privcmd.c revision a576ab5b6e08c47732b3dedca9eaa8a8cbb85720
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/types.h>
#include <sys/file.h>
#include <sys/errno.h>
#include <sys/open.h>
#include <sys/cred.h>
#include <sys/conf.h>
#include <sys/stat.h>
#include <sys/modctl.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/vmsystm.h>
#include <sys/sdt.h>
#include <sys/hypervisor.h>
#include <sys/xen_errno.h>
#include <vm/hat_i86.h>
#include <vm/hat_pte.h>
#include <vm/seg_mf.h>
#include <xen/sys/privcmd.h>
#include <sys/privcmd_impl.h>
static dev_info_t *privcmd_devi;
/*ARGSUSED*/
static int
privcmd_getinfo(dev_info_t *devi, ddi_info_cmd_t cmd, void *arg, void **result)
{
switch (cmd) {
case DDI_INFO_DEVT2DEVINFO:
case DDI_INFO_DEVT2INSTANCE:
break;
default:
return (DDI_FAILURE);
}
switch (getminor((dev_t)arg)) {
case PRIVCMD_MINOR:
break;
default:
return (DDI_FAILURE);
}
if (cmd == DDI_INFO_DEVT2INSTANCE)
*result = 0;
else
*result = privcmd_devi;
return (DDI_SUCCESS);
}
static int
privcmd_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
{
if (cmd != DDI_ATTACH)
return (DDI_FAILURE);
if (ddi_create_minor_node(devi, PRIVCMD_NODE,
S_IFCHR, PRIVCMD_MINOR, DDI_PSEUDO, 0) != DDI_SUCCESS)
return (DDI_FAILURE);
privcmd_devi = devi;
ddi_report_dev(devi);
return (DDI_SUCCESS);
}
static int
privcmd_detach(dev_info_t *devi, ddi_detach_cmd_t cmd)
{
if (cmd != DDI_DETACH)
return (DDI_FAILURE);
ddi_remove_minor_node(devi, NULL);
privcmd_devi = NULL;
return (DDI_SUCCESS);
}
/*ARGSUSED1*/
static int
privcmd_open(dev_t *dev, int flag, int otyp, cred_t *cr)
{
return (getminor(*dev) == PRIVCMD_MINOR ? 0 : ENXIO);
}
/*
* Map a contiguous set of machine frames in a foreign domain.
* Used in the following way:
*
* privcmd_mmap_t p;
* privcmd_mmap_entry_t e;
*
* addr = mmap(NULL, size, prot, MAP_SHARED, fd, 0);
* p.num = number of privcmd_mmap_entry_t's
* p.dom = domid;
* p.entry = &e;
* e.va = addr;
* e.mfn = mfn;
* e.npages = btopr(size);
* ioctl(fd, IOCTL_PRIVCMD_MMAP, &p);
*/
/*ARGSUSED2*/
int
do_privcmd_mmap(void *uarg, int mode, cred_t *cr)
{
privcmd_mmap_t __mmapcmd, *mmc = &__mmapcmd;
privcmd_mmap_entry_t *umme;
struct as *as = curproc->p_as;
struct seg *seg;
int i, error = 0;
if (ddi_copyin(uarg, mmc, sizeof (*mmc), mode))
return (EFAULT);
DTRACE_XPV3(mmap__start, domid_t, mmc->dom, int, mmc->num,
privcmd_mmap_entry_t *, mmc->entry);
if (mmc->dom == DOMID_SELF) {
error = ENOTSUP; /* Too paranoid? */
goto done;
}
for (umme = mmc->entry, i = 0; i < mmc->num; i++, umme++) {
privcmd_mmap_entry_t __mmapent, *mme = &__mmapent;
caddr_t addr;
if (ddi_copyin(umme, mme, sizeof (*mme), mode)) {
error = EFAULT;
break;
}
DTRACE_XPV3(mmap__entry, ulong_t, mme->va, ulong_t, mme->mfn,
ulong_t, mme->npages);
if (mme->mfn == MFN_INVALID) {
error = EINVAL;
break;
}
addr = (caddr_t)mme->va;
/*
* Find the segment we want to mess with, then add
* the mfn range to the segment.
