Files
grub/grub-core/net/drivers/ieee1275/ofnet.c
T
Michael Chang d35ff22516 net/drivers/ieee1275/ofnet: Remove 200 ms timeout in get_card_packet() to reduce input latency
When GRUB image is netbooted on ppc64le, the keyboard input exhibits
significant latency, reports even say that characters are processed
about once per second. This issue makes interactively trying to debug
a ppc64le config very difficult.

It seems that the latency is largely caused by a 200 ms timeout in the
idle event loop, during which the network card interface is consistently
polled for incoming packets. Often, no packets arrive during this
period, so the timeout nearly always expires, which blocks the response
to key inputs.

Furthermore, this 200 ms timeout might not need to be enforced at this
basic layer, considering that GRUB performs synchronous reads and its
timeout management is actually handled by higher layers, not directly in
the card instance. Additionally, the idle polling, which reacts to
unsolicited packets like ICMP and SLAAC, would be fine at a less frequent
polling interval, rather than needing a timeout for receiving a response.

For these reasons, we believe the timeout in get_card_packet() should be
effectively removed. According to test results, the delay has disappeared,
and it is now much easier to use interactively.

Signed-Off-by: Michael Chang <mchang@suse.com>
Tested-by: Tony Jones <tonyj@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2024-06-20 14:44:10 +02:00

549 lines
14 KiB
C

/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010,2011 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/net/netbuff.h>
#include <grub/ieee1275/ieee1275.h>
#include <grub/dl.h>
#include <grub/net.h>
#include <grub/time.h>
#include <grub/i18n.h>
GRUB_MOD_LICENSE ("GPLv3+");
struct grub_ofnetcard_data
{
char *path;
char *suffix;
grub_ieee1275_ihandle_t handle;
};
static grub_err_t
card_open (struct grub_net_card *dev)
{
int status;
struct grub_ofnetcard_data *data = dev->data;
status = grub_ieee1275_open (data->path, &(data->handle));
if (status)
return grub_error (GRUB_ERR_IO, "Couldn't open network card.");
return GRUB_ERR_NONE;
}
static void
card_close (struct grub_net_card *dev)
{
struct grub_ofnetcard_data *data = dev->data;
if (data->handle)
grub_ieee1275_close (data->handle);
}
static grub_err_t
send_card_buffer (struct grub_net_card *dev, struct grub_net_buff *pack)
{
grub_ssize_t actual;
int status;
struct grub_ofnetcard_data *data = dev->data;
grub_size_t len;
len = (pack->tail - pack->data);
if (len > dev->mtu)
len = dev->mtu;
grub_memcpy (dev->txbuf, pack->data, len);
status = grub_ieee1275_write (data->handle, dev->txbuf,
len, &actual);
if (status)
return grub_error (GRUB_ERR_IO, N_("couldn't send network packet"));
return GRUB_ERR_NONE;
}
static struct grub_net_buff *
get_card_packet (struct grub_net_card *dev)
{
grub_ssize_t actual;
int rc;
struct grub_ofnetcard_data *data = dev->data;
struct grub_net_buff *nb;
rc = grub_ieee1275_read (data->handle, dev->rcvbuf, dev->rcvbufsize, &actual);
if (actual <= 0 || rc < 0)
return NULL;
nb = grub_netbuff_alloc (actual + 2);
if (!nb)
return NULL;
/* Reserve 2 bytes so that 2 + 14/18 bytes of ethernet header is divisible
