sys_sunos.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

/* $Id: sys_sunos.c,v 1.135 2001/08/13 14:40:10 davem Exp $
 * sys_sunos.c: SunOS specific syscall compatibility support.
 *
 * Copyright (C) 1995 David S. Miller ([e-mail])
 * Copyright (C) 1995 Miguel de Icaza ([e-mail])
 *
 * Based upon preliminary work which is:
 *
 * Copyright (C) 1995 Adrian M. Rodriguez ([e-mail])
 *
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/resource.h>
#include <linux/ipc.h>
#include <linux/shm.h>
#include <linux/msg.h>
#include <linux/sem.h>
#include <linux/signal.h>
#include <linux/uio.h>
#include <linux/utsname.h>
#include <linux/major.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>

#include <asm/uaccess.h>
#ifndef KERNEL_DS
#include <linux/segment.h>
#endif

#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/pconf.h>
#include <asm/idprom.h> /* for gethostid() */
#include <asm/unistd.h>
#include <asm/system.h>

/* For the nfs mount emulation */
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/nfs.h>
#include <linux/nfs2.h>
#include <linux/nfs_mount.h>

/* for sunos_select */
#include <linux/time.h>
#include <linux/personality.h>

/* NR_OPEN is now larger and dynamic in recent kernels. */
#define SUNOS_NR_OPEN	256

/* We use the SunOS mmap() semantics. */
asmlinkage unsigned long sunos_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 retval, ret_type;

	if(flags & MAP_NORESERVE) {
		static int cnt;
		if (cnt++ < 10)
			printk("%s: unimplemented SunOS MAP_NORESERVE mmap() flag\n",
			       current->comm);
		flags &= ~MAP_NORESERVE;
	}
	retval = -EBADF;
	if(!(flags & MAP_ANONYMOUS)) {
		if (fd >= SUNOS_NR_OPEN)
			goto out;
		file = fget(fd);
		if (!file)
			goto out;
	}

	retval = -EINVAL;
	/* If this is ld.so or a shared library doing an mmap
	 * of /dev/zero, transform it into an anonymous mapping.
	 * SunOS is so stupid some times... hmph!
	 */
	if (file) {
		if(MAJOR(file->f_dentry->d_inode->i_rdev) == MEM_MAJOR &&
		   MINOR(file->f_dentry->d_inode->i_rdev) == 5) {
			flags |= MAP_ANONYMOUS;
			fput(file);
			file = 0;
		}
	}
	ret_type = flags & _MAP_NEW;
	flags &= ~_MAP_NEW;

	if(!(flags & MAP_FIXED))
		addr = 0;
	else {
		if (ARCH_SUN4C_SUN4 &&
		    (len > 0x20000000 ||
		     ((flags & MAP_FIXED) &&
		      addr < 0xe0000000 && addr + len > 0x20000000)))
			goto out_putf;

		/* See asm-sparc/uaccess.h */
		if (len > TASK_SIZE - PAGE_SIZE ||
		    addr + len > TASK_SIZE - PAGE_SIZE)
			goto out_putf;
	}

	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
	down_write(&current->mm->mmap_sem);
	retval = do_mmap(file, addr, len, prot, flags, off);
	up_write(&current->mm->mmap_sem);
	if(!ret_type)
		retval = ((retval < PAGE_OFFSET) ? 0 : retval);

out_putf:
	if (file)
		fput(file);
out:
	return retval;
}

/* lmbench calls this, just say "yeah, ok" */
asmlinkage int sunos_mctl(unsigned long addr, unsigned long len, int function, char *arg)
{
	return 0;
}

/* SunOS is completely broken... it returns 0 on success, otherwise
 * ENOMEM.  For sys_sbrk() it wants the old brk value as a return
 * on success and ENOMEM as before on failure.
 */
asmlinkage int sunos_brk(unsigned long brk)
{
	int freepages, retval = -ENOMEM;
	unsigned long rlim;
	unsigned long newbrk, oldbrk;

	down_write(&current->mm->mmap_sem);
	if(ARCH_SUN4C_SUN4) {
		if(brk >= 0x20000000 && brk < 0xe0000000) {
			goto out;
		}
	}

	if (brk < current->mm->end_code)
		goto out;

	newbrk = PAGE_ALIGN(brk);
	oldbrk = PAGE_ALIGN(current->mm->brk);
	retval = 0;
	if (oldbrk == newbrk) {
		current->mm->brk = brk;
		goto out;
	}

