diff mbox series

[XEN,v1,06/15] x86/p2m: guard altp2m code with CONFIG_VMX option

Message ID 20240416063121.3469245-1-Sergiy_Kibrik@epam.com (mailing list archive)
State Superseded
Headers show
Series x86: make cpu virtualization support configurable | expand

Commit Message

Sergiy Kibrik April 16, 2024, 6:31 a.m. UTC
Instead of using generic CONFIG_HVM option switch to a bit more specific
CONFIG_VMX option for altp2m support, as it depends on VMX. Also guard
altp2m routines, so that it can be disabled completely in the build.

Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com>
---
 xen/arch/x86/include/asm/altp2m.h  |  5 ++++-
 xen/arch/x86/include/asm/hvm/hvm.h |  7 +++++++
 xen/arch/x86/include/asm/p2m.h     | 18 +++++++++++++++++-
 xen/arch/x86/mm/Makefile           |  2 +-
 4 files changed, 29 insertions(+), 3 deletions(-)

Comments

Andrew Cooper April 16, 2024, 10:29 a.m. UTC | #1
On 16/04/2024 7:31 am, Sergiy Kibrik wrote:
> Instead of using generic CONFIG_HVM option switch to a bit more specific
> CONFIG_VMX option for altp2m support, as it depends on VMX. Also guard
> altp2m routines, so that it can be disabled completely in the build.
>
> Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com>

Altp2m is not VMX-specific.  It's just no-one has wired it up on AMD, or
accepted the long-outstanding ARM patchset where it was made to work.

If you want to compile it, you probably want CONFIG_ALTP2M.

However, it's not even x86 specific.  See the uses in common/monitor.c

CC Tamas.

~Andrew
Tamas K Lengyel April 16, 2024, 5:03 p.m. UTC | #2
On Tue, Apr 16, 2024 at 3:29 AM Andrew Cooper <andrew.cooper3@citrix.com> wrote:
>
> On 16/04/2024 7:31 am, Sergiy Kibrik wrote:
> > Instead of using generic CONFIG_HVM option switch to a bit more specific
> > CONFIG_VMX option for altp2m support, as it depends on VMX. Also guard
> > altp2m routines, so that it can be disabled completely in the build.
> >
> > Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com>
>
> Altp2m is not VMX-specific.  It's just no-one has wired it up on AMD, or
> accepted the long-outstanding ARM patchset where it was made to work.
>
> If you want to compile it, you probably want CONFIG_ALTP2M.
>
> However, it's not even x86 specific.  See the uses in common/monitor.c

As Andrew said, it is not VMX specific so shouldn't be tied to that.
Adding a CONFIG_ALTP2M would be OK.

Tamas
Sergiy Kibrik April 18, 2024, 10:47 a.m. UTC | #3
16.04.24 20:03, Tamas K Lengyel:
> On Tue, Apr 16, 2024 at 3:29 AM Andrew Cooper <andrew.cooper3@citrix.com> wrote:
>>
>> On 16/04/2024 7:31 am, Sergiy Kibrik wrote:
>>> Instead of using generic CONFIG_HVM option switch to a bit more specific
>>> CONFIG_VMX option for altp2m support, as it depends on VMX. Also guard
>>> altp2m routines, so that it can be disabled completely in the build.
>>>
>>> Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com>
>>
>> Altp2m is not VMX-specific.  It's just no-one has wired it up on AMD, or
>> accepted the long-outstanding ARM patchset where it was made to work.
>>
>> If you want to compile it, you probably want CONFIG_ALTP2M.
>>
>> However, it's not even x86 specific.  See the uses in common/monitor.c
> 
> As Andrew said, it is not VMX specific so shouldn't be tied to that.
> Adding a CONFIG_ALTP2M would be OK.
> 
understood. I shall go with CONFIG_ALTP2M option then. Thanks for 
clarification!

