1 files changed, 131 insertions, 54 deletions

diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c
index e6d9e37fa24..645c78656aa 100644
--- a/fs/nilfs2/segbuf.c
+++ b/fs/nilfs2/segbuf.c
@@ -24,10 +24,22 @@
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
 #include <linux/crc32.h>
+#include <linux/backing-dev.h>
 #include "page.h"
 #include "segbuf.h"
 
 
+struct nilfs_write_info {
+	struct the_nilfs       *nilfs;
+	struct bio	       *bio;
+	int 			start, end; /* The region to be submitted */
+	int			rest_blocks;
+	int			max_pages;
+	int			nr_vecs;
+	sector_t		blocknr;
+};
+
+
 static struct kmem_cache *nilfs_segbuf_cachep;
 
 static void nilfs_segbuf_init_once(void *obj)
@@ -63,6 +75,11 @@ struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *sb)
 	INIT_LIST_HEAD(&segbuf->sb_list);
 	INIT_LIST_HEAD(&segbuf->sb_segsum_buffers);
 	INIT_LIST_HEAD(&segbuf->sb_payload_buffers);
+
+	init_completion(&segbuf->sb_bio_event);
+	atomic_set(&segbuf->sb_err, 0);
+	segbuf->sb_nbio = 0;
+
 	return segbuf;
 }
 
@@ -83,6 +100,22 @@ void nilfs_segbuf_map(struct nilfs_segment_buffer *segbuf, __u64 segnum,
 		segbuf->sb_fseg_end - segbuf->sb_pseg_start + 1;
 }
 
+/**
+ * nilfs_segbuf_map_cont - map a new log behind a given log
+ * @segbuf: new segment buffer
+ * @prev: segment buffer containing a log to be continued
+ */
+void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf,
+			   struct nilfs_segment_buffer *prev)
+{
+	segbuf->sb_segnum = prev->sb_segnum;
+	segbuf->sb_fseg_start = prev->sb_fseg_start;
+	segbuf->sb_fseg_end = prev->sb_fseg_end;
+	segbuf->sb_pseg_start = prev->sb_pseg_start + prev->sb_sum.nblocks;
+	segbuf->sb_rest_blocks =
+		segbuf->sb_fseg_end - segbuf->sb_pseg_start + 1;
+}
+
 void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *segbuf,
 				  __u64 nextnum, struct the_nilfs *nilfs)
 {
@@ -132,8 +165,6 @@ int nilfs_segbuf_reset(struct nilfs_segment_buffer *segbuf, unsigned flags,
 	segbuf->sb_sum.sumbytes = sizeof(struct nilfs_segment_summary);
 	segbuf->sb_sum.nfinfo = segbuf->sb_sum.nfileblk = 0;
 	segbuf->sb_sum.ctime = ctime;
-
-	segbuf->sb_io_error = 0;
 	return 0;
 }
 
@@ -219,7 +250,7 @@ void nilfs_segbuf_fill_in_data_crc(struct nilfs_segment_buffer *segbuf,
 	raw_sum->ss_datasum = cpu_to_le32(crc);
 }
 
-void nilfs_release_buffers(struct list_head *list)
+static void nilfs_release_buffers(struct list_head *list)
 {
 	struct buffer_head *bh, *n;
 
@@ -241,13 +272,56 @@ void nilfs_release_buffers(struct list_head *list)
 	}
 }
 
+static void nilfs_segbuf_clear(struct nilfs_segment_buffer *segbuf)
+{
+	nilfs_release_buffers(&segbuf->sb_segsum_buffers);
+	nilfs_release_buffers(&segbuf->sb_payload_buffers);
+}
+
+/*
+ * Iterators for segment buffers
+ */
+void nilfs_clear_logs(struct list_head *logs)
+{
+	struct nilfs_segment_buffer *segbuf;
+
+	list_for_each_entry(segbuf, logs, sb_list)
+		nilfs_segbuf_clear(segbuf);
+}
+
+void nilfs_truncate_logs(struct list_head *logs,
+			 struct nilfs_segment_buffer *last)
+{
+	struct nilfs_segment_buffer *n, *segbuf;
+
+	segbuf = list_prepare_entry(last, logs, sb_list);
+	list_for_each_entry_safe_continue(segbuf, n, logs, sb_list) {
+		list_del_init(&segbuf->sb_list);
+		nilfs_segbuf_clear(segbuf);
+		nilfs_segbuf_free(segbuf);
+	}
+}
+
+int nilfs_wait_on_logs(struct list_head *logs)
+{
+	struct nilfs_segment_buffer *segbuf;
+	int err;
+
+	list_for_each_entry(segbuf, logs, sb_list) {
+		err = nilfs_segbuf_wait(segbuf);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
 /*
  * BIO operations
  */
 static void nilfs_end_bio_write(struct bio *bio, int err)
 {
 	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
-	struct nilfs_write_info *wi = bio->bi_private;
+	struct nilfs_segment_buffer *segbuf = bio->bi_private;
 
