From f2eb0a241f0e5c135d93243b0236cb1f14c305e0 Mon Sep 17 00:00:00 2001 From: Sage Weil Date: Fri, 2 May 2008 14:43:14 -0400 Subject: [PATCH] Btrfs: Clone file data ioctl Add a new ioctl to clone file data Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 4 +- fs/btrfs/file-item.c | 12 +-- fs/btrfs/file.c | 2 +- fs/btrfs/inode.c | 171 ++++++++++++++++++++++++++++++++++++++++++- fs/btrfs/ioctl.h | 1 + 5 files changed, 179 insertions(+), 11 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 73b92dd150ff..3b6f8524a4ad 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1516,9 +1516,9 @@ int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root /* file-item.c */ int btrfs_insert_file_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, - u64 objectid, u64 pos, u64 offset, + u64 objectid, u64 pos, u64 disk_offset, u64 disk_num_bytes, - u64 num_bytes); + u64 num_bytes, u64 offset); int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 objectid, diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 9259aece6ed1..f537eb43c2c6 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -28,10 +28,10 @@ sizeof(struct btrfs_item) * 2) / \ BTRFS_CRC32_SIZE) - 1)) int btrfs_insert_file_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 objectid, u64 pos, - u64 offset, u64 disk_num_bytes, - u64 num_bytes) + struct btrfs_root *root, + u64 objectid, u64 pos, + u64 disk_offset, u64 disk_num_bytes, + u64 num_bytes, u64 offset) { int ret = 0; struct btrfs_file_extent_item *item; @@ -53,9 +53,9 @@ int btrfs_insert_file_extent(struct btrfs_trans_handle *trans, leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); - btrfs_set_file_extent_disk_bytenr(leaf, item, offset); + btrfs_set_file_extent_disk_bytenr(leaf, item, disk_offset); btrfs_set_file_extent_disk_num_bytes(leaf, item, disk_num_bytes); - btrfs_set_file_extent_offset(leaf, item, 0); + btrfs_set_file_extent_offset(leaf, item, offset); btrfs_set_file_extent_num_bytes(leaf, item, num_bytes); btrfs_set_file_extent_generation(leaf, item, trans->transid); btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG); diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 8effdf4f5d6f..a50507f3056d 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -285,7 +285,7 @@ static int noinline dirty_and_release_pages(struct btrfs_trans_handle *trans, err = btrfs_insert_file_extent(trans, root, inode->i_ino, last_pos_in_file, - 0, 0, hole_size); + 0, 0, hole_size, 0); btrfs_drop_extent_cache(inode, last_pos_in_file, last_pos_in_file + hole_size -1); btrfs_check_file(root, inode); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 994834474590..c6fae29c0b9e 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -141,7 +142,7 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end) cur_alloc_size = ins.offset; ret = btrfs_insert_file_extent(trans, root, inode->i_ino, start, ins.objectid, ins.offset, - ins.offset); + ins.offset, 0); inode->i_blocks += ins.offset >> 9; btrfs_check_file(root, inode); if (num_bytes < cur_alloc_size) { @@ -1227,7 +1228,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) err = btrfs_insert_file_extent(trans, root, inode->i_ino, hole_start, 0, 0, - hole_size); + hole_size, 0); btrfs_drop_extent_cache(inode, hole_start, (u64)-1); btrfs_check_file(root, inode); @@ -3100,6 +3101,170 @@ out: return ret; } +void dup_item_to_inode(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + struct extent_buffer *leaf, + int slot, + struct btrfs_key *key, + u64 destino) +{ + struct btrfs_path *cpath = btrfs_alloc_path(); + int len = btrfs_item_size_nr(leaf, slot); + int dstoff; + struct btrfs_key ckey = *key; + int ret; + + ckey.objectid = destino; + ret = btrfs_insert_empty_item(trans, root, cpath, &ckey, len); + dstoff = btrfs_item_ptr_offset(cpath->nodes[0], cpath->slots[0]); + copy_extent_buffer(cpath->nodes[0], leaf, dstoff, + btrfs_item_ptr_offset(leaf, slot), + len); + btrfs_release_path(root, cpath); +} + +long btrfs_ioctl_clone(struct file *file, unsigned long src_fd) +{ + struct inode *inode = fdentry(file)->d_inode; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct