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36 * @(#)fdesc_vfsops.c 8.4 (Berkeley) 1/21/94
38 * $FreeBSD: src/sys/miscfs/fdesc/fdesc_vfsops.c,v 1.22.2.3 2002/08/23 17:42:39 njl Exp $
39 * $DragonFly: src/sys/vfs/fdesc/fdesc_vfsops.c,v 1.8 2004/08/17 18:57:33 dillon Exp $
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/filedesc.h>
49 #include <sys/kernel.h>
51 #include <sys/malloc.h>
52 #include <sys/mount.h>
54 #include <sys/resourcevar.h>
55 #include <sys/socket.h>
56 #include <sys/vnode.h>
60 extern struct vnodeopv_entry_desc fdesc_vnodeop_entries[];
62 static MALLOC_DEFINE(M_FDESCMNT, "FDESC mount", "FDESC mount structure");
64 static int fdesc_mount (struct mount *mp, char *path, caddr_t data,
65 struct nameidata *ndp, struct thread *td);
66 static int fdesc_unmount (struct mount *mp, int mntflags,
68 static int fdesc_statfs (struct mount *mp, struct statfs *sbp,
72 * Mount the per-process file descriptors (/dev/fd)
75 fdesc_mount(struct mount *mp, char *path, caddr_t data,
76 struct nameidata *ndp, struct thread *td)
79 struct fdescmount *fmp;
84 panic("fdesc_mount: cannot mount as root");
89 if (mp->mnt_flag & MNT_UPDATE)
92 vfs_add_vnodeops(&mp->mnt_vn_ops, fdesc_vnodeop_entries);
94 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp, td);
98 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount),
99 M_FDESCMNT, M_WAITOK); /* XXX */
101 rvp->v_flag |= VROOT;
103 /* XXX -- don't mark as local to work around fts() problems */
104 /*mp->mnt_flag |= MNT_LOCAL;*/
105 mp->mnt_data = (qaddr_t) fmp;
108 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
109 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
110 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
111 bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc"));
112 (void)fdesc_statfs(mp, &mp->mnt_stat, td);
117 fdesc_unmount(struct mount *mp, int mntflags, struct thread *td)
122 if (mntflags & MNT_FORCE)
126 * Clear out buffer cache. I don't think we
127 * ever get anything cached at this level at the
128 * moment, but who knows...
130 * There is 1 extra root vnode reference corresponding
133 if ((error = vflush(mp, 1, flags)) != 0)
137 * Finally, throw away the fdescmount structure
139 free(mp->mnt_data, M_FDESCMNT); /* XXX */
146 fdesc_root(struct mount *mp, struct vnode **vpp)
148 struct thread *td = curthread; /* XXX */
152 * Return locked reference to root.
154 vp = VFSTOFDESC(mp)->f_root;
156 vn_lock(vp, NULL, LK_EXCLUSIVE | LK_RETRY, td);
162 fdesc_statfs(struct mount *mp, struct statfs *sbp, struct thread *td)
164 struct proc *p = td->td_proc;
165 struct filedesc *fdp;
174 * Compute number of free file descriptors.
175 * [ Strange results will ensue if the open file
176 * limit is ever reduced below the current number
179 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur;
181 last = min(fdp->fd_nfiles, lim);
183 for (i = fdp->fd_freefile; i < last; i++)
184 if (fdp->fd_ofiles[i] == NULL)
188 * Adjust for the fact that the fdesc array may not
189 * have been fully allocated yet.
191 if (fdp->fd_nfiles < lim)
192 freefd += (lim - fdp->fd_nfiles);
195 sbp->f_bsize = DEV_BSIZE;
196 sbp->f_iosize = DEV_BSIZE;
197 sbp->f_blocks = 2; /* 1K to keep df happy */
200 sbp->f_files = lim + 1; /* Allow for "." */
201 sbp->f_ffree = freefd; /* See comments above */
202 if (sbp != &mp->mnt_stat) {
203 sbp->f_type = mp->mnt_vfc->vfc_typenum;
204 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
205 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
206 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
211 static struct vfsops fdesc_vfsops = {
228 VFS_SET(fdesc_vfsops, fdesc, VFCF_SYNTHETIC);