| Message ID | 20161123042222.GA30324@birch.djwong.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Nov 22, 2016 at 08:22:22PM -0800, Darrick J. Wong wrote: > Fix the discussion of the limitations on the dest_count and src_length > parameters to the fideduperange ioctl to reflect what's actually in the > kernel. > > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> > --- > man2/ioctl_fideduperange.2 | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/man2/ioctl_fideduperange.2 b/man2/ioctl_fideduperange.2 > index 2112d10..59f0ea9 100644 > --- a/man2/ioctl_fideduperange.2 > +++ b/man2/ioctl_fideduperange.2 > @@ -95,7 +95,7 @@ struct file_dedupe_range_info { > .in > > Each deduplication operation targets > -.IR length > +.IR src_length > bytes in file descriptor > .IR dest_fd > at offset > @@ -108,8 +108,14 @@ During the call, > must be open for reading and > .IR dest_fd > must be open for writing. > -For any call to this ioctl, there may not be more than 65,536 > -requests attached; each request may not exceed 16MiB. > +The combined size of the struct > +.IR file_dedupe_range > +and the struct > +.IR file_dedupe_range_info > +array must not exceed the system page size. > +The maximum size of > +.IR src_length > +is filesystem dependent and is typically 16MiB. > By convention, the storage used by > .IR src_fd > is mapped into Might be worth it to clarify that the file_dedupe_range_info limit is a hard limit that will result in an error if exceeded and that the src_length limit is silently enforced. These semantics suck...
On Tue, Nov 22, 2016 at 08:39:18PM -0800, Omar Sandoval wrote: > On Tue, Nov 22, 2016 at 08:22:22PM -0800, Darrick J. Wong wrote: > > Fix the discussion of the limitations on the dest_count and src_length > > parameters to the fideduperange ioctl to reflect what's actually in the > > kernel. > > > > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> > > --- > > man2/ioctl_fideduperange.2 | 12 +++++++++--- > > 1 file changed, 9 insertions(+), 3 deletions(-) > > > > diff --git a/man2/ioctl_fideduperange.2 b/man2/ioctl_fideduperange.2 > > index 2112d10..59f0ea9 100644 > > --- a/man2/ioctl_fideduperange.2 > > +++ b/man2/ioctl_fideduperange.2 > > @@ -95,7 +95,7 @@ struct file_dedupe_range_info { > > .in > > > > Each deduplication operation targets > > -.IR length > > +.IR src_length > > bytes in file descriptor > > .IR dest_fd > > at offset > > @@ -108,8 +108,14 @@ During the call, > > must be open for reading and > > .IR dest_fd > > must be open for writing. > > -For any call to this ioctl, there may not be more than 65,536 > > -requests attached; each request may not exceed 16MiB. > > +The combined size of the struct > > +.IR file_dedupe_range > > +and the struct > > +.IR file_dedupe_range_info > > +array must not exceed the system page size. > > +The maximum size of > > +.IR src_length > > +is filesystem dependent and is typically 16MiB. > > By convention, the storage used by > > .IR src_fd > > is mapped into > > Might be worth it to clarify that the file_dedupe_range_info limit is a > hard limit that will result in an error if exceeded and that the > src_length limit is silently enforced. These semantics suck... Yeah... :( Anyway I'll post a v2 patch. --D > > -- > Omar > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/man2/ioctl_fideduperange.2 b/man2/ioctl_fideduperange.2 index 2112d10..59f0ea9 100644 --- a/man2/ioctl_fideduperange.2 +++ b/man2/ioctl_fideduperange.2 @@ -95,7 +95,7 @@ struct file_dedupe_range_info { .in Each deduplication operation targets -.IR length +.IR src_length bytes in file descriptor .IR dest_fd at offset @@ -108,8 +108,14 @@ During the call, must be open for reading and .IR dest_fd must be open for writing. -For any call to this ioctl, there may not be more than 65,536 -requests attached; each request may not exceed 16MiB. +The combined size of the struct +.IR file_dedupe_range +and the struct +.IR file_dedupe_range_info +array must not exceed the system page size. +The maximum size of +.IR src_length +is filesystem dependent and is typically 16MiB. By convention, the storage used by .IR src_fd is mapped into
Fix the discussion of the limitations on the dest_count and src_length parameters to the fideduperange ioctl to reflect what's actually in the kernel. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> --- man2/ioctl_fideduperange.2 | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html