	/*
	 * Always allow shrinking brk
	 */
	if (brk <= current->mm->brk) {
		current->mm->brk = brk;
		do_munmap(current->mm, newbrk, oldbrk-newbrk);
		goto out;
	}
	/*
	 * Check against rlimit and stack..
	 */
	retval = -ENOMEM;
	rlim = current->rlim[RLIMIT_DATA].rlim_cur;
	if (rlim >= RLIM_INFINITY)
		rlim = ~0;
	if (brk - current->mm->end_code > rlim)
		goto out;

	/*
	 * Check against existing mmap mappings.
	 */
	if (find_vma_intersection(current->mm, oldbrk, newbrk+PAGE_SIZE))
		goto out;

	/*
	 * stupid algorithm to decide if we have enough memory: while
	 * simple, it hopefully works in most obvious cases.. Easy to
	 * fool it, but this should catch most mistakes.
	 */
	freepages = atomic_read(&buffermem_pages) >> PAGE_SHIFT;
	freepages += atomic_read(&page_cache_size);
	freepages >>= 1;
	freepages += nr_free_pages();
	freepages += nr_swap_pages;
	freepages -= num_physpages >> 4;
	freepages -= (newbrk-oldbrk) >> PAGE_SHIFT;
	if (freepages < 0)
		goto out;
	/*
	 * Ok, we have probably got enough memory - let it rip.
	 */
	current->mm->brk = brk;
	do_brk(oldbrk, newbrk-oldbrk);
	retval = 0;
out:
	up_write(&current->mm->mmap_sem);
	return retval;
}

asmlinkage unsigned long sunos_sbrk(int increment)
{
	int error;
	unsigned long oldbrk;

	/* This should do it hopefully... */
	lock_kernel();
	oldbrk = current->mm->brk;
	error = sunos_brk(((int) current->mm->brk) + increment);
	if(!error)
		error = oldbrk;
	unlock_kernel();
	return error;
}

/* XXX Completely undocumented, and completely magic...
 * XXX I believe it is to increase the size of the stack by
 * XXX argument 'increment' and return the new end of stack
 * XXX area.  Wheee...
 */
asmlinkage unsigned long sunos_sstk(int increment)
{
	lock_kernel();
	printk("%s: Call to sunos_sstk(increment<%d>) is unsupported\n",
	       current->comm, increment);
	unlock_kernel();
	return -1;
}

/* Give hints to the kernel as to what paging strategy to use...
 * Completely bogus, don't remind me.
 */
#define VA_NORMAL     0 /* Normal vm usage expected */
#define VA_ABNORMAL   1 /* Abnormal/random vm usage probable */
#define VA_SEQUENTIAL 2 /* Accesses will be of a sequential nature */
#define VA_INVALIDATE 3 /* Page table entries should be flushed ??? */
static char *vstrings[] = {
	"VA_NORMAL",
	"VA_ABNORMAL",
	"VA_SEQUENTIAL",
	"VA_INVALIDATE",
};

asmlinkage void sunos_vadvise(unsigned long strategy)
{
	/* I wanna see who uses this... */
	lock_kernel();
	printk("%s: Advises us to use %s paging strategy\n",
	       current->comm,
	       strategy <= 3 ? vstrings[strategy] : "BOGUS");
	unlock_kernel();
}

/* This just wants the soft limit (ie. rlim_cur element) of the RLIMIT_NOFILE
 * resource limit and is for backwards compatibility with older sunos
 * revs.
 */
asmlinkage long sunos_getdtablesize(void)
{
	return SUNOS_NR_OPEN;
}

