x86/xen: Rework MSI teardown

X86 cannot store the irq domain pointer in struct device without breaking
XEN because the irq domain pointer takes precedence over arch_*_msi_irqs()
fallbacks.

XENs MSI teardown relies on default_teardown_msi_irqs() which invokes
arch_teardown_msi_irq(). default_teardown_msi_irqs() is a trivial iterator
over the msi entries associated to a device.

Implement this loop in xen_teardown_msi_irqs() to prepare for removal of
the fallbacks for X86.

This is a preparatory step to wrap XEN MSI alloc/free into a irq domain
which in turn allows to store the irq domain pointer in struct device and
to use the irq domain functions directly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200826112333.326841410@linutronix.de
This commit is contained in:
Thomas Gleixner 2020-08-26 13:16:55 +02:00
parent 2905c50b7d
commit 7d4d892de6

View File

@ -377,20 +377,31 @@ static void xen_initdom_restore_msi_irqs(struct pci_dev *dev)
static void xen_teardown_msi_irqs(struct pci_dev *dev)
{
struct msi_desc *msidesc;
int i;
for_each_pci_msi_entry(msidesc, dev) {
if (msidesc->irq) {
for (i = 0; i < msidesc->nvec_used; i++)
xen_destroy_irq(msidesc->irq + i);
}
}
}
static void xen_pv_teardown_msi_irqs(struct pci_dev *dev)
{
struct msi_desc *msidesc = first_pci_msi_entry(dev);
msidesc = first_pci_msi_entry(dev);
if (msidesc->msi_attrib.is_msix)
xen_pci_frontend_disable_msix(dev);
else
xen_pci_frontend_disable_msi(dev);
/* Free the IRQ's and the msidesc using the generic code. */
default_teardown_msi_irqs(dev);
xen_teardown_msi_irqs(dev);
}
static void xen_teardown_msi_irq(unsigned int irq)
{
xen_destroy_irq(irq);
WARN_ON_ONCE(1);
}
#endif
@ -413,7 +424,7 @@ int __init pci_xen_init(void)
#ifdef CONFIG_PCI_MSI
x86_msi.setup_msi_irqs = xen_setup_msi_irqs;
x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs;
x86_msi.teardown_msi_irqs = xen_pv_teardown_msi_irqs;
pci_msi_ignore_mask = 1;
#endif
return 0;
@ -437,6 +448,7 @@ static void __init xen_hvm_msi_init(void)
}
x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs;
x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
}
#endif
@ -473,6 +485,7 @@ int __init pci_xen_initial_domain(void)
#ifdef CONFIG_PCI_MSI
x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
x86_msi.teardown_msi_irqs = xen_teardown_pv_msi_irqs;
x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs;
pci_msi_ignore_mask = 1;
#endif