/*
|
* Copyright (C) ST-Ericsson AB 2013
|
* Authors: Vicram Arv
|
* Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
|
* Sjur Brendeland
|
* License terms: GNU General Public License (GPL) version 2
|
*/
|
#include <linux/module.h>
|
#include <linux/if_arp.h>
|
#include <linux/virtio.h>
|
#include <linux/vringh.h>
|
#include <linux/debugfs.h>
|
#include <linux/spinlock.h>
|
#include <linux/genalloc.h>
|
#include <linux/interrupt.h>
|
#include <linux/netdevice.h>
|
#include <linux/rtnetlink.h>
|
#include <linux/virtio_ids.h>
|
#include <linux/virtio_caif.h>
|
#include <linux/virtio_ring.h>
|
#include <linux/dma-mapping.h>
|
#include <net/caif/caif_dev.h>
|
#include <linux/virtio_config.h>
|
|
MODULE_LICENSE("GPL v2");
|
MODULE_AUTHOR("Vicram Arv");
|
MODULE_AUTHOR("Sjur Brendeland");
|
MODULE_DESCRIPTION("Virtio CAIF Driver");
|
|
/* NAPI schedule quota */
|
#define CFV_DEFAULT_QUOTA 32
|
|
/* Defaults used if virtio config space is unavailable */
|
#define CFV_DEF_MTU_SIZE 4096
|
#define CFV_DEF_HEADROOM 32
|
#define CFV_DEF_TAILROOM 32
|
|
/* Required IP header alignment */
|
#define IP_HDR_ALIGN 4
|
|
/* struct cfv_napi_contxt - NAPI context info
|
* @riov: IOV holding data read from the ring. Note that riov may
|
* still hold data when cfv_rx_poll() returns.
|
* @head: Last descriptor ID we received from vringh_getdesc_kern.
|
* We use this to put descriptor back on the used ring. USHRT_MAX is
|
* used to indicate invalid head-id.
|
*/
|
struct cfv_napi_context {
|
struct vringh_kiov riov;
|
unsigned short head;
|
};
|
|
/* struct cfv_stats - statistics for debugfs
|
* @rx_napi_complete: Number of NAPI completions (RX)
|
* @rx_napi_resched: Number of calls where the full quota was used (RX)
|
* @rx_nomem: Number of SKB alloc failures (RX)
|
* @rx_kicks: Number of RX kicks
|
* @tx_full_ring: Number times TX ring was full
|
* @tx_no_mem: Number of times TX went out of memory
|
* @tx_flow_on: Number of flow on (TX)
|
* @tx_kicks: Number of TX kicks
|
*/
|
struct cfv_stats {
|
u32 rx_napi_complete;
|
u32 rx_napi_resched;
|
u32 rx_nomem;
|
u32 rx_kicks;
|
u32 tx_full_ring;
|
u32 tx_no_mem;
|
u32 tx_flow_on;
|
u32 tx_kicks;
|
};
|
|
/* struct cfv_info - Caif Virtio control structure
|
* @cfdev: caif common header
|
* @vdev: Associated virtio device
|
* @vr_rx: rx/downlink host vring
|
* @vq_tx: tx/uplink virtqueue
|
* @ndev: CAIF link layer device
|
* @watermark_tx: indicates number of free descriptors we need
|
* to reopen the tx-queues after overload.
