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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH v11 05/11] x86/mm: add HYPERVISOR_memory_op to acquire guest resources
Certain memory resources associated with a guest are not necessarily
present in the guest P2M.
This patch adds the boilerplate for new memory op to allow such a resource
to be priv-mapped directly, by either a PV or HVM tools domain.
NOTE: Whilst the new op is not intrinsicly specific to the x86 architecture,
I have no means to test it on an ARM platform and so cannot verify
that it functions correctly. Hence it is currently only implemented
for x86.
Signed-off-by: Paul Durrant <paul.durrant@xxxxxxxxxx>
---
Cc: George Dunlap <george.dunlap@xxxxxxxxxxxxx>
Cc: Jan Beulich <jbeulich@xxxxxxxx>
Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Cc: George Dunlap <George.Dunlap@xxxxxxxxxxxxx>
Cc: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Cc: Tim Deegan <tim@xxxxxxx>
Cc: Wei Liu <wei.liu2@xxxxxxxxxx>
v11:
- Addressed more comments from Jan.
v9:
- Addressed more comments from Jan.
v8:
- Move the code into common as requested by Jan.
- Make the gmfn_list handle a 64-bit type to avoid limiting the MFN
range for a 32-bit tools domain.
- Add missing pad.
- Add compat code.
- Make this patch deal with purely boilerplate.
- Drop George's A-b and Wei's R-b because the changes are non-trivial,
and update Cc list now the boilerplate is common.
v5:
- Switched __copy_to/from_guest_offset() to copy_to/from_guest_offset().
---
tools/flask/policy/modules/xen.if | 4 +-
xen/arch/x86/mm/p2m.c | 3 +-
xen/common/compat/memory.c | 145 ++++++++++++++++++++++++++++++++++--
xen/common/memory.c | 90 ++++++++++++++++++++++
xen/include/asm-x86/p2m.h | 3 +
xen/include/public/memory.h | 43 ++++++++++-
xen/include/xlat.lst | 1 +
xen/include/xsm/dummy.h | 6 ++
xen/include/xsm/xsm.h | 6 ++
xen/xsm/dummy.c | 1 +
xen/xsm/flask/hooks.c | 6 ++
xen/xsm/flask/policy/access_vectors | 2 +
12 files changed, 300 insertions(+), 10 deletions(-)
diff --git a/tools/flask/policy/modules/xen.if
b/tools/flask/policy/modules/xen.if
index 55437496f6..07cba8a15d 100644
--- a/tools/flask/policy/modules/xen.if
+++ b/tools/flask/policy/modules/xen.if
@@ -52,7 +52,8 @@ define(`create_domain_common', `
settime setdomainhandle getvcpucontext set_misc_info };
allow $1 $2:domain2 { set_cpuid settsc setscheduler setclaim
set_max_evtchn set_vnumainfo get_vnumainfo cacheflush
- psr_cmt_op psr_cat_op soft_reset set_gnttab_limits };
+ psr_cmt_op psr_cat_op soft_reset set_gnttab_limits
+ resource_map };
allow $1 $2:security check_context;
allow $1 $2:shadow enable;
allow $1 $2:mmu { map_read map_write adjust memorymap physmap pinpage
mmuext_op updatemp };
@@ -152,6 +153,7 @@ define(`device_model', `
allow $1 $2_target:domain { getdomaininfo shutdown };
allow $1 $2_target:mmu { map_read map_write adjust physmap target_hack
};
allow $1 $2_target:hvm { getparam setparam hvmctl cacheattr dm };
+ allow $1 $2_target:domain2 resource_map;
')
# make_device_model(priv, dm_dom, hvm_dom)
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index c72a3cdebb..71bb9b4f93 100644
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -1132,8 +1132,7 @@ static int set_typed_p2m_entry(struct domain *d, unsigned
long gfn_l,
}
/* Set foreign mfn in the given guest's p2m table. */
-static int set_foreign_p2m_entry(struct domain *d, unsigned long gfn,
- mfn_t mfn)
+int set_foreign_p2m_entry(struct domain *d, unsigned long gfn, mfn_t mfn)
{
return set_typed_p2m_entry(d, gfn, mfn, PAGE_ORDER_4K, p2m_map_foreign,
p2m_get_hostp2m(d)->default_access);
diff --git a/xen/common/compat/memory.c b/xen/common/compat/memory.c
