# /* */ #include "../param.h" #include "../systm.h" #include "../reg.h" #include "../buf.h" #include "../filsys.h" #include "../user.h" #include "../inode.h" #include "../file.h" #include "../conf.h" /* * the fstat system call. */ fstat() { register *fp; fp = getf(u.u_ar0[R0]); if(fp == NULL) return; stat1(fp->f_inode, u.u_arg[0]); } /* * the stat system call. */ stat() { register ip; extern uchar; ip = namei(&uchar, 0); if(ip == NULL) return; stat1(ip, u.u_arg[1]); iput(ip); } /* * The basic routine for fstat and stat: * get the inode and pass appropriate parts back. */ stat1(ip, ub) int *ip; { register i, *bp, *cp; iupdat(ip, time); bp = bread(ip->i_dev, ldiv(ip->i_number+31, 16)); cp = bp->b_addr + 32*lrem(ip->i_number+31, 16) + 24; ip = &(ip->i_dev); for(i=0; i<14; i++) { suword(ub, *ip++); ub =+ 2; } for(i=0; i<4; i++) { suword(ub, *cp++); ub =+ 2; } brelse(bp); } /* * the dup system call. */ dup() { register i, *fp; fp = getf(u.u_ar0[R0]); if(fp == NULL) return; if ((i = ufalloc()) < 0) return; u.u_ofile[i] = fp; fp->f_count++; } /* * the mount system call. */ smount() { int d; register *ip; register struct mount *mp, *smp; extern uchar; d = getmdev(); if(u.u_error) return; u.u_dirp = u.u_arg[1]; ip = namei(&uchar, 0); if(ip == NULL) return; if(ip->i_count!=1 || (ip->i_mode&(IFBLK&IFCHR))!=0) goto out; smp = NULL; for(mp = &mount[0]; mp < &mount[NMOUNT]; mp++) { if(mp->m_bufp != NULL) { if(d == mp->m_dev) goto out; } else if(smp == NULL) smp = mp; } if(smp == NULL) goto out; (*bdevsw[d.d_major].d_open)(d, !u.u_arg[2]); if(u.u_error) goto out; mp = bread(d, 1); if(u.u_error) { brelse(mp); goto out1; } smp->m_inodp = ip; smp->m_dev = d; smp->m_bufp = getblk(NODEV); bcopy(mp->b_addr, smp->m_bufp->b_addr, 256); smp = smp->m_bufp->b_addr; smp->s_ilock = 0; smp->s_flock = 0; smp->s_ronly = u.u_arg[2] & 1; brelse(mp); ip->i_flag =| IMOUNT; prele(ip); return; out: u.u_error = EBUSY; out1: iput(ip); } /* * the umount system call. */ sumount() { int d; register struct inode *ip; register struct mount *mp; update(); d = getmdev(); if(u.u_error) return; for(mp = &mount[0]; mp < &mount[NMOUNT]; mp++) if(mp->m_bufp!=NULL && d==mp->m_dev) goto found; u.u_error = EINVAL; return; found: for(ip = &inode[0]; ip < &inode[NINODE]; ip++) if(ip->i_number!=0 && d==ip->i_dev) { u.u_error = EBUSY; return; } (*bdevsw[d.d_major].d_close)(d, 0); ip = mp->m_inodp; ip->i_flag =& ~IMOUNT; iput(ip); ip = mp->m_bufp; mp->m_bufp = NULL; brelse(ip); } /* * Common code for mount and umount. * Check that the user's argument is a reasonable * thing on which to mount, and return the device number if so. */ getmdev() { register d, *ip; extern uchar; ip = namei(&uchar, 0); if(ip == NULL) return; if((ip->i_mode&IFMT) != IFBLK) u.u_error = ENOTBLK; d = ip->i_addr[0]; if(ip->i_addr[0].d_major >= nblkdev) u.u_error = ENXIO; iput(ip); return(d); }