x86/paging: move update_paging_modes() hook

The hook isn't mode dependent, hence it's misplaced in struct
paging_mode. (Or alternatively I see no reason why the alloc_page() and
free_page() hooks don't also live there.) Move it to struct
paging_domain.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>

xen/arch/x86/include/asm/domain.h

@@ -235,6 +235,8 @@ struct paging_domain {
      * (used by p2m and log-dirty code for their tries) */
     struct page_info * (*alloc_page)(struct domain *d);
     void (*free_page)(struct domain *d, struct page_info *pg);
+
+    void (*update_paging_modes)(struct vcpu *v);
 };
 
 struct paging_vcpu {

xen/arch/x86/include/asm/paging.h

@@ -139,7 +139,6 @@ struct paging_mode {
 #endif
     void          (*update_cr3            )(struct vcpu *v, int do_locking,
                                             bool noflush);
-    void          (*update_paging_modes   )(struct vcpu *v);
     bool          (*flush_tlb             )(const unsigned long *vcpu_bitmap);
 
     unsigned int guest_levels;
@@ -315,7 +314,7 @@ static inline void paging_update_cr3(struct vcpu *v, bool noflush)
  * has changed, and when bringing up a VCPU for the first time. */
 static inline void paging_update_paging_modes(struct vcpu *v)
 {
-    paging_get_hostmode(v)->update_paging_modes(v);
+    v->domain->arch.paging.update_paging_modes(v);
 }
 
 #ifdef CONFIG_PV

xen/arch/x86/mm/hap/hap.c

@@ -443,6 +443,9 @@ static void hap_destroy_monitor_table(struct vcpu* v, mfn_t mmfn)
 /************************************************/
 /*          HAP DOMAIN LEVEL FUNCTIONS          */
 /************************************************/
+
+static void cf_check hap_update_paging_modes(struct vcpu *v);
+
 void hap_domain_init(struct domain *d)
 {
     static const struct log_dirty_ops hap_ops = {
@@ -453,6 +456,8 @@ void hap_domain_init(struct domain *d)
 
     /* Use HAP logdirty mechanism. */
     paging_log_dirty_init(d, &hap_ops);
+
+    d->arch.paging.update_paging_modes = hap_update_paging_modes;
 }
 
 /* return 0 for success, -errno for failure */
@@ -842,7 +847,6 @@ static const struct paging_mode hap_paging_real_mode = {
     .gva_to_gfn             = hap_gva_to_gfn_real_mode,
     .p2m_ga_to_gfn          = hap_p2m_ga_to_gfn_real_mode,
     .update_cr3             = hap_update_cr3,
-    .update_paging_modes    = hap_update_paging_modes,
     .flush_tlb              = flush_tlb,
     .guest_levels           = 1
 };
@@ -853,7 +857,6 @@ static const struct paging_mode hap_paging_protected_mode = {
     .gva_to_gfn             = hap_gva_to_gfn_2_levels,
     .p2m_ga_to_gfn          = hap_p2m_ga_to_gfn_2_levels,
     .update_cr3             = hap_update_cr3,
-    .update_paging_modes    = hap_update_paging_modes,
     .flush_tlb              = flush_tlb,
     .guest_levels           = 2
 };
@@ -864,7 +867,6 @@ static const struct paging_mode hap_paging_pae_mode = {
     .gva_to_gfn             = hap_gva_to_gfn_3_levels,
     .p2m_ga_to_gfn          = hap_p2m_ga_to_gfn_3_levels,
     .update_cr3             = hap_update_cr3,
-    .update_paging_modes    = hap_update_paging_modes,
     .flush_tlb              = flush_tlb,
     .guest_levels           = 3
 };
@@ -875,7 +877,6 @@ static const struct paging_mode hap_paging_long_mode = {
     .gva_to_gfn             = hap_gva_to_gfn_4_levels,
     .p2m_ga_to_gfn          = hap_p2m_ga_to_gfn_4_levels,
     .update_cr3             = hap_update_cr3,
-    .update_paging_modes    = hap_update_paging_modes,
     .flush_tlb              = flush_tlb,
     .guest_levels           = 4
 };

xen/arch/x86/mm/shadow/common.c

@@ -83,6 +83,8 @@ static int cf_check sh_enable_log_dirty(struct domain *, bool log_global);
 static int cf_check sh_disable_log_dirty(struct domain *);
 static void cf_check sh_clean_dirty_bitmap(struct domain *);
 
