sys_ppc32.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

/*
 * sys_ppc32.c: Conversion between 32bit and 64bit native syscalls.
 *
 * Copyright (C) 2001 IBM
 * Copyright (C) 1997,1998 Jakub Jelinek ([e-mail])
 * Copyright (C) 1997 David S. Miller ([e-mail])
 *
 * These routines maintain argument size conversion between 32bit and 64bit
 * environment.
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <asm/ptrace.h>
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h> 
#include <linux/mm.h> 
#include <linux/file.h> 
#include <linux/signal.h>
#include <linux/utime.h>
#include <linux/resource.h>
#include <linux/times.h>
#include <linux/utsname.h>
#include <linux/timex.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/slab.h>
#include <linux/uio.h>
#include <linux/nfs_fs.h>
#include <linux/smb_fs.h>
#include <linux/smb_mount.h>
#include <linux/ncp_fs.h>
#include <linux/quota.h>
#include <linux/module.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/cache.h>
#include <linux/nfsd/xdr.h>
#include <linux/nfsd/syscall.h>
#include <linux/poll.h>
#include <linux/personality.h>
#include <linux/stat.h>
#include <linux/filter.h>
#include <linux/highmem.h>
#include <linux/highuid.h>
#include <linux/mman.h>
#include <linux/sysctl.h>

#include <asm/types.h>
#include <asm/ipc.h>
#include <asm/uaccess.h>

#include <asm/semaphore.h>

#include <net/scm.h>
#include <linux/elf.h>
#include <asm/ppcdebug.h>
#include <asm/time.h>
#include <asm/ppc32.h>

extern unsigned long wall_jiffies;
#define USEC_PER_SEC (1000000)

/* 
 * These are the flags in the MSR that the user is allowed to change
 * by modifying the saved value of the MSR on the stack.  SE and BE
 * should not be in this list since gdb may want to change these.  I.e,
 * you should be able to step out of a signal handler to see what
 * instruction executes next after the signal handler completes.
 * Alternately, if you stepped into a signal handler, you should be
 * able to continue 'til the next breakpoint from within the signal
 * handler, even if the handler returns.
 */
#define MSR_USERCHANGE	(MSR_FE0 | MSR_FE1)

extern asmlinkage long sys_utime(char * filename, struct utimbuf * times);

struct utimbuf32 {
	__kernel_time_t32 actime, modtime;
};

asmlinkage long sys32_utime(char * filename, struct utimbuf32 *times)
{
	struct utimbuf t;
	mm_segment_t old_fs;
	int ret;
	char *filenam;
	
	PPCDBG(PPCDBG_SYS32NI, "sys32_utime - running - filename=%s, times=%p - pid=%ld, comm=%s \n", filename, times, current->pid, current->comm);

	if (!times)
		return sys_utime(filename, NULL);
	if (get_user(t.actime, &times->actime) || __get_user(t.modtime, &times->modtime))
		return -EFAULT;
	filenam = getname(filename);

	ret = PTR_ERR(filenam);
	if (!IS_ERR(filenam)) {
		old_fs = get_fs();
		set_fs (KERNEL_DS); 
		ret = sys_utime(filenam, &t);
		set_fs (old_fs);
		putname (filenam);
	}

	return ret;
}



struct iovec32 { u32 iov_base; __kernel_size_t32 iov_len; };

typedef ssize_t (*IO_fn_t)(struct file *, char *, size_t, loff_t *);

static long do_readv_writev32(int type, struct file *file,
			      const struct iovec32 *vector, u32 count)
{
	unsigned long tot_len;
	struct iovec iovstack[UIO_FASTIOV];
	struct iovec *iov=iovstack, *ivp;
	struct inode *inode;
	long retval, i;
	IO_fn_t fn;

	/* First get the "struct iovec" from user memory and
	 * verify all the pointers
	 */
	if (!count)
		return 0;
	if(verify_area(VERIFY_READ, vector, sizeof(struct iovec32)*count))
		return -EFAULT;
	if (count > UIO_MAXIOV)
		return -EINVAL;
	if (count > UIO_FASTIOV) {
		iov = kmalloc(count*sizeof(struct iovec), GFP_KERNEL);
		if (!iov)
			return -ENOMEM;
	}

	tot_len = 0;
	i = count;
	ivp = iov;
	while(i > 0) {
		u32 len;
		u32 buf;

		__get_user(len, &vector->iov_len);
		__get_user(buf, &vector->iov_base);
		tot_len += len;
		ivp->iov_base = (void *)A(buf);
		ivp->iov_len = (__kernel_size_t) len;
		vector++;
		ivp++;
		i--;
	}

	inode = file->f_dentry->d_inode;
	/* VERIFY_WRITE actually means a read, as we write to user space */
	retval = locks_verify_area((type == VERIFY_WRITE
				    ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE),
				   inode, file, file->f_pos, tot_len);
	if (retval) {
		if (iov != iovstack)
			kfree(iov);
		return retval;
	}

