![David Howells](/assets/img/avatar_default.png)
Pass credentials through dentry_open() so that the COW creds patch can have SELinux's flush_unauthorized_files() pass the appropriate creds back to itself when it opens its null chardev. The security_dentry_open() call also now takes a creds pointer, as does the dentry_open hook in struct security_operations. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: James Morris <jmorris@namei.org>
945 lines
20 KiB
C
945 lines
20 KiB
C
/*
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* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
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* Copyright (C) 2001 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com)
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* Licensed under the GPL
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*/
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#include <linux/console.h>
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#include <linux/ctype.h>
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#include <linux/interrupt.h>
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#include <linux/list.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/notifier.h>
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#include <linux/reboot.h>
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#include <linux/proc_fs.h>
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#include <linux/slab.h>
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#include <linux/syscalls.h>
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#include <linux/utsname.h>
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#include <linux/workqueue.h>
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#include <linux/mutex.h>
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#include <asm/uaccess.h>
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#include "init.h"
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#include "irq_kern.h"
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#include "irq_user.h"
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#include "kern_util.h"
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#include "mconsole.h"
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#include "mconsole_kern.h"
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#include "os.h"
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static int do_unlink_socket(struct notifier_block *notifier,
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unsigned long what, void *data)
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{
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return mconsole_unlink_socket();
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}
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static struct notifier_block reboot_notifier = {
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.notifier_call = do_unlink_socket,
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.priority = 0,
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};
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/* Safe without explicit locking for now. Tasklets provide their own
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* locking, and the interrupt handler is safe because it can't interrupt
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* itself and it can only happen on CPU 0.
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*/
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static LIST_HEAD(mc_requests);
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static void mc_work_proc(struct work_struct *unused)
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{
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struct mconsole_entry *req;
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unsigned long flags;
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while (!list_empty(&mc_requests)) {
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local_irq_save(flags);
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req = list_entry(mc_requests.next, struct mconsole_entry, list);
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list_del(&req->list);
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local_irq_restore(flags);
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req->request.cmd->handler(&req->request);
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kfree(req);
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}
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}
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static DECLARE_WORK(mconsole_work, mc_work_proc);
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static irqreturn_t mconsole_interrupt(int irq, void *dev_id)
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{
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/* long to avoid size mismatch warnings from gcc */
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long fd;
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struct mconsole_entry *new;
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static struct mc_request req; /* that's OK */
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fd = (long) dev_id;
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while (mconsole_get_request(fd, &req)) {
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if (req.cmd->context == MCONSOLE_INTR)
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(*req.cmd->handler)(&req);
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else {
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new = kmalloc(sizeof(*new), GFP_NOWAIT);
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if (new == NULL)
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mconsole_reply(&req, "Out of memory", 1, 0);
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else {
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new->request = req;
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new->request.regs = get_irq_regs()->regs;
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list_add(&new->list, &mc_requests);
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}
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}
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}
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if (!list_empty(&mc_requests))
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schedule_work(&mconsole_work);
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reactivate_fd(fd, MCONSOLE_IRQ);
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return IRQ_HANDLED;
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}
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void mconsole_version(struct mc_request *req)
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{
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char version[256];
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sprintf(version, "%s %s %s %s %s", utsname()->sysname,
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utsname()->nodename, utsname()->release, utsname()->version,
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utsname()->machine);
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mconsole_reply(req, version, 0, 0);
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}
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void mconsole_log(struct mc_request *req)
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{
