drbd: receiving of big packets, for payloads between 64kByte and 4GByte
authorPhilipp Reisner <philipp.reisner@linbit.com>
Fri, 20 Aug 2010 12:35:10 +0000 (14:35 +0200)
committerPhilipp Reisner <philipp.reisner@linbit.com>
Thu, 14 Oct 2010 16:38:24 +0000 (18:38 +0200)
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
drivers/block/drbd/drbd_int.h
drivers/block/drbd/drbd_receiver.c

index 3f10efc2ac147485ae6a115a5b2ec183941050f4..db7e65531afa4ad6138c501b24655b3e167ba15e 100644 (file)
@@ -626,7 +626,7 @@ DCBP_set_pad_bits(struct p_compressed_bm *p, int n)
 #endif
 
 union p_polymorph {
-        struct p_header80        header;
+        union p_header           header;
         struct p_handshake       handshake;
         struct p_data            data;
         struct p_block_ack       block_ack;
@@ -641,6 +641,8 @@ union p_polymorph {
         struct p_req_state       req_state;
         struct p_req_state_reply req_state_reply;
         struct p_block_req       block_req;
+       struct p_delay_probe93   delay_probe93;
+       struct p_rs_uuid         rs_uuid;
 } __packed;
 
 /**********************************************************************/
index 9b3321e2c3cd9e54b204fd80cab53165f78a8188..fe308644a63ca9a004f58b328def9669668136bd 100644 (file)
@@ -720,14 +720,14 @@ out:
 static int drbd_send_fp(struct drbd_conf *mdev,
        struct socket *sock, enum drbd_packets cmd)
 {
-       struct p_header80 *h = (struct p_header80 *) &mdev->data.sbuf.header;
+       struct p_header80 *h = &mdev->data.sbuf.header.h80;
 
        return _drbd_send_cmd(mdev, sock, cmd, h, sizeof(*h), 0);
 }
 
 static enum drbd_packets drbd_recv_fp(struct drbd_conf *mdev, struct socket *sock)
 {
-       struct p_header80 *h = (struct p_header80 *) &mdev->data.sbuf.header;
+       struct p_header80 *h = &mdev->data.rbuf.header.h80;
        int rr;
 
        rr = drbd_recv_short(mdev, sock, h, sizeof(*h), 0);
@@ -944,22 +944,27 @@ out_release_sockets:
        return -1;
 }
 
-static int drbd_recv_header(struct drbd_conf *mdev, struct p_header80 *h)
+static int drbd_recv_header(struct drbd_conf *mdev, enum drbd_packets *cmd, unsigned int *packet_size)
 {
+       union p_header *h = &mdev->data.rbuf.header;
        int r;
 
        r = drbd_recv(mdev, h, sizeof(*h));
-
        if (unlikely(r != sizeof(*h))) {
                dev_err(DEV, "short read expecting header on sock: r=%d\n", r);
                return FALSE;
-       };
-       h->command = be16_to_cpu(h->command);
-       h->length  = be16_to_cpu(h->length);
-       if (unlikely(h->magic != BE_DRBD_MAGIC)) {
+       }
+
+       if (likely(h->h80.magic == BE_DRBD_MAGIC)) {
+               *cmd = be16_to_cpu(h->h80.command);
+               *packet_size = be16_to_cpu(h->h80.length);
+       } else if (h->h95.magic == BE_DRBD_MAGIC_BIG) {
+               *cmd = be16_to_cpu(h->h95.command);
+               *packet_size = be32_to_cpu(h->h95.length);
+       } else {
                dev_err(DEV, "magic?? on data m: 0x%lx c: %d l: %d\n",
-                   (long)be32_to_cpu(h->magic),
-                   h->command, h->length);
+                   (long)be32_to_cpu(h->h80.magic),
+                   h->h80.command, h->h80.length);
                return FALSE;
        }
        mdev->last_received = jiffies;
@@ -1266,17 +1271,12 @@ int w_e_reissue(struct drbd_conf *mdev, struct drbd_work *w, int cancel) __relea
        return 1;
 }
 
-static int receive_Barrier(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_Barrier(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
        int rv, issue_flush;
-       struct p_barrier *p = (struct p_barrier *)h;
+       struct p_barrier *p = &mdev->data.rbuf.barrier;
        struct drbd_epoch *epoch;
 
-       ERR_IF(h->length != (sizeof(*p)-sizeof(*h))) return FALSE;
-
-       rv = drbd_recv(mdev, h->payload, h->length);
-       ERR_IF(rv != h->length) return FALSE;
-
        inc_unacked(mdev);
 
        if (mdev->net_conf->wire_protocol != DRBD_PROT_C)
@@ -1570,21 +1570,12 @@ fail:
        return FALSE;
 }
 
