s390/dma: Allow per device dma ops

As virtio-ccw will have dma ops, we can no longer default to the
zPCI ones. Make use of dev_archdata to keep the dma_ops per device.
The pci devices now use that to override the default, and the
default is changed to use the noop ops for everything that does not
specify a device specific one.
To compile without PCI support we will enable HAS_DMA all the time,
via the default config in lib/Kconfig.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

5 files changed, 13 insertions, 9 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 3be9c832dec1..b29c66e77e32 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -124,6 +124,7 @@ config S390
         select HAVE_CMPXCHG_DOUBLE
         select HAVE_CMPXCHG_LOCAL
         select HAVE_DEBUG_KMEMLEAK
+        select HAVE_DMA_API_DEBUG
         select HAVE_DYNAMIC_FTRACE
         select HAVE_DYNAMIC_FTRACE_WITH_REGS
         select HAVE_FTRACE_MCOUNT_RECORD
@@ -619,10 +620,6 @@ config HAS_IOMEM
 config IOMMU_HELPER
         def_bool PCI
 
-config HAS_DMA
-        def_bool PCI
-        select HAVE_DMA_API_DEBUG
-
 config NEED_SG_DMA_LENGTH
         def_bool PCI
 
diff --git a/arch/s390/include/asm/device.h b/arch/s390/include/asm/device.h
index d8f9872b0e2d..4a9f35e0973f 100644
--- a/arch/s390/include/asm/device.h
+++ b/arch/s390/include/asm/device.h
@@ -3,5 +3,9 @@
  *
  * This file is released under the GPLv2
  */
-#include <asm-generic/device.h>
+struct dev_archdata {
+        struct dma_map_ops *dma_ops;
+};
 
+struct pdev_archdata {
+};
diff --git a/arch/s390/include/asm/dma-mapping.h b/arch/s390/include/asm/dma-mapping.h
index e64bfcb9702f..3249b7464889 100644
--- a/arch/s390/include/asm/dma-mapping.h
+++ b/arch/s390/include/asm/dma-mapping.h
@@ -11,11 +11,13 @@
 
 #define DMA_ERROR_CODE          (~(dma_addr_t) 0x0)
 
-extern struct dma_map_ops s390_dma_ops;
+extern struct dma_map_ops s390_pci_dma_ops;
 
 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 {
-        return &s390_dma_ops;
+        if (dev && dev->archdata.dma_ops)
+                return dev->archdata.dma_ops;
+        return &dma_noop_ops;
 }
 
 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 8f19c8f9d660..b63265a7f178 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -643,6 +643,7 @@ int pcibios_add_device(struct pci_dev *pdev)
 
         zdev->pdev = pdev;
         pdev->dev.groups = zpci_attr_groups;
+        pdev->dev.archdata.dma_ops = &s390_pci_dma_ops;
         zpci_map_resources(pdev);
 
         for (i = 0; i < PCI_BAR_COUNT; i++) {
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c
index 4638b93c7632..a79173ec54b9 100644
--- a/arch/s390/pci/pci_dma.c
+++ b/arch/s390/pci/pci_dma.c
@@ -544,7 +544,7 @@ static int __init dma_debug_do_init(void)
 }
 fs_initcall(dma_debug_do_init);
 
-struct dma_map_ops s390_dma_ops = {
+struct dma_map_ops s390_pci_dma_ops = {
         .alloc          = s390_dma_alloc,
         .free           = s390_dma_free,
         .map_sg         = s390_dma_map_sg,
@@ -555,7 +555,7 @@ struct dma_map_ops s390_dma_ops = {
         .is_phys        = 0,
         /* dma_supported is unconditionally true without a callback */
 };
-EXPORT_SYMBOL_GPL(s390_dma_ops);
+EXPORT_SYMBOL_GPL(s390_pci_dma_ops);
 
 static int __init s390_iommu_setup(char *str)
 {