*/
AS_LOCK_ENTER(as, &as->a_lock, RW_READER);
if ((seg = as_findseg(as, addr, 0)) == NULL ||
addr + mmu_ptob(mme->npages) > seg->s_base + seg->s_size)
error = EINVAL;
else
error = segmf_add_mfns(seg, addr,
mme->mfn, mme->npages, mmc->dom);
AS_LOCK_EXIT(as, &as->a_lock);
if (error != 0)
break;
}
done:
DTRACE_XPV1(mmap__end, int, error);
return (error);
}
/*
* Set up the address range to map to an array of mfns in
* a foreign domain. Used in the following way:
*
* privcmd_mmap_batch_t p;
*
* addr = mmap(NULL, size, prot, MAP_SHARED, fd, 0);
* p.num = number of pages
* p.dom = domid
* p.addr = addr;
* p.arr = array of mfns, indexed 0 .. p.num - 1
* ioctl(fd, IOCTL_PRIVCMD_MMAPBATCH, &p);
*/
/*ARGSUSED2*/
static int
do_privcmd_mmapbatch(void *uarg, int mode, cred_t *cr)
{
privcmd_mmapbatch_t __mmapbatch, *mmb = &__mmapbatch;
struct as *as = curproc->p_as;
struct seg *seg;
int i, error = 0;
caddr_t addr;
ulong_t *ulp;
if (ddi_copyin(uarg, mmb, sizeof (*mmb), mode))
return (EFAULT);
DTRACE_XPV3(mmapbatch__start, domid_t, mmb->dom, int, mmb->num,
caddr_t, mmb->addr);
addr = (caddr_t)mmb->addr;
AS_LOCK_ENTER(as, &as->a_lock, RW_READER);
if ((seg = as_findseg(as, addr, 0)) == NULL ||
addr + ptob(mmb->num) > seg->s_base + seg->s_size) {
error = EINVAL;
goto done;
}
for (i = 0, ulp = mmb->arr;
i < mmb->num; i++, addr += PAGESIZE, ulp++) {
mfn_t mfn;
if (fulword(ulp, &mfn) != 0) {
error = EFAULT;
break;
}
if (mfn == MFN_INVALID) {
/*
* This mfn is invalid and should not be added to
* segmf, as we'd only cause an immediate EFAULT when
* we tried to fault it in.
*/
mfn |= XEN_DOMCTL_PFINFO_XTAB;
continue;
}
if (segmf_add_mfns(seg, addr, mfn, 1, mmb->dom) == 0)
continue;
/*
* Tell the process that this MFN could not be mapped, so it
* won't later try to access it.
*/
mfn |= XEN_DOMCTL_PFINFO_XTAB;
if (sulword(ulp, mfn) != 0) {
error = EFAULT;
break;
}
}
done:
AS_LOCK_EXIT(as, &as->a_lock);
DTRACE_XPV3(mmapbatch__end, int, error, struct seg *, seg, caddr_t,
mmb->addr);
return (error);
}
/*ARGSUSED*/
static int
privcmd_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *cr, int *rval)
{
if ((mode & FMODELS) != FNATIVE)
return (EOVERFLOW);
/*
* Everything is a -native- data type.
*/
switch (cmd) {
case IOCTL_PRIVCMD_HYPERCALL:
return (do_privcmd_hypercall((void *)arg, mode, cr, rval));
case IOCTL_PRIVCMD_MMAP:
if (DOMAIN_IS_PRIVILEGED(xen_info))
return (do_privcmd_mmap((void *)arg, mode, cr));
break;
case IOCTL_PRIVCMD_MMAPBATCH:
if (DOMAIN_IS_PRIVILEGED(xen_info))
return (do_privcmd_mmapbatch((void *)arg, mode, cr));
break;
default:
break;
}
return (EINVAL);
}
/*
* The real magic happens in the segmf segment driver.
*/
/*ARGSUSED8*/
static int
privcmd_segmap(dev_t dev, off_t off, struct as *as, caddr_t *addrp,
off_t len, uint_t prot, uint_t maxprot, uint_t flags, cred_t *cr)
{
struct segmf_crargs a;
int error;
as_rangelock(as);
if ((flags & MAP_FIXED) == 0) {
map_addr(addrp, len, (offset_t)off, 0, flags);
if (*addrp == NULL) {
error = ENOMEM;
goto rangeunlock;
}
} else {
/*
* User specified address
*/
(void) as_unmap(as, *addrp, len);
}
/*
* The mapping *must* be MAP_SHARED at offset 0.
*
* (Foreign pages are treated like device memory; the
* ioctl interface allows the backing objects to be
* arbitrarily redefined to point at any machine frame.)
*/
if ((flags & MAP_TYPE) != MAP_SHARED || off != 0) {
error = EINVAL;
goto rangeunlock;
}
a.dev = dev;
a.prot = (uchar_t)prot;
a.maxprot = (uchar_t)maxprot;
error = as_map(as, *addrp, len, segmf_create, &a);
rangeunlock:
as_rangeunlock(as);
return (error);
}
static struct cb_ops privcmd_cb_ops = {
privcmd_open,
nulldev, /* close */
nodev, /* strategy */
nodev, /* print */
nodev, /* dump */
nodev, /* read */
nodev, /* write */
privcmd_ioctl,
nodev, /* devmap */
nodev, /* mmap */
privcmd_segmap,
nochpoll, /* poll */
ddi_prop_op,
NULL,
D_64BIT | D_NEW | D_MP
};
static struct dev_ops privcmd_dv_ops = {
DEVO_REV,
0,
privcmd_getinfo,
nulldev, /* identify */
nulldev, /* probe */
privcmd_attach,
privcmd_detach,
nodev, /* reset */
&privcmd_cb_ops,
0 /* struct bus_ops */
};
static struct modldrv modldrv = {
&mod_driverops,
"privcmd driver %I%",
&privcmd_dv_ops
};
static struct modlinkage modl = {
MODREV_1,
&modldrv
};
int
_init(void)
{
return (mod_install(&modl));
}
int
_fini(void)
{
return (mod_remove(&modl));
}
int
_info(struct modinfo *modinfo)
{
return (mod_info(&modl, modinfo));
}