-static int receive_DataReply(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_DataReply(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
        struct drbd_request *req;
        sector_t sector;
-       unsigned int header_size, data_size;
        int ok;
-       struct p_data *p = (struct p_data *)h;
-
-       header_size = sizeof(*p) - sizeof(*h);
-       data_size   = h->length  - header_size;
-
-       ERR_IF(data_size == 0) return FALSE;
-
-       if (drbd_recv(mdev, h->payload, header_size) != header_size)
-               return FALSE;
+       struct p_data *p = &mdev->data.rbuf.data;
 
        sector = be64_to_cpu(p->sector);
 
@@ -1610,20 +1601,11 @@ static int receive_DataReply(struct drbd_conf *mdev, struct p_header80 *h)
        return ok;
 }
 
-static int receive_RSDataReply(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_RSDataReply(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
        sector_t sector;
-       unsigned int header_size, data_size;
        int ok;
-       struct p_data *p = (struct p_data *)h;
-
-       header_size = sizeof(*p) - sizeof(*h);
-       data_size   = h->length  - header_size;
-
-       ERR_IF(data_size == 0) return FALSE;
-
-       if (drbd_recv(mdev, h->payload, header_size) != header_size)
-               return FALSE;
+       struct p_data *p = &mdev->data.rbuf.data;
 
        sector = be64_to_cpu(p->sector);
        D_ASSERT(p->block_id == ID_SYNCER);
@@ -1767,23 +1749,14 @@ static int drbd_wait_peer_seq(struct drbd_conf *mdev, const u32 packet_seq)
 }
 
 /* mirrored write */
-static int receive_Data(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_Data(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
        sector_t sector;
        struct drbd_epoch_entry *e;
-       struct p_data *p = (struct p_data *)h;
-       int header_size, data_size;
+       struct p_data *p = &mdev->data.rbuf.data;
        int rw = WRITE;
        u32 dp_flags;
 
-       header_size = sizeof(*p) - sizeof(*h);
-       data_size   = h->length  - header_size;
-
-       ERR_IF(data_size == 0) return FALSE;
-
-       if (drbd_recv(mdev, h->payload, header_size) != header_size)
-               return FALSE;
-
        if (!get_ldev(mdev)) {
                if (__ratelimit(&drbd_ratelimit_state))
                        dev_err(DEV, "Can not write mirrored data block "
@@ -2066,20 +2039,15 @@ int drbd_rs_should_slow_down(struct drbd_conf *mdev)
 }
 
 
-static int receive_DataRequest(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_DataRequest(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int digest_size)
 {
        sector_t sector;
        const sector_t capacity = drbd_get_capacity(mdev->this_bdev);
        struct drbd_epoch_entry *e;
        struct digest_info *di = NULL;
-       struct p_block_req *p = (struct p_block_req *)h;
-       const int brps = sizeof(*p)-sizeof(*h);
-       int size, digest_size;
+       int size;
        unsigned int fault_type;
-
-
-       if (drbd_recv(mdev, h->payload, brps) != brps)
-               return FALSE;
+       struct p_block_req *p = &mdev->data.rbuf.block_req;
 
        sector = be64_to_cpu(p->sector);
        size   = be32_to_cpu(p->blksize);
@@ -2099,9 +2067,9 @@ static int receive_DataRequest(struct drbd_conf *mdev, struct p_header80 *h)
                if (__ratelimit(&drbd_ratelimit_state))
                        dev_err(DEV, "Can not satisfy peer's read request, "
                            "no local data.\n");
-               drbd_send_ack_rp(mdev, h->command == P_DATA_REQUEST ? P_NEG_DREPLY :
+               drbd_send_ack_rp(mdev, cmd == P_DATA_REQUEST ? P_NEG_DREPLY :
                                 P_NEG_RS_DREPLY , p);
-               return drbd_drain_block(mdev, h->length - brps);
+               return TRUE;
        }
 
        /* GFP_NOIO, because we must not cause arbitrary write-out: in a DRBD
@@ -2113,7 +2081,7 @@ static int receive_DataRequest(struct drbd_conf *mdev, struct p_header80 *h)
                return FALSE;
        }
 
-       switch (h->command) {
+       switch (cmd) {
        case P_DATA_REQUEST:
                e->w.cb = w_e_end_data_req;
                fault_type = DRBD_FAULT_DT_RD;
@@ -2128,7 +2096,6 @@ static int receive_DataRequest(struct drbd_conf *mdev, struct p_header80 *h)
        case P_OV_REPLY:
        case P_CSUM_RS_REQUEST:
                fault_type = DRBD_FAULT_RS_RD;
-               digest_size = h->length - brps ;
                di = kmalloc(sizeof(*di) + digest_size, GFP_NOIO);
                if (!di)
                        goto out_free_e;
@@ -2142,10 +2109,10 @@ static int receive_DataRequest(struct drbd_conf *mdev, struct p_header80 *h)
                if (drbd_recv(mdev, di->digest, digest_size) != digest_size)
                        goto out_free_e;
 
