[dpdk-dev,RFC] vfio: allow to map other memory regions

diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index 640afd0887de..f0d8ae6ab4a3 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -126,6 +126,9 @@  ifeq ($(CONFIG_RTE_TOOLCHAIN_GCC),y)
 CFLAGS_eal_thread.o += -Wno-return-type
 endif
 
+SYMLINK-$(CONFIG_RTE_EXEC_ENV_LINUXAPP)-include = \
+	include/rte_iommu.h
+
 INC := rte_interrupts.h rte_kni_common.h rte_dom0_common.h
 
 SYMLINK-$(CONFIG_RTE_EXEC_ENV_LINUXAPP)-include/exec-env := \
diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c b/lib/librte_eal/linuxapp/eal/eal_vfio.c
index 53ac725d22e0..549c9824fdd7 100644
--- a/lib/librte_eal/linuxapp/eal/eal_vfio.c
+++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c
@@ -39,6 +39,7 @@ 
 #include <rte_log.h>
 #include <rte_memory.h>
 #include <rte_eal_memconfig.h>
+#include <rte_iommu.h>
 
 #include "eal_filesystem.h"
 #include "eal_vfio.h"
@@ -50,17 +51,19 @@ 
 static struct vfio_config vfio_cfg;
 
 static int vfio_type1_dma_map(int);
+static int vfio_type1_dma_mem_map(int, uint64_t, uint64_t, uint64_t, int);
 static int vfio_spapr_dma_map(int);
 static int vfio_noiommu_dma_map(int);
+static int vfio_noiommu_dma_mem_map(int, uint64_t, uint64_t, uint64_t, int);
 
 /* IOMMU types we support */
 static const struct vfio_iommu_type iommu_types[] = {
 	/* x86 IOMMU, otherwise known as type 1 */
-	{ RTE_VFIO_TYPE1, "Type 1", &vfio_type1_dma_map},
+	{ RTE_VFIO_TYPE1, "Type 1", &vfio_type1_dma_map, &vfio_type1_dma_mem_map},
 	/* ppc64 IOMMU, otherwise known as spapr */
-	{ RTE_VFIO_SPAPR, "sPAPR", &vfio_spapr_dma_map},
+	{ RTE_VFIO_SPAPR, "sPAPR", &vfio_spapr_dma_map, NULL},
 	/* IOMMU-less mode */
-	{ RTE_VFIO_NOIOMMU, "No-IOMMU", &vfio_noiommu_dma_map},
+	{ RTE_VFIO_NOIOMMU, "No-IOMMU", &vfio_noiommu_dma_map, &vfio_noiommu_dma_mem_map},
 };
 
 int
@@ -378,6 +381,8 @@  vfio_setup_device(const char *sysfs_base, const char *dev_addr,
 				clear_group(vfio_group_fd);
 				return -1;
 			}
+
+			vfio_cfg.vfio_iommu_type = t;
 		}
 	}
 
@@ -690,33 +695,61 @@  vfio_get_group_no(const char *sysfs_base,
 }
 
 static int
-vfio_type1_dma_map(int vfio_container_fd)
+vfio_type1_dma_mem_map(int vfio_container_fd, uint64_t vaddr, uint64_t iova,
+		       uint64_t len, int do_map)
 {
-	const struct rte_memseg *ms = rte_eal_get_physmem_layout();
-	int i, ret;
-
-	/* map all DPDK segments for DMA. use 1:1 PA to IOVA mapping */
-	for (i = 0; i < RTE_MAX_MEMSEG; i++) {
-		struct vfio_iommu_type1_dma_map dma_map;
-
-		if (ms[i].addr == NULL)
-			break;
+	struct vfio_iommu_type1_dma_map dma_map;
+	struct vfio_iommu_type1_dma_unmap dma_unmap;
+	int ret;
 
+	if (do_map != 0) {
 		memset(&dma_map, 0, sizeof(dma_map));
 		dma_map.argsz = sizeof(struct vfio_iommu_type1_dma_map);
-		dma_map.vaddr = ms[i].addr_64;
-		dma_map.size = ms[i].len;
-		dma_map.iova = ms[i].phys_addr;
+		dma_map.vaddr = vaddr;
+		dma_map.size = len;
+		dma_map.iova = iova;
 		dma_map.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;
 
 		ret = ioctl(vfio_container_fd, VFIO_IOMMU_MAP_DMA, &dma_map);
-
 		if (ret) {
 			RTE_LOG(ERR, EAL, "  cannot set up DMA remapping, "
 					  "error %i (%s)\n", errno,
 					  strerror(errno));
 			return -1;
 		}
+
+	} else {
+		memset(&dma_unmap, 0, sizeof(dma_unmap));
+		dma_unmap.argsz = sizeof(struct vfio_iommu_type1_dma_unmap);
+		dma_unmap.size = len;
+		dma_unmap.iova = iova;
+
+		ret = ioctl(vfio_container_fd, VFIO_IOMMU_UNMAP_DMA, &dma_unmap);
+		if (ret) {
+			RTE_LOG(ERR, EAL, "  cannot clear DMA remapping, "
+					  "error %i (%s)\n", errno,
+					  strerror(errno));
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+vfio_type1_dma_map(int vfio_container_fd)
+{
+	const struct rte_memseg *ms = rte_eal_get_physmem_layout();
+	int i;
+
+	/* map all DPDK segments for DMA. use 1:1 PA to IOVA mapping */
+	for (i = 0; i < RTE_MAX_MEMSEG; i++) {
+		if (ms[i].addr == NULL)
+			break;
+
+		if (vfio_type1_dma_mem_map(vfio_container_fd, ms[i].addr_64,
+					   ms[i].phys_addr, ms[i].len, 1))
+			return 1;
 	}
 
 	return 0;
@@ -816,4 +849,64 @@  vfio_noiommu_dma_map(int __rte_unused vfio_container_fd)
 	return 0;
 }
 
