The packet pool was previously limited to handling packets contained
within a single buffer.
This patch extends the packet pool to support iovec array,
allowing a single logical packet to be composed of multiple iovec.
To accommodate this, the storage format within the pool is modified.
For a multi-vector packet, a header entry is now stored first with
iov_base = NULL and iov_len holding the number of subsequent
vectors. The actual data vectors are then stored in the following
pool slots.
The packet_add_do() and packet_get_do() functions are updated to
manage this new format for storing and retrieving packets. The
pool_full() check is also adjusted to ensure there is enough
space for all vectors of a new packet before adding it.
Signed-off-by: Laurent Vivier
---
packet.c | 50 +++++++++++++++++++++++++++++++++-----------------
packet.h | 2 +-
tap.c | 4 ++--
3 files changed, 36 insertions(+), 20 deletions(-)
diff --git a/packet.c b/packet.c
index 27693c55a138..919a6b931904 100644
--- a/packet.c
+++ b/packet.c
@@ -93,12 +93,13 @@ static int packet_check_range(const struct pool *p, const char *ptr, size_t len,
/**
* pool_full() - Is a packet pool full?
* @p: Pointer to packet pool
+ * @data: check data can fit in the pool
*
- * Return: true if the pool is full, false if more packets can be added
+ * Return: true if the pool is full, false if data can be added
*/
-bool pool_full(const struct pool *p)
+bool pool_full(const struct pool *p, const struct iov_tail *data)
{
- return p->count >= p->size;
+ return p->count + data->cnt + (data->cnt > 1) >= p->size;
}
/**
@@ -111,11 +112,9 @@ bool pool_full(const struct pool *p)
void packet_add_do(struct pool *p, struct iov_tail *data,
const char *func, int line)
{
- size_t idx = p->count;
- const char *start;
- size_t len;
+ size_t idx = p->count, i, offset;
- if (pool_full(p)) {
+ if (pool_full(p, data)) {
debug("add packet index %zu to pool with size %zu, %s:%i",
idx, p->size, func, line);
return;
@@ -124,18 +123,30 @@ void packet_add_do(struct pool *p, struct iov_tail *data,
if (!iov_tail_prune(data))
return;
- ASSERT(data->cnt == 1); /* we don't support iovec */
+ if (data->cnt > 1) {
+ p->pkt[idx].iov_base = NULL;
+ p->pkt[idx].iov_len = data->cnt;
+ idx++;
+ }
- len = data->iov[0].iov_len - data->off;
- start = (char *)data->iov[0].iov_base + data->off;
+ offset = data->off;
+ for (i = 0; i < data->cnt; i++) {
+ const char *start;
+ size_t len;
- if (packet_check_range(p, start, len, func, line))
- return;
+ len = data->iov[i].iov_len - offset;
+ start = (char *)data->iov[i].iov_base + offset;
+ offset = 0;
- p->pkt[idx].iov_base = (void *)start;
- p->pkt[idx].iov_len = len;
+ if (packet_check_range(p, start, len, func, line))
+ return;
- p->count++;
+ p->pkt[idx].iov_base = (void *)start;
+ p->pkt[idx].iov_len = len;
+ idx++;
+ }
+
+ p->count = idx;
}
/**
@@ -165,9 +176,14 @@ bool packet_get_do(const struct pool *p, size_t idx,
return false;
}
- data->cnt = 1;
+ if (p->pkt[idx].iov_base) {
+ data->cnt = 1;
+ data->iov = &p->pkt[idx];
+ } else {
+ data->cnt = p->pkt[idx].iov_len;
+ data->iov = &p->pkt[idx + 1];
+ }
data->off = 0;
- data->iov = &p->pkt[idx];
for (i = 0; i < data->cnt; i++) {
ASSERT_WITH_MSG(!packet_check_range(p, data->iov[i].iov_base,
diff --git a/packet.h b/packet.h
index e51cbd19fdc4..67dc7deb17db 100644
--- a/packet.h
+++ b/packet.h
@@ -37,7 +37,7 @@ void packet_add_do(struct pool *p, struct iov_tail *data,
const char *func, int line);
bool packet_get_do(const struct pool *p, const size_t idx,
struct iov_tail *data, const char *func, int line);
-bool pool_full(const struct pool *p);
+bool pool_full(const struct pool *p, const struct iov_tail *data);
void pool_flush(struct pool *p);
#define packet_add(p, data) \
diff --git a/tap.c b/tap.c
index 9fd00915bb01..95688b22fcb7 100644
--- a/tap.c
+++ b/tap.c
@@ -1103,14 +1103,14 @@ void tap_add_packet(struct ctx *c, struct iov_tail *data,
switch (ntohs(eh->h_proto)) {
case ETH_P_ARP:
case ETH_P_IP:
- if (pool_full(pool_tap4)) {
+ if (pool_full(pool_tap4, data)) {
tap4_handler(c, pool_tap4, now);
pool_flush(pool_tap4);
}
packet_add(pool_tap4, data);
break;
case ETH_P_IPV6:
- if (pool_full(pool_tap6)) {
+ if (pool_full(pool_tap6, data)) {
tap6_handler(c, pool_tap6, now);
pool_flush(pool_tap6);
}
--
2.49.0