mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Fabian Frederick](/assets/img/avatar_default.png)
Use current logging functions and add module name prefix. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: David S. Miller <davem@davemloft.net>
407 lines
12 KiB
C
407 lines
12 KiB
C
/*
|
|
* Linux WiMAX
|
|
* Generic messaging interface between userspace and driver/device
|
|
*
|
|
*
|
|
* Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com>
|
|
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License version
|
|
* 2 as published by the Free Software Foundation.
|
|
*
|
|
* This program 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 this program; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
* 02110-1301, USA.
|
|
*
|
|
*
|
|
* This implements a direct communication channel between user space and
|
|
* the driver/device, by which free form messages can be sent back and
|
|
* forth.
|
|
*
|
|
* This is intended for device-specific features, vendor quirks, etc.
|
|
*
|
|
* See include/net/wimax.h
|
|
*
|
|
* GENERIC NETLINK ENCODING AND CAPACITY
|
|
*
|
|
* A destination "pipe name" is added to each message; it is up to the
|
|
* drivers to assign or use those names (if using them at all).
|
|
*
|
|
* Messages are encoded as a binary netlink attribute using nla_put()
|
|
* using type NLA_UNSPEC (as some versions of libnl still in
|
|
* deployment don't yet understand NLA_BINARY).
|
|
*
|
|
* The maximum capacity of this transport is PAGESIZE per message (so
|
|
* the actual payload will be bit smaller depending on the
|
|
* netlink/generic netlink attributes and headers).
|
|
*
|
|
* RECEPTION OF MESSAGES
|
|
*
|
|
* When a message is received from user space, it is passed verbatim
|
|
* to the driver calling wimax_dev->op_msg_from_user(). The return
|
|
* value from this function is passed back to user space as an ack
|
|
* over the generic netlink protocol.
|
|
*
|
|
* The stack doesn't do any processing or interpretation of these
|
|
* messages.
|
|
*
|
|
* SENDING MESSAGES
|
|
*
|
|
* Messages can be sent with wimax_msg().
|
|
*
|
|
* If the message delivery needs to happen on a different context to
|
|
* that of its creation, wimax_msg_alloc() can be used to get a
|
|
* pointer to the message that can be delivered later on with
|
|
* wimax_msg_send().
|
|
*
|
|
* ROADMAP
|
|
*
|
|
* wimax_gnl_doit_msg_from_user() Process a message from user space
|
|
* wimax_dev_get_by_genl_info()
|
|
* wimax_dev->op_msg_from_user() Delivery of message to the driver
|
|
*
|
|
* wimax_msg() Send a message to user space
|
|
* wimax_msg_alloc()
|
|
* wimax_msg_send()
|
|
*/
|
|
#include <linux/device.h>
|
|
#include <linux/slab.h>
|
|
#include <net/genetlink.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/wimax.h>
|
|
#include <linux/security.h>
|
|
#include <linux/export.h>
|
|
#include "wimax-internal.h"
|
|
|
|
|
|
#define D_SUBMODULE op_msg
|
|
#include "debug-levels.h"
|
|
|
|
|
|
/**
|
|
* wimax_msg_alloc - Create a new skb for sending a message to userspace
|
|
*
|
|
* @wimax_dev: WiMAX device descriptor
|
|
* @pipe_name: "named pipe" the message will be sent to
|
|
* @msg: pointer to the message data to send
|
|
* @size: size of the message to send (in bytes), including the header.
|
|
* @gfp_flags: flags for memory allocation.
|
|
*
|
|
* Returns: %0 if ok, negative errno code on error
|
|
*
|
|
* Description:
|
|
*
|
|
* Allocates an skb that will contain the message to send to user
|
|
* space over the messaging pipe and initializes it, copying the
|
|
* payload.
|
|
*
|
|
* Once this call is done, you can deliver it with
|
|
* wimax_msg_send().
|
|
*
|
|
* IMPORTANT:
|
|
*
|
|
* Don't use skb_push()/skb_pull()/skb_reserve() on the skb, as
|
|
* wimax_msg_send() depends on skb->data being placed at the
|
|
* beginning of the user message.
|
|
*
|
|
* Unlike other WiMAX stack calls, this call can be used way early,
|
|
* even before wimax_dev_add() is called, as long as the
|
|
* wimax_dev->net_dev pointer is set to point to a proper
|
|
* net_dev. This is so that drivers can use it early in case they need
|
|
* to send stuff around or communicate with user space.
