/* $OpenBSD: procfs_vnops.c,v 1.40 2007/06/18 08:30:07 jasper Exp $ */
/* $NetBSD: procfs_vnops.c,v 1.40 1996/03/16 23:52:55 christos Exp $ */
/*
* 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. 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_vnops.c 8.8 (Berkeley) 6/15/94
*/
/*
* procfs vnode interface
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/file.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <sys/dirent.h>
#include <sys/resourcevar.h>
#include <sys/poll.h>
#include <sys/ptrace.h>
#include <sys/stat.h>
#include <uvm/uvm_extern.h> /* for PAGE_SIZE */
#include <machine/reg.h>
#include <miscfs/procfs/procfs.h>
/*
* Vnode Operations.
*
*/
static int procfs_validfile_linux(struct proc *, struct mount *);
/*
* This is a list of the valid names in the
* process-specific sub-directories. It is
* used in procfs_lookup and procfs_readdir
*/
struct proc_target {
u_char pt_type;
u_char pt_namlen;
char *pt_name;
pfstype pt_pfstype;
int (*pt_valid)(struct proc *p, struct mount *mp);
} proc_targets[] = {
#define N(s) sizeof(s)-1, s
/* name type validp */
{ DT_DIR, N("."), Pproc, NULL },
{ DT_DIR, N(".."), Proot, NULL },
{ DT_REG, N("file"), Pfile, procfs_validfile },
{ DT_REG, N("mem"), Pmem, NULL },
{ DT_REG, N("ctl"), Pctl, NULL },
{ DT_REG, N("status"), Pstatus, NULL },
{ DT_REG, N("note"), Pnote, NULL },
{ DT_REG, N("notepg"), Pnotepg, NULL },
{ DT_REG, N("cmdline"), Pcmdline, NULL },
{ DT_REG, N("exe"), Pfile, procfs_validfile_linux },
#undef N
};
static int nproc_targets = sizeof(proc_targets) / sizeof(proc_targets[0]);
/*
* List of files in the root directory. Note: the validate function
* will be called with p == NULL for these
*/
struct proc_target proc_root_targets[] = {
#define N(s) sizeof(s)-1, s
/* name type validp */
{ DT_REG, N("meminfo"), Pmeminfo, procfs_validfile_linux },
{ DT_REG, N("cpuinfo"), Pcpuinfo, procfs_validfile_linux },
#undef N
};
static int nproc_root_targets =
sizeof(proc_root_targets) / sizeof(proc_root_targets[0]);
static pid_t atopid(const char *, u_int);
/*
* Prototypes for procfs vnode ops
*/
int procfs_badop(void *);
int procfs_lookup(void *);
#define procfs_create procfs_badop
#define procfs_mknod procfs_badop
int procfs_open(void *);
int procfs_close(void *);
int procfs_access(void *);
int procfs_getattr(void *);
int procfs_setattr(void *);
#define procfs_read procfs_rw
#define procfs_write procfs_rw
int procfs_ioctl(void *);
#define procfs_fsync procfs_badop
#define procfs_remove procfs_badop
int procfs_link(void *);
#define procfs_rename procfs_badop
#define procfs_mkdir procfs_badop
#define procfs_rmdir procfs_badop
int procfs_symlink(void *);
int procfs_readdir(void *);
int procfs_readlink(void *);
int procfs_inactive(void *);
int procfs_reclaim(void *);
#define procfs_lock nullop
#define procfs_unlock nullop
int procfs_bmap(void *);
#define procfs_strategy procfs_badop
int procfs_print(void *);
int procfs_pathconf(void *);
#define procfs_islocked nullop
#define procfs_advlock procfs_badop
static pid_t atopid(const char *, u_int);
/*
* procfs vnode operations.
