Re: [RFC/PATCH 3/7] Powerpc MSI ops layer

[Jake Moilanen <moilanen@austin.ibm.com>]

On Tue, 2006-10-24 at 11:51 +1000, Michael Ellerman wrote:
> On Tue, 2006-10-03 at 16:54 -0500, Jake Moilanen wrote:
> > On Fri, 2006-09-29 at 07:53 +1000, Michael Ellerman wrote:
> > > Powerpc MSI ops layer.
> > > 
> > > Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
> > > ---
> > > 
> > >  arch/powerpc/kernel/msi.c        |  347 +++++++++++++++++++++++++++++++++++++++
> > >  include/asm-powerpc/machdep.h    |    6 
> > >  include/asm-powerpc/msi.h        |  175 +++++++++++++++++++
> > >  include/asm-powerpc/pci-bridge.h |    4 
> > >  4 files changed, 532 insertions(+)
> > > 
> > > Index: to-merge/arch/powerpc/kernel/msi.c
> > > ===================================================================
> > > --- /dev/null
> > > +++ to-merge/arch/powerpc/kernel/msi.c
> > > @@ -0,0 +1,347 @@
> > > +/*
> > > + * Copyright 2006 (C), Michael Ellerman, IBM Corporation.
> > > + *
> > > + * This program is free software; you can redistribute it and/or
> > > + * modify it under the terms of the GNU General Public License
> > > + * as published by the Free Software Foundation; either version
> > > + * 2 of the License, or (at your option) any later version.
> > > + */
> > > +
> > > +#undef DEBUG
> > > +
> > > +#include <linux/kernel.h>
> > > +#include <linux/slab.h>
> > > +#include <asm/msi.h>
> > > +#include <asm/machdep.h>
> > > +
> > > +static struct ppc_msi_ops *get_msi_ops(struct pci_dev *pdev)
> > > +{
> > > +	if (ppc_md.get_msi_ops)
> > > +		return ppc_md.get_msi_ops(pdev);
> > > +	return NULL;
> > > +}
> > > +
> > > +/* Activated by pci=nomsi on the command line. */
> > > +static int no_msi;
> > > +
> > > +void pci_no_msi(void)
> > > +{
> > > +	no_msi = 1;
> > > +}
> > > +
> > > +
> > > +/* msi_info helpers */
> > > +
> > > +static struct pci_dn *get_pdn(struct pci_dev *pdev)
> > > +{
> > > +	struct device_node *dn;
> > > +	struct pci_dn *pdn;
> > > +
> > > +	dn = pci_device_to_OF_node(pdev);
> > > +	if (!dn) {
> > > +		pr_debug("get_pdn: no dn found for %s\n", pci_name(pdev));
> > > +		return NULL;
> > > +	}
> > > +
> > > +	pdn = PCI_DN(dn);
> > > +	if (!pdn) {
> > > +		pr_debug("get_pdn: no pci_dn found for %s\n", pci_name(pdev));
> > > +		return NULL;
> > > +	}
> > > +
> > > +	return pdn;
> > > +}
> > > +
> > > +static int alloc_msi_info(struct pci_dev *pdev, int num,
> > > +			struct msix_entry *entries, int type)
> > > +{
> > > +	struct msi_info *info;
> > > +	unsigned int entries_size;
> > > +	struct pci_dn *pdn;
> > > +
> > > +	entries_size = sizeof(struct msix_entry) * num;
> > > +
> > > +	info = kzalloc(sizeof(struct msi_info) + entries_size, GFP_KERNEL);
> > 
> > Shouldn't you do a second kzalloc for info->entries, and not just add on
> > the size to the end?
> 
> We could, but I don't see why it's better. It's a little sneaky to tack
> the entries on the end but I don't see a problem with it?
> 
> There is a bug in there that I don't set the entries pointer before
> doing the memcpy, but I've fixed that - or is that what you meant ? :)

Yeah...I was just pointing out there was a bug.  :)