[PATCH] f2fs: allocate a bio for discarding when actually issuing it

[Jaegeuk Kim]

Let's allocate a bio when issuing discard commands later.

Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
 fs/f2fs/f2fs.h    |   4 +-
 fs/f2fs/segment.c | 113 ++++++++++++++++++++++++++++--------------------------
 2 files changed, 62 insertions(+), 55 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index a58c2e43bd2a..870bb4d9bc65 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -197,10 +197,12 @@ enum {
 struct discard_cmd {
 	struct list_head list;		/* command list */
 	struct completion wait;		/* compleation */
+	struct block_device *bdev;	/* bdev */
 	block_t lstart;			/* logical start address */
+	block_t start;			/* actual start address in dev */
 	block_t len;			/* length */
-	struct bio *bio;		/* bio */
 	int state;			/* state */
+	int error;			/* bio error */
 };
 
 struct discard_cmd_control {
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 50c65cc4645a..d8f9e6c895cd 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -636,7 +636,8 @@ static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
 }
 
 static void __add_discard_cmd(struct f2fs_sb_info *sbi,
-			struct bio *bio, block_t lstart, block_t len)
+		struct block_device *bdev, block_t lstart,
+		block_t start, block_t len)
 {
 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
 	struct list_head *cmd_list = &(dcc->discard_cmd_list);
@@ -644,9 +645,9 @@ static void __add_discard_cmd(struct f2fs_sb_info *sbi,
 
 	dc = f2fs_kmem_cache_alloc(discard_cmd_slab, GFP_NOFS);
 	INIT_LIST_HEAD(&dc->list);
-	dc->bio = bio;
-	bio->bi_private = dc;
+	dc->bdev = bdev;
 	dc->lstart = lstart;
+	dc->start = start;
 	dc->len = len;
 	dc->state = D_PREP;
 	init_completion(&dc->wait);
@@ -658,22 +659,66 @@ static void __add_discard_cmd(struct f2fs_sb_info *sbi,
 
 static void __remove_discard_cmd(struct f2fs_sb_info *sbi, struct discard_cmd *dc)
 {
-	int err = dc->bio->bi_error;
-
 	if (dc->state == D_DONE)
 		atomic_dec(&(SM_I(sbi)->dcc_info->submit_discard));
 
-	if (err == -EOPNOTSUPP)
-		err = 0;
+	if (dc->error == -EOPNOTSUPP)
+		dc->error = 0;
 
-	if (err)
+	if (dc->error)
 		f2fs_msg(sbi->sb, KERN_INFO,
-				"Issue discard failed, ret: %d", err);
-	bio_put(dc->bio);
+				"Issue discard failed, ret: %d", dc->error);
 	list_del(&dc->list);
 	kmem_cache_free(discard_cmd_slab, dc);
 }
 
+static void f2fs_submit_discard_endio(struct bio *bio)
+{
+	struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private;
+
+	complete(&dc->wait);
+	dc->error = bio->bi_error;
+	dc->state = D_DONE;
+	bio_put(bio);
+}
+
+/* this function is copied from blkdev_issue_discard from block/blk-lib.c */
+static int __submit_discard_cmd(struct discard_cmd *dc)
+{
+	struct bio *bio = NULL;
+	int err;
+
+	err = __blkdev_issue_discard(dc->bdev,
+				SECTOR_FROM_BLOCK(dc->start),
+				SECTOR_FROM_BLOCK(dc->len),
+				GFP_NOFS, 0, &bio);
+	if (!err && bio) {
+		bio->bi_private = dc;
+		bio->bi_end_io = f2fs_submit_discard_endio;
+		bio->bi_opf |= REQ_SYNC;
+		submit_bio(bio);
+	}
+	dc->state = D_SUBMIT;
+	return err;
+}
+
+static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
+		struct block_device *bdev, block_t blkstart, block_t blklen)
+{
+	block_t lblkstart = blkstart;
+
+	trace_f2fs_issue_discard(bdev, blkstart, blklen);
+
+	if (sbi->s_ndevs) {
+		int devi = f2fs_target_device_index(sbi, blkstart);
+
+		blkstart -= FDEV(devi).start_blk;
+	}
+	__add_discard_cmd(sbi, bdev, lblkstart, blkstart, blklen);
+	wake_up(&SM_I(sbi)->dcc_info->discard_wait_queue);
+	return 0;
+}
+
 /* This should be covered by global mutex, &sit_i->sentry_lock */
 void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
 {
@@ -690,8 +735,7 @@ void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
 