-               if (h->command == P_CSUM_RS_REQUEST) {
+               if (cmd == P_CSUM_RS_REQUEST) {
                        D_ASSERT(mdev->agreed_pro_version >= 89);
                        e->w.cb = w_e_end_csum_rs_req;
-               } else if (h->command == P_OV_REPLY) {
+               } else if (cmd == P_OV_REPLY) {
                        e->w.cb = w_e_end_ov_reply;
                        dec_rs_pending(mdev);
                        /* drbd_rs_begin_io done when we sent this request,
@@ -2173,7 +2140,7 @@ static int receive_DataRequest(struct drbd_conf *mdev, struct p_header80 *h)
 
        default:
                dev_err(DEV, "unexpected command (%s) in receive_DataRequest\n",
-                   cmdname(h->command));
+                   cmdname(cmd));
                fault_type = DRBD_FAULT_MAX;
                goto out_free_e;
        }
@@ -2756,20 +2723,13 @@ static int cmp_after_sb(enum drbd_after_sb_p peer, enum drbd_after_sb_p self)
        return 1;
 }
 
-static int receive_protocol(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_protocol(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
-       struct p_protocol *p = (struct p_protocol *)h;
-       int header_size, data_size;
+       struct p_protocol *p = &mdev->data.rbuf.protocol;
        int p_proto, p_after_sb_0p, p_after_sb_1p, p_after_sb_2p;
        int p_want_lose, p_two_primaries, cf;
        char p_integrity_alg[SHARED_SECRET_MAX] = "";
 
-       header_size = sizeof(*p) - sizeof(*h);
-       data_size   = h->length  - header_size;
-
-       if (drbd_recv(mdev, h->payload, header_size) != header_size)
-               return FALSE;
-
        p_proto         = be32_to_cpu(p->protocol);
        p_after_sb_0p   = be32_to_cpu(p->after_sb_0p);
        p_after_sb_1p   = be32_to_cpu(p->after_sb_1p);
@@ -2862,10 +2822,10 @@ struct crypto_hash *drbd_crypto_alloc_digest_safe(const struct drbd_conf *mdev,
        return tfm;
 }
 
-static int receive_SyncParam(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_SyncParam(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int packet_size)
 {
        int ok = TRUE;
-       struct p_rs_param_95 *p = (struct p_rs_param_95 *)h;
+       struct p_rs_param_95 *p = &mdev->data.rbuf.rs_param_95;
        unsigned int header_size, data_size, exp_max_sz;
        struct crypto_hash *verify_tfm = NULL;
        struct crypto_hash *csums_tfm = NULL;
@@ -2879,29 +2839,29 @@ static int receive_SyncParam(struct drbd_conf *mdev, struct p_header80 *h)
                    : apv <= 94 ? sizeof(struct p_rs_param_89)
                    : /* apv >= 95 */ sizeof(struct p_rs_param_95);
 
-       if (h->length > exp_max_sz) {
+       if (packet_size > exp_max_sz) {
                dev_err(DEV, "SyncParam packet too long: received %u, expected <= %u bytes\n",
-                   h->length, exp_max_sz);
+                   packet_size, exp_max_sz);
                return FALSE;
        }
 
        if (apv <= 88) {
-               header_size = sizeof(struct p_rs_param) - sizeof(*h);
-               data_size   = h->length  - header_size;
+               header_size = sizeof(struct p_rs_param) - sizeof(struct p_header80);
+               data_size   = packet_size  - header_size;
        } else if (apv <= 94) {
-               header_size = sizeof(struct p_rs_param_89) - sizeof(*h);
-               data_size   = h->length  - header_size;
+               header_size = sizeof(struct p_rs_param_89) - sizeof(struct p_header80);
+               data_size   = packet_size  - header_size;
                D_ASSERT(data_size == 0);
        } else {
-               header_size = sizeof(struct p_rs_param_95) - sizeof(*h);
-               data_size   = h->length  - header_size;
+               header_size = sizeof(struct p_rs_param_95) - sizeof(struct p_header80);
+               data_size   = packet_size  - header_size;
                D_ASSERT(data_size == 0);
        }
 
        /* initialize verify_alg and csums_alg */
        memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
 
-       if (drbd_recv(mdev, h->payload, header_size) != header_size)
+       if (drbd_recv(mdev, &p->head.payload, header_size) != header_size)
                return FALSE;
 
        mdev->sync_conf.rate      = be32_to_cpu(p->rate);
@@ -3032,19 +2992,15 @@ static void warn_if_differ_considerably(struct drbd_conf *mdev,
                     (unsigned long long)a, (unsigned long long)b);
 }
 
