From fcbc545959676282e7f46be5c8d8aea26a89ea47 Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Fri, 14 Jul 2017 15:36:56 +0200 Subject: [PATCH] nvmet: preserve controller serial number between reboots The NVMe target has no way to preserve controller serial IDs across reboots which breaks udev scripts doing SYMLINK+="dev/disk/by-id/nvme-$env{ID_SERIAL}-part%n. Export the randomly generated serial number via configfs and allow setting of a serial via configfs to mitigate this breakage. Signed-off-by: Johannes Thumshirn Reviewed-by: Christoph Hellwig Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/nvme/target/configfs.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c index ceee57bb0c24..0a0067e771f5 100644 --- a/drivers/nvme/target/configfs.c +++ b/drivers/nvme/target/configfs.c @@ -686,9 +686,31 @@ static ssize_t nvmet_subsys_attr_version_store(struct config_item *item, } CONFIGFS_ATTR(nvmet_subsys_, attr_version); +static ssize_t nvmet_subsys_attr_serial_show(struct config_item *item, + char *page) +{ + struct nvmet_subsys *subsys = to_subsys(item); + + return snprintf(page, PAGE_SIZE, "%llx\n", subsys->serial); +} + +static ssize_t nvmet_subsys_attr_serial_store(struct config_item *item, + const char *page, size_t count) +{ + struct nvmet_subsys *subsys = to_subsys(item); + + down_write(&nvmet_config_sem); + sscanf(page, "%llx\n", &subsys->serial); + up_write(&nvmet_config_sem); + + return count; +} +CONFIGFS_ATTR(nvmet_subsys_, attr_serial); + static struct configfs_attribute *nvmet_subsys_attrs[] = { &nvmet_subsys_attr_attr_allow_any_host, &nvmet_subsys_attr_attr_version, + &nvmet_subsys_attr_attr_serial, NULL, }; -- 2.20.1