*/
int (**procfs_vnodeop_p)(void *);
struct vnodeopv_entry_desc procfs_vnodeop_entries[] = {
{ &vop_default_desc, vn_default_error },
{ &vop_lookup_desc, procfs_lookup }, /* lookup */
{ &vop_create_desc, procfs_create }, /* create */
{ &vop_mknod_desc, procfs_mknod }, /* mknod */
{ &vop_open_desc, procfs_open }, /* open */
{ &vop_close_desc, procfs_close }, /* close */
{ &vop_access_desc, procfs_access }, /* access */
{ &vop_getattr_desc, procfs_getattr }, /* getattr */
{ &vop_setattr_desc, procfs_setattr }, /* setattr */
{ &vop_read_desc, procfs_read }, /* read */
{ &vop_write_desc, procfs_write }, /* write */
{ &vop_ioctl_desc, procfs_ioctl }, /* ioctl */
{ &vop_poll_desc, procfs_poll }, /* poll */
{ &vop_fsync_desc, procfs_fsync }, /* fsync */
{ &vop_remove_desc, procfs_remove }, /* remove */
{ &vop_link_desc, procfs_link }, /* link */
{ &vop_rename_desc, procfs_rename }, /* rename */
{ &vop_mkdir_desc, procfs_mkdir }, /* mkdir */
{ &vop_rmdir_desc, procfs_rmdir }, /* rmdir */
{ &vop_symlink_desc, procfs_symlink }, /* symlink */
{ &vop_readdir_desc, procfs_readdir }, /* readdir */
{ &vop_readlink_desc, procfs_readlink }, /* readlink */
{ &vop_abortop_desc, vop_generic_abortop }, /* abortop */
{ &vop_inactive_desc, procfs_inactive }, /* inactive */
{ &vop_reclaim_desc, procfs_reclaim }, /* reclaim */
{ &vop_lock_desc, procfs_lock }, /* lock */
{ &vop_unlock_desc, procfs_unlock }, /* unlock */
{ &vop_bmap_desc, procfs_bmap }, /* bmap */
{ &vop_strategy_desc, procfs_strategy }, /* strategy */
{ &vop_print_desc, procfs_print }, /* print */
{ &vop_islocked_desc, procfs_islocked }, /* islocked */
{ &vop_pathconf_desc, procfs_pathconf }, /* pathconf */
{ &vop_advlock_desc, procfs_advlock }, /* advlock */
{ NULL, NULL }
};
struct vnodeopv_desc procfs_vnodeop_opv_desc =
{ &procfs_vnodeop_p, procfs_vnodeop_entries };
/*
* set things up for doing i/o on
* the pfsnode (vp). (vp) is locked
* on entry, and should be left locked
* on exit.
*
* for procfs we don't need to do anything
* in particular for i/o. all that is done
* is to support exclusive open on process
* memory images.
*/
int
procfs_open(void *v)
{
struct vop_open_args *ap = v;
struct pfsnode *pfs = VTOPFS(ap->a_vp);
struct proc *p1 = ap->a_p; /* tracer */
struct proc *p2; /* traced */
int error;
if ((p2 = pfind(pfs->pfs_pid)) == 0)
return (ENOENT); /* was ESRCH, jsp */
switch (pfs->pfs_type) {
case Pmem:
if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) ||
((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE)))
return (EBUSY);
if ((error = process_checkioperm(p1, p2)) != 0)
return (error);
if (ap->a_mode & FWRITE)
pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL);
return (0);
default:
break;
}
return (0);
}
/*
* close the pfsnode (vp) after doing i/o.
* (vp) is not locked on entry or exit.
*
* nothing to do for procfs other than undo
* any exclusive open flag (see _open above).
*/
int
procfs_close(void *v)
{
struct vop_close_args *ap = v;
struct pfsnode *pfs = VTOPFS(ap->a_vp);
switch (pfs->pfs_type) {
case Pmem:
if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL))
pfs->pfs_flags &= ~(FWRITE|O_EXCL);
break;
case Pctl:
case Pstatus:
case Pnotepg:
case Pnote:
case Proot:
case Pcurproc:
case Pself:
case Pproc:
case Pfile:
case Pregs:
case Pfpregs:
case Pcmdline:
case Pmeminfo:
case Pcpuinfo:
break;
}
return (0);
}
/*
* do an ioctl operation on pfsnode (vp).