index 35bb259808..031d1a48ae 100644
--- a/xen/common/compat/memory.c
+++ b/xen/common/compat/memory.c
@@ -71,6 +71,7 @@ int compat_memory_op(unsigned int cmd,
XEN_GUEST_HANDLE_PARAM(void) compat)
struct xen_remove_from_physmap *xrfp;
struct xen_vnuma_topology_info *vnuma;
struct xen_mem_access_op *mao;
+ struct xen_mem_acquire_resource *mar;
} nat;
union {
struct compat_memory_reservation rsrv;
@@ -79,6 +80,7 @@ int compat_memory_op(unsigned int cmd,
XEN_GUEST_HANDLE_PARAM(void) compat)
struct compat_add_to_physmap_batch atpb;
struct compat_vnuma_topology_info vnuma;
struct compat_mem_access_op mao;
+ struct compat_mem_acquire_resource mar;
} cmp;
set_xen_guest_handle(nat.hnd, COMPAT_ARG_XLAT_VIRT_BASE);
@@ -395,6 +397,71 @@ int compat_memory_op(unsigned int cmd,
XEN_GUEST_HANDLE_PARAM(void) compat)
}
#endif
+ case XENMEM_acquire_resource:
+ {
+ xen_ulong_t *xen_frame_list = (xen_ulong_t *)(nat.mar + 1);
+ unsigned int max_nr_frames;
+
+ if ( copy_from_guest(&cmp.mar, compat, 1) ||
+ !compat_handle_okay(cmp.mar.frame_list,
+ cmp.mar.nr_frames) )
+ return -EFAULT;
+
+ /*
+ * The number of frames handled is currently limited to a
+ * small number by the underlying implementation, so the
+ * scratch space should be sufficient for bouncing the
+ * frame addresses.
+ */
+ max_nr_frames = (COMPAT_ARG_XLAT_SIZE - sizeof(*nat.mar)) /
+ sizeof(*xen_frame_list);
+
+ /* If the number of frames does exceed the maximum that can
+ * be bounced then -E2BIG is returned, but to satisfy the
+ * semantics of the hypercall then we need to get the
+ * maximum number of frames support by the implementation.
+ * This can be done by set nr_frames to zero.
+ */
+ if ( cmp.mar.nr_frames > max_nr_frames )
+ {
+ cmp.mar.nr_frames = 0;
+
+ /*
+ * Stash the maximum number of frames that can be bounced
+ * in xen_frame_list[0]. It is needed in the return path.
+ */
+ xen_frame_list[0] = max_nr_frames;
+ }
+ else if ( cmp.mar.nr_frames == 0 )
+ {
+ /*
+ * Make sure that xen_frame_list[0] is zero in the case
+ * when the caller set nr_frames to zero, so that we
+ * can distinguish this case from the above on return.
+ */
+ xen_frame_list[0] = 0;
+ }
+
+ for ( i = 0; i < cmp.mar.nr_frames; i++ )
+ {
+ compat_ulong_t frame;
+
+ if ( __copy_from_compat_offset(&frame, cmp.mar.frame_list,
+ i, 1) )
+ return -EFAULT;
+
+ xen_frame_list[i] = frame;
+ }
+
+#define XLAT_mem_acquire_resource_HNDL_frame_list(_d_, _s_) \
+ set_xen_guest_handle((_d_)->frame_list, xen_frame_list)
+
+ XLAT_mem_acquire_resource(nat.mar, &cmp.mar);
+
+#undef XLAT_mem_acquire_resource_HNDL_frame_list
+
+ break;
+ }
default:
return compat_arch_memory_op(cmd, compat);
}
@@ -402,14 +469,56 @@ int compat_memory_op(unsigned int cmd,
XEN_GUEST_HANDLE_PARAM(void) compat)
rc = do_memory_op(cmd, nat.hnd);
if ( rc < 0 )
{
- if ( rc == -ENOBUFS && op == XENMEM_get_vnumainfo )
+ switch ( op)
{
- cmp.vnuma.nr_vnodes = nat.vnuma->nr_vnodes;
- cmp.vnuma.nr_vcpus = nat.vnuma->nr_vcpus;
- cmp.vnuma.nr_vmemranges = nat.vnuma->nr_vmemranges;
- if ( __copy_to_guest(compat, &cmp.vnuma, 1) )
- rc = -EFAULT;
+ case XENMEM_get_vnumainfo:
+ if ( rc == -ENOBUFS )
+ {
+ cmp.vnuma.nr_vnodes = nat.vnuma->nr_vnodes;
+ cmp.vnuma.nr_vcpus = nat.vnuma->nr_vcpus;
+ cmp.vnuma.nr_vmemranges = nat.vnuma->nr_vmemranges;
+ if ( __copy_to_guest(compat, &cmp.vnuma, 1) )
+ rc = -EFAULT;
+ }
+
+ break;
+
+ case XENMEM_acquire_resource:
+ {
+ xen_ulong_t *xen_frame_list = (xen_ulong_t *)(nat.mar + 1);
+
+ if ( rc == -EINVAL && xen_frame_list[0] != 0 )
+ {
+ /*
+ * The value of nr_frames passed to the implementation
+ * was not the value passed by the caller, it was
+ * overridden.