 	if (err == -EOPNOTSUPP) {
 		set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
@@ -256,21 +330,22 @@ static void nilfs_end_bio_write(struct bio *bio, int err)
 	}
 
 	if (!uptodate)
-		atomic_inc(&wi->err);
+		atomic_inc(&segbuf->sb_err);
 
 	bio_put(bio);
-	complete(&wi->bio_event);
+	complete(&segbuf->sb_bio_event);
 }
 
-static int nilfs_submit_seg_bio(struct nilfs_write_info *wi, int mode)
+static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf,
+				   struct nilfs_write_info *wi, int mode)
 {
 	struct bio *bio = wi->bio;
 	int err;
 
-	if (wi->nbio > 0 && bdi_write_congested(wi->bdi)) {
-		wait_for_completion(&wi->bio_event);
-		wi->nbio--;
-		if (unlikely(atomic_read(&wi->err))) {
+	if (segbuf->sb_nbio > 0 && bdi_write_congested(wi->nilfs->ns_bdi)) {
+		wait_for_completion(&segbuf->sb_bio_event);
+		segbuf->sb_nbio--;
+		if (unlikely(atomic_read(&segbuf->sb_err))) {
 			bio_put(bio);
 			err = -EIO;
 			goto failed;
@@ -278,7 +353,7 @@ static int nilfs_submit_seg_bio(struct nilfs_write_info *wi, int mode)
 	}
 
 	bio->bi_end_io = nilfs_end_bio_write;
-	bio->bi_private = wi;
+	bio->bi_private = segbuf;
 	bio_get(bio);
 	submit_bio(mode, bio);
 	if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
@@ -286,7 +361,7 @@ static int nilfs_submit_seg_bio(struct nilfs_write_info *wi, int mode)
 		err = -EOPNOTSUPP;
 		goto failed;
 	}
-	wi->nbio++;
+	segbuf->sb_nbio++;
 	bio_put(bio);
 
 	wi->bio = NULL;
@@ -301,17 +376,15 @@ static int nilfs_submit_seg_bio(struct nilfs_write_info *wi, int mode)
 }
 
 /**
- * nilfs_alloc_seg_bio - allocate a bio for writing segment.
- * @sb: super block
- * @start: beginning disk block number of this BIO.
+ * nilfs_alloc_seg_bio - allocate a new bio for writing log
+ * @nilfs: nilfs object
+ * @start: start block number of the bio
  * @nr_vecs: request size of page vector.
  *
- * alloc_seg_bio() allocates a new BIO structure and initialize it.
- *
  * Return Value: On success, pointer to the struct bio is returned.
  * On error, NULL is returned.
  */
-static struct bio *nilfs_alloc_seg_bio(struct super_block *sb, sector_t start,
+static struct bio *nilfs_alloc_seg_bio(struct the_nilfs *nilfs, sector_t start,
 				       int nr_vecs)
 {
 	struct bio *bio;
@@ -322,36 +395,33 @@ static struct bio *nilfs_alloc_seg_bio(struct super_block *sb, sector_t start,
 			bio = bio_alloc(GFP_NOIO, nr_vecs);
 	}
 	if (likely(bio)) {
-		bio->bi_bdev = sb->s_bdev;
-		bio->bi_sector = (sector_t)start << (sb->s_blocksize_bits - 9);
+		bio->bi_bdev = nilfs->ns_bdev;
+		bio->bi_sector = start << (nilfs->ns_blocksize_bits - 9);
 	}
 	return bio;
 }
 
-void nilfs_segbuf_prepare_write(struct nilfs_segment_buffer *segbuf,
-				struct nilfs_write_info *wi)
+static void nilfs_segbuf_prepare_write(struct nilfs_segment_buffer *segbuf,
+				       struct nilfs_write_info *wi)
 {
 	wi->bio = NULL;
 	wi->rest_blocks = segbuf->sb_sum.nblocks;
-	wi->max_pages = bio_get_nr_vecs(wi->sb->s_bdev);
+	wi->max_pages = bio_get_nr_vecs(wi->nilfs->ns_bdev);
 	wi->nr_vecs = min(wi->max_pages, wi->rest_blocks);
 	wi->start = wi->end = 0;
-	wi->nbio = 0;
 	wi->blocknr = segbuf->sb_pseg_start;
-
-	atomic_set(&wi->err, 0);
-	init_completion(&wi->bio_event);
 }
 
