1 files changed, 884 insertions, 0 deletions

diff --git a/src/dpdk_lib18/librte_ivshmem/rte_ivshmem.c b/src/dpdk_lib18/librte_ivshmem/rte_ivshmem.c
new file mode 100755
index 00000000..7ca55edb
--- /dev/null
+++ b/src/dpdk_lib18/librte_ivshmem/rte_ivshmem.c
@@ -0,0 +1,884 @@
+/*-
+ *   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.
+ */
+#include <fcntl.h>
+#include <limits.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <rte_eal_memconfig.h>
+#include <rte_memory.h>
+#include <rte_ivshmem.h>
+#include <rte_string_fns.h>
+#include <rte_common.h>
+#include <rte_log.h>
+#include <rte_debug.h>
+#include <rte_spinlock.h>
+#include <rte_common.h>
+#include <rte_malloc.h>
+
+#include "rte_ivshmem.h"
+
+#define IVSHMEM_CONFIG_FILE_FMT "/var/run/.dpdk_ivshmem_metadata_%s"
+#define IVSHMEM_QEMU_CMD_LINE_HEADER_FMT "-device ivshmem,size=%" PRIu64 "M,shm=fd%s"
+#define IVSHMEM_QEMU_CMD_FD_FMT ":%s:0x%" PRIx64 ":0x%" PRIx64
+#define IVSHMEM_QEMU_CMDLINE_BUFSIZE 1024
+#define IVSHMEM_MAX_PAGES (1 << 12)
+#define adjacent(x,y) (((x).phys_addr+(x).len)==(y).phys_addr)
+#define METADATA_SIZE_ALIGNED \
+	(RTE_ALIGN_CEIL(sizeof(struct rte_ivshmem_metadata),pagesz))
+
+#define GET_PAGEMAP_ADDR(in,addr,dlm,err)    \
+{                                      \
+	char *end;                         \
+	errno = 0;                         \
+	addr = strtoull((in), &end, 16);   \
+	if (errno != 0 || *end != (dlm)) { \
+		RTE_LOG(ERR, EAL, err);        \
+		goto error;                    \
+	}                                  \
+	(in) = end + 1;                    \
+}
+
+static int pagesz;
+
+struct memseg_cache_entry {
+	char filepath[PATH_MAX];
+	uint64_t offset;
+	uint64_t len;
+};
+
+struct ivshmem_config {
+	struct rte_ivshmem_metadata * metadata;
+	struct memseg_cache_entry memseg_cache[IVSHMEM_MAX_PAGES];
+		/**< account for multiple files per segment case */
+	struct flock lock;
+	rte_spinlock_t sl;
+};
+
+static struct ivshmem_config
+ivshmem_global_config[RTE_LIBRTE_IVSHMEM_MAX_METADATA_FILES];
+
+static rte_spinlock_t global_cfg_sl;
+
+static struct ivshmem_config *
+get_config_by_name(const char * name)
+{
+	struct rte_ivshmem_metadata * config;
+	unsigned i;
+
+	for (i = 0; i < RTE_DIM(ivshmem_global_config); i++) {
+		config = ivshmem_global_config[i].metadata;
+		if (config == NULL)
+			return NULL;
+		if (strncmp(name, config->name, IVSHMEM_NAME_LEN) == 0)
+			return &ivshmem_global_config[i];
+	}
+
+	return NULL;
+}
+
+static int
+overlap(const struct rte_memzone * s1, const struct rte_memzone * s2)
+{
+	uint64_t start1, end1, start2, end2;
+
+	start1 = s1->addr_64;
+	end1 = s1->addr_64 + s1->len;
+	start2 = s2->addr_64;
+	end2 = s2->addr_64 + s2->len;
+
+	if (start1 >= start2 && start1 < end2)
+		return 1;
+	if (start2 >= start1 && start2 < end1)
+		return 1;
+
+	return 0;
+}
+
+static struct rte_memzone *
+get_memzone_by_addr(const void * addr)
+{
+	struct rte_memzone * tmp, * mz;
+	struct rte_mem_config * mcfg;
+	int i;
+
+	mcfg = rte_eal_get_configuration()->mem_config;
+	mz = NULL;
+
+	/* find memzone for the ring */
+	for (i = 0; i < RTE_MAX_MEMZONE; i++) {
+		tmp = &mcfg->memzone[i];
+
+		if (tmp->addr_64 == (uint64_t) addr) {
+			mz = tmp;
+			break;
+		}
+	}
+
+	return mz;
+}
+
+static int
+entry_compare(const void * a, const void * b)
+{
+	const struct rte_ivshmem_metadata_entry * e1 =
+			(const struct rte_ivshmem_metadata_entry*) a;
+	const struct rte_ivshmem_metadata_entry * e2 =
