From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: Dave Chinner <david@fromorbit.com>
Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org,
linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org,
linux-xfs@vger.kernel.org, linux-mm@kvack.org,
linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
ocfs2-devel@oss.oracle.com
Subject: Re: [PATCH 24/25] xfs: support returning partial reflink results
Date: Fri, 12 Oct 2018 09:06:30 -0700 [thread overview]
Message-ID: <20181012160630.GE28243@magnolia> (raw)
In-Reply-To: <20181012012226.GT6311@dastard>
On Fri, Oct 12, 2018 at 12:22:26PM +1100, Dave Chinner wrote:
> On Wed, Oct 10, 2018 at 09:15:19PM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@oracle.com>
> >
> > Back when the XFS reflink code only supported clone_file_range, we were
> > only able to return zero or negative error codes to userspace. However,
> > now that copy_file_range (which returns bytes copied) can use XFS'
> > clone_file_range, we have the opportunity to return partial results.
> > For example, if userspace sends a 1GB clone request and we run out of
> > space halfway through, we at least can tell userspace that we completed
> > 512M of that request like a regular write.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> > ---
> > fs/xfs/xfs_file.c | 5 +----
> > fs/xfs/xfs_reflink.c | 19 ++++++++++++++-----
> > fs/xfs/xfs_reflink.h | 2 +-
> > 3 files changed, 16 insertions(+), 10 deletions(-)
> >
> >
> > diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> > index bc9e94bcb7a3..b2b15b8dc4a1 100644
> > --- a/fs/xfs/xfs_file.c
> > +++ b/fs/xfs/xfs_file.c
> > @@ -928,14 +928,11 @@ xfs_file_remap_range(
> > loff_t len,
> > unsigned int remap_flags)
> > {
> > - int ret;
> > -
> > if (!remap_check_flags(remap_flags, RFR_SAME_DATA))
> > return -EINVAL;
> >
> > - ret = xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out,
> > + return xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out,
> > len, remap_flags);
> > - return ret < 0 ? ret : len;
> > }
> >
> > STATIC int
> > diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
> > index e1592e751cc2..12a1fe92454e 100644
> > --- a/fs/xfs/xfs_reflink.c
> > +++ b/fs/xfs/xfs_reflink.c
> > @@ -1123,6 +1123,7 @@ xfs_reflink_remap_blocks(
> > struct xfs_inode *dest,
> > xfs_fileoff_t destoff,
> > xfs_filblks_t len,
> > + xfs_filblks_t *remapped,
> > xfs_off_t new_isize)
> > {
> > struct xfs_bmbt_irec imap;
> > @@ -1130,6 +1131,7 @@ xfs_reflink_remap_blocks(
> > int error = 0;
> > xfs_filblks_t range_len;
> >
> > + *remapped = 0;
> > /* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */
> > while (len) {
> > uint lock_mode;
> > @@ -1168,6 +1170,7 @@ xfs_reflink_remap_blocks(
> > srcoff += range_len;
> > destoff += range_len;
> > len -= range_len;
> > + *remapped += range_len;
> > }
>
> So "remapped" is a block count? Can we call this something like
> remap_len so it's obvious what it is tracking?
Ok.
> > @@ -1424,11 +1427,17 @@ xfs_reflink_remap_range(
> >
> > trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out);
> >
> > + if (len == 0) {
> > + ret = 0;
> > + goto out_unlock;
> > + }
> > +
> > dfsbno = XFS_B_TO_FSBT(mp, pos_out);
> > sfsbno = XFS_B_TO_FSBT(mp, pos_in);
> > fsblen = XFS_B_TO_FSB(mp, len);
> > ret = xfs_reflink_remap_blocks(src, sfsbno, dest, dfsbno, fsblen,
> > - pos_out + len);
> > + &remapped, pos_out + len);
> > + remapped = min_t(int64_t, len, XFS_FSB_TO_B(mp, remapped));
>
> So remapped is returned as a block count, then immediately converted
> to a byte count? Can we return it as byte count so that we don't
> have this weird unit conversion?
But then we'd have a function whose inputs are in units of blocks but
whose return value is in units of bytes.
Maybe I'll just do this to make it more explicit:
xfs_filblks_t remapped_blocks = 0;
loff_t remapped_bytes = 0;
ret = xfs_reflink_remap_blocks(..., &remapped_blocks...);
remapped_bytes = min_t(int64_t, len, XFS_FSB_TO_B(mp, remapped_blocks));
...
return remapped_bytes > 0 ? remapped_bytes : ret;
--D
> Cheers,
>
> Dave.