* (vp) is not locked on entry or exit.
*/
/*ARGSUSED*/
int
procfs_ioctl(void *v)
{
return (ENOTTY);
}
/*
* do block mapping for pfsnode (vp).
* since we don't use the buffer cache
* for procfs this function should never
* be called. in any case, it's not clear
* what part of the kernel ever makes use
* of this function. for sanity, this is the
* usual no-op bmap, although returning
* (EIO) would be a reasonable alternative.
*/
int
procfs_bmap(void *v)
{
struct vop_bmap_args *ap = v;
if (ap->a_vpp != NULL)
*ap->a_vpp = ap->a_vp;
if (ap->a_bnp != NULL)
*ap->a_bnp = ap->a_bn;
return (0);
}
/*
* _inactive is called when the pfsnode
* is vrele'd and the reference count goes
* to zero. (vp) will be on the vnode free
* list, so to get it back vget() must be
* used.
*
* for procfs, check if the process is still
* alive and if it isn't then just throw away
* the vnode by calling vgone(). this may
* be overkill and a waste of time since the
* chances are that the process will still be
* there and pfind is not free.
*
* (vp) is not locked on entry or exit.
*/
int
procfs_inactive(void *v)
{
struct vop_inactive_args *ap = v;
struct vnode *vp = ap->a_vp;
struct pfsnode *pfs = VTOPFS(vp);
if (pfind(pfs->pfs_pid) == NULL && !(vp->v_flag & VXLOCK))
vgone(vp);
return (0);
}
/*
* _reclaim is called when getnewvnode()
* wants to make use of an entry on the vnode
* free list. at this time the filesystem needs
* to free any private data and remove the node
* from any private lists.
*/
int
procfs_reclaim(void *v)
{
struct vop_reclaim_args *ap = v;
return (procfs_freevp(ap->a_vp));
}
/*
* Return POSIX pathconf information applicable to special devices.
*/
int
procfs_pathconf(void *v)
{
struct vop_pathconf_args *ap = v;
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 is used for debugging.
* just print a readable description
* of (vp).
*/
int
procfs_print(void *v)
{
struct vop_print_args *ap = v;
struct pfsnode *pfs = VTOPFS(ap->a_vp);
printf("tag VT_PROCFS, type %d, pid %d, mode %x, flags %lx\n",
pfs->pfs_type, pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags);
return 0;
}
int
procfs_link(void *v)
{
struct vop_link_args *ap = v;
VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
vput(ap->a_dvp);
return (EROFS);
}
int
procfs_symlink(void *v)
{
struct vop_symlink_args *ap = v;
VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
vput(ap->a_dvp);
return (EROFS);
}
/*
* generic entry point for unsupported operations
*/
/*ARGSUSED*/
int
procfs_badop(void *v)
{
return (EIO);
}
/*
* Invent attributes for pfsnode (vp) and store
* them in (vap).
* Directories lengths are returned as zero since
* any real length would require the genuine size
* to be computed, and nothing cares anyway.
*
* this is relatively minimal for procfs.
*/
int
procfs_getattr(void *v)
{
struct vop_getattr_args *ap = v;
struct pfsnode *pfs = VTOPFS(ap->a_vp);
struct vattr *vap = ap->a_vap;
struct proc *procp;
int error;
/* first check the process still exists */
switch (pfs->pfs_type) {
case Proot:
case Pcurproc:
case Pcpuinfo:
case Pmeminfo:
procp = 0;
break;
default:
procp = pfind(pfs->pfs_pid);
if (procp == 0)
return (ENOENT);
}
error = 0;
/* start by zeroing out the attributes */
VATTR_NULL(vap);
/* next do all the common fields */
vap->va_type = ap->a_vp->v_type;
vap->va_mode = pfs->pfs_mode;
vap->va_fileid = pfs->pfs_fileno;
vap->va_flags = 0;
vap->va_blocksize = PAGE_SIZE;
vap->va_bytes = vap->va_size = 0;
/*
* Make all times be current TOD.
