From: Dan Streetman <ddstreet@xxxxxxxx> Subject: zswap: clear compressor or zpool param if invalid at init If either the compressor and/or zpool param are invalid at boot, and their default value is also invalid, set the param to the empty string to indicate there is no compressor and/or zpool configured. This allows users to check the sysfs interface to see which param needs changing. Link: http://lkml.kernel.org/r/20170124200259.16191-4-ddstreet@xxxxxxxx Signed-off-by: Dan Streetman <dan.streetman@xxxxxxxxxxxxx> Cc: Seth Jennings <sjenning@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@xxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/zswap.c | 49 +++++++++++++++++++++++++++++++++++++------------ 1 file changed, 37 insertions(+), 12 deletions(-) diff -puN mm/zswap.c~zswap-clear-compressor-or-zpool-param-if-invalid-at-init mm/zswap.c --- a/mm/zswap.c~zswap-clear-compressor-or-zpool-param-if-invalid-at-init +++ a/mm/zswap.c @@ -76,6 +76,8 @@ static u64 zswap_duplicate_entry; * tunables **********************************/ +#define ZSWAP_PARAM_UNSET "" + /* Enable/disable zswap (disabled by default) */ static bool zswap_enabled; static int zswap_enabled_param_set(const char *, @@ -501,6 +503,17 @@ static struct zswap_pool *zswap_pool_cre gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM; int ret; + if (!zswap_has_pool) { + /* if either are unset, pool initialization failed, and we + * need both params to be set correctly before trying to + * create a pool. + */ + if (!strcmp(type, ZSWAP_PARAM_UNSET)) + return NULL; + if (!strcmp(compressor, ZSWAP_PARAM_UNSET)) + return NULL; + } + pool = kzalloc(sizeof(*pool), GFP_KERNEL); if (!pool) { pr_err("pool alloc failed\n"); @@ -550,28 +563,40 @@ error: static __init struct zswap_pool *__zswap_pool_create_fallback(void) { - if (!crypto_has_comp(zswap_compressor, 0, 0)) { - if (!strcmp(zswap_compressor, ZSWAP_COMPRESSOR_DEFAULT)) { - pr_err("default compressor %s not available\n", - zswap_compressor); - return NULL; - } + bool has_comp, has_zpool; + + has_comp = crypto_has_comp(zswap_compressor, 0, 0); + if (!has_comp && strcmp(zswap_compressor, ZSWAP_COMPRESSOR_DEFAULT)) { pr_err("compressor %s not available, using default %s\n", zswap_compressor, ZSWAP_COMPRESSOR_DEFAULT); param_free_charp(&zswap_compressor); zswap_compressor = ZSWAP_COMPRESSOR_DEFAULT; + has_comp = crypto_has_comp(zswap_compressor, 0, 0); } - if (!zpool_has_pool(zswap_zpool_type)) { - if (!strcmp(zswap_zpool_type, ZSWAP_ZPOOL_DEFAULT)) { - pr_err("default zpool %s not available\n", - zswap_zpool_type); - return NULL; - } + if (!has_comp) { + pr_err("default compressor %s not available\n", + zswap_compressor); + param_free_charp(&zswap_compressor); + zswap_compressor = ZSWAP_PARAM_UNSET; + } + + has_zpool = zpool_has_pool(zswap_zpool_type); + if (!has_zpool && strcmp(zswap_zpool_type, ZSWAP_ZPOOL_DEFAULT)) { pr_err("zpool %s not available, using default %s\n", zswap_zpool_type, ZSWAP_ZPOOL_DEFAULT); param_free_charp(&zswap_zpool_type); zswap_zpool_type = ZSWAP_ZPOOL_DEFAULT; + has_zpool = zpool_has_pool(zswap_zpool_type); } + if (!has_zpool) { + pr_err("default zpool %s not available\n", + zswap_zpool_type); + param_free_charp(&zswap_zpool_type); + zswap_zpool_type = ZSWAP_PARAM_UNSET; + } + + if (!has_comp || !has_zpool) + return NULL; return zswap_pool_create(zswap_zpool_type, zswap_compressor); } _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