+ * The value in xen_frame_list[0] is the maximum
+ * number of frames that can be bounced so we need
+ * to set cmp.nr_frames to the minimum of this and
+ * the maximum number of frames allowed by the
+ * implementation before passing back to the caller.
+ */
+ cmp.mar.nr_frames = min_t(unsigned int,
+ xen_frame_list[0],
+ nat.mar->nr_frames);
+ rc = -E2BIG;
+ }
+
+ /* In either of these cases nr_frames is an OUT value */
+ if ( rc == -EINVAL || rc == -E2BIG )
+ {
+ if ( copy_to_guest(compat, &cmp.mar, 1) )
+ rc = -EFAULT;
+ }
+
+ break;
+ }
+ default:
+ break;
}
+
+ /* Break out of the do loop */
break;
}
@@ -535,6 +644,30 @@ int compat_memory_op(unsigned int cmd,
XEN_GUEST_HANDLE_PARAM(void) compat)
rc = -EFAULT;
break;
+ case XENMEM_acquire_resource:
+ {
+ xen_ulong_t *xen_frame_list = (xen_ulong_t *)(nat.mar + 1);
+ compat_ulong_t *compat_frame_list =
+ (compat_ulong_t *)(nat.mar + 1);
+
+ /* NOTE: the compat array overwrites the native array */
+ for ( i = 0; i < cmp.mar.nr_frames; i++ )
+ {
+ compat_ulong_t frame = xen_frame_list[i];
+
+ if ( frame != xen_frame_list[i] )
+ return -ERANGE;
+
+ compat_frame_list[i] = frame;
+ }
+
+ if ( __copy_to_compat_offset(cmp.mar.frame_list, 0,
+ compat_frame_list,
+ cmp.mar.nr_frames) )
+ return -EFAULT;
+
+ break;
+ }
default:
domain_crash(current->domain);
split = 0;
diff --git a/xen/common/memory.c b/xen/common/memory.c
index ad987e0f29..a88fc83565 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -965,6 +965,88 @@ static long xatp_permission_check(struct domain *d,
unsigned int space)
return xsm_add_to_physmap(XSM_TARGET, current->domain, d);
}
+static int acquire_resource(XEN_GUEST_HANDLE_PARAM(void) arg)
+{
+ struct domain *d, *currd = current->domain;
+ xen_mem_acquire_resource_t xmar;
+ unsigned long mfn_list[2];
+ int rc;
+
+ if ( copy_from_guest(&xmar, arg, 1) )
+ return -EFAULT;
+
+ if ( xmar.pad != 0 )
+ return -EINVAL;
+
+ if ( xmar.nr_frames == 0 ||
+ xmar.nr_frames > ARRAY_SIZE(mfn_list) )
+ {
+ rc = xmar.nr_frames == 0 ? -EINVAL : -E2BIG;
+ xmar.nr_frames = ARRAY_SIZE(mfn_list);
+
+ if ( copy_to_guest(arg, &xmar, 1) )
+ return -EFAULT;
+
+ return rc;
+ }
+
+ d = rcu_lock_domain_by_any_id(xmar.domid);
+ if ( d == NULL )
+ return -ESRCH;
+
+ rc = xsm_domain_resource_map(XSM_DM_PRIV, d);
+ if ( rc )
+ goto out;
+
+ switch ( xmar.type )
+ {
+ default:
+ rc = -EOPNOTSUPP;
+ break;
+ }
+
+ if ( rc )
+ goto out;
+
+ if ( !paging_mode_translate(currd) )
+ {
+ if ( copy_to_guest(xmar.frame_list, mfn_list, xmar.nr_frames) )
+ rc = -EFAULT;
+ }
+ else
+ {
+ xen_pfn_t gfn_list[ARRAY_SIZE(mfn_list)];
+ unsigned int i;
+
+ rc = -EFAULT;
+ if ( copy_from_guest(gfn_list, xmar.frame_list,
+ ARRAY_SIZE(gfn_list)) )
+ goto out;
+
+ for ( i = 0; i < xmar.nr_frames; i++ )
+ {
+ rc = set_foreign_p2m_entry(currd, gfn_list[i],
+ _mfn(mfn_list[i]));
+ if ( rc )
+ {
+ while ( i-- != 0 )
+ {
+ int ignore;
+
+ ignore = guest_physmap_remove_page(
