[dpdk-dev,07/12] lib/librte_vhost: split set_memory_table into two parts

Message ID 1422599787-12009-8-git-send-email-huawei.xie@intel.com (mailing list archive)
State Superseded, archived
Headers

Commit Message

Huawei Xie Jan. 30, 2015, 6:36 a.m. UTC
set_memory_table message is processed in two places.
* cuse_set_memory_table in virtio-net-cdev.c
* set_memory_table in virtio-net.c

vhost-cuse or vhost-user receives set_memory_region message from qemu,
maps guest memory into current process, prepares valid memory regions,
and then passes valid regions to set_memory_table ops provided by virtio-net.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 lib/librte_vhost/Makefile                     |   2 +-
 lib/librte_vhost/vhost-net.h                  |   5 +-
 lib/librte_vhost/vhost_cuse/vhost-net-cdev.c  |   7 +-
 lib/librte_vhost/vhost_cuse/virtio-net-cdev.c |  85 +++++++
 lib/librte_vhost/vhost_cuse/virtio-net-cdev.h |  45 ++++
 lib/librte_vhost/virtio-net.c                 | 306 +-------------------------
 6 files changed, 145 insertions(+), 305 deletions(-)
 create mode 100644 lib/librte_vhost/vhost_cuse/virtio-net-cdev.h
  

Patch

diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
index 6fe7471..92ab9a6 100644
--- a/lib/librte_vhost/Makefile
+++ b/lib/librte_vhost/Makefile
@@ -37,7 +37,7 @@  LIB = librte_vhost.a
 CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -I vhost_cuse -O3 -D_FILE_OFFSET_BITS=64 -lfuse
 LDFLAGS += -lfuse
 # all source are stored in SRCS-y
-SRCS-$(CONFIG_RTE_LIBRTE_VHOST) := vhost_cuse/vhost-net-cdev.c vhost_cuse/eventfd_copy.c virtio-net.c vhost_rxtx.c
+SRCS-$(CONFIG_RTE_LIBRTE_VHOST) := vhost_cuse/vhost-net-cdev.c vhost_cuse/virtio-net-cdev.c vhost_cuse/eventfd_copy.c virtio-net.c vhost_rxtx.c
 
 # install includes
 SYMLINK-$(CONFIG_RTE_LIBRTE_VHOST)-include += rte_virtio_net.h
diff --git a/lib/librte_vhost/vhost-net.h b/lib/librte_vhost/vhost-net.h
index 03a5c57..11737cc 100644
--- a/lib/librte_vhost/vhost-net.h
+++ b/lib/librte_vhost/vhost-net.h
@@ -41,6 +41,8 @@ 
 
 #include <rte_log.h>
 
+#define VHOST_MEMORY_MAX_NREGIONS 8
+
 /* Macros for printing using RTE_LOG */
 #define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
 #define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER1
@@ -92,7 +94,8 @@  struct vhost_net_device_ops {
 	int (*get_features)(struct vhost_device_ctx, uint64_t *);
 	int (*set_features)(struct vhost_device_ctx, uint64_t *);
 
-	int (*set_mem_table)(struct vhost_device_ctx, const void *, uint32_t);
+	int (*set_mem_table)(struct vhost_device_ctx,
+		const struct virtio_memory_regions *, uint32_t nregions);
 
 	int (*set_vring_num)(struct vhost_device_ctx, struct vhost_vring_state *);
 	int (*set_vring_addr)(struct vhost_device_ctx, struct vhost_vring_addr *);
diff --git a/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c b/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c
index e7794b0..72609a3 100644
--- a/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c
+++ b/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c
@@ -44,6 +44,7 @@ 
 #include <rte_string_fns.h>
 #include <rte_virtio_net.h>
 
+#include "virtio-net-cdev.h"
 #include "vhost-net.h"
 #include "eventfd_copy.h"
 
@@ -57,7 +58,7 @@  static const char cuse_device_name[] = "/dev/cuse";
 static const char default_cdev[] = "vhost-net";
 
 static struct fuse_session *session;
-static struct vhost_net_device_ops const *ops;
+struct vhost_net_device_ops const *ops;
 