-static int receive_sizes(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_sizes(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
-       struct p_sizes *p = (struct p_sizes *)h;
+       struct p_sizes *p = &mdev->data.rbuf.sizes;
        enum determine_dev_size dd = unchanged;
        unsigned int max_seg_s;
        sector_t p_size, p_usize, my_usize;
        int ldsc = 0; /* local disk size changed */
        enum dds_flags ddsf;
 
-       ERR_IF(h->length != (sizeof(*p)-sizeof(*h))) return FALSE;
-       if (drbd_recv(mdev, h->payload, h->length) != h->length)
-               return FALSE;
-
        p_size = be64_to_cpu(p->d_size);
        p_usize = be64_to_cpu(p->u_size);
 
@@ -3148,16 +3104,12 @@ static int receive_sizes(struct drbd_conf *mdev, struct p_header80 *h)
        return TRUE;
 }
 
-static int receive_uuids(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_uuids(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
-       struct p_uuids *p = (struct p_uuids *)h;
+       struct p_uuids *p = &mdev->data.rbuf.uuids;
        u64 *p_uuid;
        int i;
 
-       ERR_IF(h->length != (sizeof(*p)-sizeof(*h))) return FALSE;
-       if (drbd_recv(mdev, h->payload, h->length) != h->length)
-               return FALSE;
-
        p_uuid = kmalloc(sizeof(u64)*UI_EXTENDED_SIZE, GFP_NOIO);
 
        for (i = UI_CURRENT; i < UI_EXTENDED_SIZE; i++)
@@ -3241,16 +3193,12 @@ static union drbd_state convert_state(union drbd_state ps)
        return ms;
 }
 
-static int receive_req_state(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_req_state(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
-       struct p_req_state *p = (struct p_req_state *)h;
+       struct p_req_state *p = &mdev->data.rbuf.req_state;
        union drbd_state mask, val;
        int rv;
 
-       ERR_IF(h->length != (sizeof(*p)-sizeof(*h))) return FALSE;
-       if (drbd_recv(mdev, h->payload, h->length) != h->length)
-               return FALSE;
-
        mask.i = be32_to_cpu(p->mask);
        val.i = be32_to_cpu(p->val);
 
@@ -3271,21 +3219,15 @@ static int receive_req_state(struct drbd_conf *mdev, struct p_header80 *h)
        return TRUE;
 }
 
-static int receive_state(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_state(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
-       struct p_state *p = (struct p_state *)h;
+       struct p_state *p = &mdev->data.rbuf.state;
        enum drbd_conns nconn, oconn;
        union drbd_state ns, peer_state;
        enum drbd_disk_state real_peer_disk;
        enum chg_state_flags cs_flags;
        int rv;
 
-       ERR_IF(h->length != (sizeof(*p)-sizeof(*h)))
-               return FALSE;
-
-       if (drbd_recv(mdev, h->payload, h->length) != h->length)
-               return FALSE;
-
        peer_state.i = be32_to_cpu(p->state);
 
        real_peer_disk = peer_state.disk;
@@ -3395,9 +3337,9 @@ static int receive_state(struct drbd_conf *mdev, struct p_header80 *h)
        return TRUE;
 }
 
-static int receive_sync_uuid(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_sync_uuid(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
-       struct p_rs_uuid *p = (struct p_rs_uuid *)h;
+       struct p_rs_uuid *p = &mdev->data.rbuf.rs_uuid;
 
        wait_event(mdev->misc_wait,
                   mdev->state.conn == C_WF_SYNC_UUID ||
@@ -3406,10 +3348,6 @@ static int receive_sync_uuid(struct drbd_conf *mdev, struct p_header80 *h)
 
        /* D_ASSERT( mdev->state.conn == C_WF_SYNC_UUID ); */
 
-       ERR_IF(h->length != (sizeof(*p)-sizeof(*h))) return FALSE;
-       if (drbd_recv(mdev, h->payload, h->length) != h->length)
-               return FALSE;
-
        /* Here the _drbd_uuid_ functions are right, current should
           _not_ be rotated into the history */
        if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
@@ -3428,14 +3366,14 @@ static int receive_sync_uuid(struct drbd_conf *mdev, struct p_header80 *h)
 enum receive_bitmap_ret { OK, DONE, FAILED };
 
 static enum receive_bitmap_ret
-receive_bitmap_plain(struct drbd_conf *mdev, struct p_header80 *h,
-       unsigned long *buffer, struct bm_xfer_ctx *c)
+receive_bitmap_plain(struct drbd_conf *mdev, unsigned int data_size,
+                    unsigned long *buffer, struct bm_xfer_ctx *c)
 {
        unsigned num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
        unsigned want = num_words * sizeof(long);
 
