On ti, 2015-04-07 at 17:31 +0100, Chris Wilson wrote:
> Currently, we only allocate a structure to hold metadata if we need to
> allocate an ioremap for every access, such as on x86-32. However, it
> would be useful to store basic information about the io-mapping, such as
> its page protection, on all platforms.
>
> Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
> Cc: linux-mm@xxxxxxxxx
> ---
> include/linux/io-mapping.h | 52 ++++++++++++++++++++++++++++------------------
> 1 file changed, 32 insertions(+), 20 deletions(-)
>
> diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h
> index 657fab4efab3..e053011f50bb 100644
> --- a/include/linux/io-mapping.h
> +++ b/include/linux/io-mapping.h
> @@ -31,16 +31,17 @@
> * See Documentation/io-mapping.txt
> */
>
> -#ifdef CONFIG_HAVE_ATOMIC_IOMAP
> -
> -#include <asm/iomap.h>
> -
> struct io_mapping {
> resource_size_t base;
> unsigned long size;
> pgprot_t prot;
> + void __iomem *iomem;
> };
>
> +
> +#ifdef CONFIG_HAVE_ATOMIC_IOMAP
> +
> +#include <asm/iomap.h>
> /*
> * For small address space machines, mapping large objects
> * into the kernel virtual space isn't practical. Where
> @@ -119,48 +120,59 @@ io_mapping_unmap(void __iomem *vaddr)
> #else
>
> #include <linux/uaccess.h>
> -
> -/* this struct isn't actually defined anywhere */
> -struct io_mapping;
> +#include <asm/pgtable_types.h>
>
> /* Create the io_mapping object*/
> static inline struct io_mapping *
> io_mapping_create_wc(resource_size_t base, unsigned long size)
> {
> - return (struct io_mapping __force *) ioremap_wc(base, size);
> + struct io_mapping *iomap;
> +
> + iomap = kmalloc(sizeof(*iomap), GFP_KERNEL);
> + if (!iomap)
> + return NULL;
> +
> + iomap->base = base;
> + iomap->size = size;
> + iomap->iomem = ioremap_wc(base, size);
> + iomap->prot = pgprot_writecombine(PAGE_KERNEL_IO);
> +
> + return iomap;
> }
>
> static inline void
> io_mapping_free(struct io_mapping *mapping)
> {
> - iounmap((void __force __iomem *) mapping);
> + iounmap(mapping->iomem);
> + kfree(mapping);
> }
>
> -/* Atomic map/unmap */
> +/* Non-atomic map/unmap */
> static inline void __iomem *
> -io_mapping_map_atomic_wc(struct io_mapping *mapping,
> - unsigned long offset)
> +io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
> {
> - pagefault_disable();
> - return ((char __force __iomem *) mapping) + offset;
> + return mapping->iomem + offset;
> }
>
> static inline void
> -io_mapping_unmap_atomic(void __iomem *vaddr)
> +io_mapping_unmap(void __iomem *vaddr)
> {
> - pagefault_enable();
> }
>
> -/* Non-atomic map/unmap */
> +/* Atomic map/unmap */
> static inline void __iomem *
> -io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
> +io_mapping_map_atomic_wc(struct io_mapping *mapping,
> + unsigned long offset)
> {
> - return ((char __force __iomem *) mapping) + offset;
> + pagefault_disable();
> + return io_mapping_map_wc(mapping, offset);
> }
>
> static inline void
> -io_mapping_unmap(void __iomem *vaddr)
> +io_mapping_unmap_atomic(void __iomem *vaddr)
> {
> + io_mapping_unmap(vaddr);
> + pagefault_enable();
> }
>
> #endif /* HAVE_ATOMIC_IOMAP */
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
