This is the key memory-model change for MQ RX.
Legacy ibmveth uses five adapter-level RX buffer pools (512 B
through 64 KiB slots). pool_active[] enables the standard-MTU pools by
default; larger pools activate when MTU requires them. With single-queue
RX that set is shared on one completion path.
MQ requires the same pool model per queue: buffers post with
H_ADD_LOGICAL_LAN_BUFFERS_QUEUE against a queue handle and completions
return on that queue. Sharing pools across queues would mix ownership and
break queue-local replenish/drain/teardown.
Refactor around queue-local pools with static geometry (still defined at
probe on queue 0, copied to queues 1..N at alloc time):
rx_buff_pool[queue][pool]
ibmveth_alloc_queue_buffer_pools()
ibmveth_free_queue_buffer_pools()
ibmveth_alloc_buffer_pools() / ibmveth_free_buffer_pools()
Queue 0 remains the template for pool geometry (size, buff_size,
threshold, active). For queues 1..N we copy metadata from queue 0, then
allocate actual backing arrays/skbs per queue.
At the default 1500-byte MTU, pool 4 (64 KiB buffers) is not needed and
costs guest memory when allocated per queue in MQ mode. Clear
pool_active[4] so open() skips it; ibmveth_change_mtu() still enables
larger pools when MTU warrants jumbo frames.
Error handling is also made queue-safe:
- if allocation fails in one pool, unwind only what was allocated for
that queue, then unwind prior queues in the caller
- free paths release pools based on real allocations
(free_map/dma_addr/skbuff), not only pool->active
That allocation-based free check is intentional: later resize and failure
paths can leave memory allocated even when active was already cleared.
Freeing by allocation state avoids leaks and double-free corner cases.
This split keeps the per-queue pool design isolated and reviewable ahead
of the MQ datapath enable commit later in the series.
Signed-off-by: Mingming Cao <[email protected]>
Reviewed-by: Dave Marquardt <[email protected]>
---
drivers/net/ethernet/ibm/ibmveth.c | 127 +++++++++++++++++++++++++++++
drivers/net/ethernet/ibm/ibmveth.h | 2 +-
2 files changed, 128 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/ibm/ibmveth.c
b/drivers/net/ethernet/ibm/ibmveth.c
index b8adc9935471..95068fb20dba 100644
--- a/drivers/net/ethernet/ibm/ibmveth.c
+++ b/drivers/net/ethernet/ibm/ibmveth.c
@@ -611,6 +611,133 @@ static void ibmveth_free_buffer_pool(struct
ibmveth_adapter *adapter,
}
}
+/**
+ * ibmveth_alloc_queue_buffer_pools - Allocate buffer pools for a single queue
+ * @adapter: ibmveth adapter structure
+ * @queue: queue index
+ *
+ * Allocates all active buffer pools for the specified queue.
+ * Pool metadata must be initialized before calling this function.
+ *
+ * Return: 0 on success, negative error code on failure
+ */
+static int ibmveth_alloc_queue_buffer_pools(struct ibmveth_adapter *adapter,
+ int queue)
+{
+ struct net_device *netdev = adapter->netdev;
+ int i;
+
+ for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
+ if (!adapter->rx_buff_pool[queue][i].active)
+ continue;
+
+ if
(ibmveth_alloc_buffer_pool(&adapter->rx_buff_pool[queue][i])) {
+ netdev_err(netdev,
+ "unable to allocate buffer pool %d for queue
%d (size=%u, count=%u)\n",
+ i, queue,
+ adapter->rx_buff_pool[queue][i].buff_size,
+ adapter->rx_buff_pool[queue][i].size);
+ adapter->rx_buff_pool[queue][i].active = 0;
+
+ /* Free pools allocated so far for this queue */
+ while (--i >= 0) {
+ if (adapter->rx_buff_pool[queue][i].active)
+ ibmveth_free_buffer_pool(adapter,
+
&adapter->rx_buff_pool[queue][i]);
+ }
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * ibmveth_free_queue_buffer_pools - Free buffer pools for a single queue
+ * @adapter: ibmveth adapter structure
+ * @queue: queue index
+ *
+ * Frees all active buffer pools for the specified queue.
