[09/16] x86/shadow: OOS mode is HVM-only

Commit Message

Jan Beulich March 22, 2023, 9:34 a.m. UTC

XEN_DOMCTL_CDF_oos_off is forced set for PV domains, so the logic can't
ever be engaged for them. Conditionalize respective fields and remove
the respective bit from SHADOW_OPTIMIZATIONS when !HVM. As a result the
SH_type_oos_snapshot constant can disappear altogether in that case, and
a couple of #ifdef-s can also be dropped/combined.

Signed-off-by: Jan Beulich <[e-mail]>

Comments

Andrew Cooper March 23, 2023, 1:42 p.m. UTC | #1

On 22/03/2023 9:34 am, Jan Beulich wrote:
> XEN_DOMCTL_CDF_oos_off is forced set for PV domains, so the logic can't
> ever be engaged for them. Conditionalize respective fields and remove
> the respective bit from SHADOW_OPTIMIZATIONS when !HVM. As a result the
> SH_type_oos_snapshot constant can disappear altogether in that case, and
> a couple of #ifdef-s can also be dropped/combined.
>
> Signed-off-by: Jan Beulich <[e-mail]>

Acked-by: Andrew Cooper <[e-mail]>

Patch

--- a/xen/arch/x86/include/asm/domain.h
+++ b/xen/arch/x86/include/asm/domain.h
@@ -113,10 +113,10 @@  struct shadow_domain {
     /* Fast MMIO path heuristic */
     bool has_fast_mmio_entries;
 
+#ifdef CONFIG_HVM
     /* OOS */
     bool_t oos_active;
 
-#ifdef CONFIG_HVM
     /* Has this domain ever used HVMOP_pagetable_dying? */
     bool_t pagetable_dying_op;
 #endif
@@ -152,7 +152,6 @@  struct shadow_vcpu {
     unsigned long last_emulated_frame;
     /* Last MFN that we emulated a write successfully */
     unsigned long last_emulated_mfn;
-#endif
 
     /* Shadow out-of-sync: pages that this vcpu has let go out of sync */
     mfn_t oos[SHADOW_OOS_PAGES];
@@ -163,7 +162,6 @@  struct shadow_vcpu {
         unsigned long off[SHADOW_OOS_FIXUPS];
     } oos_fixup[SHADOW_OOS_PAGES];
 
-#ifdef CONFIG_HVM
     bool_t pagetable_dying;
 #endif
 #endif
--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -296,7 +296,6 @@  static int sh_remove_write_access_from_s
 
     switch ( mfn_to_page(smfn)->u.sh.type )
     {
-#ifdef CONFIG_HVM
     case SH_type_l1_32_shadow:
     case SH_type_fl1_32_shadow:
         return SHADOW_INTERNAL_NAME(sh_rm_write_access_from_sl1p, 2)
@@ -306,7 +305,6 @@  static int sh_remove_write_access_from_s
     case SH_type_fl1_pae_shadow:
         return SHADOW_INTERNAL_NAME(sh_rm_write_access_from_sl1p, 3)
             (d, gmfn, smfn, off);
-#endif
 
     case SH_type_l1_64_shadow:
     case SH_type_fl1_64_shadow:
--- a/xen/arch/x86/mm/shadow/private.h
+++ b/xen/arch/x86/mm/shadow/private.h
@@ -69,7 +69,8 @@  extern int shadow_audit_enable;
 #ifdef CONFIG_HVM
 #define SHADOW_OPTIMIZATIONS     0x1ff
 #else
-#define SHADOW_OPTIMIZATIONS     (0x1ff & ~SHOPT_FAST_EMULATION)
+#define SHADOW_OPTIMIZATIONS     (0x1ff & ~(SHOPT_OUT_OF_SYNC | \
+                                            SHOPT_FAST_EMULATION))
 #endif
 
 
@@ -205,8 +206,7 @@  extern void shadow_audit_tables(struct v
 #define SH_type_max_shadow     6U
 #define SH_type_p2m_table      7U /* in use as the p2m table */
 #define SH_type_monitor_table  8U /* in use as a monitor table */
-#define SH_type_oos_snapshot   9U /* in use as OOS snapshot */
-#define SH_type_unused        10U
+#define SH_type_unused         9U
 #endif
 
 #ifndef CONFIG_PV32 /* Unused (but uglier to #ifdef above): */
@@ -323,8 +323,6 @@  static inline void sh_terminate_list(str
 #define SHF_out_of_sync (1u << (SH_type_max_shadow + 1))
 #define SHF_oos_may_write (1u << (SH_type_max_shadow + 2))
 
-#endif /* (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) */
-
 static inline int sh_page_has_multiple_shadows(struct page_info *pg)
 {
     u32 shadows;
@@ -335,7 +333,6 @@  static inline int sh_page_has_multiple_s
     return shadows && (shadows & (shadows - 1));
 }
 
-#if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC)
 /* The caller must verify this is reasonable to call; i.e., valid mfn,
  * domain is translated, &c */
 static inline int page_is_out_of_sync(struct page_info *p)