1 // SPDX-License-Identifier: GPL-2.0-or-later
2
3 #include <linux/netdevice.h>
4 #include <net/netdev_queues.h>
5 #include <net/netdev_rx_queue.h>
6
7 #include "page_pool_priv.h"
8
netdev_rx_queue_restart(struct net_device * dev,unsigned int rxq_idx)9 int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx)
10 {
11 struct netdev_rx_queue *rxq = __netif_get_rx_queue(dev, rxq_idx);
12 void *new_mem, *old_mem;
13 int err;
14
15 if (!dev->queue_mgmt_ops || !dev->queue_mgmt_ops->ndo_queue_stop ||
16 !dev->queue_mgmt_ops->ndo_queue_mem_free ||
17 !dev->queue_mgmt_ops->ndo_queue_mem_alloc ||
18 !dev->queue_mgmt_ops->ndo_queue_start)
19 return -EOPNOTSUPP;
20
21 ASSERT_RTNL();
22
23 new_mem = kvzalloc(dev->queue_mgmt_ops->ndo_queue_mem_size, GFP_KERNEL);
24 if (!new_mem)
25 return -ENOMEM;
26
27 old_mem = kvzalloc(dev->queue_mgmt_ops->ndo_queue_mem_size, GFP_KERNEL);
28 if (!old_mem) {
29 err = -ENOMEM;
30 goto err_free_new_mem;
31 }
32
33 err = dev->queue_mgmt_ops->ndo_queue_mem_alloc(dev, new_mem, rxq_idx);
34 if (err)
35 goto err_free_old_mem;
36
37 err = page_pool_check_memory_provider(dev, rxq);
38 if (err)
39 goto err_free_new_queue_mem;
40
41 err = dev->queue_mgmt_ops->ndo_queue_stop(dev, old_mem, rxq_idx);
42 if (err)
43 goto err_free_new_queue_mem;
44
45 err = dev->queue_mgmt_ops->ndo_queue_start(dev, new_mem, rxq_idx);
46 if (err)
47 goto err_start_queue;
48
49 dev->queue_mgmt_ops->ndo_queue_mem_free(dev, old_mem);
50
51 kvfree(old_mem);
52 kvfree(new_mem);
53
54 return 0;
55
56 err_start_queue:
57 /* Restarting the queue with old_mem should be successful as we haven't
58 * changed any of the queue configuration, and there is not much we can
59 * do to recover from a failure here.
60 *
61 * WARN if we fail to recover the old rx queue, and at least free
62 * old_mem so we don't also leak that.
63 */
64 if (dev->queue_mgmt_ops->ndo_queue_start(dev, old_mem, rxq_idx)) {
65 WARN(1,
66 "Failed to restart old queue in error path. RX queue %d may be unhealthy.",
67 rxq_idx);
68 dev->queue_mgmt_ops->ndo_queue_mem_free(dev, old_mem);
69 }
70
71 err_free_new_queue_mem:
72 dev->queue_mgmt_ops->ndo_queue_mem_free(dev, new_mem);
73
74 err_free_old_mem:
75 kvfree(old_mem);
76
77 err_free_new_mem:
78 kvfree(new_mem);
79
80 return err;
81 }
82