/* $NetBSD: kernfs_vnops.c,v 1.35 1995/02/03 16:18:46 mycroft Exp $ */ /* * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software donated to Berkeley by * Jan-Simon Pendry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kernfs_vnops.c 8.9 (Berkeley) 6/15/94 */ /* * Kernel parameter filesystem (/kern) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define KSTRING 256 /* Largest I/O available via this filesystem */ #define UIO_MX 32 #define READ_MODE (S_IRUSR|S_IRGRP|S_IROTH) #define WRITE_MODE (S_IWUSR|S_IRUSR|S_IRGRP|S_IROTH) #define DIR_MODE (S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH) struct kern_target { u_char kt_type; u_char kt_namlen; char *kt_name; void *kt_data; #define KTT_NULL 1 #define KTT_TIME 5 #define KTT_INT 17 #define KTT_STRING 31 #define KTT_HOSTNAME 47 #define KTT_AVENRUN 53 #define KTT_DEVICE 71 #define KTT_MSGBUF 89 u_char kt_tag; u_char kt_vtype; mode_t kt_mode; } kern_targets[] = { /* NOTE: The name must be less than UIO_MX-16 chars in length */ #define N(s) sizeof(s)-1, s /* name data tag type ro/rw */ { DT_DIR, N("."), 0, KTT_NULL, VDIR, DIR_MODE }, { DT_DIR, N(".."), 0, KTT_NULL, VDIR, DIR_MODE }, { DT_REG, N("boottime"), &boottime.tv_sec, KTT_INT, VREG, READ_MODE }, { DT_REG, N("copyright"), copyright, KTT_STRING, VREG, READ_MODE }, { DT_REG, N("hostname"), 0, KTT_HOSTNAME, VREG, WRITE_MODE }, { DT_REG, N("hz"), &hz, KTT_INT, VREG, READ_MODE }, { DT_REG, N("loadavg"), 0, KTT_AVENRUN, VREG, READ_MODE }, { DT_REG, N("msgbuf"), 0, KTT_MSGBUF, VREG, READ_MODE }, { DT_REG, N("pagesize"), &cnt.v_page_size, KTT_INT, VREG, READ_MODE }, { DT_REG, N("physmem"), &physmem, KTT_INT, VREG, READ_MODE }, #if 0 { DT_DIR, N("root"), 0, KTT_NULL, VDIR, DIR_MODE }, #endif { DT_BLK, N("rootdev"), &rootdev, KTT_DEVICE, VBLK, READ_MODE }, { DT_CHR, N("rrootdev"), &rrootdev, KTT_DEVICE, VCHR, READ_MODE }, { DT_REG, N("time"), 0, KTT_TIME, VREG, READ_MODE }, { DT_REG, N("version"), version, KTT_STRING, VREG, READ_MODE }, #undef N }; static int nkern_targets = sizeof(kern_targets) / sizeof(kern_targets[0]); int kernfs_xread(kt, off, bufp, len) struct kern_target *kt; int off; char **bufp; int len; { switch (kt->kt_tag) { case KTT_TIME: { struct timeval tv; microtime(&tv); sprintf(*bufp, "%d %d\n", tv.tv_sec, tv.tv_usec); break; } case KTT_INT: { int *ip = kt->kt_data; sprintf(*bufp, "%d\n", *ip); break; } case KTT_STRING: { char *cp = kt->kt_data; *bufp = cp; break; } case KTT_MSGBUF: { extern struct msgbuf *msgbufp; long n; if (off >= MSG_BSIZE) return (0); n = msgbufp->msg_bufx + off; if (n >= MSG_BSIZE) n -= MSG_BSIZE; len = min(MSG_BSIZE - n, MSG_BSIZE - off); *bufp = msgbufp->msg_bufc + n; return (len); } case KTT_HOSTNAME: { char *cp = hostname; int xlen = hostnamelen; if (xlen >= (len-2)) return (EINVAL); bcopy(cp, *bufp, xlen); (*bufp)[xlen] = '\n'; (*bufp)[xlen+1] = '\0'; break; } case KTT_AVENRUN: averunnable.fscale = FSCALE; sprintf(*bufp, "%ld %ld %ld %ld\n", averunnable.ldavg[0], averunnable.ldavg[1], averunnable.ldavg[2], averunnable.fscale); break; default: return (0); } len = strlen(*bufp); if (len <= off) return (0); *bufp += off; return (len - off); } int kernfs_xwrite(kt, buf, len) struct kern_target *kt; char *buf; int len; { switch (kt->kt_tag) { case KTT_HOSTNAME: if (buf[len-1] == '\n') --len; bcopy(buf, hostname, len); hostname[len] = '\0'; hostnamelen = len; return (0); default: return (EIO); } } /* * vp is the current namei directory * ndp is the name to locate in that directory... */ kernfs_lookup(ap) struct vop_lookup_args /* { struct vnode * a_dvp; struct vnode ** a_vpp; struct componentname * a_cnp; } */ *ap; { struct componentname *cnp = ap->a_cnp; struct vnode **vpp = ap->a_vpp; struct vnode *dvp = ap->a_dvp; char *pname = cnp->cn_nameptr; struct kern_target *kt; struct vnode *fvp; int error, i; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup(%x)\n", ap); printf("kernfs_lookup(dp = %x, vpp = %x, cnp = %x)\n", dvp, vpp, ap->a_cnp); printf("kernfs_lookup(%s)\n", pname); #endif *vpp = NULLVP; if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) return (EROFS); if (cnp->cn_namelen == 1 && *pname == '.') { *vpp = dvp; VREF(dvp); /*VOP_LOCK(dvp);*/ return (0); } #if 0 if (cnp->cn_namelen == 4 && bcmp(pname, "root", 4) == 0) { *vpp = rootdir; VREF(rootdir); VOP_LOCK(rootdir); return (0); } #endif for (kt = kern_targets, i = 0; i < nkern_targets; kt++, i++) { if (cnp->cn_namelen == kt->kt_namlen && bcmp(kt->kt_name, pname, cnp->cn_namelen) == 0) goto found; } #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup: i = %d, failed", i); #endif return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS); found: if (kt->kt_tag == KTT_DEVICE) { dev_t *dp = kt->kt_data; loop: if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp)) return (ENOENT); *vpp = fvp; if (vget(fvp, 1)) goto loop; return (0); } #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup: allocate new vnode\n"); #endif if (error = getnewvnode(VT_KERNFS, dvp->v_mount, kernfs_vnodeop_p, &fvp)) return (error); MALLOC(fvp->v_data, void *, sizeof(struct kernfs_node), M_TEMP, M_WAITOK); VTOKERN(fvp)->kf_kt = kt; fvp->v_type = kt->kt_vtype; *vpp = fvp; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup: newvp = %x\n", fvp); #endif return (0); } kernfs_open(ap) struct vop_open_args /* { struct vnode *a_vp; int a_mode; struct ucred *a_cred; struct proc *a_p; } */ *ap; { /* Only need to check access permissions. */ return (0); } int kernfs_access(ap) struct vop_access_args /* { struct vnode *a_vp; int a_mode; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct vnode *vp = ap->a_vp; mode_t fmode = (vp->v_flag & VROOT) ? DIR_MODE : VTOKERN(vp)->kf_kt->kt_mode; return (vaccess(fmode, (uid_t)0, (gid_t)0, ap->a_mode, ap->a_cred)); } kernfs_getattr(ap) struct vop_getattr_args /* { struct vnode *a_vp; struct vattr *a_vap; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct vnode *vp = ap->a_vp; struct vattr *vap = ap->a_vap; int error = 0; char strbuf[KSTRING], *buf; bzero((caddr_t) vap, sizeof(*vap)); vattr_null(vap); vap->va_uid = 0; vap->va_gid = 0; vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; vap->va_size = 0; vap->va_blocksize = DEV_BSIZE; microtime(&vap->va_atime); vap->va_mtime = vap->va_atime; vap->va_ctime = vap->va_ctime; vap->va_gen = 0; vap->va_flags = 0; vap->va_rdev = 0; vap->va_bytes = 0; if (vp->v_flag & VROOT) { #ifdef KERNFS_DIAGNOSTIC