[PATCH v3 07/18] powerpc: Remove direct call to mmap2 syscall handlers

[Christophe Leroy]

Le 19/08/2022 à 05:37, Rohan McLure a écrit :
> Syscall handlers should not be invoked internally by their symbol names,
> as these symbols defined by the architecture-defined SYSCALL_DEFINE
> macro. Move the compatibility syscall definition for mmap2 to
> syscalls.c, so that all mmap implementations can share an inline helper
> function, as is done with the personality handlers.

Shouldn't this be done prior to patch 5 ?

> 
> Signed-off-by: Rohan McLure <rmclure at linux.ibm.com>
> ---
> V1 -> V2: Move mmap2 compat implementation to asm/kernel/syscalls.c.
> ---
>   arch/powerpc/kernel/sys_ppc32.c | 10 ----------
>   arch/powerpc/kernel/syscalls.c  | 11 +++++++++++
>   2 files changed, 11 insertions(+), 10 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/sys_ppc32.c b/arch/powerpc/kernel/sys_ppc32.c
> index 60cb5b4413b0..dd9039671227 100644
> --- a/arch/powerpc/kernel/sys_ppc32.c
> +++ b/arch/powerpc/kernel/sys_ppc32.c
> @@ -25,7 +25,6 @@
>   #include <linux/poll.h>
>   #include <linux/personality.h>
>   #include <linux/stat.h>
> -#include <linux/mman.h>
>   #include <linux/in.h>
>   #include <linux/syscalls.h>
>   #include <linux/unistd.h>
> @@ -48,15 +47,6 @@
>   #include <asm/syscalls.h>
>   #include <asm/switch_to.h>
>   
> -COMPAT_SYSCALL_DEFINE6(mmap2,
> -		       unsigned long, addr, size_t, len,
> -		       unsigned long, prot, unsigned long, flags,
> -		       unsigned long, fd, unsigned long, pgoff)
> -{
> -	/* This should remain 12 even if PAGE_SIZE changes */
> -	return sys_mmap(addr, len, prot, flags, fd, pgoff << 12);
> -}
> -
>   /*
>    * long long munging:
>    * The 32 bit ABI passes long longs in an odd even register pair.
> diff --git a/arch/powerpc/kernel/syscalls.c b/arch/powerpc/kernel/syscalls.c
> index e083935c5bf2..0afbcbd50433 100644
> --- a/arch/powerpc/kernel/syscalls.c
> +++ b/arch/powerpc/kernel/syscalls.c
> @@ -56,6 +56,17 @@ SYSCALL_DEFINE6(mmap2, unsigned long, addr, size_t, len,
>   	return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
>   }
>   
> +#ifdef CONFIG_COMPAT
> +COMPAT_SYSCALL_DEFINE6(mmap2,
> +		       unsigned long, addr, size_t, len,
> +		       unsigned long, prot, unsigned long, flags,
> +		       unsigned long, fd, unsigned long, pgoff)
> +{
> +	/* This should remain 12 even if PAGE_SIZE changes */
> +	return do_mmap2(addr, len, prot, flags, fd, pgoff << 12, PAGE_SHIFT-12);
> +}
> +#endif
> +
>   SYSCALL_DEFINE6(mmap, unsigned long, addr, size_t, len,
>   		unsigned long, prot, unsigned long, flags,
>   		unsigned long, fd, off_t, offset)