[v12,14/15] xen/arm: vpci: permit access to guest vpci space

Commit Message

Stewart Hildebrand Jan. 9, 2024, 9:51 p.m. UTC

Move iomem_caps initialization earlier (before arch_domain_create()).

Signed-off-by: Stewart Hildebrand <[e-mail]>
---
Changes in v11:
* move both iomem_caps and irq_caps initializations earlier, along with NULL
  check

Changes in v10:
* fix off-by-one
* also permit access to GUEST_VPCI_PREFETCH_MEM_ADDR

Changes in v9:
* new patch

This is sort of a follow-up to:

  baa6ea700386 ("vpci: add permission checks to map_range()")

I don't believe we need a fixes tag since this depends on the vPCI p2m BAR
patches.
---
 xen/arch/arm/vpci.c |  9 +++++++++
 xen/common/domain.c | 12 ++++++------
 2 files changed, 15 insertions(+), 6 deletions(-)

Comments

Stewart Hildebrand Jan. 17, 2024, 3:03 a.m. UTC | #1

On 1/9/24 16:51, Stewart Hildebrand wrote:
> Move iomem_caps initialization earlier (before arch_domain_create()).
> 
> Signed-off-by: Stewart Hildebrand <[e-mail]>

Since the iomem_access_permitted() check over in ("vpci/header: program p2m with guest BAR view") was changed to use MFNs (it used GFNs in an earlier rev) this whole patch should be dropped. The toolstack already does what this patch was trying to do with XEN_DOMCTL_iomem_permission.

Patch

diff --git a/xen/arch/arm/vpci.c b/xen/arch/arm/vpci.c
index 348ba0fbc860..b6ef440f17b0 100644
--- a/xen/arch/arm/vpci.c
+++ b/xen/arch/arm/vpci.c
@@ -2,6 +2,7 @@ 
 /*
  * xen/arch/arm/vpci.c
  */
+#include <xen/iocap.h>
 #include <xen/sched.h>
 #include <xen/vpci.h>
 
@@ -115,8 +116,16 @@  int domain_vpci_init(struct domain *d)
             return ret;
     }
     else
+    {
         register_mmio_handler(d, &vpci_mmio_handler,
                               GUEST_VPCI_ECAM_BASE, GUEST_VPCI_ECAM_SIZE, NULL);
+        iomem_permit_access(d, paddr_to_pfn(GUEST_VPCI_MEM_ADDR),
+                            paddr_to_pfn(GUEST_VPCI_MEM_ADDR +
+                                         GUEST_VPCI_MEM_SIZE - 1));
+        iomem_permit_access(d, paddr_to_pfn(GUEST_VPCI_PREFETCH_MEM_ADDR),
+                            paddr_to_pfn(GUEST_VPCI_PREFETCH_MEM_ADDR +
+                                         GUEST_VPCI_PREFETCH_MEM_SIZE - 1));
+    }
 
     return 0;
 }
diff --git a/xen/common/domain.c b/xen/common/domain.c
index f6f557499660..8078d1ade690 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -693,6 +693,12 @@  struct domain *domain_create(domid_t domid,
         d->nr_pirqs = min(d->nr_pirqs, nr_irqs);
 
         radix_tree_init(&d->pirq_tree);
+
+        err = -ENOMEM;
+        d->iomem_caps = rangeset_new(d, "I/O Memory", RANGESETF_prettyprint_hex);
+        d->irq_caps   = rangeset_new(d, "Interrupts", 0);
+        if ( !d->iomem_caps || !d->irq_caps )
+            goto fail;
     }
 
     if ( (err = arch_domain_create(d, config, flags)) != 0 )
@@ -711,12 +717,6 @@  struct domain *domain_create(domid_t domid,
         watchdog_domain_init(d);
         init_status |= INIT_watchdog;
 
-        err = -ENOMEM;
-        d->iomem_caps = rangeset_new(d, "I/O Memory", RANGESETF_prettyprint_hex);
-        d->irq_caps   = rangeset_new(d, "Interrupts", 0);
-        if ( !d->iomem_caps || !d->irq_caps )
-            goto fail;
-
         if ( (err = xsm_domain_create(XSM_HOOK, d, config->ssidref)) != 0 )
             goto fail;