From db05628435aa761d30b4eae481a82befe7a8492a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 20 Apr 2022 06:27:12 +0200 Subject: blk-cgroup: move blkcg_{get,set}_fc_appid out of line No need to have these helpers inline. Also remove the stubs and just use an IS_ENABLED for the get side (the set side already is only built conditionlly). Signed-off-by: Christoph Hellwig Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20220420042723.1010598-5-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-cgroup-fc-appid.c | 57 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 block/blk-cgroup-fc-appid.c (limited to 'block/blk-cgroup-fc-appid.c') diff --git a/block/blk-cgroup-fc-appid.c b/block/blk-cgroup-fc-appid.c new file mode 100644 index 000000000000..760a2e1878dd --- /dev/null +++ b/block/blk-cgroup-fc-appid.c @@ -0,0 +1,57 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "blk-cgroup.h" + +/** + * blkcg_set_fc_appid - set the fc_app_id field associted to blkcg + * @app_id: application identifier + * @cgrp_id: cgroup id + * @app_id_len: size of application identifier + */ +int blkcg_set_fc_appid(char *app_id, u64 cgrp_id, size_t app_id_len) +{ + struct cgroup *cgrp; + struct cgroup_subsys_state *css; + struct blkcg *blkcg; + int ret = 0; + + if (app_id_len > FC_APPID_LEN) + return -EINVAL; + + cgrp = cgroup_get_from_id(cgrp_id); + if (!cgrp) + return -ENOENT; + css = cgroup_get_e_css(cgrp, &io_cgrp_subsys); + if (!css) { + ret = -ENOENT; + goto out_cgrp_put; + } + blkcg = css_to_blkcg(css); + /* + * There is a slight race condition on setting the appid. + * Worst case an I/O may not find the right id. + * This is no different from the I/O we let pass while obtaining + * the vmid from the fabric. + * Adding the overhead of a lock is not necessary. + */ + strlcpy(blkcg->fc_app_id, app_id, app_id_len); + css_put(css); +out_cgrp_put: + cgroup_put(cgrp); + return ret; +} +EXPORT_SYMBOL_GPL(blkcg_set_fc_appid); + +/** + * blkcg_get_fc_appid - get the fc app identifier associated with a bio + * @bio: target bio + * + * On success return the fc_app_id, on failure return NULL + */ +char *blkcg_get_fc_appid(struct bio *bio) +{ + if (!bio->bi_blkg || bio->bi_blkg->blkcg->fc_app_id[0] == '\0') + return NULL; + return bio->bi_blkg->blkcg->fc_app_id; +} +EXPORT_SYMBOL_GPL(blkcg_get_fc_appid); -- cgit