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path: root/kernel/power/tuxonice_netlink.c
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Diffstat (limited to 'kernel/power/tuxonice_netlink.c')
-rw-r--r--kernel/power/tuxonice_netlink.c324
1 files changed, 0 insertions, 324 deletions
diff --git a/kernel/power/tuxonice_netlink.c b/kernel/power/tuxonice_netlink.c
deleted file mode 100644
index 78bd31b05..000000000
--- a/kernel/power/tuxonice_netlink.c
+++ /dev/null
@@ -1,324 +0,0 @@
-/*
- * kernel/power/tuxonice_netlink.c
- *
- * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
- *
- * This file is released under the GPLv2.
- *
- * Functions for communicating with a userspace helper via netlink.
- */
-
-#include <linux/suspend.h>
-#include <linux/sched.h>
-#include <linux/kmod.h>
-#include "tuxonice_netlink.h"
-#include "tuxonice.h"
-#include "tuxonice_modules.h"
-#include "tuxonice_alloc.h"
-#include "tuxonice_builtin.h"
-
-static struct user_helper_data *uhd_list;
-
-/*
- * Refill our pool of SKBs for use in emergencies (eg, when eating memory and
- * none can be allocated).
- */
-static void toi_fill_skb_pool(struct user_helper_data *uhd)
-{
- while (uhd->pool_level < uhd->pool_limit) {
- struct sk_buff *new_skb =
- alloc_skb(NLMSG_SPACE(uhd->skb_size), TOI_ATOMIC_GFP);
-
- if (!new_skb)
- break;
-
- new_skb->next = uhd->emerg_skbs;
- uhd->emerg_skbs = new_skb;
- uhd->pool_level++;
- }
-}
-
-/*
- * Try to allocate a single skb. If we can't get one, try to use one from
- * our pool.
- */
-static struct sk_buff *toi_get_skb(struct user_helper_data *uhd)
-{
- struct sk_buff *skb =
- alloc_skb(NLMSG_SPACE(uhd->skb_size), TOI_ATOMIC_GFP);
-
- if (skb)
- return skb;
-
- skb = uhd->emerg_skbs;
- if (skb) {
- uhd->pool_level--;
- uhd->emerg_skbs = skb->next;
- skb->next = NULL;
- }
-
- return skb;
-}
-
-void toi_send_netlink_message(struct user_helper_data *uhd,
- int type, void *params, size_t len)
-{
- struct sk_buff *skb;
- struct nlmsghdr *nlh;
- void *dest;
- struct task_struct *t;
-
- if (uhd->pid == -1)
- return;
-
- if (uhd->debug)
- printk(KERN_ERR "toi_send_netlink_message: Send "
- "message type %d.\n", type);
-
- skb = toi_get_skb(uhd);
- if (!skb) {
- printk(KERN_INFO "toi_netlink: Can't allocate skb!\n");
- return;
- }
-
- nlh = nlmsg_put(skb, 0, uhd->sock_seq, type, len, 0);
- uhd->sock_seq++;
-
- dest = NLMSG_DATA(nlh);
- if (params && len > 0)
- memcpy(dest, params, len);
-
- netlink_unicast(uhd->nl, skb, uhd->pid, 0);
-
- toi_read_lock_tasklist();
- t = find_task_by_pid_ns(uhd->pid, &init_pid_ns);
- if (!t) {
- toi_read_unlock_tasklist();
- if (uhd->pid > -1)
- printk(KERN_INFO "Hmm. Can't find the userspace task"
- " %d.\n", uhd->pid);
- return;
- }
- wake_up_process(t);
- toi_read_unlock_tasklist();
-
- yield();
-}
-
-static void send_whether_debugging(struct user_helper_data *uhd)
-{
- static u8 is_debugging = 1;
-
- toi_send_netlink_message(uhd, NETLINK_MSG_IS_DEBUGGING,
- &is_debugging, sizeof(u8));
-}
-
-/*
- * Set the PF_NOFREEZE flag on the given process to ensure it can run whilst we
- * are hibernating.
- */
-static int nl_set_nofreeze(struct user_helper_data *uhd, __u32 pid)
-{
- struct task_struct *t;
-
- if (uhd->debug)
- printk(KERN_ERR "nl_set_nofreeze for pid %d.\n", pid);
-
- toi_read_lock_tasklist();
- t = find_task_by_pid_ns(pid, &init_pid_ns);
- if (!t) {
- toi_read_unlock_tasklist();
- printk(KERN_INFO "Strange. Can't find the userspace task %d.\n",
- pid);
- return -EINVAL;
- }
-
- t->flags |= PF_NOFREEZE;
-
- toi_read_unlock_tasklist();
- uhd->pid = pid;
-
- toi_send_netlink_message(uhd, NETLINK_MSG_NOFREEZE_ACK, NULL, 0);
-
- return 0;
-}
-
-/*
- * Called when the userspace process has informed us that it's ready to roll.
