diff mbox series

[v11,14/14] btrfs: send: enable support for stream v2 and compressed writes

Message ID 61a4a5b6bf694c7441b2ba04b724d012997fa3f7.1630514529.git.osandov@fb.com (mailing list archive)
State New, archived
Headers show
Series btrfs: add ioctls and send/receive support for reading/writing compressed data | expand

Commit Message

Omar Sandoval Sept. 1, 2021, 5:01 p.m. UTC 
From: Omar Sandoval <osandov@fb.com>

Now that the new support is implemented, allow the ioctl to accept the
flags and update the version in sysfs.

Signed-off-by: Omar Sandoval <osandov@fb.com>
---
 fs/btrfs/send.c            | 10 +++++++++-
 fs/btrfs/send.h            |  2 +-
 include/uapi/linux/btrfs.h |  4 +++-
 3 files changed, 13 insertions(+), 3 deletions(-)

Comments

Nikolay Borisov Oct. 18, 2021, 12:44 p.m. UTC | #1 
On 1.09.21 г. 20:01, Omar Sandoval wrote:
> From: Omar Sandoval <osandov@fb.com>
> 
> Now that the new support is implemented, allow the ioctl to accept the
> flags and update the version in sysfs.

This seems like an appropriate place to bring up the discussion about
versioned streams. SO instead of adding a BTRFS_SEND_FLAG_STREAM_V2
flag, which implies that for the next version we have to add
BTRFS_SEND_FLAG_STREAM_V3 etc. Why not generalize the flag to
BTRFS_SEND_FLAG_STREAM_VERSIONED and carve an u32 from one of the
reserved fields so that in the future we simply increment the version field?


> 
> Signed-off-by: Omar Sandoval <osandov@fb.com>
> ---
>  fs/btrfs/send.c            | 10 +++++++++-
>  fs/btrfs/send.h            |  2 +-
>  include/uapi/linux/btrfs.h |  4 +++-
>  3 files changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
> index 0ba8dc3a9f56..90ca915fed78 100644
> --- a/fs/btrfs/send.c
> +++ b/fs/btrfs/send.c
> @@ -671,7 +671,10 @@ static int send_header(struct send_ctx *sctx)
>  	struct btrfs_stream_header hdr;
>  
>  	strcpy(hdr.magic, BTRFS_SEND_STREAM_MAGIC);
> -	hdr.version = cpu_to_le32(BTRFS_SEND_STREAM_VERSION);
> +	if (sctx->flags & BTRFS_SEND_FLAG_STREAM_V2)
> +		hdr.version = cpu_to_le32(2);
> +	else
> +		hdr.version = cpu_to_le32(1);
>  
>  	return write_buf(sctx->send_filp, &hdr, sizeof(hdr),
>  					&sctx->send_off);
> @@ -7466,6 +7469,11 @@ long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
>  		ret = -EINVAL;
>  		goto out;
>  	}
> +	if ((arg->flags & BTRFS_SEND_FLAG_COMPRESSED) &&
> +	    !(arg->flags & BTRFS_SEND_FLAG_STREAM_V2)) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
>  
>  	sctx = kzalloc(sizeof(struct send_ctx), GFP_KERNEL);
>  	if (!sctx) {
> diff --git a/fs/btrfs/send.h b/fs/btrfs/send.h
> index 9f4f7b96b1eb..9c83e14a43b2 100644
> --- a/fs/btrfs/send.h
> +++ b/fs/btrfs/send.h
> @@ -10,7 +10,7 @@
>  #include "ctree.h"
>  
>  #define BTRFS_SEND_STREAM_MAGIC "btrfs-stream"
> -#define BTRFS_SEND_STREAM_VERSION 1
> +#define BTRFS_SEND_STREAM_VERSION 2
>  
>  /*
>   * In send stream v1, no command is larger than 64k. In send stream v2, no limit
> diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
> index 4f875f355e83..5c13e407982f 100644
> --- a/include/uapi/linux/btrfs.h
> +++ b/include/uapi/linux/btrfs.h
> @@ -787,7 +787,9 @@ struct btrfs_ioctl_received_subvol_args {
>  #define BTRFS_SEND_FLAG_MASK \
>  	(BTRFS_SEND_FLAG_NO_FILE_DATA | \
>  	 BTRFS_SEND_FLAG_OMIT_STREAM_HEADER | \
> -	 BTRFS_SEND_FLAG_OMIT_END_CMD)
> +	 BTRFS_SEND_FLAG_OMIT_END_CMD | \
> +	 BTRFS_SEND_FLAG_STREAM_V2 | \
> +	 BTRFS_SEND_FLAG_COMPRESSED)
>  
>  struct btrfs_ioctl_send_args {
>  	__s64 send_fd;			/* in */
>
Omar Sandoval Oct. 18, 2021, 6:34 p.m. UTC | #2 
On Mon, Oct 18, 2021 at 03:44:23PM +0300, Nikolay Borisov wrote:
> 
> 
> On 1.09.21 г. 20:01, Omar Sandoval wrote:
> > From: Omar Sandoval <osandov@fb.com>
> > 
> > Now that the new support is implemented, allow the ioctl to accept the
> > flags and update the version in sysfs.
> 
> This seems like an appropriate place to bring up the discussion about
> versioned streams. SO instead of adding a BTRFS_SEND_FLAG_STREAM_V2
> flag, which implies that for the next version we have to add
> BTRFS_SEND_FLAG_STREAM_V3 etc. Why not generalize the flag to
> BTRFS_SEND_FLAG_STREAM_VERSIONED and carve an u32 from one of the
> reserved fields so that in the future we simply increment the version field?

