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kernel/arch/um/drivers/vector_kern.c

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/*
* Copyright (C) 2017 - Cambridge Greys Limited
* Copyright (C) 2011 - 2014 Cisco Systems Inc
* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
* James Leu (jleu@mindspring.net).
* Copyright (C) 2001 by various other people who didn't put their name here.
* Licensed under the GPL.
*/
#include <linux/version.h>
#include <linux/memblock.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/inetdevice.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/platform_device.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <init.h>
#include <irq_kern.h>
#include <irq_user.h>
#include <net_kern.h>
#include <os.h>
#include "mconsole_kern.h"
#include "vector_user.h"
#include "vector_kern.h"
/*
* Adapted from network devices with the following major changes:
* All transports are static - simplifies the code significantly
* Multiple FDs/IRQs per device
* Vector IO optionally used for read/write, falling back to legacy
* based on configuration and/or availability
* Configuration is no longer positional - L2TPv3 and GRE require up to
* 10 parameters, passing this as positional is not fit for purpose.
* Only socket transports are supported
*/
#define DRIVER_NAME "uml-vector"
#define DRIVER_VERSION "01"
struct vector_cmd_line_arg {
struct list_head list;
int unit;
char *arguments;
};
struct vector_device {
struct list_head list;
struct net_device *dev;
struct platform_device pdev;
int unit;
int opened;
};
static LIST_HEAD(vec_cmd_line);
static DEFINE_SPINLOCK(vector_devices_lock);
static LIST_HEAD(vector_devices);
static int driver_registered;
static void vector_eth_configure(int n, struct arglist *def);
/* Argument accessors to set variables (and/or set default values)
* mtu, buffer sizing, default headroom, etc
*/
#define DEFAULT_HEADROOM 2
#define SAFETY_MARGIN 32
#define DEFAULT_VECTOR_SIZE 64
#define TX_SMALL_PACKET 128
#define MAX_IOV_SIZE (MAX_SKB_FRAGS + 1)
static const struct {
const char string[ETH_GSTRING_LEN];
} ethtool_stats_keys[] = {
{ "rx_queue_max" },
{ "rx_queue_running_average" },
{ "tx_queue_max" },
{ "tx_queue_running_average" },
{ "rx_encaps_errors" },
{ "tx_timeout_count" },
{ "tx_restart_queue" },
{ "tx_kicks" },
{ "tx_flow_control_xon" },
{ "tx_flow_control_xoff" },
{ "rx_csum_offload_good" },
{ "rx_csum_offload_errors"},
{ "sg_ok"},
{ "sg_linearized"},
};
#define VECTOR_NUM_STATS ARRAY_SIZE(ethtool_stats_keys)
static void vector_reset_stats(struct vector_private *vp)
{
vp->estats.rx_queue_max = 0;
vp->estats.rx_queue_running_average = 0;
vp->estats.tx_queue_max = 0;
vp->estats.tx_queue_running_average = 0;
vp->estats.rx_encaps_errors = 0;
vp->estats.tx_timeout_count = 0;
vp->estats.tx_restart_queue = 0;
vp->estats.tx_kicks = 0;
vp->estats.tx_flow_control_xon = 0;
vp->estats.tx_flow_control_xoff = 0;
vp->estats.sg_ok = 0;
vp->estats.sg_linearized = 0;
}
static int get_mtu(struct arglist *def)
{
char *mtu = uml_vector_fetch_arg(def, "mtu");
long result;
if (mtu != NULL) {
if (kstrtoul(mtu, 10, &result) == 0)
return result;
}
return ETH_MAX_PACKET;
}
static int get_depth(struct arglist *def)
{
char *mtu = uml_vector_fetch_arg(def, "depth");
long result;
if (mtu != NULL) {
if (kstrtoul(mtu, 10, &result) == 0)
return result;
}
return DEFAULT_VECTOR_SIZE;
}
static int get_headroom(struct arglist *def)
{
char *mtu = uml_vector_fetch_arg(def, "headroom");
long result;
if (mtu != NULL) {
if (kstrtoul(mtu, 10, &result) == 0)
return result;
}
return DEFAULT_HEADROOM;
}
static int get_req_size(struct arglist *def)
{
char *gro = uml_vector_fetch_arg(def, "gro");
long result;
if (gro != NULL) {
if (kstrtoul(gro, 10, &result) == 0) {
if (result > 0)
return 65536;
}
}
return get_mtu(def) + ETH_HEADER_OTHER +
get_headroom(def) + SAFETY_MARGIN;
}
static int get_transport_options(struct arglist *def)
{
char *transport = uml_vector_fetch_arg(def, "transport");
char *vector = uml_vector_fetch_arg(def, "vec");
int vec_rx = VECTOR_RX;
int vec_tx = VECTOR_TX;
long parsed;
if (vector != NULL) {
if (kstrtoul(vector, 10, &parsed) == 0) {
if (parsed == 0) {
vec_rx = 0;
vec_tx = 0;
}
}
}
if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0)
return (vec_rx | VECTOR_BPF);
if (strncmp(transport, TRANS_RAW, TRANS_RAW_LEN) == 0)
return (vec_rx | vec_tx | VECTOR_QDISC_BYPASS);
return (vec_rx | vec_tx);
}
/* A mini-buffer for packet drop read
* All of our supported transports are datagram oriented and we always
* read using recvmsg or recvmmsg. If we pass a buffer which is smaller
* than the packet size it still counts as full packet read and will
* clean the incoming stream to keep sigio/epoll happy
*/
#define DROP_BUFFER_SIZE 32
static char *drop_buffer;
/* Array backed queues optimized for bulk enqueue/dequeue and
* 1:N (small values of N) or 1:1 enqueuer/dequeuer ratios.