-       if (want != h->length) {
-               dev_err(DEV, "%s:want (%u) != h->length (%u)\n", __func__, want, h->length);
+       if (want != data_size) {
+               dev_err(DEV, "%s:want (%u) != data_size (%u)\n", __func__, want, data_size);
                return FAILED;
        }
        if (want == 0)
@@ -3571,12 +3509,13 @@ void INFO_bm_xfer_stats(struct drbd_conf *mdev,
    in order to be agnostic to the 32 vs 64 bits issue.
 
    returns 0 on failure, 1 if we successfully received it. */
-static int receive_bitmap(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_bitmap(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
        struct bm_xfer_ctx c;
        void *buffer;
        enum receive_bitmap_ret ret;
        int ok = FALSE;
+       struct p_header80 *h = &mdev->data.rbuf.header.h80;
 
        wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
 
@@ -3596,21 +3535,21 @@ static int receive_bitmap(struct drbd_conf *mdev, struct p_header80 *h)
        };
 
        do {
-               if (h->command == P_BITMAP) {
-                       ret = receive_bitmap_plain(mdev, h, buffer, &c);
-               } else if (h->command == P_COMPRESSED_BITMAP) {
+               if (cmd == P_BITMAP) {
+                       ret = receive_bitmap_plain(mdev, data_size, buffer, &c);
+               } else if (cmd == P_COMPRESSED_BITMAP) {
                        /* MAYBE: sanity check that we speak proto >= 90,
                         * and the feature is enabled! */
                        struct p_compressed_bm *p;
 
-                       if (h->length > BM_PACKET_PAYLOAD_BYTES) {
+                       if (data_size > BM_PACKET_PAYLOAD_BYTES) {
                                dev_err(DEV, "ReportCBitmap packet too large\n");
                                goto out;
                        }
                        /* use the page buff */
                        p = buffer;
                        memcpy(p, h, sizeof(*h));
-                       if (drbd_recv(mdev, p->head.payload, h->length) != h->length)
+                       if (drbd_recv(mdev, p->head.payload, data_size) != data_size)
                                goto out;
                        if (p->head.length <= (sizeof(*p) - sizeof(p->head))) {
                                dev_err(DEV, "ReportCBitmap packet too small (l:%u)\n", p->head.length);
@@ -3618,17 +3557,17 @@ static int receive_bitmap(struct drbd_conf *mdev, struct p_header80 *h)
                        }
                        ret = decode_bitmap_c(mdev, p, &c);
                } else {
-                       dev_warn(DEV, "receive_bitmap: h->command neither ReportBitMap nor ReportCBitMap (is 0x%x)", h->command);
+                       dev_warn(DEV, "receive_bitmap: cmd neither ReportBitMap nor ReportCBitMap (is 0x%x)", cmd);
                        goto out;
                }
 
-               c.packets[h->command == P_BITMAP]++;
-               c.bytes[h->command == P_BITMAP] += sizeof(struct p_header80) + h->length;
+               c.packets[cmd == P_BITMAP]++;
+               c.bytes[cmd == P_BITMAP] += sizeof(struct p_header80) + data_size;
 
                if (ret != OK)
                        break;
 
-               if (!drbd_recv_header(mdev, h))
+               if (!drbd_recv_header(mdev, &cmd, &data_size))
                        goto out;
        } while (ret == OK);
        if (ret == FAILED)
@@ -3659,17 +3598,16 @@ static int receive_bitmap(struct drbd_conf *mdev, struct p_header80 *h)
        return ok;
 }
 
-static int receive_skip_(struct drbd_conf *mdev, struct p_header80 *h, int silent)
+static int receive_skip(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
        /* TODO zero copy sink :) */
        static char sink[128];
        int size, want, r;
 
-       if (!silent)
-               dev_warn(DEV, "skipping unknown optional packet type %d, l: %d!\n",
-                    h->command, h->length);
+       dev_warn(DEV, "skipping unknown optional packet type %d, l: %d!\n",
+                cmd, data_size);
 
-       size = h->length;
+       size = data_size;
        while (size > 0) {
                want = min_t(int, size, sizeof(sink));
                r = drbd_recv(mdev, sink, want);
@@ -3679,17 +3617,7 @@ static int receive_skip_(struct drbd_conf *mdev, struct p_header80 *h, int silen
        return size == 0;
 }
 
