| 1 | /* vfs_syscalls.c 4.7 %G% */ |
| 2 | |
| 3 | #include "../h/param.h" |
| 4 | #include "../h/systm.h" |
| 5 | #include "../h/mount.h" |
| 6 | #include "../h/ino.h" |
| 7 | #include "../h/reg.h" |
| 8 | #include "../h/buf.h" |
| 9 | #include "../h/filsys.h" |
| 10 | #include "../h/dir.h" |
| 11 | #include "../h/user.h" |
| 12 | #include "../h/inode.h" |
| 13 | #include "../h/file.h" |
| 14 | #include "../h/conf.h" |
| 15 | #include "../h/stat.h" |
| 16 | #include "../h/inline.h" |
| 17 | |
| 18 | /* |
| 19 | * the fstat system call. |
| 20 | */ |
| 21 | fstat() |
| 22 | { |
| 23 | register struct file *fp; |
| 24 | register struct a { |
| 25 | int fdes; |
| 26 | struct stat *sb; |
| 27 | } *uap; |
| 28 | |
| 29 | uap = (struct a *)u.u_ap; |
| 30 | fp = getf(uap->fdes); |
| 31 | if(fp == NULL) |
| 32 | return; |
| 33 | stat1(fp->f_inode, uap->sb, fp->f_flag&FPIPE? fp->f_un.f_offset: 0); |
| 34 | } |
| 35 | |
| 36 | /* |
| 37 | * the stat system call. |
| 38 | */ |
| 39 | stat() |
| 40 | { |
| 41 | register struct inode *ip; |
| 42 | register struct a { |
| 43 | char *fname; |
| 44 | struct stat *sb; |
| 45 | } *uap; |
| 46 | |
| 47 | uap = (struct a *)u.u_ap; |
| 48 | ip = namei(uchar, 0); |
| 49 | if(ip == NULL) |
| 50 | return; |
| 51 | stat1(ip, uap->sb, (off_t)0); |
| 52 | iput(ip); |
| 53 | } |
| 54 | |
| 55 | /* |
| 56 | * The basic routine for fstat and stat: |
| 57 | * get the inode and pass appropriate parts back. |
| 58 | */ |
| 59 | stat1(ip, ub, pipeadj) |
| 60 | register struct inode *ip; |
| 61 | struct stat *ub; |
| 62 | off_t pipeadj; |
| 63 | { |
| 64 | register struct dinode *dp; |
| 65 | register struct buf *bp; |
| 66 | struct stat ds; |
| 67 | |
| 68 | IUPDAT(ip, &time, &time, 0); |
| 69 | /* |
| 70 | * first copy from inode table |
| 71 | */ |
| 72 | ds.st_dev = ip->i_dev; |
| 73 | ds.st_ino = ip->i_number; |
| 74 | ds.st_mode = ip->i_mode; |
| 75 | ds.st_nlink = ip->i_nlink; |
| 76 | ds.st_uid = ip->i_uid; |
| 77 | ds.st_gid = ip->i_gid; |
| 78 | ds.st_rdev = (dev_t)ip->i_un.i_rdev; |
| 79 | ds.st_size = ip->i_size - pipeadj; |
| 80 | /* |
| 81 | * next the dates in the disk |
| 82 | */ |
| 83 | bp = bread(ip->i_dev, itod(ip->i_number)); |
| 84 | dp = bp->b_un.b_dino; |
| 85 | dp += itoo(ip->i_number); |
| 86 | ds.st_atime = dp->di_atime; |
| 87 | ds.st_mtime = dp->di_mtime; |
| 88 | ds.st_ctime = dp->di_ctime; |
| 89 | brelse(bp); |
| 90 | if (copyout((caddr_t)&ds, (caddr_t)ub, sizeof(ds)) < 0) |
| 91 | u.u_error = EFAULT; |
| 92 | } |
| 93 | |
| 94 | /* |
| 95 | * the dup system call. |
| 96 | */ |
| 97 | dup() |
| 98 | { |
| 99 | register struct file *fp; |
| 100 | register struct a { |
| 101 | int fdes; |
| 102 | int fdes2; |
| 103 | } *uap; |
| 104 | register i, m; |
| 105 | |
| 106 | uap = (struct a *)u.u_ap; |
| 107 | m = uap->fdes & ~077; |
| 108 | uap->fdes &= 077; |
| 109 | fp = getf(uap->fdes); |
| 110 | if(fp == NULL) |
| 111 | return; |
| 112 | if ((m&0100) == 0) { |
| 113 | if ((i = ufalloc()) < 0) |
| 114 | return; |
| 115 | } else { |
| 116 | i = uap->fdes2; |
| 117 | if (i<0 || i>=NOFILE) { |
| 118 | u.u_error = EBADF; |
| 119 | return; |
| 120 | } |
| 121 | if (u.u_vrpages[i]) { |
| 122 | u.u_error = ETXTBSY; |
| 123 | return; |
| 124 | } |
| 125 | u.u_r.r_val1 = i; |
| 126 | } |
| 127 | if (i!=uap->fdes) { |
| 128 | if (u.u_ofile[i]!=NULL) |
| 129 | closef(u.u_ofile[i]); |
| 130 | u.u_ofile[i] = fp; |
| 131 | fp->f_count++; |
| 132 | } |
| 133 | } |
| 134 | |
| 135 | /* |
| 136 | * the mount system call. |
| 137 | */ |
| 138 | smount() |
| 139 | { |
| 140 | dev_t dev; |
| 141 | register struct inode *ip; |
| 142 | register struct mount *mp; |
| 143 | struct mount *smp; |
