1 /* 2 * Copyright (c) 1992 The Regents of the University of California 3 * Copyright (c) 1990, 1992 Jan-Simon Pendry 4 * All rights reserved. 5 * 6 * This code is derived from software donated to Berkeley by 7 * Jan-Simon Pendry. 8 * 9 * %sccs.include.redist.c% 10 * 11 * @(#)fdesc_vfsops.c 1.1 (Berkeley) 06/03/92 12 * 13 * $Id: fdesc_vfsops.c,v 1.6 1992/05/30 10:25:59 jsp Exp jsp $ 14 */ 15 16 /* 17 * /dev/fd Filesystem 18 */ 19 20 #include <sys/param.h> 21 #include <sys/systm.h> 22 #include <sys/time.h> 23 #include <sys/types.h> 24 #include <sys/proc.h> 25 #include <sys/resourcevar.h> 26 #include <sys/filedesc.h> 27 #include <sys/vnode.h> 28 #include <sys/mount.h> 29 #include <sys/namei.h> 30 #include <sys/malloc.h> 31 #include <fdesc/fdesc.h> 32 33 static u_short fdesc_mntid; 34 35 fdesc_init() 36 { 37 #ifdef FDESC_DIAGNOSTIC 38 printf("fdesc_init\n"); /* printed during system boot */ 39 #endif 40 } 41 42 /* 43 * Mount the per-process file descriptors (/dev/fd) 44 */ 45 fdesc_mount(mp, path, data, ndp, p) 46 struct mount *mp; 47 char *path; 48 caddr_t data; 49 struct nameidata *ndp; 50 struct proc *p; 51 { 52 int error = 0; 53 u_int size; 54 struct fdescmount *fmp; 55 struct vnode *rvp; 56 57 #ifdef FDESC_DIAGNOSTIC 58 printf("fdesc_mount(mp = %x)\n", mp); 59 #endif 60 61 /* 62 * Update is a no-op 63 */ 64 if (mp->mnt_flag & MNT_UPDATE) 65 return (EOPNOTSUPP); 66 67 error = getnewvnode(VT_UFS, mp, fdesc_vnodeop_p, &rvp); /* XXX */ 68 if (error) 69 return (error); 70 71 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount), 72 M_UFSMNT, M_WAITOK); /* XXX */ 73 rvp->v_type = VDIR; 74 rvp->v_flag |= VROOT; 75 #ifdef FDESC_DIAGNOSTIC 76 printf("fdesc_mount: root vp = %x\n", rvp); 77 #endif 78 fmp->f_root = rvp; 79 mp->mnt_flag |= MNT_LOCAL; 80 mp->mnt_data = (qaddr_t) fmp; 81 getnewfsid(mp, MOUNT_FDESC); 82 83 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size); 84 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size); 85 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN); 86 bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc")); 87 #ifdef FDESC_DIAGNOSTIC 88 printf("fdesc_mount: at %s\n", mp->mnt_stat.f_mntonname); 89 #endif 90 return (0); 91 } 92 93 fdesc_start(mp, flags, p) 94 struct mount *mp; 95 int flags; 96 struct proc *p; 97 { 98 return (0); 99 } 100 101 fdesc_unmount(mp, mntflags, p) 102 struct mount *mp; 103 int mntflags; 104 struct proc *p; 105 { 106 int error; 107 int flags = 0; 108 extern int doforce; 109 struct vnode *rootvp = VFSTOFDESC(mp)->f_root; 110 111 #ifdef FDESC_DIAGNOSTIC 112 printf("fdesc_unmount(mp = %x)\n", mp); 113 #endif 114 115 if (mntflags & MNT_FORCE) { 116 /* fdesc can never be rootfs so don't check for it */ 117 if (!doforce) 118 return (EINVAL); 119 flags |= FORCECLOSE; 120 } 121 122 /* 123 * Clear out buffer cache. I don't think we 124 * ever get anything cached at this level at the 125 * moment, but who knows... 