file *src_file; + struct inode *src; + struct btrfs_trans_handle *trans; + int ret; + u64 pos; + struct btrfs_path *path; + struct btrfs_key key; + struct extent_buffer *leaf; + u32 nritems; + int nextret; + int slot; + + src_file = fget(src_fd); + if (!src_file) + return -EBADF; + src = src_file->f_dentry->d_inode; + + ret = -EXDEV; + if (src->i_sb != inode->i_sb) + goto out_fput; + + if (inode < src) { + mutex_lock(&inode->i_mutex); + mutex_lock(&src->i_mutex); + } else { + mutex_lock(&src->i_mutex); + mutex_lock(&inode->i_mutex); + } + + ret = -ENOTEMPTY; + if (inode->i_size) + goto out_unlock; + + /* do any pending delalloc/csum calc on src, one way or + another, and lock file content */ + while (1) { + filemap_write_and_wait(src->i_mapping); + lock_extent(&BTRFS_I(src)->io_tree, 0, (u64)-1, GFP_NOFS); + if (BTRFS_I(src)->delalloc_bytes == 0) + break; + unlock_extent(&BTRFS_I(src)->io_tree, 0, (u64)-1, GFP_NOFS); + } + + mutex_lock(&root->fs_info->fs_mutex); + trans = btrfs_start_transaction(root, 0); + path = btrfs_alloc_path(); + pos = 0; + while (1) { + ret = btrfs_lookup_file_extent(trans, root, path, src->i_ino, + pos, 0); + if (ret < 0) + goto out; + if (ret > 0) { + if (path->slots[0] == 0) { + ret = 0; + goto out; + } + path->slots[0]--; + } +next_slot: + leaf = path->nodes[0]; + slot = path->slots[0]; + btrfs_item_key_to_cpu(leaf, &key, slot); + nritems = btrfs_header_nritems(leaf); + + if (btrfs_key_type(&key) > BTRFS_CSUM_ITEM_KEY || + key.objectid != src->i_ino) + goto out; + if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { + struct btrfs_file_extent_item *extent; + int found_type; + pos = key.offset; + extent = btrfs_item_ptr(leaf, slot, + struct btrfs_file_extent_item); + found_type = btrfs_file_extent_type(leaf, extent); + if (found_type == BTRFS_FILE_EXTENT_REG) { + u64 len = btrfs_file_extent_num_bytes(leaf, + extent); + u64 ds = btrfs_file_extent_disk_bytenr(leaf, + extent); + u64 dl = btrfs_file_extent_disk_num_bytes(leaf, + extent); + u64 off = btrfs_file_extent_offset(leaf, + extent); + btrfs_insert_file_extent(trans, root, + inode->i_ino, pos, + ds, dl, len, off); + /* ds == 0 means there's a hole */ + if (ds != 0) { + btrfs_inc_extent_ref(trans, root, + ds, dl, + root->root_key.objectid, + trans->transid, + inode->i_ino, pos); + } + pos = key.offset + len; + } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { + dup_item_to_inode(trans, root, path, leaf, slot, + &key, inode->i_ino); + pos = key.offset + btrfs_item_size_nr(leaf, + slot); + } + } else if (btrfs_key_type(&key) == BTRFS_CSUM_ITEM_KEY) + dup_item_to_inode(trans, root, path, leaf, slot, &key, + inode->i_ino); + + if (slot >= nritems - 1) { + nextret = btrfs_next_leaf(root, path); + if (nextret) + goto out; + } else { + path->slots[0]++; + } + goto next_slot; + } + +out: + btrfs_free_path(path); + ret = 0; + + inode->i_blocks = src->i_blocks; + i_size_write(inode, src->i_size); + btrfs_update_inode(trans, root, inode); + + unlock_extent(&BTRFS_I(src)->io_tree, 0, (u64)-1, GFP_NOFS); + + btrfs_end_transaction(trans, root); + mutex_unlock(&root->fs_info->fs_mutex); + +out_unlock: + mutex_unlock(&src->i_mutex); + mutex_unlock(&inode->i_mutex); +out_fput: + fput(src_file); + return ret; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -3116,6 +3281,8 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_ioctl_add_dev(root, (void __user *)arg); case BTRFS_IOC_BALANCE: return btrfs_balance(root->fs_info->dev_root); + case BTRFS_IOC_CLONE: + return btrfs_ioctl_clone(file, arg); } return -ENOTTY; diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index 8ad35fc4ba56..b0e73f51d636 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -36,6 +36,7 @@ struct btrfs_ioctl_vol_args { struct btrfs_ioctl_vol_args) #define BTRFS_IOC_SCAN_DEV _IOW(BTRFS_IOCTL_MAGIC, 4, \ struct btrfs_ioctl_vol_args) +#define BTRFS_IOC_CLONE _IOW(BTRFS_IOCTL_MAGIC, 9, int) #define BTRFS_IOC_ADD_DEV _IOW(BTRFS_IOCTL_MAGIC, 10, \ struct btrfs_ioctl_vol_args) #define BTRFS_IOC_RM_DEV _IOW(BTRFS_IOCTL_MAGIC, 11, \