (retry)
goto try_again;
kddm_change_obj_state(set, obj_entry, objid, WRITE_OWNER);
break;
case WAIT_ACK_INV:
case WAIT_OBJ_READ:
if (flags & KDDM_TRY_GRAB)
goto exit_try_failed;
/* Fall through */
case WAIT_OBJ_RM_DONE:
case WAIT_OBJ_RM_ACK:
case WAIT_OBJ_RM_ACK2:
case WAIT_CHG_OWN_ACK:
sleep:
if (flags & KDDM_ASYNC_REQ)
goto exit_no_freeze;
sleep_on_kddm_obj(set, obj_entry, objid, flags);
goto try_again;
default:
STATE_MACHINE_ERROR(set->id, objid, obj_entry);
break;
}
if (flags & KDDM_ASYNC_REQ)
goto exit_no_freeze;
if (object_frozen(obj_entry, set) &&
(flags & KDDM_TRY_GRAB) &&
(kddm_local_exclusive (set)))
goto exit_try_failed;
if (check_sleep_on_local_exclusive(set, obj_entry, objid, flags))
goto try_again;
if (!(flags & KDDM_NO_FREEZE))
set_object_frozen(obj_entry, set);
exit_no_freeze:
object = obj_entry->object;
put_kddm_obj_entry(set, obj_entry, objid);
return object;
exit_try_failed:
put_kddm_obj_entry(set, obj_entry, objid);
return ERR_PTR(-EBUSY);
}