 		if (blkaddr == NULL_ADDR) {
 			if (dc->state == D_PREP) {
-				dc->state = D_SUBMIT;
-				submit_bio(dc->bio);
+				__submit_discard_cmd(dc);
 				atomic_inc(&dcc->submit_discard);
 			}
 			continue;
@@ -716,14 +760,6 @@ void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
 	mutex_unlock(&dcc->cmd_lock);
 }
 
-static void f2fs_submit_discard_endio(struct bio *bio)
-{
-	struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private;
-
-	complete(&dc->wait);
-	dc->state = D_DONE;
-}
-
 static int issue_discard_thread(void *data)
 {
 	struct f2fs_sb_info *sbi = data;
@@ -742,8 +778,7 @@ static int issue_discard_thread(void *data)
 	mutex_lock(&dcc->cmd_lock);
 	list_for_each_entry_safe(dc, tmp, cmd_list, list) {
 		if (dc->state == D_PREP) {
-			dc->state = D_SUBMIT;
-			submit_bio(dc->bio);
+			__submit_discard_cmd(dc);
 			atomic_inc(&dcc->submit_discard);
 			if (iter++ > DISCARD_ISSUE_RATE)
 				break;
@@ -763,36 +798,6 @@ static int issue_discard_thread(void *data)
 	goto repeat;
 }
 
-
-/* this function is copied from blkdev_issue_discard from block/blk-lib.c */
-static int __f2fs_issue_discard_async(struct f2fs_sb_info *sbi,
-		struct block_device *bdev, block_t blkstart, block_t blklen)
-{
-	struct bio *bio = NULL;
-	block_t lblkstart = blkstart;
-	int err;
-
-	trace_f2fs_issue_discard(bdev, blkstart, blklen);
-
-	if (sbi->s_ndevs) {
-		int devi = f2fs_target_device_index(sbi, blkstart);
-
-		blkstart -= FDEV(devi).start_blk;
-	}
-	err = __blkdev_issue_discard(bdev,
-				SECTOR_FROM_BLOCK(blkstart),
-				SECTOR_FROM_BLOCK(blklen),
-				GFP_NOFS, 0, &bio);
-	if (!err && bio) {
-		bio->bi_end_io = f2fs_submit_discard_endio;
-		bio->bi_opf |= REQ_SYNC;
-
-		__add_discard_cmd(sbi, bio, lblkstart, blklen);
-		wake_up(&SM_I(sbi)->dcc_info->discard_wait_queue);
-	}
-	return err;
-}
-
 #ifdef CONFIG_BLK_DEV_ZONED
 static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi,
 		struct block_device *bdev, block_t blkstart, block_t blklen)
@@ -816,7 +821,7 @@ static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi,
 	case BLK_ZONE_TYPE_CONVENTIONAL:
 		if (!blk_queue_discard(bdev_get_queue(bdev)))
 			return 0;
-		return __f2fs_issue_discard_async(sbi, bdev, lblkstart, blklen);
+		return __queue_discard_cmd(sbi, bdev, lblkstart, blklen);
 	case BLK_ZONE_TYPE_SEQWRITE_REQ:
 	case BLK_ZONE_TYPE_SEQWRITE_PREF:
 		sector = SECTOR_FROM_BLOCK(blkstart);
@@ -848,7 +853,7 @@ static int __issue_discard_async(struct f2fs_sb_info *sbi,
 				bdev_zoned_model(bdev) != BLK_ZONED_NONE)
 		return __f2fs_issue_discard_zone(sbi, bdev, blkstart, blklen);
 #endif
-	return __f2fs_issue_discard_async(sbi, bdev, blkstart, blklen);
+	return __queue_discard_cmd(sbi, bdev, blkstart, blklen);
 }
 
 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
-- 
2.11.0