static void iostash_exit(void)
{
DBG("++ iostash_exit() ++\n");
_free_resource();
_destroy_iostash_kobjects();
DBG("-- iostash_exit() ++\n");
}
/*
decrement the reference count of a resource.
remove the resource entry if the reference count
reaches zero.
*/
F8RES_API __bool unload_resource(
const f8_uuid * id
)
{
RESMAP::iterator it;
F8_RESOURCE * res;
it = g_Resources.find(*id);
if(it == g_Resources.end()){
return __false;
}
res = &it->second;
assert(res->refcount > 0);
res->refcount--;
if(0 == res->refcount){
/* garbage collection */
if(res->delProc){
res->delProc(id);
}
_free_resource(res);
g_Resources.erase(it);
}
return __true;
}
static int __init iostash_init(void)
{
int ret = -1, i;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)
ERR("Kernel version < 2.6.28 not supported.");
return -ENOENT;
#endif
DBG("++ iostash_init() ++\n");
memset(&gctx, 0, sizeof(gctx));
do {
gctx.io_pool = KMEM_CACHE(iostash_bio, 0);
if (!gctx.io_pool) {
ERR("iostash_init: KMEM_CACHE() failed\n");
break;
}
gctx.io_client = dm_io_client_create();
if (IS_ERR(gctx.io_client)) {
ERR("iostash_init: dm_io_client() failed\n");
break;
}
gctx.sce = sce_create();
if (!gctx.sce) {
ERR("iostash_init: sce_create() failed\n");
break;
}
gctx.pdm = pdm_create(gctx.sce, poptask_read, poptask_write);
if (_init_iostash_kobjects()) {
ERR("KOBJECT INIT FAILED!");
_destroy_iostash_kobjects();
}
mutex_init(&gctx.ctl_mtx);
for (i = 0; i < IOSTASH_MAXHDD_BCKTS; ++i)
INIT_LIST_HEAD(&gctx.hddtbl.bucket[i]);
for (i = 0; i < IOSTASH_MAXSSD_BCKTS; ++i)
INIT_LIST_HEAD(&gctx.ssdtbl.bucket[i]);
ret = 0;
} while (0);
if (ret) {
_free_resource();
}
DBG("-- iostash_init() returns = %d --\n", ret);
return ret;
}
/*
remove all entries from resource database.
*/
F8RES_API void reset_resources()
{
F8_RESOURCE * res;
RESMAP::iterator it;
it = g_Resources.begin();
while(it != g_Resources.end()){
res = &it->second;
_free_resource(res);
it++;
}
g_Resources.clear();
}
/*
move_resource
will decrement usage count of the source resource,
note this will not necessary cause the source resource
to be deleted, only if its usage count reaches zero.
*/
F8RES_API int move_resource(
const f8_uuid * s,
const f8_uuid * t
)
{
int r;
F8_RESOURCE *tr, *sr;
if(query_resource(t) >= 0){
return F8_NAME_DUPLICATE;
}
sr = _get_res(s);
if(!sr){
return F8_OBJECT_NOT_FOUND;
}
if(!create_resource(t)){
return F8_LOW_MEMORY;
}
if(sr->refcount == 1){
/*
a little optimization, if the reference count of source
is 1, then no actual copy is made, instead, we move
the contents of s to t, and detach s from its contents.
*/
tr = _get_res(t);
delete tr->pItems;
tr->pItems = _get_res(s)->pItems;
sr->pItems = 0;
_free_resource(sr);
r = F8_SUCCESS;
}else{
r = copy_resource(s, t);
}
/*
this will decrement the reference count, and remove the
resource entry if necessary
*/
unload_resource(s);
return r;
}
