[PATCH v7 5/9] coresight: configfs: Add attributes for unload operations
Mike Leach
mike.leach at linaro.org
Wed Nov 27 05:42:52 PST 2024
Add attributes to view last loaded configuration, and to unload
last loaded configuration, if it was loaded as a dynamic config table.
Signed-off-by: Mike Leach <mike.leach at linaro.org>
---
.../coresight/coresight-syscfg-configfs.c | 62 +++++++++++++++++++
1 file changed, 62 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.c b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
index 83da4820be6d..d7883fe802b5 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
+++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
@@ -790,9 +790,71 @@ static void cscfg_destroy_feature_group(struct config_group *feat_group)
kfree(feat_view);
}
+/* Attributes in configfs that allow load and unload of configuration tables */
+
+static ssize_t
+cscfg_cfg_unload_last_table_store(struct config_item *item, const char *page, size_t count)
+{
+ int err;
+ unsigned long val;
+
+ err = kstrtoul(page, 0, &val);
+ if (err)
+ return err;
+
+ if (val > 0) {
+ /* schedule unload of last dynamic loaded configuration */
+ err = cscfg_sched_dyn_unload_cfg_table();
+ if (!err)
+ err = count;
+ } else
+ err = -EINVAL;
+
+ return err;
+}
+CONFIGFS_ATTR_WO(cscfg_cfg_, unload_last_table);
+
+static ssize_t cscfg_cfg_show_last_load_show(struct config_item *item, char *page)
+{
+ struct cscfg_load_owner_info *owner_info = 0;
+ ssize_t size = 0;
+
+ /* ensure we cannot read last load while loading / unloading */
+ if (!mutex_trylock(&cfs_mutex))
+ return -EBUSY;
+
+ /* check dyn load / unload ops are permitted & no ongoing unload */
+ if (!cscfg_load_ops_permitted()) {
+ size = -EBUSY;
+ goto exit_unlock;
+ }
+
+ /* find the last loaded owner info block */
+ owner_info = cscfg_find_last_loaded_cfg_owner();
+ if (!owner_info) {
+ size = scnprintf(page, PAGE_SIZE,
+ "Failed to find any loaded configuration\n");
+ goto exit_unlock;
+ }
+
+ /* get string desc of last unload configuration from owner info */
+ size = cscfg_get_owner_info_str(owner_info, page, PAGE_SIZE);
+
+exit_unlock:
+ mutex_unlock(&cfs_mutex);
+ return size;
+}
+CONFIGFS_ATTR_RO(cscfg_cfg_, show_last_load);
+
+static struct configfs_attribute *cscfg_config_configfs_attrs[] = {
+ &cscfg_cfg_attr_unload_last_table,
+ &cscfg_cfg_attr_show_last_load,
+ NULL,
+};
static struct config_item_type cscfg_configs_load_type = {
.ct_owner = THIS_MODULE,
+ .ct_attrs = cscfg_config_configfs_attrs,
};
/* configurations group */
--
2.25.1
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