Commit 944d3f9f authored by Nikolay Borisov's avatar Nikolay Borisov Committed by David Sterba
Browse files

btrfs: switch seed device to list api 



While this patch touches a bunch of files the conversion is
straighforward. Instead of using the implicit linked list anchored at
btrfs_fs_devices::seed the code is switched to using
list_for_each_entry.

Previous patches in the series already factored out code that processed
both main and seed devices so in those cases the factored out functions
are called on the main fs_devices and then on every seed dev inside
list_for_each_entry.

Using list api also allows to simplify deletion from the seed dev list
performed in btrfs_rm_device and btrfs_rm_dev_replace_free_srcdev by
substituting a while() loop with a simple list_del_init.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Reviewed-by: default avatarAnand Jain <anand.jain@oracle.com>
Signed-off-by: default avatarNikolay Borisov <nborisov@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent c4989c2f

fs/btrfs/disk-io.c

+18 −21
Original line number Diff line number Diff line
@@ -545,33 +545,30 @@ static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page) 
static int check_tree_block_fsid(struct extent_buffer *eb)

{

	struct btrfs_fs_info *fs_info = eb->fs_info;

	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;

	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;

	u8 fsid[BTRFS_FSID_SIZE];

	int ret = 1;

	u8 *metadata_uuid;



	read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),

			   BTRFS_FSID_SIZE);

	while (fs_devices) {

		u8 *metadata_uuid;



	/*

		 * Checking the incompat flag is only valid for the current

		 * fs. For seed devices it's forbidden to have their uuid

		 * changed so reading ->fsid in this case is fine

	 * Checking the incompat flag is only valid for the current fs. For

	 * seed devices it's forbidden to have their uuid changed so reading

	 * ->fsid in this case is fine

	 */

		if (fs_devices == fs_info->fs_devices &&

		    btrfs_fs_incompat(fs_info, METADATA_UUID))

	if (btrfs_fs_incompat(fs_info, METADATA_UUID))

		metadata_uuid = fs_devices->metadata_uuid;

	else

		metadata_uuid = fs_devices->fsid;



		if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE)) {

			ret = 0;

			break;

		}

		fs_devices = fs_devices->seed;

	}

	return ret;

	if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))

		return 0;



	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)

		if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))

			return 0;



	return 1;

}



static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,

fs/btrfs/reada.c

+3 −6
Original line number Diff line number Diff line
@@ -791,16 +791,13 @@ static int reada_start_for_fsdevs(struct btrfs_fs_devices *fs_devices) 


static void __reada_start_machine(struct btrfs_fs_info *fs_info)

{

	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;

	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;

	int i;

	u64 enqueued = 0;



again:

	enqueued += reada_start_for_fsdevs(fs_devices);

	if (fs_devices->seed) {

		fs_devices = fs_devices->seed;

		goto again;

	}

	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)

		enqueued += reada_start_for_fsdevs(seed_devs);



	if (enqueued == 0)

		return;

fs/btrfs/volumes.c

+48 −55
Original line number Diff line number Diff line
@@ -356,6 +356,7 @@ static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid, 
	INIT_LIST_HEAD(&fs_devs->devices);

	INIT_LIST_HEAD(&fs_devs->alloc_list);

	INIT_LIST_HEAD(&fs_devs->fs_list);

	INIT_LIST_HEAD(&fs_devs->seed_list);

	if (fsid)

		memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
@@ -1097,14 +1098,13 @@ static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, 
void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step)

{

	struct btrfs_device *latest_dev = NULL;

	struct btrfs_fs_devices *seed_dev;



	mutex_lock(&uuid_mutex);

again:

	__btrfs_free_extra_devids(fs_devices, step, &latest_dev);

	if (fs_devices->seed) {

		fs_devices = fs_devices->seed;

		goto again;

	}



	list_for_each_entry(seed_dev, &fs_devices->seed_list, seed_list)

		__btrfs_free_extra_devids(seed_dev, step, &latest_dev);



	fs_devices->latest_bdev = latest_dev->bdev;
@@ -1178,20 +1178,18 @@ static void close_fs_devices(struct btrfs_fs_devices *fs_devices) 


void btrfs_close_devices(struct btrfs_fs_devices *fs_devices)

{

	struct btrfs_fs_devices *seed_devices = NULL;

	LIST_HEAD(list);

	struct btrfs_fs_devices *tmp;



	mutex_lock(&uuid_mutex);

	close_fs_devices(fs_devices);

	if (!fs_devices->opened) {

		seed_devices = fs_devices->seed;

		fs_devices->seed = NULL;

	}

	if (!fs_devices->opened)

		list_splice_init(&fs_devices->seed_list, &list);

	mutex_unlock(&uuid_mutex);



	while (seed_devices) {

		fs_devices = seed_devices;

		seed_devices = fs_devices->seed;

	list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) {

		close_fs_devices(fs_devices);

		list_del(&fs_devices->seed_list);

		free_fs_devices(fs_devices);

	}

}
@@ -2169,14 +2167,7 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, 
	btrfs_free_device(device);



	if (cur_devices->open_devices == 0) {

		while (fs_devices) {

			if (fs_devices->seed == cur_devices) {

				fs_devices->seed = cur_devices->seed;

				break;

			}

			fs_devices = fs_devices->seed;

