Btrfs: Add support for device scanning and detection ioctls (8a4b83cc) · Commits · e / devices / android_kernel_fairphone_FP5

fs/btrfs/ctree.h

+19 −2

Original line number	Diff line number	Diff line
		@@ -37,7 +37,7 @@ extern struct kmem_cache *btrfs_transaction_cachep;
		extern struct kmem_cache *btrfs_bit_radix_cachep;
		extern struct kmem_cache *btrfs_path_cachep;

		#define BTRFS_MAGIC "_B4RfS_M"
		#define BTRFS_MAGIC "_B5RfS_M"

		#define BTRFS_MAX_LEVEL 8

		@@ -238,6 +238,7 @@ struct btrfs_super_block {
		__le64 total_bytes;
		__le64 bytes_used;
		__le64 root_dir_objectid;
		__le64 num_devices;
		__le32 sectorsize;
		__le32 nodesize;
		__le32 leafsize;
		@@ -440,6 +441,7 @@ struct btrfs_block_group_cache {
		};

		struct btrfs_device;
		struct btrfs_fs_devices;
		struct btrfs_fs_info {
		u8 fsid[BTRFS_FSID_SIZE];
		struct btrfs_root *extent_root;
		@@ -489,7 +491,7 @@ struct btrfs_fs_info {
		u64 total_pinned;
		struct list_head dirty_cowonly_roots;

		struct list_head devices;
		struct btrfs_fs_devices *fs_devices;
		struct list_head space_info;
		spinlock_t delalloc_lock;
		spinlock_t new_trans_lock;
		@@ -677,6 +679,19 @@ BTRFS_SETGET_FUNCS(device_io_width, struct btrfs_dev_item, io_width, 32);
		BTRFS_SETGET_FUNCS(device_sector_size, struct btrfs_dev_item, sector_size, 32);
		BTRFS_SETGET_FUNCS(device_id, struct btrfs_dev_item, devid, 64);

		BTRFS_SETGET_STACK_FUNCS(stack_device_type, struct btrfs_dev_item, type, 64);
		BTRFS_SETGET_STACK_FUNCS(stack_device_total_bytes, struct btrfs_dev_item,
		total_bytes, 64);
		BTRFS_SETGET_STACK_FUNCS(stack_device_bytes_used, struct btrfs_dev_item,
		bytes_used, 64);
		BTRFS_SETGET_STACK_FUNCS(stack_device_io_align, struct btrfs_dev_item,
		io_align, 32);
		BTRFS_SETGET_STACK_FUNCS(stack_device_io_width, struct btrfs_dev_item,
		io_width, 32);
		BTRFS_SETGET_STACK_FUNCS(stack_device_sector_size, struct btrfs_dev_item,
		sector_size, 32);
		BTRFS_SETGET_STACK_FUNCS(stack_device_id, struct btrfs_dev_item, devid, 64);

		static inline char btrfs_device_uuid(struct btrfs_dev_item d)
		{
		return (char *)d + offsetof(struct btrfs_dev_item, uuid);
		@@ -1106,6 +1121,8 @@ BTRFS_SETGET_STACK_FUNCS(super_stripesize, struct btrfs_super_block,
		stripesize, 32);
		BTRFS_SETGET_STACK_FUNCS(super_root_dir, struct btrfs_super_block,
		root_dir_objectid, 64);
		BTRFS_SETGET_STACK_FUNCS(super_num_devices, struct btrfs_super_block,
		num_devices, 64);

		static inline unsigned long btrfs_leaf_data(struct extent_buffer *l)
		{

fs/btrfs/disk-io.c

+15 −9

Original line number	Diff line number	Diff line
		@@ -365,12 +365,12 @@ static int close_all_devices(struct btrfs_fs_info *fs_info)
		struct list_head *next;
		struct btrfs_device *device;

