[PATCH v5] f2fs: fix zoned block device information initialization

[Wenjie Qi <qwjhust@gmail.com>]

If the max open zones of zoned devices are less than
the active logs of F2FS, the device may error due to
insufficient zone resources when multiple active logs
are being written at the same time.

Signed-off-by: Wenjie Qi <qwjhust@gmail.com>
---
 fs/f2fs/f2fs.h  |  1 +
 fs/f2fs/super.c | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 543898482f8b..161107f2d3bd 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1558,6 +1558,7 @@ struct f2fs_sb_info {
 
 #ifdef CONFIG_BLK_DEV_ZONED
 	unsigned int blocks_per_blkz;		/* F2FS blocks per zone */
+	unsigned int max_open_zones;		/* max open zone resources of the zoned device */
 #endif
 
 	/* for node-related operations */
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 1b718bebfaa1..c6709efbc294 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2388,6 +2388,16 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 	if (err)
 		goto restore_opts;
 
+#ifdef CONFIG_BLK_DEV_ZONED
+	if (sbi->max_open_zones < F2FS_OPTION(sbi).active_logs) {
+		f2fs_err(sbi,
+			"zoned: max open zones %u is too small, need at least %u open zones",
+				 sbi->max_open_zones, F2FS_OPTION(sbi).active_logs);
+		err = -EINVAL;
+		goto restore_opts;
+	}
+#endif
+
 	/* flush outstanding errors before changing fs state */
 	flush_work(&sbi->s_error_work);
 
@@ -3930,11 +3940,22 @@ static int init_blkz_info(struct f2fs_sb_info *sbi, int devi)
 	sector_t nr_sectors = bdev_nr_sectors(bdev);
 	struct f2fs_report_zones_args rep_zone_arg;
 	u64 zone_sectors;
+	unsigned int max_open_zones;
 	int ret;
 
 	if (!f2fs_sb_has_blkzoned(sbi))
 		return 0;
 
+	max_open_zones = bdev_max_open_zones(bdev);
+	if (max_open_zones && (max_open_zones < sbi->max_open_zones))
+		sbi->max_open_zones = max_open_zones;
+	if (sbi->max_open_zones < F2FS_OPTION(sbi).active_logs) {
+		f2fs_err(sbi,
+			"zoned: max open zones %u is too small, need at least %u open zones",
+				 sbi->max_open_zones, F2FS_OPTION(sbi).active_logs);
+		return -EINVAL;
+	}
+
 	zone_sectors = bdev_zone_sectors(bdev);
 	if (!is_power_of_2(zone_sectors)) {
 		f2fs_err(sbi, "F2FS does not support non power of 2 zone sizes\n");
@@ -4253,6 +4274,9 @@ static int f2fs_scan_devices(struct f2fs_sb_info *sbi)
 
 	logical_blksize = bdev_logical_block_size(sbi->sb->s_bdev);
 	sbi->aligned_blksize = true;
+#ifdef CONFIG_BLK_DEV_ZONED
+	sbi->max_open_zones = UINT_MAX;
+#endif
 
 	for (i = 0; i < max_devices; i++) {
 		if (i == 0)
-- 
2.34.1