drbd: Starting with protocol 96 we can allow app-IO while receiving the bitmap
* C_STARTING_SYNC_S, C_STARTING_SYNC_T In these states the bitmap gets
written to disk. Locking out of app-IO is done by using the
drbd_queue_bitmap_io() and drbd_bitmap_io() functions these days.
It is no longer necessary to lock out app-IO based on the connection
state.
App-IO that may come in after the BITMAP_IO flag got cleared before the
state transition to C_SYNC_(SOURCE|TARGET) does not get mirrored, sets
a bit in the local bitmap, that is already set, therefore changes nothing.
* C_WF_BITMAP_S In this state we send updates (P_OUT_OF_SYNC packets).
With that we make sure they have the same number of bits when going
into the C_SYNC_(SOURCE|TARGET) connection state.
* C_UNCONNECTED: The receiver starts, no need to lock out IO.
* C_DISCONNECTING: in drbd_disconnect() we had a wait_event()
to wait until ap_bio_cnt reaches 0. Removed that.
* C_TIMEOUT, C_BROKEN_PIPE, C_NETWORK_FAILURE
C_PROTOCOL_ERROR, C_TEAR_DOWN: Same as C_DISCONNECTING
* C_WF_REPORT_PARAMS: IO still possible since that is still
like C_WF_CONNECTION.
And we do not need to send barriers in C_WF_BITMAP_S connection state.
Allow concurrent accesses to the bitmap when receiving the bitmap.
Everything gets ORed anyways.
A drbd_free_tl_hash() is in after_state_chg_work(). At that point
all the work items of the last connections must have been processed.
Introduced a call to drbd_free_tl_hash() into drbd_free_mdev()
for paranoia reasons.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 0630a2e..f4aba9f 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -3468,9 +3468,7 @@
int ok = FALSE;
struct p_header80 *h = &mdev->data.rbuf.header.h80;
- wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
-
- drbd_bm_lock(mdev, "receive bitmap");
+ /* drbd_bm_lock(mdev, "receive bitmap"); By intention no bm_lock */
/* maybe we should use some per thread scratch page,
* and allocate that during initial device creation? */
@@ -3542,7 +3540,7 @@
ok = TRUE;
out:
- drbd_bm_unlock(mdev);
+ /* drbd_bm_unlock(mdev); by intention no lock */
if (ok && mdev->state.conn == C_WF_BITMAP_S)
drbd_start_resync(mdev, C_SYNC_SOURCE);
free_page((unsigned long) buffer);
@@ -3804,13 +3802,6 @@
if (os.conn == C_DISCONNECTING) {
wait_event(mdev->net_cnt_wait, atomic_read(&mdev->net_cnt) == 0);
- if (!is_susp(mdev->state)) {
- /* we must not free the tl_hash
- * while application io is still on the fly */
- wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
- drbd_free_tl_hash(mdev);
- }
-
crypto_free_hash(mdev->cram_hmac_tfm);
mdev->cram_hmac_tfm = NULL;