Пример #1
0
int mmap_exec(u_int k, int envid, int execonly) {
  /* munmap all non-MAP_INHERIT regions */
  struct Mmap *m2, *m = mmap_list.lh_first;

  if (!execonly) return 0;

  while (m)
    if (m->mmap_flags & MAP_INHERIT) {
      /* not implemented - need to set up a region of vm to mmap data */
      assert(0);
      m = m->mmap_link.le_next;
    }
    else {
      m2 = m->mmap_link.le_next;
      assert(msync(m->mmap_addr, m->mmap_len, 0) == 0);
      if (m->mmap_filp) {
	lock_filp(m->mmap_filp);
	filp_refcount_dec(m->mmap_filp);
	if (filp_refcount_get(m->mmap_filp) == 0) {
	  unlock_filp(m->mmap_filp);
	  close_filp(m->mmap_filp);
	} else
	  unlock_filp(m->mmap_filp);
      }
      m = m2;
    }

  return 0;
}
Пример #2
0
/*===========================================================================*
 *				do_lseek				     *
 *===========================================================================*/
int do_lseek()
{
/* Perform the lseek(ls_fd, offset, whence) system call. */
  register struct filp *rfilp;
  int r = OK, seekfd, seekwhence;
  off_t offset;
  u64_t pos, newpos;

  seekfd = job_m_in.ls_fd;
  seekwhence = job_m_in.whence;
  offset = (off_t) job_m_in.offset_lo;

  /* Check to see if the file descriptor is valid. */
  if ( (rfilp = get_filp(seekfd, VNODE_READ)) == NULL) return(err_code);

  /* No lseek on pipes. */
  if (S_ISFIFO(rfilp->filp_vno->v_mode)) {
	unlock_filp(rfilp);
	return(ESPIPE);
  }

  /* The value of 'whence' determines the start position to use. */
  switch(seekwhence) {
    case SEEK_SET: pos = cvu64(0);	break;
    case SEEK_CUR: pos = rfilp->filp_pos;	break;
    case SEEK_END: pos = cvul64(rfilp->filp_vno->v_size);	break;
    default: unlock_filp(rfilp); return(EINVAL);
  }

  if (offset >= 0)
	newpos = add64ul(pos, offset);
  else
	newpos = sub64ul(pos, -offset);

  /* Check for overflow. */
  if (ex64hi(newpos) != 0) {
	r = EOVERFLOW;
  } else if ((off_t) ex64lo(newpos) < 0) { /* no negative file size */
	r = EOVERFLOW;
  } else {
	/* insert the new position into the output message */
	m_out.reply_l1 = ex64lo(newpos);

	if (cmp64(newpos, rfilp->filp_pos) != 0) {
		rfilp->filp_pos = newpos;

		/* Inhibit read ahead request */
		r = req_inhibread(rfilp->filp_vno->v_fs_e,
				  rfilp->filp_vno->v_inode_nr);
	}
  }

  unlock_filp(rfilp);
  return(r);
}
Пример #3
0
/*===========================================================================*
 *				actual_llseek				     *
 *===========================================================================*/
int actual_llseek(struct fproc *rfp, message *m_out, int seekfd, int seekwhence,
	u64_t offset)
{
/* Perform the llseek(ls_fd, offset, whence) system call. */
  register struct filp *rfilp;
  u64_t pos, newpos;
  int r = OK;
  long off_hi = ex64hi(offset);

  /* Check to see if the file descriptor is valid. */
  if ( (rfilp = get_filp2(rfp, seekfd, VNODE_READ)) == NULL) {
	return(err_code);
  }

  /* No lseek on pipes. */
  if (S_ISFIFO(rfilp->filp_vno->v_mode)) {
	unlock_filp(rfilp);
	return(ESPIPE);
  }

  /* The value of 'whence' determines the start position to use. */
  switch(seekwhence) {
    case SEEK_SET: pos = cvu64(0);	break;
    case SEEK_CUR: pos = rfilp->filp_pos;	break;
    case SEEK_END: pos = cvul64(rfilp->filp_vno->v_size);	break;
    default: unlock_filp(rfilp); return(EINVAL);
  }

  newpos = pos + offset;

  /* Check for overflow. */
  if ((off_hi > 0) && cmp64(newpos, pos) < 0)
      r = EINVAL;
  else if ((off_hi < 0) && cmp64(newpos, pos) > 0)
      r = EINVAL;
  else {
	/* insert the new position into the output message */
	m_out->reply_l1 = ex64lo(newpos);
	m_out->reply_l2 = ex64hi(newpos);

	if (cmp64(newpos, rfilp->filp_pos) != 0) {
		rfilp->filp_pos = newpos;

		/* Inhibit read ahead request */
		r = req_inhibread(rfilp->filp_vno->v_fs_e,
				  rfilp->filp_vno->v_inode_nr);
	}
  }

  unlock_filp(rfilp);
  return(r);
}
Пример #4
0
Файл: misc.c Проект: wieck/minix
int dupvm(struct fproc *rfp, int pfd, int *vmfd, struct filp **newfilp)
{
	int result, procfd;
	struct filp *f = NULL;
	struct fproc *vmf = &fproc[VM_PROC_NR];

	*newfilp = NULL;

	if ((f = get_filp2(rfp, pfd, VNODE_READ)) == NULL) {
		printf("VFS dupvm: get_filp2 failed\n");
		return EBADF;
	}

	if(!f->filp_vno->v_vmnt->m_haspeek) {
		unlock_filp(f);
		printf("VFS dupvm: no peek available\n");
		return EINVAL;
	}

	assert(f->filp_vno);
	assert(f->filp_vno->v_vmnt);

	if (!S_ISREG(f->filp_vno->v_mode) && !S_ISBLK(f->filp_vno->v_mode)) {
		printf("VFS: mmap regular/blockdev only; dev 0x%x ino %d has mode 0%o\n",
			(int) f->filp_vno->v_dev, (int) f->filp_vno->v_inode_nr, (int) f->filp_vno->v_mode);
		unlock_filp(f);
		return EINVAL;
	}

	/* get free FD in VM */
	if((result=get_fd(vmf, 0, 0, &procfd, NULL)) != OK) {
		unlock_filp(f);
		printf("VFS dupvm: getfd failed\n");
		return result;
	}

	*vmfd = procfd;

	f->filp_count++;
	assert(f->filp_count > 0);
	vmf->fp_filp[procfd] = f;

	/* mmap FD's are inuse */
	FD_SET(procfd, &vmf->fp_filp_inuse);

	*newfilp = f;

	return OK;
}
/*===========================================================================*
 *				actual_lseek				     *
 *===========================================================================*/
int actual_lseek(struct fproc *rfp, int seekfd, int seekwhence, off_t offset,
	off_t *newposp)
{
  register struct filp *rfilp;
  int r = OK;
  off_t pos, newpos;