- */
-static int nl_ready(struct user_helper_data *uhd, u32 version)
-{
- if (version != uhd->interface_version) {
- printk(KERN_INFO "%s userspace process using invalid interface"
- " version (%d - kernel wants %d). Trying to "
- "continue without it.\n",
- uhd->name, version, uhd->interface_version);
- if (uhd->not_ready)
- uhd->not_ready();
- return -EINVAL;
- }
-
- complete(&uhd->wait_for_process);
-
- return 0;
-}
-
-void toi_netlink_close_complete(struct user_helper_data *uhd)
-{
- if (uhd->nl) {
- netlink_kernel_release(uhd->nl);
- uhd->nl = NULL;
- }
-
- while (uhd->emerg_skbs) {
- struct sk_buff *next = uhd->emerg_skbs->next;
- kfree_skb(uhd->emerg_skbs);
- uhd->emerg_skbs = next;
- }
-
- uhd->pid = -1;
-}
-
-static int toi_nl_gen_rcv_msg(struct user_helper_data *uhd,
- struct sk_buff *skb, struct nlmsghdr *nlh)
-{
- int type = nlh->nlmsg_type;
- int *data;
- int err;
-
- if (uhd->debug)
- printk(KERN_ERR "toi_user_rcv_skb: Received message %d.\n",
- type);
-
- /* Let the more specific handler go first. It returns
- * 1 for valid messages that it doesn't know. */
- err = uhd->rcv_msg(skb, nlh);
- if (err != 1)
- return err;
-
- /* Only allow one task to receive NOFREEZE privileges */
- if (type == NETLINK_MSG_NOFREEZE_ME && uhd->pid != -1) {
- printk(KERN_INFO "Received extra nofreeze me requests.\n");
- return -EBUSY;
- }
-
- data = NLMSG_DATA(nlh);
-
- switch (type) {
- case NETLINK_MSG_NOFREEZE_ME:
- return nl_set_nofreeze(uhd, nlh->nlmsg_pid);
- case NETLINK_MSG_GET_DEBUGGING:
- send_whether_debugging(uhd);
- return 0;
- case NETLINK_MSG_READY:
- if (nlh->nlmsg_len != NLMSG_LENGTH(sizeof(u32))) {
- printk(KERN_INFO "Invalid ready mesage.\n");
- if (uhd->not_ready)
- uhd->not_ready();
- return -EINVAL;
- }
- return nl_ready(uhd, (u32) *data);
- case NETLINK_MSG_CLEANUP:
- toi_netlink_close_complete(uhd);
- return 0;
- }
-
- return -EINVAL;
-}
-
-static void toi_user_rcv_skb(struct sk_buff *skb)
-{
- int err;
- struct nlmsghdr *nlh;
- struct user_helper_data *uhd = uhd_list;
-
- while (uhd && uhd->netlink_id != skb->sk->sk_protocol)
- uhd = uhd->next;
-
- if (!uhd)
- return;
-
- while (skb->len >= NLMSG_SPACE(0)) {
- u32 rlen;
-
- nlh = (struct nlmsghdr *) skb->data;
- if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
- return;
-
- rlen = NLMSG_ALIGN(nlh->nlmsg_len);
- if (rlen > skb->len)
- rlen = skb->len;
-
- err = toi_nl_gen_rcv_msg(uhd, skb, nlh);
- if (err)
- netlink_ack(skb, nlh, err);
- else if (nlh->nlmsg_flags & NLM_F_ACK)
- netlink_ack(skb, nlh, 0);
- skb_pull(skb, rlen);
- }
-}
-
-static int netlink_prepare(struct user_helper_data *uhd)
-{
- struct netlink_kernel_cfg cfg = {
- .groups = 0,
- .input = toi_user_rcv_skb,
- };
-
- uhd->next = uhd_list;
- uhd_list = uhd;
-
- uhd->sock_seq = 0x42c0ffee;
- uhd->nl = netlink_kernel_create(&init_net, uhd->netlink_id, &cfg);
- if (!uhd->nl) {
- printk(KERN_INFO "Failed to allocate netlink socket for %s.\n",
- uhd->name);
- return -ENOMEM;
- }
-
- toi_fill_skb_pool(uhd);
-
- return 0;
-}
-
-void toi_netlink_close(struct user_helper_data *uhd)
-{
- struct task_struct *t;
-
- toi_read_lock_tasklist();
- t = find_task_by_pid_ns(uhd->pid, &init_pid_ns);
- if (t)
- t->flags &= ~PF_NOFREEZE;
- toi_read_unlock_tasklist();
-
- toi_send_netlink_message(uhd, NETLINK_MSG_CLEANUP, NULL, 0);
-}
-int toi_netlink_setup(struct user_helper_data *uhd)
-{
- /* In case userui didn't cleanup properly on us */
- toi_netlink_close_complete(uhd);
-
- if (netlink_prepare(uhd) < 0) {
- printk(KERN_INFO "Netlink prepare failed.\n");
- return 1;
- }
-
- if (toi_launch_userspace_program(uhd->program, uhd->netlink_id,
- UMH_WAIT_EXEC, uhd->debug) < 0) {
- printk(KERN_INFO "Launch userspace program failed.\n");
- toi_netlink_close_complete(uhd);
- return 1;
- }
-
- /* Wait 2 seconds for the userspace process to make contact */
- wait_for_completion_timeout(&uhd->wait_for_process, 2*HZ);
-
- if (uhd->pid == -1) {
- printk(KERN_INFO "%s: Failed to contact userspace process.\n",
- uhd->name);
- toi_netlink_close_complete(uhd);
- return 1;
- }
-
- return 0;
-}
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