 /*
  * Returns vhost_device_ctx from given fuse_req_t. The index is populated later
@@ -247,8 +248,8 @@  vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
 			break;
 
 		default:
-			result = ops->set_mem_table(ctx,
-					in_buf, mem_temp.nregions);
+			result = cuse_set_mem_table(ctx, in_buf,
+				mem_temp.nregions);
 			if (result)
 				fuse_reply_err(req, EINVAL);
 			else
diff --git a/lib/librte_vhost/vhost_cuse/virtio-net-cdev.c b/lib/librte_vhost/vhost_cuse/virtio-net-cdev.c
index 58ac3dd..edcbc10 100644
--- a/lib/librte_vhost/vhost_cuse/virtio-net-cdev.c
+++ b/lib/librte_vhost/vhost_cuse/virtio-net-cdev.c
@@ -47,7 +47,11 @@ 
 
 #include <rte_log.h>
 
+#include "rte_virtio_net.h"
 #include "vhost-net.h"
+#include "virtio-net-cdev.h"
+
+extern struct vhost_net_device_ops const *ops;
 
 /* Line size for reading maps file. */
 static const uint32_t BUFSIZE = PATH_MAX;
@@ -253,3 +257,84 @@  host_memory_map(pid_t pid, uint64_t addr,
 
 	return 0;
 }
+
+int
+cuse_set_mem_table(struct vhost_device_ctx ctx,
+	const struct vhost_memory *mem_regions_addr, uint32_t nregions)
+{
+	uint64_t size = offsetof(struct vhost_memory, regions);
+	uint32_t idx, valid_regions;
+	struct virtio_memory_regions regions[VHOST_MEMORY_MAX_NREGIONS];
+	struct vhost_memory_region *mem_regions = (void *)(uintptr_t)
+		((uint64_t)(uintptr_t)mem_regions_addr + size);
+	uint64_t base_address = 0, mapped_address, mapped_size;
+
+	for (idx = 0; idx < nregions; idx++) {
+		regions[idx].guest_phys_address =
+			mem_regions[idx].guest_phys_addr;
+		regions[idx].guest_phys_address_end =
+			regions[idx].guest_phys_address +
+			mem_regions[idx].memory_size;
+		regions[idx].memory_size =
+			mem_regions[idx].memory_size;
+		regions[idx].userspace_address =
+			mem_regions[idx].userspace_addr;
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"REGION: %u - GPA: %p - QVA: %p - SIZE (%"PRIu64")\n",
+			idx,
+			(void *)(uintptr_t)regions[idx].guest_phys_address,
+			(void *)(uintptr_t)regions[idx].userspace_address,
+			regions[idx].memory_size);
+
+		/*set the base address mapping*/
+		if (regions[idx].guest_phys_address == 0x0) {
+			base_address =
+				regions[idx].userspace_address;
+			/* Map VM memory file */
+			if (host_memory_map(ctx.pid, base_address,
+				&mapped_address, &mapped_size) != 0) {
+				return -1;
+			}
+		}
+	}
+
+	/* Check that we have a valid base address. */
+	if (base_address == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"Failed to find base address of qemu memory file.\n");
+		return -1;
+	}
+
+	valid_regions = nregions;
+	for (idx = 0; idx < nregions; idx++) {
+		if ((regions[idx].userspace_address < base_address) ||
+			(regions[idx].userspace_address >
+			(base_address + mapped_size)))
+			valid_regions--;
+	}
+
+	if (valid_regions != nregions) {
+		valid_regions = 0;
+		for (idx = nregions; 0 != idx--; ) {
+			if ((regions[idx].userspace_address < base_address) ||
+			(regions[idx].userspace_address >
+			(base_address + mapped_size))) {
+				memmove(&regions[idx], &regions[idx + 1],
+					sizeof(struct virtio_memory_regions) *
+					valid_regions);
+			} else
+				valid_regions++;
+		}
+	}
+
+	for (idx = 0; idx < valid_regions; idx++) {
+		regions[idx].address_offset =
+			mapped_address - base_address +
+			regions[idx].userspace_address -
+			regions[idx].guest_phys_address;
+	}
+
+	ops->set_mem_table(ctx, &regions[0], valid_regions);
+	return 0;
+}
diff --git a/lib/librte_vhost/vhost_cuse/virtio-net-cdev.h b/lib/librte_vhost/vhost_cuse/virtio-net-cdev.h
new file mode 100644
index 0000000..5ee81b1
--- /dev/null
+++ b/lib/librte_vhost/vhost_cuse/virtio-net-cdev.h
@@ -0,0 +1,45 @@ 
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   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 _VIRTIO_NET_CDEV_H
+#define _VIRTIO_NET_CDEV_H
+
+#include <stdint.h>
+#include <linux/vhost.h>
+
+#include "vhost-net.h"
+
+int
+cuse_set_mem_table(struct vhost_device_ctx ctx,
+	const struct vhost_memory *mem_regions_addr, uint32_t nregions);
+
+#endif
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
index da9e3a6..57a5801 100644
--- a/lib/librte_vhost/virtio-net.c
+++ b/lib/librte_vhost/virtio-net.c
@@ -31,8 +31,6 @@ 
  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <dirent.h>
-#include <fuse/cuse_lowlevel.h>
 #include <linux/vhost.h>
 #include <linux/virtio_net.h>
 #include <stddef.h>
@@ -72,26 +70,6 @@  static struct virtio_net_config_ll *ll_root;
 				(1ULL << VIRTIO_NET_F_CTRL_RX))
 static uint64_t VHOST_FEATURES = VHOST_SUPPORTED_FEATURES;
 
