s390/pci: use physical addresses in DMA tables

The entries in the DMA translation tables for our IOMMU must specify
physical addresses of either the next level table or the final page
to be mapped for DMA. Currently however the code simply passes the
virtual addresses of both. On the other hand we still need to walk the
tables via their virtual addresses so we need to do a phys_to_virt()
when setting the entries and a virt_to_phys() when getting them.
Similarly when passing the I/O translation anchor to the hardware we
must also specify its physical address.

As the DMA and IOMMU APIs we are implementing already use the correct
phys_addr_t type for the address to be mapped let's also thread this
through instead of treating it as just an unsigned long.

Note: this currently doesn't fix a real bug, since virtual addresses
are indentical to physical ones.

Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

1 files changed, 16 insertions, 13 deletions

diff --git a/arch/s390/include/asm/pci_dma.h b/arch/s390/include/asm/pci_dma.h
index 3b8e89d4578a..91e63426bdc5 100644
--- a/arch/s390/include/asm/pci_dma.h
+++ b/arch/s390/include/asm/pci_dma.h
@@ -97,23 +97,23 @@ static inline unsigned int calc_px(dma_addr_t ptr)
 	return ((unsigned long) ptr >> PAGE_SHIFT) & ZPCI_PT_MASK;
 }
 
-static inline void set_pt_pfaa(unsigned long *entry, void *pfaa)
+static inline void set_pt_pfaa(unsigned long *entry, phys_addr_t pfaa)
 {
 	*entry &= ZPCI_PTE_FLAG_MASK;
-	*entry |= ((unsigned long) pfaa & ZPCI_PTE_ADDR_MASK);
+	*entry |= (pfaa & ZPCI_PTE_ADDR_MASK);
 }
 
-static inline void set_rt_sto(unsigned long *entry, void *sto)
+static inline void set_rt_sto(unsigned long *entry, phys_addr_t sto)
 {
 	*entry &= ZPCI_RTE_FLAG_MASK;
-	*entry |= ((unsigned long) sto & ZPCI_RTE_ADDR_MASK);
+	*entry |= (sto & ZPCI_RTE_ADDR_MASK);
 	*entry |= ZPCI_TABLE_TYPE_RTX;
 }
 
-static inline void set_st_pto(unsigned long *entry, void *pto)
+static inline void set_st_pto(unsigned long *entry, phys_addr_t pto)
 {
 	*entry &= ZPCI_STE_FLAG_MASK;
-	*entry |= ((unsigned long) pto & ZPCI_STE_ADDR_MASK);
+	*entry |= (pto & ZPCI_STE_ADDR_MASK);
 	*entry |= ZPCI_TABLE_TYPE_SX;
 }
 
@@ -169,16 +169,19 @@ static inline int pt_entry_isvalid(unsigned long entry)
 
 static inline unsigned long *get_rt_sto(unsigned long entry)
 {
-	return ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_RTX)
-		? (unsigned long *) (entry & ZPCI_RTE_ADDR_MASK)
-		: NULL;
+	if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_RTX)
+		return phys_to_virt(entry & ZPCI_RTE_ADDR_MASK);
+	else
+		return NULL;
+
 }
 
 static inline unsigned long *get_st_pto(unsigned long entry)
 {
-	return ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_SX)
-		? (unsigned long *) (entry & ZPCI_STE_ADDR_MASK)
-		: NULL;
+	if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_SX)
+		return phys_to_virt(entry & ZPCI_STE_ADDR_MASK);
+	else
+		return NULL;
 }
 
 /* Prototypes */
@@ -186,7 +189,7 @@ void dma_free_seg_table(unsigned long);
 unsigned long *dma_alloc_cpu_table(void);
 void dma_cleanup_tables(unsigned long *);
 unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr);
-void dma_update_cpu_trans(unsigned long *entry, void *page_addr, int flags);
+void dma_update_cpu_trans(unsigned long *entry, phys_addr_t page_addr, int flags);
 
 extern const struct dma_map_ops s390_pci_dma_ops;