diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h index 9ea58c0e7cfb..ce0c28495f9a 100644 --- a/arch/powerpc/include/asm/checksum.h +++ b/arch/powerpc/include/asm/checksum.h @@ -57,6 +57,9 @@ extern __wsum csum_partial_copy_generic(const void *src, void *dst, #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER extern __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr); +#define HAVE_CSUM_COPY_USER +extern __wsum csum_and_copy_to_user(const void *src, void __user *dst, + int len, __wsum sum, int *err_ptr); #else /* * the same as csum_partial, but copies from src to dst while it diff --git a/arch/powerpc/lib/checksum_wrappers_64.c b/arch/powerpc/lib/checksum_wrappers_64.c index 614cff1a8e0e..769b817fbb32 100644 --- a/arch/powerpc/lib/checksum_wrappers_64.c +++ b/arch/powerpc/lib/checksum_wrappers_64.c @@ -63,3 +63,40 @@ out: return (__force __wsum)csum; } EXPORT_SYMBOL(csum_and_copy_from_user); + +__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len, + __wsum sum, int *err_ptr) +{ + unsigned int csum; + + might_sleep(); + + *err_ptr = 0; + + if (!len) { + csum = 0; + goto out; + } + + if (unlikely((len < 0) || !access_ok(VERIFY_WRITE, dst, len))) { + *err_ptr = -EFAULT; + csum = -1; /* invalid checksum */ + goto out; + } + + csum = csum_partial_copy_generic(src, (void __force *)dst, + len, sum, NULL, err_ptr); + + if (unlikely(*err_ptr)) { + csum = csum_partial(src, len, sum); + + if (copy_to_user(dst, src, len)) { + *err_ptr = -EFAULT; + csum = -1; /* invalid checksum */ + } + } + +out: + return (__force __wsum)csum; +} +EXPORT_SYMBOL(csum_and_copy_to_user);