126 */ 127 #ifdef FDESC_DIAGNOSTIC 128 printf("fdesc_unmount: calling mntflushbuf\n"); 129 #endif 130 mntflushbuf(mp, 0); 131 #ifdef FDESC_DIAGNOSTIC 132 printf("fdesc_unmount: calling mntinvalbuf\n"); 133 #endif 134 if (mntinvalbuf(mp, 1)) 135 return (EBUSY); 136 if (rootvp->v_usecount > 1) 137 return (EBUSY); 138 #ifdef FDESC_DIAGNOSTIC 139 printf("fdesc_unmount: calling vflush\n"); 140 #endif 141 if (error = vflush(mp, rootvp, flags)) 142 return (error); 143 144 #ifdef FDESC_DIAGNOSTIC 145 vprint("fdesc root", rootvp); 146 #endif 147 /* 148 * Release reference on underlying root vnode 149 */ 150 vrele(rootvp); 151 /* 152 * And blow it away for future re-use 153 */ 154 vgone(rootvp); 155 /* 156 * Finally, throw away the fdescmount structure 157 */ 158 free(mp->mnt_data, M_UFSMNT); /* XXX */ 159 mp->mnt_data = 0; 160 return 0; 161 } 162 163 fdesc_root(mp, vpp) 164 struct mount *mp; 165 struct vnode **vpp; 166 { 167 USES_VOP_LOCK; 168 struct vnode *vp; 169 int error; 170 171 #ifdef FDESC_DIAGNOSTIC 172 printf("fdesc_root(mp = %x)\n", mp); 173 #endif 174 175 /* 176 * Return locked reference to root. 177 */ 178 #ifdef FDESC_DIAGNOSTIC 179 printf("fdesc_root: fdesc = %x\n", VFSTOFDESC(mp)); 180 #endif 181 vp = VFSTOFDESC(mp)->f_root; 182 #ifdef FDESC_DIAGNOSTIC 183 printf("fdesc_root: root = %x\n", vp); 184 #endif 185 VREF(vp); 186 #ifdef FDESC_DIAGNOSTIC 187 printf("fdesc_root: calling VOP_LOCK\n"); 188 #endif 189 VOP_LOCK(vp); 190 #ifdef FDESC_DIAGNOSTIC 191 printf("fdesc_root: back from VOP_LOCK\n"); 192 #endif 193 *vpp = vp; 194 #ifdef FDESC_DIAGNOSTIC 195 printf("fdesc_root(mp = %x) = %x\n", mp, vp); 196 #endif 197 return (0); 198 } 199 200 fdesc_quotactl(mp, cmd, uid, arg, p) 201 struct mount *mp; 202 int cmd; 203 uid_t uid; 204 caddr_t arg; 205 struct proc *p; 206 { 207 return (EOPNOTSUPP); 208 } 209 210 fdesc_statfs(mp, sbp, p) 211 struct mount *mp; 212 struct statfs *sbp; 213 struct proc *p; 214 { 215 struct filedesc *fdp; 216 int lim; 217 int i; 218 int last; 219 int freefd; 220 221 #ifdef FDESC_DIAGNOSTIC 222 printf("fdesc_statfs(mp = %x)\n", mp); 223 #endif 224 225 /* 226 * Compute number of free file descriptors. 227 * [ Strange results will ensue if the open file 228 * limit is ever reduced below the current number 229 * of open files... ] 230 */ 231 lim = p->p_rlimit[RLIMIT_OFILE].rlim_cur; 232 fdp = p->p_fd; 233 last = min(fdp->fd_nfiles, lim); 234 freefd = 0; 235 for (i = fdp->fd_freefile; i < last; i++) 236 if (fdp->fd_ofiles[i] == NULL) 237 freefd++; 238 239 /* 240 * Adjust for the fact that the fdesc array may not 241 * have been fully allocated yet. 242 */ 243 if (fdp->fd_nfiles < lim) 244 freefd += (lim - fdp->fd_nfiles); 245 246 sbp->f_type = MOUNT_FDESC; 247 sbp->f_flags = 0; 248 sbp->f_bsize = DEV_BSIZE; 249 sbp->f_iosize = DEV_BSIZE; 250 sbp->f_blocks = 2; /* 1K to keep df happy */ 251 sbp->f_bfree = 0; 252 sbp->f_bavail = 0; 253 sbp->f_files = lim + 1; /* Allow for "." */ 254 sbp->f_ffree = freefd; /* See comments above */ 255 if (sbp != &mp->mnt_stat) { 256 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid)); 257 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN); 258 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN); 259 } 260 return (0); 261 } 262 263 fdesc_sync(mp, waitfor) 264 struct mount *mp; 265 int waitfor; 266 { 267 return (0); 268 } 269 270 fdesc_fhtovp(mp, fhp, setgen, vpp) 271 struct mount *mp; 272 struct fid *fhp; 273 int setgen; 274 struct vnode **vpp; 275 { 276 return (EOPNOTSUPP); 277 } 278 279 fdesc_vptofh(vp, fhp) 280 struct vnode *vp; 281 struct fid *fhp; 282 { 283 return (EOPNOTSUPP); 284 } 285 286 struct vfsops fdesc_vfsops = { 287 fdesc_mount, 288 fdesc_start, 289 fdesc_unmount, 290 fdesc_root, 291 fdesc_quotactl, 292 fdesc_statfs, 293 fdesc_sync, 294 fdesc_fhtovp, 295 fdesc_vptofh, 296 fdesc_init, 297 }; 298