drbd: factored tl_restart() out of tl_clear().
If IO was frozen for a temporal network outage, resend the
content of the transfer-log into the newly established connection.
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_int.h b/drivers/block/drbd/drbd_int.h
index 11b7c6f..bef9138 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -1138,6 +1138,8 @@
extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
unsigned int set_size);
extern void tl_clear(struct drbd_conf *mdev);
+enum drbd_req_event;
+extern void tl_restart(struct drbd_conf *mdev, enum drbd_req_event what);
extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *);
extern void drbd_free_sock(struct drbd_conf *mdev);
extern int drbd_send(struct drbd_conf *mdev, struct socket *sock,
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index a86e6f1..a8a0341 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -333,6 +333,77 @@
drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
}
+/**
+ * _tl_restart() - Walks the transfer log, and applies an action to all requests
+ * @mdev: DRBD device.
+ * @what: The action/event to perform with all request objects
+ *
+ * @what might be one of connection_lost_while_pending, resend, fail_frozen_disk_io,
+ * restart_frozen_disk_io.
+ */
+static void _tl_restart(struct drbd_conf *mdev, enum drbd_req_event what)
+{
+ struct drbd_tl_epoch *b, *tmp, **pn;
+ struct list_head *le, *tle;
+ struct drbd_request *req;
+ int rv, n_writes, n_reads;
+
+ b = mdev->oldest_tle;
+ pn = &mdev->oldest_tle;
+ while (b) {
+ n_writes = 0;
+ n_reads = 0;
+ list_for_each_safe(le, tle, &b->requests) {
+ req = list_entry(le, struct drbd_request, tl_requests);
+ rv = _req_mod(req, what);
+
+ n_writes += (rv & MR_WRITE) >> MR_WRITE_SHIFT;
+ n_reads += (rv & MR_READ) >> MR_READ_SHIFT;
+ }
+ tmp = b->next;
+
+ if (n_writes + n_reads) {
+ if (what == resend) {
+ b->n_writes = n_writes;
+ if (b->w.cb == NULL) {
+ b->w.cb = w_send_barrier;
+ inc_ap_pending(mdev);
+ set_bit(CREATE_BARRIER, &mdev->flags);
+ }
+
+ drbd_queue_work(&mdev->data.work, &b->w);
+ }
+ pn = &b->next;
+ } else {
+ /* there could still be requests on that ring list,
+ * in case local io is still pending */
+ list_del(&b->requests);
+
+ /* dec_ap_pending corresponding to queue_barrier.
+ * the newest barrier may not have been queued yet,
+ * in which case w.cb is still NULL. */
+ if (b->w.cb != NULL)
+ dec_ap_pending(mdev);
+
+ if (b == mdev->newest_tle) {
+ /* recycle, but reinit! */
+ D_ASSERT(tmp == NULL);
+ INIT_LIST_HEAD(&b->requests);
+ INIT_LIST_HEAD(&b->w.list);
+ b->w.cb = NULL;
+ b->br_number = net_random();
+ b->n_writes = 0;
+
+ *pn = b;
+ break;
+ }
+ *pn = tmp;
+ kfree(b);
+ }
+ b = tmp;
+ }
+}
+
/**
* tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
@@ -344,48 +415,12 @@
*/
void tl_clear(struct drbd_conf *mdev)
{
- struct drbd_tl_epoch *b, *tmp;
struct list_head *le, *tle;
struct drbd_request *r;
- int new_initial_bnr = net_random();
spin_lock_irq(&mdev->req_lock);
- b = mdev->oldest_tle;
- while (b) {
- list_for_each_safe(le, tle, &b->requests) {
- r = list_entry(le, struct drbd_request, tl_requests);
- /* It would be nice to complete outside of spinlock.
- * But this is easier for now. */
- _req_mod(r, connection_lost_while_pending);
- }
- tmp = b->next;
-
- /* there could still be requests on that ring list,
- * in case local io is still pending */
- list_del(&b->requests);
-
- /* dec_ap_pending corresponding to queue_barrier.
- * the newest barrier may not have been queued yet,
- * in which case w.cb is still NULL. */
- if (b->w.cb != NULL)
- dec_ap_pending(mdev);
-
- if (b == mdev->newest_tle) {
- /* recycle, but reinit! */
- D_ASSERT(tmp == NULL);
- INIT_LIST_HEAD(&b->requests);
- INIT_LIST_HEAD(&b->w.list);
- b->w.cb = NULL;
- b->br_number = new_initial_bnr;
- b->n_writes = 0;
-
- mdev->oldest_tle = b;
- break;
- }
- kfree(b);
- b = tmp;
- }
+ _tl_restart(mdev, connection_lost_while_pending);
/* we expect this list to be empty. */
D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
@@ -406,6 +441,13 @@
spin_unlock_irq(&mdev->req_lock);
}
+void tl_restart(struct drbd_conf *mdev, enum drbd_req_event what)
+{
+ spin_lock_irq(&mdev->req_lock);
+ _tl_restart(mdev, what);
+ spin_unlock_irq(&mdev->req_lock);
+}
+
/**
* cl_wide_st_chg() - TRUE if the state change is a cluster wide one
* @mdev: DRBD device.
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 88a5e1f..8daa920 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -776,9 +776,6 @@
D_ASSERT(!mdev->data.socket);
- if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags))
- dev_err(DEV, "CREATE_BARRIER flag was set in drbd_connect - now cleared!\n");
-
if (drbd_request_state(mdev, NS(conn, C_WF_CONNECTION)) < SS_SUCCESS)
return -2;
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index d9df1a1..39c2cc3 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -634,6 +634,20 @@
/* else: done by handed_over_to_network */
break;
+ case resend:
+ /* If RQ_NET_OK is already set, we got a P_WRITE_ACK or P_RECV_ACK
+ before the connection loss; only P_BARRIER_ACK was missing.
+ Trowing them out of the TL here by pretending we got a BARRIER_ACK
+ TODO: Either resync them, or ensure peer was not rebooted. */
+ if (!(req->rq_state & RQ_NET_OK)) {
+ if (req->w.cb) {
+ drbd_queue_work(&mdev->data.work, &req->w);
+ rv = req->rq_state & RQ_WRITE ? MR_WRITE : MR_READ;
+ }
+ break;
+ }
+ /* else, fall through to barrier_acked */
+
case barrier_acked:
if (!(req->rq_state & RQ_WRITE))
break;
diff --git a/drivers/block/drbd/drbd_req.h b/drivers/block/drbd/drbd_req.h
index db37c6e..1bcb855 100644
--- a/drivers/block/drbd/drbd_req.h
+++ b/drivers/block/drbd/drbd_req.h
@@ -104,6 +104,7 @@
read_ahead_completed_with_error,
write_completed_with_error,
completed_ok,
+ resend,
nothing, /* for tracing only */
};
@@ -206,6 +207,13 @@
#define RQ_WRITE (1UL << __RQ_WRITE)
+/* For waking up the frozen transfer log mod_req() has to return if the request
+ should be counted in the epoch object*/
+#define MR_WRITE_SHIFT 0
+#define MR_WRITE (1 << MR_WRITE_SHIFT)
+#define MR_READ_SHIFT 1
+#define MR_READ (1 << MR_READ_SHIFT)
+
/* epoch entries */
static inline
struct hlist_head *ee_hash_slot(struct drbd_conf *mdev, sector_t sector)