drbd: Enable QUEUE_FLAG_DISCARD only if the peer can recieve P_TRIM
Allow the user of REQ_DISCARD.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 9640b64..3fa3b78 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -46,9 +46,10 @@
#include "drbd_int.h"
#include "drbd_protocol.h"
#include "drbd_req.h"
-
#include "drbd_vli.h"
+#define PRO_FEATURES (FF_TRIM)
+
struct packet_info {
enum drbd_packet cmd;
unsigned int size;
@@ -3705,6 +3706,13 @@
put_ldev(device);
}
+ device->peer_max_bio_size = be32_to_cpu(p->max_bio_size);
+ drbd_reconsider_max_bio_size(device);
+ /* Leave drbd_reconsider_max_bio_size() before drbd_determine_dev_size().
+ In case we cleared the QUEUE_FLAG_DISCARD from our queue in
+ drbd_reconsider_max_bio_size(), we can be sure that after
+ drbd_determine_dev_size() no REQ_DISCARDs are in the queue. */
+
ddsf = be16_to_cpu(p->dds_flags);
if (get_ldev(device)) {
dd = drbd_determine_dev_size(device, ddsf, NULL);
@@ -3717,9 +3725,6 @@
drbd_set_my_capacity(device, p_size);
}
- device->peer_max_bio_size = be32_to_cpu(p->max_bio_size);
- drbd_reconsider_max_bio_size(device);
-
if (get_ldev(device)) {
if (device->ldev->known_size != drbd_get_capacity(device->ldev->backing_bdev)) {
device->ldev->known_size = drbd_get_capacity(device->ldev->backing_bdev);
@@ -4688,6 +4693,7 @@
memset(p, 0, sizeof(*p));
p->protocol_min = cpu_to_be32(PRO_VERSION_MIN);
p->protocol_max = cpu_to_be32(PRO_VERSION_MAX);
+ p->feature_flags = cpu_to_be32(PRO_FEATURES);
return conn_send_command(connection, sock, P_CONNECTION_FEATURES, sizeof(*p), NULL, 0);
}
@@ -4741,10 +4747,14 @@
goto incompat;
connection->agreed_pro_version = min_t(int, PRO_VERSION_MAX, p->protocol_max);
+ connection->agreed_features = PRO_FEATURES & be32_to_cpu(p->feature_flags);
drbd_info(connection, "Handshake successful: "
"Agreed network protocol version %d\n", connection->agreed_pro_version);
+ drbd_info(connection, "Agreed to%ssupport TRIM on protocol level\n",
+ connection->agreed_features & FF_TRIM ? " " : " not ");
+
return 1;
incompat: