osf_sys.c

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/*
 *  linux/arch/alpha/kernel/osf_sys.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 */

/*
 * This file handles some of the stranger OSF/1 system call interfaces.
 * Some of the system calls expect a non-C calling standard, others have
 * special parameter blocks..
 */

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/malloc.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/utsname.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/major.h>
#include <linux/stat.h>
#include <linux/mman.h>
#include <linux/shm.h>
#include <linux/poll.h>
#include <linux/file.h>
#include <linux/types.h>
#include <linux/ipc.h>

#include <asm/fpu.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/sysinfo.h>
#include <asm/hwrpb.h>
#include <asm/processor.h>

extern int do_pipe(int *);

extern asmlinkage int sys_swapon(const char *specialfile, int swap_flags);
extern asmlinkage unsigned long sys_brk(unsigned long);

/*
 * Brk needs to return an error.  Still support Linux's brk(0) query idiom,
 * which OSF programs just shouldn't be doing.  We're still not quite
 * identical to OSF as we don't return 0 on success, but doing otherwise
 * would require changes to libc.  Hopefully this is good enough.
 */
asmlinkage unsigned long osf_brk(unsigned long brk)
{
	unsigned long retval = sys_brk(brk);
	if (brk && brk != retval)
		retval = -ENOMEM;
	return retval;
}
 
/*
 * This is pure guess-work..
 */
asmlinkage int osf_set_program_attributes(
	unsigned long text_start, unsigned long text_len,
	unsigned long bss_start, unsigned long bss_len)
{
	struct mm_struct *mm;

	lock_kernel();
	mm = current->mm;
	mm->end_code = bss_start + bss_len;
	mm->brk = bss_start + bss_len;
	printk("set_program_attributes(%lx %lx %lx %lx)\n",
		text_start, text_len, bss_start, bss_len);
	unlock_kernel();
	return 0;
}

/*
 * OSF/1 directory handling functions...
 *
 * The "getdents()" interface is much more sane: the "basep" stuff is
 * braindamage (it can't really handle filesystems where the directory
 * offset differences aren't the same as "d_reclen").
 */
#define NAME_OFFSET(de) ((int) ((de)->d_name - (char *) (de)))
#define ROUND_UP(x) (((x)+3) & ~3)

struct osf_dirent {
	unsigned int d_ino;
	unsigned short d_reclen;
	unsigned short d_namlen;
	char d_name[1];
};

struct osf_dirent_callback {
	struct osf_dirent *dirent;
	long *basep;
	int count;
	int error;
};

static int osf_filldir(void *__buf, const char *name, int namlen, off_t offset,
		       ino_t ino, unsigned int d_type)
{
	struct osf_dirent *dirent;
	struct osf_dirent_callback *buf = (struct osf_dirent_callback *) __buf;
	int reclen = ROUND_UP(NAME_OFFSET(dirent) + namlen + 1);

	buf->error = -EINVAL;	/* only used if we fail */
	if (reclen > buf->count)
		return -EINVAL;
	if (buf->basep) {
		put_user(offset, buf->basep);
		buf->basep = NULL;
	}
	dirent = buf->dirent;
	put_user(ino, &dirent->d_ino);
	put_user(namlen, &dirent->d_namlen);
	put_user(reclen, &dirent->d_reclen);
	copy_to_user(dirent->d_name, name, namlen);
	put_user(0, dirent->d_name + namlen);
	((char *) dirent) += reclen;
	buf->dirent = dirent;
	buf->count -= reclen;
	return 0;
}

asmlinkage int osf_getdirentries(unsigned int fd, struct osf_dirent *dirent,
				 unsigned int count, long *basep)
{
	int error;
	struct file *file;
	struct osf_dirent_callback buf;

	error = -EBADF;
	file = fget(fd);
	if (!file)
		goto out;

	buf.dirent = dirent;
	buf.basep = basep;
	buf.count = count;
	buf.error = 0;

	error = vfs_readdir(file, osf_filldir, &buf);
	if (error < 0)
		goto out_putf;

	error = buf.error;
	if (count != buf.count)
		error = count - buf.count;

out_putf:
	fput(file);
out:
	return error;
}

#undef ROUND_UP
#undef NAME_OFFSET

/*
 * Alpha syscall convention has no problem returning negative
 * values:
 */
asmlinkage int osf_getpriority(int which, int who, int a2, int a3, int a4,
			       int a5, struct pt_regs regs)
{
	extern int sys_getpriority(int, int);
	int prio;

