diff options
Diffstat (limited to 'sys/fs/fdescfs/fdesc_vfsops.c')
| -rw-r--r-- | sys/fs/fdescfs/fdesc_vfsops.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/sys/fs/fdescfs/fdesc_vfsops.c b/sys/fs/fdescfs/fdesc_vfsops.c new file mode 100644 index 0000000..0105ff7 --- /dev/null +++ b/sys/fs/fdescfs/fdesc_vfsops.c @@ -0,0 +1,234 @@ +/* + * 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 <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/proc.h> +#include <sys/resourcevar.h> +#include <sys/filedesc.h> +#include <sys/vnode.h> +#include <sys/mount.h> +#include <sys/malloc.h> +#include <miscfs/fdesc/fdesc.h> + +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_stdcheckexp, + vfs_stdvptofh, + fdesc_init, + vfs_stduninit, + vfs_stdextattrctl, +}; + +VFS_SET(fdesc_vfsops, fdesc, VFCF_SYNTHETIC); |
