From: Mike Christie Date: Thu, 12 Oct 2023 15:06:00 +0000 (-0500) Subject: ublk: Make ublks_max configurable X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=6eba24aeb5e2fc582dd83021795befc1adaede20;p=linux.git ublk: Make ublks_max configurable We are converting tcmu applications to ublk, but have systems with up to 1k devices. This patch allows us to configure the ublks_max from userspace with the ublks_max modparam. Signed-off-by: Mike Christie Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20231012150600.6198-3-michael.christie@oracle.com Signed-off-by: Jens Axboe --- diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index ba7c6f9ee136e..b0bbda08ad453 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -2940,7 +2940,22 @@ static void __exit ublk_exit(void) module_init(ublk_init); module_exit(ublk_exit); -module_param(ublks_max, int, 0444); +static int ublk_set_max_ublks(const char *buf, const struct kernel_param *kp) +{ + return param_set_uint_minmax(buf, kp, 0, UBLK_MAX_UBLKS); +} + +static int ublk_get_max_ublks(char *buf, const struct kernel_param *kp) +{ + return sysfs_emit(buf, "%u\n", ublks_max); +} + +static const struct kernel_param_ops ublk_max_ublks_ops = { + .set = ublk_set_max_ublks, + .get = ublk_get_max_ublks, +}; + +module_param_cb(ublks_max, &ublk_max_ublks_ops, &ublks_max, 0644); MODULE_PARM_DESC(ublks_max, "max number of ublk devices allowed to add(default: 64)"); MODULE_AUTHOR("Ming Lei ");