f2fs: Cache zoned block devices zone type

With the zoned block device feature enabled, section discard
need to do a zone reset for sections contained in sequential
zones, and a regular discard (if supported) for sections
stored in conventional zones. Avoid the need for a costly
report zones to obtain a section zone type when discarding it
by caching the types of the device zones in the super block
information. This cache is initialized at mount time for mounts
with the zoned block device feature enabled.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 72 insertions, 0 deletions

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 3312284aa245..12a4f3f44a2f 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1511,6 +1511,65 @@ static int init_percpu_info(struct f2fs_sb_info *sbi)
 								GFP_KERNEL);
 }
 
+#ifdef CONFIG_BLK_DEV_ZONED
+static int init_blkz_info(struct f2fs_sb_info *sbi)
+{
+	struct block_device *bdev = sbi->sb->s_bdev;
+	sector_t nr_sectors = bdev->bd_part->nr_sects;
+	sector_t sector = 0;
+	struct blk_zone *zones;
+	unsigned int i, nr_zones;
+	unsigned int n = 0;
+	int err = -EIO;
+
+	if (!f2fs_sb_mounted_blkzoned(sbi->sb))
+		return 0;
+
+	sbi->blocks_per_blkz = SECTOR_TO_BLOCK(bdev_zone_size(bdev));
+	sbi->log_blocks_per_blkz = __ilog2_u32(sbi->blocks_per_blkz);
+	sbi->nr_blkz = SECTOR_TO_BLOCK(nr_sectors) >>
+		sbi->log_blocks_per_blkz;
+	if (nr_sectors & (bdev_zone_size(bdev) - 1))
+		sbi->nr_blkz++;
+
+	sbi->blkz_type = kmalloc(sbi->nr_blkz, GFP_KERNEL);
+	if (!sbi->blkz_type)
+		return -ENOMEM;
+
+#define F2FS_REPORT_NR_ZONES   4096
+
+	zones = kcalloc(F2FS_REPORT_NR_ZONES, sizeof(struct blk_zone),
+			GFP_KERNEL);
+	if (!zones)
+		return -ENOMEM;
+
+	/* Get block zones type */
+	while (zones && sector < nr_sectors) {
+
+		nr_zones = F2FS_REPORT_NR_ZONES;
+		err = blkdev_report_zones(bdev, sector,
+					  zones, &nr_zones,
+					  GFP_KERNEL);
+		if (err)
+			break;
+		if (!nr_zones) {
+			err = -EIO;
+			break;
+		}
+
+		for (i = 0; i < nr_zones; i++) {
+			sbi->blkz_type[n] = zones[i].type;
+			sector += zones[i].len;
+			n++;
+		}
+	}
+
+	kfree(zones);
+
+	return err;
+}
+#endif
+
 /*
  * Read f2fs raw super block.
  * Because we have two copies of super block, so read both of them
@@ -1757,6 +1816,15 @@ try_onemore:
 
 	init_ino_entry_info(sbi);
 
+#ifdef CONFIG_BLK_DEV_ZONED
+	err = init_blkz_info(sbi);
+	if (err) {
+		f2fs_msg(sb, KERN_ERR,
+			"Failed to initialize F2FS blkzone information");
+		goto free_blkz;
+	}
+#endif
+
 	/* setup f2fs internal modules */
 	err = build_segment_manager(sbi);
 	if (err) {
@@ -1935,6 +2003,10 @@ free_nm:
 	destroy_node_manager(sbi);
 free_sm:
 	destroy_segment_manager(sbi);
+#ifdef CONFIG_BLK_DEV_ZONED
+free_blkz:
+	kfree(sbi->blkz_type);
+#endif
 	kfree(sbi->ckpt);
 free_meta_inode:
 	make_bad_inode(sbi->meta_inode);