timod.c

Linux内核源代码 为压缩文件 是<<Linux内核>>一书中的源代码

/* $Id: timod.c,v 1.10 2000/07/28 12:15:02 davem Exp $
 * timod.c: timod emulation.
 *
 * Copyright (C) 1998 Patrik Rak ([e-mail])
 *
 * Streams & timod emulation based on code
 * Copyright (C) 1995, 1996 Mike Jagdis ([e-mail])
 *
 */
 
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/ioctl.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/netdevice.h>
#include <linux/poll.h>

#include <net/sock.h>

#include <asm/uaccess.h>
#include <asm/termios.h>

#include "conv.h"
#include "socksys.h"

extern asmlinkage int sys_ioctl(unsigned int fd, unsigned int cmd, 
	unsigned long arg);
extern asmlinkage int sys32_ioctl(unsigned int fd, unsigned int cmd,
	u32 arg);
asmlinkage int solaris_ioctl(unsigned int fd, unsigned int cmd, u32 arg);

spinlock_t timod_pagelock = SPIN_LOCK_UNLOCKED;
static char * page = NULL ;

#ifndef DEBUG_SOLARIS_KMALLOC

#define mykmalloc kmalloc
#define mykfree kfree

#else

void * mykmalloc(size_t s, int gfp)
{
	static char * page;
	static size_t free = 0;
	void * r;
	s = ((s + 63) & ~63);
	if( s > PAGE_SIZE ) {
		SOLD("too big size, calling real kmalloc");
		return kmalloc(s, gfp);
	}
	if( s > free ) {
		/* we are wasting memory, but we don't care */
		page = (char *)__get_free_page(gfp);
		free = PAGE_SIZE;
	}
	r = page;
	page += s;
	free -= s;
	return r;
}

void mykfree(void *p)
{
}

#endif

#ifndef DEBUG_SOLARIS

#define BUF_SIZE	PAGE_SIZE
#define PUT_MAGIC(a,m)
#define SCHECK_MAGIC(a,m)
#define BUF_OFFSET	0
#define MKCTL_TRAILER	0

#else

#define BUF_SIZE	(PAGE_SIZE-2*sizeof(u64))
#define BUFPAGE_MAGIC	0xBADC0DEDDEADBABEL
#define MKCTL_MAGIC	0xDEADBABEBADC0DEDL
#define PUT_MAGIC(a,m)	do{(*(u64*)(a))=(m);}while(0)
#define SCHECK_MAGIC(a,m)	do{if((*(u64*)(a))!=(m))printk("%s,%u,%s(): magic %08x at %p corrupted!\n",\
				__FILE__,__LINE__,__FUNCTION__,(m),(a));}while(0)
#define BUF_OFFSET	sizeof(u64)
#define MKCTL_TRAILER	sizeof(u64)

#endif

static char *getpage( void )
{
	char *r;
	SOLD("getting page");
	spin_lock(&timod_pagelock);
	if (page) {
		r = page;
		page = NULL;
		spin_unlock(&timod_pagelock);
		SOLD("got cached");
		return r + BUF_OFFSET;
	}
	spin_unlock(&timod_pagelock);
	SOLD("getting new");
	r = (char *)__get_free_page(GFP_KERNEL);
	PUT_MAGIC(r,BUFPAGE_MAGIC);
	PUT_MAGIC(r+PAGE_SIZE-sizeof(u64),BUFPAGE_MAGIC);
	return r + BUF_OFFSET;
}

static void putpage(char *p)
{
	SOLD("putting page");
	p = p - BUF_OFFSET;
	SCHECK_MAGIC(p,BUFPAGE_MAGIC);
	SCHECK_MAGIC(p+PAGE_SIZE-sizeof(u64),BUFPAGE_MAGIC);
	spin_lock(&timod_pagelock);
	if (page) {
		spin_unlock(&timod_pagelock);
		free_page((unsigned long)p);
		SOLD("freed it");
	} else {
		page = p;
		spin_unlock(&timod_pagelock);
		SOLD("cached it");
	}
}

static struct T_primsg *timod_mkctl(int size)
{
	struct T_primsg *it;