  /* Check to see if the file descriptor is valid. */
  if ( (rfilp = get_filp2(rfp, seekfd, VNODE_READ)) == NULL) {
	return(err_code);
  }

  /* No lseek on pipes. */
  if (S_ISFIFO(rfilp->filp_vno->v_mode)) {
	unlock_filp(rfilp);
	return(ESPIPE);
  }

  /* The value of 'whence' determines the start position to use. */
  switch(seekwhence) {
    case SEEK_SET: pos = 0; break;
    case SEEK_CUR: pos = rfilp->filp_pos; break;
    case SEEK_END: pos = rfilp->filp_vno->v_size; break;
    default: unlock_filp(rfilp); return(EINVAL);
  }

  newpos = pos + offset;

  /* Check for overflow. */
  if ((offset > 0) && (newpos <= pos)) {
	r = EOVERFLOW;
  } else if ((offset < 0) && (newpos >= pos)) {
	r = EOVERFLOW;
  } else {
	if (newposp != NULL) *newposp = newpos;

	if (newpos != rfilp->filp_pos) {
		rfilp->filp_pos = newpos;

		/* Inhibit read ahead request */
		r = req_inhibread(rfilp->filp_vno->v_fs_e,
				  rfilp->filp_vno->v_inode_nr);
	}
  }

  unlock_filp(rfilp);
  return(r);
}
Пример #6
0
/*===========================================================================*
 *				do_dup					     *
 *===========================================================================*/
int do_dup()
{
/* Perform the dup(fd) or dup2(fd,fd2) system call. These system calls are
 * obsolete.  In fact, it is not even possible to invoke them using the
 * current library because the library routines call fcntl().  They are
 * provided to permit old binary programs to continue to run.
 */

  int rfd, rfd2;
  struct filp *f;
  int r = OK;

  scratch(fp).file.fd_nr = job_m_in.fd;
  rfd2 = job_m_in.fd2;

  /* Is the file descriptor valid? */
  rfd = scratch(fp).file.fd_nr & ~DUP_MASK;	/* kill off dup2 bit, if on */
  if ((f = get_filp(rfd, VNODE_READ)) == NULL) return(err_code);

  /* Distinguish between dup and dup2. */
  if (!(scratch(fp).file.fd_nr & DUP_MASK)) {		/* bit not on */
	/* dup(fd) */
	r = get_fd(0, 0, &rfd2, NULL);
  } else {
	/* dup2(old_fd, new_fd) */
	if (rfd2 < 0 || rfd2 >= OPEN_MAX) {
		r = EBADF;
	} else if (rfd == rfd2) {	/* ignore the call: dup2(x, x) */
		r = rfd2;
	} else {
		/* All is fine, close new_fd if necessary */
		unlock_filp(f);		/* or it might deadlock on do_close */
		(void) close_fd(fp, rfd2);	/* cannot fail */
		f = get_filp(rfd, VNODE_READ); /* lock old_fd again */
	}
  }

  if (r == OK) {
	/* Success. Set up new file descriptors. */
	f->filp_count++;
	fp->fp_filp[rfd2] = f;
	FD_SET(rfd2, &fp->fp_filp_inuse);
	r = rfd2;
  }

  unlock_filp(f);
  return(r);
}
Пример #7
0
int dupvm(struct fproc *rfp, int pfd, int *vmfd, struct filp **newfilp)
{
	int result, procfd;
	struct filp *f = NULL;
	struct fproc *vmf = fproc_addr(VM_PROC_NR);

	*newfilp = NULL;

	if ((f = get_filp2(rfp, pfd, VNODE_READ)) == NULL) {
		printf("VFS dupvm: get_filp2 failed\n");
		return EBADF;
	}

	if(!(f->filp_vno->v_vmnt->m_fs_flags & RES_HASPEEK)) {
		unlock_filp(f);
#if 0	/* Noisy diagnostic for mmap() by ld.so */
		printf("VFS dupvm: no peek available\n");
#endif
		return EINVAL;
	}

	assert(f->filp_vno);
	assert(f->filp_vno->v_vmnt);

	if (!S_ISREG(f->filp_vno->v_mode) && !S_ISBLK(f->filp_vno->v_mode)) {
		printf("VFS: mmap regular/blockdev only; dev 0x%llx ino %llu has mode 0%o\n",
			f->filp_vno->v_dev, f->filp_vno->v_inode_nr, f->filp_vno->v_mode);
		unlock_filp(f);
		return EINVAL;
	}

	/* get free FD in VM */
	if((result=get_fd(vmf, 0, 0, &procfd, NULL)) != OK) {
		unlock_filp(f);
		printf("VFS dupvm: getfd failed\n");
		return result;
	}

	*vmfd = procfd;

	f->filp_count++;
	assert(f->filp_count > 0);
	vmf->fp_filp[procfd] = f;

	*newfilp = f;

	return OK;
}
Пример #8
0
/*===========================================================================*
 *				do_llseek				     *
 *===========================================================================*/
PUBLIC int do_llseek()
{
/* Perform the llseek(ls_fd, offset, whence) system call. */
  register struct filp *rfilp;
  u64_t pos, newpos;
  int r = OK;

  /* Check to see if the file descriptor is valid. */
  if ( (rfilp = get_filp(m_in.ls_fd, VNODE_READ)) == NULL) return(err_code);

  /* No lseek on pipes. */
  if (rfilp->filp_vno->v_pipe == I_PIPE) {
	unlock_filp(rfilp);
	return(ESPIPE);
  }

  /* The value of 'whence' determines the start position to use. */
  switch(m_in.whence) {
    case SEEK_SET: pos = cvu64(0);	break;
    case SEEK_CUR: pos = rfilp->filp_pos;	break;
    case SEEK_END: pos = cvul64(rfilp->filp_vno->v_size);	break;
    default: unlock_filp(rfilp); return(EINVAL);
  }

  newpos = add64(pos, make64(m_in.offset_lo, m_in.offset_high));

  /* Check for overflow. */
  if (( (long) m_in.offset_high > 0) && cmp64(newpos, pos) < 0)
      r = EINVAL;
  else if (( (long) m_in.offset_high < 0) && cmp64(newpos, pos) > 0)
      r = EINVAL;
  else {
	rfilp->filp_pos = newpos;