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int len;
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char *ptr = req->request.data;
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ptr += strlen("log ");
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len = req->len - (ptr - req->request.data);
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printk(KERN_WARNING "%.*s", len, ptr);
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mconsole_reply(req, "", 0, 0);
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}
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/* This is a more convoluted version of mconsole_proc, which has some stability
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* problems; however, we need it fixed, because it is expected that UML users
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* mount HPPFS instead of procfs on /proc. And we want mconsole_proc to still
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* show the real procfs content, not the ones from hppfs.*/
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#if 0
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void mconsole_proc(struct mc_request *req)
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{
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struct nameidata nd;
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struct file_system_type *proc;
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struct super_block *super;
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struct file *file;
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int n, err;
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char *ptr = req->request.data, *buf;
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ptr += strlen("proc");
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while (isspace(*ptr)) ptr++;
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proc = get_fs_type("proc");
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if (proc == NULL) {
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mconsole_reply(req, "procfs not registered", 1, 0);
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goto out;
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}
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super = (*proc->get_sb)(proc, 0, NULL, NULL);
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put_filesystem(proc);
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if (super == NULL) {
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mconsole_reply(req, "Failed to get procfs superblock", 1, 0);
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goto out;
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}
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up_write(&super->s_umount);
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nd.path.dentry = super->s_root;
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nd.path.mnt = NULL;
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nd.flags = O_RDONLY + 1;
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nd.last_type = LAST_ROOT;
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/* START: it was experienced that the stability problems are closed
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* if commenting out these two calls + the below read cycle. To
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* make UML crash again, it was enough to readd either one.*/
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err = link_path_walk(ptr, &nd);
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if (err) {
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mconsole_reply(req, "Failed to look up file", 1, 0);
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goto out_kill;
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}
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file = dentry_open(nd.path.dentry, nd.path.mnt, O_RDONLY,
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current_cred());
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if (IS_ERR(file)) {
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mconsole_reply(req, "Failed to open file", 1, 0);
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goto out_kill;
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}
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/*END*/
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buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
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if (buf == NULL) {
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mconsole_reply(req, "Failed to allocate buffer", 1, 0);
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goto out_fput;
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}
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if ((file->f_op != NULL) && (file->f_op->read != NULL)) {
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do {
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n = (*file->f_op->read)(file, buf, PAGE_SIZE - 1,
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&file->f_pos);
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if (n >= 0) {
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buf[n] = '\0';
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mconsole_reply(req, buf, 0, (n > 0));
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}
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else {
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mconsole_reply(req, "Read of file failed",
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1, 0);
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goto out_free;
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}
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} while (n > 0);
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}
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else mconsole_reply(req, "", 0, 0);
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out_free:
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kfree(buf);
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out_fput:
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fput(file);
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out_kill:
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deactivate_super(super);
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out: ;
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}
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#endif
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void mconsole_proc(struct mc_request *req)
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{
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char path[64];
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char *buf;
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int len;
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int fd;
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int first_chunk = 1;
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char *ptr = req->request.data;
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ptr += strlen("proc");
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while (isspace(*ptr))
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ptr++;
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snprintf(path, sizeof(path), "/proc/%s", ptr);
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fd = sys_open(path, 0, 0);
