sys_ia64.c

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/*
 * This file contains various system calls that have different calling
 * conventions on different platforms.
 *
 * Copyright (C) 1999-2000 Hewlett-Packard Co
 * Copyright (C) 1999-2000 David Mosberger-Tang <[e-mail]>
 */
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/sched.h>
#include <linux/file.h>		/* doh, must come after sched.h... */
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/highuid.h>

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

#define COLOR_ALIGN(addr)	(((addr) + SHMLBA - 1) & ~(SHMLBA - 1))

unsigned long
get_unmapped_area (unsigned long addr, unsigned long len)
{
	struct vm_area_struct * vmm;

	if (len > RGN_MAP_LIMIT)
		return 0;
	if (!addr)
		addr = TASK_UNMAPPED_BASE;

	if (current->thread.flags & IA64_THREAD_MAP_SHARED)
		addr = COLOR_ALIGN(addr);
	else
		addr = PAGE_ALIGN(addr);

	for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
		/* At this point:  (!vmm || addr < vmm->vm_end). */
		if (TASK_SIZE - len < addr)
			return 0;
		if (rgn_offset(addr) + len > RGN_MAP_LIMIT)	/* no risk of overflow here... */
			return 0;
		if (!vmm || addr + len <= vmm->vm_start)
			return addr;
		addr = vmm->vm_end;
	}
}

asmlinkage long
ia64_getpriority (int which, int who, long arg2, long arg3, long arg4, long arg5, long arg6, 
		  long arg7, long stack)
{
	struct pt_regs *regs = (struct pt_regs *) &stack;
	extern long sys_getpriority (int, int);
	long prio;

	prio = sys_getpriority(which, who);
	if (prio >= 0) {
		regs->r8 = 0;	/* ensure negative priority is not mistaken as error code */
		prio = 20 - prio;
	}
	return prio;
}

/* XXX obsolete, but leave it here until the old libc is gone... */
asmlinkage unsigned long
sys_getpagesize (void)
{
	return PAGE_SIZE;
}

asmlinkage unsigned long
ia64_shmat (int shmid, void *shmaddr, int shmflg, long arg3, long arg4, long arg5, long arg6,
	    long arg7, long stack)
{
	extern int sys_shmat (int shmid, char *shmaddr, int shmflg, ulong *raddr);
	struct pt_regs *regs = (struct pt_regs *) &stack;
	unsigned long raddr;
	int retval;

	retval = sys_shmat(shmid, shmaddr, shmflg, &raddr);
	if (retval < 0)
		return retval;

	regs->r8 = 0;	/* ensure negative addresses are not mistaken as an error code */
	return raddr;
}

asmlinkage unsigned long
ia64_brk (unsigned long brk, long arg1, long arg2, long arg3,
	  long arg4, long arg5, long arg6, long arg7, long stack)
{
	extern int vm_enough_memory (long pages);
	struct pt_regs *regs = (struct pt_regs *) &stack;
	unsigned long rlim, retval, newbrk, oldbrk;
	struct mm_struct *mm = current->mm;

	/*
	 * Most of this replicates the code in sys_brk() except for an additional safety
	 * check and the clearing of r8.  However, we can't call sys_brk() because we need
	 * to acquire the mmap_sem before we can do the test...
	 */
	down(&mm->mmap_sem);

	if (brk < mm->end_code)
		goto out;
	newbrk = PAGE_ALIGN(brk);
	oldbrk = PAGE_ALIGN(mm->brk);
	if (oldbrk == newbrk)
		goto set_brk;

	/* Always allow shrinking brk. */
	if (brk <= mm->brk) {
		if (!do_munmap(mm, newbrk, oldbrk-newbrk))
			goto set_brk;
		goto out;
	}

	/* Check against unimplemented/unmapped addresses: */
	if ((newbrk - oldbrk) > RGN_MAP_LIMIT || rgn_offset(newbrk) > RGN_MAP_LIMIT)
		goto out;

	/* Check against rlimit.. */
	rlim = current->rlim[RLIMIT_DATA].rlim_cur;
	if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
		goto out;

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

	/* Check if we have enough memory.. */
	if (!vm_enough_memory((newbrk-oldbrk) >> PAGE_SHIFT))
		goto out;

