libqos: Change PCI accessors to take opaque BAR handle

The usual use model for the libqos PCI functions is to map a specific PCI
BAR using qpci_iomap() then pass the returned token into IO accessor
functions.  This, and the fact that iomap() returns a (void *) which
actually contains a PCI space address, kind of suggests that the return
value from iomap is supposed to be an opaque token.

..except that the callers expect to be able to add offsets to it.  Which
also assumes the compiler will support pointer arithmetic on a (void *),
and treat it as working with byte offsets.

To clarify this situation change iomap() and the IO accessors to take
a definitely opaque BAR handle (enforced with a wrapper struct) along with
an offset within the BAR.  This changes both the functions and all the
callers.

There were a number of places that checked if iomap() returned non-NULL,
and or initialized it to NULL before hand.  Since iomap() already assert()s
if it fails to map the BAR, these tests were mostly pointless and are
removed.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>

1 files changed, 28 insertions, 18 deletions

diff --git a/tests/libqos/pci.h b/tests/libqos/pci.h
index 531e3f79e9..ed480614ff 100644
--- a/tests/libqos/pci.h
+++ b/tests/libqos/pci.h
@@ -21,6 +21,7 @@
 
 typedef struct QPCIDevice QPCIDevice;
 typedef struct QPCIBus QPCIBus;
+typedef struct QPCIBar QPCIBar;
 
 struct QPCIBus {
     uint8_t (*pio_readb)(QPCIBus *bus, uint32_t addr);
@@ -51,13 +52,17 @@ struct QPCIBus {
     uint64_t mmio_alloc_ptr, mmio_limit;
 };
 
+struct QPCIBar {
+    uint64_t addr;
+};
+
 struct QPCIDevice
 {
     QPCIBus *bus;
     int devfn;
     bool msix_enabled;
-    void *msix_table;
-    void *msix_pba;
+    QPCIBar msix_table_bar, msix_pba_bar;
+    uint64_t msix_table_off, msix_pba_off;
 };
 
 void qpci_device_foreach(QPCIBus *bus, int vendor_id, int device_id,
@@ -81,22 +86,27 @@ void qpci_config_writeb(QPCIDevice *dev, uint8_t offset, uint8_t value);
 void qpci_config_writew(QPCIDevice *dev, uint8_t offset, uint16_t value);
 void qpci_config_writel(QPCIDevice *dev, uint8_t offset, uint32_t value);
 
-uint8_t qpci_io_readb(QPCIDevice *dev, void *data);
-uint16_t qpci_io_readw(QPCIDevice *dev, void *data);
-uint32_t qpci_io_readl(QPCIDevice *dev, void *data);
-uint64_t qpci_io_readq(QPCIDevice *dev, void *data);
-
-void qpci_io_writeb(QPCIDevice *dev, void *data, uint8_t value);
-void qpci_io_writew(QPCIDevice *dev, void *data, uint16_t value);
-void qpci_io_writel(QPCIDevice *dev, void *data, uint32_t value);
-void qpci_io_writeq(QPCIDevice *dev, void *data, uint64_t value);
-
-void qpci_memread(QPCIDevice *bus, void *data, void *buf, size_t len);
-void qpci_memwrite(QPCIDevice *bus, void *data, const void *buf, size_t len);
-
-void *qpci_iomap(QPCIDevice *dev, int barno, uint64_t *sizeptr);
-void qpci_iounmap(QPCIDevice *dev, void *data);
-void *qpci_legacy_iomap(QPCIDevice *dev, uint16_t addr);
+uint8_t qpci_io_readb(QPCIDevice *dev, QPCIBar token, uint64_t off);
+uint16_t qpci_io_readw(QPCIDevice *dev, QPCIBar token, uint64_t off);
+uint32_t qpci_io_readl(QPCIDevice *dev, QPCIBar token, uint64_t off);
+uint64_t qpci_io_readq(QPCIDevice *dev, QPCIBar token, uint64_t off);
+
+void qpci_io_writeb(QPCIDevice *dev, QPCIBar token, uint64_t off,
+                    uint8_t value);
+void qpci_io_writew(QPCIDevice *dev, QPCIBar token, uint64_t off,
+                    uint16_t value);
+void qpci_io_writel(QPCIDevice *dev, QPCIBar token, uint64_t off,
+                    uint32_t value);
+void qpci_io_writeq(QPCIDevice *dev, QPCIBar token, uint64_t off,
+                    uint64_t value);
+
+void qpci_memread(QPCIDevice *bus, QPCIBar token, uint64_t off,
+                  void *buf, size_t len);
+void qpci_memwrite(QPCIDevice *bus, QPCIBar token, uint64_t off,
+                   const void *buf, size_t len);
+QPCIBar qpci_iomap(QPCIDevice *dev, int barno, uint64_t *sizeptr);
+void qpci_iounmap(QPCIDevice *dev, QPCIBar addr);
+QPCIBar qpci_legacy_iomap(QPCIDevice *dev, uint16_t addr);
 
 void qpci_plug_device_test(const char *driver, const char *id,
                            uint8_t slot, const char *opts);