* For more details and full design rationale see
* http://foswiki.cambridgegreys.com/Main/EatYourTailAndEnjoyIt
*/
/*
* Advance the mmsg queue head by n = advance. Resets the queue to
* maximum enqueue/dequeue-at-once capacity if possible. Called by
* dequeuers. Caller must hold the head_lock!
*/
static int vector_advancehead(struct vector_queue *qi, int advance)
{
int queue_depth;
qi->head =
(qi->head + advance)
% qi->max_depth;
spin_lock(&qi->tail_lock);
qi->queue_depth -= advance;
/* we are at 0, use this to
* reset head and tail so we can use max size vectors
*/
if (qi->queue_depth == 0) {
qi->head = 0;
qi->tail = 0;
}
queue_depth = qi->queue_depth;
spin_unlock(&qi->tail_lock);
return queue_depth;
}
/* Advance the queue tail by n = advance.
* This is called by enqueuers which should hold the
* head lock already
*/
static int vector_advancetail(struct vector_queue *qi, int advance)
{
int queue_depth;
qi->tail =
(qi->tail + advance)
% qi->max_depth;
spin_lock(&qi->head_lock);
qi->queue_depth += advance;
queue_depth = qi->queue_depth;
spin_unlock(&qi->head_lock);
return queue_depth;
}
static int prep_msg(struct vector_private *vp,
struct sk_buff *skb,
struct iovec *iov)
{
int iov_index = 0;
int nr_frags, frag;
skb_frag_t *skb_frag;
nr_frags = skb_shinfo(skb)->nr_frags;
if (nr_frags > MAX_IOV_SIZE) {
if (skb_linearize(skb) != 0)
goto drop;
}
if (vp->header_size > 0) {
iov[iov_index].iov_len = vp->header_size;
vp->form_header(iov[iov_index].iov_base, skb, vp);
iov_index++;
}
iov[iov_index].iov_base = skb->data;
if (nr_frags > 0) {
iov[iov_index].iov_len = skb->len - skb->data_len;
vp->estats.sg_ok++;
} else
iov[iov_index].iov_len = skb->len;
iov_index++;
for (frag = 0; frag < nr_frags; frag++) {
skb_frag = &skb_shinfo(skb)->frags[frag];
iov[iov_index].iov_base = skb_frag_address_safe(skb_frag);
iov[iov_index].iov_len = skb_frag_size(skb_frag);
iov_index++;
}
return iov_index;
drop:
return -1;
}
/*
* Generic vector enqueue with support for forming headers using transport
* specific callback. Allows GRE, L2TPv3, RAW and other transports
* to use a common enqueue procedure in vector mode
*/
static int vector_enqueue(struct vector_queue *qi, struct sk_buff *skb)
{
struct vector_private *vp = netdev_priv(qi->dev);
int queue_depth;
int packet_len;
struct mmsghdr *mmsg_vector = qi->mmsg_vector;
int iov_count;
spin_lock(&qi->tail_lock);
spin_lock(&qi->head_lock);
queue_depth = qi->queue_depth;
spin_unlock(&qi->head_lock);
if (skb)
packet_len = skb->len;
if (queue_depth < qi->max_depth) {
*(qi->skbuff_vector + qi->tail) = skb;
mmsg_vector += qi->tail;
iov_count = prep_msg(
vp,
skb,
mmsg_vector->msg_hdr.msg_iov
);
if (iov_count < 1)
goto drop;
mmsg_vector->msg_hdr.msg_iovlen = iov_count;
mmsg_vector->msg_hdr.msg_name = vp->fds->remote_addr;
mmsg_vector->msg_hdr.msg_namelen = vp->fds->remote_addr_size;
queue_depth = vector_advancetail(qi, 1);
} else
goto drop;
spin_unlock(&qi->tail_lock);
return queue_depth;
drop:
qi->dev->stats.tx_dropped++;
if (skb != NULL) {
packet_len = skb->len;
dev_consume_skb_any(skb);
netdev_completed_queue(qi->dev, 1, packet_len);
}
spin_unlock(&qi->tail_lock);
return queue_depth;
}
static int consume_vector_skbs(struct vector_queue *qi, int count)
{
struct sk_buff *skb;
int skb_index;
int bytes_compl = 0;
for (skb_index = qi->head; skb_index < qi->head + count; skb_index++) {
skb = *(qi->skbuff_vector + skb_index);
/* mark as empty to ensure correct destruction if
* needed
*/
bytes_compl += skb->len;
*(qi->skbuff_vector + skb_index) = NULL;
dev_consume_skb_any(skb);
}
qi->dev->stats.tx_bytes += bytes_compl;
qi->dev->stats.tx_packets += count;
netdev_completed_queue(qi->dev, count, bytes_compl);
return vector_advancehead(qi, count);
}
/*
* Generic vector deque via sendmmsg with support for forming headers
* using transport specific callback. Allows GRE, L2TPv3, RAW and
* other transports to use a common dequeue procedure in vector mode
*/
static int vector_send(struct vector_queue *qi)
{
struct vector_private *vp = netdev_priv(qi->dev);
struct mmsghdr *send_from;
int result = 0, send_len, queue_depth = qi->max_depth;
if (spin_trylock(&qi->head_lock)) {
if (spin_trylock(&qi->tail_lock)) {
/* update queue_depth to current value */
queue_depth = qi->queue_depth;
spin_unlock(&qi->tail_lock);
while (queue_depth > 0) {
/* Calculate the start of the vector */
send_len = queue_depth;
send_from = qi->mmsg_vector;
send_from += qi->head;
/* Adjust vector size if wraparound */
if (send_len + qi->head > qi->max_depth)
send_len = qi->max_depth - qi->head;
/* Try to TX as many packets as possible */
if (send_len > 0) {
result = uml_vector_sendmmsg(
vp->fds->tx_fd,
send_from,
send_len,
0
);
vp->in_write_poll =
(result != send_len);
}
/* For some of the sendmmsg error scenarios
* we may end being unsure in the TX success
* for all packets. It is safer to declare
* them all TX-ed and blame the network.
