diff options
Diffstat (limited to 'arch/powerpc/lib/checksum_wrappers_64.c')
-rw-r--r-- | arch/powerpc/lib/checksum_wrappers_64.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/powerpc/lib/checksum_wrappers_64.c b/arch/powerpc/lib/checksum_wrappers_64.c new file mode 100644 index 00000000000..769b817fbb3 --- /dev/null +++ b/arch/powerpc/lib/checksum_wrappers_64.c @@ -0,0 +1,102 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2010 + * + * Author: Anton Blanchard <anton@au.ibm.com> + */ +#include <linux/module.h> +#include <linux/compiler.h> +#include <linux/types.h> +#include <asm/checksum.h> +#include <asm/uaccess.h> + +__wsum csum_and_copy_from_user(const void __user *src, void *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_READ, src, len))) { + *err_ptr = -EFAULT; + csum = (__force unsigned int)sum; + goto out; + } + + csum = csum_partial_copy_generic((void __force *)src, dst, + len, sum, err_ptr, NULL); + + if (unlikely(*err_ptr)) { + int missing = __copy_from_user(dst, src, len); + + if (missing) { + memset(dst + len - missing, 0, missing); + *err_ptr = -EFAULT; + } else { + *err_ptr = 0; + } + + csum = csum_partial(dst, len, sum); + } + +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); |