> --
> Dave Chinner
> david@fromorbit.com
next prev parent reply other threads:[~2018-10-12 16:06 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-11 4:12 [PATCH v3 00/25] fs: fixes for serious clone/dedupe problems Darrick J. Wong
2018-10-11 4:12 ` [PATCH 01/25] xfs: add a per-xfs trace_printk macro Darrick J. Wong
2018-10-11 13:39 ` Christoph Hellwig
2018-10-11 23:34 ` Darrick J. Wong
2018-10-11 4:12 ` [PATCH 02/25] vfs: vfs_clone_file_prep_inodes should return EINVAL for a clone from beyond EOF Darrick J. Wong
2018-10-11 13:40 ` Christoph Hellwig
2018-10-11 4:12 ` [PATCH 03/25] vfs: check file ranges before cloning files Darrick J. Wong
2018-10-11 13:42 ` Christoph Hellwig
2018-10-11 14:13 ` Amir Goldstein
2018-10-11 4:12 ` [PATCH 04/25] vfs: strengthen checking of file range inputs to generic_remap_checks Darrick J. Wong
2018-10-11 13:43 ` Christoph Hellwig
2018-10-11 4:12 ` [PATCH 05/25] vfs: avoid problematic remapping requests into partial EOF block Darrick J. Wong
2018-10-12 0:16 ` Dave Chinner
2018-10-12 16:07 ` Darrick J. Wong
2018-10-12 20:22 ` Filipe Manana
2018-10-15 0:31 ` Dave Chinner
2018-11-02 12:04 ` Filipe Manana
2018-11-02 17:42 ` Darrick J. Wong
2018-11-02 18:18 ` Filipe Manana
2018-11-02 19:05 ` Filipe Manana
2018-10-11 4:13 ` [PATCH 06/25] vfs: skip zero-length dedupe requests Darrick J. Wong
2018-10-11 4:13 ` [PATCH 07/25] vfs: combine the clone and dedupe into a single remap_file_range Darrick J. Wong
2018-10-11 4:13 ` [PATCH 08/25] vfs: rename vfs_clone_file_prep to be more descriptive Darrick J. Wong
2018-10-11 4:13 ` [PATCH 09/25] vfs: rename clone_verify_area to remap_verify_area Darrick J. Wong
2018-10-11 4:13 ` [PATCH 10/25] vfs: create generic_remap_file_range_touch to update inode metadata Darrick J. Wong
2018-10-11 4:13 ` [PATCH 11/25] vfs: pass remap flags to generic_remap_file_range_prep Darrick J. Wong
2018-10-11 4:13 ` [PATCH 12/25] vfs: pass remap flags to generic_remap_checks Darrick J. Wong
2018-10-11 4:13 ` [PATCH 13/25] vfs: make remap_file_range functions take and return bytes completed Darrick J. Wong
2018-10-11 4:14 ` [PATCH 14/25] vfs: plumb RFR_* remap flags through the vfs clone functions Darrick J. Wong
2018-10-11 4:14 ` [PATCH 15/25] vfs: plumb RFR_* remap flags through the vfs dedupe functions Darrick J. Wong
2018-10-11 4:14 ` [PATCH 16/25] vfs: make remapping to source file eof more explicit Darrick J. Wong
2018-10-11 4:14 ` [PATCH 17/25] vfs: enable remap callers that can handle short operations Darrick J. Wong
2018-10-11 5:15 ` Amir Goldstein
2018-10-11 16:04 ` Darrick J. Wong
2018-10-11 16:05 ` [PATCH v2 " Darrick J. Wong
2018-10-11 4:14 ` [PATCH 18/25] vfs: hide file range comparison function Darrick J. Wong
2018-10-11 4:14 ` [PATCH 19/25] vfs: implement opportunistic short dedupe Darrick J. Wong
2018-10-11 4:14 ` [PATCH 20/25] ocfs2: truncate page cache for clone destination file before remapping Darrick J. Wong
2018-10-11 4:14 ` [PATCH 21/25] ocfs2: fix pagecache truncation prior to reflink Darrick J. Wong
2018-10-11 4:15 ` [PATCH 22/25] ocfs2: support partial clone range and dedupe range Darrick J. Wong
2018-10-11 4:15 ` [PATCH 23/25] xfs: fix pagecache truncation prior to reflink Darrick J. Wong
2018-10-12 1:15 ` Dave Chinner
2018-10-11 4:15 ` [PATCH 24/25] xfs: support returning partial reflink results Darrick J. Wong
2018-10-12 1:22 ` Dave Chinner
2018-10-12 16:06 ` Darrick J. Wong [this message]
2018-10-11 4:15 ` [PATCH 25/25] xfs: remove redundant remap partial EOF block checks Darrick J. Wong
2018-10-12 1:22 ` Dave Chinner
2018-10-11 8:33 ` [PATCH v3 00/25] fs: fixes for serious clone/dedupe problems Amir Goldstein
2018-10-11 15:55 ` Darrick J. Wong
2018-10-13 0:05 [PATCH v4 " Darrick J. Wong
2018-10-13 0:08 ` [PATCH 24/25] xfs: support returning partial reflink results Darrick J. Wong
2018-10-14 17:35 ` Christoph Hellwig
2018-10-14 23:05 ` Dave Chinner
2018-10-15 15:49 ` Darrick J. Wong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181012160630.GE28243@magnolia \
--to=darrick.wong@oracle.com \
--cc=david@fromorbit.com \
--cc=linux-btrfs@vger.kernel.org \
--cc=linux-cifs@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-nfs@vger.kernel.org \
--cc=linux-unionfs@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=ocfs2-devel@oss.oracle.com \
--cc=sandeen@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).