[dpdk-dev] [PATCH] vfio: don't silently drop VFIO support

[Stephen Hemminger]

The VFIO_PRESENT #define was a landmine and we hit it.
The DPDK has a config system and it should be used rather than
silently dropping a feature during build only to have it fail at
run time.

If VFIO is configured, and the kernel headers are not present
the build should fail. Rather than leaving developers puzzling
why the build system (with old kernel headers) produced non
functioning DPDK and their system (with new kernel headers) produced
correctly working DPDK.

As a matter of policy, really no code should be looking at
<linux/version.h> except for kernel drivers with compat files.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 lib/librte_eal/linuxapp/eal/Makefile               |  4 ++--
 lib/librte_eal/linuxapp/eal/eal_interrupts.c       | 10 +++++-----
 lib/librte_eal/linuxapp/eal/eal_pci.c              |  4 ++--
 lib/librte_eal/linuxapp/eal/eal_pci_init.h         |  2 +-
 lib/librte_eal/linuxapp/eal/eal_pci_vfio.c         |  3 ---
 lib/librte_eal/linuxapp/eal/eal_pci_vfio_mp_sync.c |  3 ---
 lib/librte_eal/linuxapp/eal/eal_vfio.h             |  1 -
 7 files changed, 10 insertions(+), 17 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index 01f7b70..abaf0da 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -64,8 +64,8 @@ SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_thread.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_log.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_pci.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_pci_uio.c
-SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_pci_vfio.c
-SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_pci_vfio_mp_sync.c
+SRCS-$(CONFIG_RTE_EAL_VFIO) += eal_pci_vfio.c
+SRCS-$(CONFIG_RTE_EAL_VFIO) += eal_pci_vfio_mp_sync.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_debug.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_lcore.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_timer.c
diff --git a/lib/librte_eal/linuxapp/eal/eal_interrupts.c b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
index 66deda2..55f41d2 100644
--- a/lib/librte_eal/linuxapp/eal/eal_interrupts.c
+++ b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
@@ -87,7 +87,7 @@ union intr_pipefds{
  */
 union rte_intr_read_buffer {
 	int uio_intr_count;              /* for uio device */
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 	uint64_t vfio_intr_count;        /* for vfio device */
 #endif
 	uint64_t timerfd_num;            /* for timerfd */
@@ -123,7 +123,7 @@ static struct rte_intr_source_list intr_sources;
 static pthread_t intr_thread;
 
 /* VFIO interrupts */
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 
 #define IRQ_SET_BUF_LEN  (sizeof(struct vfio_irq_set) + sizeof(int))
 
@@ -559,7 +559,7 @@ rte_intr_enable(struct rte_intr_handle *intr_handle)
 	/* not used at this moment */
 	case RTE_INTR_HANDLE_ALARM:
 		return -1;
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 	case RTE_INTR_HANDLE_VFIO_MSIX:
 		if (vfio_enable_msix(intr_handle))
 			return -1;
@@ -599,7 +599,7 @@ rte_intr_disable(struct rte_intr_handle *intr_handle)
 	/* not used at this moment */
 	case RTE_INTR_HANDLE_ALARM:
 		return -1;
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 	case RTE_INTR_HANDLE_VFIO_MSIX:
 		if (vfio_disable_msix(intr_handle))
 			return -1;
@@ -667,7 +667,7 @@ eal_intr_process_interrupts(struct epoll_event *events, int nfds)
 		case RTE_INTR_HANDLE_ALARM:
 			bytes_read = sizeof(buf.timerfd_num);
 			break;
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 		case RTE_INTR_HANDLE_VFIO_MSIX:
 		case RTE_INTR_HANDLE_VFIO_MSI:
 		case RTE_INTR_HANDLE_VFIO_LEGACY:
diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
index 9cb0ffd..5bc0254 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
@@ -571,7 +571,7 @@ pci_map_device(struct rte_pci_device *dev)
 	/* try mapping the NIC resources using VFIO if it exists */
 	switch (dev->kdrv) {
 	case RTE_KDRV_VFIO:
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 		if (pci_vfio_is_enabled())
 			ret = pci_vfio_map_resource(dev);
 #endif
@@ -771,7 +771,7 @@ rte_eal_pci_init(void)
 		RTE_LOG(ERR, EAL, "%s(): Cannot scan PCI bus\n", __func__);
 		return -1;
 	}
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 	pci_vfio_enable();
 
 	if (pci_vfio_is_enabled()) {
diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_init.h b/lib/librte_eal/linuxapp/eal/eal_pci_init.h
index aa7b755..e285204 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci_init.h
+++ b/lib/librte_eal/linuxapp/eal/eal_pci_init.h
@@ -78,7 +78,7 @@ void pci_unmap_resource(void *requested_addr, size_t size);
 void pci_uio_unmap_resource(struct rte_pci_device *dev);
 #endif /* RTE_LIBRTE_EAL_HOTPLUG */
 
-#ifdef VFIO_PRESENT
+#ifdef RTE_EAL_VFIO
 
 #define VFIO_MAX_GROUPS 64
 
diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
index aea1fb1..6a0fd08 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
@@ -59,8 +59,6 @@
  * This file is only compiled if CONFIG_RTE_EAL_VFIO is set to "y".
  */
 
-#ifdef VFIO_PRESENT
-
 #define PAGE_SIZE   (sysconf(_SC_PAGESIZE))
 #define PAGE_MASK   (~(PAGE_SIZE - 1))
 
@@ -909,4 +907,3 @@ pci_vfio_is_enabled(void)
 {
 	return vfio_cfg.vfio_enabled;
 }
-#endif
diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_vfio_mp_sync.c b/lib/librte_eal/linuxapp/eal/eal_pci_vfio_mp_sync.c
index fec7080..657fc2c 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci_vfio_mp_sync.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci_vfio_mp_sync.c
@@ -62,8 +62,6 @@
  * This file is only compiled if CONFIG_RTE_EAL_VFIO is set to "y".
  */
 
-#ifdef VFIO_PRESENT
-
 #define SOCKET_PATH_FMT "%s/.%s_mp_socket"
 #define CMSGLEN (CMSG_LEN(sizeof(int)))
 #define FD_TO_CMSGHDR(fd, chdr) \
@@ -391,4 +389,3 @@ pci_vfio_mp_sync_setup(void)
 	return 0;
 }
 
-#endif
diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.h b/lib/librte_eal/linuxapp/eal/eal_vfio.h
index 72ec3f6..0b4e362 100644
--- a/lib/librte_eal/linuxapp/eal/eal_vfio.h
+++ b/lib/librte_eal/linuxapp/eal/eal_vfio.h
@@ -52,7 +52,6 @@
 #define RTE_PCI_MSIX_FLAGS_QSIZE  PCI_MSIX_FLAGS_QSIZE
 #endif
 
-#define VFIO_PRESENT
 #endif /* kernel version */
 #endif /* RTE_EAL_VFIO */
 
-- 
2.1.4