[dpdk-dev] [PATCH] igb_uio: fix Xen compatibility with kernel 3.18

[Shu Shen <shu.shen@radisys.com>]

This patch fixes build failing with undefined symbol _PAGE_IOMAP with
kernel 3.18.

The Xen-specific _PAGE_IOMAP PTE flag was removed in kernel 3.18 and
could be used for other purpose in future. This patch ensures that
_PAGE_IOMAP flag is only used for kernels before 3.18.

Signed-off-by: Shu Shen <shu.shen@radisys.com>
---
 lib/librte_eal/linuxapp/igb_uio/compat.h  | 4 ++++
 lib/librte_eal/linuxapp/igb_uio/igb_uio.c | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/lib/librte_eal/linuxapp/igb_uio/compat.h b/lib/librte_eal/linuxapp/igb_uio/compat.h
index 9454382..c1d45a6 100644
--- a/lib/librte_eal/linuxapp/igb_uio/compat.h
+++ b/lib/librte_eal/linuxapp/igb_uio/compat.h
@@ -11,6 +11,10 @@
 #define pci_cfg_access_unlock pci_unblock_user_cfg_access
 #endif
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 18, 0)
+#define HAVE_PTE_MASK_PAGE_IOMAP
+#endif
+
 #ifndef PCI_MSIX_ENTRY_SIZE
 #define PCI_MSIX_ENTRY_SIZE             16
 #define  PCI_MSIX_ENTRY_LOWER_ADDR      0
diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
index 47ff2f3..60a2db1 100644
--- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
+++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
@@ -287,7 +287,9 @@ igbuio_dom0_mmap_phys(struct uio_info *info, struct vm_area_struct *vma)
 
 	idx = (int)vma->vm_pgoff;
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+#if defined(HAVE_PTE_MASK_PAGE_IOMAP)
 	vma->vm_page_prot.pgprot |= _PAGE_IOMAP;
+#endif
 
 	return remap_pfn_range(vma,
 			vma->vm_start,
-- 
1.9.1