Re: [PATCH 1/7] xfs: create a big array data structure

["Darrick J. Wong" <djwong@kernel.org>]

On Thu, Jun 22, 2023 at 12:55:43PM +1000, Dave Chinner wrote:
> On Thu, May 25, 2023 at 05:47:08PM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@kernel.org>
> > 
> > Create a simple 'big array' data structure for storage of fixed-size
> > metadata records that will be used to reconstruct a btree index.  For
> > repair operations, the most important operations are append, iterate,
> > and sort.
> ....
> > +/*
> > + * Initialize a big memory array.  Array records cannot be larger than a
> > + * page, and the array cannot span more bytes than the page cache supports.
> > + * If @required_capacity is nonzero, the maximum array size will be set to this
> > + * quantity and the array creation will fail if the underlying storage cannot
> > + * support that many records.
> > + */
> > +int
> > +xfarray_create(
> > +	struct xfs_mount	*mp,
> > +	const char		*description,
> > +	unsigned long long	required_capacity,
> > +	size_t			obj_size,
> > +	struct xfarray		**arrayp)
> > +{
> > +	struct xfarray		*array;
> > +	struct xfile		*xfile;
> > +	int			error;
> > +
> > +	ASSERT(obj_size < PAGE_SIZE);
> > +
> > +	error = xfile_create(mp, description, 0, &xfile);
> > +	if (error)
> > +		return error;
> 
> The xfarray and xfile can be completely independent of anything XFS
> at all by passing the full xfile "filename" that is to be used here
> rather than having xfile_create prefix the description with a string
> like "XFS (devname):".

Ok, I'll shift the "XFS (devname)" part into the callers for the next
round.

--D

> .....
> 
> Otherwise this is all fine.
> 
> -Dave.
> -- 
> Dave Chinner
> david@fromorbit.com