*/
if (result < 0) {
if (net_ratelimit())
netdev_err(vp->dev, "sendmmsg err=%i\n",
result);
result = send_len;
}
if (result > 0) {
queue_depth =
consume_vector_skbs(qi, result);
/* This is equivalent to an TX IRQ.
* Restart the upper layers to feed us
* more packets.
*/
if (result > vp->estats.tx_queue_max)
vp->estats.tx_queue_max = result;
vp->estats.tx_queue_running_average =
(vp->estats.tx_queue_running_average + result) >> 1;
}
netif_trans_update(qi->dev);
netif_wake_queue(qi->dev);
/* if TX is busy, break out of the send loop,
* poll write IRQ will reschedule xmit for us
*/
if (result != send_len) {
vp->estats.tx_restart_queue++;
break;
}
}
}
spin_unlock(&qi->head_lock);
} else {
tasklet_schedule(&vp->tx_poll);
}
return queue_depth;
}
/* Queue destructor. Deliberately stateless so we can use
* it in queue cleanup if initialization fails.
*/
static void destroy_queue(struct vector_queue *qi)
{
int i;
struct iovec *iov;
struct vector_private *vp = netdev_priv(qi->dev);
struct mmsghdr *mmsg_vector;
if (qi == NULL)
return;
/* deallocate any skbuffs - we rely on any unused to be
* set to NULL.
*/
if (qi->skbuff_vector != NULL) {
for (i = 0; i < qi->max_depth; i++) {
if (*(qi->skbuff_vector + i) != NULL)
dev_kfree_skb_any(*(qi->skbuff_vector + i));
}
kfree(qi->skbuff_vector);
}
/* deallocate matching IOV structures including header buffs */
if (qi->mmsg_vector != NULL) {
mmsg_vector = qi->mmsg_vector;
for (i = 0; i < qi->max_depth; i++) {
iov = mmsg_vector->msg_hdr.msg_iov;
if (iov != NULL) {
if ((vp->header_size > 0) &&
(iov->iov_base != NULL))
kfree(iov->iov_base);
kfree(iov);
}
mmsg_vector++;
}
kfree(qi->mmsg_vector);
}
kfree(qi);
}
/*
* Queue constructor. Create a queue with a given side.
*/
static struct vector_queue *create_queue(
struct vector_private *vp,
int max_size,
int header_size,
int num_extra_frags)
{
struct vector_queue *result;
int i;
struct iovec *iov;
struct mmsghdr *mmsg_vector;
result = kmalloc(sizeof(struct vector_queue), GFP_KERNEL);
if (result == NULL)
return NULL;
result->max_depth = max_size;
result->dev = vp->dev;
result->mmsg_vector = kmalloc(
(sizeof(struct mmsghdr) * max_size), GFP_KERNEL);
if (result->mmsg_vector == NULL)
goto out_mmsg_fail;
result->skbuff_vector = kmalloc(
(sizeof(void *) * max_size), GFP_KERNEL);
if (result->skbuff_vector == NULL)
goto out_skb_fail;
/* further failures can be handled safely by destroy_queue*/
mmsg_vector = result->mmsg_vector;
for (i = 0; i < max_size; i++) {
/* Clear all pointers - we use non-NULL as marking on
* what to free on destruction
*/
*(result->skbuff_vector + i) = NULL;
mmsg_vector->msg_hdr.msg_iov = NULL;
mmsg_vector++;
}
mmsg_vector = result->mmsg_vector;
result->max_iov_frags = num_extra_frags;
for (i = 0; i < max_size; i++) {
if (vp->header_size > 0)
iov = kmalloc_array(3 + num_extra_frags,
sizeof(struct iovec),
GFP_KERNEL
);
else
iov = kmalloc_array(2 + num_extra_frags,
sizeof(struct iovec),
GFP_KERNEL
);
if (iov == NULL)
goto out_fail;
mmsg_vector->msg_hdr.msg_iov = iov;
mmsg_vector->msg_hdr.msg_iovlen = 1;
mmsg_vector->msg_hdr.msg_control = NULL;
mmsg_vector->msg_hdr.msg_controllen = 0;
mmsg_vector->msg_hdr.msg_flags = MSG_DONTWAIT;
mmsg_vector->msg_hdr.msg_name = NULL;
mmsg_vector->msg_hdr.msg_namelen = 0;
if (vp->header_size > 0) {
iov->iov_base = kmalloc(header_size, GFP_KERNEL);
if (iov->iov_base == NULL)
goto out_fail;
iov->iov_len = header_size;
mmsg_vector->msg_hdr.msg_iovlen = 2;
iov++;
}
iov->iov_base = NULL;
iov->iov_len = 0;
mmsg_vector++;
}
spin_lock_init(&result->head_lock);
spin_lock_init(&result->tail_lock);
result->queue_depth = 0;
result->head = 0;
result->tail = 0;
return result;
out_skb_fail:
kfree(result->mmsg_vector);
out_mmsg_fail:
kfree(result);
return NULL;
out_fail:
destroy_queue(result);
return NULL;
}
/*
* We do not use the RX queue as a proper wraparound queue for now
* This is not necessary because the consumption via netif_rx()
* happens in-line. While we can try using the return code of
* netif_rx() for flow control there are no drivers doing this today.
* For this RX specific use we ignore the tail/head locks and
* just read into a prepared queue filled with skbuffs.