* It would be possible to get the process start
* time from the p_stat structure, but there's
* no "file creation" time stamp anyway, and the
* p_stat structure is not addressible if u. gets
* swapped out for that process.
*/
getnanotime(&vap->va_ctime);
vap->va_atime = vap->va_mtime = vap->va_ctime;
switch (pfs->pfs_type) {
case Pregs:
case Pfpregs:
#ifndef PTRACE
break;
#endif
case Pmem:
/*
* If the process has exercised some setuid or setgid
* privilege, then rip away read/write permission so
* that only root can gain access.
*/
if (procp->p_flag & P_SUGID)
vap->va_mode &= ~(S_IRUSR|S_IWUSR);
/* FALLTHROUGH */
case Pctl:
case Pstatus:
case Pnote:
case Pnotepg:
case Pcmdline:
vap->va_nlink = 1;
vap->va_uid = procp->p_ucred->cr_uid;
vap->va_gid = procp->p_ucred->cr_gid;
break;
case Pmeminfo:
case Pcpuinfo:
vap->va_nlink = 1;
vap->va_uid = vap->va_gid = 0;
break;
case Pproc:
case Pfile:
case Proot:
case Pcurproc:
case Pself:
break;
}
/*
* now do the object specific fields
*
* The size could be set from struct reg, but it's hardly
* worth the trouble, and it puts some (potentially) machine
* dependent data into this machine-independent code. If it
* becomes important then this function should break out into
* a per-file stat function in the corresponding .c file.
*/
switch (pfs->pfs_type) {
case Proot:
/*
* Set nlink to 1 to tell fts(3) we don't actually know.
*/
vap->va_nlink = 1;
vap->va_uid = 0;
vap->va_gid = 0;
vap->va_size = vap->va_bytes = DEV_BSIZE;
break;
case Pcurproc: {
char buf[16]; /* should be enough */
int len;
len = snprintf(buf, sizeof buf, "%ld", (long)curproc->p_pid);
if (len == -1 || len >= sizeof buf) {
error = EINVAL;
break;
}
vap->va_nlink = 1;
vap->va_uid = 0;
vap->va_gid = 0;
vap->va_size = vap->va_bytes = len;
break;
}
case Pself:
vap->va_nlink = 1;
vap->va_uid = 0;
vap->va_gid = 0;
vap->va_size = vap->va_bytes = sizeof("curproc");
break;
case Pproc:
vap->va_nlink = 2;
vap->va_uid = procp->p_ucred->cr_uid;
vap->va_gid = procp->p_ucred->cr_gid;
vap->va_size = vap->va_bytes = DEV_BSIZE;
break;
case Pfile:
error = EOPNOTSUPP;
break;
case Pmem:
vap->va_bytes = vap->va_size =
ctob(procp->p_vmspace->vm_tsize +
procp->p_vmspace->vm_dsize +
procp->p_vmspace->vm_ssize);
break;
case Pregs:
#ifdef PTRACE
vap->va_bytes = vap->va_size = sizeof(struct reg);
#endif
break;
case Pfpregs:
#if defined(PT_GETFPREGS) || defined(PT_SETFPREGS)
#ifdef PTRACE
vap->va_bytes = vap->va_size = sizeof(struct fpreg);
#endif
#endif
break;
case Pctl:
case Pstatus:
case Pnote:
case Pnotepg:
case Pcmdline:
case Pmeminfo:
case Pcpuinfo:
vap->va_bytes = vap->va_size = 0;
break;
#ifdef DIAGNOSTIC
default:
panic("procfs_getattr");
#endif
}
return (error);
}
/*ARGSUSED*/
int
procfs_setattr(void *v)
{
/*
* just fake out attribute setting
* it's not good to generate an error
* return, otherwise things like creat()
* will fail when they try to set the
* file length to 0. worse, this means
* that echo $note > /proc/$pid/note will fail.
