block: Abstract out bvec iterator

Immutable biovecs are going to require an explicit iterator. To
implement immutable bvecs, a later patch is going to add a bi_bvec_done
member to this struct; for now, this patch effectively just renames
things.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: Benny Halevy <bhalevy@tonian.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: xfs@oss.sgi.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchand@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peng Tao <tao.peng@emc.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: fanchaoting <fanchaoting@cn.fujitsu.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Pankaj Kumar <pankaj.km@samsung.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>6

1 files changed, 39 insertions, 36 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 1e5a540995e9..db3b9d7314f1 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -229,7 +229,7 @@ static void call_bio_endio(struct r1bio *r1_bio)
 	int done;
 	struct r1conf *conf = r1_bio->mddev->private;
 	sector_t start_next_window = r1_bio->start_next_window;
-	sector_t bi_sector = bio->bi_sector;
+	sector_t bi_sector = bio->bi_iter.bi_sector;
 
 	if (bio->bi_phys_segments) {
 		unsigned long flags;
@@ -265,9 +265,8 @@ static void raid_end_bio_io(struct r1bio *r1_bio)
 	if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
 		pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
 			 (bio_data_dir(bio) == WRITE) ? "write" : "read",
-			 (unsigned long long) bio->bi_sector,
-			 (unsigned long long) bio->bi_sector +
-			 bio_sectors(bio) - 1);
+			 (unsigned long long) bio->bi_iter.bi_sector,
+			 (unsigned long long) bio_end_sector(bio) - 1);
 
 		call_bio_endio(r1_bio);
 	}
@@ -466,9 +465,8 @@ static void raid1_end_write_request(struct bio *bio, int error)
 				struct bio *mbio = r1_bio->master_bio;
 				pr_debug("raid1: behind end write sectors"
 					 " %llu-%llu\n",
-					 (unsigned long long) mbio->bi_sector,
-					 (unsigned long long) mbio->bi_sector +
-					 bio_sectors(mbio) - 1);
+					 (unsigned long long) mbio->bi_iter.bi_sector,
+					 (unsigned long long) bio_end_sector(mbio) - 1);
 				call_bio_endio(r1_bio);
 			}
 		}
@@ -875,7 +873,7 @@ static bool need_to_wait_for_sync(struct r1conf *conf, struct bio *bio)
 		else if ((conf->next_resync - RESYNC_WINDOW_SECTORS
 				>= bio_end_sector(bio)) ||
 			 (conf->next_resync + NEXT_NORMALIO_DISTANCE
-				<= bio->bi_sector))
+				<= bio->bi_iter.bi_sector))
 			wait = false;
 		else
 			wait = true;
@@ -913,19 +911,19 @@ static sector_t wait_barrier(struct r1conf *conf, struct bio *bio)
 
 	if (bio && bio_data_dir(bio) == WRITE) {
 		if (conf->next_resync + NEXT_NORMALIO_DISTANCE
-		    <= bio->bi_sector) {
+		    <= bio->bi_iter.bi_sector) {
 			if (conf->start_next_window == MaxSector)
 				conf->start_next_window =
 					conf->next_resync +
 					NEXT_NORMALIO_DISTANCE;
 
 			if ((conf->start_next_window + NEXT_NORMALIO_DISTANCE)
-			    <= bio->bi_sector)
+			    <= bio->bi_iter.bi_sector)
 				conf->next_window_requests++;
 			else
 				conf->current_window_requests++;
 		}
-		if (bio->bi_sector >= conf->start_next_window)
+		if (bio->bi_iter.bi_sector >= conf->start_next_window)
 			sector = conf->start_next_window;
 	}
 
@@ -1028,7 +1026,8 @@ do_sync_io:
 		if (bvecs[i].bv_page)
 			put_page(bvecs[i].bv_page);
 	kfree(bvecs);
-	pr_debug("%dB behind alloc failed, doing sync I/O\n", bio->bi_size);
+	pr_debug("%dB behind alloc failed, doing sync I/O\n",
+		 bio->bi_iter.bi_size);
 }
 
 struct raid1_plug_cb {
@@ -1108,7 +1107,7 @@ static void make_request(struct mddev *mddev, struct bio * bio)
 
