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#include <xen/config.h>
#include <xen/types.h>
#include <xen/hypercall.h>
#include <xen/guest_access.h>
#include <xen/sched.h>
#include <xen/event.h>
#include <asm/current.h>
#include <compat/memory.h>
#define xen_domid_t domid_t
#define compat_domid_t domid_compat_t
CHECK_TYPE(domid);
#undef compat_domid_t
#undef xen_domid_t
int compat_memory_op(unsigned int cmd, XEN_GUEST_HANDLE_PARAM(void) compat)
{
int split, op = cmd & MEMOP_CMD_MASK;
long rc;
unsigned int start_extent = cmd >> MEMOP_EXTENT_SHIFT;
do
{
unsigned int i, end_extent = 0;
union {
XEN_GUEST_HANDLE_PARAM(void) hnd;
struct xen_memory_reservation *rsrv;
struct xen_memory_exchange *xchg;
struct xen_remove_from_physmap *xrfp;
} nat;
union {
struct compat_memory_reservation rsrv;
struct compat_memory_exchange xchg;
} cmp;
set_xen_guest_handle(nat.hnd, COMPAT_ARG_XLAT_VIRT_BASE);
split = 0;
switch ( op )
{
xen_pfn_t *space;
case XENMEM_increase_reservation:
case XENMEM_decrease_reservation:
case XENMEM_populate_physmap:
if ( copy_from_guest(&cmp.rsrv, compat, 1) )
return start_extent;
/* Is size too large for us to encode a continuation? */
if ( cmp.rsrv.nr_extents > (UINT_MAX >> MEMOP_EXTENT_SHIFT) )
return start_extent;
if ( !compat_handle_is_null(cmp.rsrv.extent_start) &&
!compat_handle_okay(cmp.rsrv.extent_start, cmp.rsrv.nr_extents) )
return start_extent;
end_extent = start_extent + (COMPAT_ARG_XLAT_SIZE - sizeof(*nat.rsrv)) /
sizeof(*space);
if ( end_extent > cmp.rsrv.nr_extents )
end_extent = cmp.rsrv.nr_extents;
space = (xen_pfn_t *)(nat.rsrv + 1);
#define XLAT_memory_reservation_HNDL_extent_start(_d_, _s_) \
do \
{ \
if ( !compat_handle_is_null((_s_)->extent_start) ) \
{ \
set_xen_guest_handle((_d_)->extent_start, space - start_extent); \
if ( op != XENMEM_increase_reservation ) \
{ \
for ( i = start_extent; i < end_extent; ++i ) \
{ \
compat_pfn_t pfn; \
if ( __copy_from_compat_offset(&pfn, (_s_)->extent_start, i, 1) ) \
{ \
end_extent = i; \
split = -1; \
break; \
} \
*space++ = pfn; \
} \
} \
} \
else \
{ \
set_xen_guest_handle((_d_)->extent_start, NULL); \
end_extent = cmp.rsrv.nr_extents; \
} \
} while (0)
XLAT_memory_reservation(nat.rsrv, &cmp.rsrv);
#undef XLAT_memory_reservation_HNDL_extent_start
if ( end_extent < cmp.rsrv.nr_extents )
{
nat.rsrv->nr_extents = end_extent;
++split;
}
break;
case XENMEM_exchange:
{
int order_delta;
if ( copy_from_guest(&cmp.xchg, compat, 1) )
return -EFAULT;
order_delta = cmp.xchg.out.extent_order - cmp.xchg.in.extent_order;
/* Various sanity checks. */
if ( (cmp.xchg.nr_exchanged > cmp.xchg.in.nr_extents) ||
(order_delta > 0 && (cmp.xchg.nr_exchanged & ((1U << order_delta) - 1))) ||
/* Sizes of input and output lists do not overflow an int? */
((~0U >> cmp.xchg.in.extent_order) < cmp.xchg.in.nr_extents) ||
((~0U >> cmp.xchg.out.extent_order) < cmp.xchg.out.nr_extents) ||
/* Sizes of input and output lists match? */
((cmp.xchg.in.nr_extents << cmp.xchg.in.extent_order) !=
(cmp.xchg.out.nr_extents << cmp.xchg.out.extent_order)) )
return -EINVAL;
if ( !compat_handle_okay(cmp.xchg.in.extent_start,
cmp.xchg.in.nr_extents) ||
!compat_handle_okay(cmp.xchg.out.extent_start,
cmp.xchg.out.nr_extents) )
return -EFAULT;
start_extent = cmp.xchg.nr_exchanged;
end_extent = (COMPAT_ARG_XLAT_SIZE - sizeof(*nat.xchg)) /
(((1U << ABS(order_delta)) + 1) *
sizeof(*space));
if ( end_extent == 0 )
{
printk("Cannot translate compatibility mode XENMEM_exchange extents (%u,%u)\n",
cmp.xchg.in.extent_order, cmp.xchg.out.extent_order);
return -E2BIG;
}
if ( order_delta > 0 )
end_extent <<= order_delta;
end_extent += start_extent;
if ( end_extent > cmp.xchg.in.nr_extents )
end_extent = cmp.xchg.in.nr_extents;
space = (xen_pfn_t *)(nat.xchg + 1);
/* Code below depends upon .in preceding .out. */
BUILD_BUG_ON(offsetof(xen_memory_exchange_t, in) > offsetof(xen_memory_exchange_t, out));
#define XLAT_memory_reservation_HNDL_extent_start(_d_, _s_) \