Yes, that definitely sounds better.
diff mbox series

Patch

diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 0ba8dc3a9f56..90ca915fed78 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -671,7 +671,10 @@  static int send_header(struct send_ctx *sctx)
 	struct btrfs_stream_header hdr;
 
 	strcpy(hdr.magic, BTRFS_SEND_STREAM_MAGIC);
-	hdr.version = cpu_to_le32(BTRFS_SEND_STREAM_VERSION);
+	if (sctx->flags & BTRFS_SEND_FLAG_STREAM_V2)
+		hdr.version = cpu_to_le32(2);
+	else
+		hdr.version = cpu_to_le32(1);
 
 	return write_buf(sctx->send_filp, &hdr, sizeof(hdr),
 					&sctx->send_off);
@@ -7466,6 +7469,11 @@  long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
 		ret = -EINVAL;
 		goto out;
 	}
+	if ((arg->flags & BTRFS_SEND_FLAG_COMPRESSED) &&
+	    !(arg->flags & BTRFS_SEND_FLAG_STREAM_V2)) {
+		ret = -EINVAL;
+		goto out;
+	}
 
 	sctx = kzalloc(sizeof(struct send_ctx), GFP_KERNEL);
 	if (!sctx) {
diff --git a/fs/btrfs/send.h b/fs/btrfs/send.h
index 9f4f7b96b1eb..9c83e14a43b2 100644
--- a/fs/btrfs/send.h
+++ b/fs/btrfs/send.h
@@ -10,7 +10,7 @@ 
 #include "ctree.h"
 
 #define BTRFS_SEND_STREAM_MAGIC "btrfs-stream"
-#define BTRFS_SEND_STREAM_VERSION 1
+#define BTRFS_SEND_STREAM_VERSION 2
 
 /*
  * In send stream v1, no command is larger than 64k. In send stream v2, no limit
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index 4f875f355e83..5c13e407982f 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -787,7 +787,9 @@  struct btrfs_ioctl_received_subvol_args {
 #define BTRFS_SEND_FLAG_MASK \
 	(BTRFS_SEND_FLAG_NO_FILE_DATA | \
 	 BTRFS_SEND_FLAG_OMIT_STREAM_HEADER | \
-	 BTRFS_SEND_FLAG_OMIT_END_CMD)
+	 BTRFS_SEND_FLAG_OMIT_END_CMD | \
+	 BTRFS_SEND_FLAG_STREAM_V2 | \
+	 BTRFS_SEND_FLAG_COMPRESSED)
 
 struct btrfs_ioctl_send_args {
 	__s64 send_fd;			/* in */