aboutsummaryrefslogtreecommitdiff
path: root/drivers/block/drbd/drbd_receiver.c
diff options
context:
space:
mode:
authorPhilipp Reisner <philipp.reisner@linbit.com>2011-05-03 16:47:02 +0200
committerPhilipp Reisner <philipp.reisner@linbit.com>2012-11-08 16:55:44 +0100
commit813472ced7fac734157fe5be1137ce2bac942902 (patch)
treef6cfd59aadc28d460f76ad173deb123f10f3b974 /drivers/block/drbd/drbd_receiver.c
parentd589a21e5d9099a6351862ae6a7f4ae5ec4103d4 (diff)
downloadvexpress-lsk-813472ced7fac734157fe5be1137ce2bac942902.tar.gz
drbd: RCU for rs_plan_s
This removes the issue with using peer_seq_lock out of different contexts. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd/drbd_receiver.c')
-rw-r--r--drivers/block/drbd/drbd_receiver.c71
1 files changed, 44 insertions, 27 deletions
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 19b421f44ff..83d39859a9f 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -3157,9 +3157,9 @@ static int receive_SyncParam(struct drbd_tconn *tconn, struct packet_info *pi)
struct crypto_hash *verify_tfm = NULL;
struct crypto_hash *csums_tfm = NULL;
struct net_conf *old_net_conf, *new_net_conf = NULL;
- struct disk_conf *old_disk_conf, *new_disk_conf = NULL;
+ struct disk_conf *old_disk_conf = NULL, *new_disk_conf = NULL;
const int apv = tconn->agreed_pro_version;
- struct fifo_buffer *rs_plan_s = NULL;
+ struct fifo_buffer *old_plan = NULL, *new_plan = NULL;
int fifo_size = 0;
int err;
@@ -3200,18 +3200,22 @@ static int receive_SyncParam(struct drbd_tconn *tconn, struct packet_info *pi)
if (err)
return err;
- new_disk_conf = kzalloc(sizeof(struct disk_conf), GFP_KERNEL);
- if (!new_disk_conf) {
- dev_err(DEV, "Allocation of new disk_conf failed\n");
- return -ENOMEM;
- }
-
mutex_lock(&mdev->tconn->conf_update);
old_net_conf = mdev->tconn->net_conf;
- old_disk_conf = mdev->ldev->disk_conf;
- *new_disk_conf = *old_disk_conf;
+ if (get_ldev(mdev)) {
+ new_disk_conf = kzalloc(sizeof(struct disk_conf), GFP_KERNEL);
+ if (!new_disk_conf) {
+ put_ldev(mdev);
+ mutex_unlock(&mdev->tconn->conf_update);
+ dev_err(DEV, "Allocation of new disk_conf failed\n");
+ return -ENOMEM;
+ }
- new_disk_conf->resync_rate = be32_to_cpu(p->rate);
+ old_disk_conf = mdev->ldev->disk_conf;
+ *new_disk_conf = *old_disk_conf;
+
+ new_disk_conf->resync_rate = be32_to_cpu(p->rate);
+ }
if (apv >= 88) {
if (apv == 88) {
@@ -3219,15 +3223,13 @@ static int receive_SyncParam(struct drbd_tconn *tconn, struct packet_info *pi)
dev_err(DEV, "verify-alg too long, "
"peer wants %u, accepting only %u byte\n",
data_size, SHARED_SECRET_MAX);
- mutex_unlock(&mdev->tconn->conf_update);
- return -EIO;
+ err = -EIO;
+ goto reconnect;
}
err = drbd_recv_all(mdev->tconn, p->verify_alg, data_size);
- if (err) {
- mutex_unlock(&mdev->tconn->conf_update);
- return err;
- }
+ if (err)
+ goto reconnect;
/* we expect NUL terminated string */
/* but just in case someone tries to be evil */
D_ASSERT(p->verify_alg[data_size-1] == 0);
@@ -3270,7 +3272,7 @@ static int receive_SyncParam(struct drbd_tconn *tconn, struct packet_info *pi)
}
}
- if (apv > 94) {
+ if (apv > 94 && new_disk_conf) {
new_disk_conf->c_plan_ahead = be32_to_cpu(p->c_plan_ahead);
new_disk_conf->c_delay_target = be32_to_cpu(p->c_delay_target);
new_disk_conf->c_fill_target = be32_to_cpu(p->c_fill_target);
@@ -3278,8 +3280,8 @@ static int receive_SyncParam(struct drbd_tconn *tconn, struct packet_info *pi)
fifo_size = (new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ;
if (fifo_size != mdev->rs_plan_s->size) {
- rs_plan_s = fifo_alloc(fifo_size);
- if (!rs_plan_s) {
+ new_plan = fifo_alloc(fifo_size);
+ if (!new_plan) {
dev_err(DEV, "kmalloc of fifo_buffer failed");
put_ldev(mdev);
goto disconnect;
@@ -3314,24 +3316,39 @@ static int receive_SyncParam(struct drbd_tconn *tconn, struct packet_info *pi)
}
}
- rcu_assign_pointer(mdev->ldev->disk_conf, new_disk_conf);
- spin_lock(&mdev->peer_seq_lock);
- if (rs_plan_s) {
- kfree(mdev->rs_plan_s);
- mdev->rs_plan_s = rs_plan_s;
+ if (new_disk_conf) {
+ rcu_assign_pointer(mdev->ldev->disk_conf, new_disk_conf);
+ put_ldev(mdev);
+ }
+
+ if (new_plan) {
+ old_plan = mdev->rs_plan_s;
+ rcu_assign_pointer(mdev->rs_plan_s, new_plan);
}
- spin_unlock(&mdev->peer_seq_lock);
mutex_unlock(&mdev->tconn->conf_update);
synchronize_rcu();
if (new_net_conf)
kfree(old_net_conf);
kfree(old_disk_conf);
+ kfree(old_plan);
return 0;
+reconnect:
+ if (new_disk_conf) {
+ put_ldev(mdev);
+ kfree(new_disk_conf);
+ }
+ mutex_unlock(&mdev->tconn->conf_update);
+ return -EIO;
+
disconnect:
- kfree(rs_plan_s);
+ kfree(new_plan);
+ if (new_disk_conf) {
+ put_ldev(mdev);
+ kfree(new_disk_conf);
+ }
mutex_unlock(&mdev->tconn->conf_update);
/* just for completeness: actually not needed,
* as this is not reached if csums_tfm was ok. */