drbd: Use new header layout
The new header layout will only be used if the peer supports
it of course.
For the first packet and the handshake packet the old (h80)
layout is used for compatibility 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_main.c b/drivers/block/drbd/drbd_main.c
index 55ce48e..f8cb15c 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -1820,12 +1820,36 @@
}
#endif
+static void prepare_header80(struct drbd_conf *mdev, struct p_header80 *h,
+ enum drbd_packets cmd, int size)
+{
+ h->magic = cpu_to_be32(DRBD_MAGIC);
+ h->command = cpu_to_be16(cmd);
+ h->length = cpu_to_be16(size);
+}
+
+static void prepare_header95(struct drbd_conf *mdev, struct p_header95 *h,
+ enum drbd_packets cmd, int size)
+{
+ h->magic = cpu_to_be16(DRBD_MAGIC_BIG);
+ h->command = cpu_to_be16(cmd);
+ h->length = cpu_to_be32(size);
+}
+
+static void prepare_header(struct drbd_conf *mdev, struct p_header *h,
+ enum drbd_packets cmd, int size)
+{
+ if (mdev->tconn->agreed_pro_version >= 100 || size > DRBD_MAX_SIZE_H80_PACKET)
+ prepare_header95(mdev, &h->h95, cmd, size);
+ else
+ prepare_header80(mdev, &h->h80, cmd, size);
+}
+
/* the appropriate socket mutex must be held already */
int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
- enum drbd_packets cmd, struct p_header *hg,
+ enum drbd_packets cmd, struct p_header *h,
size_t size, unsigned msg_flags)
{
- struct p_header80 *h = (struct p_header80 *)hg;
int sent, ok;
if (!expect(h))
@@ -1833,9 +1857,7 @@
if (!expect(size))
return false;
- h->magic = cpu_to_be32(DRBD_MAGIC);
- h->command = cpu_to_be16(cmd);
- h->length = cpu_to_be16(size-sizeof(struct p_header80));
+ prepare_header(mdev, h, cmd, size - sizeof(struct p_header));
sent = drbd_send(mdev, sock, h, size, msg_flags);
@@ -1878,12 +1900,10 @@
int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
size_t size)
{
- struct p_header80 h;
+ struct p_header h;
int ok;
- h.magic = cpu_to_be32(DRBD_MAGIC);
- h.command = cpu_to_be16(cmd);
- h.length = cpu_to_be16(size);
+ prepare_header(mdev, &h, cmd, size);
if (!drbd_get_data_sock(mdev))
return 0;
@@ -2456,14 +2476,11 @@
int ok;
struct p_block_req p;
+ prepare_header(mdev, &p.head, cmd, sizeof(p) - sizeof(struct p_header) + digest_size);
p.sector = cpu_to_be64(sector);
p.block_id = ID_SYNCER /* unused */;
p.blksize = cpu_to_be32(size);
- p.head.h80.magic = cpu_to_be32(DRBD_MAGIC);
- p.head.h80.command = cpu_to_be16(cmd);
- p.head.h80.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header80) + digest_size);
-
mutex_lock(&mdev->tconn->data.mutex);
ok = (sizeof(p) == drbd_send(mdev, mdev->tconn->data.socket, &p, sizeof(p), 0));
@@ -2663,22 +2680,10 @@
dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
- if (req->i.size <= DRBD_MAX_SIZE_H80_PACKET) {
- p.head.h80.magic = cpu_to_be32(DRBD_MAGIC);
- p.head.h80.command = cpu_to_be16(P_DATA);
- p.head.h80.length =
- cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->i.size);
- } else {
- p.head.h95.magic = cpu_to_be16(DRBD_MAGIC_BIG);
- p.head.h95.command = cpu_to_be16(P_DATA);
- p.head.h95.length =
- cpu_to_be32(sizeof(p) - sizeof(struct p_header) + dgs + req->i.size);
- }
-
+ prepare_header(mdev, &p.head, P_DATA, sizeof(p) - sizeof(struct p_header) + dgs + req->i.size);
p.sector = cpu_to_be64(req->i.sector);
p.block_id = (unsigned long)req;
- p.seq_num = cpu_to_be32(req->seq_num =
- atomic_add_return(1, &mdev->packet_seq));
+ p.seq_num = cpu_to_be32(req->seq_num = atomic_add_return(1, &mdev->packet_seq));
dp_flags = bio_flags_to_wire(mdev, req->master_bio->bi_rw);
@@ -2748,18 +2753,7 @@
dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
- if (e->i.size <= DRBD_MAX_SIZE_H80_PACKET) {
- p.head.h80.magic = cpu_to_be32(DRBD_MAGIC);
- p.head.h80.command = cpu_to_be16(cmd);
- p.head.h80.length =
- cpu_to_be16(sizeof(p) - sizeof(struct p_header80) + dgs + e->i.size);
- } else {
- p.head.h95.magic = cpu_to_be16(DRBD_MAGIC_BIG);
- p.head.h95.command = cpu_to_be16(cmd);
- p.head.h95.length =
- cpu_to_be32(sizeof(p) - sizeof(struct p_header80) + dgs + e->i.size);
- }
-
+ prepare_header(mdev, &p.head, cmd, sizeof(p) - sizeof(struct p_header80) + dgs + e->i.size);
p.sector = cpu_to_be64(e->i.sector);
p.block_id = e->block_id;
/* p.seq_num = 0; No sequence numbers here.. */
@@ -3028,7 +3022,7 @@
drbd_thread_init(mdev, &mdev->tconn->worker, drbd_worker);
drbd_thread_init(mdev, &mdev->tconn->asender, drbd_asender);
- mdev->tconn->agreed_pro_version = PRO_VERSION_MAX;
+ /* mdev->tconn->agreed_pro_version gets initialized in drbd_connect() */
mdev->write_ordering = WO_bdev_flush;
mdev->resync_wenr = LC_FREE;
mdev->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
@@ -3506,12 +3500,8 @@
{
int err;
- if (sizeof(struct p_handshake) != 80) {
- printk(KERN_ERR
- "drbd: never change the size or layout "
- "of the HandShake packet.\n");
- return -EINVAL;
- }
+ BUILD_BUG_ON(sizeof(struct p_header80) != sizeof(struct p_header95));
+ BUILD_BUG_ON(sizeof(struct p_handshake) != 80);
if (minor_count < DRBD_MINOR_COUNT_MIN || minor_count > DRBD_MINOR_COUNT_MAX) {
printk(KERN_ERR