|
* @tx_lock: protects vq_tx from concurrent use
|
* @tx_release_tasklet: Tasklet for freeing consumed TX buffers
|
* @napi: Napi context used in cfv_rx_poll()
|
* @ctx: Context data used in cfv_rx_poll()
|
* @tx_hr: transmit headroom
|
* @rx_hr: receive headroom
|
* @tx_tr: transmit tail room
|
* @rx_tr: receive tail room
|
* @mtu: transmit max size
|
* @mru: receive max size
|
* @allocsz: size of dma memory reserved for TX buffers
|
* @alloc_addr: virtual address to dma memory for TX buffers
|
* @alloc_dma: dma address to dma memory for TX buffers
|
* @genpool: Gen Pool used for allocating TX buffers
|
* @reserved_mem: Pointer to memory reserve allocated from genpool
|
* @reserved_size: Size of memory reserve allocated from genpool
|
* @stats: Statistics exposed in sysfs
|
* @debugfs: Debugfs dentry for statistic counters
|
*/
|
struct cfv_info {
|
struct caif_dev_common cfdev;
|
struct virtio_device *vdev;
|
struct vringh *vr_rx;
|
struct virtqueue *vq_tx;
|
struct net_device *ndev;
|
unsigned int watermark_tx;
|
/* Protect access to vq_tx */
|
spinlock_t tx_lock;
|
struct tasklet_struct tx_release_tasklet;
|
struct napi_struct napi;
|
struct cfv_napi_context ctx;
|
u16 tx_hr;
|
u16 rx_hr;
|
u16 tx_tr;
|
u16 rx_tr;
|
u32 mtu;
|
u32 mru;
|
size_t allocsz;
|
void *alloc_addr;
|
dma_addr_t alloc_dma;
|
struct gen_pool *genpool;
|
unsigned long reserved_mem;
|
size_t reserved_size;
|
struct cfv_stats stats;
|
struct dentry *debugfs;
|
};
|
|
/* struct buf_info - maintains transmit buffer data handle
|
* @size: size of transmit buffer
|
* @dma_handle: handle to allocated dma device memory area
|
* @vaddr: virtual address mapping to allocated memory area
|
*/
|
struct buf_info {
|
size_t size;
|
u8 *vaddr;
|
};
|
|
/* Called from virtio device, in IRQ context */
|
static void cfv_release_cb(struct virtqueue *vq_tx)
|
{
|
struct cfv_info *cfv = vq_tx->vdev->priv;
|
|
++cfv->stats.tx_kicks;
|
tasklet_schedule(&cfv->tx_release_tasklet);
|
}
|
|
static void free_buf_info(struct cfv_info *cfv, struct buf_info *buf_info)
|
{
|
if (!buf_info)
|
return;
|
gen_pool_free(cfv->genpool, (unsigned long) buf_info->vaddr,
|
buf_info->size);
|
kfree(buf_info);
|
}
|
|
/* This is invoked whenever the remote processor completed processing
|
* a TX msg we just sent, and the buffer is put back to the used ring.
|
*/
|
static void cfv_release_used_buf(struct virtqueue *vq_tx)
|
{
|
struct cfv_info *cfv = vq_tx->vdev->priv;
|
unsigned long flags;
|
|
BUG_ON(vq_tx != cfv->vq_tx);
|
|
for (;;) {
|
unsigned int len;
|
struct buf_info *buf_info;
|
|
/* Get used buffer from used ring to recycle used descriptors */
|
spin_lock_irqsave(&cfv->tx_lock, flags);
|
buf_info = virtqueue_get_buf(vq_tx, &len);
|
spin_unlock_irqrestore(&cfv->tx_lock, flags);
|
|
/* Stop looping if there are no more buffers to free */
|
if (!buf_info)
|
break;
|
|
free_buf_info(cfv, buf_info);
|
|
/* watermark_tx indicates if we previously stopped the tx
|
* queues. If we have enough free stots in the virtio ring,
|
* re-establish memory reserved and open up tx queues.
|
*/
|
if (cfv->vq_tx->num_free <= cfv->watermark_tx)
|
continue;
|
|
/* Re-establish memory reserve */
|
if (cfv->reserved_mem == 0 && cfv->genpool)
|
cfv->reserved_mem =
|
gen_pool_alloc(cfv->genpool,
|
cfv->reserved_size);
|
|
/* Open up the tx queues */
|
if (cfv->reserved_mem) {
|
cfv->watermark_tx =
|
virtqueue_get_vring_size(cfv->vq_tx);
|
netif_tx_wake_all_queues(cfv->ndev);
|
/* Buffers are recycled in cfv_netdev_tx, so
|
* disable notifications when queues are opened.