	SOLD("creating primsg");
	it = (struct T_primsg *)mykmalloc(size+sizeof(*it)-sizeof(s32)+2*MKCTL_TRAILER, GFP_KERNEL);
	if (it) {
		SOLD("got it");
		it->pri = MSG_HIPRI;
		it->length = size;
		PUT_MAGIC((char*)((u64)(((char *)&it->type)+size+7)&~7),MKCTL_MAGIC);
	}
	return it;
}

static void timod_wake_socket(unsigned int fd)
{
	struct socket *sock;

	SOLD("wakeing socket");
	sock = &current->files->fd[fd]->f_dentry->d_inode->u.socket_i;
	wake_up_interruptible(&sock->wait);
	read_lock(&sock->sk->callback_lock);
	if (sock->fasync_list && !test_bit(SOCK_ASYNC_WAITDATA, &sock->flags))
		__kill_fasync(sock->fasync_list, SIGIO, POLL_IN);
	read_unlock(&sock->sk->callback_lock);
	SOLD("done");
}

static void timod_queue(unsigned int fd, struct T_primsg *it)
{
	struct sol_socket_struct *sock;

	SOLD("queuing primsg");
	sock = (struct sol_socket_struct *)current->files->fd[fd]->private_data;
	it->next = sock->pfirst;
	sock->pfirst = it;
	if (!sock->plast)
		sock->plast = it;
	timod_wake_socket(fd);
	SOLD("done");
}

static void timod_queue_end(unsigned int fd, struct T_primsg *it)
{
	struct sol_socket_struct *sock;

	SOLD("queuing primsg at end");
	sock = (struct sol_socket_struct *)current->files->fd[fd]->private_data;
	it->next = NULL;
	if (sock->plast)
		sock->plast->next = it;
	else
		sock->pfirst = it;
	sock->plast = it;
	SOLD("done");
}

static void timod_error(unsigned int fd, int prim, int terr, int uerr)
{
	struct T_primsg *it;
	
	SOLD("making error");
	it = timod_mkctl(sizeof(struct T_error_ack));
	if (it) {
		struct T_error_ack *err = (struct T_error_ack *)&it->type;
		
		SOLD("got it");
		err->PRIM_type = T_ERROR_ACK;
		err->ERROR_prim = prim;
		err->TLI_error = terr;
		err->UNIX_error = uerr; /* FIXME: convert this */
		timod_queue(fd, it);
	}
	SOLD("done");
}

static void timod_ok(unsigned int fd, int prim)
{
	struct T_primsg *it;
	struct T_ok_ack *ok;
	
	SOLD("creating ok ack");
	it = timod_mkctl(sizeof(*ok));
	if (it) {
		SOLD("got it");
		ok = (struct T_ok_ack *)&it->type;
		ok->PRIM_type = T_OK_ACK;
		ok->CORRECT_prim = prim;
		timod_queue(fd, it);
	}
	SOLD("done");
}

static int timod_optmgmt(unsigned int fd, int flag, char *opt_buf, int opt_len, int do_ret)
{
	int error, failed;
	int ret_space, ret_len;
	long args[5];
	char *ret_pos,*ret_buf;
	int (*sys_socketcall)(int, unsigned long *) =
		(int (*)(int, unsigned long *))SYS(socketcall);
	mm_segment_t old_fs = get_fs();

	SOLD("entry");
	SOLDD(("fd %u flg %u buf %p len %u doret %u",fd,flag,opt_buf,opt_len,do_ret));
	if (!do_ret && (!opt_buf || opt_len <= 0))
		return 0;
	SOLD("getting page");
	ret_pos = ret_buf = getpage();
	ret_space = BUF_SIZE;
	ret_len = 0;
	
	error = failed = 0;
	SOLD("looping");
	while(opt_len >= sizeof(struct opthdr)) {
		struct opthdr *opt;
		int orig_opt_len; 
		SOLD("loop start");
		opt = (struct opthdr *)ret_pos; 
		if (ret_space < sizeof(struct opthdr)) {
			failed = TSYSERR;
			break;
		}
		SOLD("getting opthdr");
		if (copy_from_user(opt, opt_buf, sizeof(struct opthdr)) ||
			opt->len > opt_len) {
			failed = TBADOPT;
			break;
		}
		SOLD("got opthdr");
		if (flag == T_NEGOTIATE) {
			char *buf;
			