+ currd, _gfn(gfn_list[i]), _mfn(mfn_list[i]), 0);
+ }
+
+ goto out;
+ }
+ }
+ }
+
+ out:
+ rcu_unlock_domain(d);
+ return rc;
+}
+
long do_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
{
struct domain *d, *curr_d = current->domain;
@@ -1406,6 +1488,14 @@ long do_memory_op(unsigned long cmd,
XEN_GUEST_HANDLE_PARAM(void) arg)
}
#endif
+ case XENMEM_acquire_resource:
+#ifdef CONFIG_X86
+ rc = acquire_resource(arg);
+#else
+ rc = -EOPNOTSUPP;
+#endif
+ break;
+
default:
rc = arch_memory_op(cmd, arg);
break;
diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h
index 17b1d0c8d3..44f7ec088c 100644
--- a/xen/include/asm-x86/p2m.h
+++ b/xen/include/asm-x86/p2m.h
@@ -620,6 +620,9 @@ void p2m_memory_type_changed(struct domain *d);
int p2m_is_logdirty_range(struct p2m_domain *, unsigned long start,
unsigned long end);
+/* Set foreign entry in the p2m table (for priv-mapping) */
+int set_foreign_p2m_entry(struct domain *d, unsigned long gfn, mfn_t mfn);
+
/* Set mmio addresses in the p2m table (for pass-through) */
int set_mmio_p2m_entry(struct domain *d, unsigned long gfn, mfn_t mfn,
unsigned int order, p2m_access_t access);
diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h
index 29386df98b..b7cf753d75 100644
--- a/xen/include/public/memory.h
+++ b/xen/include/public/memory.h
@@ -599,6 +599,47 @@ struct xen_reserved_device_memory_map {
typedef struct xen_reserved_device_memory_map xen_reserved_device_memory_map_t;
DEFINE_XEN_GUEST_HANDLE(xen_reserved_device_memory_map_t);
+/*
+ * Get the pages for a particular guest resource, so that they can be
+ * mapped directly by a tools domain.
+ */
+#define XENMEM_acquire_resource 28
+struct xen_mem_acquire_resource {
+ /* IN - the domain whose resource is to be mapped */
+ domid_t domid;
+ /* IN - the type of resource */
+ uint16_t type;
+ /*
+ * IN - a type-specific resource identifier, which must be zero
+ * unless stated otherwise.
+ */
+ uint32_t id;
+ /* IN/OUT - As an IN parameter number of (4K) frames of the resource
+ * to be mapped. However, if the specified value is 0 then
+ * -EINVAL will be returned and this field will be set to the
+ * maximum value supported by the implementation. Also,
+ * if the specified value exceeds the implementaton limit
+ * then -E2BIG will be returned and, similarly, this field
+ * will be set the maximum value supported by the
+ * implementation.
+ */
+ uint32_t nr_frames;
+ uint32_t pad;
+ /* IN - the index of the initial frame to be mapped. This parameter
+ * is optional if nr_frames is 0.
+ */
+ uint64_aligned_t frame;
+ /* IN/OUT - If the tools domain is PV then, upon return, frame_list
+ * will be populated with the MFNs of the resource.
+ * If the tools domain is HVM then it is expected that, on
+ * entry, frame_list will be populated with a list of GFNs
+ * that will be mapped to the MFNs of the resource.
+ * This parameter is optional if nr_frames is 0.
