From 32b7c687c52a0b78a7d41ce6423c2fd8f5ca92da Mon Sep 17 00:00:00 2001 From: Mark Fasheh Date: Tue, 6 Aug 2013 11:42:49 -0700 Subject: [PATCH] btrfs_ioctl_clone: Move clone code into it's own function There's some 250+ lines here that are easily encapsulated into their own function. I don't change how anything works here, just create and document the new btrfs_clone() function from btrfs_ioctl_clone() code. Signed-off-by: Mark Fasheh Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/ioctl.c | 254 ++++++++++++++++++++++++++++++------------------------- 1 file changed, 139 insertions(+), 115 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 76c7657..5b5148a 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2490,136 +2490,43 @@ static inline void lock_extent_range(struct inode *inode, u64 off, u64 len) } } -static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, - u64 off, u64 olen, u64 destoff) +/** + * btrfs_clone() - clone a range from inode file to another + * + * @src: Inode to clone from + * @inode: Inode to clone to + * @off: Offset within source to start clone from + * @olen: Original length, passed by user, of range to clone + * @olen_aligned: Block-aligned value of olen, extent_same uses + * identical values here + * @destoff: Offset within @inode to start clone + */ +static int btrfs_clone(struct inode *src, struct inode *inode, + u64 off, u64 olen, u64 olen_aligned, u64 destoff) { - struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; - struct fd src_file; - struct inode *src; - struct btrfs_trans_handle *trans; - struct btrfs_path *path; + struct btrfs_path *path = NULL; struct extent_buffer *leaf; - char *buf; + struct btrfs_trans_handle *trans; + char *buf = NULL; struct btrfs_key key; u32 nritems; int slot; int ret; - u64 len = olen; - u64 bs = root->fs_info->sb->s_blocksize; - int same_inode = 0; - - /* - * TODO: - * - split compressed inline extents. annoying: we need to - * decompress into destination's address_space (the file offset - * may change, so source mapping won't do), then recompress (or - * otherwise reinsert) a subrange. - * - allow ranges within the same file to be cloned (provided - * they don't overlap)? - */ - - /* the destination must be opened for writing */ - if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) - return -EINVAL; - - if (btrfs_root_readonly(root)) - return -EROFS; - - ret = mnt_want_write_file(file); - if (ret) - return ret; - - src_file = fdget(srcfd); - if (!src_file.file) { - ret = -EBADF; - goto out_drop_write; - } - - ret = -EXDEV; - if (src_file.file->f_path.mnt != file->f_path.mnt) - goto out_fput; - - src = file_inode(src_file.file); - - ret = -EINVAL; - if (src == inode) - same_inode = 1; - - /* the src must be open for reading */ - if (!(src_file.file->f_mode & FMODE_READ)) - goto out_fput; - - /* don't make the dst file partly checksummed */ - if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != - (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) - goto out_fput; - - ret = -EISDIR; - if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) - goto out_fput; - - ret = -EXDEV; - if (src->i_sb != inode->i_sb) - goto out_fput; + u64 len = olen_aligned; ret = -ENOMEM; buf = vmalloc(btrfs_level_size(root, 0)); if (!buf) - goto out_fput; + return ret; path = btrfs_alloc_path(); if (!path) { vfree(buf); - goto out_fput; - } - path->reada = 2; - - if (!same_inode) { - if (inode < src) { - mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); - } else { - mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); - } - } else { - mutex_lock(&src->i_mutex); - } - - /* determine range to clone */ - ret = -EINVAL; - if (off + len > src->i_size || off + len < off) - goto out_unlock; - if (len == 0) - olen = len = src->i_size - off; - /* if we extend to eof, continue to block boundary */ - if (off + len == src->i_size) - len = ALIGN(src->i_size, bs) - off; - - /* verify the end result is block aligned */ - if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || - !IS_ALIGNED(destoff, bs)) - goto out_unlock; - - /* verify if ranges are overlapped within the same file */ - if (same_inode) { - if (destoff + len > off && destoff < off + len) - goto out_unlock; - } - - if (destoff > inode->i_size) { - ret = btrfs_cont_expand(inode, inode->i_size, destoff); - if (ret) - goto out_unlock; + return ret; } - /* truncate page cache pages from target inode range */ - truncate_inode_pages_range(&inode->i_data, destoff, - PAGE_CACHE_ALIGN(destoff + len) - 1); - - lock_extent_range(src, off, len); - + path->reada = 2; /* clone data */ key.objectid = btrfs_ino(src); key.type = BTRFS_EXTENT_DATA_KEY; @@ -2865,15 +2772,132 @@ next: key.offset++; } ret = 0; + out: btrfs_release_path(path); + btrfs_free_path(path); + vfree(buf); + return ret; +} + +static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, + u64 off, u64 olen, u64 destoff) +{ + struct inode *inode = fdentry(file)->d_inode; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct fd src_file; + struct inode *src; + int ret; + u64 len = olen; + u64 bs = root->fs_info->sb->s_blocksize; + int same_inode = 0; + + /* + * TODO: + * - split compressed inline extents. annoying: we need to + * decompress into destination's address_space (the file offset + * may change, so source mapping won't do), then recompress (or + * otherwise reinsert) a subrange. + * - allow ranges within the same file to be cloned (provided + * they don't overlap)? + */ + + /* the destination must be opened for writing */ + if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) + return -EINVAL; + + if (btrfs_root_readonly(root)) + return -EROFS; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + src_file = fdget(srcfd); + if (!src_file.file) { + ret = -EBADF; + goto out_drop_write; + } + + ret = -EXDEV; + if (src_file.file->f_path.mnt != file->f_path.mnt) + goto out_fput; + + src = file_inode(src_file.file); + + ret = -EINVAL; + if (src == inode) + same_inode = 1; + + /* the src must be open for reading */ + if (!(src_file.file->f_mode & FMODE_READ)) + goto out_fput; + + /* don't make the dst file partly checksummed */ + if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != + (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) + goto out_fput; + + ret = -EISDIR; + if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) + goto out_fput; + + ret = -EXDEV; + if (src->i_sb != inode->i_sb) + goto out_fput; + + if (!same_inode) { + if (inode < src) { + mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); + } else { + mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); + } + } else { + mutex_lock(&src->i_mutex); + } + + /* determine range to clone */ + ret = -EINVAL; + if (off + len > src->i_size || off + len < off) + goto out_unlock; + if (len == 0) + olen = len = src->i_size - off; + /* if we extend to eof, continue to block boundary */ + if (off + len == src->i_size) + len = ALIGN(src->i_size, bs) - off; + + /* verify the end result is block aligned */ + if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || + !IS_ALIGNED(destoff, bs)) + goto out_unlock; + + /* verify if ranges are overlapped within the same file */ + if (same_inode) { + if (destoff + len > off && destoff < off + len) + goto out_unlock; + } + + if (destoff > inode->i_size) { + ret = btrfs_cont_expand(inode, inode->i_size, destoff); + if (ret) + goto out_unlock; + } + + /* truncate page cache pages from target inode range */ + truncate_inode_pages_range(&inode->i_data, destoff, + PAGE_CACHE_ALIGN(destoff + len) - 1); + + lock_extent_range(src, off, len); + + ret = btrfs_clone(src, inode, off, olen, len, destoff); + unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); out_unlock: mutex_unlock(&src->i_mutex); if (!same_inode) mutex_unlock(&inode->i_mutex); - vfree(buf); - btrfs_free_path(path); out_fput: fdput(src_file); out_drop_write: -- 2.7.4