|
*/
|
virtqueue_disable_cb(cfv->vq_tx);
|
++cfv->stats.tx_flow_on;
|
} else {
|
/* if no memory reserve, wait for more free slots */
|
WARN_ON(cfv->watermark_tx >
|
virtqueue_get_vring_size(cfv->vq_tx));
|
cfv->watermark_tx +=
|
virtqueue_get_vring_size(cfv->vq_tx) / 4;
|
}
|
}
|
}
|
|
/* Allocate a SKB and copy packet data to it */
|
static struct sk_buff *cfv_alloc_and_copy_skb(int *err,
|
struct cfv_info *cfv,
|
u8 *frm, u32 frm_len)
|
{
|
struct sk_buff *skb;
|
u32 cfpkt_len, pad_len;
|
|
*err = 0;
|
/* Verify that packet size with down-link header and mtu size */
|
if (frm_len > cfv->mru || frm_len <= cfv->rx_hr + cfv->rx_tr) {
|
netdev_err(cfv->ndev,
|
"Invalid frmlen:%u mtu:%u hr:%d tr:%d\n",
|
frm_len, cfv->mru, cfv->rx_hr,
|
cfv->rx_tr);
|
*err = -EPROTO;
|
return NULL;
|
}
|
|
cfpkt_len = frm_len - (cfv->rx_hr + cfv->rx_tr);
|
pad_len = (unsigned long)(frm + cfv->rx_hr) & (IP_HDR_ALIGN - 1);
|
|
skb = netdev_alloc_skb(cfv->ndev, frm_len + pad_len);
|
if (!skb) {
|
*err = -ENOMEM;
|
return NULL;
|
}
|
|
skb_reserve(skb, cfv->rx_hr + pad_len);
|
|
skb_put_data(skb, frm + cfv->rx_hr, cfpkt_len);
|
return skb;
|
}
|
|
/* Get packets from the host vring */
|
static int cfv_rx_poll(struct napi_struct *napi, int quota)
|
{
|
struct cfv_info *cfv = container_of(napi, struct cfv_info, napi);
|
int rxcnt = 0;
|
int err = 0;
|
void *buf;
|
struct sk_buff *skb;
|
struct vringh_kiov *riov = &cfv->ctx.riov;
|
unsigned int skb_len;
|
|
do {
|
skb = NULL;
|
|
/* Put the previous iovec back on the used ring and
|
* fetch a new iovec if we have processed all elements.
|
*/
|
if (riov->i == riov->used) {
|
if (cfv->ctx.head != USHRT_MAX) {
|
vringh_complete_kern(cfv->vr_rx,
|
cfv->ctx.head,
|
0);
|
cfv->ctx.head = USHRT_MAX;
|
}
|
|
err = vringh_getdesc_kern(
|
cfv->vr_rx,
|
riov,
|
NULL,
|
&cfv->ctx.head,
|
GFP_ATOMIC);
|
|
if (err <= 0)
|
goto exit;
|
}
|
|
buf = phys_to_virt((unsigned long) riov->iov[riov->i].iov_base);
|
/* TODO: Add check on valid buffer address */
|
|
skb = cfv_alloc_and_copy_skb(&err, cfv, buf,
|
riov->iov[riov->i].iov_len);
|
if (unlikely(err))
|
goto exit;
|
|
/* Push received packet up the stack. */
|
skb_len = skb->len;
|
skb->protocol = htons(ETH_P_CAIF);
|
skb_reset_mac_header(skb);
|
skb->dev = cfv->ndev;
|
err = netif_receive_skb(skb);
|
if (unlikely(err)) {
|
++cfv->ndev->stats.rx_dropped;
|
} else {
|
++cfv->ndev->stats.rx_packets;
|
cfv->ndev->stats.rx_bytes += skb_len;
|
}
|
|
++riov->i;
|
++rxcnt;
|
} while (rxcnt < quota);
|
|
++cfv->stats.rx_napi_resched;
|
goto out;
|
|
exit:
|
switch (err) {
|
case 0:
|
++cfv->stats.rx_napi_complete;
|
|
/* Really out of patckets? (stolen from virtio_net)*/
|
napi_complete(napi);
|
