[PATCH v3 1/2] bus/pci: fix vfio mode

[Gaetan Rivet <gaetan.rivet@6wind.com>]

From: Jerin Jacob <jerin.jacob@caviumnetworks.com>

Revert back to using VFIO_PRESENT as a marker to enable compilation
of VFIO-related segments.

Fixes: 279b581c897d ("vfio: expose functions")

Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Signed-off-by: Gaetan Rivet <gaetan.rivet@6wind.com>
---

In addition to simply re-defining VFIO_PRESENT, the previous #ifdef
removed in favor of RTE_EAL_VFIO must be switched back as well.

Not doing so would break compilation on kernels prior to 3.6.

Additionally, the following patch adds a warning for users.

This fix is left as-is, instead of a more involved solution like
Ferruh's. The reasoning behind it is that it should be made abundantly
clear that the VFIO_PRESENT symbol is defined in eal_vfio.h and
eal_vfio.h only, that it is a private EAL symbol that is currently
bleeding out of the EAL. It should be visible when those private symbols
will be removed from libs external to the EAL.

v3:

  - Fix build by include eal_vfio.h in pci_init.h and pci.c as well.

 drivers/bus/pci/linux/pci.c      | 1 +
 drivers/bus/pci/linux/pci_init.h | 4 +++-
 drivers/bus/pci/linux/pci_vfio.c | 3 ++-
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
index cdf8106..d0ce020 100644
--- a/drivers/bus/pci/linux/pci.c
+++ b/drivers/bus/pci/linux/pci.c
@@ -46,6 +46,7 @@
 
 #include "eal_private.h"
 #include "eal_filesystem.h"
+#include "eal_vfio.h"
 
 #include "private.h"
 #include "pci_init.h"
diff --git a/drivers/bus/pci/linux/pci_init.h b/drivers/bus/pci/linux/pci_init.h
index 99d7a2e..3290cee 100644
--- a/drivers/bus/pci/linux/pci_init.h
+++ b/drivers/bus/pci/linux/pci_init.h
@@ -38,6 +38,8 @@
 
 #include <rte_vfio.h>
 
+#include "eal_vfio.h"
+
 /** IO resource type: */
 #define IORESOURCE_IO         0x00000100
 #define IORESOURCE_MEM        0x00000200
@@ -74,7 +76,7 @@ void pci_uio_ioport_write(struct rte_pci_ioport *p,
 			  const void *data, size_t len, off_t offset);
 int pci_uio_ioport_unmap(struct rte_pci_ioport *p);
 
-#ifdef RTE_EAL_VFIO
+#ifdef VFIO_PRESENT
 
 #if LINUX_VERSION_CODE < KERNEL_VERSION(3, 10, 0)
 #define RTE_PCI_MSIX_TABLE_BIR    0x7
diff --git a/drivers/bus/pci/linux/pci_vfio.c b/drivers/bus/pci/linux/pci_vfio.c
index 360eed3..38d3792 100644
--- a/drivers/bus/pci/linux/pci_vfio.c
+++ b/drivers/bus/pci/linux/pci_vfio.c
@@ -48,6 +48,7 @@
 #include <rte_vfio.h>
 
 #include "eal_filesystem.h"
+#include "eal_vfio.h"
 
 #include "pci_init.h"
 #include "private.h"
@@ -62,7 +63,7 @@
  * This file is only compiled if CONFIG_RTE_EAL_VFIO is set to "y".
  */
 
-#ifdef RTE_EAL_VFIO
+#ifdef VFIO_PRESENT
 
 #define PAGE_SIZE   (sysconf(_SC_PAGESIZE))
 #define PAGE_MASK   (~(PAGE_SIZE - 1))
-- 
2.1.4