 	if (bio_data_dir(bio) == WRITE &&
 	    bio_end_sector(bio) > mddev->suspend_lo &&
-	    bio->bi_sector < mddev->suspend_hi) {
+	    bio->bi_iter.bi_sector < mddev->suspend_hi) {
 		/* As the suspend_* range is controlled by
 		 * userspace, we want an interruptible
 		 * wait.
@@ -1119,7 +1118,7 @@ static void make_request(struct mddev *mddev, struct bio * bio)
 			prepare_to_wait(&conf->wait_barrier,
 					&w, TASK_INTERRUPTIBLE);
 			if (bio_end_sector(bio) <= mddev->suspend_lo ||
-			    bio->bi_sector >= mddev->suspend_hi)
+			    bio->bi_iter.bi_sector >= mddev->suspend_hi)
 				break;
 			schedule();
 		}
@@ -1141,7 +1140,7 @@ static void make_request(struct mddev *mddev, struct bio * bio)
 	r1_bio->sectors = bio_sectors(bio);
 	r1_bio->state = 0;
 	r1_bio->mddev = mddev;
-	r1_bio->sector = bio->bi_sector;
+	r1_bio->sector = bio->bi_iter.bi_sector;
 
 	/* We might need to issue multiple reads to different
 	 * devices if there are bad blocks around, so we keep
@@ -1181,12 +1180,13 @@ read_again:
 		r1_bio->read_disk = rdisk;
 
 		read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev);
-		bio_trim(read_bio, r1_bio->sector - bio->bi_sector,
+		bio_trim(read_bio, r1_bio->sector - bio->bi_iter.bi_sector,
 			 max_sectors);
 
 		r1_bio->bios[rdisk] = read_bio;
 
-		read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset;
+		read_bio->bi_iter.bi_sector = r1_bio->sector +
+			mirror->rdev->data_offset;
 		read_bio->bi_bdev = mirror->rdev->bdev;
 		read_bio->bi_end_io = raid1_end_read_request;
 		read_bio->bi_rw = READ | do_sync;
@@ -1198,7 +1198,7 @@ read_again:
 			 */
 
 			sectors_handled = (r1_bio->sector + max_sectors
-					   - bio->bi_sector);
+					   - bio->bi_iter.bi_sector);
 			r1_bio->sectors = max_sectors;
 			spin_lock_irq(&conf->device_lock);
 			if (bio->bi_phys_segments == 0)
@@ -1219,7 +1219,8 @@ read_again:
 			r1_bio->sectors = bio_sectors(bio) - sectors_handled;
 			r1_bio->state = 0;
 			r1_bio->mddev = mddev;
-			r1_bio->sector = bio->bi_sector + sectors_handled;
+			r1_bio->sector = bio->bi_iter.bi_sector +
+				sectors_handled;
 			goto read_again;
 		} else
 			generic_make_request(read_bio);
@@ -1322,7 +1323,7 @@ read_again:
 			if (r1_bio->bios[j])
 				rdev_dec_pending(conf->mirrors[j].rdev, mddev);
 		r1_bio->state = 0;
-		allow_barrier(conf, start_next_window, bio->bi_sector);
+		allow_barrier(conf, start_next_window, bio->bi_iter.bi_sector);
 		md_wait_for_blocked_rdev(blocked_rdev, mddev);
 		start_next_window = wait_barrier(conf, bio);
 		/*
@@ -1349,7 +1350,7 @@ read_again:
 			bio->bi_phys_segments++;
 		spin_unlock_irq(&conf->device_lock);
 	}
-	sectors_handled = r1_bio->sector + max_sectors - bio->bi_sector;
+	sectors_handled = r1_bio->sector + max_sectors - bio->bi_iter.bi_sector;
 
 	atomic_set(&r1_bio->remaining, 1);
 	atomic_set(&r1_bio->behind_remaining, 0);
@@ -1361,7 +1362,7 @@ read_again:
 			continue;
 
 		mbio = bio_clone_mddev(bio, GFP_NOIO, mddev);
-		bio_trim(mbio, r1_bio->sector - bio->bi_sector, max_sectors);
+		bio_trim(mbio, r1_bio->sector - bio->bi_iter.bi_sector, max_sectors);
 
 		if (first_clone) {
 			/* do behind I/O ?
@@ -1395,7 +1396,7 @@ read_again:
 
 		r1_bio->bios[i] = mbio;
 
-		mbio->bi_sector	= (r1_bio->sector +
+		mbio->bi_iter.bi_sector	= (r1_bio->sector +
 				   conf->mirrors[i].rdev->data_offset);
 		mbio->bi_bdev = conf->mirrors[i].rdev->bdev;
 		mbio->bi_end_io	= raid1_end_write_request;
@@ -1435,7 +1436,7 @@ read_again:
 		r1_bio->sectors = bio_sectors(bio) - sectors_handled;
 		r1_bio->state = 0;
 		r1_bio->mddev = mddev;
-		r1_bio->sector = bio->bi_sector + sectors_handled;
+		r1_bio->sector = bio->bi_iter.bi_sector + sectors_handled;
 		goto retry_write;
 	}
 
