Make the variable a tristate, with (as done elsewhere) a negative value
meaning "default". Since all use sites need looking at, also rename it
to match our usual "opt_*" pattern. While touching it, also move it to
.data.ro_after_init.
The only place it retains boolean nature is pci_ats_device(), for now.
In AMD code re-order conditionals to have the config space accesses
after (cheaper) flag checks.
Signed-off-by: Jan Beulich <jbeul...@suse.com>
---
In domain_context_mapping_one() I'm a little puzzled that translation
type is selected based on only IOMMU and global properties, i.e. not
taking the device itself into account.
--- a/xen/drivers/passthrough/amd/iommu_cmd.c
+++ b/xen/drivers/passthrough/amd/iommu_cmd.c
@@ -282,7 +282,7 @@ void amd_iommu_flush_iotlb(u8 devfn, con
struct amd_iommu *iommu;
unsigned int req_id, queueid, maxpend;
- if ( !ats_enabled )
+ if ( opt_ats <= 0 )
return;
if ( !pci_ats_enabled(pdev->seg, pdev->bus, pdev->devfn) )
@@ -340,7 +340,7 @@ static void _amd_iommu_flush_pages(struc
flush_command_buffer(iommu, 0);
}
- if ( ats_enabled )
+ if ( opt_ats > 0 )
{
amd_iommu_flush_all_iotlbs(d, daddr, order);
--- a/xen/drivers/passthrough/amd/pci_amd_iommu.c
+++ b/xen/drivers/passthrough/amd/pci_amd_iommu.c
@@ -185,10 +185,11 @@ static int __must_check amd_iommu_setup_
dte->ex = ivrs_dev->dte_allow_exclusion;
dte->sys_mgt = MASK_EXTR(ivrs_dev->device_flags,
ACPI_IVHD_SYSTEM_MGMT);
- if ( pci_ats_device(iommu->seg, bus, pdev->devfn) &&
+ if ( opt_ats > 0 &&
!ivrs_dev->block_ats &&
- iommu_has_cap(iommu, PCI_CAP_IOTLB_SHIFT) )
- dte->i = ats_enabled;
+ iommu_has_cap(iommu, PCI_CAP_IOTLB_SHIFT) &&
+ pci_ats_device(iommu->seg, bus, pdev->devfn) )
+ dte->i = true;
spin_unlock_irqrestore(&iommu->lock, flags);
@@ -248,10 +249,11 @@ static int __must_check amd_iommu_setup_
ASSERT(dte->sys_mgt == MASK_EXTR(ivrs_dev->device_flags,
ACPI_IVHD_SYSTEM_MGMT));
- if ( pci_ats_device(iommu->seg, bus, pdev->devfn) &&
+ if ( opt_ats > 0 &&
!ivrs_dev->block_ats &&
- iommu_has_cap(iommu, PCI_CAP_IOTLB_SHIFT) )
- ASSERT(dte->i == ats_enabled);
+ iommu_has_cap(iommu, PCI_CAP_IOTLB_SHIFT) &&
+ pci_ats_device(iommu->seg, bus, pdev->devfn) )
+ ASSERT(dte->i);
spin_unlock_irqrestore(&iommu->lock, flags);
@@ -268,9 +270,10 @@ static int __must_check amd_iommu_setup_
ASSERT(pcidevs_locked());
- if ( pci_ats_device(iommu->seg, bus, pdev->devfn) &&
+ if ( opt_ats > 0 &&
!ivrs_dev->block_ats &&
iommu_has_cap(iommu, PCI_CAP_IOTLB_SHIFT) &&
+ pci_ats_device(iommu->seg, bus, pdev->devfn) &&
!pci_ats_enabled(iommu->seg, bus, pdev->devfn) )
{
if ( devfn == pdev->devfn )
--- a/xen/drivers/passthrough/ats.c
+++ b/xen/drivers/passthrough/ats.c
@@ -18,8 +18,8 @@
#include <xen/pci_regs.h>
#include "ats.h"
-bool __read_mostly ats_enabled;
-boolean_param("ats", ats_enabled);
+int8_t __ro_after_init opt_ats = -1;
+boolean_param("ats", opt_ats);
int enable_ats_device(struct pci_dev *pdev, struct list_head *ats_list)
{
--- a/xen/drivers/passthrough/ats.h
+++ b/xen/drivers/passthrough/ats.h
@@ -22,7 +22,7 @@
#define ATS_QUEUE_DEPTH_MASK 0x1f
#define ATS_ENABLE (1<<15)
-extern bool ats_enabled;
+extern int8_t opt_ats;
int enable_ats_device(struct pci_dev *pdev, struct list_head *ats_list);
void disable_ats_device(struct pci_dev *pdev);
@@ -43,7 +43,7 @@ static inline int pci_ats_enabled(int se
static inline int pci_ats_device(int seg, int bus, int devfn)
{
- if ( !ats_enabled )
+ if ( !opt_ats )
return 0;
return pci_find_ext_capability(PCI_SBDF(seg, bus, devfn),
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -1543,7 +1543,7 @@ int domain_context_mapping_one(
}
context_set_address_root(lctxt, root);
- if ( ats_enabled && ecap_dev_iotlb(iommu->ecap) )
+ if ( opt_ats > 0 && ecap_dev_iotlb(iommu->ecap) )
context_set_translation_type(lctxt, CONTEXT_TT_DEV_IOTLB);
else
context_set_translation_type(lctxt, CONTEXT_TT_MULTI_LEVEL);
--- a/xen/drivers/passthrough/vtd/x86/ats.c
+++ b/xen/drivers/passthrough/vtd/x86/ats.c
@@ -46,7 +46,7 @@ int ats_device(const struct pci_dev *pde
struct acpi_drhd_unit *ats_drhd;
int pos;
- if ( !ats_enabled || !iommu_qinval )
+ if ( opt_ats <= 0 || !iommu_qinval )
return 0;
if ( !ecap_queued_inval(drhd->iommu->ecap) ||
