KVM: PPC: iommu: Unify TCE checking

This reworks helpers for checking TCE update parameters in way they
can be used in KVM.

This should cause no behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index d961425..8a8ce22 100644 (file)
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -296,11 +296,21 @@ static inline void iommu_restore(void)
 #endif
 
 /* The API to support IOMMU operations for VFIO */
-extern int iommu_tce_clear_param_check(struct iommu_table *tbl,
-               unsigned long ioba, unsigned long tce_value,
-               unsigned long npages);
-extern int iommu_tce_put_param_check(struct iommu_table *tbl,
-               unsigned long ioba, unsigned long tce);
+extern int iommu_tce_check_ioba(unsigned long page_shift,
+               unsigned long offset, unsigned long size,
+               unsigned long ioba, unsigned long npages);
+extern int iommu_tce_check_gpa(unsigned long page_shift,
+               unsigned long gpa);
+
+#define iommu_tce_clear_param_check(tbl, ioba, tce_value, npages) \
+               (iommu_tce_check_ioba((tbl)->it_page_shift,       \
+                               (tbl)->it_offset, (tbl)->it_size, \
+                               (ioba), (npages)) || (tce_value))
+#define iommu_tce_put_param_check(tbl, ioba, gpa)                 \
+               (iommu_tce_check_ioba((tbl)->it_page_shift,       \
+                               (tbl)->it_offset, (tbl)->it_size, \
+                               (ioba), 1) ||                     \
+               iommu_tce_check_gpa((tbl)->it_page_shift, (gpa)))
 
 extern void iommu_flush_tce(struct iommu_table *tbl);
 extern int iommu_take_ownership(struct iommu_table *tbl);

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 2e66800..4d079a2 100644 (file)
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -178,8 +178,10 @@ extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
                                struct kvm_create_spapr_tce_64 *args);
 extern struct kvmppc_spapr_tce_table *kvmppc_find_table(
                struct kvm *kvm, unsigned long liobn);
-extern long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt,
-               unsigned long ioba, unsigned long npages);
+#define kvmppc_ioba_validate(stt, ioba, npages)                         \
+               (iommu_tce_check_ioba((stt)->page_shift, (stt)->offset, \
+                               (stt)->size, (ioba), (npages)) ?        \
+                               H_PARAMETER : H_SUCCESS)
 extern long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *tt,
                unsigned long tce);
 extern long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa,

diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 5a3231f..f2b724c 100644 (file)
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -963,47 +963,36 @@ void iommu_flush_tce(struct iommu_table *tbl)
 }
 EXPORT_SYMBOL_GPL(iommu_flush_tce);
 
-int iommu_tce_clear_param_check(struct iommu_table *tbl,
-               unsigned long ioba, unsigned long tce_value,
-               unsigned long npages)
+int iommu_tce_check_ioba(unsigned long page_shift,
+               unsigned long offset, unsigned long size,
+               unsigned long ioba, unsigned long npages)
 {
-       /* tbl->it_ops->clear() does not support any value but 0 */
-       if (tce_value)
-               return -EINVAL;
+       unsigned long mask = (1UL << page_shift) - 1;
 
-       if (ioba & ~IOMMU_PAGE_MASK(tbl))
+       if (ioba & mask)
                return -EINVAL;
 
-       ioba >>= tbl->it_page_shift;
-       if (ioba < tbl->it_offset)
+       ioba >>= page_shift;
+       if (ioba < offset)
                return -EINVAL;
 
-       if ((ioba + npages) > (tbl->it_offset + tbl->it_size))
+       if ((ioba + 1) > (offset + size))
                return -EINVAL;
 
        return 0;
 }
-EXPORT_SYMBOL_GPL(iommu_tce_clear_param_check);
+EXPORT_SYMBOL_GPL(iommu_tce_check_ioba);
 
-int iommu_tce_put_param_check(struct iommu_table *tbl,
-               unsigned long ioba, unsigned long tce)
+int iommu_tce_check_gpa(unsigned long page_shift, unsigned long gpa)
 {
-       if (tce & ~IOMMU_PAGE_MASK(tbl))
-               return -EINVAL;
-
-       if (ioba & ~IOMMU_PAGE_MASK(tbl))
-               return -EINVAL;
-
-       ioba >>= tbl->it_page_shift;
-       if (ioba < tbl->it_offset)
-               return -EINVAL;
+       unsigned long mask = (1UL << page_shift) - 1;
 
-       if ((ioba + 1) > (tbl->it_offset + tbl->it_size))
+       if (gpa & mask)
                return -EINVAL;
 
        return 0;
 }
-EXPORT_SYMBOL_GPL(iommu_tce_put_param_check);
+EXPORT_SYMBOL_GPL(iommu_tce_check_gpa);
 
 long iommu_tce_xchg(struct iommu_table *tbl, unsigned long entry,
                unsigned long *hpa, enum dma_data_direction *direction)

diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c
index 0f145fc..440d3ab 100644 (file)
--- a/arch/powerpc/kvm/book3s_64_vio_hv.c
+++ b/arch/powerpc/kvm/book3s_64_vio_hv.c
@@ -61,27 +61,6 @@ struct kvmppc_spapr_tce_table *kvmppc_find_table(struct kvm *kvm,
 }
 EXPORT_SYMBOL_GPL(kvmppc_find_table);
 
-/*
- * Validates IO address.
- *
- * WARNING: This will be called in real-mode on HV KVM and virtual
- *          mode on PR KVM
- */
-long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt,
-               unsigned long ioba, unsigned long npages)
-{
-       unsigned long mask = (1ULL << stt->page_shift) - 1;
-       unsigned long idx = ioba >> stt->page_shift;
-
-       if ((ioba & mask) || (idx < stt->offset) ||
-                       (idx - stt->offset + npages > stt->size) ||
-                       (idx + npages < idx))
-               return H_PARAMETER;
-
-       return H_SUCCESS;
-}
-EXPORT_SYMBOL_GPL(kvmppc_ioba_validate);
-
 /*
  * Validates TCE address.
  * At the moment flags and page mask are validated.
@@ -95,10 +74,14 @@ EXPORT_SYMBOL_GPL(kvmppc_ioba_validate);
  */
 long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, unsigned long tce)
 {
-       unsigned long page_mask = ~((1ULL << stt->page_shift) - 1);
-       unsigned long mask = ~(page_mask | TCE_PCI_WRITE | TCE_PCI_READ);
+       unsigned long gpa = tce & ~(TCE_PCI_READ | TCE_PCI_WRITE);
+       enum dma_data_direction dir = iommu_tce_direction(tce);
+
+       /* Allow userspace to poison TCE table */
+       if (dir == DMA_NONE)
+               return H_SUCCESS;
 
-       if (tce & mask)
+       if (iommu_tce_check_gpa(stt->page_shift, gpa))
                return H_PARAMETER;
 
        return H_SUCCESS;