+			(const struct rte_ivshmem_metadata_entry*) b;
+
+	/* move unallocated zones to the end */
+	if (e1->mz.addr == NULL && e2->mz.addr == NULL)
+		return 0;
+	if (e1->mz.addr == 0)
+		return 1;
+	if (e2->mz.addr == 0)
+		return -1;
+
+	return e1->mz.phys_addr > e2->mz.phys_addr;
+}
+
+/* fills hugepage cache entry for a given start virt_addr */
+static int
+get_hugefile_by_virt_addr(uint64_t virt_addr, struct memseg_cache_entry * e)
+{
+	uint64_t start_addr, end_addr;
+	char *start,*path_end;
+	char buf[PATH_MAX*2];
+	FILE *f;
+
+	start = NULL;
+	path_end = NULL;
+	start_addr = 0;
+
+	memset(e->filepath, 0, sizeof(e->filepath));
+
+	/* open /proc/self/maps */
+	f = fopen("/proc/self/maps", "r");
+	if (f == NULL) {
+		RTE_LOG(ERR, EAL, "cannot open /proc/self/maps!\n");
+		return -1;
+	}
+
+	/* parse maps */
+	while (fgets(buf, sizeof(buf), f) != NULL) {
+
+		/* get endptr to end of start addr */
+		start = buf;
+
+		GET_PAGEMAP_ADDR(start,start_addr,'-',
+				"Cannot find start address in maps!\n");
+
+		/* if start address is bigger than our address, skip */
+		if (start_addr > virt_addr)
+			continue;
+
+		GET_PAGEMAP_ADDR(start,end_addr,' ',
+				"Cannot find end address in maps!\n");
+
+		/* if end address is less than our address, skip */
+		if (end_addr <= virt_addr)
+			continue;
+
+		/* find where the path starts */
+		start = strstr(start, "/");
+
+		if (start == NULL)
+			continue;
+
+		/* at this point, we know that this is our map.
+		 * now let's find the file */
+		path_end = strstr(start, "\n");
+		break;
+	}
+
+	if (path_end == NULL) {
+		RTE_LOG(ERR, EAL, "Hugefile path not found!\n");
+		goto error;
+	}
+
+	/* calculate offset and copy the file path */
+	snprintf(e->filepath, RTE_PTR_DIFF(path_end, start) + 1, "%s", start);
+
+	e->offset = virt_addr - start_addr;
+
+	fclose(f);
+
+	return 0;
+error:
+	fclose(f);
+	return -1;
+}
+
+/*
+ * This is a complex function. What it does is the following:
+ *  1. Goes through metadata and gets list of hugepages involved
+ *  2. Sorts the hugepages by size (1G first)
+ *  3. Goes through metadata again and writes correct offsets
+ *  4. Goes through pages and finds out their filenames, offsets etc.
+ */
+static int
+build_config(struct rte_ivshmem_metadata * metadata)
+{
+	struct rte_ivshmem_metadata_entry * e_local;
+	struct memseg_cache_entry * ms_local;
+	struct rte_memseg pages[IVSHMEM_MAX_PAGES];
+	struct rte_ivshmem_metadata_entry *entry;
+	struct memseg_cache_entry * c_entry, * prev_entry;
+	struct ivshmem_config * config;
+	unsigned i, j, mz_iter, ms_iter;
+	uint64_t biggest_len;
+	int biggest_idx;
+
+	/* return error if we try to use an unknown config file */
+	config = get_config_by_name(metadata->name);
+	if (config == NULL) {
+		RTE_LOG(ERR, EAL, "Cannot find IVSHMEM config %s!\n", metadata->name);
+		goto fail_e;
+	}
+
+	memset(pages, 0, sizeof(pages));
+
+	e_local = malloc(sizeof(config->metadata->entry));
+	if (e_local == NULL)
+		goto fail_e;
+	ms_local = malloc(sizeof(config->memseg_cache));
+	if (ms_local == NULL)
+		goto fail_ms;
+
+
+	/* make local copies before doing anything */
+	memcpy(e_local, config->metadata->entry, sizeof(config->metadata->entry));
+	memcpy(ms_local, config->memseg_cache, sizeof(config->memseg_cache));
+
+	qsort(e_local, RTE_DIM(config->metadata->entry), sizeof(struct rte_ivshmem_metadata_entry),
+			entry_compare);
+
+	/* first pass - collect all huge pages */
