Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754857AbaLIW5f (ORCPT ); Tue, 9 Dec 2014 17:57:35 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:37458 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753951AbaLIWuj (ORCPT ); Tue, 9 Dec 2014 17:50:39 -0500 From: Al Viro To: David Miller Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 06/25] iov_iter.c: convert iov_iter_zero() to iterate_and_advance Date: Tue, 9 Dec 2014 22:50:19 +0000 Message-Id: <1418165438-2205-6-git-send-email-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <20141209224928.GL22149@ZenIV.linux.org.uk> References: <20141209224928.GL22149@ZenIV.linux.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Al Viro Signed-off-by: Al Viro --- mm/iov_iter.c | 98 ++++++++--------------------------------------------------- 1 file changed, 12 insertions(+), 86 deletions(-) diff --git a/mm/iov_iter.c b/mm/iov_iter.c index 3214b9b..39ad713 100644 --- a/mm/iov_iter.c +++ b/mm/iov_iter.c @@ -349,50 +349,6 @@ done: return wanted - bytes; } -static size_t zero_iovec(size_t bytes, struct iov_iter *i) -{ - size_t skip, copy, left, wanted; - const struct iovec *iov; - char __user *buf; - - if (unlikely(bytes > i->count)) - bytes = i->count; - - if (unlikely(!bytes)) - return 0; - - wanted = bytes; - iov = i->iov; - skip = i->iov_offset; - buf = iov->iov_base + skip; - copy = min(bytes, iov->iov_len - skip); - - left = __clear_user(buf, copy); - copy -= left; - skip += copy; - bytes -= copy; - - while (unlikely(!left && bytes)) { - iov++; - buf = iov->iov_base; - copy = min(bytes, iov->iov_len); - left = __clear_user(buf, copy); - copy -= left; - skip = copy; - bytes -= copy; - } - - if (skip == iov->iov_len) { - iov++; - skip = 0; - } - i->count -= wanted - bytes; - i->nr_segs -= iov - i->iov; - i->iov = iov; - i->iov_offset = skip; - return wanted - bytes; -} - /* * Fault in the first iovec of the given iov_iter, to a maximum length * of bytes. Returns 0 on success, or non-zero if the memory could not be @@ -548,43 +504,6 @@ static size_t copy_page_from_iter_bvec(struct page *page, size_t offset, return wanted; } -static size_t zero_bvec(size_t bytes, struct iov_iter *i) -{ - size_t skip, copy, wanted; - const struct bio_vec *bvec; - - if (unlikely(bytes > i->count)) - bytes = i->count; - - if (unlikely(!bytes)) - return 0; - - wanted = bytes; - bvec = i->bvec; - skip = i->iov_offset; - copy = min_t(size_t, bytes, bvec->bv_len - skip); - - memzero_page(bvec->bv_page, skip + bvec->bv_offset, copy); - skip += copy; - bytes -= copy; - while (bytes) { - bvec++; - copy = min(bytes, (size_t)bvec->bv_len); - memzero_page(bvec->bv_page, bvec->bv_offset, copy); - skip = copy; - bytes -= copy; - } - if (skip == bvec->bv_len) { - bvec++; - skip = 0; - } - i->count -= wanted - bytes; - i->nr_segs -= bvec - i->bvec; - i->bvec = bvec; - i->iov_offset = skip; - return wanted - bytes; -} - size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes, struct iov_iter *i) { @@ -625,11 +544,18 @@ EXPORT_SYMBOL(copy_from_iter); size_t iov_iter_zero(size_t bytes, struct iov_iter *i) { - if (i->type & ITER_BVEC) { - return zero_bvec(bytes, i); - } else { - return zero_iovec(bytes, i); - } + if (unlikely(bytes > i->count)) + bytes = i->count; + + if (unlikely(!bytes)) + return 0; + + iterate_and_advance(i, bytes, v, + __clear_user(v.iov_base, v.iov_len), + memzero_page(v.bv_page, v.bv_offset, v.bv_len) + ) + + return bytes; } EXPORT_SYMBOL(iov_iter_zero); -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/