by 4. So that IP header is aligned on 4 bytes. */
grub_netbuff_reserve (nb, 2);
grub_memcpy (nb->data, dev->rcvbuf, actual);
if (grub_netbuff_put (nb, actual))
{
grub_netbuff_free (nb);
return NULL;
}
return nb;
}
static struct grub_net_card_driver ofdriver =
{
.name = "ofnet",
.open = card_open,
.close = card_close,
.send = send_card_buffer,
.recv = get_card_packet
};
static const struct
{
const char *name;
int offset;
}
bootp_response_properties[] =
{
{ .name = "bootp-response", .offset = 0},
{ .name = "dhcp-response", .offset = 0},
{ .name = "bootpreply-packet", .offset = 0x2a},
};
enum
{
BOOTARGS_SERVER_ADDR,
BOOTARGS_FILENAME,
BOOTARGS_CLIENT_ADDR,
BOOTARGS_GATEWAY_ADDR,
BOOTARGS_BOOTP_RETRIES,
BOOTARGS_TFTP_RETRIES,
BOOTARGS_SUBNET_MASK,
BOOTARGS_BLOCKSIZE
};
static int
grub_ieee1275_parse_bootpath (const char *devpath, char *bootpath,
char **device, struct grub_net_card **card)
{
char *args;
char *comma_char = 0;
char *equal_char = 0;
grub_size_t field_counter = 0;
grub_net_network_level_address_t client_addr = {0, {0}, 0}, gateway_addr = {0, {0}, 0}, subnet_mask = {0, {0}, 0};
grub_net_link_level_address_t hw_addr = {0, {{0, 0, 0, 0, 0, 0}}};
grub_net_interface_flags_t flags = 0;
struct grub_net_network_level_interface *inter = NULL;
grub_uint16_t vlantag = 0;
hw_addr.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
args = bootpath + grub_strlen (devpath) + 1;
do
{
comma_char = grub_strchr (args, ',');
if (comma_char != 0)
*comma_char = 0;
/* Check if it's an option (like speed=auto) and not a default parameter */
equal_char = grub_strchr (args, '=');
if (equal_char != 0)
{
*equal_char = 0;
grub_env_set_net_property ((*card)->name, args, equal_char + 1,
grub_strlen(equal_char + 1));
if ((grub_strcmp (args, "vtag") == 0) &&
(grub_strlen (equal_char + 1) == 8))
vlantag = grub_strtoul (equal_char + 1 + 4, 0, 16);
*equal_char = '=';
}
else
{
switch (field_counter++)
{
case BOOTARGS_SERVER_ADDR:
*device = grub_xasprintf ("tftp,%s", args);
if (!*device)
return grub_errno;
break;
case BOOTARGS_CLIENT_ADDR:
grub_net_resolve_address (args, &client_addr);
break;
case BOOTARGS_GATEWAY_ADDR:
grub_net_resolve_address (args, &gateway_addr);
break;
case BOOTARGS_SUBNET_MASK:
grub_net_resolve_address (args, &subnet_mask);
break;
}
}
args = comma_char + 1;
if (comma_char != 0)
*comma_char = ',';
} while (comma_char != 0);
if ((client_addr.ipv4 != 0) && (subnet_mask.ipv4 != 0))
{
grub_ieee1275_phandle_t devhandle;
grub_ieee1275_finddevice (devpath, &devhandle);
grub_ieee1275_get_property (devhandle, "mac-address",
hw_addr.mac, sizeof(hw_addr.mac), 0);
inter = grub_net_add_addr ((*card)->name, *card, &client_addr, &hw_addr,
flags);
inter->vlantag = vlantag;
grub_net_add_ipv4_local (inter,
__builtin_clz (~grub_be_to_cpu32 (subnet_mask.ipv4)));
}
if (gateway_addr.ipv4 != 0)
{
grub_net_network_level_netaddress_t target;
char *rname;
target.type = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4;
target.ipv4.base = 0;
target.ipv4.masksize = 0;
rname = grub_xasprintf ("%s:default", ((*card)->name));
if (rname)
grub_net_add_route_gw (rname, target, gateway_addr, inter);
else
return grub_errno;
}
return 0;
}
static void
grub_ieee1275_net_config_real (const char *devpath, char **device, char **path,
char *bootpath)