	/* insert the new position into the output message */
	m_out.reply_l1 = ex64lo(newpos);
	m_out.reply_l2 = ex64hi(newpos);

	if (cmp64(newpos, rfilp->filp_pos) != 0) {
		/* Inhibit read ahead request */
		r = req_inhibread(rfilp->filp_vno->v_fs_e,
				  rfilp->filp_vno->v_inode_nr);
	}
  }

  unlock_filp(rfilp);
  return(r);
}
Пример #9
0
/*===========================================================================*
 *			       do_pending_pipe				     *
 *===========================================================================*/
static void do_pending_pipe(void)
{
  int r, op;
  struct filp *f;
  tll_access_t locktype;

  f = fp->fp_filp[fp->fp_fd];
  assert(f != NULL);

  locktype = (job_call_nr == VFS_READ) ? VNODE_READ : VNODE_WRITE;
  op = (job_call_nr == VFS_READ) ? READING : WRITING;
  lock_filp(f, locktype);

  r = rw_pipe(op, who_e, f, fp->fp_io_buffer, fp->fp_io_nbytes);

  if (r != SUSPEND) { /* Do we have results to report? */
	/* Process is writing, but there is no reader. Send a SIGPIPE signal.
	 * This should match the corresponding code in read_write().
	 */
	if (r == EPIPE && op == WRITING) {
		if (!(f->filp_flags & O_NOSIGPIPE))
			sys_kill(fp->fp_endpoint, SIGPIPE);
	}

	replycode(fp->fp_endpoint, r);
  }

  unlock_filp(f);
}
Пример #10
0
/*===========================================================================*
 *				do_fsync				     *
 *===========================================================================*/
PUBLIC int do_fsync()
{
/* Perform the fsync() system call. */
  struct filp *rfilp;
  struct vmnt *vmp;
  dev_t dev;
  int r = OK;

  if ((rfilp = get_filp(m_in.m1_i1, VNODE_READ)) == NULL) return(err_code);
  dev = rfilp->filp_vno->v_dev;
  for (vmp = &vmnt[0]; vmp < &vmnt[NR_MNTS]; ++vmp) {
	if (vmp->m_dev != NO_DEV && vmp->m_dev == dev &&
		vmp->m_fs_e != NONE && vmp->m_root_node != NULL) {

		if ((r = lock_vmnt(vmp, VMNT_EXCL)) != OK)
			break;
		req_sync(vmp->m_fs_e);
		unlock_vmnt(vmp);
	}
  }

  unlock_filp(rfilp);

  return(r);
}
Пример #11
0
/*===========================================================================*
 *				do_getdents				     *
 *===========================================================================*/
int do_getdents(void)
{
/* Perform the getdents(fd, buf, size) system call. */
  int r = OK;
  off_t new_pos;
  register struct filp *rfilp;

  scratch(fp).file.fd_nr = job_m_in.m_lc_vfs_readwrite.fd;
  scratch(fp).io.io_buffer = job_m_in.m_lc_vfs_readwrite.buf;
  scratch(fp).io.io_nbytes = job_m_in.m_lc_vfs_readwrite.len;

  /* Is the file descriptor valid? */
  if ( (rfilp = get_filp(scratch(fp).file.fd_nr, VNODE_READ)) == NULL)
	return(err_code);

  if (!(rfilp->filp_mode & R_BIT))
	r = EBADF;
  else if (!S_ISDIR(rfilp->filp_vno->v_mode))
	r = EBADF;

  if (r == OK) {
	r = req_getdents(rfilp->filp_vno->v_fs_e, rfilp->filp_vno->v_inode_nr,
			 rfilp->filp_pos, scratch(fp).io.io_buffer,
			 scratch(fp).io.io_nbytes, &new_pos, 0);

	if (r > 0) rfilp->filp_pos = new_pos;
  }

  unlock_filp(rfilp);
  return(r);
}
Пример #12
0
/*===========================================================================*
 *				do_fsync				     *
 *===========================================================================*/
int do_fsync(void)
{
/* Perform the fsync() system call. */
  struct filp *rfilp;
  struct vmnt *vmp;
  dev_t dev;
  int r = OK;

  scratch(fp).file.fd_nr = job_m_in.m_lc_vfs_fsync.fd;

  if ((rfilp = get_filp(scratch(fp).file.fd_nr, VNODE_READ)) == NULL)
	return(err_code);

  dev = rfilp->filp_vno->v_dev;
  unlock_filp(rfilp);

  for (vmp = &vmnt[0]; vmp < &vmnt[NR_MNTS]; ++vmp) {
	if (vmp->m_dev != dev) continue;
	if ((r = lock_vmnt(vmp, VMNT_READ)) != OK)
		break;
	if (vmp->m_dev != NO_DEV && vmp->m_dev == dev &&
		vmp->m_fs_e != NONE && vmp->m_root_node != NULL) {

		req_sync(vmp->m_fs_e);
	}
	unlock_vmnt(vmp);
  }

  return(r);
}
Пример #13
0
/*===========================================================================*
 *			       do_pending_pipe				     *
 *===========================================================================*/
static void *do_pending_pipe(void *arg)
{
  int r, op;
  struct job my_job;
  struct filp *f;
  tll_access_t locktype;

  my_job = *((struct job *) arg);
  fp = my_job.j_fp;

  lock_proc(fp, 1 /* force lock */);

  f = scratch(fp).file.filp;
  assert(f != NULL);
  scratch(fp).file.filp = NULL;

  locktype = (job_call_nr == READ) ? VNODE_READ : VNODE_WRITE;
  op = (job_call_nr == READ) ? READING : WRITING;
  lock_filp(f, locktype);

  r = rw_pipe(op, who_e, f, scratch(fp).io.io_buffer, scratch(fp).io.io_nbytes);

  if (r != SUSPEND)  /* Do we have results to report? */
	reply(fp->fp_endpoint, r);

  unlock_filp(f);

  thread_cleanup(fp);
  return(NULL);
}
Пример #14
0
/*===========================================================================*
 *				do_fstat				     *
 *===========================================================================*/
int do_fstat()
{
/* Perform the fstat(fd, buf) system call. */
  register struct filp *rfilp;
  int r, pipe_pos = 0, old_stat = 0, rfd;
  vir_bytes statbuf;

  statbuf = (vir_bytes) job_m_in.buffer;
  rfd = job_m_in.fd;

  if (job_call_nr == PREV_FSTAT)
	old_stat = 1;

  /* Is the file descriptor valid? */
  if ((rfilp = get_filp(rfd, VNODE_READ)) == NULL) return(err_code);

