On 2/6/23 11:59 PM, Juergen Gross wrote:
> 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.
>
> Signed-off-by: Juergen Gross
> Reviewed-by: Boris Ostrovsky
Reviewed-by: Srivatsa S. Bhat (VMware)
Regards,
Srivatsa
VMware Photon OS
> ---
> V2:
> - expand commit message (Srivatsa S. Bhat)
> ---
> arch/x86/include/asm/mmu_context.h| 4 ++--
> arch/x86/include/asm/paravirt.h | 14 +++---
> arch/x86/include/asm/paravirt_types.h | 7 ++-
> arch/x86/kernel/paravirt.c| 3 +--
> arch/x86/mm/init.c| 2 +-
> arch/x86/xen/mmu_pv.c | 12 ++--
> 6 files changed, 11 insertions(+), 31 deletions(-)
>
> diff --git a/arch/x86/include/asm/mmu_context.h
> b/arch/x86/include/asm/mmu_context.h
> index b8d40ddeab00..6a14b6c2165c 100644
> --- a/arch/x86/include/asm/mmu_context.h
> +++ b/arch/x86/include/asm/mmu_context.h
> @@ -134,7 +134,7 @@ 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);
>
> @@ -167,7 +167,7 @@ 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);
> }
>
> diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
> index 73e9522db7c1..07bbdceaf35a 100644
> --- a/arch/x86/include/asm/paravirt.h
> +++ b/arch/x86/include/asm/paravirt.h
> @@ -332,16 +332,9 @@ 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)
> @@ -787,8 +780,7 @@ 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
> diff --git a/arch/x86/include/asm/paravirt_types.h
> b/arch/x86/include/asm/paravirt_types.h
> index 8c1da419260f..71bf64b963df 100644
> --- a/arch/x86/include/asm/paravirt_types.h
> +++ b/arch/x86/include/asm/paravirt_types.h
> @@ -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);
> diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
> index 327757afb027..ff1109b9c6cd 100644
> --- a/arch/x86/kernel/paravirt.c
> +++ b/arch/x86/kernel/paravirt.c
> @@ -352,8 +352,7 @@ 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,
> diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
> index cb258f58fdc8..cbc53da4c1b4 100644
> --- a/arch/x86/mm/init.c
> +++ b/arch/x86/mm/init.c
> @@ -806,7 +806,7 @@ void __init