	/* Then do the actual IO.  Note that sockets need to be handled
	 * specially as they have atomicity guarantees and can handle
	 * iovec's natively
	 */
	if (inode->i_sock) {
		int err;
		err = sock_readv_writev(type, inode, file, iov, count, tot_len);
		if (iov != iovstack)
			kfree(iov);
		return err;
	}

	if (!file->f_op) {
		if (iov != iovstack)
			kfree(iov);
		return -EINVAL;
	}
	/* VERIFY_WRITE actually means a read, as we write to user space */
	fn = file->f_op->read;
	if (type == VERIFY_READ)
		fn = (IO_fn_t) file->f_op->write;		
	ivp = iov;
	while (count > 0) {
		void * base;
		int len, nr;

		base = ivp->iov_base;
		len = ivp->iov_len;
		ivp++;
		count--;
		nr = fn(file, base, len, &file->f_pos);
		if (nr < 0) {
			if (retval)
				break;
			retval = nr;
			break;
		}
		retval += nr;
		if (nr != len)
			break;
	}
	if (iov != iovstack)
		kfree(iov);
	return retval;
}

asmlinkage long sys32_readv(u32 fd, struct iovec32 *vector, u32 count)
{
	struct file *file;
	long ret = -EBADF;
	
	PPCDBG(PPCDBG_SYS32, "sys32_readv - entered - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);

	file = fget(fd);
	if(!file)
		goto bad_file;

	if (file->f_op && (file->f_mode & FMODE_READ) &&
     (file->f_op->readv || file->f_op->read))
		ret = do_readv_writev32(VERIFY_WRITE, file, vector, count);
	fput(file);

bad_file:
	PPCDBG(PPCDBG_SYS32, "sys32_readv - exited - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
	return ret;
}

asmlinkage long sys32_writev(u32 fd, struct iovec32 *vector, u32 count)
{
	struct file *file;
	int ret = -EBADF;
	
	PPCDBG(PPCDBG_SYS32, "sys32_writev - entered - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);

	file = fget(fd);
	if(!file)
		goto bad_file;
	if (file->f_op && (file->f_mode & FMODE_WRITE) &&
	   (file->f_op->writev || file->f_op->write))
		ret = do_readv_writev32(VERIFY_READ, file, vector, count);
	fput(file);

bad_file:
	PPCDBG(PPCDBG_SYS32, "sys32_writev - exited - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
	return ret;
}



static inline int get_flock(struct flock *kfl, struct flock32 *ufl)
{
	int err;
	
	err = get_user(kfl->l_type, &ufl->l_type);
	err |= __get_user(kfl->l_whence, &ufl->l_whence);
	err |= __get_user(kfl->l_start, &ufl->l_start);
	err |= __get_user(kfl->l_len, &ufl->l_len);
	err |= __get_user(kfl->l_pid, &ufl->l_pid);
	return err;
}

static inline int put_flock(struct flock *kfl, struct flock32 *ufl)
{
	int err;
	
	err = __put_user(kfl->l_type, &ufl->l_type);
	err |= __put_user(kfl->l_whence, &ufl->l_whence);
	err |= __put_user(kfl->l_start, &ufl->l_start);
	err |= __put_user(kfl->l_len, &ufl->l_len);
	err |= __put_user(kfl->l_pid, &ufl->l_pid);
	return err;
}

extern asmlinkage long sys_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg);
asmlinkage long sys32_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg)
{
	switch (cmd) {
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
	{
		struct flock f;
		mm_segment_t old_fs;
		long ret;

		if(get_flock(&f, (struct flock32 *)arg))
			return -EFAULT;
		old_fs = get_fs(); set_fs (KERNEL_DS);
		ret = sys_fcntl(fd, cmd, (unsigned long)&f);
		set_fs (old_fs);
		if(put_flock(&f, (struct flock32 *)arg))
			return -EFAULT;
		return ret;
	}
	default:
		return sys_fcntl(fd, cmd, (unsigned long)arg);
	}
}

struct ncp_mount_data32 {
        int version;
        unsigned int ncp_fd;
        __kernel_uid_t32 mounted_uid;
        __kernel_pid_t32 wdog_pid;
        unsigned char mounted_vol[NCP_VOLNAME_LEN + 1];
        unsigned int time_out;
        unsigned int retry_count;
        unsigned int flags;
        __kernel_uid_t32 uid;
        __kernel_gid_t32 gid;
        __kernel_mode_t32 file_mode;
        __kernel_mode_t32 dir_mode;
};

static void *do_ncp_super_data_conv(void *raw_data)
{
	struct ncp_mount_data *n = (struct ncp_mount_data *)raw_data;
	struct ncp_mount_data32 *n32 = (struct ncp_mount_data32 *)raw_data;

	n->dir_mode = n32->dir_mode;
	n->file_mode = n32->file_mode;
	n->gid = n32->gid;
	n->uid = n32->uid;
	memmove (n->mounted_vol, n32->mounted_vol, (sizeof (n32->mounted_vol) + 3 * sizeof (unsigned int)));
	n->wdog_pid = n32->wdog_pid;
	n->mounted_uid = n32->mounted_uid;
	return raw_data;
}