  /* If we read from a pipe, send position too */
  if (rfilp->filp_vno->v_pipe == I_PIPE) {
	if (rfilp->filp_mode & R_BIT)
		if (ex64hi(rfilp->filp_pos) != 0) {
			panic("do_fstat: bad position in pipe");
		}
	pipe_pos = ex64lo(rfilp->filp_pos);
  }

  r = req_stat(rfilp->filp_vno->v_fs_e, rfilp->filp_vno->v_inode_nr,
	       who_e, statbuf, pipe_pos, old_stat);

  unlock_filp(rfilp);

  return(r);
}
Пример #15
0
static int 
cdev_ioctl(struct file *filp, unsigned int request, char *argp) {
  int status;
  dev_t device = filp->f_dev;

  unlock_filp(filp);
  signals_off();

  status = (*cdevsw[major(device)].d_ioctl)(device, request, argp, GENFLAG(filp), curproc);

  if (status == 0) {
#if 1
    if (request == TIOCSCTTY) {
      {int ret = proc_controlt(-1,-1,(int)filp); assert(ret == 0);}
    }
#endif
  } else {
    errno = status; status = -1;
  }
  signals_on();
  /* HBXX - Race condition, can receive a signal during the return and next
     unlock_filp() */
  lock_filp(filp);
  return status;
}
Пример #16
0
void mmap_exit(void *arg) {
  /* munmap all regions */
  struct Mmap *m2, *m = mmap_list.lh_first;

  while (m) {
    m2 = m->mmap_link.le_next;
    assert(msync(m->mmap_addr, m->mmap_len, 0) == 0);
    if (m->mmap_filp) {
      lock_filp(m->mmap_filp);
      filp_refcount_dec(m->mmap_filp);
      if (filp_refcount_get(m->mmap_filp) == 0) {
	unlock_filp(m->mmap_filp);
	close_filp(m->mmap_filp);
      } else
	unlock_filp(m->mmap_filp);
    }
    m = m2;
  }
}
Пример #17
0
/*===========================================================================*
 *				do_fchdir				     *
 *===========================================================================*/
int do_fchdir()
{
  /* Change directory on already-opened fd. */
  struct filp *rfilp;
  int r, rfd;

  rfd = job_m_in.fd;

  /* Is the file descriptor valid? */
  if ((rfilp = get_filp(rfd, VNODE_READ)) == NULL) return(err_code);
  r = change_into(&fp->fp_wd, rfilp->filp_vno);
  unlock_filp(rfilp);
  return(r);
}
Пример #18
0
/*===========================================================================*
 *				actual_read_write_peek			     *
 *===========================================================================*/
int actual_read_write_peek(struct fproc *rfp, int rw_flag, int io_fd,
	vir_bytes io_buf, size_t io_nbytes)
{
/* Perform read(fd, buffer, nbytes) or write(fd, buffer, nbytes) call. */
  struct filp *f;
  tll_access_t locktype;
  int r;
  int ro = 1;

  if(rw_flag == WRITING) ro = 0;

  scratch(rfp).file.fd_nr = io_fd;
  scratch(rfp).io.io_buffer = io_buf;
  scratch(rfp).io.io_nbytes = io_nbytes;

  locktype = rw_flag == WRITING ? VNODE_WRITE : VNODE_READ;
  if ((f = get_filp2(rfp, scratch(rfp).file.fd_nr, locktype)) == NULL)
	return(err_code);

  assert(f->filp_count > 0);

  if (((f->filp_mode) & (ro ? R_BIT : W_BIT)) == 0) {
	unlock_filp(f);
	return(EBADF);
  }
  if (scratch(rfp).io.io_nbytes == 0) {
	unlock_filp(f);
	return(0);	/* so char special files need not check for 0*/
  }

  r = read_write(rfp, rw_flag, f, scratch(rfp).io.io_buffer,
	scratch(rfp).io.io_nbytes, who_e);

  unlock_filp(f);
  return(r);
}
Пример #19
0
static inline void close_filp(struct file *filp) {
  int fd;

  for (fd = NR_OPEN - 1; fd >= 0; fd--)
    if (__current->fd[fd] == NULL) {
      __current->fd[fd] = filp;
      break;
    }
  assert(fd >= 0);
  __current->cloexec_flag[fd] = 0;
  lock_filp(filp);
  filp_refcount_inc(filp);
  unlock_filp(filp);
  close(fd);
}
Пример #20
0
int mmap_fork(u_int k, int envid, int NewPid) {
  /* increase the refcounts */
  struct Mmap *m = mmap_list.lh_first;

  while (m) {
    if (m->mmap_filp) {
      lock_filp(m->mmap_filp);
      filp_refcount_inc(m->mmap_filp);
      unlock_filp(m->mmap_filp);
    }
    m = m->mmap_link.le_next;
  }

  return 0;
}
Пример #21
0
static int
cdev_write(struct file *filp, char *buffer, int nbyte, int blocking) {
  int status;
  dev_t dev = filp->f_dev;
  struct uio uio;
  struct iovec iov[4];
  char buf[CLALLOCSZ*8];
  int i;

  demand(filp, bogus filp);

  unlock_filp(filp);
  signals_off();

  DPRINTF(CLU_LEVEL,
	  ("cdev_write: filp: %08x offset: %qd nbyte: %d\n",
	   (int)filp, filp->f_pos, nbyte));

  assert(nbyte <= CLALLOCSZ*8);
  memcpy(buf,buffer,nbyte);
  iov[0].iov_base = buf;
  iov[0].iov_len = nbyte;
  uio.uio_iov = iov;
  uio.uio_iovcnt = 1;
  uio.uio_offset = 0;
  uio.uio_resid = nbyte;
  uio.uio_rw = UIO_WRITE;
  k0printf("Write: %d: ",uio.uio_resid);
  for (i = 0; i < uio.uio_resid; i++) 
    k0printf(">%d (%c)",(unsigned int)buf[i],buf[i]);

  EnterCritical();
  status = (*cdevsw[major(dev)].d_write)(dev, &uio, GENFLAG(filp));
  ExitCritical();

  k0printf("Read: %d: ",nbyte - uio.uio_resid);
  if (status == 0) {
    status = nbyte - uio.uio_resid;
  } else {
    errno = status; status = -1;
  }

  signals_on();
  /* HBXX - Race condition, can receive a signal during the return and next
     unlock_filp() */
  lock_filp(filp);
  return status;
}
Пример #22
0
static int
cdev_read(struct file *filp, char *buffer, int nbyte, int blocking) {
  int status;
  dev_t dev = filp->f_dev;
  struct uio uio;
  struct iovec iov[4];

  demand(filp, bogus filp);
  DPRINTF(CLU_LEVEL,
	  ("cdev_read: filp: %08x offset: %qd nbyte: %d\n",
	   (int)filp, filp->f_pos, nbyte));
  /* if (nbyte > CLALLOCSZ) {fprintf(stderr,"ncdev_read, warn large nbyte\n");} */
  iov[0].iov_base = buffer;
  iov[0].iov_len = nbyte;
  uio.uio_iov = iov;
  uio.uio_iovcnt = 1;
  uio.uio_offset = 0;
  uio.uio_resid = nbyte;
  uio.uio_rw = UIO_READ;

  signals_off();
  unlock_filp(filp);
  EnterCritical();
  status = (*cdevsw[major(dev)].d_read)(dev, &uio, GENFLAG(filp));
  ExitCritical();
  signals_on();

  k0printf("Read: %d: ",nbyte - uio.uio_resid);
  if (status == 0) {
    status = nbyte - uio.uio_resid;
  } else {
    errno = status; 
    status = -1;
  }
  /* HBXX - Race condition, can receive a signal during the return and next
     unlock_filp() */
  lock_filp(filp);
#if 0
  if (status >= 0) {
    extern void pr_uio();
    kprintf("read(%d,%d) ",major(dev),minor(dev));
    pr_uio(&uio);
  }
#endif
  return status;
}
Пример #23
0
/*===========================================================================*
 *				do_fstatvfs				     *
 *===========================================================================*/
int do_fstatvfs()
{
/* Perform the fstat(fd, buf) system call. */
  register struct filp *rfilp;
  int r, rfd;
  vir_bytes statbuf;

  rfd = job_m_in.fd;
  statbuf = (vir_bytes) job_m_in.name2;

