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authorChristoph Hellwig <hch@lst.de>2022-04-20 07:27:12 +0300
committerJens Axboe <axboe@kernel.dk>2022-05-02 23:06:20 +0300
commitdb05628435aa761d30b4eae481a82befe7a8492a (patch)
tree8701ff5f82134e18c58e6b916f92e7c4c22be019 /block
parentc814153c83a892dfd42026eaa661ae2c1f298792 (diff)
downloadlinux-db05628435aa761d30b4eae481a82befe7a8492a.tar.xz
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 <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
-rw-r--r--block/Makefile1
-rw-r--r--block/blk-cgroup-fc-appid.c57
2 files changed, 58 insertions, 0 deletions
diff --git a/block/Makefile b/block/Makefile
index 3950ecbc5c26..4e01bb71ad6e 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_BLK_DEV_BSG_COMMON) += bsg.o
obj-$(CONFIG_BLK_DEV_BSGLIB) += bsg-lib.o
obj-$(CONFIG_BLK_CGROUP) += blk-cgroup.o
obj-$(CONFIG_BLK_CGROUP_RWSTAT) += blk-cgroup-rwstat.o
+obj-$(CONFIG_BLK_CGROUP_FC_APPID) += blk-cgroup-fc-appid.o
obj-$(CONFIG_BLK_DEV_THROTTLING) += blk-throttle.o
obj-$(CONFIG_BLK_CGROUP_IOPRIO) += blk-ioprio.o
obj-$(CONFIG_BLK_CGROUP_IOLATENCY) += blk-iolatency.o
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);