-static int receive_skip(struct drbd_conf *mdev, struct p_header80 *h)
-{
-       return receive_skip_(mdev, h, 0);
-}
-
-static int receive_skip_silent(struct drbd_conf *mdev, struct p_header80 *h)
-{
-       return receive_skip_(mdev, h, 1);
-}
-
-static int receive_UnplugRemote(struct drbd_conf *mdev, struct p_header80 *h)
+static int receive_UnplugRemote(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
 {
        if (mdev->state.disk >= D_INCONSISTENT)
                drbd_kick_lo(mdev);
@@ -3701,73 +3629,91 @@ static int receive_UnplugRemote(struct drbd_conf *mdev, struct p_header80 *h)
        return TRUE;
 }
 
-typedef int (*drbd_cmd_handler_f)(struct drbd_conf *, struct p_header80 *);
-
-static drbd_cmd_handler_f drbd_default_handler[] = {
-       [P_DATA]            = receive_Data,
-       [P_DATA_REPLY]      = receive_DataReply,
-       [P_RS_DATA_REPLY]   = receive_RSDataReply,
-       [P_BARRIER]         = receive_Barrier,
-       [P_BITMAP]          = receive_bitmap,
-       [P_COMPRESSED_BITMAP]    = receive_bitmap,
-       [P_UNPLUG_REMOTE]   = receive_UnplugRemote,
-       [P_DATA_REQUEST]    = receive_DataRequest,
-       [P_RS_DATA_REQUEST] = receive_DataRequest,
-       [P_SYNC_PARAM]      = receive_SyncParam,
-       [P_SYNC_PARAM89]           = receive_SyncParam,
-       [P_PROTOCOL]        = receive_protocol,
-       [P_UUIDS]           = receive_uuids,
-       [P_SIZES]           = receive_sizes,
-       [P_STATE]           = receive_state,
-       [P_STATE_CHG_REQ]   = receive_req_state,
-       [P_SYNC_UUID]       = receive_sync_uuid,
-       [P_OV_REQUEST]      = receive_DataRequest,
-       [P_OV_REPLY]        = receive_DataRequest,
-       [P_CSUM_RS_REQUEST]    = receive_DataRequest,
-       [P_DELAY_PROBE]     = receive_skip_silent,
+typedef int (*drbd_cmd_handler_f)(struct drbd_conf *, enum drbd_packets cmd, unsigned int to_receive);
+
+struct data_cmd {
+       int expect_payload;
+       size_t pkt_size;
+       drbd_cmd_handler_f function;
+};
+
+static struct data_cmd drbd_cmd_handler[] = {
+       [P_DATA]            = { 1, sizeof(struct p_data), receive_Data },
+       [P_DATA_REPLY]      = { 1, sizeof(struct p_data), receive_DataReply },
+       [P_RS_DATA_REPLY]   = { 1, sizeof(struct p_data), receive_RSDataReply } ,
+       [P_BARRIER]         = { 0, sizeof(struct p_barrier), receive_Barrier } ,
+       [P_BITMAP]          = { 1, sizeof(struct p_header80), receive_bitmap } ,
+       [P_COMPRESSED_BITMAP] = { 1, sizeof(struct p_header80), receive_bitmap } ,
+       [P_UNPLUG_REMOTE]   = { 0, sizeof(struct p_header80), receive_UnplugRemote },
+       [P_DATA_REQUEST]    = { 0, sizeof(struct p_block_req), receive_DataRequest },
+       [P_RS_DATA_REQUEST] = { 0, sizeof(struct p_block_req), receive_DataRequest },
+       [P_SYNC_PARAM]      = { 1, sizeof(struct p_header80), receive_SyncParam },
+       [P_SYNC_PARAM89]    = { 1, sizeof(struct p_header80), receive_SyncParam },
+       [P_PROTOCOL]        = { 1, sizeof(struct p_protocol), receive_protocol },
+       [P_UUIDS]           = { 0, sizeof(struct p_uuids), receive_uuids },
+       [P_SIZES]           = { 0, sizeof(struct p_sizes), receive_sizes },
+       [P_STATE]           = { 0, sizeof(struct p_state), receive_state },
+       [P_STATE_CHG_REQ]   = { 0, sizeof(struct p_req_state), receive_req_state },
+       [P_SYNC_UUID]       = { 0, sizeof(struct p_rs_uuid), receive_sync_uuid },
+       [P_OV_REQUEST]      = { 0, sizeof(struct p_block_req), receive_DataRequest },
+       [P_OV_REPLY]        = { 1, sizeof(struct p_block_req), receive_DataRequest },
+       [P_CSUM_RS_REQUEST] = { 1, sizeof(struct p_block_req), receive_DataRequest },
+       [P_DELAY_PROBE]     = { 0, sizeof(struct p_delay_probe93), receive_skip },
        /* anything missing from this table is in
         * the asender_tbl, see get_asender_cmd */
-       [P_MAX_CMD]         = NULL,
+       [P_MAX_CMD]         = { 0, 0, NULL },
 };
 