  /* Is the file descriptor valid? */
  if ((rfilp = get_filp(rfd, VNODE_READ)) == NULL) return(err_code);
  r = req_statvfs(rfilp->filp_vno->v_fs_e, who_e, statbuf);

  unlock_filp(rfilp);

  return(r);
}
/*===========================================================================*
 *			       do_pending_pipe				     *
 *===========================================================================*/
static void do_pending_pipe(void)
{
  vir_bytes buf;
  size_t nbytes, cum_io;
  int r, op, fd;
  struct filp *f;
  tll_access_t locktype;

  assert(fp->fp_blocked_on == FP_BLOCKED_ON_NONE);

  /*
   * We take all our needed resumption state from the m_in message, which is
   * filled by unblock().  Since this is an internal resumption, there is no
   * need to perform extensive checks on the message fields.
   */
  fd = job_m_in.m_lc_vfs_readwrite.fd;
  buf = job_m_in.m_lc_vfs_readwrite.buf;
  nbytes = job_m_in.m_lc_vfs_readwrite.len;
  cum_io = job_m_in.m_lc_vfs_readwrite.cum_io;

  f = fp->fp_filp[fd];
  assert(f != NULL);

  locktype = (job_call_nr == VFS_READ) ? VNODE_READ : VNODE_WRITE;
  op = (job_call_nr == VFS_READ) ? READING : WRITING;
  lock_filp(f, locktype);

  r = rw_pipe(op, who_e, f, job_call_nr, fd, buf, nbytes, cum_io);

  if (r != SUSPEND) { /* Do we have results to report? */
	/* Process is writing, but there is no reader. Send a SIGPIPE signal.
	 * This should match the corresponding code in read_write().
	 */
	if (r == EPIPE && op == WRITING) {
		if (!(f->filp_flags & O_NOSIGPIPE))
			sys_kill(fp->fp_endpoint, SIGPIPE);
	}

	replycode(fp->fp_endpoint, r);
  }

  unlock_filp(f);
}
Пример #25
0
/*===========================================================================*
 *				do_fstatvfs				     *
 *===========================================================================*/
int do_fstatvfs(void)
{
/* Perform the fstatvfs1(fd, buf, flags) system call. */
  register struct filp *rfilp;
  int r, rfd, flags;
  vir_bytes statbuf;

  rfd = job_m_in.m_lc_vfs_statvfs1.fd;
  statbuf = job_m_in.m_lc_vfs_statvfs1.buf;
  flags = job_m_in.m_lc_vfs_statvfs1.flags;

  /* Is the file descriptor valid? */
  if ((rfilp = get_filp(rfd, VNODE_READ)) == NULL) return(err_code);
  r = fill_statvfs(rfilp->filp_vno->v_vmnt, who_e, statbuf, flags);

  unlock_filp(rfilp);

  return(r);
}
Пример #26
0
/*===========================================================================*
 *				select_cancel_filp			     *
 *===========================================================================*/
static void select_cancel_filp(struct filp *f)
{
/* Reduce number of select users of this filp */

  assert(f);
  assert(f->filp_selectors >= 0);
  if (f->filp_selectors == 0) return;
  if (f->filp_count == 0) return;

  select_lock_filp(f, f->filp_select_ops);

  f->filp_selectors--;
  if (f->filp_selectors == 0) {
	/* No one selecting on this filp anymore, forget about select state */
	f->filp_select_ops = 0;
	f->filp_select_flags = 0;
	f->filp_pipe_select_ops = 0;
  }

  unlock_filp(f);
}
Пример #27
0
/*===========================================================================*
 *				do_select				     *
 *===========================================================================*/
int do_select(void)
{
/* Implement the select(nfds, readfds, writefds, errorfds, timeout) system
 * call. First we copy the arguments and verify their sanity. Then we check
 * whether there are file descriptors that satisfy the select call right of the
 * bat. If so, or if there are no ready file descriptors but the process
 * requested to return immediately, we return the result. Otherwise we set a
 * timeout and wait for either the file descriptors to become ready or the
 * timer to go off. If no timeout value was provided, we wait indefinitely. */

  int r, nfds, do_timeout = 0, fd, s;
  struct timeval timeout;
  struct selectentry *se;
  vir_bytes vtimeout;

  nfds = job_m_in.SEL_NFDS;
  vtimeout = (vir_bytes) job_m_in.SEL_TIMEOUT;

  /* Sane amount of file descriptors? */
  if (nfds < 0 || nfds > OPEN_MAX) return(EINVAL);

  /* Find a slot to store this select request */
  for (s = 0; s < MAXSELECTS; s++)
	if (selecttab[s].requestor == NULL) /* Unused slot */
		break;
  if (s >= MAXSELECTS) return(ENOSPC);

  se = &selecttab[s];
  wipe_select(se);	/* Clear results of previous usage */
  se->requestor = fp;
  se->req_endpt = who_e;
  se->vir_readfds = (fd_set *) job_m_in.SEL_READFDS;
  se->vir_writefds = (fd_set *) job_m_in.SEL_WRITEFDS;
  se->vir_errorfds = (fd_set *) job_m_in.SEL_ERRORFDS;

  /* Copy fdsets from the process */
  if ((r = copy_fdsets(se, nfds, FROM_PROC)) != OK) {
	se->requestor = NULL;
	return(r);
  }

  /* Did the process set a timeout value? If so, retrieve it. */
  if (vtimeout != 0) {
	do_timeout = 1;
	r = sys_vircopy(who_e, (vir_bytes) vtimeout, SELF, 
			(vir_bytes) &timeout, sizeof(timeout));
	if (r != OK) {
		se->requestor = NULL;
		return(r);
	}
  }

  /* No nonsense in the timeval */
  if (do_timeout && (timeout.tv_sec < 0 || timeout.tv_usec < 0)) {
	se->requestor = NULL;
	return(EINVAL);
  }