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if (fd < 0) {
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mconsole_reply(req, "Failed to open file", 1, 0);
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printk(KERN_ERR "open %s: %d\n",path,fd);
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goto out;
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}
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buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
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if (buf == NULL) {
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mconsole_reply(req, "Failed to allocate buffer", 1, 0);
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goto out_close;
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}
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for (;;) {
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len = sys_read(fd, buf, PAGE_SIZE-1);
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if (len < 0) {
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mconsole_reply(req, "Read of file failed", 1, 0);
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goto out_free;
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}
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/* Begin the file content on his own line. */
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if (first_chunk) {
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mconsole_reply(req, "\n", 0, 1);
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first_chunk = 0;
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}
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if (len == PAGE_SIZE-1) {
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buf[len] = '\0';
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mconsole_reply(req, buf, 0, 1);
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} else {
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buf[len] = '\0';
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mconsole_reply(req, buf, 0, 0);
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break;
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}
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}
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out_free:
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kfree(buf);
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out_close:
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sys_close(fd);
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out:
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/* nothing */;
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}
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#define UML_MCONSOLE_HELPTEXT \
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"Commands: \n\
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version - Get kernel version \n\
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help - Print this message \n\
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halt - Halt UML \n\
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reboot - Reboot UML \n\
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config <dev>=<config> - Add a new device to UML; \n\
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same syntax as command line \n\
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config <dev> - Query the configuration of a device \n\
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remove <dev> - Remove a device from UML \n\
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sysrq <letter> - Performs the SysRq action controlled by the letter \n\
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cad - invoke the Ctrl-Alt-Del handler \n\
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stop - pause the UML; it will do nothing until it receives a 'go' \n\
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go - continue the UML after a 'stop' \n\
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log <string> - make UML enter <string> into the kernel log\n\
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proc <file> - returns the contents of the UML's /proc/<file>\n\
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stack <pid> - returns the stack of the specified pid\n\
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"
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void mconsole_help(struct mc_request *req)
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{
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mconsole_reply(req, UML_MCONSOLE_HELPTEXT, 0, 0);
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}
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void mconsole_halt(struct mc_request *req)
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{
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mconsole_reply(req, "", 0, 0);
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machine_halt();
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}
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void mconsole_reboot(struct mc_request *req)
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{
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mconsole_reply(req, "", 0, 0);
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machine_restart(NULL);
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}
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void mconsole_cad(struct mc_request *req)
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{
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mconsole_reply(req, "", 0, 0);
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ctrl_alt_del();
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}
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void mconsole_go(struct mc_request *req)
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{
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mconsole_reply(req, "Not stopped", 1, 0);
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}
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void mconsole_stop(struct mc_request *req)
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{
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deactivate_fd(req->originating_fd, MCONSOLE_IRQ);
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os_set_fd_block(req->originating_fd, 1);
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mconsole_reply(req, "stopped", 0, 0);
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for (;;) {
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if (!mconsole_get_request(req->originating_fd, req))
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continue;
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if (req->cmd->handler == mconsole_go)
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break;
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if (req->cmd->handler == mconsole_stop) {
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mconsole_reply(req, "Already stopped", 1, 0);
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continue;
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}
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if (req->cmd->handler == mconsole_sysrq) {
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struct pt_regs *old_regs;
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old_regs = set_irq_regs((struct pt_regs *)&req->regs);
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mconsole_sysrq(req);