*/
static struct sk_buff *prep_skb(
struct vector_private *vp,
struct user_msghdr *msg)
{
int linear = vp->max_packet + vp->headroom + SAFETY_MARGIN;
struct sk_buff *result;
int iov_index = 0, len;
struct iovec *iov = msg->msg_iov;
int err, nr_frags, frag;
skb_frag_t *skb_frag;
if (vp->req_size <= linear)
len = linear;
else
len = vp->req_size;
result = alloc_skb_with_frags(
linear,
len - vp->max_packet,
3,
&err,
GFP_ATOMIC
);
if (vp->header_size > 0)
iov_index++;
if (result == NULL) {
iov[iov_index].iov_base = NULL;
iov[iov_index].iov_len = 0;
goto done;
}
skb_reserve(result, vp->headroom);
result->dev = vp->dev;
skb_put(result, vp->max_packet);
result->data_len = len - vp->max_packet;
result->len += len - vp->max_packet;
skb_reset_mac_header(result);
result->ip_summed = CHECKSUM_NONE;
iov[iov_index].iov_base = result->data;
iov[iov_index].iov_len = vp->max_packet;
iov_index++;
nr_frags = skb_shinfo(result)->nr_frags;
for (frag = 0; frag < nr_frags; frag++) {
skb_frag = &skb_shinfo(result)->frags[frag];
iov[iov_index].iov_base = skb_frag_address_safe(skb_frag);
if (iov[iov_index].iov_base != NULL)
iov[iov_index].iov_len = skb_frag_size(skb_frag);
else
iov[iov_index].iov_len = 0;
iov_index++;
}
done:
msg->msg_iovlen = iov_index;
return result;
}
/* Prepare queue for recvmmsg one-shot rx - fill with fresh sk_buffs*/
static void prep_queue_for_rx(struct vector_queue *qi)
{
struct vector_private *vp = netdev_priv(qi->dev);
struct mmsghdr *mmsg_vector = qi->mmsg_vector;
void **skbuff_vector = qi->skbuff_vector;
int i;
if (qi->queue_depth == 0)
return;
for (i = 0; i < qi->queue_depth; i++) {
/* it is OK if allocation fails - recvmmsg with NULL data in
* iov argument still performs an RX, just drops the packet
* This allows us stop faffing around with a "drop buffer"
*/
*skbuff_vector = prep_skb(vp, &mmsg_vector->msg_hdr);
skbuff_vector++;
mmsg_vector++;
}
qi->queue_depth = 0;
}
static struct vector_device *find_device(int n)
{
struct vector_device *device;
struct list_head *ele;
spin_lock(&vector_devices_lock);
list_for_each(ele, &vector_devices) {
device = list_entry(ele, struct vector_device, list);
if (device->unit == n)
goto out;
}
device = NULL;
out:
spin_unlock(&vector_devices_lock);
return device;
}
static int vector_parse(char *str, int *index_out, char **str_out,
char **error_out)
{
int n, len, err;
char *start = str;
len = strlen(str);
while ((*str != ':') && (strlen(str) > 1))
str++;
if (*str != ':') {
*error_out = "Expected ':' after device number";
return -EINVAL;
}
*str = '\0';
err = kstrtouint(start, 0, &n);
if (err < 0) {
*error_out = "Bad device number";
return err;
}
str++;
if (find_device(n)) {
*error_out = "Device already configured";
return -EINVAL;
}
*index_out = n;
*str_out = str;
return 0;
}
static int vector_config(char *str, char **error_out)
{
int err, n;
char *params;
struct arglist *parsed;
err = vector_parse(str, &n, &params, error_out);
if (err != 0)
return err;
/* This string is broken up and the pieces used by the underlying
* driver. We should copy it to make sure things do not go wrong
* later.
*/
params = kstrdup(params, GFP_KERNEL);
if (params == NULL) {
*error_out = "vector_config failed to strdup string";
return -ENOMEM;
}
parsed = uml_parse_vector_ifspec(params);
if (parsed == NULL) {
*error_out = "vector_config failed to parse parameters";
return -EINVAL;
}
vector_eth_configure(n, parsed);
return 0;
}
static int vector_id(char **str, int *start_out, int *end_out)
{
char *end;
int n;
n = simple_strtoul(*str, &end, 0);
if ((*end != '\0') || (end == *str))
return -1;
*start_out = n;
*end_out = n;
*str = end;
return n;
}
static int vector_remove(int n, char **error_out)
{
struct vector_device *vec_d;
struct net_device *dev;
struct vector_private *vp;
vec_d = find_device(n);
if (vec_d == NULL)
return -ENODEV;
dev = vec_d->dev;
vp = netdev_priv(dev);
if (vp->fds != NULL)
return -EBUSY;
unregister_netdev(dev);
platform_device_unregister(&vec_d->pdev);
return 0;
}
/*
* There is no shared per-transport initialization code, so
* we will just initialize each interface one by one and
* add them to a list
*/
static struct platform_driver uml_net_driver = {
.driver = {
.name = DRIVER_NAME,
},
};
static void vector_device_release(struct device *dev)
{
struct vector_device *device = dev_get_drvdata(dev);
struct net_device *netdev = device->dev;
list_del(&device->list);
kfree(device);
free_netdev(netdev);
}
/* Bog standard recv using recvmsg - not used normally unless the user
* explicitly specifies not to use recvmmsg vector RX.
*/
static int vector_legacy_rx(struct vector_private *vp)
{
int pkt_len;
struct user_msghdr hdr;
struct iovec iov[2 + MAX_IOV_SIZE]; /* header + data use case only */
int iovpos = 0;
struct sk_buff *skb;
int header_check;
hdr.msg_name = NULL;
hdr.msg_namelen = 0;
hdr.msg_iov = (struct iovec *) &iov;
hdr.msg_control = NULL;
hdr.msg_controllen = 0;
hdr.msg_flags = 0;
if (vp->header_size > 0) {
iov[0].iov_base = vp->header_rxbuffer;
iov[0].iov_len = vp->header_size;
}
skb = prep_skb(vp, &hdr);
if (skb == NULL) {
/* Read a packet into drop_buffer and don't do
* anything with it.
