From d0b2f91bede3bd5e3d24dd6803e56eee959c1797 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Thu, 20 Oct 2016 00:10:27 -0300 Subject: Linux-libre 4.8.2-gnu --- lib/iov_iter.c | 53 +++++++++++++++++++++-------------------------------- 1 file changed, 21 insertions(+), 32 deletions(-) (limited to 'lib/iov_iter.c') diff --git a/lib/iov_iter.c b/lib/iov_iter.c index eaaf73032..7e3138cfc 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -56,37 +56,24 @@ n = wanted; \ } -#define iterate_bvec(i, n, __v, __p, skip, STEP) { \ - size_t wanted = n; \ - __p = i->bvec; \ - __v.bv_len = min_t(size_t, n, __p->bv_len - skip); \ - if (likely(__v.bv_len)) { \ - __v.bv_page = __p->bv_page; \ - __v.bv_offset = __p->bv_offset + skip; \ - (void)(STEP); \ - skip += __v.bv_len; \ - n -= __v.bv_len; \ - } \ - while (unlikely(n)) { \ - __p++; \ - __v.bv_len = min_t(size_t, n, __p->bv_len); \ - if (unlikely(!__v.bv_len)) \ +#define iterate_bvec(i, n, __v, __bi, skip, STEP) { \ + struct bvec_iter __start; \ + __start.bi_size = n; \ + __start.bi_bvec_done = skip; \ + __start.bi_idx = 0; \ + for_each_bvec(__v, i->bvec, __bi, __start) { \ + if (!__v.bv_len) \ continue; \ - __v.bv_page = __p->bv_page; \ - __v.bv_offset = __p->bv_offset; \ (void)(STEP); \ - skip = __v.bv_len; \ - n -= __v.bv_len; \ } \ - n = wanted; \ } #define iterate_all_kinds(i, n, v, I, B, K) { \ size_t skip = i->iov_offset; \ if (unlikely(i->type & ITER_BVEC)) { \ - const struct bio_vec *bvec; \ struct bio_vec v; \ - iterate_bvec(i, n, v, bvec, skip, (B)) \ + struct bvec_iter __bi; \ + iterate_bvec(i, n, v, __bi, skip, (B)) \ } else if (unlikely(i->type & ITER_KVEC)) { \ const struct kvec *kvec; \ struct kvec v; \ @@ -104,15 +91,13 @@ if (i->count) { \ size_t skip = i->iov_offset; \ if (unlikely(i->type & ITER_BVEC)) { \ - const struct bio_vec *bvec; \ + const struct bio_vec *bvec = i->bvec; \ struct bio_vec v; \ - iterate_bvec(i, n, v, bvec, skip, (B)) \ - if (skip == bvec->bv_len) { \ - bvec++; \ - skip = 0; \ - } \ - i->nr_segs -= bvec - i->bvec; \ - i->bvec = bvec; \ + struct bvec_iter __bi; \ + iterate_bvec(i, n, v, __bi, skip, (B)) \ + i->bvec = __bvec_iter_bvec(i->bvec, __bi); \ + i->nr_segs -= i->bvec - bvec; \ + skip = __bi.bi_bvec_done; \ } else if (unlikely(i->type & ITER_KVEC)) { \ const struct kvec *kvec; \ struct kvec v; \ @@ -159,7 +144,7 @@ static size_t copy_page_to_iter_iovec(struct page *page, size_t offset, size_t b buf = iov->iov_base + skip; copy = min(bytes, iov->iov_len - skip); - if (!fault_in_pages_writeable(buf, copy)) { + if (IS_ENABLED(CONFIG_HIGHMEM) && !fault_in_pages_writeable(buf, copy)) { kaddr = kmap_atomic(page); from = kaddr + offset; @@ -190,6 +175,7 @@ static size_t copy_page_to_iter_iovec(struct page *page, size_t offset, size_t b copy = min(bytes, iov->iov_len - skip); } /* Too bad - revert to non-atomic kmap */ + kaddr = kmap(page); from = kaddr + offset; left = __copy_to_user(buf, from, copy); @@ -208,6 +194,7 @@ static size_t copy_page_to_iter_iovec(struct page *page, size_t offset, size_t b bytes -= copy; } kunmap(page); + done: if (skip == iov->iov_len) { iov++; @@ -240,7 +227,7 @@ static size_t copy_page_from_iter_iovec(struct page *page, size_t offset, size_t buf = iov->iov_base + skip; copy = min(bytes, iov->iov_len - skip); - if (!fault_in_pages_readable(buf, copy)) { + if (IS_ENABLED(CONFIG_HIGHMEM) && !fault_in_pages_readable(buf, copy)) { kaddr = kmap_atomic(page); to = kaddr + offset; @@ -271,6 +258,7 @@ static size_t copy_page_from_iter_iovec(struct page *page, size_t offset, size_t copy = min(bytes, iov->iov_len - skip); } /* Too bad - revert to non-atomic kmap */ + kaddr = kmap(page); to = kaddr + offset; left = __copy_from_user(to, buf, copy); @@ -289,6 +277,7 @@ static size_t copy_page_from_iter_iovec(struct page *page, size_t offset, size_t bytes -= copy; } kunmap(page); + done: if (skip == iov->iov_len) { iov++; -- cgit v1.2.3-54-g00ecf