		list = &fs_info->devices;
		while(!list_empty(list)) {
		next = list->next;
		list_del(next);
		list = &fs_info->fs_devices->devices;
		list_for_each(next, list) {
		device = list_entry(next, struct btrfs_device, dev_list);
		kfree(device);
		if (device->bdev && device->bdev != fs_info->sb->s_bdev)
		close_bdev_excl(device->bdev);
		device->bdev = NULL;
		}
		return 0;
		}
		@@ -655,7 +655,8 @@ static int add_hasher(struct btrfs_fs_info info, char type) {
		return 0;
		}
		#endif
		struct btrfs_root open_ctree(struct super_block sb)
		struct btrfs_root open_ctree(struct super_block sb,
		struct btrfs_fs_devices *fs_devices)
		{
		u32 sectorsize;
		u32 nodesize;
		@@ -697,8 +698,8 @@ struct btrfs_root open_ctree(struct super_block sb)
		fs_info->extent_root = extent_root;
		fs_info->chunk_root = chunk_root;
		fs_info->dev_root = dev_root;
		fs_info->fs_devices = fs_devices;
		INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
		INIT_LIST_HEAD(&fs_info->devices);
		INIT_LIST_HEAD(&fs_info->space_info);
		btrfs_mapping_init(&fs_info->mapping_tree);
		fs_info->sb = sb;
		@@ -779,6 +780,12 @@ struct btrfs_root open_ctree(struct super_block sb)
		if (!btrfs_super_root(disk_super))
		goto fail_sb_buffer;

		if (btrfs_super_num_devices(disk_super) != fs_devices->num_devices) {
		printk("Btrfs: wanted %llu devices, but found %llu\n",
		(unsigned long long)btrfs_super_num_devices(disk_super),
		(unsigned long long)fs_devices->num_devices);
		goto fail_sb_buffer;
		}
		nodesize = btrfs_super_nodesize(disk_super);
		leafsize = btrfs_super_leafsize(disk_super);
		sectorsize = btrfs_super_sectorsize(disk_super);
		@@ -799,8 +806,6 @@ struct btrfs_root open_ctree(struct super_block sb)
		}

		mutex_lock(&fs_info->fs_mutex);
		ret = btrfs_read_super_device(tree_root, fs_info->sb_buffer);
		BUG_ON(ret);

		ret = btrfs_read_sys_array(tree_root);
		BUG_ON(ret);
		@@ -859,6 +864,7 @@ struct btrfs_root open_ctree(struct super_block sb)
		fail_iput:
		iput(fs_info->btree_inode);
		fail:
		close_all_devices(fs_info);
		kfree(extent_root);
		kfree(tree_root);
		kfree(fs_info);

fs/btrfs/disk-io.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -21,6 +21,7 @@

		#define BTRFS_SUPER_INFO_OFFSET (16 * 1024)
		struct btrfs_device;
		struct btrfs_fs_devices;

		struct extent_buffer read_tree_block(struct btrfs_root root, u64 bytenr,
		u32 blocksize);
		@@ -29,7 +30,8 @@ struct extent_buffer btrfs_find_create_tree_block(struct btrfs_root root,
		u64 bytenr, u32 blocksize);
		int clean_tree_block(struct btrfs_trans_handle *trans,
		struct btrfs_root root, struct extent_buffer buf);
		struct btrfs_root open_ctree(struct super_block sb);
		struct btrfs_root open_ctree(struct super_block sb,
		struct btrfs_fs_devices *fs_devices);
		int close_ctree(struct btrfs_root *root);
		int write_ctree_super(struct btrfs_trans_handle *trans,
		struct btrfs_root *root);

fs/btrfs/ioctl.h

+5 −1

Original line number	Diff line number	Diff line
		@@ -22,8 +22,10 @@

		#define BTRFS_IOCTL_MAGIC 0x94
		#define BTRFS_VOL_NAME_MAX 255
		#define BTRFS_PATH_NAME_MAX 4095

		struct btrfs_ioctl_vol_args {
		char name[BTRFS_VOL_NAME_MAX + 1];
		char name[BTRFS_PATH_NAME_MAX + 1];
		};

		#define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \
		@@ -32,4 +34,6 @@ struct btrfs_ioctl_vol_args {
		struct btrfs_ioctl_vol_args)
		#define BTRFS_IOC_RESIZE _IOW(BTRFS_IOCTL_MAGIC, 3, \
		struct btrfs_ioctl_vol_args)
		#define BTRFS_IOC_SCAN_DEV _IOW(BTRFS_IOCTL_MAGIC, 4, \
		struct btrfs_ioctl_vol_args)
		#endif

fs/btrfs/super.c

+44 −17

Original line number	Diff line number	Diff line
		@@ -44,6 +44,7 @@
		#include "ioctl.h"
		#include "print-tree.h"
		#include "xattr.h"
		#include "volumes.h"

