diff options
| -rw-r--r-- | fs/btrfs/send.c | 50 | ||||
| -rw-r--r-- | fs/btrfs/send.h | 1 | ||||
| -rw-r--r-- | include/uapi/linux/btrfs.h | 7 |
3 files changed, 54 insertions, 4 deletions
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 614da0d44d56..68da757615ae 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -85,6 +85,7 @@ struct send_ctx { u32 send_max_size; u64 total_send_size; u64 cmd_send_size[BTRFS_SEND_C_MAX + 1]; + u64 flags; /* 'flags' member of btrfs_ioctl_send_args is u64 */ struct vfsmount *mnt; @@ -3709,6 +3710,39 @@ out: return ret; } +/* + * Send an update extent command to user space. + */ +static int send_update_extent(struct send_ctx *sctx, + u64 offset, u32 len) +{ + int ret = 0; + struct fs_path *p; + + p = fs_path_alloc(sctx); + if (!p) + return -ENOMEM; + + ret = begin_cmd(sctx, BTRFS_SEND_C_UPDATE_EXTENT); + if (ret < 0) + goto out; + + ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p); + if (ret < 0) + goto out; + + TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p); + TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset); + TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, len); + + ret = send_cmd(sctx); + +tlv_put_failure: +out: + fs_path_free(sctx, p); + return ret; +} + static int send_write_or_clone(struct send_ctx *sctx, struct btrfs_path *path, struct btrfs_key *key, @@ -3744,7 +3778,11 @@ static int send_write_or_clone(struct send_ctx *sctx, goto out; } - if (!clone_root) { + if (clone_root) { + ret = send_clone(sctx, offset, len, clone_root); + } else if (sctx->flags & BTRFS_SEND_FLAG_NO_FILE_DATA) { + ret = send_update_extent(sctx, offset, len); + } else { while (pos < len) { l = len - pos; if (l > BTRFS_SEND_READ_SIZE) @@ -3757,10 +3795,7 @@ static int send_write_or_clone(struct send_ctx *sctx, pos += ret; } ret = 0; - } else { - ret = send_clone(sctx, offset, len, clone_root); } - out: return ret; } @@ -4560,6 +4595,11 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) goto out; } + if (arg->flags & ~BTRFS_SEND_FLAG_NO_FILE_DATA) { + ret = -EINVAL; + goto out; + } + sctx = kzalloc(sizeof(struct send_ctx), GFP_NOFS); if (!sctx) { ret = -ENOMEM; @@ -4571,6 +4611,8 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) INIT_RADIX_TREE(&sctx->name_cache, GFP_NOFS); INIT_LIST_HEAD(&sctx->name_cache_list); + sctx->flags = arg->flags; + sctx->send_filp = fget(arg->send_fd); if (IS_ERR(sctx->send_filp)) { ret = PTR_ERR(sctx->send_filp); diff --git a/fs/btrfs/send.h b/fs/btrfs/send.h index 1bf4f32fd4ef..8bb18f7ccaa6 100644 --- a/fs/btrfs/send.h +++ b/fs/btrfs/send.h @@ -86,6 +86,7 @@ enum btrfs_send_cmd { BTRFS_SEND_C_UTIMES, BTRFS_SEND_C_END, + BTRFS_SEND_C_UPDATE_EXTENT, __BTRFS_SEND_C_MAX, }; #define BTRFS_SEND_C_MAX (__BTRFS_SEND_C_MAX - 1) diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index cffbb582dd90..dd9f1293ab35 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -407,6 +407,13 @@ struct btrfs_ioctl_received_subvol_args { __u64 reserved[16]; /* in */ }; +/* + * Caller doesn't want file data in the send stream, even if the + * search of clone sources doesn't find an extent. UPDATE_EXTENT + * commands will be sent instead of WRITE commands. + */ +#define BTRFS_SEND_FLAG_NO_FILE_DATA 0x1 + struct btrfs_ioctl_send_args { __s64 send_fd; /* in */ __u64 clone_sources_count; /* in */ |