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set_irq_regs(old_regs);
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continue;
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}
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(*req->cmd->handler)(req);
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}
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os_set_fd_block(req->originating_fd, 0);
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reactivate_fd(req->originating_fd, MCONSOLE_IRQ);
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mconsole_reply(req, "", 0, 0);
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}
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static DEFINE_SPINLOCK(mc_devices_lock);
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static LIST_HEAD(mconsole_devices);
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void mconsole_register_dev(struct mc_device *new)
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{
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spin_lock(&mc_devices_lock);
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BUG_ON(!list_empty(&new->list));
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list_add(&new->list, &mconsole_devices);
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spin_unlock(&mc_devices_lock);
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}
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static struct mc_device *mconsole_find_dev(char *name)
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{
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struct list_head *ele;
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struct mc_device *dev;
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list_for_each(ele, &mconsole_devices) {
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dev = list_entry(ele, struct mc_device, list);
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if (!strncmp(name, dev->name, strlen(dev->name)))
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return dev;
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}
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return NULL;
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}
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#define UNPLUGGED_PER_PAGE \
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((PAGE_SIZE - sizeof(struct list_head)) / sizeof(unsigned long))
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struct unplugged_pages {
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struct list_head list;
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void *pages[UNPLUGGED_PER_PAGE];
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};
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static DEFINE_MUTEX(plug_mem_mutex);
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static unsigned long long unplugged_pages_count = 0;
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static LIST_HEAD(unplugged_pages);
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static int unplug_index = UNPLUGGED_PER_PAGE;
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static int mem_config(char *str, char **error_out)
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{
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unsigned long long diff;
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int err = -EINVAL, i, add;
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char *ret;
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if (str[0] != '=') {
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*error_out = "Expected '=' after 'mem'";
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goto out;
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}
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str++;
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if (str[0] == '-')
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add = 0;
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else if (str[0] == '+') {
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add = 1;
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}
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else {
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*error_out = "Expected increment to start with '-' or '+'";
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goto out;
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}
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str++;
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diff = memparse(str, &ret);
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if (*ret != '\0') {
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*error_out = "Failed to parse memory increment";
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goto out;
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}
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diff /= PAGE_SIZE;
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mutex_lock(&plug_mem_mutex);
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for (i = 0; i < diff; i++) {
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struct unplugged_pages *unplugged;
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void *addr;
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if (add) {
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if (list_empty(&unplugged_pages))
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break;
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unplugged = list_entry(unplugged_pages.next,
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struct unplugged_pages, list);
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if (unplug_index > 0)
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addr = unplugged->pages[--unplug_index];
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else {
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list_del(&unplugged->list);
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addr = unplugged;
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unplug_index = UNPLUGGED_PER_PAGE;
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}
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|
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free_page((unsigned long) addr);
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unplugged_pages_count--;
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}
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else {
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struct page *page;
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page = alloc_page(GFP_ATOMIC);
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if (page == NULL)
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break;
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unplugged = page_address(page);
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if (unplug_index == UNPLUGGED_PER_PAGE) {
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list_add(&unplugged->list, &unplugged_pages);
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unplug_index = 0;
|
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}
|
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else {
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struct list_head *entry = unplugged_pages.next;
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addr = unplugged;
|
|
|
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unplugged = list_entry(entry,
