[PATCH v15 1/9] uaccess: add generic fallback version of copy_mc_to_user()
From: Ruidong Tian <hidden>
Date: 2026-06-18 09:21:51
Also in:
linux-arm-kernel, linux-mm, lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Madhavan Srinivasan, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Tong Tiangen <redacted> x86/powerpc has it's implementation of copy_mc_to_user(), we add generic fallback in include/linux/uaccess.h prepare for other architechures to enable CONFIG_ARCH_HAS_COPY_MC. Signed-off-by: Tong Tiangen <redacted> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Reviewed-by: Jonathan Cameron <redacted> Reviewed-by: Shuai Xue <xueshuai@linux.alibaba.com> --- arch/powerpc/include/asm/uaccess.h | 1 + arch/x86/include/asm/uaccess.h | 1 + include/linux/uaccess.h | 8 ++++++++ 3 files changed, 10 insertions(+)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index e98c628e3899..073de098d45a 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h@@ -432,6 +432,7 @@ copy_mc_to_user(void __user *to, const void *from, unsigned long n) return n; } +#define copy_mc_to_user copy_mc_to_user #endif extern size_t copy_from_user_flushcache(void *dst, const void __user *src, size_t size);
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 3a0dd3c2b233..308b0854d1d5 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h@@ -496,6 +496,7 @@ copy_mc_to_kernel(void *to, const void *from, unsigned len); unsigned long __must_check copy_mc_to_user(void __user *to, const void *from, unsigned len); +#define copy_mc_to_user copy_mc_to_user #endif /*
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 56328601218c..13b4a3a15437 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h@@ -250,6 +250,14 @@ copy_mc_to_kernel(void *dst, const void *src, size_t cnt) } #endif +#ifndef copy_mc_to_user +static inline unsigned long __must_check +copy_mc_to_user(void __user *dst, const void *src, unsigned long cnt) +{ + return copy_to_user(dst, src, cnt); +} +#endif + static __always_inline void pagefault_disabled_inc(void) { current->pagefault_disabled++;
--
2.39.3