core,bindings: Allow bindings to specify packet size
Currently, we fix all packet sizes to the baseline MTU size. However,
bindings may support larger packet sizes.
This change makes the packet allocator use binding-specific parameters
to suit the binding itself, and uses the max packet size in the
packetisation path.
Since packet sizes may now exceed 255, we change the size and offset
types from uint8_t to size_t.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Change-Id: Ica932479f251dc33c67ea19e9e3e5a193cbe0b32
diff --git a/core.c b/core.c
index 2a9784e..ff4bd63 100644
--- a/core.c
+++ b/core.c
@@ -60,16 +60,18 @@
#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
#endif
-struct mctp_pktbuf *mctp_pktbuf_alloc(uint8_t len)
+struct mctp_pktbuf *mctp_pktbuf_alloc(struct mctp_binding *binding, size_t len)
{
struct mctp_pktbuf *buf;
+ size_t size;
- BUILD_ASSERT(MCTP_PKTBUF_SIZE <= 0xff);
+ size = binding->pkt_size + binding->pkt_pad;
/* todo: pools */
- buf = __mctp_alloc(sizeof(*buf));
+ buf = __mctp_alloc(sizeof(*buf) + size);
- buf->start = MCTP_PKTBUF_BINDING_PAD;
+ buf->size = size;
+ buf->start = binding->pkt_pad;
buf->end = buf->start + len;
buf->mctp_hdr_off = buf->start;
buf->next = NULL;
@@ -97,30 +99,28 @@
return pkt->end - pkt->start;
}
-void *mctp_pktbuf_alloc_start(struct mctp_pktbuf *pkt, uint8_t size)
+void *mctp_pktbuf_alloc_start(struct mctp_pktbuf *pkt, size_t size)
{
assert(size <= pkt->start);
pkt->start -= size;
return pkt->data + pkt->start;
}
-void *mctp_pktbuf_alloc_end(struct mctp_pktbuf *pkt, uint8_t size)
+void *mctp_pktbuf_alloc_end(struct mctp_pktbuf *pkt, size_t size)
{
void *buf;
- assert(size < (MCTP_PKTBUF_SIZE - pkt->end));
+ assert(size < (pkt->size - pkt->end));
buf = pkt->data + pkt->end;
pkt->end += size;
return buf;
}
-int mctp_pktbuf_push(struct mctp_pktbuf *pkt, void *data, uint8_t len)
+int mctp_pktbuf_push(struct mctp_pktbuf *pkt, void *data, size_t len)
{
void *p;
- assert(pkt->end + len <= MCTP_PKTBUF_SIZE);
-
- if (pkt->end + len > MCTP_PKTBUF_SIZE)
+ if (pkt->end + len > pkt->size)
return -1;
p = pkt->data + pkt->end;
@@ -355,9 +355,6 @@
if (!bus->tx_enabled)
return -1;
- mctp_prdebug("sending pkt, len %d",
- mctp_pktbuf_size(pkt));
-
return bus->binding->tx(bus->binding, pkt);
}
@@ -392,21 +389,22 @@
int mctp_message_tx(struct mctp *mctp, mctp_eid_t eid,
void *msg, size_t msg_len)
{
+ size_t max_payload_len, payload_len, p;
struct mctp_pktbuf *pkt;
struct mctp_hdr *hdr;
struct mctp_bus *bus;
- size_t pkt_len, p;
int i;
bus = find_bus_for_eid(mctp, eid);
+ max_payload_len = bus->binding->pkt_size - sizeof(*hdr);
/* queue up packets, each of max MCTP_MTU size */
for (p = 0, i = 0; p < msg_len; i++) {
- pkt_len = msg_len - p;
- if (pkt_len > MCTP_MTU)
- pkt_len = MCTP_MTU;
+ payload_len = msg_len - p;
+ if (payload_len > max_payload_len)
+ payload_len = max_payload_len;
- pkt = mctp_pktbuf_alloc(pkt_len + sizeof(*hdr));
+ pkt = mctp_pktbuf_alloc(bus->binding, payload_len + sizeof(*hdr));
hdr = mctp_pktbuf_hdr(pkt);
/* todo: tags */
@@ -418,12 +416,12 @@
if (i == 0)
hdr->flags_seq_tag |= MCTP_HDR_FLAG_SOM;
- if (p + pkt_len >= msg_len)
+ if (p + payload_len >= msg_len)
hdr->flags_seq_tag |= MCTP_HDR_FLAG_EOM;
hdr->flags_seq_tag |=
(i & MCTP_HDR_SEQ_MASK) << MCTP_HDR_SEQ_SHIFT;
- memcpy(mctp_pktbuf_data(pkt), msg + p, pkt_len);
+ memcpy(mctp_pktbuf_data(pkt), msg + p, payload_len);
/* add to tx queue */
if (bus->tx_queue_tail)
@@ -432,7 +430,7 @@
bus->tx_queue_head = pkt;
bus->tx_queue_tail = pkt;
- p += pkt_len;
+ p += payload_len;
}
mctp_send_tx_queue(bus);