*/
return (0);
}
/*
* implement access checking.
*
* actually, the check for super-user is slightly
* broken since it will allow read access to write-only
* objects. this doesn't cause any particular trouble
* but does mean that the i/o entry points need to check
* that the operation really does make sense.
*/
int
procfs_access(void *v)
{
struct vop_access_args *ap = v;
struct vattr va;
int error;
if ((error = VOP_GETATTR(ap->a_vp, &va, ap->a_cred, ap->a_p)) != 0)
return (error);
return (vaccess(va.va_mode, va.va_uid, va.va_gid, ap->a_mode,
ap->a_cred));
}
/*
* lookup. this is incredibly complicated in the
* general case, however for most pseudo-filesystems
* very little needs to be done.
*
* unless you want to get a migraine, just make sure your
* filesystem doesn't do any locking of its own. otherwise
* read and inwardly digest ufs_lookup().
*/
int
procfs_lookup(void *v)
{
struct vop_lookup_args *ap = v;
struct componentname *cnp = ap->a_cnp;
struct vnode **vpp = ap->a_vpp;
struct vnode *dvp = ap->a_dvp;
char *pname = cnp->cn_nameptr;
struct proc *curp = curproc;
struct proc_target *pt;
struct vnode *fvp;
pid_t pid;
struct pfsnode *pfs;
struct proc *p = NULL;
int i, error, wantpunlock, iscurproc = 0, isself = 0;
*vpp = NULL;
cnp->cn_flags &= ~PDIRUNLOCK;
if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)
return (EROFS);
if (cnp->cn_namelen == 1 && *pname == '.') {
*vpp = dvp;
VREF(dvp);
return (0);
}
wantpunlock = (~cnp->cn_flags & (LOCKPARENT | ISLASTCN));
pfs = VTOPFS(dvp);
switch (pfs->pfs_type) {
case Proot:
if (cnp->cn_flags & ISDOTDOT)
return (EIO);
iscurproc = CNEQ(cnp, "curproc", 7);
isself = CNEQ(cnp, "self", 4);
if (iscurproc || isself) {
error = procfs_allocvp(dvp->v_mount, vpp, 0,
iscurproc ? Pcurproc : Pself);
if ((error == 0) && (wantpunlock)) {
VOP_UNLOCK(dvp, 0, curp);
cnp->cn_flags |= PDIRUNLOCK;
}
return (error);
}
for (i = 0; i < nproc_root_targets; i++) {
pt = &proc_root_targets[i];
if (cnp->cn_namelen == pt->pt_namlen &&
memcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 &&
(pt->pt_valid == NULL ||
(*pt->pt_valid)(p, dvp->v_mount)))
break;
}
if (i != nproc_root_targets) {
error = procfs_allocvp(dvp->v_mount, vpp, 0,
pt->pt_pfstype);
if ((error == 0) && (wantpunlock)) {
VOP_UNLOCK(dvp, 0, curp);
cnp->cn_flags |= PDIRUNLOCK;
}
return (error);
}
pid = atopid(pname, cnp->cn_namelen);
if (pid == NO_PID)
break;
p = pfind(pid);
if (p == 0)
break;
error = procfs_allocvp(dvp->v_mount, vpp, pid, Pproc);
if ((error == 0) && wantpunlock) {
VOP_UNLOCK(dvp, 0, curp);
cnp->cn_flags |= PDIRUNLOCK;
}
return (error);
case Pproc:
/*
* do the .. dance. We unlock the directory, and then
* get the root dir. That will automatically return ..