+static void cf_check shadow_update_paging_modes(struct vcpu *);
+
 /* Set up the shadow-specific parts of a domain struct at start of day.
  * Called for every domain from arch_domain_create() */
 int shadow_domain_init(struct domain *d)
@@ -98,6 +100,8 @@ int shadow_domain_init(struct domain *d)
     /* Use shadow pagetables for log-dirty support */
     paging_log_dirty_init(d, &sh_ops);
 
+    d->arch.paging.update_paging_modes = shadow_update_paging_modes;
+
 #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC)
     d->arch.paging.shadow.oos_active = 0;
 #endif
@@ -2514,7 +2518,12 @@ static void sh_update_paging_modes(struct vcpu *v)
     v->arch.paging.mode->update_cr3(v, 0, false);
 }
 
-void cf_check shadow_update_paging_modes(struct vcpu *v)
+/*
+ * Update all the things that are derived from the guest's CR0/CR3/CR4.
+ * Called to initialize paging structures if the paging mode has changed,
+ * and when bringing up a VCPU for the first time.
+ */
+static void cf_check shadow_update_paging_modes(struct vcpu *v)
 {
     paging_lock(v->domain);
     sh_update_paging_modes(v);

xen/arch/x86/mm/shadow/multi.c

@@ -4167,7 +4167,6 @@ const struct paging_mode sh_paging_mode = {
     .gva_to_gfn                    = sh_gva_to_gfn,
 #endif
     .update_cr3                    = sh_update_cr3,
-    .update_paging_modes           = shadow_update_paging_modes,
     .flush_tlb                     = shadow_flush_tlb,
     .guest_levels                  = GUEST_PAGING_LEVELS,
 #ifdef CONFIG_PV

xen/arch/x86/mm/shadow/none.c

@@ -18,8 +18,14 @@ static void cf_check _clean_dirty_bitmap(struct domain *d)
     ASSERT(is_pv_domain(d));
 }
 
+static void cf_check _update_paging_modes(struct vcpu *v)
+{
+    ASSERT_UNREACHABLE();
+}
+
 int shadow_domain_init(struct domain *d)
 {
+    /* For HVM set up pointers for safety, then fail. */
     static const struct log_dirty_ops sh_none_ops = {
         .enable  = _enable_log_dirty,
         .disable = _disable_log_dirty,
@@ -27,6 +33,9 @@ int shadow_domain_init(struct domain *d)
     };
 
     paging_log_dirty_init(d, &sh_none_ops);
+
+    d->arch.paging.update_paging_modes = _update_paging_modes;
+
     return is_hvm_domain(d) ? -EOPNOTSUPP : 0;
 }
 
@@ -57,11 +66,6 @@ static void cf_check _update_cr3(struct vcpu *v, int do_locking, bool noflush)
     ASSERT_UNREACHABLE();
 }
 
-static void cf_check _update_paging_modes(struct vcpu *v)
-{
-    ASSERT_UNREACHABLE();
-}
-
 static const struct paging_mode sh_paging_none = {
     .page_fault                    = _page_fault,
     .invlpg                        = _invlpg,
@@ -69,7 +73,6 @@ static const struct paging_mode sh_paging_none = {
     .gva_to_gfn                    = _gva_to_gfn,
 #endif
     .update_cr3                    = _update_cr3,
-    .update_paging_modes           = _update_paging_modes,
 };
 
 void shadow_vcpu_init(struct vcpu *v)

xen/arch/x86/mm/shadow/private.h

@@ -434,11 +434,6 @@ void cf_check sh_write_guest_entry(
 intpte_t cf_check sh_cmpxchg_guest_entry(
     struct vcpu *v, intpte_t *p, intpte_t old, intpte_t new, mfn_t gmfn);
 
-/* Update all the things that are derived from the guest's CR0/CR3/CR4.
- * Called to initialize paging structures if the paging mode
- * has changed, and when bringing up a VCPU for the first time. */
-void cf_check shadow_update_paging_modes(struct vcpu *v);
-
 /* Unhook the non-Xen mappings in this top-level shadow mfn.
  * With user_only == 1, unhooks only the user-mode mappings. */
 void shadow_unhook_mappings(struct domain *d, mfn_t smfn, int user_only);