printf("kernfs_getattr: stat rootdir\n"); #endif vap->va_type = VDIR; vap->va_mode = DIR_MODE; vap->va_nlink = 2; vap->va_fileid = 2; vap->va_size = DEV_BSIZE; } else { struct kern_target *kt = VTOKERN(vp)->kf_kt; int nbytes, total; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_getattr: stat target %s\n", kt->kt_name); #endif vap->va_type = kt->kt_vtype; vap->va_mode = kt->kt_mode; vap->va_nlink = 1; vap->va_fileid = 1 + (kt - kern_targets) / sizeof(*kt); total = 0; while (buf = strbuf, nbytes = kernfs_xread(kt, total, &buf, sizeof(strbuf))) total += nbytes; vap->va_size = total; } #ifdef KERNFS_DIAGNOSTIC printf("kernfs_getattr: return error %d\n", error); #endif return (error); } kernfs_setattr(ap) struct vop_setattr_args /* { struct vnode *a_vp; struct vattr *a_vap; struct ucred *a_cred; struct proc *a_p; } */ *ap; { /* * Silently ignore attribute changes. * This allows for open with truncate to have no * effect until some data is written. I want to * do it this way because all writes are atomic. */ return (0); } int kernfs_read(ap) struct vop_read_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; struct ucred *a_cred; } */ *ap; { struct vnode *vp = ap->a_vp; struct uio *uio = ap->a_uio; struct kern_target *kt; char strbuf[KSTRING], *buf; int off, len; int error; if (vp->v_type == VDIR) return (EOPNOTSUPP); kt = VTOKERN(vp)->kf_kt; #ifdef KERNFS_DIAGNOSTIC printf("kern_read %s\n", kt->kt_name); #endif off = uio->uio_offset; #if 0 while (buf = strbuf, #else if (buf = strbuf, #endif len = kernfs_xread(kt, off, &buf, sizeof(strbuf))) { if (error = uiomove(buf, len, uio)) return (error); off += len; } return (0); } int kernfs_write(ap) struct vop_write_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; struct ucred *a_cred; } */ *ap; { struct vnode *vp = ap->a_vp; struct uio *uio = ap->a_uio; struct kern_target *kt; int error, xlen; char strbuf[KSTRING]; if (vp->v_type == VDIR) return (EOPNOTSUPP); kt = VTOKERN(vp)->kf_kt; if (uio->uio_offset != 0) return (EINVAL); xlen = min(uio->uio_resid, KSTRING-1); if (error = uiomove(strbuf, xlen, uio)) return (error); if (uio->uio_resid != 0) return (EIO); strbuf[xlen] = '\0'; xlen = strlen(strbuf); return (kernfs_xwrite(kt, strbuf, xlen)); } kernfs_readdir(ap) struct vop_readdir_args /* { struct vnode *a_vp; struct uio *a_uio; struct ucred *a_cred; int *a_eofflag; u_long *a_cookies; int a_ncookies; } */ *ap; { struct uio *uio = ap->a_uio; struct kern_target *kt; struct dirent d; int i; int error; if (ap->a_vp->v_type != VDIR) return (ENOTDIR); /* * We don't allow exporting kernfs mounts, and currently local * requests do not need cookies. */ if (ap->a_ncookies != NULL) panic("kernfs_readdir: not hungry"); i = uio->uio_offset / UIO_MX; error = 0; for (kt = &kern_targets[i]; uio->uio_resid >= UIO_MX && i < nkern_targets; kt++, i++) { struct dirent *dp = &d; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_readdir: i = %d\n", i); #endif if (kt->kt_tag == KTT_DEVICE) { dev_t *dp = kt->kt_data; struct vnode *fvp; if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp)) continue; } bzero((caddr_t)dp, UIO_MX); dp->d_namlen = kt->kt_namlen; bcopy(kt->kt_name, dp->d_name, kt->kt_namlen+1); #ifdef