if (unlikely(!vringh_notify_enable_kern(cfv->vr_rx)) &&
|
napi_schedule_prep(napi)) {
|
vringh_notify_disable_kern(cfv->vr_rx);
|
__napi_schedule(napi);
|
}
|
break;
|
|
case -ENOMEM:
|
++cfv->stats.rx_nomem;
|
dev_kfree_skb(skb);
|
/* Stop NAPI poll on OOM, we hope to be polled later */
|
napi_complete(napi);
|
vringh_notify_enable_kern(cfv->vr_rx);
|
break;
|
|
default:
|
/* We're doomed, any modem fault is fatal */
|
netdev_warn(cfv->ndev, "Bad ring, disable device\n");
|
cfv->ndev->stats.rx_dropped = riov->used - riov->i;
|
napi_complete(napi);
|
vringh_notify_disable_kern(cfv->vr_rx);
|
netif_carrier_off(cfv->ndev);
|
break;
|
}
|
out:
|
if (rxcnt && vringh_need_notify_kern(cfv->vr_rx) > 0)
|
vringh_notify(cfv->vr_rx);
|
return rxcnt;
|
}
|
|
static void cfv_recv(struct virtio_device *vdev, struct vringh *vr_rx)
|
{
|
struct cfv_info *cfv = vdev->priv;
|
|
++cfv->stats.rx_kicks;
|
vringh_notify_disable_kern(cfv->vr_rx);
|
napi_schedule(&cfv->napi);
|
}
|
|
static void cfv_destroy_genpool(struct cfv_info *cfv)
|
{
|
if (cfv->alloc_addr)
|
dma_free_coherent(cfv->vdev->dev.parent->parent,
|
cfv->allocsz, cfv->alloc_addr,
|
cfv->alloc_dma);
|
|
if (!cfv->genpool)
|
return;
|
gen_pool_free(cfv->genpool, cfv->reserved_mem,
|
cfv->reserved_size);
|
gen_pool_destroy(cfv->genpool);
|
cfv->genpool = NULL;
|
}
|
|
static int cfv_create_genpool(struct cfv_info *cfv)
|
{
|
int err;
|
|
/* dma_alloc can only allocate whole pages, and we need a more
|
* fine graned allocation so we use genpool. We ask for space needed
|
* by IP and a full ring. If the dma allcoation fails we retry with a
|
* smaller allocation size.
|
*/
|
err = -ENOMEM;
|
cfv->allocsz = (virtqueue_get_vring_size(cfv->vq_tx) *
|
(ETH_DATA_LEN + cfv->tx_hr + cfv->tx_tr) * 11)/10;
|
if (cfv->allocsz <= (num_possible_cpus() + 1) * cfv->ndev->mtu)
|
return -EINVAL;
|
|
for (;;) {
|
if (cfv->allocsz <= num_possible_cpus() * cfv->ndev->mtu) {
|
netdev_info(cfv->ndev, "Not enough device memory\n");
|
return -ENOMEM;
|
}
|
|
cfv->alloc_addr = dma_alloc_coherent(
|
cfv->vdev->dev.parent->parent,
|
cfv->allocsz, &cfv->alloc_dma,
|
GFP_ATOMIC);
|
if (cfv->alloc_addr)
|
break;
|
|
cfv->allocsz = (cfv->allocsz * 3) >> 2;
|
}
|
|
netdev_dbg(cfv->ndev, "Allocated %zd bytes from dma-memory\n",
|
cfv->allocsz);
|
|
/* Allocate on 128 bytes boundaries (1 << 7)*/
|
cfv->genpool = gen_pool_create(7, -1);
|
if (!cfv->genpool)
|
goto err;
|
|
err = gen_pool_add_virt(cfv->genpool, (unsigned long)cfv->alloc_addr,
|
(phys_addr_t)virt_to_phys(cfv->alloc_addr),
|
cfv->allocsz, -1);
|
if (err)
|
goto err;
|
|
/* Reserve some memory for low memory situations. If we hit the roof
|
* in the memory pool, we stop TX flow and release the reserve.
