From 62a8067a7f35dba2de501c9cb00e4cf36da90bc0 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 4 Apr 2014 23:12:29 -0400 Subject: bio_vec-backed iov_iter New variant of iov_iter - ITER_BVEC in iter->type, backed with bio_vec array instead of iovec one. Primitives taught to deal with such beasts, __swap_write() switched to using that kind of iov_iter. Note that bio_vec is just a triple - there's nothing block-specific about it. I've left the definition where it was, but took it from under ifdef CONFIG_BLOCK. Next target: ->splice_write()... Signed-off-by: Al Viro --- mm/page_io.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) (limited to 'mm/page_io.c') diff --git a/mm/page_io.c b/mm/page_io.c index 313bfedb75d1..33bb38c4aad7 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -259,23 +259,28 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc, struct kiocb kiocb; struct file *swap_file = sis->swap_file; struct address_space *mapping = swap_file->f_mapping; - struct iovec iov = { - .iov_base = kmap(page), - .iov_len = PAGE_SIZE, + struct bio_vec bv = { + .bv_page = page, + .bv_len = PAGE_SIZE, + .bv_offset = 0 + }; + struct iov_iter from = { + .type = ITER_BVEC | WRITE, + .count = PAGE_SIZE, + .iov_offset = 0, + .nr_segs = 1, + .bvec = &bv }; - struct iov_iter from; init_sync_kiocb(&kiocb, swap_file); kiocb.ki_pos = page_file_offset(page); kiocb.ki_nbytes = PAGE_SIZE; - iov_iter_init(&from, KERNEL_WRITE, &iov, 1, PAGE_SIZE); set_page_writeback(page); unlock_page(page); - ret = mapping->a_ops->direct_IO(KERNEL_WRITE, + ret = mapping->a_ops->direct_IO(ITER_BVEC | WRITE, &kiocb, &from, kiocb.ki_pos); - kunmap(page); if (ret == PAGE_SIZE) { count_vm_event(PSWPOUT); ret = 0; -- cgit v1.2.3