/* * Copyright (c) 1993 Jan-Simon Pendry * Copyright (c) 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed 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. * * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95 * * $Id: procfs_subr.c,v 1.18 1997/12/06 04:11:12 sef Exp $ */ #include #include #include #include #include #include static struct pfsnode *pfshead; static int pfsvplock; /* * allocate a pfsnode/vnode pair. the vnode is * referenced, but not locked. * * the pid, pfs_type, and mount point uniquely * identify a pfsnode. the mount point is needed * because someone might mount this filesystem * twice. * * all pfsnodes are maintained on a singly-linked * list. new nodes are only allocated when they cannot * be found on this list. entries on the list are * removed when the vfs reclaim entry is called. * * a single lock is kept for the entire list. this is * needed because the getnewvnode() function can block * waiting for a vnode to become free, in which case there * may be more than one process trying to get the same * vnode. this lock is only taken if we are going to * call getnewvnode, since the kernel itself is single-threaded. * * if an entry is found on the list, then call vget() to * take a reference. this is done because there may be * zero references to it and so it needs to removed from * the vnode free list. */ int procfs_allocvp(mp, vpp, pid, pfs_type) struct mount *mp; struct vnode **vpp; long pid; pfstype pfs_type; { struct proc *p = curproc; /* XXX */ struct pfsnode *pfs; struct vnode *vp; struct pfsnode **pp; int error; loop: for (pfs = pfshead; pfs != 0; pfs = pfs->pfs_next) { vp = PFSTOV(pfs); if (pfs->pfs_pid == pid && pfs->pfs_type == pfs_type && vp->v_mount == mp) { if (vget(vp, 0, p)) goto loop; *vpp = vp; return (0); } } /* * otherwise lock the vp list while we call getnewvnode * since that can block. */ if (pfsvplock & PROCFS_LOCKED) { pfsvplock |= PROCFS_WANT; (void) tsleep((caddr_t) &pfsvplock, PINOD, "pfsavp", 0); goto loop; } pfsvplock |= PROCFS_LOCKED; /* * Do the MALLOC before the getnewvnode since doing so afterward * might cause a bogus v_data pointer to get dereferenced * elsewhere if MALLOC should block. */ MALLOC(pfs, struct pfsnode *, sizeof(struct pfsnode), M_TEMP, M_WAITOK); if (error = getnewvnode(VT_PROCFS, mp, procfs_vnodeop_p, vpp)) { FREE(pfs, M_TEMP); goto out; } vp = *vpp; vp->v_data = pfs; pfs->pfs_next = 0; pfs->pfs_pid = (pid_t) pid; pfs->pfs_type = pfs_type; pfs->pfs_vnode = vp; pfs->pfs_flags = 0; pfs->pfs_lockowner = 0; pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type); switch (pfs_type) { case Proot: /* /proc = dr-xr-xr-x */ pfs->pfs_mode = (VREAD|VEXEC) | (VREAD|VEXEC) >> 3 | (VREAD|VEXEC) >> 6; vp->v_type = VDIR; vp->v_flag = VROOT; break; case Pcurproc: /* /proc/curproc = lr--r--r-- */ pfs->pfs_mode = (VREAD) | (VREAD >> 3) | (VREAD >> 6); vp->v_type = VLNK; break; case Pproc: pfs->pfs_mode = (VREAD|VEXEC) | (VREAD|VEXEC) >> 3 | (VREAD|VEXEC) >> 6; vp->v_type = VDIR; break; case Pfile: case Pmem: pfs->pfs_mode = (VREAD|VWRITE) | (VREAD) >> 3;; vp->v_type = VREG; break; case Pregs: case Pfpregs: pfs->pfs_mode = (VREAD|VWRITE); vp->v_type = VREG; break; case