From 3dbbca75ed679d629d0c2895a42b55657873d04f Mon Sep 17 00:00:00 2001 From: Muneendra Kumar Date: Tue, 8 Jun 2021 10:05:46 +0530 Subject: scsi: nvme: Added a new sysfs attribute appid_store Add a new sysfs attribute, appid_store, which can be used to set the application identifier in the blkcg associated with a cgroup id. Below is the interface provided to set the app_id: echo ":" >> /sys/class/fc/fc_udev_device/appid_store echo "457E:100000109b521d27" >> /sys/class/fc/fc_udev_device/appid_store Link: https://lore.kernel.org/r/20210608043556.274139-4-muneendra.kumar@broadcom.com Reviewed-by: Himanshu Madhani Reviewed-by: Hannes Reinecke Signed-off-by: Muneendra Kumar Signed-off-by: Martin K. Petersen --- drivers/nvme/host/fc.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 71 insertions(+), 1 deletion(-) (limited to 'drivers/nvme') diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c index d9ab9e7871d0..835b563d084e 100644 --- a/drivers/nvme/host/fc.c +++ b/drivers/nvme/host/fc.c @@ -9,7 +9,7 @@ #include #include #include - +#include #include "nvme.h" #include "fabrics.h" #include @@ -3787,10 +3787,80 @@ process_local_list: return count; } + +/* Parse the cgroup id from a buf and return the length of cgrpid */ +static int fc_parse_cgrpid(const char *buf, u64 *id) +{ + char cgrp_id[16+1]; + int cgrpid_len, j; + + memset(cgrp_id, 0x0, sizeof(cgrp_id)); + for (cgrpid_len = 0, j = 0; cgrpid_len < 17; cgrpid_len++) { + if (buf[cgrpid_len] != ':') + cgrp_id[cgrpid_len] = buf[cgrpid_len]; + else { + j = 1; + break; + } + } + if (!j) + return -EINVAL; + if (kstrtou64(cgrp_id, 16, id) < 0) + return -EINVAL; + return cgrpid_len; +} + +/* + * fc_update_appid: Parse and update the appid in the blkcg associated with + * cgroupid. + * @buf: buf contains both cgrpid and appid info + * @count: size of the buffer + */ +static int fc_update_appid(const char *buf, size_t count) +{ + u64 cgrp_id; + int appid_len = 0; + int cgrpid_len = 0; + char app_id[FC_APPID_LEN]; + int ret = 0; + + if (buf[count-1] == '\n') + count--; + + if ((count > (16+1+FC_APPID_LEN)) || (!strchr(buf, ':'))) + return -EINVAL; + + cgrpid_len = fc_parse_cgrpid(buf, &cgrp_id); + if (cgrpid_len < 0) + return -EINVAL; + appid_len = count - cgrpid_len - 1; + if (appid_len > FC_APPID_LEN) + return -EINVAL; + + memset(app_id, 0x0, sizeof(app_id)); + memcpy(app_id, &buf[cgrpid_len+1], appid_len); + ret = blkcg_set_fc_appid(app_id, cgrp_id, sizeof(app_id)); + if (ret < 0) + return ret; + return count; +} + +static ssize_t fc_appid_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + int ret = 0; + + ret = fc_update_appid(buf, count); + if (ret < 0) + return -EINVAL; + return count; +} static DEVICE_ATTR(nvme_discovery, 0200, NULL, nvme_fc_nvme_discovery_store); +static DEVICE_ATTR(appid_store, 0200, NULL, fc_appid_store); static struct attribute *nvme_fc_attrs[] = { &dev_attr_nvme_discovery.attr, + &dev_attr_appid_store.attr, NULL }; -- cgit v1.2.3