+ */
+static void ibmveth_free_queue_buffer_pools(struct ibmveth_adapter *adapter,
+ int queue)
+{
+ int i;
+
+ for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
+ struct ibmveth_buff_pool *pool =
&adapter->rx_buff_pool[queue][i];
+
+ /* Free pool if it has allocated memory, regardless of active
flag.
+ * Pools may have memory allocated but not marked active during
+ * queue scale-up, so we must check for actual allocations.
+ */
+ if (pool->free_map || pool->dma_addr || pool->skbuff)
+ ibmveth_free_buffer_pool(adapter, pool);
+ }
+}
+
+/**
+ * ibmveth_alloc_buffer_pools - Allocate buffer pools for all queues
+ * @adapter: ibmveth adapter structure
+ *
+ * Initializes pool metadata for queues 1-N from queue 0 settings,
+ * then allocates buffer pools for all queues using the helper function.
+ *
+ * Return: 0 on success, negative error code on failure
+ */
+static int __maybe_unused ibmveth_alloc_buffer_pools(struct ibmveth_adapter
*adapter)
+{
+ struct net_device *netdev = adapter->netdev;
+ int i, q, rc;
+
+ /* Initialize pool metadata for queues 1-15 from queue 0 settings */
+ for (q = 1; q < adapter->num_rx_queues; q++) {
+ for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
+ struct ibmveth_buff_pool *src =
&adapter->rx_buff_pool[0][i];
+ struct ibmveth_buff_pool *dst =
&adapter->rx_buff_pool[q][i];
+
+ dst->size = src->size;
+ dst->index = src->index;
+ dst->buff_size = src->buff_size;
+ dst->threshold = src->threshold;
+ dst->active = src->active;
+ }
+ }
+
+ /* Allocate actual buffers for all queues */
+ for (q = 0; q < adapter->num_rx_queues; q++) {
+ rc = ibmveth_alloc_queue_buffer_pools(adapter, q);
+ if (rc) {
+ /* Free pools for all previous queues */
+ while (--q >= 0)
+ ibmveth_free_queue_buffer_pools(adapter, q);
+ return rc;
+ }
+ }
+
+ netdev_dbg(netdev, "allocated buffer pools for %d queue(s)\n",
+ adapter->num_rx_queues);
+ return 0;
+}
+
+/**
+ * ibmveth_free_buffer_pools - Free buffer pools for all queues
+ * @adapter: ibmveth adapter structure
+ *
+ * Frees buffer pools for all queues using the helper function.
+ */
+static void __maybe_unused ibmveth_free_buffer_pools(struct ibmveth_adapter
*adapter)
+{
+ int q;
+
+ /* Free buffer pools for all queues */
+ for (q = 0; q < adapter->num_rx_queues; q++)
+ ibmveth_free_queue_buffer_pools(adapter, q);
+
+ netdev_dbg(adapter->netdev, "freed buffer pools for %d queue(s)\n",
+ adapter->num_rx_queues);
+}
+
/**
* ibmveth_remove_buffer_from_pool - remove a buffer from a pool
* @adapter: adapter instance
diff --git a/drivers/net/ethernet/ibm/ibmveth.h
b/drivers/net/ethernet/ibm/ibmveth.h
index f0dffe42e8fe..d2ceeccd5fbd 100644
--- a/drivers/net/ethernet/ibm/ibmveth.h
+++ b/drivers/net/ethernet/ibm/ibmveth.h
@@ -286,7 +286,7 @@ static inline long h_illan_attributes(unsigned long
unit_address,
static int pool_size[] = { 512, 1024 * 2, 1024 * 16, 1024 * 32, 1024 * 64 };
static int pool_count[] = { 256, 512, 256, 256, 256 };
static int pool_count_cmo[] = { 256, 512, 256, 256, 64 };
-static int pool_active[] = { 1, 1, 0, 0, 1};
+static int pool_active[] = { 1, 1, 0, 0, 0};
#define IBM_VETH_INVALID_MAP ((u16)0xffff)
--
2.39.3 (Apple Git-146)
