Commit c9ae1b10 authored by Juergen Gross's avatar Juergen Gross Committed by Borislav Petkov (AMD)
Browse files

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: default avatarJuergen Gross <jgross@suse.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: default avatarSrivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Link: https://lore.kernel.org/r/20230207075902.7539-1-jgross@suse.com
parent fe15c26e

arch/x86/include/asm/mmu_context.h

+2 −9
Original line number Diff line number Diff line
@@ -16,13 +16,6 @@ 


extern atomic64_t last_mm_ctx_id;



#ifndef CONFIG_PARAVIRT_XXL

static inline void paravirt_activate_mm(struct mm_struct *prev,

					struct mm_struct *next)

{

}

#endif	/* !CONFIG_PARAVIRT_XXL */



#ifdef CONFIG_PERF_EVENTS

DECLARE_STATIC_KEY_FALSE(rdpmc_never_available_key);

DECLARE_STATIC_KEY_FALSE(rdpmc_always_available_key);
@@ -135,7 +128,7 @@ extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, 


#define activate_mm(prev, next)			\

do {						\

	paravirt_activate_mm((prev), (next));	\

	paravirt_enter_mmap(next);		\

	switch_mm((prev), (next), NULL);	\

} while (0);
@@ -168,7 +161,7 @@ static inline void arch_dup_pkeys(struct mm_struct *oldmm, 
static inline int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)

{

	arch_dup_pkeys(oldmm, mm);

	paravirt_arch_dup_mmap(oldmm, mm);

	paravirt_enter_mmap(mm);

	return ldt_dup_context(oldmm, mm);

}

arch/x86/include/asm/paravirt.h

+3 −11
Original line number Diff line number Diff line
@@ -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

arch/x86/include/asm/paravirt_types.h

+2 −5
Original line number Diff line number Diff line
@@ -164,11 +164,8 @@ struct pv_mmu_ops { 
	unsigned long (*read_cr3)(void);

	void (*write_cr3)(unsigned long);



	/* Hooks for intercepting the creation/use of an mm_struct. */

	void (*activate_mm)(struct mm_struct *prev,

			    struct mm_struct *next);

	void (*dup_mmap)(struct mm_struct *oldmm,

			 struct mm_struct *mm);

	/* Hook for intercepting the creation/use of an mm_struct. */

	void (*enter_mmap)(struct mm_struct *mm);



	/* Hooks for allocating and freeing a pagetable top-level */

	int  (*pgd_alloc)(struct mm_struct *mm);

arch/x86/kernel/paravirt.c

+1 −2
Original line number Diff line number Diff line
@@ -363,8 +363,7 @@ struct paravirt_patch_template pv_ops = { 
	.mmu.make_pte		= PTE_IDENT,

	.mmu.make_pgd		= PTE_IDENT,



	.mmu.dup_mmap		= paravirt_nop,

	.mmu.activate_mm	= paravirt_nop,

	.mmu.enter_mmap		= paravirt_nop,



	.mmu.lazy_mode = {

		.enter		= paravirt_nop,

arch/x86/mm/init.c

+1 −1
Original line number Diff line number Diff line
@@ -806,7 +806,7 @@ void __init poking_init(void) 
	BUG_ON(!poking_mm);



	/* Xen PV guests need the PGD to be pinned. */

	paravirt_arch_dup_mmap(NULL, poking_mm);

	paravirt_enter_mmap(poking_mm);



	/*

	 * Randomize the poking address, but make sure that the following page