|
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struct unplugged_pages,
|
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list);
|
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err = os_drop_memory(addr, PAGE_SIZE);
|
|
if (err) {
|
|
printk(KERN_ERR "Failed to release "
|
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"memory - errno = %d\n", err);
|
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*error_out = "Failed to release memory";
|
|
goto out_unlock;
|
|
}
|
|
unplugged->pages[unplug_index++] = addr;
|
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}
|
|
|
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unplugged_pages_count++;
|
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}
|
|
}
|
|
|
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err = 0;
|
|
out_unlock:
|
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mutex_unlock(&plug_mem_mutex);
|
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out:
|
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return err;
|
|
}
|
|
|
|
static int mem_get_config(char *name, char *str, int size, char **error_out)
|
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{
|
|
char buf[sizeof("18446744073709551615")];
|
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int len = 0;
|
|
|
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sprintf(buf, "%ld", uml_physmem);
|
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CONFIG_CHUNK(str, size, len, buf, 1);
|
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|
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return len;
|
|
}
|
|
|
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static int mem_id(char **str, int *start_out, int *end_out)
|
|
{
|
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*start_out = 0;
|
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*end_out = 0;
|
|
|
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return 0;
|
|
}
|
|
|
|
static int mem_remove(int n, char **error_out)
|
|
{
|
|
*error_out = "Memory doesn't support the remove operation";
|
|
return -EBUSY;
|
|
}
|
|
|
|
static struct mc_device mem_mc = {
|
|
.list = LIST_HEAD_INIT(mem_mc.list),
|
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.name = "mem",
|
|
.config = mem_config,
|
|
.get_config = mem_get_config,
|
|
.id = mem_id,
|
|
.remove = mem_remove,
|
|
};
|
|
|
|
static int __init mem_mc_init(void)
|
|
{
|
|
if (can_drop_memory())
|
|
mconsole_register_dev(&mem_mc);
|
|
else printk(KERN_ERR "Can't release memory to the host - memory "
|
|
"hotplug won't be supported\n");
|
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return 0;
|
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}
|
|
|
|
__initcall(mem_mc_init);
|
|
|
|
#define CONFIG_BUF_SIZE 64
|
|
|
|
static void mconsole_get_config(int (*get_config)(char *, char *, int,
|
|
char **),
|
|
struct mc_request *req, char *name)
|
|
{
|
|
char default_buf[CONFIG_BUF_SIZE], *error, *buf;
|
|
int n, size;
|
|
|
|
if (get_config == NULL) {
|
|
mconsole_reply(req, "No get_config routine defined", 1, 0);
|
|
return;
|
|
}
|
|
|
|
error = NULL;
|
|
size = ARRAY_SIZE(default_buf);
|
|
buf = default_buf;
|
|
|
|
while (1) {
|
|
n = (*get_config)(name, buf, size, &error);
|
|
if (error != NULL) {
|
|
mconsole_reply(req, error, 1, 0);
|
|
goto out;
|
|
}
|
|
|
|
if (n <= size) {
|
|
mconsole_reply(req, buf, 0, 0);
|
|
goto out;
|
|
}
|
|
|
|
if (buf != default_buf)
|
|
kfree(buf);
|
|
|
|
size = n;
|
|
buf = kmalloc(size, GFP_KERNEL);
|
|
if (buf == NULL) {
|
|
mconsole_reply(req, "Failed to allocate buffer", 1, 0);
|
|
return;
|
|
}
|
|
}
|
|
out:
|
|
if (buf != default_buf)
|
|
kfree(buf);
|
|
}
|
|
|
|
void mconsole_config(struct mc_request *req)
|
|
{
|
|
struct mc_device *dev;
|
|
char *ptr = req->request.data, *name, *error_string = "";
|
|
int err;
|
|
|
|
ptr += strlen("config");
|
|
while (isspace(*ptr))
|
|
ptr++;
|
|
dev = mconsole_find_dev(ptr);
|
|
if (dev == NULL) {
|
|
mconsole_reply(req, "Bad configuration option", 1, 0);
|
|
return;
|
|
}
|
|
|
|
name = &ptr[strlen(dev->name)];
|
|
ptr = name;
|
|
while ((*ptr != '=') && (*ptr != '\0'))
|
|
ptr++;
|
|
|
|
if (*ptr == '=') {
|
|
err = (*dev->config)(name, &error_string);
|
|
mconsole_reply(req, error_string, err, 0);
|
|
}
|
|
else mconsole_get_config(dev->get_config, req, name);
|
|
}
|
|
|
|
void mconsole_remove(struct mc_request *req)
|
|
{
|
|
struct mc_device *dev;
|
|
char *ptr = req->request.data, *err_msg = "";
|
|
char error[256];
|
|
int err, start, end, n;
|
|
|
|
ptr += strlen("remove");
|
|
while (isspace(*ptr)) ptr++;
|
|
dev = mconsole_find_dev(ptr);
|
|
if (dev == NULL) {
|
|
mconsole_reply(req, "Bad remove option", 1, 0);
|
|
return;
|
|
}
|
|
|
|
ptr = &ptr[strlen(dev->name)];
|
|
|
|
err = 1;
|
|
n = (*dev->id)(&ptr, &start, &end);
|
|
if (n < 0) {
|
|
err_msg = "Couldn't parse device number";
|
|
goto out;
|
|
}
|
|
else if ((n < start) || (n > end)) {
|
|
sprintf(error, "Invalid device number - must be between "
|
|
"%d and %d", start, end);
|
|
err_msg = error;
|
|
goto out;
|
|
}
|
|
|
|
err_msg = NULL;
|
|
err = (*dev->remove)(n, &err_msg);
|
|
switch(err) {
|
|
case 0:
|
|
err_msg = "";
|
|
break;
|
|
case -ENODEV:
|
|
if (err_msg == NULL)
|
|
err_msg = "Device doesn't exist";
|
|
break;
|
|
case -EBUSY:
|
|
if (err_msg == NULL)
|
|
err_msg = "Device is currently open";
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
out:
|
|
mconsole_reply(req, err_msg, err, 0);
|
|
}
|
|
|
|
struct mconsole_output {
|
|
struct list_head list;
|
|
struct mc_request *req;
|
|
};
|
|
|
|
static DEFINE_SPINLOCK(client_lock);
|
|
static LIST_HEAD(clients);
|
|
static char console_buf[MCONSOLE_MAX_DATA];
|
|
|
|
static void console_write(struct console *console, const char *string,
|
|
unsigned int len)
|
|
{
|
|
struct list_head *ele;
|
|
int n;
|
|
|
|
if (list_empty(&clients))
|
|
return;
|
|
|
|
while (len > 0) {
|
|
n = min((size_t) len, ARRAY_SIZE(console_buf));
|
|
strncpy(console_buf, string, n);
|
|
string += n;
|
|
len -= n;
|
|
|
|
list_for_each(ele, &clients) {
|
|
struct mconsole_output *entry;
|
|
|
|
entry = list_entry(ele, struct mconsole_output, list);
|
|
mconsole_reply_len(entry->req, console_buf, n, 0, 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
static struct console mc_console = { .name = "mc",
|
|
.write = console_write,
|
|
.flags = CON_ENABLED,
|
|
.index = -1 };
|
|
|
|
static int mc_add_console(void)
|
|
{
|
|
register_console(&mc_console);
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(mc_add_console);
|
|
|
|
static void with_console(struct mc_request *req, void (*proc)(void *),
|
|
void *arg)
|
|
{
|
|
struct mconsole_output entry;
|
|
unsigned long flags;
|
|
|
|
entry.req = req;
|
|
spin_lock_irqsave(&client_lock, flags);
|
|
list_add(&entry.list, &clients);
|
|
spin_unlock_irqrestore(&client_lock, flags);
|
|
|
|
(*proc)(arg);
|
|
|
|
mconsole_reply_len(req, "", 0, 0, 0);
|
|
|
|
spin_lock_irqsave(&client_lock, flags);
|
|
list_del(&entry.list);
|
|
spin_unlock_irqrestore(&client_lock, flags);
|
|
}
|
|
|
|
#ifdef CONFIG_MAGIC_SYSRQ
|
|
|
|
#include <linux/sysrq.h>
|
|
|
|
static void sysrq_proc(void *arg)
|
|
{
|
|
char *op = arg;
|
|
handle_sysrq(*op, NULL);
|
|
}
|
|
|
|
void mconsole_sysrq(struct mc_request *req)
|
|
{
|
|
char *ptr = req->request.data;
|
|
|
|
ptr += strlen("sysrq");
|
|
while (isspace(*ptr)) ptr++;
|
|
|
|
/*
|
|
* With 'b', the system will shut down without a chance to reply,
|
|
* so in this case, we reply first.
