target: Don't return an error if disabling unsupported features
If an attribute is present (but not yet supported) it should be OK
to write 0 (a no-op) to the attribute.
This is an issue because userspace should be able to save and restore all
set attribute values without error.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index e2be1f5..9b86394 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -954,8 +954,12 @@
return -EINVAL;
}
- pr_err("dpo_emulated not supported\n");
- return -EINVAL;
+ if (flag) {
+ pr_err("dpo_emulated not supported\n");
+ return -EINVAL;
+ }
+
+ return 0;
}
int se_dev_set_emulate_fua_write(struct se_device *dev, int flag)
@@ -965,7 +969,7 @@
return -EINVAL;
}
- if (dev->transport->fua_write_emulated == 0) {
+ if (flag && dev->transport->fua_write_emulated == 0) {
pr_err("fua_write_emulated not supported\n");
return -EINVAL;
}
@@ -982,8 +986,12 @@
return -EINVAL;
}
- pr_err("ua read emulated not supported\n");
- return -EINVAL;
+ if (flag) {
+ pr_err("ua read emulated not supported\n");
+ return -EINVAL;
+ }
+
+ return 0;
}
int se_dev_set_emulate_write_cache(struct se_device *dev, int flag)
@@ -992,7 +1000,7 @@
pr_err("Illegal value %d\n", flag);
return -EINVAL;
}
- if (dev->transport->write_cache_emulated == 0) {
+ if (flag && dev->transport->write_cache_emulated == 0) {
pr_err("write_cache_emulated not supported\n");
return -EINVAL;
}
@@ -1053,7 +1061,7 @@
* We expect this value to be non-zero when generic Block Layer
* Discard supported is detected iblock_create_virtdevice().
*/
- if (!dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count) {
+ if (flag && !dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count) {
pr_err("Generic Block Discard not supported\n");
return -ENOSYS;
}
@@ -1074,7 +1082,7 @@
* We expect this value to be non-zero when generic Block Layer
* Discard supported is detected iblock_create_virtdevice().
*/
- if (!dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count) {
+ if (flag && !dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count) {
pr_err("Generic Block Discard not supported\n");
return -ENOSYS;
}