	/*
	 * We don't need to acquire the kernel lock here, because
	 * all of these operations are local. sys_getpriority
	 * will get the lock as required..
	 */
	prio = sys_getpriority(which, who);
	if (prio >= 0) {
		regs.r0 = 0;		/* special return: no errors */
		prio = 20 - prio;
	}
	return prio;
}

/*
 * No need to acquire the kernel lock, we're local..
 */
asmlinkage unsigned long sys_getxuid(int a0, int a1, int a2, int a3, int a4,
				     int a5, struct pt_regs regs)
{
	struct task_struct * tsk = current;
	(&regs)->r20 = tsk->euid;
	return tsk->uid;
}

asmlinkage unsigned long sys_getxgid(int a0, int a1, int a2, int a3, int a4,
				     int a5, struct pt_regs regs)
{
	struct task_struct * tsk = current;
	(&regs)->r20 = tsk->egid;
	return tsk->gid;
}

asmlinkage unsigned long sys_getxpid(int a0, int a1, int a2, int a3, int a4,
				     int a5, struct pt_regs regs)
{
	struct task_struct *tsk = current;

	/* 
	 * This isn't strictly "local" any more and we should actually
	 * acquire the kernel lock. The "p_opptr" pointer might change
	 * if the parent goes away (or due to ptrace). But any race
	 * isn't actually going to matter, as if the parent happens
	 * to change we can happily return either of the pids.
	 */
	(&regs)->r20 = tsk->p_opptr->pid;
	return tsk->pid;
}

asmlinkage unsigned long osf_mmap(unsigned long addr, unsigned long len,
	       unsigned long prot, unsigned long flags, unsigned long fd,
				  unsigned long off)
{
	struct file *file = NULL;
	unsigned long ret = -EBADF;

#if 0
	if (flags & (_MAP_HASSEMAPHORE | _MAP_INHERIT | _MAP_UNALIGNED))
		printk("%s: unimplemented OSF mmap flags %04lx\n", 
			current->comm, flags);
#endif
	if (!(flags & MAP_ANONYMOUS)) {
		file = fget(fd);
		if (!file)
			goto out;
	}
	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
	down(&current->mm->mmap_sem);
	ret = do_mmap(file, addr, len, prot, flags, off);
	up(&current->mm->mmap_sem);
	if (file)
		fput(file);
out:
	return ret;
}


/*
 * The OSF/1 statfs structure is much larger, but this should
 * match the beginning, at least.
 */
struct osf_statfs {
	short f_type;
	short f_flags;
	int f_fsize;
	int f_bsize;
	int f_blocks;
	int f_bfree;
	int f_bavail;
	int f_files;
	int f_ffree;
	__kernel_fsid_t f_fsid;
} *osf_stat;

static int linux_to_osf_statfs(struct statfs *linux_stat, struct osf_statfs *osf_stat, unsigned long bufsiz)
{
	struct osf_statfs tmp_stat;

	tmp_stat.f_type = linux_stat->f_type;
	tmp_stat.f_flags = 0;	/* mount flags */
	/* Linux doesn't provide a "fundamental filesystem block size": */
	tmp_stat.f_fsize = linux_stat->f_bsize;
	tmp_stat.f_bsize = linux_stat->f_bsize;
	tmp_stat.f_blocks = linux_stat->f_blocks;
	tmp_stat.f_bfree = linux_stat->f_bfree;
	tmp_stat.f_bavail = linux_stat->f_bavail;
	tmp_stat.f_files = linux_stat->f_files;
	tmp_stat.f_ffree = linux_stat->f_ffree;
	tmp_stat.f_fsid = linux_stat->f_fsid;
	if (bufsiz > sizeof(tmp_stat))
		bufsiz = sizeof(tmp_stat);
	return copy_to_user(osf_stat, &tmp_stat, bufsiz) ? -EFAULT : 0;
}