|
|
*/
|
|
if (*ptr == 'b')
|
|
mconsole_reply(req, "", 0, 0);
|
|
|
|
with_console(req, sysrq_proc, ptr);
|
|
}
|
|
#else
|
|
void mconsole_sysrq(struct mc_request *req)
|
|
{
|
|
mconsole_reply(req, "Sysrq not compiled in", 1, 0);
|
|
}
|
|
#endif
|
|
|
|
static void stack_proc(void *arg)
|
|
{
|
|
struct task_struct *from = current, *to = arg;
|
|
|
|
to->thread.saved_task = from;
|
|
switch_to(from, to, from);
|
|
}
|
|
|
|
/*
|
|
* Mconsole stack trace
|
|
* Added by Allan Graves, Jeff Dike
|
|
* Dumps a stacks registers to the linux console.
|
|
* Usage stack <pid>.
|
|
*/
|
|
void mconsole_stack(struct mc_request *req)
|
|
{
|
|
char *ptr = req->request.data;
|
|
int pid_requested= -1;
|
|
struct task_struct *to = NULL;
|
|
|
|
/*
|
|
* Would be nice:
|
|
* 1) Send showregs output to mconsole.
|
|
* 2) Add a way to stack dump all pids.
|
|
*/
|
|
|
|
ptr += strlen("stack");
|
|
while (isspace(*ptr))
|
|
ptr++;
|
|
|
|
/*
|
|
* Should really check for multiple pids or reject bad args here
|
|
*/
|
|
/* What do the arguments in mconsole_reply mean? */
|
|
if (sscanf(ptr, "%d", &pid_requested) == 0) {
|
|
mconsole_reply(req, "Please specify a pid", 1, 0);
|
|
return;
|
|
}
|
|
|
|
to = find_task_by_pid_ns(pid_requested, &init_pid_ns);
|
|
if ((to == NULL) || (pid_requested == 0)) {
|
|
mconsole_reply(req, "Couldn't find that pid", 1, 0);
|
|
return;
|
|
}
|
|
with_console(req, stack_proc, to);
|
|
}
|
|
|
|
/*
|
|
* Changed by mconsole_setup, which is __setup, and called before SMP is
|
|
* active.
|
|
*/
|
|
static char *notify_socket = NULL;
|
|
|
|
static int __init mconsole_init(void)
|
|
{
|
|
/* long to avoid size mismatch warnings from gcc */
|
|
long sock;
|
|
int err;
|
|
char file[256];
|
|
|
|
if (umid_file_name("mconsole", file, sizeof(file)))
|
|
return -1;
|
|
snprintf(mconsole_socket_name, sizeof(file), "%s", file);
|
|
|
|
sock = os_create_unix_socket(file, sizeof(file), 1);
|
|
if (sock < 0) {
|
|
printk(KERN_ERR "Failed to initialize management console\n");
|
|
return 1;
|
|
}
|
|
if (os_set_fd_block(sock, 0))
|
|
goto out;
|
|
|
|
register_reboot_notifier(&reboot_notifier);
|
|
|
|
err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt,
|
|
IRQF_DISABLED | IRQF_SHARED | IRQF_SAMPLE_RANDOM,
|
|
"mconsole", (void *)sock);
|
|
if (err) {
|
|
printk(KERN_ERR "Failed to get IRQ for management console\n");
|
|
goto out;
|
|
}
|
|
|
|
if (notify_socket != NULL) {
|
|
notify_socket = kstrdup(notify_socket, GFP_KERNEL);
|
|
if (notify_socket != NULL)
|
|
mconsole_notify(notify_socket, MCONSOLE_SOCKET,
|
|
mconsole_socket_name,
|
|
strlen(mconsole_socket_name) + 1);
|
|
else printk(KERN_ERR "mconsole_setup failed to strdup "
|
|
"string\n");
|
|
}
|
|
|
|