		}

		cur_devices->seed = NULL;

		list_del_init(&cur_devices->seed_list);

		close_fs_devices(cur_devices);

		free_fs_devices(cur_devices);

	}
@@ -2236,8 +2227,6 @@ void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev) 


	/* if this is no devs we rather delete the fs_devices */

	if (!fs_devices->num_devices) {

		struct btrfs_fs_devices *tmp_fs_devices;



		/*

		 * On a mounted FS, num_devices can't be zero unless it's a

		 * seed. In case of a seed device being replaced, the replace
@@ -2246,15 +2235,7 @@ void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev) 
		 */

		ASSERT(fs_devices->seeding);



		tmp_fs_devices = fs_info->fs_devices;

		while (tmp_fs_devices) {

			if (tmp_fs_devices->seed == fs_devices) {

				tmp_fs_devices->seed = fs_devices->seed;

				break;

			}

			tmp_fs_devices = tmp_fs_devices->seed;

		}

		fs_devices->seed = NULL;

		list_del_init(&fs_devices->seed_list);

		close_fs_devices(fs_devices);

		free_fs_devices(fs_devices);

	}
@@ -2409,7 +2390,7 @@ static int btrfs_prepare_sprout(struct btrfs_fs_info *fs_info) 
	fs_devices->open_devices = 0;

	fs_devices->missing_devices = 0;

	fs_devices->rotating = false;

	fs_devices->seed = seed_devices;

	list_add(&seed_devices->seed_list, &fs_devices->seed_list);



	generate_random_uuid(fs_devices->fsid);

	memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE);
@@ -6465,11 +6446,21 @@ struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices, 
				       bool seed)

{

	struct btrfs_device *device;

	struct btrfs_fs_devices *seed_devs;



	if (!fsid || !memcmp(fs_devices->metadata_uuid, fsid, BTRFS_FSID_SIZE)) {

		list_for_each_entry(device, &fs_devices->devices, dev_list) {

			if (device->devid == devid &&

			    (!uuid || memcmp(device->uuid, uuid,

					     BTRFS_UUID_SIZE) == 0))

				return device;

		}

	}



	while (fs_devices) {

	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {

		if (!fsid ||

		    !memcmp(fs_devices->metadata_uuid, fsid, BTRFS_FSID_SIZE)) {

			list_for_each_entry(device, &fs_devices->devices,

		    !memcmp(seed_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE)) {

			list_for_each_entry(device, &seed_devs->devices,

					    dev_list) {

				if (device->devid == devid &&

				    (!uuid || memcmp(device->uuid, uuid,
@@ -6477,11 +6468,8 @@ struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices, 
					return device;

			}

		}

		if (seed)

			fs_devices = fs_devices->seed;

		else

			return NULL;

	}



	return NULL;

}
@@ -6732,13 +6720,10 @@ static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info, 
	lockdep_assert_held(&uuid_mutex);

	ASSERT(fsid);



	fs_devices = fs_info->fs_devices->seed;

	while (fs_devices) {

	list_for_each_entry(fs_devices, &fs_info->fs_devices->seed_list, seed_list)

		if (!memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE))

			return fs_devices;



		fs_devices = fs_devices->seed;

	}



	fs_devices = find_fsid(fsid, NULL);

	if (!fs_devices) {
@@ -6772,8 +6757,7 @@ static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info, 
		goto out;

	}



	fs_devices->seed = fs_info->fs_devices->seed;

	fs_info->fs_devices->seed = fs_devices;

	list_add(&fs_devices->seed_list, &fs_info->fs_devices->seed_list);

out:

	return fs_devices;

}
@@ -7193,17 +7177,23 @@ error: 


void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)

{

	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;

	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;

	struct btrfs_device *device;



	while (fs_devices) {

	fs_devices->fs_info = fs_info;



	mutex_lock(&fs_devices->device_list_mutex);

	list_for_each_entry(device, &fs_devices->devices, dev_list)

		device->fs_info = fs_info;

	mutex_unlock(&fs_devices->device_list_mutex);



		fs_devices->fs_info = fs_info;

		fs_devices = fs_devices->seed;

	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {

		mutex_lock(&seed_devs->device_list_mutex);

		list_for_each_entry(device, &seed_devs->devices, dev_list)

			device->fs_info = fs_info;

		mutex_unlock(&seed_devs->device_list_mutex);



		seed_devs->fs_info = fs_info;

	}

}
@@ -7581,8 +7571,11 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info, 


	/* It's possible this device is a dummy for seed device */

	if (dev->disk_total_bytes == 0) {

		dev = btrfs_find_device(fs_info->fs_devices->seed, devid, NULL,

					NULL, false);

		struct btrfs_fs_devices *devs;



		devs = list_first_entry(&fs_info->fs_devices->seed_list,

					struct btrfs_fs_devices, seed_list);

		dev = btrfs_find_device(devs, devid, NULL, NULL, false);

		if (!dev) {

			btrfs_err(fs_info, "failed to find seed devid %llu",

				  devid);

fs/btrfs/volumes.h

+1 −1
Original line number Diff line number Diff line
@@ -246,7 +246,7 @@ struct btrfs_fs_devices { 
	 */

	struct list_head alloc_list;



	struct btrfs_fs_devices *seed;

	struct list_head seed_list;

	bool seeding;



	int opened;

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