	/* Ok, looks good - let it rip. */
	if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
		goto out;
set_brk:
	mm->brk = brk;
out:
	retval = mm->brk;
	up(&mm->mmap_sem);
	regs->r8 = 0;		/* ensure large retval isn't mistaken as error code */
	return retval;
}

/*
 * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
 * and r9) as this is faster than doing a copy_to_user().
 */
asmlinkage long
sys_pipe (long arg0, long arg1, long arg2, long arg3,
	  long arg4, long arg5, long arg6, long arg7, long stack)
{
	struct pt_regs *regs = (struct pt_regs *) &stack;
	int fd[2];
	int retval;

	retval = do_pipe(fd);
	if (retval)
		goto out;
	retval = fd[0];
	regs->r9 = fd[1];
  out:
	return retval;
}

static inline unsigned long
do_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, unsigned long pgoff)
{
	unsigned long roff;
	struct file *file = 0;

	/*
	 * A zero mmap always succeeds in Linux, independent of
	 * whether or not the remaining arguments are valid.
	 */
	if (PAGE_ALIGN(len) == 0)
		return addr;

	/* don't permit mappings into unmapped space or the virtual page table of a region: */
	roff = rgn_offset(addr);
	if ((len | roff | (roff + len)) >= RGN_MAP_LIMIT)
		return -EINVAL;

	/* don't permit mappings that would cross a region boundary: */
	if (rgn_index(addr) != rgn_index(addr + len))
		return -EINVAL;

	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
	if (!(flags & MAP_ANONYMOUS)) {
		file = fget(fd);
		if (!file)
			return -EBADF;
	}

	if (flags & MAP_SHARED)
		current->thread.flags |= IA64_THREAD_MAP_SHARED;

	down(&current->mm->mmap_sem);
	addr = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
	up(&current->mm->mmap_sem);

	current->thread.flags &= ~IA64_THREAD_MAP_SHARED;

	if (file)
		fput(file);
	return addr;
}

/*
 * mmap2() is like mmap() except that the offset is expressed in units
 * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
 * of) files that are larger than the address space of the CPU.
 */
asmlinkage unsigned long
sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff,
	   long arg6, long arg7, long stack)
{
	struct pt_regs *regs = (struct pt_regs *) &stack;

	addr = do_mmap2(addr, len, prot, flags, fd, pgoff);
	if (!IS_ERR((void *) addr))
		regs->r8 = 0;	/* ensure large addresses are not mistaken as failures... */
	return addr;
}

asmlinkage unsigned long
sys_mmap (unsigned long addr, unsigned long len, int prot, int flags,
	  int fd, long off, long arg6, long arg7, long stack)
{
	struct pt_regs *regs = (struct pt_regs *) &stack;

	if ((off & ~PAGE_MASK) != 0)
		return -EINVAL;

	addr = do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
	if (!IS_ERR((void *) addr))
		regs->r8 = 0;	/* ensure large addresses are not mistaken as failures... */
	return addr;
}

asmlinkage long
sys_vm86 (long arg0, long arg1, long arg2, long arg3)
{
        printk(KERN_ERR "sys_vm86(%lx, %lx, %lx, %lx)!\n", arg0, arg1, arg2, arg3);
        return -ENOSYS;
}

asmlinkage long
sys_modify_ldt (long arg0, long arg1, long arg2, long arg3)
{
        printk(KERN_ERR "sys_modify_ldt(%lx, %lx, %lx, %lx)!\n", arg0, arg1, arg2, arg3);
        return -ENOSYS;
}

asmlinkage unsigned long
ia64_create_module (const char *name_user, size_t size, long arg2, long arg3,
		    long arg4, long arg5, long arg6, long arg7, long stack)
{
	extern unsigned long sys_create_module (const char *, size_t);
	struct pt_regs *regs = (struct pt_regs *) &stack;
	unsigned long   addr;

	addr = sys_create_module (name_user, size);
	if (!IS_ERR((void *) addr))
		regs->r8 = 0;	/* ensure large addresses are not mistaken as failures... */
	return addr;
}

