[PATCH v1 04/15] block: introduce BIO_VEC_INIT() macro to initialize bio_vec structure

[jglisse@redhat.com]

From: Jérôme Glisse <jglisse@redhat.com>

This add a macro to initialize bio_vec structure. We want to convert
all initialization with that macro so that it is easier to change the
bvec->page fields in latter patch.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-block@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Sage Weil <sage@redhat.com>
Cc: Alex Elder <elder@kernel.org>
Cc: ceph-devel@vger.kernel.org
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Steve French <sfrench@samba.org>
Cc: linux-cifs@vger.kernel.org
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Martin Brandenburg <martin@omnibond.com>
Cc: devel@lists.orangefs.org
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: v9fs-developer@lists.sourceforge.net
---
 block/blk-integrity.c | 4 ++--
 block/blk-merge.c     | 2 +-
 fs/9p/vfs_addr.c      | 2 +-
 fs/ceph/file.c        | 8 +++-----
 fs/cifs/connect.c     | 4 ++--
 fs/orangefs/inode.c   | 2 +-
 include/linux/bvec.h  | 2 ++
 mm/page_io.c          | 6 +-----
 net/ceph/messenger.c  | 6 +-----
 9 files changed, 14 insertions(+), 22 deletions(-)

diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index d1ab089e0919..916a5406649d 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -40,7 +40,7 @@
  */
 int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio)
 {
-	struct bio_vec iv, ivprv = { NULL };
+	struct bio_vec iv, ivprv = BIO_VEC_INIT(NULL, 0, 0);
 	unsigned int segments = 0;
 	unsigned int seg_size = 0;
 	struct bvec_iter iter;
@@ -82,7 +82,7 @@ EXPORT_SYMBOL(blk_rq_count_integrity_sg);
 int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
 			    struct scatterlist *sglist)
 {
-	struct bio_vec iv, ivprv = { NULL };
+	struct bio_vec iv, ivprv = BIO_VEC_INIT(NULL, 0, 0);
 	struct scatterlist *sg = NULL;
 	unsigned int segments = 0;
 	struct bvec_iter iter;
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 1c9d4f0f96ea..c355fb9e9e8e 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -447,7 +447,7 @@ void blk_recount_segments(struct request_queue *q, struct bio *bio)
 static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio,
 				   struct bio *nxt)
 {
-	struct bio_vec end_bv = { NULL }, nxt_bv;
+	struct bio_vec end_bv = BIO_VEC_INIT(NULL, 0, 0), nxt_bv;
 
 	if (bio->bi_seg_back_size + nxt->bi_seg_front_size >
 	    queue_max_segment_size(q))
diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
index 0bcbcc20f769..b626b28f0ce9 100644
--- a/fs/9p/vfs_addr.c
+++ b/fs/9p/vfs_addr.c
@@ -53,7 +53,7 @@
 static int v9fs_fid_readpage(struct p9_fid *fid, struct page *page)
 {
 	struct inode *inode = page->mapping->host;
-	struct bio_vec bvec = {.bv_page = page, .bv_len = PAGE_SIZE};
+	struct bio_vec bvec = BIO_VEC_INIT(page, PAGE_SIZE, 0);
 	struct iov_iter to;
 	int retval, err;
 
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 9f53c3d99304..d3c8035335a2 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -100,11 +100,9 @@ static ssize_t __iter_get_bvecs(struct iov_iter *iter, size_t maxsize,
 		size += bytes;
 
 		for ( ; bytes; idx++, bvec_idx++) {
-			struct bio_vec bv = {
-				.bv_page = pages[idx],
-				.bv_len = min_t(int, bytes, PAGE_SIZE - start),
-				.bv_offset = start,
-			};
+			struct bio_vec bv = BIO_VEC_INIT(pages[idx],
+				min_t(int, bytes, PAGE_SIZE - start),
+				start);
 
 			bvecs[bvec_idx] = bv;
 			bytes -= bv.bv_len;
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 4c0e44489f21..86438f3933a9 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -809,8 +809,8 @@ cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
 	unsigned int page_offset, unsigned int to_read)
 {
 	struct msghdr smb_msg;
-	struct bio_vec bv = {
-		.bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
+	struct bio_vec bv = BIO_VEC_INIT(page, to_read, page_offset);
+
 	iov_iter_bvec(&smb_msg.msg_iter, READ, &bv, 1, to_read);
 	return cifs_readv_from_socket(server, &smb_msg);
 }
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index c3334eca18c7..5ebd2da4c093 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -23,7 +23,7 @@ static int read_one_page(struct page *page)
 	const __u32 blocksize = PAGE_SIZE;
 	const __u32 blockbits = PAGE_SHIFT;
 	struct iov_iter to;
-	struct bio_vec bv = {.bv_page = page, .bv_len = PAGE_SIZE};
+	struct bio_vec bv = BIO_VEC_INIT(page, PAGE_SIZE, 0);
 
 	iov_iter_bvec(&to, READ, &bv, 1, PAGE_SIZE);
 
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 44866555258a..8f8fb528ce53 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -70,6 +70,8 @@ static inline struct page *bvec_nth_page(struct page *page, int idx)
  * various member access, note that bio_data should of course not be used
  * on highmem page vectors
  */
+#define BIO_VEC_INIT(p, l, o) {.bv_page = (p), .bv_len = (l), .bv_offset = (o)}
+
 #define __bvec_iter_bvec(bvec, iter)	(&(bvec)[(iter).bi_idx])
 
 /* multi-page (mp_bvec) helpers */
diff --git a/mm/page_io.c b/mm/page_io.c
index 2e8019d0e048..6b3be0445c61 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -287,11 +287,7 @@ 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 bio_vec bv = {
-			.bv_page = page,
-			.bv_len  = PAGE_SIZE,
-			.bv_offset = 0
-		};
+		struct bio_vec bv = BIO_VEC_INIT(page, PAGE_SIZE, 0);
 		struct iov_iter from;
 
 		iov_iter_bvec(&from, WRITE, &bv, 1, PAGE_SIZE);
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 3083988ce729..3e16187491d8 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -523,11 +523,7 @@ static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len)
 static int ceph_tcp_recvpage(struct socket *sock, struct page *page,
 		     int page_offset, size_t length)
 {
-	struct bio_vec bvec = {
-		.bv_page = page,
-		.bv_offset = page_offset,
-		.bv_len = length
-	};
+	struct bio_vec bvec = BIO_VEC_INIT(page, length, page_offset);
 	struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
 	int r;
 
-- 
2.20.1