|
*/
|
cfv->reserved_size = num_possible_cpus() * cfv->ndev->mtu;
|
cfv->reserved_mem = gen_pool_alloc(cfv->genpool,
|
cfv->reserved_size);
|
if (!cfv->reserved_mem) {
|
err = -ENOMEM;
|
goto err;
|
}
|
|
cfv->watermark_tx = virtqueue_get_vring_size(cfv->vq_tx);
|
return 0;
|
err:
|
cfv_destroy_genpool(cfv);
|
return err;
|
}
|
|
/* Enable the CAIF interface and allocate the memory-pool */
|
static int cfv_netdev_open(struct net_device *netdev)
|
{
|
struct cfv_info *cfv = netdev_priv(netdev);
|
|
if (cfv_create_genpool(cfv))
|
return -ENOMEM;
|
|
netif_carrier_on(netdev);
|
napi_enable(&cfv->napi);
|
|
/* Schedule NAPI to read any pending packets */
|
napi_schedule(&cfv->napi);
|
return 0;
|
}
|
|
/* Disable the CAIF interface and free the memory-pool */
|
static int cfv_netdev_close(struct net_device *netdev)
|
{
|
struct cfv_info *cfv = netdev_priv(netdev);
|
unsigned long flags;
|
struct buf_info *buf_info;
|
|
/* Disable interrupts, queues and NAPI polling */
|
netif_carrier_off(netdev);
|
virtqueue_disable_cb(cfv->vq_tx);
|
vringh_notify_disable_kern(cfv->vr_rx);
|
napi_disable(&cfv->napi);
|
|
/* Release any TX buffers on both used and avilable rings */
|
cfv_release_used_buf(cfv->vq_tx);
|
spin_lock_irqsave(&cfv->tx_lock, flags);
|
while ((buf_info = virtqueue_detach_unused_buf(cfv->vq_tx)))
|
free_buf_info(cfv, buf_info);
|
spin_unlock_irqrestore(&cfv->tx_lock, flags);
|
|
/* Release all dma allocated memory and destroy the pool */
|
cfv_destroy_genpool(cfv);
|
return 0;
|
}
|
|
/* Allocate a buffer in dma-memory and copy skb to it */
|
static struct buf_info *cfv_alloc_and_copy_to_shm(struct cfv_info *cfv,
|
struct sk_buff *skb,
|
struct scatterlist *sg)
|
{
|
struct caif_payload_info *info = (void *)&skb->cb;
|
struct buf_info *buf_info = NULL;
|
u8 pad_len, hdr_ofs;
|
|
if (!cfv->genpool)
|
goto err;
|
|
if (unlikely(cfv->tx_hr + skb->len + cfv->tx_tr > cfv->mtu)) {
|
netdev_warn(cfv->ndev, "Invalid packet len (%d > %d)\n",
|
cfv->tx_hr + skb->len + cfv->tx_tr, cfv->mtu);
|
goto err;
|
}
|
|
buf_info = kmalloc(sizeof(struct buf_info), GFP_ATOMIC);
|
if (unlikely(!buf_info))
|
goto err;
|
|
/* Make the IP header aligned in tbe buffer */
|
hdr_ofs = cfv->tx_hr + info->hdr_len;
|
pad_len = hdr_ofs & (IP_HDR_ALIGN - 1);
|
buf_info->size = cfv->tx_hr + skb->len + cfv->tx_tr + pad_len;
|
|
/* allocate dma memory buffer */
|
buf_info->vaddr = (void *)gen_pool_alloc(cfv->genpool, buf_info->size);
|
if (unlikely(!buf_info->vaddr))
|
goto err;
|
|
/* copy skbuf contents to send buffer */
|
skb_copy_bits(skb, 0, buf_info->vaddr + cfv->tx_hr + pad_len, skb->len);
