diff --git a/lib/iov_iter.c b/lib/iov_iter.c index d67c8288d95d..9e8c7386b3a0 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -144,7 +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; @@ -175,6 +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); @@ -193,6 +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++; @@ -225,7 +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; @@ -256,6 +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); @@ -274,6 +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++;