* locked. Then if the caller wanted dvp locked, we
* re-lock.
*/
if (cnp->cn_flags & ISDOTDOT) {
VOP_UNLOCK(dvp, 0, p);
cnp->cn_flags |= PDIRUNLOCK;
error = procfs_root(dvp->v_mount, vpp);
if ((error == 0) && (wantpunlock == 0) &&
((error = vn_lock(dvp, LK_EXCLUSIVE, curp)) == 0))
cnp->cn_flags &= ~PDIRUNLOCK;
return (error);
}
p = pfind(pfs->pfs_pid);
if (p == 0)
break;
for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) {
if (cnp->cn_namelen == pt->pt_namlen &&
bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 &&
(pt->pt_valid == NULL ||
(*pt->pt_valid)(p, dvp->v_mount)))
goto found;
}
break;
found:
if (pt->pt_pfstype == Pfile) {
fvp = p->p_textvp;
/* We already checked that it exists. */
VREF(fvp);
vn_lock(fvp, LK_EXCLUSIVE | LK_RETRY, curp);
if (wantpunlock) {
VOP_UNLOCK(dvp, 0, curp);
cnp->cn_flags |= PDIRUNLOCK;
}
*vpp = fvp;
return (0);
}
error = procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid,
pt->pt_pfstype);
if ((error == 0) && (wantpunlock)) {
VOP_UNLOCK(dvp, 0, curp);
cnp->cn_flags |= PDIRUNLOCK;
}
return (error);
default:
return (ENOTDIR);
}
return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS);
}
int
procfs_validfile(struct proc *p, struct mount *mp)
{
return (p->p_textvp != NULLVP);
}
int
procfs_validfile_linux(struct proc *p, struct mount *mp)
{
int flags;
flags = VFSTOPROC(mp)->pmnt_flags;
return ((flags & PROCFSMNT_LINUXCOMPAT) &&
(p == NULL || procfs_validfile(p, mp)));
}
/*
* readdir returns directory entries from pfsnode (vp).
*
* the strategy here with procfs is to generate a single
* directory entry at a time (struct dirent) and then
* copy that out to userland using uiomove. a more efficent
* though more complex implementation, would try to minimize
* the number of calls to uiomove(). for procfs, this is
* hardly worth the added code complexity.
*
* this should just be done through read()
*/
int
procfs_readdir(void *v)
{
struct vop_readdir_args *ap = v;
struct uio *uio = ap->a_uio;
struct dirent d;
struct pfsnode *pfs;
struct vnode *vp;
int i;
int error;
vp = ap->a_vp;
pfs = VTOPFS(vp);
if (uio->uio_resid < UIO_MX)
return (EINVAL);
error = 0;
i = uio->uio_offset;
if (i < 0)
return (EINVAL);
bzero(&d, UIO_MX);
d.d_reclen = UIO_MX;
switch (pfs->pfs_type) {
/*
* this is for the process-specific sub-directories.
* all that is needed to is copy out all the entries
* from the procent[] table (top of this file).
*/
case Pproc: {
struct proc *p;
struct proc_target *pt;
p = pfind(pfs->pfs_pid);
if (p == NULL)
break;
for (pt = &proc_targets[i];
uio->uio_resid >= UIO_MX && i < nproc_targets; pt++, i++) {
if (pt->pt_valid &&
(*pt->pt_valid)(p, vp->v_mount) == 0)
continue;
d.d_fileno = PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype);
d.d_namlen = pt->pt_namlen;
bcopy(pt->pt_name, d.d_name, pt->pt_namlen + 1);
d.d_type = pt->pt_type;
if ((error = uiomove(&d, UIO_MX, uio)) != 0)
break;
}
break;
}
/*
* this is for the root of the procfs filesystem
* what is needed is a special entry for "curproc"
* followed by an entry for each process on allproc
#ifdef PROCFS_ZOMBIE
* and zombproc.
