On Mon, Jun 29, 2015 at 4:31 PM, Darrick J. Wong
<darrick.wong@xxxxxxxxxx> wrote:
>
> On Mon, Jun 29, 2015 at 02:33:56PM -0500, Steve French wrote:
> > On Mon, Jun 29, 2015 at 12:27 PM, Darrick J. Wong
> > <darrick.wong@xxxxxxxxxx> wrote:
> > >
> > > On Sun, Jun 28, 2015 at 09:21:05PM -0500, Steve French wrote:
> > > > Update the patch to correct target file size.
> > > >
> > > > Getting fantastic copy performance with cp --reflink over SMB3.11
> > > > using the new FSCTL_DUPLICATE_EXTENTS.
> > > >
> > > > This FSCTL was added in the SMB3.11 dialect (testing was
> > > > against REFS file system) so have put it as a 3.11 protocol
> > > > specific operation ("vers=3.1.1" on the mount). Tested at
> > > > the SMB3 plugfest in Redmond.
> > > >
> > > > It depends on the new FS Attribute (BLOCK_REFCOUNTING) which
> > > > is used to advertise support for the ability to do this ioctl
> > > > (if you can support multiple files pointing to the same block
> > > > than this refcounting ability or equivalent is needed to
> > > > support the new reflink-like duplicate extent SMB3 ioctl.
> > > >
> > > > Signed-off-by: Steve French <steve.french@xxxxxxxxxxxxxxx>
> > > > ---
> > > > fs/cifs/cifsglob.h | 3 +++
> > > > fs/cifs/cifspdu.h | 2 ++
> > > > fs/cifs/ioctl.c | 16 +++++++++++++---
> > > > fs/cifs/smb2ops.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
> > > > fs/cifs/smb2pdu.h | 8 ++++++++
> > > > fs/cifs/smbfsctl.h | 1 +
> > > > 6 files changed, 75 insertions(+), 3 deletions(-)
> > > >
> > > > diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> > > > index a0212ec..81194e6 100644
> > > > --- a/fs/cifs/cifsglob.h
> > > > +++ b/fs/cifs/cifsglob.h
> > > > @@ -390,6 +390,9 @@ struct smb_version_operations {
> > > > int (*clone_range)(const unsigned int, struct cifsFileInfo *src_file,
> > > > struct cifsFileInfo *target_file, u64 src_off, u64 len,
> > > > u64 dest_off);
> > > > + int (*duplicate_extents)(const unsigned int, struct cifsFileInfo *src,
> > > > + struct cifsFileInfo *target_file, u64 src_off, u64 len,
> > > > + u64 dest_off);
> > > > int (*validate_negotiate)(const unsigned int, struct cifs_tcon *);
> > > > ssize_t (*query_all_EAs)(const unsigned int, struct cifs_tcon *,
> > > > const unsigned char *, const unsigned char *, char *,
> > > > diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h
> > > > index 998a66f..47b030d 100644
> > > > --- a/fs/cifs/cifspdu.h
> > > > +++ b/fs/cifs/cifspdu.h
> > > > @@ -2255,6 +2255,8 @@ typedef struct {
> > > >
> > > >
> > > > /* List of FileSystemAttributes - see 2.5.1 of MS-FSCC */
> > > > +#define FILE_SUPPORTS_SPARSE_VDL 0x10000000 /* faster nonsparse extend */
> > > > +#define FILE_SUPPORTS_BLOCK_REFCOUNTING 0x08000000 /* allow ioctl dup extents */
> > > > #define FILE_SUPPORT_INTEGRITY_STREAMS 0x04000000
> > > > #define FILE_SUPPORTS_USN_JOURNAL 0x02000000
> > > > #define FILE_SUPPORTS_OPEN_BY_FILE_ID 0x01000000
> > > > diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
> > > > index 8b7898b..7843b19 100644
> > > > --- a/fs/cifs/ioctl.c
> > > > +++ b/fs/cifs/ioctl.c
> > > > @@ -31,12 +31,14 @@
> > > > #include "cifsproto.h"
> > > > #include "cifs_debug.h"
> > > > #include "cifsfs.h"
> > > > +#include <linux/btrfs.h>
> > > >
> > > > #define CIFS_IOCTL_MAGIC 0xCF
> > > > #define CIFS_IOC_COPYCHUNK_FILE _IOW(CIFS_IOCTL_MAGIC, 3, int)
> > > >
> > > > static long cifs_ioctl_clone(unsigned int xid, struct file *dst_file,
> > > > - unsigned long srcfd, u64 off, u64 len, u64 destoff)
> > > > + unsigned long srcfd, u64 off, u64 len, u64 destoff,
> > > > + bool dup_extents)
> > > > {
> > > > int rc;
> > > > struct cifsFileInfo *smb_file_target = dst_file->private_data;
> > > > @@ -109,9 +111,14 @@ static long cifs_ioctl_clone(unsigned int xid, struct file *dst_file,
> > > > truncate_inode_pages_range(&target_inode->i_data, destoff,
> > > > PAGE_CACHE_ALIGN(destoff + len)-1);
> > > >
> > > > - if (target_tcon->ses->server->ops->clone_range)
> > > > + if (dup_extents && target_tcon->ses->server->ops->duplicate_extents)
> > > > + rc = target_tcon->ses->server->ops->duplicate_extents(xid,
> > > > + smb_file_src, smb_file_target, off, len, destoff);
> > > > + else if (!dup_extents && target_tcon->ses->server->ops->clone_range)
> > > > rc = target_tcon->ses->server->ops->clone_range(xid,
> > > > smb_file_src, smb_file_target, off, len, destoff);
> > > > + else
> > > > + rc = -EOPNOTSUPP;
> > > >
> > > > /* force revalidate of size and timestamps of target file now
> > > > that target is updated on the server */
> > > > @@ -205,7 +212,10 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
> > > > }
> > > > break;
> > > > case CIFS_IOC_COPYCHUNK_FILE:
> > > > - rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0);
> > > > + rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0, false);
> > > > + break;
> > > > + case BTRFS_IOC_CLONE:
> > > > + rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0, true);
> > >
> > > Any interest in supporting BTRFS_IOC_CLONE_RANGE or BTRFS_IOC_EXTENT_SAME?
