/* * Copyright (c) 1992, 1993, 1995 * 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. * * @(#)fdesc_vfsops.c 8.4 (Berkeley) 1/21/94 * * $FreeBSD$ */ /* * /dev/fd Filesystem */ #include #include #include #include #include #include #include #include #include #include static MALLOC_DEFINE(M_FDESCMNT, "FDESC mount", "FDESC mount structure"); static int fdesc_mount __P((struct mount *mp, char *path, caddr_t data, struct nameidata *ndp, struct proc *p)); static int fdesc_unmount __P((struct mount *mp, int mntflags, struct proc *p)); static int fdesc_statfs __P((struct mount *mp, struct statfs *sbp, struct proc *p)); /* * Mount the per-process file descriptors (/dev/fd) */ static int fdesc_mount(mp, path, data, ndp, p) struct mount *mp; char *path; caddr_t data; struct nameidata *ndp; struct proc *p; { int error = 0; u_int size; struct fdescmount *fmp; struct vnode *rvp; /* * Update is a no-op */ if (mp->mnt_flag & MNT_UPDATE) return (EOPNOTSUPP); error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp); if (error) return (error); MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount), M_FDESCMNT, M_WAITOK); /* XXX */ rvp->v_type = VDIR; rvp->v_flag |= VROOT; fmp->f_root = rvp; /* XXX -- don't mark as local to work around fts() problems */ /*mp->mnt_flag |= MNT_LOCAL;*/ mp->mnt_data = (qaddr_t) fmp; vfs_getnewfsid(mp); (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size); bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size); bzero(mp->mnt_stat.f_mntfromname, MNAMELEN); bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc")); (void)fdesc_statfs(mp, &mp->mnt_stat, p); return (0); } static int fdesc_unmount(mp, mntflags, p) struct mount *mp; int mntflags; struct proc *p; { int error; int flags = 0; struct vnode *rootvp = VFSTOFDESC(mp)->f_root; if (mntflags & MNT_FORCE) flags |= FORCECLOSE; /* * Clear out buffer cache. I don't think we * ever get anything cached at this level at the * moment, but who knows... */ if (rootvp->v_usecount > 1) return (EBUSY); if ((error = vflush(mp, rootvp, flags)) != 0) return (error); /* * Release reference on underlying root vnode */ vrele(rootvp); /* * And blow it away for future re-use */ vgone(rootvp); /* * Finally, throw away the fdescmount structure */ free(mp->mnt_data, M_FDESCMNT); /* XXX */ mp->mnt_data = 0; return (0); } int fdesc_root(mp, vpp) struct mount *mp; struct vnode **vpp; { struct proc *p = curproc; /* XXX */ struct vnode *vp; /* * Return locked reference to root. */ vp = VFSTOFDESC(mp)->f_root; VREF(vp); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); *vpp = vp; return (0); } static int fdesc_statfs(mp, sbp, p) struct mount *mp; struct statfs *sbp; struct proc *p; { struct filedesc *fdp; int lim; int i; int last; int freefd; /* * Compute number of free file descriptors. * [ Strange results will ensue if the open file * limit is ever reduced below the current number * of open files... ] */ lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur; fdp = p->p_fd; last = min(fdp->fd_nfiles, lim); freefd = 0; for (i = fdp->fd_freefile; i < last; i++) if (fdp->fd_ofiles[i] == NULL) freefd++; /* * Adjust for the fact that the fdesc array may not * have been fully allocated yet. */ if (fdp->fd_nfiles < lim) freefd += (lim - fdp->fd_nfiles); sbp->f_flags = 0; sbp->f_bsize = DEV_BSIZE; sbp->f_iosize = DEV_BSIZE; sbp->f_blocks = 2; /* 1K to keep df happy */ sbp->f_bfree = 0; sbp->f_bavail = 0; sbp->f_files = lim + 1; /* Allow for "." */ sbp->f_ffree = freefd; /* See comments above */ if (sbp != &mp->mnt_stat) { sbp->f_type = mp->mnt_vfc->vfc_typenum; bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid)); bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN); bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN); } return (0); } static struct vfsops fdesc_vfsops = { fdesc_mount, vfs_stdstart, fdesc_unmount, fdesc_root, vfs_stdquotactl, fdesc_statfs, vfs_stdsync, vfs_stdvget, vfs_stdfhtovp, vfs_stdvptofh, fdesc_init, }; VFS_SET(fdesc_vfsops, fdesc, VFCF_SYNTHETIC);