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, 4 insertions, 6 deletions

diff --git a/tests/rtl8139-test.c b/tests/rtl8139-test.c
index c2f601a380..7de7dc45ae 100644
--- a/tests/rtl8139-test.c
+++ b/tests/rtl8139-test.c
@@ -22,7 +22,7 @@ static void nop(void)
 
 static QPCIBus *pcibus;
 static QPCIDevice *dev;
-static void *dev_base;
+static QPCIBar dev_bar;
 
 static void save_fn(QPCIDevice *dev, int devfn, void *data)
 {
@@ -45,14 +45,14 @@ static QPCIDevice *get_device(void)
 #define PORT(name, len, val) \
 static unsigned __attribute__((unused)) in_##name(void) \
 { \
-    unsigned res = qpci_io_read##len(dev, dev_base+(val)); \
+    unsigned res = qpci_io_read##len(dev, dev_bar, (val));     \
     g_test_message("*%s -> %x\n", #name, res); \
     return res; \
 } \
 static void out_##name(unsigned v) \
 { \
     g_test_message("%x -> *%s\n", v, #name); \
-    qpci_io_write##len(dev, dev_base+(val), v); \
+    qpci_io_write##len(dev, dev_bar, (val), v);        \
 }
 
 PORT(Timer, l, 0x48)
@@ -186,9 +186,7 @@ static void test_init(void)
 
     dev = get_device();
 
-    dev_base = qpci_iomap(dev, 0, &barsize);
-
-    g_assert(dev_base != NULL);
+    dev_bar = qpci_iomap(dev, 0, &barsize);
 
     qpci_device_enable(dev);