|
sg_init_one(sg, buf_info->vaddr + pad_len,
|
skb->len + cfv->tx_hr + cfv->rx_hr);
|
|
return buf_info;
|
err:
|
kfree(buf_info);
|
return NULL;
|
}
|
|
/* Put the CAIF packet on the virtio ring and kick the receiver */
|
static int cfv_netdev_tx(struct sk_buff *skb, struct net_device *netdev)
|
{
|
struct cfv_info *cfv = netdev_priv(netdev);
|
struct buf_info *buf_info;
|
struct scatterlist sg;
|
unsigned long flags;
|
bool flow_off = false;
|
int ret;
|
|
/* garbage collect released buffers */
|
cfv_release_used_buf(cfv->vq_tx);
|
spin_lock_irqsave(&cfv->tx_lock, flags);
|
|
/* Flow-off check takes into account number of cpus to make sure
|
* virtqueue will not be overfilled in any possible smp conditions.
|
*
|
* Flow-on is triggered when sufficient buffers are freed
|
*/
|
if (unlikely(cfv->vq_tx->num_free <= num_present_cpus())) {
|
flow_off = true;
|
cfv->stats.tx_full_ring++;
|
}
|
|
/* If we run out of memory, we release the memory reserve and retry
|
* allocation.
|
*/
|
buf_info = cfv_alloc_and_copy_to_shm(cfv, skb, &sg);
|
if (unlikely(!buf_info)) {
|
cfv->stats.tx_no_mem++;
|
flow_off = true;
|
|
if (cfv->reserved_mem && cfv->genpool) {
|
gen_pool_free(cfv->genpool, cfv->reserved_mem,
|
cfv->reserved_size);
|
cfv->reserved_mem = 0;
|
buf_info = cfv_alloc_and_copy_to_shm(cfv, skb, &sg);
|
}
|
}
|
|
if (unlikely(flow_off)) {
|
/* Turn flow on when a 1/4 of the descriptors are released */
|
cfv->watermark_tx = virtqueue_get_vring_size(cfv->vq_tx) / 4;
|
/* Enable notifications of recycled TX buffers */
|
virtqueue_enable_cb(cfv->vq_tx);
|
netif_tx_stop_all_queues(netdev);
|
}
|
|
if (unlikely(!buf_info)) {
|
/* If the memory reserve does it's job, this shouldn't happen */
|
netdev_warn(cfv->ndev, "Out of gen_pool memory\n");
|
goto err;
|
}
|
|
ret = virtqueue_add_outbuf(cfv->vq_tx, &sg, 1, buf_info, GFP_ATOMIC);
|
if (unlikely((ret < 0))) {
|
/* If flow control works, this shouldn't happen */
|
netdev_warn(cfv->ndev, "Failed adding buffer to TX vring:%d\n",
|
ret);
|
goto err;
|
}
|
|
/* update netdev statistics */
|
cfv->ndev->stats.tx_packets++;
|
cfv->ndev->stats.tx_bytes += skb->len;
|
spin_unlock_irqrestore(&cfv->tx_lock, flags);
|
|
/* tell the remote processor it has a pending message to read */
|
virtqueue_kick(cfv->vq_tx);
|
|
dev_kfree_skb(skb);
|
return NETDEV_TX_OK;
|
err:
|
spin_unlock_irqrestore(&cfv->tx_lock, flags);
|
cfv->ndev->stats.tx_dropped++;
|
free_buf_info(cfv, buf_info);
|
dev_kfree_skb(skb);
|
return NETDEV_TX_OK;
|
}
|
|
static void cfv_tx_release_tasklet(unsigned long drv)
|
{
|
