dm thin: correct comments
Remove documentation for unimplemented 'trim' message.
I'd planned a 'trim' target message for shrinking thin devices, but
this is better handled via the discard ioctl.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/Documentation/device-mapper/thin-provisioning.txt b/Documentation/device-mapper/thin-provisioning.txt
index 1ff044d..da50347 100644
--- a/Documentation/device-mapper/thin-provisioning.txt
+++ b/Documentation/device-mapper/thin-provisioning.txt
@@ -237,16 +237,6 @@
Deletes a thin device. Irreversible.
- trim <dev id> <new size in sectors>
-
- Delete mappings from the end of a thin device. Irreversible.
- You might want to use this if you're reducing the size of
- your thinly-provisioned device. In many cases, due to the
- sharing of blocks between devices, it is not possible to
- determine in advance how much space 'trim' will release. (In
- future a userspace tool might be able to perform this
- calculation.)
-
set_transaction_id <current id> <new id>
Userland volume managers, such as LVM, need a way to
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index da2f021..1791134 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -72,7 +72,7 @@
* missed out if the io covers the block. (schedule_copy).
*
* iv) insert the new mapping into the origin's btree
- * (process_prepared_mappings). This act of inserting breaks some
+ * (process_prepared_mapping). This act of inserting breaks some
* sharing of btree nodes between the two devices. Breaking sharing only
* effects the btree of that specific device. Btrees for the other
* devices that share the block never change. The btree for the origin