Re: [PATCH v5 RESEND 12/17] xtensa: mm: Convert to GENERIC_IOREMAP

Mike Rapoport
2023-05-16T06:52:29Z

On Mon, May 15, 2023 at 05:08:43PM +0800, Baoquan He wrote:
> By taking GENERIC_IOREMAP method, the generic generic_ioremap_prot(),
> generic_iounmap(), and their generic wrapper ioremap_prot(), ioremap()
> and iounmap() are all visible and available to arch. Arch needs to
> provide wrapper functions to override the generic versions if there's
> arch specific handling in its ioremap_prot(), ioremap() or iounmap().
> This change will simplify implementation by removing duplicated codes
> with generic_ioremap_prot() and generic_iounmap(), and has the equivalent
> functioality as before.
>
> Here, add wrapper functions ioremap_prot(), ioremap() and iounmap() for
> xtensa's special operation when ioremap() and iounmap().
>
> Signed-off-by: Baoquan He <bhe@redhat.com>
> Cc: Chris Zankel <chris@zankel.net>
> Cc: Max Filippov <jcmvbkbc@gmail.com>

Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>

> ---
> arch/xtensa/Kconfig | 1 +
> arch/xtensa/include/asm/io.h | 32 ++++++++------------
> arch/xtensa/mm/ioremap.c | 58 +++++++++---------------------------
> 3 files changed, 27 insertions(+), 64 deletions(-)
>
> diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
> index 3c6e5471f025..474cbbff3e6c 100644
> --- a/arch/xtensa/Kconfig
> +++ b/arch/xtensa/Kconfig
> @@ -29,6 +29,7 @@ config XTENSA
> select GENERIC_LIB_UCMPDI2
> select GENERIC_PCI_IOMAP
> select GENERIC_SCHED_CLOCK
> + select GENERIC_IOREMAP if MMU
> select HAVE_ARCH_AUDITSYSCALL
> select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
> select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
> diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h
> index a5b707e1c0f4..934e58399c8c 100644
> --- a/arch/xtensa/include/asm/io.h
> +++ b/arch/xtensa/include/asm/io.h
> @@ -16,6 +16,7 @@
> #include <asm/vectors.h>
> #include <linux/bug.h>
> #include <linux/kernel.h>
> +#include <linux/pgtable.h>
>
> #include <linux/types.h>
>
> @@ -24,22 +25,24 @@
> #define PCI_IOBASE ((void __iomem *)XCHAL_KIO_BYPASS_VADDR)
>
> #ifdef CONFIG_MMU
> -
> -void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size);
> -void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size);
> -void xtensa_iounmap(volatile void __iomem *addr);
> -
> /*
> - * Return the virtual address for the specified bus memory.
> + * I/O memory mapping functions.
> */
> +void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
> + unsigned long prot);
> +#define ioremap_prot ioremap_prot
> +#define iounmap iounmap
> +
> static inline void __iomem *ioremap(unsigned long offset, unsigned long size)
> {
> if (offset >= XCHAL_KIO_PADDR
> && offset - XCHAL_KIO_PADDR < XCHAL_KIO_SIZE)
> return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_BYPASS_VADDR);
> else
> - return xtensa_ioremap_nocache(offset, size);
> + return ioremap_prot(offset, size,
> + pgprot_val(pgprot_noncached(PAGE_KERNEL)));
> }
> +#define ioremap ioremap
>
> static inline void __iomem *ioremap_cache(unsigned long offset,
> unsigned long size)
> @@ -48,21 +51,10 @@ static inline void __iomem *ioremap_cache(unsigned long offset,
> && offset - XCHAL_KIO_PADDR < XCHAL_KIO_SIZE)
> return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_CACHED_VADDR);
> else
> - return xtensa_ioremap_cache(offset, size);
> -}
> -#define ioremap_cache ioremap_cache
> + return ioremap_prot(offset, size, pgprot_val(PAGE_KERNEL));
>
> -static inline void iounmap(volatile void __iomem *addr)
> -{
> - unsigned long va = (unsigned long) addr;
> -
> - if (!(va >= XCHAL_KIO_CACHED_VADDR &&
> - va - XCHAL_KIO_CACHED_VADDR < XCHAL_KIO_SIZE) &&
> - !(va >= XCHAL_KIO_BYPASS_VADDR &&
> - va - XCHAL_KIO_BYPASS_VADDR < XCHAL_KIO_SIZE))
> - xtensa_iounmap(addr);
> }
> -
> +#define ioremap_cache ioremap_cache
> #endif /* CONFIG_MMU */
>
> #include <asm-generic/io.h>
> diff --git a/arch/xtensa/mm/ioremap.c b/arch/xtensa/mm/ioremap.c
> index a400188c16b9..8ca660b7ab49 100644
> --- a/arch/xtensa/mm/ioremap.c
> +++ b/arch/xtensa/mm/ioremap.c
> @@ -6,60 +6,30 @@
> */
>
> #include <linux/io.h>
> -#include <linux/vmalloc.h>
> #include <linux/pgtable.h>
> #include <asm/cacheflush.h>
> #include <asm/io.h>
>
> -static void __iomem *xtensa_ioremap(unsigned long paddr, unsigned long size,
> - pgprot_t prot)
> +void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
> + unsigned long prot)
> {
> - unsigned long offset = paddr & ~PAGE_MASK;
> - unsigned long pfn = __phys_to_pfn(paddr);
> - struct vm_struct *area;
> - unsigned long vaddr;
> - int err;
> -
> - paddr &= PAGE_MASK;
> -
> + unsigned long pfn = __phys_to_pfn((phys_addr));
> WARN_ON(pfn_valid(pfn));
>
> - size = PAGE_ALIGN(offset + size);
> -
> - area = get_vm_area(size, VM_IOREMAP);
> - if (!area)
> - return NULL;
> -
> - vaddr = (unsigned long)area->addr;
> - area->phys_addr = paddr;
> -
> - err = ioremap_page_range(vaddr, vaddr + size, paddr, prot);
> -
> - if (err) {
> - vunmap((void *)vaddr);
> - return NULL;
> - }
> -
> - flush_cache_vmap(vaddr, vaddr + size);
> - return (void __iomem *)(offset + vaddr);
> -}
> -
> -void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size)
> -{
> - return xtensa_ioremap(addr, size, pgprot_noncached(PAGE_KERNEL));
> + return generic_ioremap_prot(phys_addr, size, __pgprot(prot));
> }
> -EXPORT_SYMBOL(xtensa_ioremap_nocache);
> +EXPORT_SYMBOL(ioremap_prot);
>
> -void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size)
> +void iounmap(volatile void __iomem *addr)
> {
> - return xtensa_ioremap(addr, size, PAGE_KERNEL);
> -}
> -EXPORT_SYMBOL(xtensa_ioremap_cache);
> + unsigned long va = (unsigned long) addr;
>
> -void xtensa_iounmap(volatile void __iomem *io_addr)
> -{
> - void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
> + if ((va >= XCHAL_KIO_CACHED_VADDR &&
> + va - XCHAL_KIO_CACHED_VADDR < XCHAL_KIO_SIZE) ||
> + (va >= XCHAL_KIO_BYPASS_VADDR &&
> + va - XCHAL_KIO_BYPASS_VADDR < XCHAL_KIO_SIZE))
> + return;
>
> - vunmap(addr);
> + generic_iounmap(addr);
> }
> -EXPORT_SYMBOL(xtensa_iounmap);
> +EXPORT_SYMBOL(iounmap);
> --
> 2.34.1
>
>

--
Sincerely yours,
Mike.