|
|
*/
|
|
struct sk_buff *wimax_msg_alloc(struct wimax_dev *wimax_dev,
|
|
const char *pipe_name,
|
|
const void *msg, size_t size,
|
|
gfp_t gfp_flags)
|
|
{
|
|
int result;
|
|
struct device *dev = wimax_dev_to_dev(wimax_dev);
|
|
size_t msg_size;
|
|
void *genl_msg;
|
|
struct sk_buff *skb;
|
|
|
|
msg_size = nla_total_size(size)
|
|
+ nla_total_size(sizeof(u32))
|
|
+ (pipe_name ? nla_total_size(strlen(pipe_name)) : 0);
|
|
result = -ENOMEM;
|
|
skb = genlmsg_new(msg_size, gfp_flags);
|
|
if (skb == NULL)
|
|
goto error_new;
|
|
genl_msg = genlmsg_put(skb, 0, 0, &wimax_gnl_family,
|
|
0, WIMAX_GNL_OP_MSG_TO_USER);
|
|
if (genl_msg == NULL) {
|
|
dev_err(dev, "no memory to create generic netlink message\n");
|
|
goto error_genlmsg_put;
|
|
}
|
|
result = nla_put_u32(skb, WIMAX_GNL_MSG_IFIDX,
|
|
wimax_dev->net_dev->ifindex);
|
|
if (result < 0) {
|
|
dev_err(dev, "no memory to add ifindex attribute\n");
|
|
goto error_nla_put;
|
|
}
|
|
if (pipe_name) {
|
|
result = nla_put_string(skb, WIMAX_GNL_MSG_PIPE_NAME,
|
|
pipe_name);
|
|
if (result < 0) {
|
|
dev_err(dev, "no memory to add pipe_name attribute\n");
|
|
goto error_nla_put;
|
|
}
|
|
}
|
|
result = nla_put(skb, WIMAX_GNL_MSG_DATA, size, msg);
|
|
if (result < 0) {
|
|
dev_err(dev, "no memory to add payload (msg %p size %zu) in "
|
|
"attribute: %d\n", msg, size, result);
|
|
goto error_nla_put;
|
|
}
|
|
genlmsg_end(skb, genl_msg);
|
|
return skb;
|
|
|
|
error_nla_put:
|
|
error_genlmsg_put:
|
|
error_new:
|
|
nlmsg_free(skb);
|
|
return ERR_PTR(result);
|
|
}
|
|
EXPORT_SYMBOL_GPL(wimax_msg_alloc);
|
|
|
|
|
|
/**
|
|
* wimax_msg_data_len - Return a pointer and size of a message's payload
|
|
*
|
|
* @msg: Pointer to a message created with wimax_msg_alloc()
|
|
* @size: Pointer to where to store the message's size
|
|
*
|
|
* Returns the pointer to the message data.
|
|
*/
|
|
const void *wimax_msg_data_len(struct sk_buff *msg, size_t *size)
|
|
{
|
|
struct nlmsghdr *nlh = (void *) msg->head;
|
|
struct nlattr *nla;
|
|
|
|
nla = nlmsg_find_attr(nlh, sizeof(struct genlmsghdr),
|
|
WIMAX_GNL_MSG_DATA);
|
|
if (nla == NULL) {
|
|
pr_err("Cannot find attribute WIMAX_GNL_MSG_DATA\n");
|
|
return NULL;
|
|
}
|
|
*size = nla_len(nla);
|
|
return nla_data(nla);
|
|
}
|
|
EXPORT_SYMBOL_GPL(wimax_msg_data_len);
|
|
|
|
|
|
/**
|
|
* wimax_msg_data - Return a pointer to a message's payload
|
|
*
|
|
* @msg: Pointer to a message created with wimax_msg_alloc()
|
|
*/
|
|
const void *wimax_msg_data(struct sk_buff *msg)
|
|
{
|
|
struct nlmsghdr *nlh = (void *) msg->head;
|
|
struct nlattr *nla;
|
|
|
|
nla = nlmsg_find_attr(nlh, sizeof(struct genlmsghdr),
|
|
WIMAX_GNL_MSG_DATA);
|
|
if (nla == NULL) {
|
|
pr_err("Cannot find attribute WIMAX_GNL_MSG_DATA\n");
|
|
return NULL;
|
|
}
|
|
return nla_data(nla);
|
|
}
|
|
EXPORT_SYMBOL_GPL(wimax_msg_data);
|
|
|
|
|
|
/**
|
|
* wimax_msg_len - Return a message's payload length
|
|
*
|
|
* @msg: Pointer to a message created with wimax_msg_alloc()
|
|
*/
|
|
ssize_t wimax_msg_len(struct sk_buff *msg)
|
|
{
|
|
struct nlmsghdr *nlh = (void *) msg->head;
|
|
struct nlattr *nla;
|
|
|
|