*/
iov[iovpos].iov_base = drop_buffer;
iov[iovpos].iov_len = DROP_BUFFER_SIZE;
hdr.msg_iovlen = 1;
vp->dev->stats.rx_dropped++;
}
pkt_len = uml_vector_recvmsg(vp->fds->rx_fd, &hdr, 0);
if (skb != NULL) {
if (pkt_len > vp->header_size) {
if (vp->header_size > 0) {
header_check = vp->verify_header(
vp->header_rxbuffer, skb, vp);
if (header_check < 0) {
dev_kfree_skb_irq(skb);
vp->dev->stats.rx_dropped++;
vp->estats.rx_encaps_errors++;
return 0;
}
if (header_check > 0) {
vp->estats.rx_csum_offload_good++;
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
}
pskb_trim(skb, pkt_len - vp->rx_header_size);
skb->protocol = eth_type_trans(skb, skb->dev);
vp->dev->stats.rx_bytes += skb->len;
vp->dev->stats.rx_packets++;
netif_rx(skb);
} else {
dev_kfree_skb_irq(skb);
}
}
return pkt_len;
}
/*
* Packet at a time TX which falls back to vector TX if the
* underlying transport is busy.
*/
static int writev_tx(struct vector_private *vp, struct sk_buff *skb)
{
struct iovec iov[3 + MAX_IOV_SIZE];
int iov_count, pkt_len = 0;
iov[0].iov_base = vp->header_txbuffer;
iov_count = prep_msg(vp, skb, (struct iovec *) &iov);
if (iov_count < 1)
goto drop;
pkt_len = uml_vector_writev(
vp->fds->tx_fd,
(struct iovec *) &iov,
iov_count
);
netif_trans_update(vp->dev);
netif_wake_queue(vp->dev);
if (pkt_len > 0) {
vp->dev->stats.tx_bytes += skb->len;
vp->dev->stats.tx_packets++;
} else {
vp->dev->stats.tx_dropped++;
}
consume_skb(skb);
return pkt_len;
drop:
vp->dev->stats.tx_dropped++;
consume_skb(skb);
return pkt_len;
}
/*
* Receive as many messages as we can in one call using the special
* mmsg vector matched to an skb vector which we prepared earlier.
*/
static int vector_mmsg_rx(struct vector_private *vp)
{
int packet_count, i;
struct vector_queue *qi = vp->rx_queue;
struct sk_buff *skb;
struct mmsghdr *mmsg_vector = qi->mmsg_vector;
void **skbuff_vector = qi->skbuff_vector;
int header_check;
/* Refresh the vector and make sure it is with new skbs and the
* iovs are updated to point to them.
*/
prep_queue_for_rx(qi);
/* Fire the Lazy Gun - get as many packets as we can in one go. */
packet_count = uml_vector_recvmmsg(
vp->fds->rx_fd, qi->mmsg_vector, qi->max_depth, 0);
if (packet_count <= 0)
return packet_count;
/* We treat packet processing as enqueue, buffer refresh as dequeue
* The queue_depth tells us how many buffers have been used and how
* many do we need to prep the next time prep_queue_for_rx() is called.
*/
qi->queue_depth = packet_count;
for (i = 0; i < packet_count; i++) {
skb = (*skbuff_vector);
if (mmsg_vector->msg_len > vp->header_size) {
if (vp->header_size > 0) {
header_check = vp->verify_header(
mmsg_vector->msg_hdr.msg_iov->iov_base,
skb,
vp
);
if (header_check < 0) {
/* Overlay header failed to verify - discard.
* We can actually keep this skb and reuse it,
* but that will make the prep logic too
* complex.
*/
dev_kfree_skb_irq(skb);
vp->estats.rx_encaps_errors++;
continue;
}
if (header_check > 0) {
vp->estats.rx_csum_offload_good++;
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
}
pskb_trim(skb,
mmsg_vector->msg_len - vp->rx_header_size);
skb->protocol = eth_type_trans(skb, skb->dev);
/*
* We do not need to lock on updating stats here
* The interrupt loop is non-reentrant.
*/
vp->dev->stats.rx_bytes += skb->len;
vp->dev->stats.rx_packets++;
netif_rx(skb);
} else {
/* Overlay header too short to do anything - discard.
* We can actually keep this skb and reuse it,
* but that will make the prep logic too complex.
*/
if (skb != NULL)
dev_kfree_skb_irq(skb);
}
(*skbuff_vector) = NULL;
/* Move to the next buffer element */
mmsg_vector++;
skbuff_vector++;
}
if (packet_count > 0) {
if (vp->estats.rx_queue_max < packet_count)
vp->estats.rx_queue_max = packet_count;
vp->estats.rx_queue_running_average =
(vp->estats.rx_queue_running_average + packet_count) >> 1;
}
return packet_count;
}
static void vector_rx(struct vector_private *vp)
{
int err;
if ((vp->options & VECTOR_RX) > 0)
while ((err = vector_mmsg_rx(vp)) > 0)
;
else
while ((err = vector_legacy_rx(vp)) > 0)
;
if ((err != 0) && net_ratelimit())
netdev_err(vp->dev, "vector_rx: error(%d)\n", err);
}
static int vector_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct vector_private *vp = netdev_priv(dev);
int queue_depth = 0;
if ((vp->options & VECTOR_TX) == 0) {
writev_tx(vp, skb);
return NETDEV_TX_OK;
}
/* We do BQL only in the vector path, no point doing it in
* packet at a time mode as there is no device queue
*/
netdev_sent_queue(vp->dev, skb->len);
queue_depth = vector_enqueue(vp->tx_queue, skb);
/* if the device queue is full, stop the upper layers and
* flush it.
