/* Enable/disable zswap (disabled by default) */
static bool zswap_enabled;
-module_param_named(enabled, zswap_enabled, bool, 0644);
+static int zswap_enabled_param_set(const char *,
+ const struct kernel_param *);
+static struct kernel_param_ops zswap_enabled_param_ops = {
+ .set = zswap_enabled_param_set,
+ .get = param_get_bool,
+};
+module_param_cb(enabled, &zswap_enabled_param_ops, &zswap_enabled, 0644);
/* Crypto compressor to use */
#define ZSWAP_COMPRESSOR_DEFAULT "lzo"
static LIST_HEAD(zswap_pools);
/* protects zswap_pools list modification */
static DEFINE_SPINLOCK(zswap_pools_lock);
+/* pool counter to provide unique names to zpool */
+static atomic_t zswap_pools_count = ATOMIC_INIT(0);
/* used by param callback function */
static bool zswap_init_started;
+/* fatal error during init */
+static bool zswap_init_failed;
+
/*********************************
* helpers and fwd declarations
**********************************/
static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
{
struct zswap_pool *pool;
+ char name[38]; /* 'zswap' + 32 char (max) num + \0 */
gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM;
pool = kzalloc(sizeof(*pool), GFP_KERNEL);
return NULL;
}
- pool->zpool = zpool_create_pool(type, "zswap", gfp, &zswap_zpool_ops);
+ /* unique name for each pool specifically required by zsmalloc */
+ snprintf(name, 38, "zswap%x", atomic_inc_return(&zswap_pools_count));
+
+ pool->zpool = zpool_create_pool(type, name, gfp, &zswap_zpool_ops);
if (!pool->zpool) {
pr_err("%s zpool not available\n", type);
goto error;
char *s = strstrip((char *)val);
int ret;
+ if (zswap_init_failed) {
+ pr_err("can't set param, initialization failed\n");
+ return -ENODEV;
+ }
+
/* no change required */
if (!strcmp(s, *(char **)kp->arg))
return 0;
return __zswap_param_set(val, kp, NULL, zswap_compressor);
}
+static int zswap_enabled_param_set(const char *val,
+ const struct kernel_param *kp)
+{
+ if (zswap_init_failed) {
+ pr_err("can't enable, initialization failed\n");
+ return -ENODEV;
+ }
+
+ return param_set_bool(val, kp);
+}
+
/*********************************
* writeback code
**********************************/
dstmem_fail:
zswap_entry_cache_destroy();
cache_fail:
+ /* if built-in, we aren't unloaded on failure; don't allow use */
+ zswap_init_failed = true;
+ zswap_enabled = false;
return -ENOMEM;
}
/* must be late so crypto has time to come up */