#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

asmlinkage unsigned long sunos_sigblock(unsigned long blk_mask)
{
	unsigned long old;

	spin_lock_irq(&current->sigmask_lock);
	old = current->blocked.sig[0];
	current->blocked.sig[0] |= (blk_mask & _BLOCKABLE);
	recalc_sigpending(current);
	spin_unlock_irq(&current->sigmask_lock);
	return old;
}

asmlinkage unsigned long sunos_sigsetmask(unsigned long newmask)
{
	unsigned long retval;

	spin_lock_irq(&current->sigmask_lock);
	retval = current->blocked.sig[0];
	current->blocked.sig[0] = (newmask & _BLOCKABLE);
	recalc_sigpending(current);
	spin_unlock_irq(&current->sigmask_lock);
	return retval;
}

/* SunOS getdents is very similar to the newer Linux (iBCS2 compliant)    */
/* getdents system call, the format of the structure just has a different */
/* layout (d_off+d_ino instead of d_ino+d_off) */
struct sunos_dirent {
    long           d_off;
    unsigned long  d_ino;
    unsigned short d_reclen;
    unsigned short d_namlen;
    char           d_name[1];
};

struct sunos_dirent_callback {
    struct sunos_dirent *curr;
    struct sunos_dirent *previous;
    int count;
    int error;
};

#define NAME_OFFSET(de) ((int) ((de)->d_name - (char *) (de)))
#define ROUND_UP(x) (((x)+sizeof(long)-1) & ~(sizeof(long)-1))

static int sunos_filldir(void * __buf, const char * name, int namlen,
			 loff_t offset, ino_t ino, unsigned int d_type)
{
	struct sunos_dirent * dirent;
	struct sunos_dirent_callback * buf = (struct sunos_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;
	dirent = buf->previous;
	if (dirent)
		put_user(offset, &dirent->d_off);
	dirent = buf->curr;
	buf->previous = 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->curr = dirent;
	buf->count -= reclen;
	return 0;
}

asmlinkage int sunos_getdents(unsigned int fd, void * dirent, int cnt)
{
	struct file * file;
	struct sunos_dirent * lastdirent;
	struct sunos_dirent_callback buf;
	int error = -EBADF;

	if (fd >= SUNOS_NR_OPEN)
		goto out;

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

	error = -EINVAL;
	if (cnt < (sizeof(struct sunos_dirent) + 255))
		goto out_putf;

	buf.curr = (struct sunos_dirent *) dirent;
	buf.previous = NULL;
	buf.count = cnt;
	buf.error = 0;

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

	lastdirent = buf.previous;
	error = buf.error;
	if (lastdirent) {
		put_user(file->f_pos, &lastdirent->d_off);
		error = cnt - buf.count;
	}

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

/* Old sunos getdirentries, severely broken compatibility stuff here. */
struct sunos_direntry {
    unsigned long  d_ino;
    unsigned short d_reclen;
    unsigned short d_namlen;
    char           d_name[1];
};

struct sunos_direntry_callback {
    struct sunos_direntry *curr;
    struct sunos_direntry *previous;
    int count;
    int error;
};

static int sunos_filldirentry(void * __buf, const char * name, int namlen,
			      loff_t offset, ino_t ino, unsigned int d_type)
{
	struct sunos_direntry * dirent;
	struct sunos_direntry_callback * buf = (struct sunos_direntry_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;
	dirent = buf->previous;
	dirent = buf->curr;
	buf->previous = 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->curr = dirent;
	buf->count -= reclen;
	return 0;
}

asmlinkage int sunos_getdirentries(unsigned int fd, void * dirent, int cnt, unsigned int *basep)
{
	struct file * file;
	struct sunos_direntry * lastdirent;
	struct sunos_direntry_callback buf;
	int error = -EBADF;

	if (fd >= SUNOS_NR_OPEN)
		goto out;

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

	error = -EINVAL;
	if(cnt < (sizeof(struct sunos_direntry) + 255))
		goto out_putf;

	buf.curr = (struct sunos_direntry *) dirent;
	buf.previous = NULL;
	buf.count = cnt;
	buf.error = 0;

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

	lastdirent = buf.previous;
	error = buf.error;
	if (lastdirent) {
		put_user(file->f_pos, basep);
		error = cnt - buf.count;
	}