*/
if (queue_depth >= vp->tx_queue->max_depth - 1) {
vp->estats.tx_kicks++;
netif_stop_queue(dev);
vector_send(vp->tx_queue);
return NETDEV_TX_OK;
}
if (netdev_xmit_more()) {
mod_timer(&vp->tl, vp->coalesce);
return NETDEV_TX_OK;
}
if (skb->len < TX_SMALL_PACKET) {
vp->estats.tx_kicks++;
vector_send(vp->tx_queue);
} else
tasklet_schedule(&vp->tx_poll);
return NETDEV_TX_OK;
}
static irqreturn_t vector_rx_interrupt(int irq, void *dev_id)
{
struct net_device *dev = dev_id;
struct vector_private *vp = netdev_priv(dev);
if (!netif_running(dev))
return IRQ_NONE;
vector_rx(vp);
return IRQ_HANDLED;
}
static irqreturn_t vector_tx_interrupt(int irq, void *dev_id)
{
struct net_device *dev = dev_id;
struct vector_private *vp = netdev_priv(dev);
if (!netif_running(dev))
return IRQ_NONE;
/* We need to pay attention to it only if we got
* -EAGAIN or -ENOBUFFS from sendmmsg. Otherwise
* we ignore it. In the future, it may be worth
* it to improve the IRQ controller a bit to make
* tweaking the IRQ mask less costly
*/
if (vp->in_write_poll)
tasklet_schedule(&vp->tx_poll);
return IRQ_HANDLED;
}
static int irq_rr;
static int vector_net_close(struct net_device *dev)
{
struct vector_private *vp = netdev_priv(dev);
unsigned long flags;
netif_stop_queue(dev);
del_timer(&vp->tl);
if (vp->fds == NULL)
return 0;
/* Disable and free all IRQS */
if (vp->rx_irq > 0) {
um_free_irq(vp->rx_irq, dev);
vp->rx_irq = 0;
}
if (vp->tx_irq > 0) {
um_free_irq(vp->tx_irq, dev);
vp->tx_irq = 0;
}
tasklet_kill(&vp->tx_poll);
if (vp->fds->rx_fd > 0) {
os_close_file(vp->fds->rx_fd);
vp->fds->rx_fd = -1;
}
if (vp->fds->tx_fd > 0) {
os_close_file(vp->fds->tx_fd);
vp->fds->tx_fd = -1;
}
if (vp->bpf != NULL)
kfree(vp->bpf);
if (vp->fds->remote_addr != NULL)
kfree(vp->fds->remote_addr);
if (vp->transport_data != NULL)
kfree(vp->transport_data);
if (vp->header_rxbuffer != NULL)
kfree(vp->header_rxbuffer);
if (vp->header_txbuffer != NULL)
kfree(vp->header_txbuffer);
if (vp->rx_queue != NULL)
destroy_queue(vp->rx_queue);
if (vp->tx_queue != NULL)
destroy_queue(vp->tx_queue);
kfree(vp->fds);
vp->fds = NULL;
spin_lock_irqsave(&vp->lock, flags);
vp->opened = false;
spin_unlock_irqrestore(&vp->lock, flags);
return 0;
}
/* TX tasklet */
static void vector_tx_poll(unsigned long data)
{
struct vector_private *vp = (struct vector_private *)data;
vp->estats.tx_kicks++;
vector_send(vp->tx_queue);
}
static void vector_reset_tx(struct work_struct *work)
{
struct vector_private *vp =
container_of(work, struct vector_private, reset_tx);
netdev_reset_queue(vp->dev);
netif_start_queue(vp->dev);
netif_wake_queue(vp->dev);
}
static int vector_net_open(struct net_device *dev)
{
struct vector_private *vp = netdev_priv(dev);
unsigned long flags;
int err = -EINVAL;
struct vector_device *vdevice;
spin_lock_irqsave(&vp->lock, flags);
if (vp->opened) {
spin_unlock_irqrestore(&vp->lock, flags);
return -ENXIO;
}
vp->opened = true;
spin_unlock_irqrestore(&vp->lock, flags);
vp->fds = uml_vector_user_open(vp->unit, vp->parsed);
if (vp->fds == NULL)
goto out_close;
if (build_transport_data(vp) < 0)
goto out_close;
if ((vp->options & VECTOR_RX) > 0) {
vp->rx_queue = create_queue(
vp,
get_depth(vp->parsed),
vp->rx_header_size,
MAX_IOV_SIZE
);
vp->rx_queue->queue_depth = get_depth(vp->parsed);
} else {
vp->header_rxbuffer = kmalloc(
vp->rx_header_size,
GFP_KERNEL
);
if (vp->header_rxbuffer == NULL)
goto out_close;
}
if ((vp->options & VECTOR_TX) > 0) {
vp->tx_queue = create_queue(
vp,
get_depth(vp->parsed),
vp->header_size,
MAX_IOV_SIZE
);
} else {
vp->header_txbuffer = kmalloc(vp->header_size, GFP_KERNEL);
if (vp->header_txbuffer == NULL)
goto out_close;
}
/* READ IRQ */
err = um_request_irq(
irq_rr + VECTOR_BASE_IRQ, vp->fds->rx_fd,
IRQ_READ, vector_rx_interrupt,
IRQF_SHARED, dev->name, dev);
if (err != 0) {
netdev_err(dev, "vector_open: failed to get rx irq(%d)\n", err);
err = -ENETUNREACH;
goto out_close;
}
vp->rx_irq = irq_rr + VECTOR_BASE_IRQ;
dev->irq = irq_rr + VECTOR_BASE_IRQ;
irq_rr = (irq_rr + 1) % VECTOR_IRQ_SPACE;
/* WRITE IRQ - we need it only if we have vector TX */
if ((vp->options & VECTOR_TX) > 0) {
err = um_request_irq(
irq_rr + VECTOR_BASE_IRQ, vp->fds->tx_fd,
IRQ_WRITE, vector_tx_interrupt,
IRQF_SHARED, dev->name, dev);
if (err != 0) {
netdev_err(dev,
"vector_open: failed to get tx irq(%d)\n", err);
err = -ENETUNREACH;
goto out_close;
}
vp->tx_irq = irq_rr + VECTOR_BASE_IRQ;
irq_rr = (irq_rr + 1) % VECTOR_IRQ_SPACE;
}
if ((vp->options & VECTOR_QDISC_BYPASS) != 0) {
if (!uml_raw_enable_qdisc_bypass(vp->fds->rx_fd))
vp->options |= VECTOR_BPF;
}
if ((vp->options & VECTOR_BPF) != 0)
vp->bpf = uml_vector_default_bpf(vp->fds->rx_fd, dev->dev_addr);
netif_start_queue(dev);
/* clear buffer - it can happen that the host side of the interface
* is full when we get here. In this case, new data is never queued,
* SIGIOs never arrive, and the net never works.