-/* Line size for reading maps file. */
-static const uint32_t BUFSIZE = PATH_MAX;
-
-/* Size of prot char array in procmap. */
-#define PROT_SZ 5
-
-/* Number of elements in procmap struct. */
-#define PROCMAP_SZ 8
-
-/* Structure containing information gathered from maps file. */
-struct procmap {
-	uint64_t va_start;	/* Start virtual address in file. */
-	uint64_t len;		/* Size of file. */
-	uint64_t pgoff;		/* Not used. */
-	uint32_t maj;		/* Not used. */
-	uint32_t min;		/* Not used. */
-	uint32_t ino;		/* Not used. */
-	char prot[PROT_SZ];	/* Not used. */
-	char fname[PATH_MAX];	/* File name. */
-};
 
 /*
  * Converts QEMU virtual address to Vhost virtual address. This function is
@@ -118,191 +96,6 @@  qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
 	return vhost_va;
 }
 
-/*
- * Locate the file containing QEMU's memory space and
- * map it to our address space.
- */
-static int
-host_memory_map(struct virtio_net *dev, struct virtio_memory *mem,
-	pid_t pid, uint64_t addr)
-{
-	struct dirent *dptr = NULL;
-	struct procmap procmap;
-	DIR *dp = NULL;
-	int fd;
-	int i;
-	char memfile[PATH_MAX];
-	char mapfile[PATH_MAX];
-	char procdir[PATH_MAX];
-	char resolved_path[PATH_MAX];
-	char *path = NULL;
-	FILE *fmap;
-	void *map;
-	uint8_t found = 0;
-	char line[BUFSIZE];
-	char dlm[] = "-   :   ";
-	char *str, *sp, *in[PROCMAP_SZ];
-	char *end = NULL;
-
-	/* Path where mem files are located. */
-	snprintf(procdir, PATH_MAX, "/proc/%u/fd/", pid);
-	/* Maps file used to locate mem file. */
-	snprintf(mapfile, PATH_MAX, "/proc/%u/maps", pid);
-
-	fmap = fopen(mapfile, "r");
-	if (fmap == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to open maps file for pid %d\n",
-			dev->device_fh, pid);
-		return -1;
-	}
-
-	/* Read through maps file until we find out base_address. */
-	while (fgets(line, BUFSIZE, fmap) != 0) {
-		str = line;
-		errno = 0;
-		/* Split line into fields. */
-		for (i = 0; i < PROCMAP_SZ; i++) {
-			in[i] = strtok_r(str, &dlm[i], &sp);
-			if ((in[i] == NULL) || (errno != 0)) {
-				fclose(fmap);
-				return -1;
-			}
-			str = NULL;
-		}
-
-		/* Convert/Copy each field as needed. */
-		procmap.va_start = strtoull(in[0], &end, 16);
-		if ((in[0] == '\0') || (end == NULL) || (*end != '\0') ||
-			(errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.len = strtoull(in[1], &end, 16);
-		if ((in[1] == '\0') || (end == NULL) || (*end != '\0') ||
-			(errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.pgoff = strtoull(in[3], &end, 16);
-		if ((in[3] == '\0') || (end == NULL) || (*end != '\0') ||
-			(errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.maj = strtoul(in[4], &end, 16);