+	for (mz_iter = 0; mz_iter < RTE_DIM(config->metadata->entry); mz_iter++) {
+
+		entry = &e_local[mz_iter];
+
+		uint64_t start_addr = RTE_ALIGN_FLOOR(entry->mz.addr_64,
+				entry->mz.hugepage_sz);
+		uint64_t offset = entry->mz.addr_64 - start_addr;
+		uint64_t len = RTE_ALIGN_CEIL(entry->mz.len + offset,
+				entry->mz.hugepage_sz);
+
+		if (entry->mz.addr_64 == 0 || start_addr == 0 || len == 0)
+			continue;
+
+		int start_page;
+
+		/* find first unused page - mz are phys_addr sorted so we don't have to
+		 * look out for holes */
+		for (i = 0; i < RTE_DIM(pages); i++) {
+
+			/* skip if we already have this page */
+			if (pages[i].addr_64 == start_addr) {
+				start_addr += entry->mz.hugepage_sz;
+				len -= entry->mz.hugepage_sz;
+				continue;
+			}
+			/* we found a new page */
+			else if (pages[i].addr_64 == 0) {
+				start_page = i;
+				break;
+			}
+		}
+		if (i == RTE_DIM(pages)) {
+			RTE_LOG(ERR, EAL, "Cannot find unused page!\n");
+			goto fail;
+		}
+
+		/* populate however many pages the memzone has */
+		for (i = start_page; i < RTE_DIM(pages) && len != 0; i++) {
+
+			pages[i].addr_64 = start_addr;
+			pages[i].len = entry->mz.hugepage_sz;
+			start_addr += entry->mz.hugepage_sz;
+			len -= entry->mz.hugepage_sz;
+		}
+		/* if there's still length left */
+		if (len != 0) {
+			RTE_LOG(ERR, EAL, "Not enough space for pages!\n");
+			goto fail;
+		}
+	}
+
+	/* second pass - sort pages by size */
+	for (i = 0; i < RTE_DIM(pages); i++) {
+
+		if (pages[i].addr == NULL)
+			break;
+
+		biggest_len = 0;
+		biggest_idx = -1;
+
+		/*
+		 * browse all entries starting at 'i', and find the
+		 * entry with the smallest addr
+		 */
+		for (j=i; j< RTE_DIM(pages); j++) {
+			if (pages[j].addr == NULL)
+					break;
+			if (biggest_len == 0 ||
+				pages[j].len > biggest_len) {
+				biggest_len = pages[j].len;
+				biggest_idx = j;
+			}
+		}
+
+		/* should not happen */
+		if (biggest_idx == -1) {
+			RTE_LOG(ERR, EAL, "Error sorting by size!\n");
+			goto fail;
+		}
+		if (i != (unsigned) biggest_idx) {
+			struct rte_memseg tmp;
+
+			memcpy(&tmp, &pages[biggest_idx], sizeof(struct rte_memseg));
+
+			/* we don't want to break contiguousness, so instead of just
+			 * swapping segments, we move all the preceding segments to the
+			 * right and then put the old segment @ biggest_idx in place of
+			 * segment @ i */
+			for (j = biggest_idx - 1; j >= i; j--) {
+				memcpy(&pages[j+1], &pages[j], sizeof(struct rte_memseg));
+				memset(&pages[j], 0, sizeof(struct rte_memseg));
+			}
+
+			/* put old biggest segment to its new place */
+			memcpy(&pages[i], &tmp, sizeof(struct rte_memseg));
+		}
+	}
+
+	/* third pass - write correct offsets */
+	for (mz_iter = 0; mz_iter < RTE_DIM(config->metadata->entry); mz_iter++) {
+
+		uint64_t offset = 0;
+
+		entry = &e_local[mz_iter];
+
+		if (entry->mz.addr_64 == 0)
+			break;
+
+		/* find page for current memzone */
+		for (i = 0; i < RTE_DIM(pages); i++) {
+			/* we found our page */
+			if (entry->mz.addr_64 >= pages[i].addr_64 &&
+					entry->mz.addr_64 < pages[i].addr_64 + pages[i].len) {
+				entry->offset = (entry->mz.addr_64 - pages[i].addr_64) +
+						offset;
+				break;
+			}
+			offset += pages[i].len;
+		}
+		if (i == RTE_DIM(pages)) {
+			RTE_LOG(ERR, EAL, "Page not found!\n");
+			goto fail;
+		}
+	}
+
+	ms_iter = 0;
+	prev_entry = NULL;
+
+	/* fourth pass - create proper memseg cache */
+	for (i = 0; i < RTE_DIM(pages) &&