			SOLD("handling T_NEGOTIATE");
			buf = ret_pos + sizeof(struct opthdr);
			if (ret_space < opt->len + sizeof(struct opthdr) ||
				copy_from_user(buf, opt_buf+sizeof(struct opthdr), opt->len)) {
				failed = TSYSERR;
				break;
			}
			SOLD("got optdata");
			args[0] = fd;
			args[1] = opt->level;
			args[2] = opt->name;
			args[3] = (long)buf;
			args[4] = opt->len;
			SOLD("calling SETSOCKOPT");
			set_fs(KERNEL_DS);
			error = sys_socketcall(SYS_SETSOCKOPT, args);
			set_fs(old_fs);
			if (error) {
				failed = TBADOPT;
				break;
			}
			SOLD("SETSOCKOPT ok");
		}
		orig_opt_len = opt->len;
		opt->len = ret_space - sizeof(struct opthdr);
		if (opt->len < 0) {
			failed = TSYSERR;
			break;
		}
		args[0] = fd;
		args[1] = opt->level;
		args[2] = opt->name;
		args[3] = (long)(ret_pos+sizeof(struct opthdr));
		args[4] = (long)&opt->len;
		SOLD("calling GETSOCKOPT");
		set_fs(KERNEL_DS);
		error = sys_socketcall(SYS_GETSOCKOPT, args);
		set_fs(old_fs);;
		if (error) {
			failed = TBADOPT;
			break;
		}
		SOLD("GETSOCKOPT ok");
		ret_space -= sizeof(struct opthdr) + opt->len;
		ret_len += sizeof(struct opthdr) + opt->len;
		ret_pos += sizeof(struct opthdr) + opt->len;
		opt_len -= sizeof(struct opthdr) + orig_opt_len;
		opt_buf += sizeof(struct opthdr) + orig_opt_len;
		SOLD("loop end");
	}
	SOLD("loop done");
	if (do_ret) {
		SOLD("generating ret msg");
		if (failed)
			timod_error(fd, T_OPTMGMT_REQ, failed, -error);
		else {
			struct T_primsg *it;
			it = timod_mkctl(sizeof(struct T_optmgmt_ack) + ret_len);
			if (it) {
				struct T_optmgmt_ack *ack =
					(struct T_optmgmt_ack *)&it->type;
				SOLD("got primsg");
				ack->PRIM_type = T_OPTMGMT_ACK;
				ack->OPT_length = ret_len;
				ack->OPT_offset = sizeof(struct T_optmgmt_ack);
				ack->MGMT_flags = (failed ? T_FAILURE : flag);
				memcpy(((char*)ack)+sizeof(struct T_optmgmt_ack),
					ret_buf, ret_len);
				timod_queue(fd, it);
			}
		}
	}
	SOLDD(("put_page %p\n", ret_buf));
	putpage(ret_buf);
	SOLD("done");	
	return 0;
}

int timod_putmsg(unsigned int fd, char *ctl_buf, int ctl_len,
			char *data_buf, int data_len, int flags)
{
	int ret, error, terror;
	char *buf;
	struct file *filp;
	struct inode *ino;
	struct sol_socket_struct *sock;
	mm_segment_t old_fs = get_fs();
	long args[6];
	int (*sys_socketcall)(int, unsigned long *) =
		(int (*)(int, unsigned long *))SYS(socketcall);
	int (*sys_sendto)(int, void *, size_t, unsigned, struct sockaddr *, int) =
		(int (*)(int, void *, size_t, unsigned, struct sockaddr *, int))SYS(sendto);
	filp = current->files->fd[fd];
	ino = filp->f_dentry->d_inode;
	sock = (struct sol_socket_struct *)filp->private_data;
	SOLD("entry");
	if (get_user(ret, (int *)A(ctl_buf)))
		return -EFAULT;
	switch (ret) {
	case T_BIND_REQ:
	{
		struct T_bind_req req;
		
