Map the PBA in order to access it from the MSI-X read and write
handlers. Note that previously the handlers would pass the physical
host address into the {read,write}{l,q} handlers, which is wrong as
those expect a linear address.
Map the PBA using ioremap when the first access is performed. Note
that 32bit arches might want to abstract the call to ioremap into a
vPCI arch handler, so they can use a fixmap range to map the PBA.
Reported-by: Jan Beulich <jbeul...@suse.com>
Signed-off-by: Roger Pau Monné <roger....@citrix.com>
---
Cc: Alex Olson <this.is.a0l...@gmail.com>
---
Changes since v1:
- Also handle writes.
I don't seem to have a box with a driver that will try to access the
PBA, so I would consider this specific code path only build tested. At
least it doesn't seem to regress the current state of vPCI.
---
xen/drivers/vpci/msix.c | 55 +++++++++++++++++++++++++++++++++++++----
xen/drivers/vpci/vpci.c | 2 ++
xen/include/xen/vpci.h | 2 ++
3 files changed, 54 insertions(+), 5 deletions(-)
diff --git a/xen/drivers/vpci/msix.c b/xen/drivers/vpci/msix.c
index a1fa7a5f13..9fbc111ecc 100644
--- a/xen/drivers/vpci/msix.c
+++ b/xen/drivers/vpci/msix.c
@@ -198,8 +198,13 @@ static int cf_check msix_read(
if ( !access_allowed(msix->pdev, addr, len) )
return X86EMUL_OKAY;
+ spin_lock(&msix->pdev->vpci->lock);
if ( VMSIX_ADDR_IN_RANGE(addr, msix->pdev->vpci, VPCI_MSIX_PBA) )
{
+ struct vpci *vpci = msix->pdev->vpci;
+ paddr_t base = vmsix_table_addr(vpci, VPCI_MSIX_PBA);
+ unsigned int idx = addr - base;
+
/*
* Access to PBA.
*
@@ -207,25 +212,43 @@ static int cf_check msix_read(
* guest address space. If this changes the address will need to be
* translated.
*/
+
+ if ( !msix->pba )
+ {
+ msix->pba = ioremap(base, vmsix_table_size(vpci, VPCI_MSIX_PBA));
+ if ( !msix->pba )
+ {
+ /*
+ * If unable to map the PBA return all 1s (all pending): it's
+ * likely better to trigger spurious events than drop them.
+ */
+ spin_unlock(&vpci->lock);
+ gprintk(XENLOG_WARNING,
+ "%pp: unable to map MSI-X PBA, report all pending\n",
+ msix->pdev);
+ return X86EMUL_OKAY;
+ }
+ }
+
switch ( len )
{
case 4:
- *data = readl(addr);
+ *data = readl(msix->pba + idx);
break;
case 8:
- *data = readq(addr);
+ *data = readq(msix->pba + idx);
break;
default:
ASSERT_UNREACHABLE();
break;
}
+ spin_unlock(&vpci->lock);
return X86EMUL_OKAY;
}
- spin_lock(&msix->pdev->vpci->lock);
entry = get_entry(msix, addr);
offset = addr & (PCI_MSIX_ENTRY_SIZE - 1);
@@ -273,27 +296,49 @@ static int cf_check msix_write(
if ( !access_allowed(msix->pdev, addr, len) )
return X86EMUL_OKAY;
+ spin_lock(&msix->pdev->vpci->lock);
if ( VMSIX_ADDR_IN_RANGE(addr, msix->pdev->vpci, VPCI_MSIX_PBA) )
{
+ struct vpci *vpci = msix->pdev->vpci;
+ paddr_t base = vmsix_table_addr(vpci, VPCI_MSIX_PBA);
+ unsigned int idx = addr - base;
if ( !is_hardware_domain(d) )
+ {
/* Ignore writes to PBA for DomUs, it's behavior is undefined. */
+ spin_unlock(&vpci->lock);
return X86EMUL_OKAY;
+ }
+
+ if ( !msix->pba )
+ {
+ msix->pba = ioremap(base, vmsix_table_size(vpci, VPCI_MSIX_PBA));
+ if ( !msix->pba )
+ {
+ /* Unable to map the PBA, ignore write. */
+ spin_unlock(&vpci->lock);
+ gprintk(XENLOG_WARNING,
+ "%pp: unable to map MSI-X PBA, write ignored\n",
+ msix->pdev);
+ return X86EMUL_OKAY;
+ }
+ }
switch ( len )
{
case 4:
- writel(data, addr);
+ writel(data, msix->pba + idx);
break;
case 8:
- writeq(data, addr);
+ writeq(data, msix->pba + idx);
break;
default:
ASSERT_UNREACHABLE();
break;
}
+ spin_unlock(&vpci->lock);
return X86EMUL_OKAY;
}
diff --git a/xen/drivers/vpci/vpci.c b/xen/drivers/vpci/vpci.c
index f3b32d66cb..9fb3c05b2b 100644
--- a/xen/drivers/vpci/vpci.c
+++ b/xen/drivers/vpci/vpci.c
@@ -51,6 +51,8 @@ void vpci_remove_device(struct pci_dev *pdev)
xfree(r);
}
spin_unlock(&pdev->vpci->lock);
+ if ( pdev->vpci->msix && pdev->vpci->msix->pba )
+ iounmap(pdev->vpci->msix->pba);
xfree(pdev->vpci->msix);
xfree(pdev->vpci->msi);
xfree(pdev->vpci);
diff --git a/xen/include/xen/vpci.h b/xen/include/xen/vpci.h
index bcad1516ae..c399b101ee 100644
--- a/xen/include/xen/vpci.h
+++ b/xen/include/xen/vpci.h
@@ -127,6 +127,8 @@ struct vpci {
bool enabled : 1;
/* Masked? */
bool masked : 1;
+ /* PBA map */
+ void *pba;
/* Entries. */
struct vpci_msix_entry {
uint64_t addr;
--
2.34.1