> > > It looks like you could easily support the former, and the latter would
> > > enable things like duperemove. I've been working on a pile of xfstests to
> > > exercise these three ioctls, will post them later today, I hope.
> > >
> > > --D
> > >
> >
> > So far Samba (server) only uses three btrfs ioctls, but that includes
> > clone range:
>
> Oh, my question was mostly about support for CLONE_RANGE within
> cifs.ko so that clients could ask for a reflink, which would then be
> sent off to the server as FSCTL_DUPLICATE_EXTENTS. That doesn't seem
> too hard, but I didn't see it in ioctl.c and wondered why. :)
>
> >
> > ./source3/modules/vfs_btrfs.c:#define BTRFS_IOC_CLONE_RANGE ...
> > ./source3/modules/vfs_btrfs.c:#define BTRFS_IOC_SNAP_DESTROY ...
> > ./source3/modules/vfs_btrfs.c:#define BTRFS_IOC_SNAP_CREATE_V2 ...
> >
> > But btrfs clone range is only (optionally if present) used to handle
> > the "CopyChunk" API (SMB3 and CIFS network protocol requests), and
> > Samba server doesn't have code for the FSCTL_DUPLICATE_EXTENTS fsctl
> > (SMB3 network protocol request) yet. It looks trivial to map that to
> > BTRFS_IOC_CLONE_RANGE in the Samba server. Would need to add trivial
> > parsing in smbd/smb2_ioctl_network_fs.c and a new VFS entry point in
> > the Samba VFS and a small helper routine in
> > source3/modules/vfs_btrfs.c
>
> Sounds fairly straightforward on the server side. I'm working on adding
> the three ioctls I mentioned (CLONE, CLONE_RANGE, EXTENT_SAME) to XFS and
> others are working on it for ext4; do you think it would be difficult to
> adapt Samba server to talk to these three btrfs APIs even with a non-btrfs
> backend?
>
> (Or, maybe someday we might refactor all this into a common syscall or
> something.)
>
> I guess BTRFS_IOC_EXTENT_SAME would be harder since you'd want to compare
> file contents on the server, and I'm not sure if SMB can actually do that.
>
cifs.ko with the recent patches, does support IOC_CLONE (ie
BTRFS_IOC_CLONE) but I didn't add BTRFS_CLONE_RANGE which would be
easy enough to add to cifs.ko (although would be a little better, and
perhaps less confusing, if there were a system ioctl definition that
was an exact equivalent of BTRFS_IOC_CLONE and BTRFS_IOC_CLONE_RANGE
but didn't use the name BTRFS, but last I checked the cp command it
only knows about BTRFS_IOC_CLONE so we are stuck using that ioctl
number).
If you call CIFS_IOC_COPYCHUNK_FILE ioctl today in cifs.ko (even
without the patches), for SMB3 mounts it will send a
FSCTL_SRV_COPYCHUNK_WRITE SMB3 request to the server which Samba will
either emulate in user space as a somewhat faster file copy, or pass
directly to btrfs if vfs_btrfs is loaded and the server will do a
BTRFS_IOC_CLONE_RANGE.
With the recent patch to cifs.ko it will be easier since for cifs
--reflink we will only issue DUPLICATE_EXTENTS IOCTL over the wire
(which Samba can convert to BRTFS_IOC_CLONE or BTRFS_IOC_CLONE_RANGE)
if the server advertises the file system support for the corresponding
attribute flag.
--
Steve French
Principal Systems Engineer: Protocols
W: 512-918-9276
C: 512-501-9669
www.primarydata.com
--
Steve French
Principal Systems Engineer: Protocols
W: 512-918-9276
C: 512-501-9669
www.primarydata.com
--
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