summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLee Duncan <lduncan@suse.com>2016-04-15 01:18:50 (GMT)
committerNicholas Bellinger <nab@linux-iscsi.org>2016-05-10 06:06:15 (GMT)
commita96e9783e05851d5f06da0ae7635aec55a228e3d (patch)
tree20cda8f4cca0cee8d593f1af55f6e7b04b1096d5
parent44549e8f5eea4e0a41b487b63e616cb089922b99 (diff)
downloadlinux-a96e9783e05851d5f06da0ae7635aec55a228e3d.tar.xz
target: make target db location configurable
This commit adds the read-write attribute "dbroot", in the top-level CONFIGFS (core) target directory, normally /sys/kernel/config/target. This attribute defaults to "/var/target" but can be changed by writing a new pathname string to it. Changing this attribute is only allowed when no fabric drivers are loaded and the supplied value specifies an existing directory. Target modules that care about the target database root directory will be modified to use this attribute in a future commit. Signed-off-by: Lee Duncan <lduncan@suse.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
-rw-r--r--drivers/target/target_core_configfs.c62
-rw-r--r--drivers/target/target_core_internal.h6
2 files changed, 68 insertions, 0 deletions
diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
index d498533..73c23c7 100644
--- a/drivers/target/target_core_configfs.c
+++ b/drivers/target/target_core_configfs.c
@@ -99,6 +99,67 @@ static ssize_t target_core_item_version_show(struct config_item *item,
CONFIGFS_ATTR_RO(target_core_item_, version);
+char db_root[DB_ROOT_LEN] = DB_ROOT_DEFAULT;
+static char db_root_stage[DB_ROOT_LEN];
+
+static ssize_t target_core_item_dbroot_show(struct config_item *item,
+ char *page)
+{
+ return sprintf(page, "%s\n", db_root);
+}
+
+static ssize_t target_core_item_dbroot_store(struct config_item *item,
+ const char *page, size_t count)
+{
+ ssize_t read_bytes;
+ struct file *fp;
+
+ mutex_lock(&g_tf_lock);
+ if (!list_empty(&g_tf_list)) {
+ mutex_unlock(&g_tf_lock);
+ pr_err("db_root: cannot be changed: target drivers registered");
+ return -EINVAL;
+ }
+
+ if (count > (DB_ROOT_LEN - 1)) {
+ mutex_unlock(&g_tf_lock);
+ pr_err("db_root: count %d exceeds DB_ROOT_LEN-1: %u\n",
+ (int)count, DB_ROOT_LEN - 1);
+ return -EINVAL;
+ }
+
+ read_bytes = snprintf(db_root_stage, DB_ROOT_LEN, "%s", page);
+ if (!read_bytes) {
+ mutex_unlock(&g_tf_lock);
+ return -EINVAL;
+ }
+ if (db_root_stage[read_bytes - 1] == '\n')
+ db_root_stage[read_bytes - 1] = '\0';
+
+ /* validate new db root before accepting it */
+ fp = filp_open(db_root_stage, O_RDONLY, 0);
+ if (IS_ERR(fp)) {
+ mutex_unlock(&g_tf_lock);
+ pr_err("db_root: cannot open: %s\n", db_root_stage);
+ return -EINVAL;
+ }
+ if (!S_ISDIR(fp->f_inode->i_mode)) {
+ filp_close(fp, 0);
+ mutex_unlock(&g_tf_lock);
+ pr_err("db_root: not a directory: %s\n", db_root_stage);
+ return -EINVAL;
+ }
+ filp_close(fp, 0);
+
+ strncpy(db_root, db_root_stage, read_bytes);
+
+ mutex_unlock(&g_tf_lock);
+
+ return read_bytes;
+}
+
+CONFIGFS_ATTR(target_core_item_, dbroot);
+
static struct target_fabric_configfs *target_core_get_fabric(
const char *name)
{
@@ -239,6 +300,7 @@ static struct configfs_group_operations target_core_fabric_group_ops = {
*/
static struct configfs_attribute *target_core_fabric_item_attrs[] = {
&target_core_item_attr_version,
+ &target_core_item_attr_dbroot,
NULL,
};
diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h
index 86b4a83..fc91e85 100644
--- a/drivers/target/target_core_internal.h
+++ b/drivers/target/target_core_internal.h
@@ -155,4 +155,10 @@ void target_stat_setup_mappedlun_default_groups(struct se_lun_acl *);
/* target_core_xcopy.c */
extern struct se_portal_group xcopy_pt_tpg;
+/* target_core_configfs.c */
+#define DB_ROOT_LEN 4096
+#define DB_ROOT_DEFAULT "/var/target"
+
+extern char db_root[];
+
#endif /* TARGET_CORE_INTERNAL_H */