+			ms_iter <= RTE_DIM(config->memseg_cache); i++) {
+		if (pages[i].addr_64 == 0)
+			break;
+
+
+		if (ms_iter == RTE_DIM(pages)) {
+			RTE_LOG(ERR, EAL, "The universe has collapsed!\n");
+			goto fail;
+		}
+
+		c_entry = &ms_local[ms_iter];
+		c_entry->len = pages[i].len;
+
+		if (get_hugefile_by_virt_addr(pages[i].addr_64, c_entry) < 0)
+			goto fail;
+
+		/* if previous entry has the same filename and is contiguous,
+		 * clear current entry and increase previous entry's length
+		 */
+		if (prev_entry != NULL &&
+				strncmp(c_entry->filepath, prev_entry->filepath,
+				sizeof(c_entry->filepath)) == 0 &&
+				prev_entry->offset + prev_entry->len == c_entry->offset) {
+			prev_entry->len += pages[i].len;
+			memset(c_entry, 0, sizeof(struct memseg_cache_entry));
+		}
+		else {
+			prev_entry = c_entry;
+			ms_iter++;
+		}
+	}
+
+	/* update current configuration with new valid data */
+	memcpy(config->metadata->entry, e_local, sizeof(config->metadata->entry));
+	memcpy(config->memseg_cache, ms_local, sizeof(config->memseg_cache));
+
+	free(ms_local);
+	free(e_local);
+
+	return 0;
+fail:
+	free(ms_local);
+fail_ms:
+	free(e_local);
+fail_e:
+	return -1;
+}
+
+static int
+add_memzone_to_metadata(const struct rte_memzone * mz,
+		struct ivshmem_config * config)
+{
+	struct rte_ivshmem_metadata_entry * entry;
+	unsigned i;
+
+	rte_spinlock_lock(&config->sl);
+
+	/* find free slot in this config */
+	for (i = 0; i < RTE_DIM(config->metadata->entry); i++) {
+		entry = &config->metadata->entry[i];
+
+		if (&entry->mz.addr_64 != 0 && overlap(mz, &entry->mz)) {
+			RTE_LOG(ERR, EAL, "Overlapping memzones!\n");
+			goto fail;
+		}
+
+		/* if addr is zero, the memzone is probably free */
+		if (entry->mz.addr_64 == 0) {
+			RTE_LOG(DEBUG, EAL, "Adding memzone '%s' at %p to metadata %s\n",
+					mz->name, mz->addr, config->metadata->name);
+			memcpy(&entry->mz, mz, sizeof(struct rte_memzone));
+
+			/* run config file parser */
+			if (build_config(config->metadata) < 0)
+				goto fail;
+
+			break;
+		}
+	}
+
+	/* if we reached the maximum, that means we have no place in config */
+	if (i == RTE_DIM(config->metadata->entry)) {
+		RTE_LOG(ERR, EAL, "No space left in IVSHMEM metadata %s!\n",
+				config->metadata->name);
+		goto fail;
+	}
+
+	rte_spinlock_unlock(&config->sl);
+	return 0;
+fail:
+	rte_spinlock_unlock(&config->sl);
+	return -1;
+}
+
+static int
+add_ring_to_metadata(const struct rte_ring * r,
+		struct ivshmem_config * config)
+{
+	struct rte_memzone * mz;
+
+	mz = get_memzone_by_addr(r);
+
+	if (!mz) {
+		RTE_LOG(ERR, EAL, "Cannot find memzone for ring!\n");
+		return -1;
+	}
+
+	return add_memzone_to_metadata(mz, config);
+}
+
+static int
+add_mempool_to_metadata(const struct rte_mempool * mp,
+		struct ivshmem_config * config)
+{
+	struct rte_memzone * mz;
+	int ret;
+
+	mz = get_memzone_by_addr(mp);
+	ret = 0;
+
+	if (!mz) {
+		RTE_LOG(ERR, EAL, "Cannot find memzone for mempool!\n");
+		return -1;
+	}
+
+	/* mempool consists of memzone and ring */
+	ret = add_memzone_to_metadata(mz, config);
+	if (ret < 0)
+		return -1;
+
+	return add_ring_to_metadata(mp->ring, config);
+}
+
+int
+rte_ivshmem_metadata_add_ring(const struct rte_ring * r, const char * name)
+{
+	struct ivshmem_config * config;
+
+	if (name == NULL || r == NULL)
+		return -1;
+
+	config = get_config_by_name(name);
+
+	if (config == NULL) {
+		RTE_LOG(ERR, EAL, "Cannot find IVSHMEM config %s!\n", name);
+		return -1;