-		if ((in[4] == '\0') || (end == NULL) || (*end != '\0') ||
-			(errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.min = strtoul(in[5], &end, 16);
-		if ((in[5] == '\0') || (end == NULL) || (*end != '\0') ||
-			(errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.ino = strtoul(in[6], &end, 16);
-		if ((in[6] == '\0') || (end == NULL) || (*end != '\0') ||
-			(errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		memcpy(&procmap.prot, in[2], PROT_SZ);
-		memcpy(&procmap.fname, in[7], PATH_MAX);
-
-		if (procmap.va_start == addr) {
-			procmap.len = procmap.len - procmap.va_start;
-			found = 1;
-			break;
-		}
-	}
-	fclose(fmap);
-
-	if (!found) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to find memory file in pid %d maps file\n",
-			dev->device_fh, pid);
-		return -1;
-	}
-
-	/* Find the guest memory file among the process fds. */
-	dp = opendir(procdir);
-	if (dp == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Cannot open pid %d process directory\n",
-			dev->device_fh, pid);
-		return -1;
-	}
-
-	found = 0;
-
-	/* Read the fd directory contents. */
-	while (NULL != (dptr = readdir(dp))) {
-		snprintf(memfile, PATH_MAX, "/proc/%u/fd/%s",
-				pid, dptr->d_name);
-		path = realpath(memfile, resolved_path);
-		if ((path == NULL) && (strlen(resolved_path) == 0)) {
-			RTE_LOG(ERR, VHOST_CONFIG,
-				"(%"PRIu64") Failed to resolve fd directory\n",
-				dev->device_fh);
-			closedir(dp);
-			return -1;
-		}
-		if (strncmp(resolved_path, procmap.fname,
-			strnlen(procmap.fname, PATH_MAX)) == 0) {
-			found = 1;
-			break;
-		}
-	}
-
-	closedir(dp);
-
-	if (found == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to find memory file for pid %d\n",
-			dev->device_fh, pid);
-		return -1;
-	}
-	/* Open the shared memory file and map the memory into this process. */
-	fd = open(memfile, O_RDWR);
-
-	if (fd == -1) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to open %s for pid %d\n",
-			dev->device_fh, memfile, pid);
-		return -1;
-	}
-
-	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE,
-		MAP_POPULATE|MAP_SHARED, fd, 0);
-	close(fd);
-
-	if (map == MAP_FAILED) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Error mapping the file %s for pid %d\n",
-			dev->device_fh, memfile, pid);
-		return -1;
-	}
-
-	/* Store the memory address and size in the device data structure */
-	mem->mapped_address = (uint64_t)(uintptr_t)map;
-	mem->mapped_size = procmap.len;
-
-	LOG_DEBUG(VHOST_CONFIG,
-		"(%"PRIu64") Mem File: %s->%s - Size: %llu - VA: %p\n",
-		dev->device_fh,
-		memfile, resolved_path,
-		(unsigned long long)mem->mapped_size, map);
-
-	return 0;
-}
 