Pctl: case Pnote: case Pnotepg: pfs->pfs_mode = (VWRITE); vp->v_type = VREG; break; case Ptype: case Pmap: case Pstatus: pfs->pfs_mode = (VREAD) | (VREAD >> 3) | (VREAD >> 6); vp->v_type = VREG; break; default: panic("procfs_allocvp"); } /* add to procfs vnode list */ for (pp = &pfshead; *pp; pp = &(*pp)->pfs_next) continue; *pp = pfs; out: pfsvplock &= ~PROCFS_LOCKED; if (pfsvplock & PROCFS_WANT) { pfsvplock &= ~PROCFS_WANT; wakeup((caddr_t) &pfsvplock); } return (error); } int procfs_freevp(vp) struct vnode *vp; { struct pfsnode **pfspp; struct pfsnode *pfs = VTOPFS(vp); for (pfspp = &pfshead; *pfspp != 0; pfspp = &(*pfspp)->pfs_next) { if (*pfspp == pfs) { *pfspp = pfs->pfs_next; break; } } FREE(vp->v_data, M_TEMP); vp->v_data = 0; return (0); } int procfs_rw(ap) struct vop_read_args *ap; { struct vnode *vp = ap->a_vp; struct uio *uio = ap->a_uio; struct proc *curp = uio->uio_procp; struct pfsnode *pfs = VTOPFS(vp); struct proc *p; int rtval; p = PFIND(pfs->pfs_pid); if (p == 0) return (EINVAL); if (p->p_pid == 1 && securelevel > 0 && uio->uio_rw == UIO_WRITE) return (EACCES); while (pfs->pfs_lockowner) { tsleep(&pfs->pfs_lockowner, PRIBIO, "pfslck", 0); } pfs->pfs_lockowner = curproc->p_pid; switch (pfs->pfs_type) { case Pnote: case Pnotepg: rtval = procfs_donote(curp, p, pfs, uio); break; case Pregs: rtval = procfs_doregs(curp, p, pfs, uio); break; case Pfpregs: rtval = procfs_dofpregs(curp, p, pfs, uio); break; case Pctl: rtval = procfs_doctl(curp, p, pfs, uio); break; case Pstatus: rtval = procfs_dostatus(curp, p, pfs, uio); break; case Pmap: rtval = procfs_domap(curp, p, pfs, uio); break; case Pmem: rtval = procfs_domem(curp, p, pfs, uio); break; case Ptype: rtval = procfs_dotype(curp, p, pfs, uio); break; default: rtval = EOPNOTSUPP; break; } pfs->pfs_lockowner = 0; wakeup(&pfs->pfs_lockowner); return rtval; } /* * Get a string from userland into (buf). Strip a trailing * nl character (to allow easy access from the shell). * The buffer should be *buflenp + 1 chars long. vfs_getuserstr * will automatically add a nul char at the end. * * Returns 0 on success or the following errors * * EINVAL: file offset is non-zero. * EMSGSIZE: message is longer than kernel buffer * EFAULT: user i/o buffer is not addressable */ int vfs_getuserstr(uio, buf, buflenp) struct uio *uio; char *buf; int *buflenp; { int xlen; int error; if (uio->uio_offset != 0) return (EINVAL); xlen = *buflenp; /* must be able to read the whole string in one go */ if (xlen < uio->uio_resid) return (EMSGSIZE); xlen = uio->uio_resid; if (error = uiomove(buf, xlen, uio)) return (error); /* allow multiple writes without seeks */ uio->uio_offset = 0; /* cleanup string and remove trailing newline */ buf[xlen] = '\0'; xlen = strlen(buf); if (xlen > 0 && buf[xlen-1] == '\n') buf[--xlen] = '\0'; *buflenp = xlen; return (0); } vfs_namemap_t * vfs_findname(nm, buf, buflen) vfs_namemap_t *nm; char *buf; int buflen; { for (; nm->nm_name; nm++) if (bcmp(buf, nm->nm_name, buflen+1) == 0) return (nm); return (0); } void procfs_exit(struct proc *p) { struct pfsnode *pfs; pid_t pid = p->p_pid; for (pfs = pfshead; pfs ; pfs = pfs->pfs_next) { if (pfs->pfs_pid == pid) vgone(PFSTOV(pfs)); } }