Re: [PATCH v2] fs: ntfs: Disable NTFS_RW for PPC

[Guenter Roeck <linux@roeck-us.net>]

On Tue, Nov 23, 2021 at 10:43:48PM +1100, Michael Ellerman wrote:
[ ... ]
> >
> > So we are looking for something like
> >
> > config DISABLE_NTFS_RW
> > 	bool
> > 	default y if PAGE_SIZE_256KB || PPC_256K_PAGES || \
> > 		PAGE_SIZE_64KB || ARM64_64K_PAGES || IA64_PAGE_SIZE_64KB || \
> > 		PARISC_PAGE_SIZE_64KB || PPC_64K_PAGES
> >
> > Anything else ?
> 
> Can we do something like this instead?
> 
> I'm pretty sure it does what we want for NTFS, and also for VMXNET3.
> 
> It is not pretty, but at least keeps the arch specifics out of driver
> Kconfigs.
> 
> cheers
> 
> 
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 26b8ed11639d..d3c4ab249e9c 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -991,6 +991,16 @@ config HAVE_ARCH_COMPAT_MMAP_BASES
>  	  and vice-versa 32-bit applications to call 64-bit mmap().
>  	  Required for applications doing different bitness syscalls.
>  
> +config PAGE_SIZE_LESS_THAN_64KB
> +	def_bool y
> +	depends on !ARM64_64K_PAGES
> +	depends on !IA64_PAGE_SIZE_64KB
> +	depends on !PAGE_SIZE_64KB
> +	depends on !PARISC_PAGE_SIZE_64KB
> +	depends on !PPC_64K_PAGES
> +	depends on !PPC_256K_PAGES
> +	depends on !PAGE_SIZE_256KB
> +

Sure, works for me. I'll wait another day or two for additional feedback
before sending out v3.

Guenter

>  # This allows to use a set of generic functions to determine mmap base
>  # address by giving priority to top-down scheme only if the process
>  # is not in legacy mode (compat task, unlimited stack size or
> diff --git a/fs/ntfs/Kconfig b/fs/ntfs/Kconfig
> index 1667a7e590d8..f93e69a61283 100644
> --- a/fs/ntfs/Kconfig
> +++ b/fs/ntfs/Kconfig
> @@ -52,6 +52,7 @@ config NTFS_DEBUG
>  config NTFS_RW
>  	bool "NTFS write support"
>  	depends on NTFS_FS
> +	depends on PAGE_SIZE_LESS_THAN_64KB
>  	help
>  	  This enables the partial, but safe, write support in the NTFS driver.
>