x86/paravirt: Merge activate_mm() and dup_mmap() callbacks

The two paravirt callbacks .mmu.activate_mm() and .mmu.dup_mmap() are
sharing the same implementations in all cases: for Xen PV guests they
are pinning the PGD of the new mm_struct, and for all other cases they
are a NOP.

In the end, both callbacks are meant to register an address space with
the underlying hypervisor, so there needs to be only a single callback
for that purpose.

So merge them to a common callback .mmu.enter_mmap() (in contrast to the
corresponding already existing .mmu.exit_mmap()).

As the first parameter of the old callbacks isn't used, drop it from the
replacement one.

  [ bp: Remove last occurrence of paravirt_activate_mm() in
    asm/mmu_context.h ]

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Link: https://lore.kernel.org/r/20230207075902.7539-1-jgross@suse.com

1 files changed, 3 insertions, 11 deletions

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index cf40e813b3d7..b49778664d2b 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -334,16 +334,9 @@ static inline void tss_update_io_bitmap(void)
 }
 #endif
 
-static inline void paravirt_activate_mm(struct mm_struct *prev,
-					struct mm_struct *next)
+static inline void paravirt_enter_mmap(struct mm_struct *next)
 {
-	PVOP_VCALL2(mmu.activate_mm, prev, next);
-}
-
-static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm,
-					  struct mm_struct *mm)
-{
-	PVOP_VCALL2(mmu.dup_mmap, oldmm, mm);
+	PVOP_VCALL1(mmu.enter_mmap, next);
 }
 
 static inline int paravirt_pgd_alloc(struct mm_struct *mm)
@@ -789,8 +782,7 @@ extern void default_banner(void);
 
 #ifndef __ASSEMBLY__
 #ifndef CONFIG_PARAVIRT_XXL
-static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm,
-					  struct mm_struct *mm)
+static inline void paravirt_enter_mmap(struct mm_struct *mm)
 {
 }
 #endif