| 144 | register struct filsys *fp; |
| 145 | struct buf *bp; |
| 146 | register struct a { |
| 147 | char *fspec; |
| 148 | char *freg; |
| 149 | int ronly; |
| 150 | } *uap; |
| 151 | |
| 152 | uap = (struct a *)u.u_ap; |
| 153 | dev = getmdev(); |
| 154 | if(u.u_error) |
| 155 | return; |
| 156 | u.u_dirp = (caddr_t)uap->freg; |
| 157 | ip = namei(uchar, 0); |
| 158 | if(ip == NULL) |
| 159 | return; |
| 160 | if(ip->i_count!=1 || (ip->i_mode&(IFBLK&IFCHR))!=0) |
| 161 | goto out; |
| 162 | smp = NULL; |
| 163 | for(mp = &mount[0]; mp < &mount[NMOUNT]; mp++) { |
| 164 | if(mp->m_bufp != NULL) { |
| 165 | if(dev == mp->m_dev) |
| 166 | goto out; |
| 167 | } else |
| 168 | if(smp == NULL) |
| 169 | smp = mp; |
| 170 | } |
| 171 | mp = smp; |
| 172 | if(mp == NULL) |
| 173 | goto out; |
| 174 | (*bdevsw[major(dev)].d_open)(dev, !uap->ronly); |
| 175 | if(u.u_error) |
| 176 | goto out; |
| 177 | bp = bread(dev, SUPERB); |
| 178 | if(u.u_error) { |
| 179 | brelse(bp); |
| 180 | goto out1; |
| 181 | } |
| 182 | mp->m_inodp = ip; |
| 183 | mp->m_dev = dev; |
| 184 | bp->b_flags |= B_LOCKED; |
| 185 | mp->m_bufp = bp; |
| 186 | fp = bp->b_un.b_filsys; |
| 187 | fp->s_ilock = 0; |
| 188 | fp->s_flock = 0; |
| 189 | fp->s_ronly = uap->ronly & 1; |
| 190 | fp->s_nbehind = 0; |
| 191 | fp->s_lasti = 1; |
| 192 | brelse(bp); |
| 193 | ip->i_flag |= IMOUNT; |
| 194 | prele(ip); |
| 195 | return; |
| 196 | |
| 197 | out: |
| 198 | u.u_error = EBUSY; |
| 199 | out1: |
| 200 | iput(ip); |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * the umount system call. |
| 205 | */ |
| 206 | sumount() |
| 207 | { |
| 208 | dev_t dev; |
| 209 | register struct inode *ip; |
| 210 | register struct mount *mp; |
| 211 | struct buf *bp; |
| 212 | int stillopen, flag; |
| 213 | register struct a { |
| 214 | char *fspec; |
| 215 | }; |
| 216 | |
| 217 | dev = getmdev(); |
| 218 | if(u.u_error) |
| 219 | return; |
| 220 | xumount(dev); /* remove unused sticky files from text table */ |
| 221 | update(); |
| 222 | for(mp = &mount[0]; mp < &mount[NMOUNT]; mp++) |
| 223 | if(mp->m_bufp != NULL && dev == mp->m_dev) |
| 224 | goto found; |
| 225 | u.u_error = EINVAL; |
| 226 | return; |
| 227 | |
| 228 | found: |
| 229 | stillopen = 0; |
| 230 | for(ip = inode; ip < inodeNINODE; ip++) |
| 231 | if (ip->i_number != 0 && dev == ip->i_dev) { |
| 232 | u.u_error = EBUSY; |
| 233 | return; |
| 234 | } else if (ip->i_number != 0 && (ip->i_mode&IFMT) == IFBLK && |
| 235 | ip->i_un.i_rdev == dev) |
| 236 | stillopen++; |
| 237 | ip = mp->m_inodp; |
| 238 | ip->i_flag &= ~IMOUNT; |
| 239 | plock(ip); |
| 240 | iput(ip); |
| 241 | if ((bp = getblk(dev, SUPERB)) != mp->m_bufp) |
| 242 | panic("umount"); |
| 243 | bp->b_flags &= ~B_LOCKED; |
| 244 | flag = !bp->b_un.b_filsys->s_ronly; |
| 245 | mp->m_bufp = NULL; |
| 246 | brelse(bp); |
| 247 | mpurge(mp - &mount[0]); |
| 248 | if (!stillopen) { |
| 249 | (*bdevsw[major(dev)].d_close)(dev, flag); |
| 250 | binval(dev); |
| 251 | } |
| 252 | } |
| 253 | |
| 254 | /* |
| 255 | * Common code for mount and umount. |
| 256 | * Check that the user's argument is a reasonable |
| 257 | * thing on which to mount, and return the device number if so. |
| 258 | */ |
| 259 | dev_t |
| 260 | getmdev() |
| 261 | { |
| 262 | dev_t dev; |
| 263 | register struct inode *ip; |
| 264 | |
| 265 | if (!suser()) |
| 266 | return(NODEV); |
| 267 | ip = namei(uchar, 0); |
| 268 | if(ip == NULL) |
| 269 | return(NODEV); |
| 270 | if((ip->i_mode&IFMT) != IFBLK) |
| 271 | u.u_error = ENOTBLK; |
| 272 | dev = (dev_t)ip->i_un.i_rdev; |
| 273 | if(major(dev) >= nblkdev) |
| 274 | u.u_error = ENXIO; |
| 275 | iput(ip); |
| 276 | return(dev); |
| 277 | } |