do \
{ \
set_xen_guest_handle((_d_)->extent_start, space - start_extent); \
for ( i = start_extent; i < end_extent; ++i ) \
{ \
compat_pfn_t pfn; \
if ( __copy_from_compat_offset(&pfn, (_s_)->extent_start, i, 1) ) \
return -EFAULT; \
*space++ = pfn; \
} \
if ( order_delta > 0 ) \
{ \
start_extent >>= order_delta; \
end_extent >>= order_delta; \
} \
else \
{ \
start_extent <<= -order_delta; \
end_extent <<= -order_delta; \
} \
order_delta = -order_delta; \
} while (0)
XLAT_memory_exchange(nat.xchg, &cmp.xchg);
#undef XLAT_memory_reservation_HNDL_extent_start
if ( end_extent < cmp.xchg.in.nr_extents )
{
nat.xchg->in.nr_extents = end_extent;
if ( order_delta >= 0 )
nat.xchg->out.nr_extents = end_extent >> order_delta;
else
nat.xchg->out.nr_extents = end_extent << -order_delta;
++split;
}
break;
}
case XENMEM_current_reservation:
case XENMEM_maximum_reservation:
case XENMEM_maximum_gpfn:
case XENMEM_maximum_ram_page:
nat.hnd = compat;
break;
case XENMEM_remove_from_physmap:
{
struct compat_remove_from_physmap cmp;
if ( copy_from_guest(&cmp, compat, 1) )
return -EFAULT;
XLAT_remove_from_physmap(nat.xrfp, &cmp);
break;
}
default:
return compat_arch_memory_op(cmd, compat);
}
rc = do_memory_op(cmd, nat.hnd);
if ( rc < 0 )
break;
cmd = 0;
if ( hypercall_xlat_continuation(&cmd, 0x02, nat.hnd, compat) )
{
BUG_ON(rc != __HYPERVISOR_memory_op);
BUG_ON((cmd & MEMOP_CMD_MASK) != op);
split = -1;
}
switch ( op )
{
case XENMEM_increase_reservation:
case XENMEM_decrease_reservation:
case XENMEM_populate_physmap:
end_extent = split >= 0 ? rc : cmd >> MEMOP_EXTENT_SHIFT;
if ( (op != XENMEM_decrease_reservation) &&
!guest_handle_is_null(nat.rsrv->extent_start) )
{
for ( ; start_extent < end_extent; ++start_extent )
{
compat_pfn_t pfn = nat.rsrv->extent_start.p[start_extent];
BUG_ON(pfn != nat.rsrv->extent_start.p[start_extent]);
if ( __copy_to_compat_offset(cmp.rsrv.extent_start,
start_extent, &pfn, 1) )
{
if ( split >= 0 )
{
rc = start_extent;
split = 0;
}
else
/*
* Short of being able to cancel the continuation,
* force it to restart here; eventually we shall
* get out of this state.
*/
rc = (start_extent << MEMOP_EXTENT_SHIFT) | op;
break;
}
}
}
else
{
start_extent = end_extent;
}
/* Bail if there was an error. */
if ( (split >= 0) && (end_extent != nat.rsrv->nr_extents) )
split = 0;
break;
case XENMEM_exchange:
{
DEFINE_XEN_GUEST_HANDLE(compat_memory_exchange_t);
int order_delta;
BUG_ON(split >= 0 && rc);
BUG_ON(end_extent < nat.xchg->nr_exchanged);
end_extent = nat.xchg->nr_exchanged;
order_delta = cmp.xchg.out.extent_order - cmp.xchg.in.extent_order;
if ( order_delta > 0 )
{
start_extent >>= order_delta;
BUG_ON(end_extent & ((1U << order_delta) - 1));
end_extent >>= order_delta;
}
else
{
start_extent <<= -order_delta;
end_extent <<= -order_delta;
}
for ( ; start_extent < end_extent; ++start_extent )
{
compat_pfn_t pfn = nat.xchg->out.extent_start.p[start_extent];
BUG_ON(pfn != nat.xchg->out.extent_start.p[start_extent]);
if ( __copy_to_compat_offset(cmp.xchg.out.extent_start,
start_extent, &pfn, 1) )
{
rc = -EFAULT;
break;
}
}
cmp.xchg.nr_exchanged = nat.xchg->nr_exchanged;
if ( __copy_field_to_guest(guest_handle_cast(compat,
compat_memory_exchange_t),
&cmp.xchg, nr_exchanged) )
rc = -EFAULT;
if ( rc < 0 )
{
if ( split < 0 )
/* Cannot cancel the continuation... */
domain_crash(current->domain);
return rc;
}
break;
}
case XENMEM_maximum_ram_page:
case XENMEM_current_reservation:
case XENMEM_maximum_reservation:
case XENMEM_maximum_gpfn:
case XENMEM_remove_from_physmap:
break;
default:
domain_crash(current->domain);
split = 0;
break;
}
cmd = op | (start_extent << MEMOP_EXTENT_SHIFT);
if ( split > 0 && hypercall_preempt_check() )
return hypercall_create_continuation(
__HYPERVISOR_memory_op, "ih", cmd, compat);
} while ( split > 0 );
if ( unlikely(rc > INT_MAX) )
return INT_MAX;
if ( unlikely(rc < INT_MIN) )
return INT_MIN;
return rc;
}
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