printk(KERN_INFO "mconsole (version %d) initialized on %s\n",
|
|
MCONSOLE_VERSION, mconsole_socket_name);
|
|
return 0;
|
|
|
|
out:
|
|
os_close_file(sock);
|
|
return 1;
|
|
}
|
|
|
|
__initcall(mconsole_init);
|
|
|
|
static int write_proc_mconsole(struct file *file, const char __user *buffer,
|
|
unsigned long count, void *data)
|
|
{
|
|
char *buf;
|
|
|
|
buf = kmalloc(count + 1, GFP_KERNEL);
|
|
if (buf == NULL)
|
|
return -ENOMEM;
|
|
|
|
if (copy_from_user(buf, buffer, count)) {
|
|
count = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
buf[count] = '\0';
|
|
|
|
mconsole_notify(notify_socket, MCONSOLE_USER_NOTIFY, buf, count);
|
|
out:
|
|
kfree(buf);
|
|
return count;
|
|
}
|
|
|
|
static int create_proc_mconsole(void)
|
|
{
|
|
struct proc_dir_entry *ent;
|
|
|
|
if (notify_socket == NULL)
|
|
return 0;
|
|
|
|
ent = create_proc_entry("mconsole", S_IFREG | 0200, NULL);
|
|
if (ent == NULL) {
|
|
printk(KERN_INFO "create_proc_mconsole : create_proc_entry "
|
|
"failed\n");
|
|
return 0;
|
|
}
|
|
|
|
ent->read_proc = NULL;
|
|
ent->write_proc = write_proc_mconsole;
|
|
return 0;
|
|
}
|
|
|
|
static DEFINE_SPINLOCK(notify_spinlock);
|
|
|
|
void lock_notify(void)
|
|
{
|
|
spin_lock(¬ify_spinlock);
|
|
}
|
|
|
|
void unlock_notify(void)
|
|
{
|
|
spin_unlock(¬ify_spinlock);
|
|
}
|
|
|
|
__initcall(create_proc_mconsole);
|
|
|
|
#define NOTIFY "notify:"
|
|
|
|
static int mconsole_setup(char *str)
|
|
{
|
|
if (!strncmp(str, NOTIFY, strlen(NOTIFY))) {
|
|
str += strlen(NOTIFY);
|
|
notify_socket = str;
|
|
}
|
|
else printk(KERN_ERR "mconsole_setup : Unknown option - '%s'\n", str);
|
|
return 1;
|
|
}
|
|
|
|
__setup("mconsole=", mconsole_setup);
|
|
|
|
__uml_help(mconsole_setup,
|
|
"mconsole=notify:<socket>\n"
|
|
" Requests that the mconsole driver send a message to the named Unix\n"
|
|
" socket containing the name of the mconsole socket. This also serves\n"
|
|
" to notify outside processes when UML has booted far enough to respond\n"
|
|
" to mconsole requests.\n\n"
|
|
);
|
|
|
|
static int notify_panic(struct notifier_block *self, unsigned long unused1,
|
|
void *ptr)
|
|
{
|
|
char *message = ptr;
|
|
|
|
if (notify_socket == NULL)
|
|
return 0;
|
|
|
|
mconsole_notify(notify_socket, MCONSOLE_PANIC, message,
|
|
strlen(message) + 1);
|
|
return 0;
|
|
}
|
|
|
|
static struct notifier_block panic_exit_notifier = {
|
|
.notifier_call = notify_panic,
|
|
.next = NULL,
|
|
.priority = 1
|
|
};
|
|
|
|
static int add_notifier(void)
|
|
{
|
|
atomic_notifier_chain_register(&panic_notifier_list,
|
|
&panic_exit_notifier);
|
|
return 0;
|
|
}
|
|
|
|
__initcall(add_notifier);
|
|
|
|
char *mconsole_notify_socket(void)
|
|
{
|
|
return notify_socket;
|
|
}
|
|
|
|
EXPORT_SYMBOL(mconsole_notify_socket);
|