nla = nlmsg_find_attr(nlh, sizeof(struct genlmsghdr),
|
|
WIMAX_GNL_MSG_DATA);
|
|
if (nla == NULL) {
|
|
pr_err("Cannot find attribute WIMAX_GNL_MSG_DATA\n");
|
|
return -EINVAL;
|
|
}
|
|
return nla_len(nla);
|
|
}
|
|
EXPORT_SYMBOL_GPL(wimax_msg_len);
|
|
|
|
|
|
/**
|
|
* wimax_msg_send - Send a pre-allocated message to user space
|
|
*
|
|
* @wimax_dev: WiMAX device descriptor
|
|
*
|
|
* @skb: &struct sk_buff returned by wimax_msg_alloc(). Note the
|
|
* ownership of @skb is transferred to this function.
|
|
*
|
|
* Returns: 0 if ok, < 0 errno code on error
|
|
*
|
|
* Description:
|
|
*
|
|
* Sends a free-form message that was preallocated with
|
|
* wimax_msg_alloc() and filled up.
|
|
*
|
|
* Assumes that once you pass an skb to this function for sending, it
|
|
* owns it and will release it when done (on success).
|
|
*
|
|
* IMPORTANT:
|
|
*
|
|
* Don't use skb_push()/skb_pull()/skb_reserve() on the skb, as
|
|
* wimax_msg_send() depends on skb->data being placed at the
|
|
* beginning of the user message.
|
|
*
|
|
* Unlike other WiMAX stack calls, this call can be used way early,
|
|
* even before wimax_dev_add() is called, as long as the
|
|
* wimax_dev->net_dev pointer is set to point to a proper
|
|
* net_dev. This is so that drivers can use it early in case they need
|
|
* to send stuff around or communicate with user space.
|
|
*/
|
|
int wimax_msg_send(struct wimax_dev *wimax_dev, struct sk_buff *skb)
|
|
{
|
|
struct device *dev = wimax_dev_to_dev(wimax_dev);
|
|
void *msg = skb->data;
|
|
size_t size = skb->len;
|
|
might_sleep();
|
|
|
|
d_printf(1, dev, "CTX: wimax msg, %zu bytes\n", size);
|
|
d_dump(2, dev, msg, size);
|
|
genlmsg_multicast(&wimax_gnl_family, skb, 0, 0, GFP_KERNEL);
|
|
d_printf(1, dev, "CTX: genl multicast done\n");
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(wimax_msg_send);
|
|
|
|
|
|
/**
|
|
* wimax_msg - Send a message to user space
|
|
*
|
|
* @wimax_dev: WiMAX device descriptor (properly referenced)
|
|
* @pipe_name: "named pipe" the message will be sent to
|
|
* @buf: pointer to the message to send.
|
|
* @size: size of the buffer pointed to by @buf (in bytes).
|
|
* @gfp_flags: flags for memory allocation.
|
|
*
|
|
* Returns: %0 if ok, negative errno code on error.
|
|
*
|
|
* Description:
|
|
*
|
|
* Sends a free-form message to user space on the device @wimax_dev.
|
|
*
|
|
* NOTES:
|
|
*
|
|
* Once the @skb is given to this function, who will own it and will
|
|
* release it when done (unless it returns error).
|
|
*/
|
|
int wimax_msg(struct wimax_dev *wimax_dev, const char *pipe_name,
|
|
const void *buf, size_t size, gfp_t gfp_flags)
|
|
{
|
|
int result = -ENOMEM;
|
|
struct sk_buff *skb;
|
|
|
|
skb = wimax_msg_alloc(wimax_dev, pipe_name, buf, size, gfp_flags);
|
|
if (IS_ERR(skb))
|
|
result = PTR_ERR(skb);
|
|
else
|
|
result = wimax_msg_send(wimax_dev, skb);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL_GPL(wimax_msg);
|
|
|
|
/*
|
|
* Relays a message from user space to the driver
|
|
*
|
|
* The skb is passed to the driver-specific function with the netlink
|
|
* and generic netlink headers already stripped.