KERNFS_DIAGNOSTIC printf("kernfs_readdir: name = %s, len = %d\n", dp->d_name, dp->d_namlen); #endif /* * Fill in the remaining fields */ dp->d_reclen = UIO_MX; dp->d_fileno = i + 3; dp->d_type = kt->kt_type; /* * And ship to userland */ if (error = uiomove((caddr_t)dp, UIO_MX, uio)) break; } uio->uio_offset = i * UIO_MX; return (error); } kernfs_inactive(ap) struct vop_inactive_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_inactive(%x)\n", vp); #endif /* * Clear out the v_type field to avoid * nasty things happening in vgone(). */ vp->v_type = VNON; return (0); } kernfs_reclaim(ap) struct vop_reclaim_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_reclaim(%x)\n", vp); #endif if (vp->v_data) { FREE(vp->v_data, M_TEMP); vp->v_data = 0; } return (0); } /* * Return POSIX pathconf information applicable to special devices. */ kernfs_pathconf(ap) struct vop_pathconf_args /* { struct vnode *a_vp; int a_name; register_t *a_retval; } */ *ap; { switch (ap->a_name) { case _PC_LINK_MAX: *ap->a_retval = LINK_MAX; return (0); case _PC_MAX_CANON: *ap->a_retval = MAX_CANON; return (0); case _PC_MAX_INPUT: *ap->a_retval = MAX_INPUT; return (0); case _PC_PIPE_BUF: *ap->a_retval = PIPE_BUF; return (0); case _PC_CHOWN_RESTRICTED: *ap->a_retval = 1; return (0); case _PC_VDISABLE: *ap->a_retval = _POSIX_VDISABLE; return (0); default: return (EINVAL); } /* NOTREACHED */ } /* * Print out the contents of a /dev/fd vnode. */ /* ARGSUSED */ kernfs_print(ap) struct vop_print_args /* { struct vnode *a_vp; } */ *ap; { printf("tag VT_KERNFS, kernfs vnode\n"); return (0); } /*void*/ kernfs_vfree(ap) struct vop_vfree_args /* { struct vnode *a_pvp; ino_t a_ino; int a_mode; } */ *ap; { return (0); } /* * /dev/fd vnode unsupported operation */ kernfs_enotsupp() { return (EOPNOTSUPP); } /* * /dev/fd "should never get here" operation */ kernfs_badop() { panic("kernfs: bad op"); /* NOTREACHED */ } /* * kernfs vnode null operation */ kernfs_nullop() { return (0); } #define kernfs_create ((int (*) __P((struct vop_create_args *)))kernfs_enotsupp) #define kernfs_mknod ((int (*) __P((struct vop_mknod_args *)))kernfs_enotsupp) #define kernfs_close ((int (*) __P((struct vop_close_args *)))nullop) #define kernfs_ioctl ((int (*) __P((struct vop_ioctl_args *)))kernfs_enotsupp) #define kernfs_select ((int (*) __P((struct vop_select_args *)))kernfs_enotsupp) #define kernfs_mmap ((int (*) __P((struct vop_mmap_args *)))kernfs_enotsupp) #define kernfs_fsync ((int (*) __P((struct vop_fsync_args *)))nullop) #define kernfs_seek ((int (*) __P((struct vop_seek_args *)))nullop) #define kernfs_remove ((int (*) __P((struct vop_remove_args *)))kernfs_enotsupp) #define kernfs_link ((int (*) __P((struct vop_link_args *)))kernfs_enotsupp) #define kernfs_rename ((int (*) __P((struct vop_rename_args *)))kernfs_enotsupp) #define kernfs_mkdir ((int (*) __P((struct vop_mkdir_args *)))kernfs_enotsupp) #define kernfs_rmdir ((int (*) __P((struct vop_rmdir_args *)))kernfs_enotsupp) #define kernfs_symlink ((int (*) __P((struct vop_symlink_args *)))kernfs_enotsupp) #define kernfs_readlink \ ((int (*) __P((struct vop_readlink_args *)))kernfs_enotsupp) #define kernfs_abortop ((int (*) __P((struct