static int do_osf_statfs(struct dentry * dentry, struct osf_statfs *buffer, unsigned long bufsiz)
{
	struct statfs linux_stat;
	int error = vfs_statfs(dentry->d_inode->i_sb, &linux_stat);
	if (!error)
		error = linux_to_osf_statfs(&linux_stat, buffer, bufsiz);
	return error;	
}

asmlinkage int osf_statfs(char *path, struct osf_statfs *buffer, unsigned long bufsiz)
{
	struct nameidata nd;
	int retval;

	retval = user_path_walk(path, &nd);
	if (!retval) {
		retval = do_osf_statfs(nd.dentry, buffer, bufsiz);
		path_release(&nd);
	}
	return retval;
}

asmlinkage int osf_fstatfs(unsigned long fd, struct osf_statfs *buffer, unsigned long bufsiz)
{
	struct file *file;
	int retval;

	retval = -EBADF;
	file = fget(fd);
	if (file) {
		retval = do_osf_statfs(file->f_dentry, buffer, bufsiz);
		fput(file);
	}
	return retval;
}

/*
 * Uhh.. OSF/1 mount parameters aren't exactly obvious..
 *
 * Although to be frank, neither are the native Linux/i386 ones..
 */
struct ufs_args {
	char *devname;
	int flags;
	uid_t exroot;
};

struct cdfs_args {
	char *devname;
	int flags;
	uid_t exroot;
/*
 * This has lots more here, which Linux handles with the option block
 * but I'm too lazy to do the translation into ASCII.
 */
};

struct procfs_args {
	char *devname;
	int flags;
	uid_t exroot;
};

/*
 * We can't actually handle ufs yet, so we translate UFS mounts to
 * ext2fs mounts. I wouldn't mind a UFS filesystem, but the UFS
 * layout is so braindead it's a major headache doing it.
 *
 * Just how long ago was it written? OTOH our UFS driver may be still
 * unhappy with OSF UFS. [CHECKME]
 */
static int osf_ufs_mount(char *dirname, struct ufs_args *args, int flags)
{
	int retval;
	struct cdfs_args tmp;
	char *devname;

	retval = -EFAULT;
	if (copy_from_user(&tmp, args, sizeof(tmp)))
		goto out;
	devname = getname(tmp.devname);
	retval = PTR_ERR(devname);
	if (IS_ERR(devname))
		goto out;
	retval = do_mount(devname, dirname, "ext2", flags, NULL);
	putname(devname);
out:
	return retval;
}

static int osf_cdfs_mount(char *dirname, struct cdfs_args *args, int flags)
{
	int retval;
	struct cdfs_args tmp;
	char *devname;

	retval = -EFAULT;
	if (copy_from_user(&tmp, args, sizeof(tmp)))
		goto out;
	devname = getname(tmp.devname);
	retval = PTR_ERR(devname);
	if (IS_ERR(devname))
		goto out;
	retval = do_mount(devname, dirname, "iso9660", flags, NULL);
	putname(devname);
out:
	return retval;
}

static int osf_procfs_mount(char *dirname, struct procfs_args *args, int flags)
{
	struct procfs_args tmp;

	if (copy_from_user(&tmp, args, sizeof(tmp)))
		return -EFAULT;

	return do_mount("", dirname, "proc", flags, NULL);
}

asmlinkage int osf_mount(unsigned long typenr, char *path, int flag, void *data)
{
	int retval = -EINVAL;
	char *name;

	lock_kernel();

	name = getname(path);
	retval = PTR_ERR(name);
	if (IS_ERR(name))
		goto out;
	switch (typenr) {
	case 1:
		retval = osf_ufs_mount(name, (struct ufs_args *) data, flag);
		break;
	case 6:
		retval = osf_cdfs_mount(name, (struct cdfs_args *) data, flag);
		break;
	case 9:
		retval = osf_procfs_mount(name, (struct procfs_args *) data, flag);
		break;
	default:
		printk("osf_mount(%ld, %x)\n", typenr, flag);
	}
	putname(name);
out:
	unlock_kernel();
	return retval;
}

asmlinkage int osf_utsname(char *name)
{
	int error;