Commit 9317d001 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

nvme-fc: fix the fc_appid_store return value 



"nvme-fc: fold t fc_update_appid into fc_appid_store" accidentally
changed the userspace interface for the appid attribute, because the code
that decrements "count" to remove a trailing '\n' in the parsing results
in the decremented value being incorrectly be returned from the sysfs
write.  Fix this by keeping an orig_count variable for the full length
of the write.

Fixes: c814153c ("nvme-fc: fold t fc_update_appid into fc_appid_store")
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: default avatarEwan D. Milne <emilne@redhat.com>
Reviewed-by: default avatarJames Smart <jsmart2021@gmail.com>
Tested-by: default avatarMuneendra Kumar M <muneendra.kumar@broadcom.com>
parent 6fb271f1

drivers/nvme/host/fc.c

+2 −1
Original line number Diff line number Diff line
@@ -3880,6 +3880,7 @@ static int fc_parse_cgrpid(const char *buf, u64 *id) 
static ssize_t fc_appid_store(struct device *dev,

		struct device_attribute *attr, const char *buf, size_t count)

{

	size_t orig_count = count;

	u64 cgrp_id;

	int appid_len = 0;

	int cgrpid_len = 0;
@@ -3904,7 +3905,7 @@ static ssize_t fc_appid_store(struct device *dev, 
	ret = blkcg_set_fc_appid(app_id, cgrp_id, sizeof(app_id));

	if (ret < 0)

		return ret;

	return count;

	return orig_count;

}

static DEVICE_ATTR(appid_store, 0200, NULL, fc_appid_store);

#endif /* CONFIG_BLK_CGROUP_FC_APPID */