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virtio_net: Support dynamic rss indirection table size

When reading/writing virtio_net_ctrl_rss, we get the indirection table
size from vi->rss_indir_table_size, which is initialized in
virtnet_probe(). However, the actual size of indirection_table was set
as VIRTIO_NET_RSS_MAX_TABLE_LEN=128. This collision may cause issues if
the vi->rss_indir_table_size exceeds 128.

This patch instead uses dynamic indirection table, allocated with
vi->rss after vi->rss_indir_table_size initialized. And free it in
virtnet_remove().

In virtnet_commit_rss_command(), sgs for rss is initialized differently
with hash_report. So indirection_table is not used if !vi->has_rss, and
then we don't need to alloc indirection_table for hash_report only uses.

Fixes: c7114b1249 ("drivers/net/virtio_net: Added basic RSS support.")
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Joe Damato <jdamato@fastly.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Philo Lu 2024-11-04 16:57:03 +08:00 committed by Paolo Abeni
parent 25d7070214
commit 86a48a00ef

View File

@ -368,15 +368,16 @@ struct receive_queue {
* because table sizes may be differ according to the device configuration.
*/
#define VIRTIO_NET_RSS_MAX_KEY_SIZE 40
#define VIRTIO_NET_RSS_MAX_TABLE_LEN 128
struct virtio_net_ctrl_rss {
u32 hash_types;
u16 indirection_table_mask;
u16 unclassified_queue;
u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN];
u16 hash_cfg_reserved; /* for HASH_CONFIG (see virtio_net_hash_config for details) */
u16 max_tx_vq;
u8 hash_key_length;
u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE];
u16 *indirection_table;
};
/* Control VQ buffers: protected by the rtnl lock */
@ -512,6 +513,25 @@ static struct sk_buff *virtnet_skb_append_frag(struct sk_buff *head_skb,
struct page *page, void *buf,
int len, int truesize);
static int rss_indirection_table_alloc(struct virtio_net_ctrl_rss *rss, u16 indir_table_size)
{
if (!indir_table_size) {
rss->indirection_table = NULL;
return 0;
}
rss->indirection_table = kmalloc_array(indir_table_size, sizeof(u16), GFP_KERNEL);
if (!rss->indirection_table)
return -ENOMEM;
return 0;
}
static void rss_indirection_table_free(struct virtio_net_ctrl_rss *rss)
{
kfree(rss->indirection_table);
}
static bool is_xdp_frame(void *ptr)
{
return (unsigned long)ptr & VIRTIO_XDP_FLAG;
@ -3828,11 +3848,15 @@ static bool virtnet_commit_rss_command(struct virtnet_info *vi)
/* prepare sgs */
sg_init_table(sgs, 4);
sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table);
sg_buf_size = offsetof(struct virtio_net_ctrl_rss, hash_cfg_reserved);
sg_set_buf(&sgs[0], &vi->rss, sg_buf_size);
sg_buf_size = sizeof(uint16_t) * (vi->rss.indirection_table_mask + 1);
sg_set_buf(&sgs[1], vi->rss.indirection_table, sg_buf_size);
if (vi->has_rss) {
sg_buf_size = sizeof(uint16_t) * vi->rss_indir_table_size;
sg_set_buf(&sgs[1], vi->rss.indirection_table, sg_buf_size);
} else {
sg_set_buf(&sgs[1], &vi->rss.hash_cfg_reserved, sizeof(uint16_t));
}
sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key)
- offsetof(struct virtio_net_ctrl_rss, max_tx_vq);
@ -6420,6 +6444,9 @@ static int virtnet_probe(struct virtio_device *vdev)
virtio_cread16(vdev, offsetof(struct virtio_net_config,
rss_max_indirection_table_length));
}
err = rss_indirection_table_alloc(&vi->rss, vi->rss_indir_table_size);
if (err)
goto free;
if (vi->has_rss || vi->has_rss_hash_report) {
vi->rss_key_size =
@ -6674,6 +6701,8 @@ static void virtnet_remove(struct virtio_device *vdev)
remove_vq_common(vi);
rss_indirection_table_free(&vi->rss);
free_netdev(vi->dev);
}