-static int nilfs_submit_bh(struct nilfs_write_info *wi, struct buffer_head *bh,
-			   int mode)
+static int nilfs_segbuf_submit_bh(struct nilfs_segment_buffer *segbuf,
+				  struct nilfs_write_info *wi,
+				  struct buffer_head *bh, int mode)
 {
 	int len, err;
 
 	BUG_ON(wi->nr_vecs <= 0);
  repeat:
 	if (!wi->bio) {
-		wi->bio = nilfs_alloc_seg_bio(wi->sb, wi->blocknr + wi->end,
+		wi->bio = nilfs_alloc_seg_bio(wi->nilfs, wi->blocknr + wi->end,
 					      wi->nr_vecs);
 		if (unlikely(!wi->bio))
 			return -ENOMEM;
@@ -363,76 +433,83 @@ static int nilfs_submit_bh(struct nilfs_write_info *wi, struct buffer_head *bh,
 		return 0;
 	}
 	/* bio is FULL */
-	err = nilfs_submit_seg_bio(wi, mode);
+	err = nilfs_segbuf_submit_bio(segbuf, wi, mode);
 	/* never submit current bh */
 	if (likely(!err))
 		goto repeat;
 	return err;
 }
 
+/**
+ * nilfs_segbuf_write - submit write requests of a log
+ * @segbuf: buffer storing a log to be written
+ * @nilfs: nilfs object
+ *
+ * Return Value: On Success, 0 is returned. On Error, one of the following
+ * negative error code is returned.
+ *
+ * %-EIO - I/O error
+ *
+ * %-ENOMEM - Insufficient memory available.
+ */
 int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf,
-		       struct nilfs_write_info *wi)
+		       struct the_nilfs *nilfs)
 {
+	struct nilfs_write_info wi;
 	struct buffer_head *bh;
-	int res, rw = WRITE;
+	int res = 0, rw = WRITE;
+
+	wi.nilfs = nilfs;
+	nilfs_segbuf_prepare_write(segbuf, &wi);
 
 	list_for_each_entry(bh, &segbuf->sb_segsum_buffers, b_assoc_buffers) {
-		res = nilfs_submit_bh(wi, bh, rw);
+		res = nilfs_segbuf_submit_bh(segbuf, &wi, bh, rw);
 		if (unlikely(res))
 			goto failed_bio;
 	}
 
 	list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
-		res = nilfs_submit_bh(wi, bh, rw);
+		res = nilfs_segbuf_submit_bh(segbuf, &wi, bh, rw);
 		if (unlikely(res))
 			goto failed_bio;
 	}
 
-	if (wi->bio) {
+	if (wi.bio) {
 		/*
 		 * Last BIO is always sent through the following
 		 * submission.
 		 */
 		rw |= (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
-		res = nilfs_submit_seg_bio(wi, rw);
-		if (unlikely(res))
-			goto failed_bio;
+		res = nilfs_segbuf_submit_bio(segbuf, &wi, rw);
 	}
 
-	res = 0;
- out:
-	return res;
-
  failed_bio:
-	atomic_inc(&wi->err);
-	goto out;
+	return res;
 }
 
 /**
  * nilfs_segbuf_wait - wait for completion of requested BIOs
- * @wi: nilfs_write_info
+ * @segbuf: segment buffer
  *
  * Return Value: On Success, 0 is returned. On Error, one of the following
  * negative error code is returned.
  *
  * %-EIO - I/O error
  */
-int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf,
-		      struct nilfs_write_info *wi)
+int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf)
 {
 	int err = 0;
 
-	if (!wi->nbio)
+	if (!segbuf->sb_nbio)
 		return 0;
 
 	do {
-		wait_for_completion(&wi->bio_event);
-	} while (--wi->nbio > 0);
+		wait_for_completion(&segbuf->sb_bio_event);
+	} while (--segbuf->sb_nbio > 0);
 
-	if (unlikely(atomic_read(&wi->err) > 0)) {
+	if (unlikely(atomic_read(&segbuf->sb_err) > 0)) {
 		printk(KERN_ERR "NILFS: IO error writing segment\n");
 		err = -EIO;
-		segbuf->sb_io_error = 1;
 	}
 	return err;
 }