struct cfv_info *cfv = (struct cfv_info *)drv;
|
cfv_release_used_buf(cfv->vq_tx);
|
}
|
|
static const struct net_device_ops cfv_netdev_ops = {
|
.ndo_open = cfv_netdev_open,
|
.ndo_stop = cfv_netdev_close,
|
.ndo_start_xmit = cfv_netdev_tx,
|
};
|
|
static void cfv_netdev_setup(struct net_device *netdev)
|
{
|
netdev->netdev_ops = &cfv_netdev_ops;
|
netdev->type = ARPHRD_CAIF;
|
netdev->tx_queue_len = 100;
|
netdev->flags = IFF_POINTOPOINT | IFF_NOARP;
|
netdev->mtu = CFV_DEF_MTU_SIZE;
|
netdev->needs_free_netdev = true;
|
}
|
|
/* Create debugfs counters for the device */
|
static inline void debugfs_init(struct cfv_info *cfv)
|
{
|
cfv->debugfs =
|
debugfs_create_dir(netdev_name(cfv->ndev), NULL);
|
|
if (IS_ERR(cfv->debugfs))
|
return;
|
|
debugfs_create_u32("rx-napi-complete", 0400, cfv->debugfs,
|
&cfv->stats.rx_napi_complete);
|
debugfs_create_u32("rx-napi-resched", 0400, cfv->debugfs,
|
&cfv->stats.rx_napi_resched);
|
debugfs_create_u32("rx-nomem", 0400, cfv->debugfs,
|
&cfv->stats.rx_nomem);
|
debugfs_create_u32("rx-kicks", 0400, cfv->debugfs,
|
&cfv->stats.rx_kicks);
|
debugfs_create_u32("tx-full-ring", 0400, cfv->debugfs,
|
&cfv->stats.tx_full_ring);
|
debugfs_create_u32("tx-no-mem", 0400, cfv->debugfs,
|
&cfv->stats.tx_no_mem);
|
debugfs_create_u32("tx-kicks", 0400, cfv->debugfs,
|
&cfv->stats.tx_kicks);
|
debugfs_create_u32("tx-flow-on", 0400, cfv->debugfs,
|
&cfv->stats.tx_flow_on);
|
}
|
|
/* Setup CAIF for the a virtio device */
|
static int cfv_probe(struct virtio_device *vdev)
|
{
|
vq_callback_t *vq_cbs = cfv_release_cb;
|
vrh_callback_t *vrh_cbs = cfv_recv;
|
const char *names = "output";
|
const char *cfv_netdev_name = "cfvrt";
|
struct net_device *netdev;
|
struct cfv_info *cfv;
|
int err = -EINVAL;
|
|
netdev = alloc_netdev(sizeof(struct cfv_info), cfv_netdev_name,
|
NET_NAME_UNKNOWN, cfv_netdev_setup);
|
if (!netdev)
|
return -ENOMEM;
|
|
cfv = netdev_priv(netdev);
|
cfv->vdev = vdev;
|
cfv->ndev = netdev;
|
|
spin_lock_init(&cfv->tx_lock);
|
|
/* Get the RX virtio ring. This is a "host side vring". */
|
err = -ENODEV;
|
if (!vdev->vringh_config || !vdev->vringh_config->find_vrhs)
|
goto err;
|
|
err = vdev->vringh_config->find_vrhs(vdev, 1, &cfv->vr_rx, &vrh_cbs);
|
if (err)
|
goto err;
|
|
/* Get the TX virtio ring. This is a "guest side vring". */
|
err = virtio_find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs, &names, NULL);
|
if (err)
|
goto err;
|
|
/* Get the CAIF configuration from virtio config space, if available */
|
if (vdev->config->get) {
|
virtio_cread(vdev, struct virtio_caif_transf_config, headroom,
|
&cfv->tx_hr);
