Hi Eric,
> -----Original Message-----
> From: Eric Auger [mailto:[email protected]]
> Sent: Friday, January 06, 2017 12:35 AM
> To: [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]
> Cc: [email protected]; [email protected]; linux-
> [email protected]; [email protected];
> [email protected]; [email protected]; Diana Madalina
> Craciun <[email protected]>; [email protected];
> [email protected]; Bharat Bhushan <[email protected]>;
> [email protected]
> Subject: [PATCH v6 17/18] vfio/type1: Check MSI remapping at irq domain
> level
>
> In case the IOMMU translates MSI transactions (typical case on ARM), we
> check MSI remapping capability at IRQ domain level. Otherwise it is checked
> at IOMMU level.
>
> At this stage the arm-smmu-(v3) still advertise the
> IOMMU_CAP_INTR_REMAP capability at IOMMU level. This will be removed
> in subsequent patches.
>
> Signed-off-by: Eric Auger <[email protected]>
>
> ---
>
> v6: rewrite test
> ---
> drivers/vfio/vfio_iommu_type1.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c
> b/drivers/vfio/vfio_iommu_type1.c index b473ef80..fa0b5c4 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -40,6 +40,7 @@
> #include <linux/mdev.h>
> #include <linux/notifier.h>
> #include <linux/dma-iommu.h>
> +#include <linux/irqdomain.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson
> <[email protected]>"
> @@ -1208,7 +1209,7 @@ static int vfio_iommu_type1_attach_group(void
> *iommu_data,
> struct vfio_domain *domain, *d;
> struct bus_type *bus = NULL, *mdev_bus;
> int ret;
> - bool resv_msi;
> + bool resv_msi, msi_remap;
> phys_addr_t resv_msi_base;
>
> mutex_lock(&iommu->lock);
> @@ -1284,8 +1285,10 @@ static int vfio_iommu_type1_attach_group(void
> *iommu_data,
> INIT_LIST_HEAD(&domain->group_list);
> list_add(&group->next, &domain->group_list);
>
> - if (!allow_unsafe_interrupts &&
> - !iommu_capable(bus, IOMMU_CAP_INTR_REMAP)) {
> + msi_remap = resv_msi ? irq_domain_check_msi_remap() :
There can be multiple interrupt-controller, at-least theoretically it is
possible and not sure practically it exists and supported, where not all may
support IRQ_REMAP. If that is the case be then should we check for IRQ-REMAP
for that device-bus irq-domain?
Thanks
-Bharat
> + iommu_capable(bus,
> IOMMU_CAP_INTR_REMAP);
> +
> + if (!allow_unsafe_interrupts && !msi_remap) {
> pr_warn("%s: No interrupt remapping support. Use the
> module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support
> on this platform\n",
> __func__);
> ret = -EPERM;
> --
> 1.9.1