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

struct sunos_utsname {
	char sname[9];
	char nname[9];
	char nnext[56];
	char rel[9];
	char ver[9];
	char mach[9];
};

asmlinkage int sunos_uname(struct sunos_utsname *name)
{
	int ret;
	down_read(&uts_sem);
	ret = copy_to_user(&name->sname[0], &system_utsname.sysname[0], sizeof(name->sname) - 1);
	if (!ret) {
		ret |= __copy_to_user(&name->nname[0], &system_utsname.nodename[0], sizeof(name->nname) - 1);
		ret |= __put_user('\0', &name->nname[8]);
		ret |= __copy_to_user(&name->rel[0], &system_utsname.release[0], sizeof(name->rel) - 1);
		ret |= __copy_to_user(&name->ver[0], &system_utsname.version[0], sizeof(name->ver) - 1);
		ret |= __copy_to_user(&name->mach[0], &system_utsname.machine[0], sizeof(name->mach) - 1);
	}
	up_read(&uts_sem);
	return ret;
}

asmlinkage int sunos_nosys(void)
{
	struct pt_regs *regs;
	siginfo_t info;
	static int cnt;

	lock_kernel();
	regs = current->thread.kregs;
	info.si_signo = SIGSYS;
	info.si_errno = 0;
	info.si_code = __SI_FAULT|0x100;
	info.si_addr = (void *)regs->pc;
	info.si_trapno = regs->u_regs[UREG_G1];
	send_sig_info(SIGSYS, &info, current);
	if (cnt++ < 4) {
		printk("Process makes ni_syscall number %d, register dump:\n",
		       (int) regs->u_regs[UREG_G1]);
		show_regs(regs);
	}
	unlock_kernel();
	return -ENOSYS;
}

/* This is not a real and complete implementation yet, just to keep
 * the easy SunOS binaries happy.
 */
asmlinkage int sunos_fpathconf(int fd, int name)
{
	int ret;

	switch(name) {
	case _PCONF_LINK:
		ret = LINK_MAX;
		break;
	case _PCONF_CANON:
		ret = MAX_CANON;
		break;
	case _PCONF_INPUT:
		ret = MAX_INPUT;
		break;
	case _PCONF_NAME:
		ret = NAME_MAX;
		break;
	case _PCONF_PATH:
		ret = PATH_MAX;
		break;
	case _PCONF_PIPE:
		ret = PIPE_BUF;
		break;
	case _PCONF_CHRESTRICT:		/* XXX Investigate XXX */
		ret = 1;
		break;
	case _PCONF_NOTRUNC:		/* XXX Investigate XXX */
	case _PCONF_VDISABLE:
		ret = 0;
		break;
	default:
		ret = -EINVAL;
		break;
	}
	return ret;
}

asmlinkage int sunos_pathconf(char *path, int name)
{
	int ret;

	ret = sunos_fpathconf(0, name); /* XXX cheese XXX */
	return ret;
}

/* SunOS mount system call emulation */
extern asmlinkage int
sys_select(int n, fd_set *inp, fd_set *outp, fd_set *exp, struct timeval *tvp);

asmlinkage int sunos_select(int width, fd_set *inp, fd_set *outp, fd_set *exp, struct timeval *tvp)
{
	int ret;

	/* SunOS binaries expect that select won't change the tvp contents */
	ret = sys_select (width, inp, outp, exp, tvp);
	if (ret == -EINTR && tvp) {
		time_t sec, usec;

		__get_user(sec, &tvp->tv_sec);
		__get_user(usec, &tvp->tv_usec);

		if (sec == 0 && usec == 0)
			ret = 0;
	}
	return ret;
}

asmlinkage void sunos_nop(void)
{
	return;
}

/* SunOS mount/umount. */
#define SMNT_RDONLY       1
#define SMNT_NOSUID       2
#define SMNT_NEWTYPE      4
#define SMNT_GRPID        8
#define SMNT_REMOUNT      16
#define SMNT_NOSUB        32
#define SMNT_MULTI        64
#define SMNT_SYS5         128

struct sunos_fh_t {
	char fh_data [NFS_FHSIZE];
};

struct sunos_nfs_mount_args {
	struct sockaddr_in  *addr; /* file server address */
	struct nfs_fh *fh;     /* File handle to be mounted */
	int        flags;      /* flags */
	int        wsize;      /* write size in bytes */