|
virtio_cread(vdev, struct virtio_caif_transf_config, headroom,
|
&cfv->rx_hr);
|
virtio_cread(vdev, struct virtio_caif_transf_config, tailroom,
|
&cfv->tx_tr);
|
virtio_cread(vdev, struct virtio_caif_transf_config, tailroom,
|
&cfv->rx_tr);
|
virtio_cread(vdev, struct virtio_caif_transf_config, mtu,
|
&cfv->mtu);
|
virtio_cread(vdev, struct virtio_caif_transf_config, mtu,
|
&cfv->mru);
|
} else {
|
cfv->tx_hr = CFV_DEF_HEADROOM;
|
cfv->rx_hr = CFV_DEF_HEADROOM;
|
cfv->tx_tr = CFV_DEF_TAILROOM;
|
cfv->rx_tr = CFV_DEF_TAILROOM;
|
cfv->mtu = CFV_DEF_MTU_SIZE;
|
cfv->mru = CFV_DEF_MTU_SIZE;
|
}
|
|
netdev->needed_headroom = cfv->tx_hr;
|
netdev->needed_tailroom = cfv->tx_tr;
|
|
/* Disable buffer release interrupts unless we have stopped TX queues */
|
virtqueue_disable_cb(cfv->vq_tx);
|
|
netdev->mtu = cfv->mtu - cfv->tx_tr;
|
vdev->priv = cfv;
|
|
/* Initialize NAPI poll context data */
|
vringh_kiov_init(&cfv->ctx.riov, NULL, 0);
|
cfv->ctx.head = USHRT_MAX;
|
netif_napi_add(netdev, &cfv->napi, cfv_rx_poll, CFV_DEFAULT_QUOTA);
|
|
tasklet_init(&cfv->tx_release_tasklet,
|
cfv_tx_release_tasklet,
|
(unsigned long)cfv);
|
|
/* Carrier is off until netdevice is opened */
|
netif_carrier_off(netdev);
|
|
/* register Netdev */
|
err = register_netdev(netdev);
|
if (err) {
|
dev_err(&vdev->dev, "Unable to register netdev (%d)\n", err);
|
goto err;
|
}
|
|
debugfs_init(cfv);
|
|
return 0;
|
err:
|
netdev_warn(cfv->ndev, "CAIF Virtio probe failed:%d\n", err);
|
|
if (cfv->vr_rx)
|
vdev->vringh_config->del_vrhs(cfv->vdev);
|
if (cfv->vdev)
|
vdev->config->del_vqs(cfv->vdev);
|
free_netdev(netdev);
|
return err;
|
}
|
|
static void cfv_remove(struct virtio_device *vdev)
|
{
|
struct cfv_info *cfv = vdev->priv;
|
|
rtnl_lock();
|
dev_close(cfv->ndev);
|
rtnl_unlock();
|
|
tasklet_kill(&cfv->tx_release_tasklet);
|
debugfs_remove_recursive(cfv->debugfs);
|
|
vringh_kiov_cleanup(&cfv->ctx.riov);
|
vdev->config->reset(vdev);
|
vdev->vringh_config->del_vrhs(cfv->vdev);
|
cfv->vr_rx = NULL;
|
vdev->config->del_vqs(cfv->vdev);
|
unregister_netdev(cfv->ndev);
|
}
|
|
static struct virtio_device_id id_table[] = {
|
{ VIRTIO_ID_CAIF, VIRTIO_DEV_ANY_ID },
|
{ 0 },
|
};
|
|
static unsigned int features[] = {
|
};
|
|
static struct virtio_driver caif_virtio_driver = {
|
.feature_table = features,
|
.feature_table_size = ARRAY_SIZE(features),
|
.driver.name = KBUILD_MODNAME,
|
.driver.owner = THIS_MODULE,
|
.id_table = id_table,
|
.probe = cfv_probe,
|
.remove = cfv_remove,
|
};
|
|
module_virtio_driver(caif_virtio_driver);
|
MODULE_DEVICE_TABLE(virtio, id_table);
|
