From 7365104236ade0bf22edd7724c8fd438b0342ee4 Mon Sep 17 00:00:00 2001 From: Naohiro Aota Date: Thu, 4 Feb 2021 19:21:42 +0900 Subject: btrfs: zoned: defer loading zone info after opening trees This is a preparation patch to implement zone emulation on a regular device. To emulate a zoned filesystem on a regular (non-zoned) device, we need to decide an emulated zone size. Instead of making it a compile-time static value, we'll make it configurable at mkfs time. Since we have one zone == one device extent restriction, we can determine the emulated zone size from the size of a device extent. We can extend btrfs_get_dev_zone_info() to show a regular device filled with conventional zones once the zone size is decided. The current call site of btrfs_get_dev_zone_info() during the mount process is earlier than loading the file system trees so that we don't know the size of a device extent at this point. Thus we can't slice a regular device to conventional zones. This patch introduces btrfs_get_dev_zone_info_all_devices to load the zone info for all the devices. And, it places this function in open_ctree() after loading the trees. Reviewed-by: Anand Jain Reviewed-by: Josef Bacik Signed-off-by: Naohiro Aota Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/zoned.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'fs/btrfs/zoned.c') diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c index 41d27fefd306..0b1b1f38a196 100644 --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -143,6 +143,31 @@ static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos, return 0; } +int btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info *fs_info) +{ + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + struct btrfs_device *device; + int ret = 0; + + /* fs_info->zone_size might not set yet. Use the incomapt flag here. */ + if (!btrfs_fs_incompat(fs_info, ZONED)) + return 0; + + mutex_lock(&fs_devices->device_list_mutex); + list_for_each_entry(device, &fs_devices->devices, dev_list) { + /* We can skip reading of zone info for missing devices */ + if (!device->bdev) + continue; + + ret = btrfs_get_dev_zone_info(device); + if (ret) + break; + } + mutex_unlock(&fs_devices->device_list_mutex); + + return ret; +} + int btrfs_get_dev_zone_info(struct btrfs_device *device) { struct btrfs_zoned_device_info *zone_info = NULL; -- cgit v1.2.3