-static drbd_cmd_handler_f *drbd_cmd_handler = drbd_default_handler;
-static drbd_cmd_handler_f *drbd_opt_cmd_handler;
+/* All handler functions that expect a sub-header get that sub-heder in
+   mdev->data.rbuf.header.head.payload.
+
+   Usually in mdev->data.rbuf.header.head the callback can find the usual
+   p_header, but they may not rely on that. Since there is also p_header95 !
+ */
 
 static void drbdd(struct drbd_conf *mdev)
 {
-       drbd_cmd_handler_f handler;
-       struct p_header80 *header = &mdev->data.rbuf.header;
+       union p_header *header = &mdev->data.rbuf.header;
+       unsigned int packet_size;
+       enum drbd_packets cmd;
+       size_t shs; /* sub header size */
+       int rv;
 
        while (get_t_state(&mdev->receiver) == Running) {
                drbd_thread_current_set_cpu(mdev);
-               if (!drbd_recv_header(mdev, header)) {
-                       drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
-                       break;
+               if (!drbd_recv_header(mdev, &cmd, &packet_size))
+                       goto err_out;
+
+               if (unlikely(cmd >= P_MAX_CMD || !drbd_cmd_handler[cmd].function)) {
+                       dev_err(DEV, "unknown packet type %d, l: %d!\n", cmd, packet_size);
+                       goto err_out;
                }
 
-               if (header->command < P_MAX_CMD)
-                       handler = drbd_cmd_handler[header->command];
-               else if (P_MAY_IGNORE < header->command
-                    && header->command < P_MAX_OPT_CMD)
-                       handler = drbd_opt_cmd_handler[header->command-P_MAY_IGNORE];
-               else if (header->command > P_MAX_OPT_CMD)
-                       handler = receive_skip;
-               else
-                       handler = NULL;
+               shs = drbd_cmd_handler[cmd].pkt_size - sizeof(union p_header);
+               rv = drbd_recv(mdev, &header->h80.payload, shs);
+               if (unlikely(rv != shs)) {
+                       dev_err(DEV, "short read while reading sub header: rv=%d\n", rv);
+                       goto err_out;
+               }
 
-               if (unlikely(!handler)) {
-                       dev_err(DEV, "unknown packet type %d, l: %d!\n",
-                           header->command, header->length);
-                       drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
-                       break;
+               if (packet_size - shs > 0 && !drbd_cmd_handler[cmd].expect_payload) {
+                       dev_err(DEV, "No payload expected %s l:%d\n", cmdname(cmd), packet_size);
+                       goto err_out;
                }
-               if (unlikely(!handler(mdev, header))) {
+
+               rv = drbd_cmd_handler[cmd].function(mdev, cmd, packet_size - shs);
+
+               if (unlikely(!rv)) {
                        dev_err(DEV, "error receiving %s, l: %d!\n",
-                           cmdname(header->command), header->length);
-                       drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
-                       break;
+                           cmdname(cmd), packet_size);
+                       goto err_out;
                }
        }
+
+       if (0) {
+       err_out:
+               drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
+       }
 }
 
 void drbd_flush_workqueue(struct drbd_conf *mdev)
@@ -3980,27 +3926,28 @@ static int drbd_do_handshake(struct drbd_conf *mdev)
 {
        /* ASSERT current == mdev->receiver ... */
        struct p_handshake *p = &mdev->data.rbuf.handshake;
-       const int expect = sizeof(struct p_handshake)
-                         -sizeof(struct p_header80);
+       const int expect = sizeof(struct p_handshake) - sizeof(struct p_header80);
+       unsigned int length;
+       enum drbd_packets cmd;
        int rv;
 
        rv = drbd_send_handshake(mdev);
        if (!rv)
                return 0;
 
-       rv = drbd_recv_header(mdev, &p->head);
+       rv = drbd_recv_header(mdev, &cmd, &length);
        if (!rv)
                return 0;
 
-       if (p->head.command != P_HAND_SHAKE) {
+       if (cmd != P_HAND_SHAKE) {
                dev_err(DEV, "expected HandShake packet, received: %s (0x%04x)\n",
-                    cmdname(p->head.command), p->head.command);
+                    cmdname(cmd), cmd);
                return -1;
        }
 
-       if (p->head.length != expect) {
+       if (length != expect) {
                dev_err(DEV, "expected HandShake length: %u, received: %u\n",
-                    expect, p->head.length);
+                    expect, length);
                return -1;
        }
 