  /* If there is no timeout, we block forever. Otherwise, we block up to the
   * specified time interval.
   */
  if (!do_timeout)	/* No timeout value set */
	se->block = 1;
  else if (do_timeout && (timeout.tv_sec > 0 || timeout.tv_usec > 0))
	se->block = 1;
  else			/* timeout set as (0,0) - this effects a poll */
	se->block = 0;
  se->expiry = 0;	/* no timer set (yet) */

  /* Verify that file descriptors are okay to select on */
  for (fd = 0; fd < nfds; fd++) {
	struct filp *f;
	unsigned int type, ops;

	/* Because the select() interface implicitly includes file descriptors
	 * you might not want to select on, we have to figure out whether we're
	 * interested in them. Typically, these file descriptors include fd's
	 * inherited from the parent proc and file descriptors that have been
	 * close()d, but had a lower fd than one in the current set.
	 */
	if (!(ops = tab2ops(fd, se)))
		continue; /* No operations set; nothing to do for this fd */

	/* Get filp belonging to this fd */
	f = se->filps[fd] = get_filp(fd, VNODE_READ);
	if (f == NULL) {
		if (err_code == EBADF)
			r = err_code;
		else /* File descriptor is 'ready' to return EIO */
			r = EINTR;

		se->requestor = NULL;
		return(r);
	}

	/* Check file types. According to POSIX 2008:
	 * "The pselect() and select() functions shall support regular files,
	 * terminal and pseudo-terminal devices, FIFOs, pipes, and sockets. The
	 * behavior of pselect() and select() on file descriptors that refer to
	 * other types of file is unspecified."
	 *
	 * In our case, terminal and pseudo-terminal devices are handled by the
	 * TTY major and sockets by either INET major (socket type AF_INET) or
	 * PFS major (socket type AF_UNIX). PFS acts as an FS when it handles
	 * pipes and as a driver when it handles sockets. Additionally, we
	 * support select on the LOG major to handle kernel logging, which is
	 * beyond the POSIX spec. */

	se->type[fd] = -1;
	for (type = 0; type < SEL_FDS; type++) {
		if (fdtypes[type].type_match(f)) {
			se->type[fd] = type;
			se->nfds = fd+1;
			se->filps[fd]->filp_selectors++;
			break;
		}
	}
	unlock_filp(f);
	if (se->type[fd] == -1) { /* Type not found */
		se->requestor = NULL;
		return(EBADF);
	}
  }

  /* Check all file descriptors in the set whether one is 'ready' now */
  for (fd = 0; fd < nfds; fd++) {
	int ops, r;
	struct filp *f;

	/* Again, check for involuntarily selected fd's */
	if (!(ops = tab2ops(fd, se)))
		continue; /* No operations set; nothing to do for this fd */

	/* Test filp for select operations if not already done so. e.g.,
	 * processes sharing a filp and both doing a select on that filp. */
	f = se->filps[fd];
	if ((f->filp_select_ops & ops) != ops) {
		int wantops;

		wantops = (f->filp_select_ops |= ops);
		r = do_select_request(se, fd, &wantops);
		if (r != OK && r != SUSPEND)
			break; /* Error or bogus return code; abort */

		/* The select request above might have turned on/off some
		 * operations because they were 'ready' or not meaningful.
		 * Either way, we might have a result and we need to store them
		 * in the select table entry. */
		if (wantops & ops) ops2tab(wantops, fd, se);
	}
  }

  if ((se->nreadyfds > 0 || !se->block) && !is_deferred(se)) {
	/* fd's were found that were ready to go right away, and/or
	 * we were instructed not to block at all. Must return
	 * immediately.
	 */
	r = copy_fdsets(se, se->nfds, TO_PROC);
	select_cancel_all(se);
	se->requestor = NULL;

	if (r != OK)
		return(r);
	else if (se->error != OK)
		return(se->error);

	return(se->nreadyfds);
  }

  /* Convert timeval to ticks and set the timer. If it fails, undo
   * all, return error.
   */
  if (do_timeout) {
	int ticks;
	/* Open Group:
	 * "If the requested timeout interval requires a finer
	 * granularity than the implementation supports, the
	 * actual timeout interval shall be rounded up to the next
	 * supported value."
	 */
#define USECPERSEC 1000000
	while(timeout.tv_usec >= USECPERSEC) {
		/* this is to avoid overflow with *system_hz below */
		timeout.tv_usec -= USECPERSEC;
		timeout.tv_sec++;
	}
	ticks = timeout.tv_sec * system_hz +
		(timeout.tv_usec * system_hz + USECPERSEC-1) / USECPERSEC;
	se->expiry = ticks;
	set_timer(&se->timer, ticks, select_timeout_check, s);
  }

  /* process now blocked */
  suspend(FP_BLOCKED_ON_SELECT);
  return(SUSPEND);
}
Пример #28
0
/*===========================================================================*
 *				common_open				     *
 *===========================================================================*/
int common_open(char path[PATH_MAX], int oflags, mode_t omode)
{
/* Common code from do_creat and do_open. */
  int b, r, exist = TRUE, major_dev;
  dev_t dev;
  mode_t bits;
  struct filp *filp, *filp2;
  struct vnode *vp;
  struct vmnt *vmp;
  struct dmap *dp;
  struct lookup resolve;

  /* Remap the bottom two bits of oflags. */
  bits = (mode_t) mode_map[oflags & O_ACCMODE];
  if (!bits) return(EINVAL);

  /* See if file descriptor and filp slots are available. */
  if ((r = get_fd(0, bits, &(scratch(fp).file.fd_nr), &filp)) != OK) return(r);

  lookup_init(&resolve, path, PATH_NOFLAGS, &vmp, &vp);

  /* If O_CREATE is set, try to make the file. */
  if (oflags & O_CREAT) {
        omode = I_REGULAR | (omode & ALLPERMS & fp->fp_umask);
	vp = new_node(&resolve, oflags, omode);
	r = err_code;
	if (r == OK) exist = FALSE;	/* We just created the file */
	else if (r != EEXIST) {		/* other error */
		if (vp) unlock_vnode(vp);
		unlock_filp(filp);
		return(r);
	}
	else exist = !(oflags & O_EXCL);/* file exists, if the O_EXCL
					   flag is set this is an error */
  } else {
	/* Scan path name */
	resolve.l_vmnt_lock = VMNT_READ;
	resolve.l_vnode_lock = VNODE_OPCL;
	if ((vp = eat_path(&resolve, fp)) == NULL) {
		unlock_filp(filp);
		return(err_code);
	}

	if (vmp != NULL) unlock_vmnt(vmp);
  }

  /* Claim the file descriptor and filp slot and fill them in. */
  fp->fp_filp[scratch(fp).file.fd_nr] = filp;
  FD_SET(scratch(fp).file.fd_nr, &fp->fp_filp_inuse);
  filp->filp_count = 1;
  filp->filp_vno = vp;
  filp->filp_flags = oflags;