+ */
+ XEN_GUEST_HANDLE(xen_ulong_t) frame_list;
+};
+typedef struct xen_mem_acquire_resource xen_mem_acquire_resource_t;
+
#endif /* defined(__XEN__) || defined(__XEN_TOOLS__) */
/*
@@ -650,7 +691,7 @@ struct xen_vnuma_topology_info {
typedef struct xen_vnuma_topology_info xen_vnuma_topology_info_t;
DEFINE_XEN_GUEST_HANDLE(xen_vnuma_topology_info_t);
-/* Next available subop number is 28 */
+/* Next available subop number is 29 */
#endif /* __XEN_PUBLIC_MEMORY_H__ */
diff --git a/xen/include/xlat.lst b/xen/include/xlat.lst
index 0f17000ea7..5835872334 100644
--- a/xen/include/xlat.lst
+++ b/xen/include/xlat.lst
@@ -83,6 +83,7 @@
! memory_map memory.h
! memory_reservation memory.h
! mem_access_op memory.h
+! mem_acquire_resource memory.h
! pod_target memory.h
! remove_from_physmap memory.h
! reserved_device_memory_map memory.h
diff --git a/xen/include/xsm/dummy.h b/xen/include/xsm/dummy.h
index ba89ea4bc1..8f04d59a3e 100644
--- a/xen/include/xsm/dummy.h
+++ b/xen/include/xsm/dummy.h
@@ -724,3 +724,9 @@ static XSM_INLINE int xsm_xen_version (XSM_DEFAULT_ARG
uint32_t op)
return xsm_default_action(XSM_PRIV, current->domain, NULL);
}
}
+
+static XSM_INLINE int xsm_domain_resource_map(XSM_DEFAULT_ARG struct domain *d)
+{
+ XSM_ASSERT_ACTION(XSM_DM_PRIV);
+ return xsm_default_action(action, current->domain, d);
+}
diff --git a/xen/include/xsm/xsm.h b/xen/include/xsm/xsm.h
index 7f7feffc68..d0db860ae0 100644
--- a/xen/include/xsm/xsm.h
+++ b/xen/include/xsm/xsm.h
@@ -180,6 +180,7 @@ struct xsm_operations {
int (*dm_op) (struct domain *d);
#endif
int (*xen_version) (uint32_t cmd);
+ int (*domain_resource_map) (struct domain *d);
};
#ifdef CONFIG_XSM
@@ -692,6 +693,11 @@ static inline int xsm_xen_version (xsm_default_t def,
uint32_t op)
return xsm_ops->xen_version(op);
}
+static inline int xsm_domain_resource_map(xsm_default_t def, struct domain *d)
+{
+ return xsm_ops->domain_resource_map(d);
+}
+
#endif /* XSM_NO_WRAPPERS */
#ifdef CONFIG_MULTIBOOT
diff --git a/xen/xsm/dummy.c b/xen/xsm/dummy.c
index 479b103614..6e751199ee 100644
--- a/xen/xsm/dummy.c
+++ b/xen/xsm/dummy.c
@@ -157,4 +157,5 @@ void __init xsm_fixup_ops (struct xsm_operations *ops)
set_to_dummy_if_null(ops, dm_op);
#endif
set_to_dummy_if_null(ops, xen_version);
+ set_to_dummy_if_null(ops, domain_resource_map);
}
diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
index 7b005af834..7e9efcd865 100644
--- a/xen/xsm/flask/hooks.c
+++ b/xen/xsm/flask/hooks.c
@@ -1718,6 +1718,11 @@ static int flask_xen_version (uint32_t op)
}
}
+static int flask_domain_resource_map(struct domain *d)
+{
+ return current_has_perm(d, SECCLASS_DOMAIN2, DOMAIN2__RESOURCE_MAP);
+}
+
long do_flask_op(XEN_GUEST_HANDLE_PARAM(xsm_op_t) u_flask_op);
int compat_flask_op(XEN_GUEST_HANDLE_PARAM(xsm_op_t) u_flask_op);
@@ -1851,6 +1856,7 @@ static struct xsm_operations flask_ops = {
.dm_op = flask_dm_op,
#endif
.xen_version = flask_xen_version,
+ .domain_resource_map = flask_domain_resource_map,
};
void __init flask_init(const void *policy_buffer, size_t policy_size)
diff --git a/xen/xsm/flask/policy/access_vectors
b/xen/xsm/flask/policy/access_vectors
index 3a2d863b8f..341ade1f7d 100644
--- a/xen/xsm/flask/policy/access_vectors
+++ b/xen/xsm/flask/policy/access_vectors
@@ -250,6 +250,8 @@ class domain2
psr_cat_op
# XEN_DOMCTL_set_gnttab_limits
set_gnttab_limits
+# XENMEM_resource_map
+ resource_map
}
# Similar to class domain, but primarily contains domctls related to HVM
domains
--
2.11.0
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