|
|
*
|
|
* This call will block while handling/relaying the message.
|
|
*/
|
|
int wimax_gnl_doit_msg_from_user(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
int result, ifindex;
|
|
struct wimax_dev *wimax_dev;
|
|
struct device *dev;
|
|
struct nlmsghdr *nlh = info->nlhdr;
|
|
char *pipe_name;
|
|
void *msg_buf;
|
|
size_t msg_len;
|
|
|
|
might_sleep();
|
|
d_fnstart(3, NULL, "(skb %p info %p)\n", skb, info);
|
|
result = -ENODEV;
|
|
if (info->attrs[WIMAX_GNL_MSG_IFIDX] == NULL) {
|
|
pr_err("WIMAX_GNL_MSG_FROM_USER: can't find IFIDX attribute\n");
|
|
goto error_no_wimax_dev;
|
|
}
|
|
ifindex = nla_get_u32(info->attrs[WIMAX_GNL_MSG_IFIDX]);
|
|
wimax_dev = wimax_dev_get_by_genl_info(info, ifindex);
|
|
if (wimax_dev == NULL)
|
|
goto error_no_wimax_dev;
|
|
dev = wimax_dev_to_dev(wimax_dev);
|
|
|
|
/* Unpack arguments */
|
|
result = -EINVAL;
|
|
if (info->attrs[WIMAX_GNL_MSG_DATA] == NULL) {
|
|
dev_err(dev, "WIMAX_GNL_MSG_FROM_USER: can't find MSG_DATA "
|
|
"attribute\n");
|
|
goto error_no_data;
|
|
}
|
|
msg_buf = nla_data(info->attrs[WIMAX_GNL_MSG_DATA]);
|
|
msg_len = nla_len(info->attrs[WIMAX_GNL_MSG_DATA]);
|
|
|
|
if (info->attrs[WIMAX_GNL_MSG_PIPE_NAME] == NULL)
|
|
pipe_name = NULL;
|
|
else {
|
|
struct nlattr *attr = info->attrs[WIMAX_GNL_MSG_PIPE_NAME];
|
|
size_t attr_len = nla_len(attr);
|
|
/* libnl-1.1 does not yet support NLA_NUL_STRING */
|
|
result = -ENOMEM;
|
|
pipe_name = kstrndup(nla_data(attr), attr_len + 1, GFP_KERNEL);
|
|
if (pipe_name == NULL)
|
|
goto error_alloc;
|
|
pipe_name[attr_len] = 0;
|
|
}
|
|
mutex_lock(&wimax_dev->mutex);
|
|
result = wimax_dev_is_ready(wimax_dev);
|
|
if (result == -ENOMEDIUM)
|
|
result = 0;
|
|
if (result < 0)
|
|
goto error_not_ready;
|
|
result = -ENOSYS;
|
|
if (wimax_dev->op_msg_from_user == NULL)
|
|
goto error_noop;
|
|
|
|
d_printf(1, dev,
|
|
"CRX: nlmsghdr len %u type %u flags 0x%04x seq 0x%x pid %u\n",
|
|
nlh->nlmsg_len, nlh->nlmsg_type, nlh->nlmsg_flags,
|
|
nlh->nlmsg_seq, nlh->nlmsg_pid);
|
|
d_printf(1, dev, "CRX: wimax message %zu bytes\n", msg_len);
|
|
d_dump(2, dev, msg_buf, msg_len);
|
|
|
|
result = wimax_dev->op_msg_from_user(wimax_dev, pipe_name,
|
|
msg_buf, msg_len, info);
|
|
error_noop:
|
|
error_not_ready:
|
|
mutex_unlock(&wimax_dev->mutex);
|
|
error_alloc:
|
|
kfree(pipe_name);
|
|
error_no_data:
|
|
dev_put(wimax_dev->net_dev);
|
|
error_no_wimax_dev:
|
|
d_fnend(3, NULL, "(skb %p info %p) = %d\n", skb, info, result);
|
|
return result;
|
|
}
|
|
|