On Tue, Jul 11, 2023 at 1:21 PM Matthew Wilcox (Oracle)
<willy@xxxxxxxxxxxxx> wrote:
>
> Provide lock_vma_under_rcu() when CONFIG_PER_VMA_LOCK is not defined
> to eliminate ifdefs in the users.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Very nice. Thanks!
Reviewed-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> ---
> arch/arm64/mm/fault.c | 2 --
> arch/powerpc/mm/fault.c | 4 ----
> arch/riscv/mm/fault.c | 4 ----
> arch/s390/mm/fault.c | 2 --
> arch/x86/mm/fault.c | 4 ----
> include/linux/mm.h | 6 ++++++
> 6 files changed, 6 insertions(+), 16 deletions(-)
>
> diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
> index b8c80f7b8a5f..2e5d1e238af9 100644
> --- a/arch/arm64/mm/fault.c
> +++ b/arch/arm64/mm/fault.c
> @@ -587,7 +587,6 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
>
> perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
>
> -#ifdef CONFIG_PER_VMA_LOCK
> if (!(mm_flags & FAULT_FLAG_USER))
> goto lock_mmap;
>
> @@ -616,7 +615,6 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
> return 0;
> }
> lock_mmap:
> -#endif /* CONFIG_PER_VMA_LOCK */
>
> retry:
> vma = lock_mm_and_find_vma(mm, addr, regs);
> diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
> index 82954d0e6906..b1723094d464 100644
> --- a/arch/powerpc/mm/fault.c
> +++ b/arch/powerpc/mm/fault.c
> @@ -469,7 +469,6 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address,
> if (is_exec)
> flags |= FAULT_FLAG_INSTRUCTION;
>
> -#ifdef CONFIG_PER_VMA_LOCK
> if (!(flags & FAULT_FLAG_USER))
> goto lock_mmap;
>
> @@ -502,7 +501,6 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address,
> return user_mode(regs) ? 0 : SIGBUS;
>
> lock_mmap:
> -#endif /* CONFIG_PER_VMA_LOCK */
>
> /* When running in the kernel we expect faults to occur only to
> * addresses in user space. All other faults represent errors in the
> @@ -552,9 +550,7 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address,
>
> mmap_read_unlock(current->mm);
>
> -#ifdef CONFIG_PER_VMA_LOCK
> done:
> -#endif
> if (unlikely(fault & VM_FAULT_ERROR))
> return mm_fault_error(regs, address, fault);
>
> diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
> index 6ea2cce4cc17..046732fcb48c 100644
> --- a/arch/riscv/mm/fault.c
> +++ b/arch/riscv/mm/fault.c
> @@ -283,7 +283,6 @@ void handle_page_fault(struct pt_regs *regs)
> flags |= FAULT_FLAG_WRITE;
> else if (cause == EXC_INST_PAGE_FAULT)
> flags |= FAULT_FLAG_INSTRUCTION;
> -#ifdef CONFIG_PER_VMA_LOCK
> if (!(flags & FAULT_FLAG_USER))
> goto lock_mmap;
>
> @@ -311,7 +310,6 @@ void handle_page_fault(struct pt_regs *regs)
> return;
> }
> lock_mmap:
> -#endif /* CONFIG_PER_VMA_LOCK */
>
> retry:
> vma = lock_mm_and_find_vma(mm, addr, regs);
> @@ -368,9 +366,7 @@ void handle_page_fault(struct pt_regs *regs)
>
> mmap_read_unlock(mm);
>
> -#ifdef CONFIG_PER_VMA_LOCK
> done:
> -#endif
> if (unlikely(fault & VM_FAULT_ERROR)) {
> tsk->thread.bad_cause = cause;
> mm_fault_error(regs, addr, fault);
> diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
> index 40a71063949b..ac8351f172bb 100644
> --- a/arch/s390/mm/fault.c
> +++ b/arch/s390/mm/fault.c
> @@ -407,7 +407,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access)
> access = VM_WRITE;
> if (access == VM_WRITE)
> flags |= FAULT_FLAG_WRITE;
> -#ifdef CONFIG_PER_VMA_LOCK
> if (!(flags & FAULT_FLAG_USER))
> goto lock_mmap;
> vma = lock_vma_under_rcu(mm, address);
> @@ -431,7 +430,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access)
> goto out;
> }
> lock_mmap:
> -#endif /* CONFIG_PER_VMA_LOCK */
> mmap_read_lock(mm);
>
> gmap = NULL;
> diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
> index b0f7add07aa5..ab778eac1952 100644
> --- a/arch/x86/mm/fault.c
> +++ b/arch/x86/mm/fault.c
> @@ -1350,7 +1350,6 @@ void do_user_addr_fault(struct pt_regs *regs,
> }
> #endif
>
> -#ifdef CONFIG_PER_VMA_LOCK
> if (!(flags & FAULT_FLAG_USER))
> goto lock_mmap;
>
> @@ -1381,7 +1380,6 @@ void do_user_addr_fault(struct pt_regs *regs,
> return;
> }
> lock_mmap:
> -#endif /* CONFIG_PER_VMA_LOCK */
>
> retry:
> vma = lock_mm_and_find_vma(mm, address, regs);
> @@ -1441,9 +1439,7 @@ void do_user_addr_fault(struct pt_regs *regs,
> }
>
> mmap_read_unlock(mm);
> -#ifdef CONFIG_PER_VMA_LOCK
> done:
> -#endif
> if (likely(!(fault & VM_FAULT_ERROR)))
> return;
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 46c442855df7..3c923a4bf213 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -813,6 +813,12 @@ static inline void assert_fault_locked(struct vm_fault *vmf)
> mmap_assert_locked(vmf->vma->vm_mm);
> }
>
> +static inline struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm,
> + unsigned long address)
> +{
> + return NULL;
> +}
> +
> #endif /* CONFIG_PER_VMA_LOCK */
>
> /*
> --
> 2.39.2
>