 /*
  * Retrieves an entry from the devices configuration linked list.
@@ -651,14 +444,12 @@  set_features(struct vhost_device_ctx ctx, uint64_t *pu)
  * This includes storing offsets used to translate buffer addresses.
  */
 static int
-set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr,
-	uint32_t nregions)
+set_mem_table(struct vhost_device_ctx ctx,
+	const struct virtio_memory_regions *regions, uint32_t nregions)
 {
 	struct virtio_net *dev;
-	struct vhost_memory_region *mem_regions;
 	struct virtio_memory *mem;
-	uint64_t size = offsetof(struct vhost_memory, regions);
-	uint32_t regionidx, valid_regions;
+	uint32_t regionidx;
 
 	dev = get_device(ctx);
 	if (dev == NULL)
@@ -682,104 +473,19 @@  set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr,
 
 	mem->nregions = nregions;
 
-	mem_regions = (void *)(uintptr_t)
-			((uint64_t)(uintptr_t)mem_regions_addr + size);
-
 	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
 		/* Populate the region structure for each region. */
-		mem->regions[regionidx].guest_phys_address =
-			mem_regions[regionidx].guest_phys_addr;
-		mem->regions[regionidx].guest_phys_address_end =
-			mem->regions[regionidx].guest_phys_address +
-			mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].memory_size =
-			mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].userspace_address =
-			mem_regions[regionidx].userspace_addr;
-
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") REGION: %u - GPA: %p - QEMU VA: %p - SIZE (%"PRIu64")\n", dev->device_fh,
-			regionidx,
-			(void *)(uintptr_t)mem->regions[regionidx].guest_phys_address,
-			(void *)(uintptr_t)mem->regions[regionidx].userspace_address,
-			mem->regions[regionidx].memory_size);
-
-		/*set the base address mapping*/
+		mem->regions[regionidx] = regions[regionidx];
 		if (mem->regions[regionidx].guest_phys_address == 0x0) {
 			mem->base_address =
 				mem->regions[regionidx].userspace_address;
-			/* Map VM memory file */
-			if (host_memory_map(dev, mem, ctx.pid,
-				mem->base_address) != 0) {
-				free(mem);
-				return -1;
-			}
+			mem->mapped_address =
+				mem->regions[regionidx].address_offset;
 		}
 	}
 
-	/* Check that we have a valid base address. */
-	if (mem->base_address == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find base address of qemu memory file.\n", dev->device_fh);
-		free(mem);
-		return -1;
-	}
-
-	/*
-	 * Check if all of our regions have valid mappings.
-	 * Usually one does not exist in the QEMU memory file.
-	 */
-	valid_regions = mem->nregions;
-	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
-		if ((mem->regions[regionidx].userspace_address <
-			mem->base_address) ||
-			(mem->regions[regionidx].userspace_address >
-			(mem->base_address + mem->mapped_size)))
-				valid_regions--;
-	}
-
-	/*
-	 * If a region does not have a valid mapping,
-	 * we rebuild our memory struct to contain only valid entries.
-	 */
-	if (valid_regions != mem->nregions) {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Not all memory regions exist in the QEMU mem file. Re-populating mem structure\n",
-			dev->device_fh);
-
-		/*
-		 * Re-populate the memory structure with only valid regions.
-		 * Invalid regions are over-written with memmove.
-		 */
-		valid_regions = 0;
-
-		for (regionidx = mem->nregions; 0 != regionidx--;) {
-			if ((mem->regions[regionidx].userspace_address <
-				mem->base_address) ||
-				(mem->regions[regionidx].userspace_address >
-				(mem->base_address + mem->mapped_size))) {
-				memmove(&mem->regions[regionidx],
-					&mem->regions[regionidx + 1],
-					sizeof(struct virtio_memory_regions) *
-						valid_regions);
-			} else {
-				valid_regions++;
-			}
-		}
-	}
-	mem->nregions = valid_regions;
 	dev->mem = mem;
 
-	/*
-	 * Calculate the address offset for each region.
-	 * This offset is used to identify the vhost virtual address
-	 * corresponding to a QEMU guest physical address.
-	 */
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		dev->mem->regions[regionidx].address_offset =
-			dev->mem->regions[regionidx].userspace_address -
-				dev->mem->base_address +
-				dev->mem->mapped_address -
-				dev->mem->regions[regionidx].guest_phys_address;
-
-	}
 	return 0;
 }