   -Sergiy
diff mbox series

Patch

diff --git a/xen/arch/x86/include/asm/altp2m.h b/xen/arch/x86/include/asm/altp2m.h
index e5e59cbd68..03613dc246 100644
--- a/xen/arch/x86/include/asm/altp2m.h
+++ b/xen/arch/x86/include/asm/altp2m.h
@@ -7,7 +7,7 @@ 
 #ifndef __ASM_X86_ALTP2M_H
 #define __ASM_X86_ALTP2M_H
 
-#ifdef CONFIG_HVM
+#ifdef CONFIG_VMX
 
 #include <xen/types.h>
 #include <xen/sched.h>         /* for struct vcpu, struct domain */
@@ -38,7 +38,10 @@  static inline bool altp2m_active(const struct domain *d)
 }
 
 /* Only declaration is needed. DCE will optimise it out when linking. */
+void altp2m_vcpu_initialise(struct vcpu *v);
+void altp2m_vcpu_destroy(struct vcpu *v);
 uint16_t altp2m_vcpu_idx(const struct vcpu *v);
+int altp2m_vcpu_enable_ve(struct vcpu *v, gfn_t gfn);
 void altp2m_vcpu_disable_ve(struct vcpu *v);
 
 #endif
diff --git a/xen/arch/x86/include/asm/hvm/hvm.h b/xen/arch/x86/include/asm/hvm/hvm.h
index 87a6935d97..870ebf3d3a 100644
--- a/xen/arch/x86/include/asm/hvm/hvm.h
+++ b/xen/arch/x86/include/asm/hvm/hvm.h
@@ -648,11 +648,18 @@  static inline bool hvm_hap_supported(void)
     return hvm_funcs.caps.hap;
 }
 
+#ifdef CONFIX_VMX
 /* returns true if hardware supports alternate p2m's */
 static inline bool hvm_altp2m_supported(void)
 {
     return hvm_funcs.caps.altp2m;
 }
+#else
+static inline bool hvm_altp2m_supported(void)
+{
+    return false;
+}
+#endif
 
 /* updates the current hardware p2m */
 static inline void altp2m_vcpu_update_p2m(struct vcpu *v)
diff --git a/xen/arch/x86/include/asm/p2m.h b/xen/arch/x86/include/asm/p2m.h
index 111badf89a..0b2da1fd05 100644
--- a/xen/arch/x86/include/asm/p2m.h
+++ b/xen/arch/x86/include/asm/p2m.h
@@ -581,9 +581,9 @@  static inline gfn_t mfn_to_gfn(const struct domain *d, mfn_t mfn)
         return _gfn(mfn_x(mfn));
 }
 
-#ifdef CONFIG_HVM
 #define AP2MGET_prepopulate true
 #define AP2MGET_query false
+#ifdef CONFIG_VMX
 
 /*
  * Looks up altp2m entry. If the entry is not found it looks up the entry in
@@ -593,6 +593,15 @@  static inline gfn_t mfn_to_gfn(const struct domain *d, mfn_t mfn)
 int altp2m_get_effective_entry(struct p2m_domain *ap2m, gfn_t gfn, mfn_t *mfn,
                                p2m_type_t *t, p2m_access_t *a,
                                bool prepopulate);
+#else
+static inline int altp2m_get_effective_entry(struct p2m_domain *ap2m,
+                                             gfn_t gfn, mfn_t *mfn,
+                                             p2m_type_t *t, p2m_access_t *a,
+                                             bool prepopulate)
+{
+    ASSERT_UNREACHABLE();
+    return -EOPNOTSUPP;
+}
 #endif
 
 /* Init the datastructures for later use by the p2m code */
@@ -909,8 +918,15 @@  static inline bool p2m_set_altp2m(struct vcpu *v, unsigned int idx)
 /* Switch alternate p2m for a single vcpu */
 bool p2m_switch_vcpu_altp2m_by_id(struct vcpu *v, unsigned int idx);
 
+#ifdef CONFIG_VMX
 /* Check to see if vcpu should be switched to a different p2m. */
 void p2m_altp2m_check(struct vcpu *v, uint16_t idx);
+#else
+static inline void p2m_altp2m_check(struct vcpu *v, uint16_t idx)
+{
+    /* Not supported w/o VMX */
+}
+#endif
 
 /* Flush all the alternate p2m's for a domain */
 void p2m_flush_altp2m(struct domain *d);
diff --git a/xen/arch/x86/mm/Makefile b/xen/arch/x86/mm/Makefile
index 92168290a8..3af992a6e9 100644
--- a/xen/arch/x86/mm/Makefile
+++ b/xen/arch/x86/mm/Makefile
@@ -1,7 +1,7 @@ 
 obj-y += shadow/
 obj-$(CONFIG_HVM) += hap/
 
-obj-$(CONFIG_HVM) += altp2m.o
+obj-$(CONFIG_VMX) += altp2m.o
 obj-$(CONFIG_HVM) += guest_walk_2.o guest_walk_3.o guest_walk_4.o
 obj-$(CONFIG_SHADOW_PAGING) += guest_walk_4.o
 obj-$(CONFIG_MEM_ACCESS) += mem_access.o