From: Linus Torvalds Date: Mon, 30 Mar 2026 21:52:45 +0000 (-0700) Subject: x86-64/arm64/powerpc: clean up and rename __copy_from_user_flushcache X-Git-Tag: v6.18.24~19 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=576d365f31d9beea188a94eab72acecf0558542b;p=thirdparty%2Fkernel%2Fstable.git x86-64/arm64/powerpc: clean up and rename __copy_from_user_flushcache commit 809b997a5ce945ab470f70c187048fe4f5df20bf upstream. This finishes the work on these odd functions that were only implemented by a handful of architectures. The 'flushcache' function was only used from the iterator code, and let's make it do the same thing that the nontemporal version does: remove the two underscores and add the user address checking. Yes, yes, the user address checking is also done at iovec import time, but we have long since walked away from the old double-underscore thing where we try to avoid address checking overhead at access time, and these functions shouldn't be so special and old-fashioned. The arm64 version already did the address check, in fact, so there it's just a matter of renaming it. For powerpc and x86-64 we now do the proper user access boilerplate. Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 1aa4ecb73429f..93d184b4da2fe 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -480,7 +480,7 @@ extern __must_check long strnlen_user(const char __user *str, long n); #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE extern unsigned long __must_check __copy_user_flushcache(void *to, const void __user *from, unsigned long n); -static inline int __copy_from_user_flushcache(void *dst, const void __user *src, unsigned size) +static inline size_t copy_from_user_flushcache(void *dst, const void __user *src, size_t size) { kasan_check_write(dst, size); return __copy_user_flushcache(dst, __uaccess_mask_ptr(src), size); diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index 929f7050c73a6..5ef59b1f6d6d5 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -407,8 +407,7 @@ copy_mc_to_user(void __user *to, const void *from, unsigned long n) } #endif -extern long __copy_from_user_flushcache(void *dst, const void __user *src, - unsigned size); +extern size_t copy_from_user_flushcache(void *dst, const void __user *src, size_t size); static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len) { diff --git a/arch/powerpc/lib/pmem.c b/arch/powerpc/lib/pmem.c index 4e724c4c01add..0f0f2d851ac67 100644 --- a/arch/powerpc/lib/pmem.c +++ b/arch/powerpc/lib/pmem.c @@ -66,15 +66,16 @@ EXPORT_SYMBOL_GPL(arch_invalidate_pmem); /* * CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE symbols */ -long __copy_from_user_flushcache(void *dest, const void __user *src, - unsigned size) +size_t copy_from_user_flushcache(void *dest, const void __user *src, + size_t size) { - unsigned long copied, start = (unsigned long) dest; + unsigned long not_copied, start = (unsigned long) dest; - copied = __copy_from_user(dest, src, size); + src = mask_user_address(src); + not_copied = __copy_from_user(dest, src, size); clean_pmem_range(start, start + size); - return copied; + return not_copied; } void memcpy_flushcache(void *dest, const void *src, size_t size) diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h index 52189450b82ea..d7daec6dd1684 100644 --- a/arch/x86/include/asm/uaccess_64.h +++ b/arch/x86/include/asm/uaccess_64.h @@ -149,7 +149,7 @@ raw_copy_to_user(void __user *dst, const void *src, unsigned long size) #define copy_to_nontemporal copy_to_nontemporal extern size_t copy_to_nontemporal(void *dst, const void *src, size_t size); -extern long __copy_user_flushcache(void *dst, const void __user *src, unsigned size); +extern size_t copy_user_flushcache(void *dst, const void __user *src, size_t size); static inline int copy_from_user_inatomic_nontemporal(void *dst, const void __user *src, @@ -164,11 +164,11 @@ copy_from_user_inatomic_nontemporal(void *dst, const void __user *src, return ret; } -static inline int -__copy_from_user_flushcache(void *dst, const void __user *src, unsigned size) +static inline size_t +copy_from_user_flushcache(void *dst, const void __user *src, size_t size) { kasan_check_write(dst, size); - return __copy_user_flushcache(dst, src, size); + return copy_user_flushcache(dst, src, size); } /* diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c index 348c9275edce1..c47d8cd0e243b 100644 --- a/arch/x86/lib/usercopy_64.c +++ b/arch/x86/lib/usercopy_64.c @@ -43,14 +43,14 @@ void arch_wb_cache_pmem(void *addr, size_t size) } EXPORT_SYMBOL_GPL(arch_wb_cache_pmem); -long __copy_user_flushcache(void *dst, const void __user *src, unsigned size) +size_t copy_user_flushcache(void *dst, const void __user *src, size_t size) { unsigned long flushed, dest = (unsigned long) dst; - long rc; + unsigned long rc; - stac(); + src = masked_user_access_begin(src); rc = copy_to_nontemporal(dst, (__force const void *)src, size); - clac(); + user_access_end(); /* * copy_to_nontemporal() uses non-temporal stores for the bulk diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 7e81fea459e46..4bc7c19337558 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -284,7 +284,7 @@ static __always_inline size_t copy_from_user_iter_flushcache(void __user *iter_from, size_t progress, size_t len, void *to, void *priv2) { - return __copy_from_user_flushcache(to + progress, iter_from, len); + return copy_from_user_flushcache(to + progress, iter_from, len); } static __always_inline