vop_abortop_args *)))nullop) #define kernfs_lock ((int (*) __P((struct vop_lock_args *)))nullop) #define kernfs_unlock ((int (*) __P((struct vop_unlock_args *)))nullop) #define kernfs_bmap ((int (*) __P((struct vop_bmap_args *)))kernfs_badop) #define kernfs_strategy ((int (*) __P((struct vop_strategy_args *)))kernfs_badop) #define kernfs_islocked ((int (*) __P((struct vop_islocked_args *)))nullop) #define kernfs_advlock ((int (*) __P((struct vop_advlock_args *)))kernfs_enotsupp) #define kernfs_blkatoff \ ((int (*) __P((struct vop_blkatoff_args *)))kernfs_enotsupp) #define kernfs_valloc ((int(*) __P(( \ struct vnode *pvp, \ int mode, \ struct ucred *cred, \ struct vnode **vpp))) kernfs_enotsupp) #define kernfs_truncate \ ((int (*) __P((struct vop_truncate_args *)))kernfs_enotsupp) #define kernfs_update ((int (*) __P((struct vop_update_args *)))kernfs_enotsupp) #define kernfs_bwrite ((int (*) __P((struct vop_bwrite_args *)))kernfs_enotsupp) int (**kernfs_vnodeop_p)(); struct vnodeopv_entry_desc kernfs_vnodeop_entries[] = { { &vop_default_desc, vn_default_error }, { &vop_lookup_desc, kernfs_lookup }, /* lookup */ { &vop_create_desc, kernfs_create }, /* create */ { &vop_mknod_desc, kernfs_mknod }, /* mknod */ { &vop_open_desc, kernfs_open }, /* open */ { &vop_close_desc, kernfs_close }, /* close */ { &vop_access_desc, kernfs_access }, /* access */ { &vop_getattr_desc, kernfs_getattr }, /* getattr */ { &vop_setattr_desc, kernfs_setattr }, /* setattr */ { &vop_read_desc, kernfs_read }, /* read */ { &vop_write_desc, kernfs_write }, /* write */ { &vop_ioctl_desc, kernfs_ioctl }, /* ioctl */ { &vop_select_desc, kernfs_select }, /* select */ { &vop_mmap_desc, kernfs_mmap }, /* mmap */ { &vop_fsync_desc, kernfs_fsync }, /* fsync */ { &vop_seek_desc, kernfs_seek }, /* seek */ { &vop_remove_desc, kernfs_remove }, /* remove */ { &vop_link_desc, kernfs_link }, /* link */ { &vop_rename_desc, kernfs_rename }, /* rename */ { &vop_mkdir_desc, kernfs_mkdir }, /* mkdir */ { &vop_rmdir_desc, kernfs_rmdir }, /* rmdir */ { &vop_symlink_desc, kernfs_symlink }, /* symlink */ { &vop_readdir_desc, kernfs_readdir }, /* readdir */ { &vop_readlink_desc, kernfs_readlink },/* readlink */ { &vop_abortop_desc, kernfs_abortop }, /* abortop */ { &vop_inactive_desc, kernfs_inactive },/* inactive */ { &vop_reclaim_desc, kernfs_reclaim }, /* reclaim */ { &vop_lock_desc, kernfs_lock }, /* lock */ { &vop_unlock_desc, kernfs_unlock }, /* unlock */ { &vop_bmap_desc, kernfs_bmap }, /* bmap */ { &vop_strategy_desc, kernfs_strategy },/* strategy */ { &vop_print_desc, kernfs_print }, /* print */ { &vop_islocked_desc, kernfs_islocked },/* islocked */ { &vop_pathconf_desc, kernfs_pathconf },/* pathconf */ { &vop_advlock_desc, kernfs_advlock }, /* advlock */ { &vop_blkatoff_desc, kernfs_blkatoff },/* blkatoff */ { &vop_valloc_desc, kernfs_valloc }, /* valloc */ { &vop_vfree_desc, kernfs_vfree }, /* vfree */ { &vop_truncate_desc, kernfs_truncate },/* truncate */ { &vop_update_desc, kernfs_update }, /* update */ { &vop_bwrite_desc, kernfs_bwrite }, /* bwrite */ { (struct vnodeop_desc*)NULL, (int(*)())NULL } }; struct vnodeopv_desc kernfs_vnodeop_opv_desc = { &kernfs_vnodeop_p, kernfs_vnodeop_entries };