{
struct grub_net_card *card;
/* FIXME: Check that it's the right card. */
FOR_NET_CARDS (card)
{
char *bootp_response;
char *canon;
char c;
struct grub_ofnetcard_data *data;
grub_ssize_t size = -1;
unsigned int i;
if (card->driver != &ofdriver)
continue;
data = card->data;
c = *data->suffix;
*data->suffix = '\0';
canon = grub_ieee1275_canonicalise_devname (data->path);
*data->suffix = c;
if (grub_strcmp (devpath, canon) != 0)
{
grub_free (canon);
continue;
}
grub_free (canon);
grub_ieee1275_parse_bootpath (devpath, bootpath, device, &card);
for (i = 0; i < ARRAY_SIZE (bootp_response_properties); i++)
if (grub_ieee1275_get_property_length (grub_ieee1275_chosen,
bootp_response_properties[i].name,
&size) >= 0)
break;
if (size < 0)
return;
bootp_response = grub_malloc (size);
if (!bootp_response)
{
grub_print_error ();
return;
}
if (grub_ieee1275_get_property (grub_ieee1275_chosen,
bootp_response_properties[i].name,
bootp_response, size, 0) < 0)
return;
grub_net_configure_by_dhcp_ack (card->name, card, 0,
(struct grub_net_bootp_packet *)
(bootp_response
+ bootp_response_properties[i].offset),
size - bootp_response_properties[i].offset,
1, device, path);
grub_free (bootp_response);
return;
}
}
/* Allocate memory with alloc-mem */
static void *
grub_ieee1275_alloc_mem (grub_size_t len)
{
struct alloc_args
{
struct grub_ieee1275_common_hdr common;
grub_ieee1275_cell_t method;
grub_ieee1275_cell_t len;
grub_ieee1275_cell_t catch;
grub_ieee1275_cell_t result;
}
args;
INIT_IEEE1275_COMMON (&args.common, "interpret", 2, 2);
args.len = len;
args.method = (grub_ieee1275_cell_t) "alloc-mem";
if (IEEE1275_CALL_ENTRY_FN (&args) == -1 || args.catch)
{
grub_error (GRUB_ERR_INVALID_COMMAND, N_("alloc-mem failed"));
return NULL;
}
else
return (void *)args.result;
}
/* Free memory allocated by alloc-mem */
static grub_err_t
grub_ieee1275_free_mem (void *addr, grub_size_t len)
{
struct free_args
{
struct grub_ieee1275_common_hdr common;
grub_ieee1275_cell_t method;
grub_ieee1275_cell_t len;
grub_ieee1275_cell_t addr;
grub_ieee1275_cell_t catch;
}
args;
INIT_IEEE1275_COMMON (&args.common, "interpret", 3, 1);
args.addr = (grub_ieee1275_cell_t)addr;
args.len = len;
args.method = (grub_ieee1275_cell_t) "free-mem";
if (IEEE1275_CALL_ENTRY_FN(&args) == -1 || args.catch)
{
grub_error (GRUB_ERR_INVALID_COMMAND, N_("free-mem failed"));
return grub_errno;
}
return GRUB_ERR_NONE;
}
static void *
ofnet_alloc_netbuf (grub_size_t len)
{
if (grub_ieee1275_test_flag (GRUB_IEEE1275_FLAG_VIRT_TO_REAL_BROKEN))
return grub_ieee1275_alloc_mem (len);
else
return grub_zalloc (len);
}
static void
ofnet_free_netbuf (void *addr, grub_size_t len)
{
if (grub_ieee1275_test_flag (GRUB_IEEE1275_FLAG_VIRT_TO_REAL_BROKEN))
grub_ieee1275_free_mem (addr, len);
else
grub_free (addr);
}
static int
search_net_devices (struct grub_ieee1275_devalias *alias)
{
struct grub_ofnetcard_data *ofdata;
struct grub_net_card *card;
grub_ieee1275_phandle_t devhandle;
grub_net_link_level_address_t lla;
grub_ssize_t prop_size;
grub_uint64_t prop;
grub_uint8_t *pprop;
char *shortname;
char need_suffix = 1;
if (grub_strcmp (alias->type, "network") != 0)
return 0;
ofdata = grub_malloc (sizeof (struct grub_ofnetcard_data));
if (!ofdata)
{
grub_print_error ();