  /* Only do the normal open code if we didn't just create the file. */
  if (exist) {
	/* Check protections. */
	if ((r = forbidden(fp, vp, bits)) == OK) {
		/* Opening reg. files, directories, and special files differ */
		switch (vp->v_mode & S_IFMT) {
		   case S_IFREG:
			/* Truncate regular file if O_TRUNC. */
			if (oflags & O_TRUNC) {
				if ((r = forbidden(fp, vp, W_BIT)) != OK)
					break;
				truncate_vnode(vp, 0);
			}
			break;
		   case S_IFDIR:
			/* Directories may be read but not written. */
			r = (bits & W_BIT ? EISDIR : OK);
			break;
		   case S_IFCHR:
			/* Invoke the driver for special processing. */
			dev = (dev_t) vp->v_sdev;
			/* TTY needs to know about the O_NOCTTY flag. */
			r = dev_open(dev, who_e, bits | (oflags & O_NOCTTY));
			if (r == SUSPEND) suspend(FP_BLOCKED_ON_DOPEN);
			else vp = filp->filp_vno; /* Might be updated by
						   * dev_open/clone_opcl */
			break;
		   case S_IFBLK:

			lock_bsf();

			/* Invoke the driver for special processing. */
			dev = (dev_t) vp->v_sdev;
			r = bdev_open(dev, bits);
			if (r != OK) {
				unlock_bsf();
				break;
			}

			major_dev = major(vp->v_sdev);
			dp = &dmap[major_dev];
			if (dp->dmap_driver == NONE) {
				printf("VFS: block driver disappeared!\n");
				unlock_bsf();
				r = ENXIO;
				break;
			}

			/* Check whether the device is mounted or not. If so,
			 * then that FS is responsible for this device.
			 * Otherwise we default to ROOT_FS.
			 */
			vp->v_bfs_e = ROOT_FS_E; /* By default */
			for (vmp = &vmnt[0]; vmp < &vmnt[NR_MNTS]; ++vmp)
				if (vmp->m_dev == vp->v_sdev &&
				    !(vmp->m_flags & VMNT_FORCEROOTBSF)) {
					vp->v_bfs_e = vmp->m_fs_e;
				}

			/* Send the driver label to the file system that will
			 * handle the block I/O requests (even when its label
			 * and endpoint are known already), but only when it is
			 * the root file system. Other file systems will
			 * already have it anyway.
			 */
			if (vp->v_bfs_e != ROOT_FS_E) {
				unlock_bsf();
				break;
			}

			if (req_newdriver(vp->v_bfs_e, vp->v_sdev,
					dp->dmap_label) != OK) {
				printf("VFS: error sending driver label\n");
				bdev_close(dev);
				r = ENXIO;
			}
			unlock_bsf();
			break;

		   case S_IFIFO:
			/* Create a mapped inode on PFS which handles reads
			   and writes to this named pipe. */
			tll_upgrade(&vp->v_lock);
			r = map_vnode(vp, PFS_PROC_NR);
			if (r == OK) {
				if (vp->v_ref_count == 1) {
					vp->v_pipe_rd_pos = 0;
					vp->v_pipe_wr_pos = 0;
					if (vp->v_size != 0)
						r = truncate_vnode(vp, 0);
				}
				oflags |= O_APPEND;	/* force append mode */
				filp->filp_flags = oflags;
			}
			if (r == OK) {
				r = pipe_open(vp, bits, oflags);
			}
			if (r != ENXIO) {
				/* See if someone else is doing a rd or wt on
				 * the FIFO.  If so, use its filp entry so the
				 * file position will be automatically shared.
				 */
				b = (bits & R_BIT ? R_BIT : W_BIT);
				filp->filp_count = 0; /* don't find self */
				if ((filp2 = find_filp(vp, b)) != NULL) {
				    /* Co-reader or writer found. Use it.*/
				    fp->fp_filp[scratch(fp).file.fd_nr] = filp2;
				    filp2->filp_count++;
				    filp2->filp_vno = vp;
				    filp2->filp_flags = oflags;

				    /* v_count was incremented after the vnode
				     * has been found. i_count was incremented
				     * incorrectly in FS, not knowing that we
				     * were going to use an existing filp
				     * entry.  Correct this error.
				     */
				    unlock_vnode(vp);
				    put_vnode(vp);
				} else {
				    /* Nobody else found. Restore filp. */
				    filp->filp_count = 1;
				}
			}
			break;
		}
	}
  }

  unlock_filp(filp);

  /* If error, release inode. */
  if (r != OK) {
	if (r != SUSPEND) {
		fp->fp_filp[scratch(fp).file.fd_nr] = NULL;
		FD_CLR(scratch(fp).file.fd_nr, &fp->fp_filp_inuse);
		filp->filp_count = 0;
		filp->filp_vno = NULL;
		put_vnode(vp);
	}
  } else {
	r = scratch(fp).file.fd_nr;
  }

  return(r);
}
Пример #29
0
/*===========================================================================*
 *				free_proc				     *
 *===========================================================================*/
static void free_proc(int flags)
{
  int i;
  register struct fproc *rfp;
  register struct filp *rfilp;
  register struct vnode *vp;
  dev_t dev;

  if (fp->fp_endpoint == NONE)
	panic("free_proc: already free");

  if (fp_is_blocked(fp))
	unpause();

  /* Loop on file descriptors, closing any that are open. */
  for (i = 0; i < OPEN_MAX; i++) {
	(void) close_fd(fp, i);
  }

  /* Release root and working directories. */
  if (fp->fp_rd) { put_vnode(fp->fp_rd); fp->fp_rd = NULL; }
  if (fp->fp_wd) { put_vnode(fp->fp_wd); fp->fp_wd = NULL; }

  /* The rest of these actions is only done when processes actually exit. */
  if (!(flags & FP_EXITING)) return;

  fp->fp_flags |= FP_EXITING;

  /* Check if any process is SUSPENDed on this driver.
   * If a driver exits, unmap its entries in the dmap table.
   * (unmapping has to be done after the first step, because the
   * dmap table is used in the first step.)
   */
  unsuspend_by_endpt(fp->fp_endpoint);
  dmap_unmap_by_endpt(fp->fp_endpoint);

  worker_stop_by_endpt(fp->fp_endpoint); /* Unblock waiting threads */
  vmnt_unmap_by_endpt(fp->fp_endpoint); /* Invalidate open files if this
					     * was an active FS */