#if 1
/*
 * This is here for a while to keep compatibillity with the old stat()
 * call - it will be removed later once everybody migrates to the new
 * kernel stat structure that matches the glibc one - Jes
 */
static __inline__ int
do_revalidate (struct dentry *dentry)
{
	struct inode * inode = dentry->d_inode;
	if (inode->i_op && inode->i_op->revalidate)
		return inode->i_op->revalidate(dentry);
	return 0;
}

static int
cp_ia64_old_stat (struct inode *inode, struct ia64_oldstat *statbuf)
{
	struct ia64_oldstat tmp;
	unsigned int blocks, indirect;

	memset(&tmp, 0, sizeof(tmp));
	tmp.st_dev = kdev_t_to_nr(inode->i_dev);
	tmp.st_ino = inode->i_ino;
	tmp.st_mode = inode->i_mode;
	tmp.st_nlink = inode->i_nlink;
	SET_STAT_UID(tmp, inode->i_uid);
	SET_STAT_GID(tmp, inode->i_gid);
	tmp.st_rdev = kdev_t_to_nr(inode->i_rdev);
	tmp.st_size = inode->i_size;
	tmp.st_atime = inode->i_atime;
	tmp.st_mtime = inode->i_mtime;
	tmp.st_ctime = inode->i_ctime;
/*
 * st_blocks and st_blksize are approximated with a simple algorithm if
 * they aren't supported directly by the filesystem. The minix and msdos
 * filesystems don't keep track of blocks, so they would either have to
 * be counted explicitly (by delving into the file itself), or by using
 * this simple algorithm to get a reasonable (although not 100% accurate)
 * value.
 */

/*
 * Use minix fs values for the number of direct and indirect blocks.  The
 * count is now exact for the minix fs except that it counts zero blocks.
 * Everything is in units of BLOCK_SIZE until the assignment to
 * tmp.st_blksize.
 */
#define D_B   7
#define I_B   (BLOCK_SIZE / sizeof(unsigned short))

	if (!inode->i_blksize) {
		blocks = (tmp.st_size + BLOCK_SIZE - 1) / BLOCK_SIZE;
		if (blocks > D_B) {
			indirect = (blocks - D_B + I_B - 1) / I_B;
			blocks += indirect;
			if (indirect > 1) {
				indirect = (indirect - 1 + I_B - 1) / I_B;
				blocks += indirect;
				if (indirect > 1)
					blocks++;
			}
		}
		tmp.st_blocks = (BLOCK_SIZE / 512) * blocks;
		tmp.st_blksize = BLOCK_SIZE;
	} else {
		tmp.st_blocks = inode->i_blocks;
		tmp.st_blksize = inode->i_blksize;
	}
	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
}

asmlinkage long
ia64_oldstat (char *filename, struct ia64_oldstat *statbuf)
{
	struct nameidata nd;
	int error;

	error = user_path_walk(filename, &nd);
	if (!error) {
		error = do_revalidate(nd.dentry);
		if (!error)
		error = cp_ia64_old_stat(nd.dentry->d_inode, statbuf);
		path_release(&nd);
	}
	return error;
}


asmlinkage long
ia64_oldlstat (char *filename, struct ia64_oldstat *statbuf) {
	struct nameidata nd;
	int error;

	error = user_path_walk_link(filename, &nd);
	if (!error) {
		error = do_revalidate(nd.dentry);
		if (!error)
			error = cp_ia64_old_stat(nd.dentry->d_inode, statbuf);
		path_release(&nd);
	}
	return error;
}

asmlinkage long
ia64_oldfstat (unsigned int fd, struct ia64_oldstat *statbuf)
{
	struct file * f;
	int err = -EBADF;

	f = fget(fd);
	if (f) {
		struct dentry * dentry = f->f_dentry;

		err = do_revalidate(dentry);
		if (!err)
			err = cp_ia64_old_stat(dentry->d_inode, statbuf);
		fput(f);
	}
	return err;
}
 
#endif

#ifndef CONFIG_PCI

asmlinkage long
sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
		    void *buf)
{
	return -ENOSYS;
}

asmlinkage long
sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
		     void *buf)
{
	return -ENOSYS;
}

#endif /* CONFIG_PCI */