return 1;
}
card = grub_zalloc (sizeof (struct grub_net_card));
if (!card)
{
grub_free (ofdata);
grub_print_error ();
return 1;
}
#define SUFFIX ":speed=auto,duplex=auto,1.1.1.1,dummy,1.1.1.1,1.1.1.1,5,5,1.1.1.1,512"
if (grub_ieee1275_test_flag (GRUB_IEEE1275_FLAG_NO_OFNET_SUFFIX))
need_suffix = 0;
/* sun4v vnet devices do not support setting duplex/speed */
{
char *ptr;
grub_ieee1275_finddevice (alias->path, &devhandle);
grub_ieee1275_get_property_length (devhandle, "compatible", &prop_size);
if (prop_size > 0)
{
pprop = grub_malloc (prop_size);
if (!pprop)
{
grub_free (card);
grub_free (ofdata);
grub_print_error ();
return 1;
}
if (!grub_ieee1275_get_property (devhandle, "compatible",
pprop, prop_size, NULL))
{
for (ptr = (char *) pprop; ptr - (char *) pprop < prop_size;
ptr += grub_strlen (ptr) + 1)
{
if (!grub_strcmp(ptr, "SUNW,sun4v-network"))
need_suffix = 0;
}
}
grub_free (pprop);
}
}
if (need_suffix)
ofdata->path = grub_malloc (grub_strlen (alias->path) + sizeof (SUFFIX));
else
ofdata->path = grub_malloc (grub_strlen (alias->path) + 1);
if (!ofdata->path)
{
grub_print_error ();
return 0;
}
ofdata->suffix = grub_stpcpy (ofdata->path, alias->path);
if (need_suffix)
grub_memcpy (ofdata->suffix, SUFFIX, sizeof (SUFFIX));
else
*ofdata->suffix = '\0';
grub_ieee1275_finddevice (ofdata->path, &devhandle);
{
grub_uint32_t t;
if (grub_ieee1275_get_integer_property (devhandle,
"max-frame-size", &t,
sizeof (t), 0))
card->mtu = 1500;
else
card->mtu = t;
}
pprop = (grub_uint8_t *) &prop;
if (grub_ieee1275_get_property (devhandle, "mac-address",
pprop, sizeof(prop), &prop_size)
&& grub_ieee1275_get_property (devhandle, "local-mac-address",
pprop, sizeof(prop), &prop_size))
{
grub_error (GRUB_ERR_IO, "Couldn't retrieve mac address.");
grub_print_error ();
return 0;
}
if (prop_size == 8)
grub_memcpy (&lla.mac, pprop+2, 6);
else
grub_memcpy (&lla.mac, pprop, 6);
lla.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
card->default_address = lla;
card->txbufsize = ALIGN_UP (card->mtu, 64) + 256;
card->rcvbufsize = ALIGN_UP (card->mtu, 64) + 256;
card->txbuf = ofnet_alloc_netbuf (card->txbufsize);
if (!card->txbuf)
goto fail_netbuf;
card->rcvbuf = ofnet_alloc_netbuf (card->rcvbufsize);
if (!card->rcvbuf)
{
grub_error_push ();
ofnet_free_netbuf (card->txbuf, card->txbufsize);
grub_error_pop ();
goto fail_netbuf;
}
card->driver = NULL;
card->data = ofdata;
card->flags = 0;
shortname = grub_ieee1275_get_devname (alias->path);
card->name = grub_xasprintf ("ofnet_%s", shortname ? : alias->path);
card->idle_poll_delay_ms = 10;
grub_free (shortname);
card->driver = &ofdriver;
grub_net_card_register (card);
return 0;
fail_netbuf:
grub_free (ofdata->path);
grub_free (ofdata);
grub_free (card);
grub_print_error ();
return 0;
}
static void
grub_ofnet_findcards (void)
{
/* Look at all nodes for devices of the type network. */
grub_ieee1275_devices_iterate (search_net_devices);
}
GRUB_MOD_INIT(ofnet)
{
grub_ofnet_findcards ();
grub_ieee1275_net_config = grub_ieee1275_net_config_real;
}
GRUB_MOD_FINI(ofnet)
{
struct grub_net_card *card, *next;
FOR_NET_CARDS_SAFE (card, next)
if (card->driver && grub_strcmp (card->driver->name, "ofnet") == 0)
grub_net_card_unregister (card);
grub_ieee1275_net_config = 0;
}