diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/send.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 145c84b44fd0..1c4b693ee4a3 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -5702,6 +5702,7 @@ static int clone_range(struct send_ctx *sctx, struct btrfs_path *dst_path, u64 ext_len; u64 clone_len; u64 clone_data_offset; + bool crossed_src_i_size = false; if (slot >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(clone_root->root, path); @@ -5759,8 +5760,10 @@ static int clone_range(struct send_ctx *sctx, struct btrfs_path *dst_path, if (key.offset >= clone_src_i_size) break; - if (key.offset + ext_len > clone_src_i_size) + if (key.offset + ext_len > clone_src_i_size) { ext_len = clone_src_i_size - key.offset; + crossed_src_i_size = true; + } clone_data_offset = btrfs_file_extent_offset(leaf, ei); if (btrfs_file_extent_disk_bytenr(leaf, ei) == disk_byte) { @@ -5821,6 +5824,25 @@ static int clone_range(struct send_ctx *sctx, struct btrfs_path *dst_path, ret = send_clone(sctx, offset, clone_len, clone_root); } + } else if (crossed_src_i_size && clone_len < len) { + /* + * If we are at i_size of the clone source inode and we + * can not clone from it, terminate the loop. This is + * to avoid sending two write operations, one with a + * length matching clone_len and the final one after + * this loop with a length of len - clone_len. + * + * When using encoded writes (BTRFS_SEND_FLAG_COMPRESSED + * was passed to the send ioctl), this helps avoid + * sending an encoded write for an offset that is not + * sector size aligned, in case the i_size of the source + * inode is not sector size aligned. That will make the + * receiver fallback to decompression of the data and + * writing it using regular buffered IO, therefore while + * not incorrect, it's not optimal due decompression and + * possible re-compression at the receiver. + */ + break; } else { ret = send_extent_data(sctx, dst_path, offset, clone_len); |