+static int
+vfio_noiommu_dma_mem_map(int __rte_unused vfio_container_fd,
+			 uint64_t __rte_unused vaddr,
+			 uint64_t __rte_unused iova, uint64_t __rte_unused len,
+			 int __rte_unused do_map)
+{
+	/* No-IOMMU mode does not need DMA mapping */
+	return 0;
+}
+
+static int
+vfio_dma_mem_map(uint64_t vaddr, uint64_t iova,
+		       uint64_t len, int do_map)
+{
+	const struct vfio_iommu_type *t = vfio_cfg.vfio_iommu_type;
+
+	if (!t) {
+		RTE_LOG(ERR, EAL, "  VFIO support not initialized\n");
+		return -1;
+	}
+
+	if (!t->dma_user_map_func) {
+		RTE_LOG(ERR, EAL,
+			"  VFIO custom DMA region maping not supported by IOMMU %s\n",
+			t->name);
+		return -1;
+	}
+
+	return t->dma_user_map_func(vfio_cfg.vfio_container_fd, vaddr, iova,
+				    len, do_map);
+}
+
+int
+rte_iommu_dma_map(uint64_t vaddr, uint64_t iova, uint64_t len)
+{
+	return vfio_dma_mem_map(vaddr, iova, len, 1);
+}
+
+int
+rte_iommu_dma_unmap(uint64_t vaddr, uint64_t iova, uint64_t len)
+{
+	return vfio_dma_mem_map(vaddr, iova, len, 0);
+}
+
+#else
+
+int
+rte_iommu_dma_map(uint64_t __rte_unused vaddr, __rte_unused uint64_t iova,
+		  __rte_unused uint64_t len)
+{
+	return 0;
+}
+
+int
+rte_iommu_dma_unmap(uint64_t __rte_unused vaddr, uint64_t __rte_unused iova,
+		    __rte_unused uint64_t len)
+{
+	return 0;
+}
+
 #endif
diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.h b/lib/librte_eal/linuxapp/eal/eal_vfio.h
index 5ff63e5d7579..b1d7dd6496df 100644
--- a/lib/librte_eal/linuxapp/eal/eal_vfio.h
+++ b/lib/librte_eal/linuxapp/eal/eal_vfio.h
@@ -141,6 +141,7 @@  struct vfio_config {
 	int vfio_enabled;
 	int vfio_container_fd;
 	int vfio_active_groups;
+	const struct vfio_iommu_type *vfio_iommu_type;
 	struct vfio_group vfio_groups[VFIO_MAX_GROUPS];
 };
 
@@ -157,10 +158,19 @@  struct vfio_config {
  * */
 typedef int (*vfio_dma_func_t)(int);
 
+/* Custom memory region DMA mapping function prototype.
+ * Takes VFIO container fd, virtual address, phisical address, length and
+ * operation type (0 to unmap 1 for map) as a parameters.
+ * Returns 0 on success, -1 on error.
+ **/
+typedef int (*vfio_dma_user_func_t)(int fd, uint64_t vaddr, uint64_t iova,
+				   uint64_t len, int do_map);
+
 struct vfio_iommu_type {
 	int type_id;
 	const char *name;
 	vfio_dma_func_t dma_map_func;
+	vfio_dma_user_func_t dma_user_map_func;
 };
 
 /* pick IOMMU type. returns a pointer to vfio_iommu_type or NULL for error */
diff --git a/lib/librte_eal/linuxapp/eal/include/rte_iommu.h b/lib/librte_eal/linuxapp/eal/include/rte_iommu.h
new file mode 100644
index 000000000000..4036db12dd96
--- /dev/null
+++ b/lib/librte_eal/linuxapp/eal/include/rte_iommu.h
@@ -0,0 +1,76 @@ 
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2017 Intel Corporation. All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RTE_IOMMU_H_
+#define _RTE_IOMMU_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Register memory region in current IOMMU to enable DMA.
+ *
+ * @param vaddr
+ *   Start of process virtual address.
+ * @param iova
+ *   Start of IO virtual address.
+ * @param len
+ *   Length of memory region.
+ * @return
+ *   - On success, zero.
+ *   - On failure, a negative value.
+ */
+int
+rte_iommu_dma_map(uint64_t vaddr, uint64_t iova, uint64_t len);
+
+/**
+ * Unregister previously registered memory region.
+ *
+ * @param vaddr
+ *   Start of process virtual address.
+ * @param iova
+ *   Start of IO virtual address.
+ * @param len
+ *   Length of memory region.
+ * @return
+ *   - On success, zero.
+ *   - On failure, a negative value.
+ */
+int
+rte_iommu_dma_unmap(uint64_t vaddr, uint64_t iova, uint64_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_IOMMU_H_ */
diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
index 670bab3a5ed6..e22dc37d6f46 100644
--- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
@@ -198,3 +198,10 @@  DPDK_17.05 {
 	vfio_get_group_no;
 
 } DPDK_17.02;
+
+DPDK_17.08 {
+	global:
+
+	rte_iommu_dma_map;
+	rte_iommu_dma_unmap
+} DPDK_17.05