		SOLDD(("bind %016lx(%016lx)\n", sock, filp));
		SOLD("T_BIND_REQ");
		if (sock->state != TS_UNBND) {
			timod_error(fd, T_BIND_REQ, TOUTSTATE, 0);
			return 0;
		}
		SOLD("state ok");
		if (copy_from_user(&req, ctl_buf, sizeof(req))) {
			timod_error(fd, T_BIND_REQ, TSYSERR, EFAULT);
			return 0;
		}
		SOLD("got ctl req");
		if (req.ADDR_offset && req.ADDR_length) {
			if (req.ADDR_length > BUF_SIZE) {
				timod_error(fd, T_BIND_REQ, TSYSERR, EFAULT);
				return 0;
			}
			SOLD("req size ok");
			buf = getpage();
			if (copy_from_user(buf, ctl_buf + req.ADDR_offset, req.ADDR_length)) {
				timod_error(fd, T_BIND_REQ, TSYSERR, EFAULT);
				putpage(buf);
				return 0;
			}
			SOLD("got ctl data");
			args[0] = fd;
			args[1] = (long)buf;
			args[2] = req.ADDR_length;
			SOLD("calling BIND");
			set_fs(KERNEL_DS);
			error = sys_socketcall(SYS_BIND, args);
			set_fs(old_fs);
			putpage(buf);
			SOLD("BIND returned");
		} else 
			error = 0;
		if (!error) {
			struct T_primsg *it;
			if (req.CONIND_number) {
	  			args[0] = fd;
  				args[1] = req.CONIND_number;
  				SOLD("calling LISTEN");
  				set_fs(KERNEL_DS);
	  			error = sys_socketcall(SYS_LISTEN, args);
  				set_fs(old_fs);
  				SOLD("LISTEN done");
  			}
			it = timod_mkctl(sizeof(struct T_bind_ack)+sizeof(struct sockaddr));
			if (it) {
				struct T_bind_ack *ack;

				ack = (struct T_bind_ack *)&it->type;
				ack->PRIM_type = T_BIND_ACK;
				ack->ADDR_offset = sizeof(*ack);
				ack->ADDR_length = sizeof(struct sockaddr);
				ack->CONIND_number = req.CONIND_number;
				args[0] = fd;
				args[1] = (long)(ack+sizeof(*ack));
				args[2] = (long)&ack->ADDR_length;
				set_fs(KERNEL_DS);
				sys_socketcall(SYS_GETSOCKNAME,args);
				set_fs(old_fs);
				sock->state = TS_IDLE;
				timod_ok(fd, T_BIND_REQ);
				timod_queue_end(fd, it);
				SOLD("BIND done");
				return 0;
			}
		}
		SOLD("some error");
		switch (error) {
			case -EINVAL:
				terror = TOUTSTATE;
				error = 0;
				break;
			case -EACCES:
				terror = TACCES;
				error = 0;
				break;
			case -EADDRNOTAVAIL:
			case -EADDRINUSE:
				terror = TNOADDR;
				error = 0;
				break;
			default:
				terror = TSYSERR;
				break;
		}
		timod_error(fd, T_BIND_REQ, terror, -error);
		SOLD("BIND done");
		return 0;
	}
	case T_CONN_REQ:
	{
		struct T_conn_req req;
		unsigned short oldflags;
		struct T_primsg *it;
		SOLD("T_CONN_REQ");
		if (sock->state != TS_UNBND && sock->state != TS_IDLE) {
			timod_error(fd, T_CONN_REQ, TOUTSTATE, 0);
			return 0;
		}
		SOLD("state ok");
		if (copy_from_user(&req, ctl_buf, sizeof(req))) {
			timod_error(fd, T_CONN_REQ, TSYSERR, EFAULT);
			return 0;
		}
		SOLD("got ctl req");
		if (ctl_len > BUF_SIZE) {
			timod_error(fd, T_CONN_REQ, TSYSERR, EFAULT);
			return 0;
		}
		SOLD("req size ok");