On March 6, 2017 5:33:28 AM PST, Borislav Petkov <b...@suse.de> wrote:
>On Mon, Mar 06, 2017 at 12:01:10AM -0700, Logan Gunthorpe wrote:
>> Well honestly my issue was solved by fixing my kernel config. I have
>no
>> idea why I had optimize for size in there in the first place.
>
>I still think that we should address the iomem memcpy Linus mentioned.
>So how about this partial revert. I've made 32-bit use the same special
>__memcpy() version.
>
>Hmmm?
>
>---
>diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
>index 7afb0e2f07f4..9e378a10796d 100644
>--- a/arch/x86/include/asm/io.h
>+++ b/arch/x86/include/asm/io.h
>@@ -201,6 +201,7 @@ extern void set_iounmap_nonlazy(void);
> #ifdef __KERNEL__
>
> #include <asm-generic/iomap.h>
>+#include <asm/string.h>
>
> /*
> * Convert a virtual cached pointer to an uncached pointer
>@@ -227,12 +228,13 @@ memset_io(volatile void __iomem *addr, unsigned
>char val, size_t count)
> * @src: The (I/O memory) source for the data
> * @count: The number of bytes to copy
> *
>- * Copy a block of data from I/O memory.
>+ * Copy a block of data from I/O memory. IO memory is different from
>+ * cached memory so we use special memcpy version.
> */
> static inline void
>memcpy_fromio(void *dst, const volatile void __iomem *src, size_t
>count)
> {
>- memcpy(dst, (const void __force *)src, count);
>+ __inline_memcpy(dst, (const void __force *)src, count);
> }
>
> /**
>@@ -241,12 +243,13 @@ memcpy_fromio(void *dst, const volatile void
>__iomem *src, size_t count)
> * @src: The (RAM) source for the data
> * @count: The number of bytes to copy
> *
>- * Copy a block of data to I/O memory.
>+ * Copy a block of data to I/O memory. IO memory is different from
>+ * cached memory so we use special memcpy version.
> */
> static inline void
> memcpy_toio(volatile void __iomem *dst, const void *src, size_t count)
> {
>- memcpy((void __force *)dst, src, count);
>+ __inline_memcpy((void __force *)dst, src, count);
> }
>
> /*
>diff --git a/arch/x86/include/asm/string_32.h
>b/arch/x86/include/asm/string_32.h
>index 3d3e8353ee5c..556fa4a975ff 100644
>--- a/arch/x86/include/asm/string_32.h
>+++ b/arch/x86/include/asm/string_32.h
>@@ -29,6 +29,7 @@ extern char *strchr(const char *s, int c);
> #define __HAVE_ARCH_STRLEN
> extern size_t strlen(const char *s);
>
>+#define __inline_memcpy __memcpy
>static __always_inline void *__memcpy(void *to, const void *from,
>size_t n)
> {
> int d0, d1, d2;
It isn't really that straightforward IMO.
For UC memory transaction size really needs to be specified explicitly at all
times and should be part of the API, rather than implicit.
For WC/WT/WB device memory, the ordinary memcpy is valid and preferred.
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