  /* If a session leader exits and it has a controlling tty, then revoke
   * access to its controlling tty from all other processes using it.
   */
  if ((fp->fp_flags & FP_SESLDR) && fp->fp_tty != 0) {
      dev = fp->fp_tty;
      for (rfp = &fproc[0]; rfp < &fproc[NR_PROCS]; rfp++) {
	  if(rfp->fp_pid == PID_FREE) continue;
          if (rfp->fp_tty == dev) rfp->fp_tty = 0;

          for (i = 0; i < OPEN_MAX; i++) {
		if ((rfilp = rfp->fp_filp[i]) == NULL) continue;
		if (rfilp->filp_mode == FILP_CLOSED) continue;
		vp = rfilp->filp_vno;
		if (!S_ISCHR(vp->v_mode)) continue;
		if (vp->v_sdev != dev) continue;
		lock_filp(rfilp, VNODE_READ);
		(void) cdev_close(dev); /* Ignore any errors. */
		/* FIXME: missing select check */
		rfilp->filp_mode = FILP_CLOSED;
		unlock_filp(rfilp);
          }
      }
  }

  /* Exit done. Mark slot as free. */
  fp->fp_endpoint = NONE;
  fp->fp_pid = PID_FREE;
  fp->fp_flags = FP_NOFLAGS;
}
Пример #30
0
/*===========================================================================*
 *				do_fcntl				     *
 *===========================================================================*/
int do_fcntl(void)
{
/* Perform the fcntl(fd, cmd, ...) system call. */

  register struct filp *f;
  int new_fd, fl, r = OK, fcntl_req, fcntl_argx;
  tll_access_t locktype;

  scratch(fp).file.fd_nr = job_m_in.m_lc_vfs_fcntl.fd;
  scratch(fp).io.io_buffer = job_m_in.m_lc_vfs_fcntl.arg_ptr;
  scratch(fp).io.io_nbytes = job_m_in.m_lc_vfs_fcntl.cmd;
  fcntl_req = job_m_in.m_lc_vfs_fcntl.cmd;
  fcntl_argx = job_m_in.m_lc_vfs_fcntl.arg_int;

  /* Is the file descriptor valid? */
  locktype = (fcntl_req == F_FREESP) ? VNODE_WRITE : VNODE_READ;
  if ((f = get_filp(scratch(fp).file.fd_nr, locktype)) == NULL)
	return(err_code);

  switch (fcntl_req) {
    case F_DUPFD:
	/* This replaces the old dup() system call. */
	if (fcntl_argx < 0 || fcntl_argx >= OPEN_MAX) r = EINVAL;
	else if ((r = get_fd(fp, fcntl_argx, 0, &new_fd, NULL)) == OK) {
		f->filp_count++;
		fp->fp_filp[new_fd] = f;
		r = new_fd;
	}
	break;

    case F_GETFD:
	/* Get close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	r = 0;
	if (FD_ISSET(scratch(fp).file.fd_nr, &fp->fp_cloexec_set))
		r = FD_CLOEXEC;
	break;

    case F_SETFD:
	/* Set close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	if (fcntl_argx & FD_CLOEXEC)
		FD_SET(scratch(fp).file.fd_nr, &fp->fp_cloexec_set);
	else
		FD_CLR(scratch(fp).file.fd_nr, &fp->fp_cloexec_set);
	break;

    case F_GETFL:
	/* Get file status flags (O_NONBLOCK and O_APPEND). */
	fl = f->filp_flags & (O_NONBLOCK | O_APPEND | O_ACCMODE);
	r = fl;
	break;

    case F_SETFL:
	/* Set file status flags (O_NONBLOCK and O_APPEND). */
	fl = O_NONBLOCK | O_APPEND;
	f->filp_flags = (f->filp_flags & ~fl) | (fcntl_argx & fl);
	break;

    case F_GETLK:
    case F_SETLK:
    case F_SETLKW:
	/* Set or clear a file lock. */
	r = lock_op(f, fcntl_req);
	break;

    case F_FREESP:
     {
	/* Free a section of a file */
	off_t start, end, offset;
	struct flock flock_arg;

	/* Check if it's a regular file. */
	if (!S_ISREG(f->filp_vno->v_mode)) r = EINVAL;
	else if (!(f->filp_mode & W_BIT)) r = EBADF;
	else {
		/* Copy flock data from userspace. */
		r = sys_datacopy_wrapper(who_e, scratch(fp).io.io_buffer,
			SELF, (vir_bytes) &flock_arg, sizeof(flock_arg));
	}

	if (r != OK) break;

	/* Convert starting offset to signed. */
	offset = (off_t) flock_arg.l_start;

	/* Figure out starting position base. */
	switch(flock_arg.l_whence) {
	  case SEEK_SET: start = 0; break;
	  case SEEK_CUR: start = f->filp_pos; break;
	  case SEEK_END: start = f->filp_vno->v_size; break;
	  default: r = EINVAL;
	}
	if (r != OK) break;

	/* Check for overflow or underflow. */
	if (offset > 0 && start + offset < start) r = EINVAL;
	else if (offset < 0 && start + offset > start) r = EINVAL;
	else {
		start += offset;
		if (start < 0) r = EINVAL;
	}
	if (r != OK) break;

	if (flock_arg.l_len != 0) {
		if (start >= f->filp_vno->v_size) r = EINVAL;
		else if ((end = start + flock_arg.l_len) <= start) r = EINVAL;
		else if (end > f->filp_vno->v_size) end = f->filp_vno->v_size;
	} else {
                end = 0;
	}
	if (r != OK) break;

	r = req_ftrunc(f->filp_vno->v_fs_e, f->filp_vno->v_inode_nr,start,end);

	if (r == OK && flock_arg.l_len == 0)
		f->filp_vno->v_size = start;

	break;
     }
    case F_GETNOSIGPIPE:
	r = !!(f->filp_flags & O_NOSIGPIPE);
	break;
    case F_SETNOSIGPIPE:
	if (fcntl_argx)
		f->filp_flags |= O_NOSIGPIPE;
	else
		f->filp_flags &= ~O_NOSIGPIPE;
	break;
    case F_FLUSH_FS_CACHE:
    {
	struct vnode *vn = f->filp_vno;
	mode_t mode = f->filp_vno->v_mode;
	if (!super_user) {
		r = EPERM;
	} else if (S_ISBLK(mode)) {
		/* Block device; flush corresponding device blocks. */
		r = req_flush(vn->v_bfs_e, vn->v_sdev);
	} else if (S_ISREG(mode) || S_ISDIR(mode)) {
		/* Directory or regular file; flush hosting FS blocks. */
		r = req_flush(vn->v_fs_e, vn->v_dev);
	} else {
		/* Remaining cases.. Meaning unclear. */
		r = ENODEV;
	}
	break;
    }
    default:
	r = EINVAL;
  }

  unlock_filp(f);
  return(r);
}