@@ -1959,14 +1960,14 @@ static int process_checks(struct r1bio *r1_bio)
 		/* fixup the bio for reuse */
 		bio_reset(b);
 		b->bi_vcnt = vcnt;
-		b->bi_size = r1_bio->sectors << 9;
-		b->bi_sector = r1_bio->sector +
+		b->bi_iter.bi_size = r1_bio->sectors << 9;
+		b->bi_iter.bi_sector = r1_bio->sector +
 			conf->mirrors[i].rdev->data_offset;
 		b->bi_bdev = conf->mirrors[i].rdev->bdev;
 		b->bi_end_io = end_sync_read;
 		b->bi_private = r1_bio;
 
-		size = b->bi_size;
+		size = b->bi_iter.bi_size;
 		for (j = 0; j < vcnt ; j++) {
 			struct bio_vec *bi;
 			bi = &b->bi_io_vec[j];
@@ -2221,11 +2222,11 @@ static int narrow_write_error(struct r1bio *r1_bio, int i)
 		}
 
 		wbio->bi_rw = WRITE;
-		wbio->bi_sector = r1_bio->sector;
-		wbio->bi_size = r1_bio->sectors << 9;
+		wbio->bi_iter.bi_sector = r1_bio->sector;
+		wbio->bi_iter.bi_size = r1_bio->sectors << 9;
 
 		bio_trim(wbio, sector - r1_bio->sector, sectors);
-		wbio->bi_sector += rdev->data_offset;
+		wbio->bi_iter.bi_sector += rdev->data_offset;
 		wbio->bi_bdev = rdev->bdev;
 		if (submit_bio_wait(WRITE, wbio) == 0)
 			/* failure! */
@@ -2339,7 +2340,8 @@ read_more:
 		}
 		r1_bio->read_disk = disk;
 		bio = bio_clone_mddev(r1_bio->master_bio, GFP_NOIO, mddev);
-		bio_trim(bio, r1_bio->sector - bio->bi_sector, max_sectors);
+		bio_trim(bio, r1_bio->sector - bio->bi_iter.bi_sector,
+			 max_sectors);
 		r1_bio->bios[r1_bio->read_disk] = bio;
 		rdev = conf->mirrors[disk].rdev;
 		printk_ratelimited(KERN_ERR
@@ -2348,7 +2350,7 @@ read_more:
 				   mdname(mddev),
 				   (unsigned long long)r1_bio->sector,
 				   bdevname(rdev->bdev, b));
-		bio->bi_sector = r1_bio->sector + rdev->data_offset;
+		bio->bi_iter.bi_sector = r1_bio->sector + rdev->data_offset;
 		bio->bi_bdev = rdev->bdev;
 		bio->bi_end_io = raid1_end_read_request;
 		bio->bi_rw = READ | do_sync;
@@ -2357,7 +2359,7 @@ read_more:
 			/* Drat - have to split this up more */
 			struct bio *mbio = r1_bio->master_bio;
 			int sectors_handled = (r1_bio->sector + max_sectors
-					       - mbio->bi_sector);
+					       - mbio->bi_iter.bi_sector);
 			r1_bio->sectors = max_sectors;
 			spin_lock_irq(&conf->device_lock);
 			if (mbio->bi_phys_segments == 0)
@@ -2375,7 +2377,8 @@ read_more:
 			r1_bio->state = 0;
 			set_bit(R1BIO_ReadError, &r1_bio->state);
 			r1_bio->mddev = mddev;
-			r1_bio->sector = mbio->bi_sector + sectors_handled;
+			r1_bio->sector = mbio->bi_iter.bi_sector +
+				sectors_handled;
 
 			goto read_more;
 		} else
@@ -2599,7 +2602,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp
 		}
 		if (bio->bi_end_io) {
 			atomic_inc(&rdev->nr_pending);
-			bio->bi_sector = sector_nr + rdev->data_offset;
+			bio->bi_iter.bi_sector = sector_nr + rdev->data_offset;
 			bio->bi_bdev = rdev->bdev;
 			bio->bi_private = r1_bio;
 		}
@@ -2699,7 +2702,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp
 							continue;
 						/* remove last page from this bio */
 						bio->bi_vcnt--;
-						bio->bi_size -= len;
+						bio->bi_iter.bi_size -= len;
 						bio->bi_flags &= ~(1<< BIO_SEG_VALID);
 					}
 					goto bio_full;