[PATCH v3] f2fs: fix zoned block device information initialization

[Wenjie Qi <qwjhust@gmail.com>]

If the max active 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. If this value is 0, there is no limit.

Signed-off-by: Wenjie Qi <qwjhust@gmail.com>
---
 fs/f2fs/f2fs.h  |  1 +
 fs/f2fs/super.c | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 65294e3b0bef..669f84f6b0e5 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1551,6 +1551,7 @@ struct f2fs_sb_info {
 
 #ifdef CONFIG_BLK_DEV_ZONED
 	unsigned int blocks_per_blkz;		/* F2FS blocks per zone */
+	unsigned int max_active_zones;		/* max zone resources of the zoned device */
 #endif
 
 	/* for node-related operations */
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 206d03c82d96..aef41b54098c 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2385,6 +2385,16 @@ 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_active_zones && sbi->max_active_zones < F2FS_OPTION(sbi).active_logs) {
+		f2fs_err(sbi,
+			"zoned: max active zones %u is too small, need at least %u active zones",
+				 sbi->max_active_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);
 
@@ -3932,6 +3942,14 @@ static int init_blkz_info(struct f2fs_sb_info *sbi, int devi)
 	if (!f2fs_sb_has_blkzoned(sbi))
 		return 0;
 
+	sbi->max_active_zones = bdev_max_active_zones(bdev);
+	if (sbi->max_active_zones && sbi->max_active_zones < F2FS_OPTION(sbi).active_logs) {
+		f2fs_err(sbi,
+			"zoned: max active zones %u is too small, need at least %u active zones",
+				 sbi->max_active_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");
-- 
2.34.1