#endif
*/
case Proot: {
#ifdef PROCFS_ZOMBIE
int doingzomb = 0;
#endif
int pcnt = i;
volatile struct proc *p = LIST_FIRST(&allproc);
if (pcnt > 3)
pcnt = 3;
#ifdef PROCFS_ZOMBIE
again:
#endif
for (; p && uio->uio_resid >= UIO_MX; i++, pcnt++) {
switch (i) {
case 0: /* `.' */
case 1: /* `..' */
d.d_fileno = PROCFS_FILENO(0, Proot);
d.d_namlen = i + 1;
bcopy("..", d.d_name, d.d_namlen);
d.d_name[i + 1] = '\0';
d.d_type = DT_DIR;
break;
case 2:
d.d_fileno = PROCFS_FILENO(0, Pcurproc);
d.d_namlen = 7;
bcopy("curproc", d.d_name, 8);
d.d_type = DT_LNK;
break;
case 3:
d.d_fileno = PROCFS_FILENO(0, Pself);
d.d_namlen = 4;
bcopy("self", d.d_name, 5);
d.d_type = DT_LNK;
break;
case 4:
if (VFSTOPROC(vp->v_mount)->pmnt_flags &
PROCFSMNT_LINUXCOMPAT) {
d.d_fileno = PROCFS_FILENO(0, Pcpuinfo);
d.d_namlen = 7;
bcopy("cpuinfo", d.d_name, 8);
d.d_type = DT_REG;
break;
}
/* fall through */
case 5:
if (VFSTOPROC(vp->v_mount)->pmnt_flags &
PROCFSMNT_LINUXCOMPAT) {
d.d_fileno = PROCFS_FILENO(0, Pmeminfo);
d.d_namlen = 7;
bcopy("meminfo", d.d_name, 8);
d.d_type = DT_REG;
break;
}
/* fall through */
default:
while (pcnt < i) {
pcnt++;
p = LIST_NEXT(p, p_list);
if (!p)
goto done;
}
d.d_fileno = PROCFS_FILENO(p->p_pid, Pproc);
d.d_namlen = snprintf(d.d_name, sizeof(d.d_name),
"%ld", (long)p->p_pid);
d.d_type = DT_REG;
p = LIST_NEXT(p, p_list);
break;
}
if ((error = uiomove(&d, UIO_MX, uio)) != 0)
break;
}
done:
#ifdef PROCFS_ZOMBIE
if (p == 0 && doingzomb == 0) {
doingzomb = 1;
p = LIST_FIRST(&zombproc);
goto again;
}
#endif
break;
}
default:
error = ENOTDIR;
break;
}
uio->uio_offset = i;
return (error);
}
/*
* readlink reads the link of `curproc'
*/
int
procfs_readlink(void *v)
{
struct vop_readlink_args *ap = v;
char buf[16]; /* should be enough */
int len;
if (VTOPFS(ap->a_vp)->pfs_fileno == PROCFS_FILENO(0, Pcurproc))
len = snprintf(buf, sizeof buf, "%ld", (long)curproc->p_pid);
else if (VTOPFS(ap->a_vp)->pfs_fileno == PROCFS_FILENO(0, Pself))
len = strlcpy(buf, "curproc", sizeof buf);
else
return (EINVAL);
if (len == -1 || len >= sizeof buf)
return (EINVAL);
return (uiomove(buf, len, ap->a_uio));
}
/*
* convert decimal ascii to pid_t
*/
static pid_t
atopid(const char *b, u_int len)
{
pid_t p = 0;
while (len--) {
char c = *b++;
if (c < '0' || c > '9')
return (NO_PID);
p = 10 * p + (c - '0');
if (p > PID_MAX)
return (NO_PID);
}
return (p);
}
int
procfs_poll(void *v)
{
struct vop_poll_args *ap = v;
return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
}
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