*/
vector_rx(vp);
vector_reset_stats(vp);
vdevice = find_device(vp->unit);
vdevice->opened = 1;
if ((vp->options & VECTOR_TX) != 0)
add_timer(&vp->tl);
return 0;
out_close:
vector_net_close(dev);
return err;
}
static void vector_net_set_multicast_list(struct net_device *dev)
{
/* TODO: - we can do some BPF games here */
return;
}
static void vector_net_tx_timeout(struct net_device *dev, unsigned int txqueue)
{
struct vector_private *vp = netdev_priv(dev);
vp->estats.tx_timeout_count++;
netif_trans_update(dev);
schedule_work(&vp->reset_tx);
}
static netdev_features_t vector_fix_features(struct net_device *dev,
netdev_features_t features)
{
features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
return features;
}
static int vector_set_features(struct net_device *dev,
netdev_features_t features)
{
struct vector_private *vp = netdev_priv(dev);
/* Adjust buffer sizes for GSO/GRO. Unfortunately, there is
* no way to negotiate it on raw sockets, so we can change
* only our side.
*/
if (features & NETIF_F_GRO)
/* All new frame buffers will be GRO-sized */
vp->req_size = 65536;
else
/* All new frame buffers will be normal sized */
vp->req_size = vp->max_packet + vp->headroom + SAFETY_MARGIN;
return 0;
}
#ifdef CONFIG_NET_POLL_CONTROLLER
static void vector_net_poll_controller(struct net_device *dev)
{
disable_irq(dev->irq);
vector_rx_interrupt(dev->irq, dev);
enable_irq(dev->irq);
}
#endif
static void vector_net_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
{
strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
}
static void vector_get_ringparam(struct net_device *netdev,
struct ethtool_ringparam *ring,
struct kernel_ethtool_ringparam *kernel_ring,
struct netlink_ext_ack *extack)
{
struct vector_private *vp = netdev_priv(netdev);
ring->rx_max_pending = vp->rx_queue->max_depth;
ring->tx_max_pending = vp->tx_queue->max_depth;
ring->rx_pending = vp->rx_queue->max_depth;
ring->tx_pending = vp->tx_queue->max_depth;
}
static void vector_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
{
switch (stringset) {
case ETH_SS_TEST:
*buf = '\0';
break;
case ETH_SS_STATS:
memcpy(buf, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
break;
default:
WARN_ON(1);
break;
}
}
static int vector_get_sset_count(struct net_device *dev, int sset)
{
switch (sset) {
case ETH_SS_TEST:
return 0;
case ETH_SS_STATS:
return VECTOR_NUM_STATS;
default:
return -EOPNOTSUPP;
}
}
static void vector_get_ethtool_stats(struct net_device *dev,
struct ethtool_stats *estats,
u64 *tmp_stats)
{
struct vector_private *vp = netdev_priv(dev);
memcpy(tmp_stats, &vp->estats, sizeof(struct vector_estats));
}
static int vector_get_coalesce(struct net_device *netdev,
struct ethtool_coalesce *ec)
{
struct vector_private *vp = netdev_priv(netdev);
ec->tx_coalesce_usecs = (vp->coalesce * 1000000) / HZ;
return 0;
}
static int vector_set_coalesce(struct net_device *netdev,
struct ethtool_coalesce *ec)
{
struct vector_private *vp = netdev_priv(netdev);
vp->coalesce = (ec->tx_coalesce_usecs * HZ) / 1000000;
if (vp->coalesce == 0)
vp->coalesce = 1;
return 0;
}
static const struct ethtool_ops vector_net_ethtool_ops = {
.get_drvinfo = vector_net_get_drvinfo,
.get_link = ethtool_op_get_link,
.get_ts_info = ethtool_op_get_ts_info,
.get_ringparam = vector_get_ringparam,
.get_strings = vector_get_strings,
.get_sset_count = vector_get_sset_count,
.get_ethtool_stats = vector_get_ethtool_stats,
.get_coalesce = vector_get_coalesce,
.set_coalesce = vector_set_coalesce,
};
static const struct net_device_ops vector_netdev_ops = {
.ndo_open = vector_net_open,
.ndo_stop = vector_net_close,
.ndo_start_xmit = vector_net_start_xmit,
.ndo_set_rx_mode = vector_net_set_multicast_list,
.ndo_tx_timeout = vector_net_tx_timeout,
.ndo_set_mac_address = eth_mac_addr,
.ndo_validate_addr = eth_validate_addr,
.ndo_fix_features = vector_fix_features,
.ndo_set_features = vector_set_features,
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = vector_net_poll_controller,
#endif
};
static void vector_timer_expire(struct timer_list *t)
{
struct vector_private *vp = from_timer(vp, t, tl);
vp->estats.tx_kicks++;
vector_send(vp->tx_queue);
}
static void vector_eth_configure(
int n,
struct arglist *def
)
{
struct vector_device *device;
struct net_device *dev;
struct vector_private *vp;
int err;
device = kzalloc(sizeof(*device), GFP_KERNEL);
if (device == NULL) {
printk(KERN_ERR "eth_configure failed to allocate struct "
"vector_device\n");
return;
}
dev = alloc_etherdev(sizeof(struct vector_private));
if (dev == NULL) {
printk(KERN_ERR "eth_configure: failed to allocate struct "
"net_device for vec%d\n", n);
goto out_free_device;
}
dev->mtu = get_mtu(def);
INIT_LIST_HEAD(&device->list);
device->unit = n;
/* If this name ends up conflicting with an existing registered
* netdevice, that is OK, register_netdev{,ice}() will notice this
* and fail.
