From 543fd36d18a7cfa06ff651f18cd17deeec90cca1 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Thu, 17 Mar 2022 10:25:39 -0700 Subject: [PATCH] btrfs: send: add stream v2 definitions This adds the definitions of the new commands for send stream version 2 and their respective attributes: fallocate, FS_IOC_SETFLAGS (a.k.a. chattr), and encoded writes. It also documents two changes to the send stream format in v2: the receiver shouldn't assume a maximum command size, and the DATA attribute is encoded differently to allow for writes larger than 64k. These will be implemented in subsequent changes, and then the ioctl will accept the new version and flag. Reviewed-by: Josef Bacik Signed-off-by: Omar Sandoval Signed-off-by: David Sterba --- fs/btrfs/send.c | 2 +- fs/btrfs/send.h | 40 ++++++++++++++++++++++++++++++++++---- include/uapi/linux/btrfs.h | 7 +++++++ 3 files changed, 44 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 237753860758c..6ec31736c5228 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -7552,7 +7552,7 @@ long btrfs_ioctl_send(struct inode *inode, struct btrfs_ioctl_send_args *arg) sctx->clone_roots_cnt = arg->clone_sources_count; - sctx->send_max_size = BTRFS_SEND_BUF_SIZE; + sctx->send_max_size = BTRFS_SEND_BUF_SIZE_V1; sctx->send_buf = kvmalloc(sctx->send_max_size, GFP_KERNEL); if (!sctx->send_buf) { ret = -ENOMEM; diff --git a/fs/btrfs/send.h b/fs/btrfs/send.h index c47a2984aa5b1..858ce8132614b 100644 --- a/fs/btrfs/send.h +++ b/fs/btrfs/send.h @@ -12,7 +12,11 @@ #define BTRFS_SEND_STREAM_MAGIC "btrfs-stream" #define BTRFS_SEND_STREAM_VERSION 1 -#define BTRFS_SEND_BUF_SIZE SZ_64K +/* + * In send stream v1, no command is larger than 64K. In send stream v2, no limit + * should be assumed. + */ +#define BTRFS_SEND_BUF_SIZE_V1 SZ_64K enum btrfs_tlv_type { BTRFS_TLV_U8, @@ -80,16 +84,20 @@ enum btrfs_send_cmd { BTRFS_SEND_C_MAX_V1 = 22, /* Version 2 */ - BTRFS_SEND_C_MAX_V2 = 22, + BTRFS_SEND_C_FALLOCATE = 23, + BTRFS_SEND_C_SETFLAGS = 24, + BTRFS_SEND_C_ENCODED_WRITE = 25, + BTRFS_SEND_C_MAX_V2 = 25, /* End */ - BTRFS_SEND_C_MAX = 22, + BTRFS_SEND_C_MAX = 25, }; /* attributes in send stream */ enum { BTRFS_SEND_A_UNSPEC = 0, + /* Version 1 */ BTRFS_SEND_A_UUID = 1, BTRFS_SEND_A_CTRANSID = 2, @@ -112,6 +120,11 @@ enum { BTRFS_SEND_A_PATH_LINK = 17, BTRFS_SEND_A_FILE_OFFSET = 18, + /* + * As of send stream v2, this attribute is special: it must be the last + * attribute in a command, its header contains only the type, and its + * length is implicitly the remaining length of the command. + */ BTRFS_SEND_A_DATA = 19, BTRFS_SEND_A_CLONE_UUID = 20, @@ -120,7 +133,26 @@ enum { BTRFS_SEND_A_CLONE_OFFSET = 23, BTRFS_SEND_A_CLONE_LEN = 24, - BTRFS_SEND_A_MAX = 24, + BTRFS_SEND_A_MAX_V1 = 24, + + /* Version 2 */ + BTRFS_SEND_A_FALLOCATE_MODE = 25, + + BTRFS_SEND_A_SETFLAGS_FLAGS = 26, + + BTRFS_SEND_A_UNENCODED_FILE_LEN = 27, + BTRFS_SEND_A_UNENCODED_LEN = 28, + BTRFS_SEND_A_UNENCODED_OFFSET = 29, + /* + * COMPRESSION and ENCRYPTION default to NONE (0) if omitted from + * BTRFS_SEND_C_ENCODED_WRITE. + */ + BTRFS_SEND_A_COMPRESSION = 30, + BTRFS_SEND_A_ENCRYPTION = 31, + BTRFS_SEND_A_MAX_V2 = 31, + + /* End */ + BTRFS_SEND_A_MAX = 31, }; #ifdef __KERNEL__ diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index d956b2993970f..b6f26a434b109 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -777,6 +777,13 @@ struct btrfs_ioctl_received_subvol_args { */ #define BTRFS_SEND_FLAG_VERSION 0x8 +/* + * Send compressed data using the ENCODED_WRITE command instead of decompressing + * the data and sending it with the WRITE command. This requires protocol + * version >= 2. + */ +#define BTRFS_SEND_FLAG_COMPRESSED 0x10 + #define BTRFS_SEND_FLAG_MASK \ (BTRFS_SEND_FLAG_NO_FILE_DATA | \ BTRFS_SEND_FLAG_OMIT_STREAM_HEADER | \ -- 2.39.5