		#define BTRFS_SUPER_MAGIC 0x9123683E

		@@ -216,7 +217,9 @@ static int parse_options (char * options,
		return 1;
		}

		static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
		static int btrfs_fill_super(struct super_block * sb,
		struct btrfs_fs_devices *fs_devices,
		void * data, int silent)
		{
		struct inode * inode;
		struct dentry * root_dentry;
		@@ -231,7 +234,7 @@ static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
		sb->s_xattr = btrfs_xattr_handlers;
		sb->s_time_gran = 1;

		tree_root = open_ctree(sb);
		tree_root = open_ctree(sb, fs_devices);

		if (!tree_root \|\| IS_ERR(tree_root)) {
		printk("btrfs: open_ctree failed\n");
		@@ -334,18 +337,23 @@ static int test_bdev_super(struct super_block s, void data)

		int btrfs_get_sb_bdev(struct file_system_type *fs_type,
		int flags, const char dev_name, void data,
		int (fill_super)(struct super_block , void *, int),
		struct vfsmount mnt, const char subvol)
		{
		struct block_device *bdev = NULL;
		struct super_block *s;
		struct dentry *root;
		struct btrfs_fs_devices *fs_devices = NULL;
		int error = 0;

		bdev = open_bdev_excl(dev_name, flags, fs_type);
		if (IS_ERR(bdev))
		return PTR_ERR(bdev);
		error = btrfs_scan_one_device(dev_name, flags, fs_type, &fs_devices);
		if (error)
		return error;

		error = btrfs_open_devices(fs_devices, flags, fs_type);
		if (error)
		return error;

		bdev = fs_devices->lowest_bdev;
		/*
		* once the super is inserted into the list by sget, s_umount
		* will protect the lockfs code from trying to start a snapshot
		@@ -372,7 +380,8 @@ int btrfs_get_sb_bdev(struct file_system_type *fs_type,
		s->s_flags = flags;
		strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
		sb_set_blocksize(s, block_size(bdev));
		error = fill_super(s, data, flags & MS_SILENT ? 1 : 0);
		error = btrfs_fill_super(s, fs_devices, data,
		flags & MS_SILENT ? 1 : 0);
		if (error) {
		up_write(&s->s_umount);
		deactivate_super(s);
		@@ -408,7 +417,7 @@ int btrfs_get_sb_bdev(struct file_system_type *fs_type,
		error_s:
		error = PTR_ERR(s);
		error_bdev:
		close_bdev_excl(bdev);
		btrfs_close_devices(fs_devices);
		error:
		return error;
		}
		@@ -421,8 +430,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type,
		char *subvol_name = NULL;

		parse_options((char *)data, NULL, &subvol_name);
		ret = btrfs_get_sb_bdev(fs_type, flags, dev_name, data,
		btrfs_fill_super, mnt,
		ret = btrfs_get_sb_bdev(fs_type, flags, dev_name, data, mnt,
		subvol_name ? subvol_name : "default");
		if (subvol_name)
		kfree(subvol_name);
		@@ -445,13 +453,6 @@ static int btrfs_statfs(struct dentry dentry, struct kstatfs buf)
		return 0;
		}

		static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
		unsigned long arg)
		{
		printk("btrfs control ioctl %d\n", cmd);
		return 0;
		}

		static struct file_system_type btrfs_fs_type = {
		.owner = THIS_MODULE,
		.name = "btrfs",
		@@ -460,6 +461,31 @@ static struct file_system_type btrfs_fs_type = {
		.fs_flags = FS_REQUIRES_DEV,
		};

		static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
		unsigned long arg)
		{
		struct btrfs_ioctl_vol_args *vol;
		struct btrfs_fs_devices *fs_devices;
		int ret;
		int len;

		vol = kmalloc(sizeof(*vol), GFP_KERNEL);
		if (copy_from_user(vol, (void __user )arg, sizeof(vol))) {
		ret = -EFAULT;
		goto out;
		}
		len = strnlen(vol->name, BTRFS_PATH_NAME_MAX);
		switch (cmd) {
		case BTRFS_IOC_SCAN_DEV:
		ret = btrfs_scan_one_device(vol->name, MS_RDONLY,
		&btrfs_fs_type, &fs_devices);
		break;
		}
		out:
		kfree(vol);
		return 0;
		}

		static void btrfs_write_super_lockfs(struct super_block *sb)
		{
		struct btrfs_root *root = btrfs_sb(sb);
		@@ -567,6 +593,7 @@ static void __exit exit_btrfs_fs(void)
		btrfs_interface_exit();
		unregister_filesystem(&btrfs_fs_type);
		btrfs_exit_sysfs();
		btrfs_cleanup_fs_uuids();
		}

		module_init(init_btrfs_fs)