struct smb_mount_data32 {
        int version;
        __kernel_uid_t32 mounted_uid;
        __kernel_uid_t32 uid;
        __kernel_gid_t32 gid;
        __kernel_mode_t32 file_mode;
        __kernel_mode_t32 dir_mode;
};

static void *do_smb_super_data_conv(void *raw_data)
{
	struct smb_mount_data *s = (struct smb_mount_data *)raw_data;
	struct smb_mount_data32 *s32 = (struct smb_mount_data32 *)raw_data;

	s->version = s32->version;
	s->mounted_uid = s32->mounted_uid;
	s->uid = s32->uid;
	s->gid = s32->gid;
	s->file_mode = s32->file_mode;
	s->dir_mode = s32->dir_mode;
	return raw_data;
}

static int copy_mount_stuff_to_kernel(const void *user, unsigned long *kernel)
{
	int i;
	unsigned long page;
	struct vm_area_struct *vma;

	*kernel = 0;
	if(!user)
		return 0;
	vma = find_vma(current->mm, (unsigned long)user);
	if(!vma || (unsigned long)user < vma->vm_start)
		return -EFAULT;
	if(!(vma->vm_flags & VM_READ))
		return -EFAULT;
	i = vma->vm_end - (unsigned long) user;
	if(PAGE_SIZE <= (unsigned long) i)
		i = PAGE_SIZE - 1;
	if(!(page = __get_free_page(GFP_KERNEL)))
		return -ENOMEM;
	if(copy_from_user((void *) page, user, i)) {
		free_page(page);
		return -EFAULT;
	}
	*kernel = page;
	return 0;
}

#define SMBFS_NAME	"smbfs"
#define NCPFS_NAME	"ncpfs"

asmlinkage long sys32_mount(char *dev_name, char *dir_name, char *type, unsigned long new_flags, u32 data)
{
	unsigned long type_page = 0;
	unsigned long data_page = 0;
	unsigned long dev_page = 0;
	unsigned long dir_page = 0;
	int err, is_smb, is_ncp;
	
	PPCDBG(PPCDBG_SYS32, "sys32_mount - entered - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);

	is_smb = is_ncp = 0;

	err = copy_mount_stuff_to_kernel((const void *)type, &type_page);
	if (err)
		goto out;

	if (!type_page) {
		err = -EINVAL;
		goto out;
	}

	is_smb = !strcmp((char *)type_page, SMBFS_NAME);
	is_ncp = !strcmp((char *)type_page, NCPFS_NAME);

	err = copy_mount_stuff_to_kernel((const void *)AA(data), &data_page);
	if (err)
		goto type_out;

	err = copy_mount_stuff_to_kernel(dev_name, &dev_page);
	if (err)
		goto data_out;

	err = copy_mount_stuff_to_kernel(dir_name, &dir_page);
	if (err)
		goto dev_out;

	if (!is_smb && !is_ncp) {
		lock_kernel();
		err = do_mount((char*)dev_page, (char*)dir_page,
				(char*)type_page, new_flags, (char*)data_page);
		unlock_kernel();
	} else {
		if (is_ncp)
			do_ncp_super_data_conv((void *)data_page);
		else
			do_smb_super_data_conv((void *)data_page);

		lock_kernel();
		err = do_mount((char*)dev_page, (char*)dir_page,
				(char*)type_page, new_flags, (char*)data_page);
		unlock_kernel();
	}
	free_page(dir_page);

dev_out:
	free_page(dev_page);

data_out:
	free_page(data_page);

type_out:
	free_page(type_page);

out:
	
	PPCDBG(PPCDBG_SYS32, "sys32_mount - exited - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);

	return err;
}

struct dqblk32 {
    __u32 dqb_bhardlimit;
    __u32 dqb_bsoftlimit;
    __u32 dqb_curblocks;
    __u32 dqb_ihardlimit;
    __u32 dqb_isoftlimit;
    __u32 dqb_curinodes;
    __kernel_time_t32 dqb_btime;
    __kernel_time_t32 dqb_itime;
};
                                

extern asmlinkage long sys_quotactl(int cmd, const char *special, int id, caddr_t addr);

/* Note: it is necessary to treat cmd and id as unsigned ints, 
 * with the corresponding cast to a signed int to insure that the 
 * proper conversion (sign extension) between the register representation of a signed int (msr in 32-bit mode)
 * and the register representation of a signed int (msr in 64-bit mode) is performed.
 */
asmlinkage long sys32_quotactl(u32 cmd_parm, const char *special, u32 id_parm, unsigned long addr)
{
  int cmd = (int)cmd_parm;
  int id  = (int)id_parm;
	int cmds = cmd >> SUBCMDSHIFT;
	int err;
	struct dqblk d;
	mm_segment_t old_fs;
	char *spec;
	
	PPCDBG(PPCDBG_SYS32, "sys32_quotactl - entered - pid=%ld current=%lx comm=%s \n",
		    current->pid, current, current->comm);

	switch (cmds) {
	case Q_GETQUOTA:
		break;
	case Q_SETQUOTA:
	case Q_SETUSE:
	case Q_SETQLIM: