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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/net/wimax/op-msg.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/net/wimax/op-msg.c')
-rw-r--r-- | kernel/net/wimax/op-msg.c | 407 |
1 files changed, 407 insertions, 0 deletions
diff --git a/kernel/net/wimax/op-msg.c b/kernel/net/wimax/op-msg.c new file mode 100644 index 000000000..54aa14693 --- /dev/null +++ b/kernel/net/wimax/op-msg.c @@ -0,0 +1,407 @@ +/* + * 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; +} + |