*/
snprintf(dev->name, sizeof(dev->name), "vec%d", n);
uml_net_setup_etheraddr(dev, uml_vector_fetch_arg(def, "mac"));
vp = netdev_priv(dev);
/* sysfs register */
if (!driver_registered) {
platform_driver_register(&uml_net_driver);
driver_registered = 1;
}
device->pdev.id = n;
device->pdev.name = DRIVER_NAME;
device->pdev.dev.release = vector_device_release;
dev_set_drvdata(&device->pdev.dev, device);
if (platform_device_register(&device->pdev))
goto out_free_netdev;
SET_NETDEV_DEV(dev, &device->pdev.dev);
device->dev = dev;
*vp = ((struct vector_private)
{
.list = LIST_HEAD_INIT(vp->list),
.dev = dev,
.unit = n,
.options = get_transport_options(def),
.rx_irq = 0,
.tx_irq = 0,
.parsed = def,
.max_packet = get_mtu(def) + ETH_HEADER_OTHER,
/* TODO - we need to calculate headroom so that ip header
* is 16 byte aligned all the time
*/
.headroom = get_headroom(def),
.form_header = NULL,
.verify_header = NULL,
.header_rxbuffer = NULL,
.header_txbuffer = NULL,
.header_size = 0,
.rx_header_size = 0,
.rexmit_scheduled = false,
.opened = false,
.transport_data = NULL,
.in_write_poll = false,
.coalesce = 2,
.req_size = get_req_size(def)
});
dev->features = dev->hw_features = (NETIF_F_SG | NETIF_F_FRAGLIST);
tasklet_init(&vp->tx_poll, vector_tx_poll, (unsigned long)vp);
INIT_WORK(&vp->reset_tx, vector_reset_tx);
timer_setup(&vp->tl, vector_timer_expire, 0);
spin_lock_init(&vp->lock);
/* FIXME */
dev->netdev_ops = &vector_netdev_ops;
dev->ethtool_ops = &vector_net_ethtool_ops;
dev->watchdog_timeo = (HZ >> 1);
/* primary IRQ - fixme */
dev->irq = 0; /* we will adjust this once opened */
rtnl_lock();
err = register_netdevice(dev);
rtnl_unlock();
if (err)
goto out_undo_user_init;
spin_lock(&vector_devices_lock);
list_add(&device->list, &vector_devices);
spin_unlock(&vector_devices_lock);
return;
out_undo_user_init:
return;
out_free_netdev:
free_netdev(dev);
out_free_device:
kfree(device);
}
/*
* Invoked late in the init
*/
static int __init vector_init(void)
{
struct list_head *ele;
struct vector_cmd_line_arg *def;
struct arglist *parsed;
list_for_each(ele, &vec_cmd_line) {
def = list_entry(ele, struct vector_cmd_line_arg, list);
parsed = uml_parse_vector_ifspec(def->arguments);
if (parsed != NULL)
vector_eth_configure(def->unit, parsed);
}
return 0;
}
/* Invoked at initial argument parsing, only stores
* arguments until a proper vector_init is called
* later
*/
static int __init vector_setup(char *str)
{
char *error;
int n, err;
struct vector_cmd_line_arg *new;
err = vector_parse(str, &n, &str, &error);
if (err) {
printk(KERN_ERR "vector_setup - Couldn't parse '%s' : %s\n",
str, error);
return 1;
}
new = memblock_alloc(sizeof(*new), 0);
INIT_LIST_HEAD(&new->list);
new->unit = n;
new->arguments = str;
list_add_tail(&new->list, &vec_cmd_line);
return 1;
}
__setup("vec", vector_setup);
__uml_help(vector_setup,
"vec[0-9]+:<option>=<value>,<option>=<value>\n"
" Configure a vector io network device.\n\n"
);
late_initcall(vector_init);
static struct mc_device vector_mc = {
.list = LIST_HEAD_INIT(vector_mc.list),
.name = "vec",
.config = vector_config,
.get_config = NULL,
.id = vector_id,
.remove = vector_remove,
};
#ifdef CONFIG_INET
static int vector_inetaddr_event(
struct notifier_block *this,
unsigned long event,
void *ptr)
{
return NOTIFY_DONE;
}
static struct notifier_block vector_inetaddr_notifier = {
.notifier_call = vector_inetaddr_event,
};
static void inet_register(void)
{
register_inetaddr_notifier(&vector_inetaddr_notifier);
}
#else
static inline void inet_register(void)
{
}
#endif
static int vector_net_init(void)
{
mconsole_register_dev(&vector_mc);
inet_register();
return 0;
}
__initcall(vector_net_init);
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