@@ -4058,10 +4005,11 @@ static int drbd_do_auth(struct drbd_conf *mdev)
        char *response = NULL;
        char *right_response = NULL;
        char *peers_ch = NULL;
-       struct p_header80 p;
        unsigned int key_len = strlen(mdev->net_conf->shared_secret);
        unsigned int resp_size;
        struct hash_desc desc;
+       enum drbd_packets cmd;
+       unsigned int length;
        int rv;
 
        desc.tfm = mdev->cram_hmac_tfm;
@@ -4081,33 +4029,33 @@ static int drbd_do_auth(struct drbd_conf *mdev)
        if (!rv)
                goto fail;
 
-       rv = drbd_recv_header(mdev, &p);
+       rv = drbd_recv_header(mdev, &cmd, &length);
        if (!rv)
                goto fail;
 
-       if (p.command != P_AUTH_CHALLENGE) {
+       if (cmd != P_AUTH_CHALLENGE) {
                dev_err(DEV, "expected AuthChallenge packet, received: %s (0x%04x)\n",
-                   cmdname(p.command), p.command);
+                   cmdname(cmd), cmd);
                rv = 0;
                goto fail;
        }
 
-       if (p.length > CHALLENGE_LEN*2) {
+       if (length > CHALLENGE_LEN * 2) {
                dev_err(DEV, "expected AuthChallenge payload too big.\n");
                rv = -1;
                goto fail;
        }
 
-       peers_ch = kmalloc(p.length, GFP_NOIO);
+       peers_ch = kmalloc(length, GFP_NOIO);
        if (peers_ch == NULL) {
                dev_err(DEV, "kmalloc of peers_ch failed\n");
                rv = -1;
                goto fail;
        }
 
-       rv = drbd_recv(mdev, peers_ch, p.length);
+       rv = drbd_recv(mdev, peers_ch, length);
 
-       if (rv != p.length) {
+       if (rv != length) {
                dev_err(DEV, "short read AuthChallenge: l=%u\n", rv);
                rv = 0;
                goto fail;
@@ -4122,7 +4070,7 @@ static int drbd_do_auth(struct drbd_conf *mdev)
        }
 
        sg_init_table(&sg, 1);
-       sg_set_buf(&sg, peers_ch, p.length);
+       sg_set_buf(&sg, peers_ch, length);
 
        rv = crypto_hash_digest(&desc, &sg, sg.length, response);
        if (rv) {
@@ -4135,18 +4083,18 @@ static int drbd_do_auth(struct drbd_conf *mdev)
        if (!rv)
                goto fail;
 
-       rv = drbd_recv_header(mdev, &p);
+       rv = drbd_recv_header(mdev, &cmd, &length);
        if (!rv)
                goto fail;
 
-       if (p.command != P_AUTH_RESPONSE) {
+       if (cmd != P_AUTH_RESPONSE) {
                dev_err(DEV, "expected AuthResponse packet, received: %s (0x%04x)\n",
-                   cmdname(p.command), p.command);
+                       cmdname(cmd), cmd);
                rv = 0;
                goto fail;
        }
 
-       if (p.length != resp_size) {
+       if (length != resp_size) {
                dev_err(DEV, "expected AuthResponse payload of wrong size\n");
                rv = 0;
                goto fail;
@@ -4474,9 +4422,8 @@ static int got_OVResult(struct drbd_conf *mdev, struct p_header80 *h)
        return TRUE;
 }
 
-static int got_something_to_ignore_m(struct drbd_conf *mdev, struct p_header80 *h)
+static int got_skip(struct drbd_conf *mdev, struct p_header80 *h)
 {
-       /* IGNORE */
        return TRUE;
 }
 
@@ -4504,7 +4451,7 @@ static struct asender_cmd *get_asender_cmd(int cmd)
        [P_BARRIER_ACK]     = { sizeof(struct p_barrier_ack), got_BarrierAck },
        [P_STATE_CHG_REPLY] = { sizeof(struct p_req_state_reply), got_RqSReply },
        [P_RS_IS_IN_SYNC]   = { sizeof(struct p_block_ack), got_IsInSync },
-       [P_DELAY_PROBE]     = { sizeof(struct p_delay_probe93), got_something_to_ignore_m },
+       [P_DELAY_PROBE]     = { sizeof(struct p_delay_probe93), got_skip },
        [P_MAX_CMD]         = { 0, NULL },
        };
        if (cmd > P_MAX_CMD || asender_tbl[cmd].process == NULL)
@@ -4515,7 +4462,7 @@ static struct asender_cmd *get_asender_cmd(int cmd)
 int drbd_asender(struct drbd_thread *thi)
 {
        struct drbd_conf *mdev = thi->mdev;
-       struct p_header80 *h = &mdev->meta.rbuf.header;
+       struct p_header80 *h = &mdev->meta.rbuf.header.h80;
        struct asender_cmd *cmd = NULL;
 
        int rv, len;