+	}
+
+	return add_ring_to_metadata(r, config);
+}
+
+int
+rte_ivshmem_metadata_add_memzone(const struct rte_memzone * mz, const char * name)
+{
+	struct ivshmem_config * config;
+
+	if (name == NULL || mz == NULL)
+		return -1;
+
+	config = get_config_by_name(name);
+
+	if (config == NULL) {
+		RTE_LOG(ERR, EAL, "Cannot find IVSHMEM config %s!\n", name);
+		return -1;
+	}
+
+	return add_memzone_to_metadata(mz, config);
+}
+
+int
+rte_ivshmem_metadata_add_mempool(const struct rte_mempool * mp, const char * name)
+{
+	struct ivshmem_config * config;
+
+	if (name == NULL || mp == NULL)
+		return -1;
+
+	config = get_config_by_name(name);
+
+	if (config == NULL) {
+		RTE_LOG(ERR, EAL, "Cannot find IVSHMEM config %s!\n", name);
+		return -1;
+	}
+
+	return add_mempool_to_metadata(mp, config);
+}
+
+static inline void
+ivshmem_config_path(char *buffer, size_t bufflen, const char *name)
+{
+	snprintf(buffer, bufflen, IVSHMEM_CONFIG_FILE_FMT, name);
+}
+
+
+
+static inline
+void *ivshmem_metadata_create(const char *name, size_t size,
+		struct flock *lock)
+{
+	int retval, fd;
+	void *metadata_addr;
+	char pathname[PATH_MAX];
+
+	ivshmem_config_path(pathname, sizeof(pathname), name);
+
+	fd = open(pathname, O_RDWR | O_CREAT, 0660);
+	if (fd < 0) {
+		RTE_LOG(ERR, EAL, "Cannot open '%s'\n", pathname);
+		return NULL;
+	}
+
+	size = METADATA_SIZE_ALIGNED;
+
+	retval = fcntl(fd, F_SETLK, lock);
+	if (retval < 0){
+		close(fd);
+		RTE_LOG(ERR, EAL, "Cannot create lock on '%s'. Is another "
+				"process using it?\n", pathname);
+		return NULL;
+	}
+
+	retval = ftruncate(fd, size);
+	if (retval < 0){
+		close(fd);
+		RTE_LOG(ERR, EAL, "Cannot resize '%s'\n", pathname);
+		return NULL;
+	}
+
+	metadata_addr = mmap(NULL, size,
+				PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+
+	if (metadata_addr == MAP_FAILED){
+		RTE_LOG(ERR, EAL, "Cannot mmap memory for '%s'\n", pathname);
+
+		/* we don't care if we can't unlock */
+		fcntl(fd, F_UNLCK, lock);
+		close(fd);
+
+		return NULL;
+	}
+
+	return metadata_addr;
+}
+
+int rte_ivshmem_metadata_create(const char *name)
+{
+	struct ivshmem_config * ivshmem_config;
+	unsigned index;
+
+	if (pagesz == 0)
+		pagesz = getpagesize();
+
+	if (name == NULL)
+		return -1;
+
+	rte_spinlock_lock(&global_cfg_sl);
+
+	for (index = 0; index < RTE_DIM(ivshmem_global_config); index++) {
+		if (ivshmem_global_config[index].metadata == NULL) {
+			ivshmem_config = &ivshmem_global_config[index];
+			break;
+		}
+	}
+
+	if (index == RTE_DIM(ivshmem_global_config)) {
+		RTE_LOG(ERR, EAL, "Cannot create more ivshmem config files. "
+		"Maximum has been reached\n");
+		rte_spinlock_unlock(&global_cfg_sl);
+		return -1;
+	}
+
+	ivshmem_config->lock.l_type = F_WRLCK;
+	ivshmem_config->lock.l_whence = SEEK_SET;
+
+	ivshmem_config->lock.l_start = 0;
+	ivshmem_config->lock.l_len = METADATA_SIZE_ALIGNED;
+
+	ivshmem_global_config[index].metadata = ((struct rte_ivshmem_metadata *)
+			ivshmem_metadata_create(
+					name,
+					sizeof(struct rte_ivshmem_metadata),
+					&ivshmem_config->lock));
+
+	if (ivshmem_global_config[index].metadata == NULL) {
+		rte_spinlock_unlock(&global_cfg_sl);
+		return -1;
+	}
+
+	/* Metadata setup */
+	memset(ivshmem_config->metadata, 0, sizeof(struct rte_ivshmem_metadata));
+	ivshmem_config->metadata->magic_number = IVSHMEM_MAGIC;
+	snprintf(ivshmem_config->metadata->name,
+			sizeof(ivshmem_config->metadata->name), "%s", name);
+
+	rte_spinlock_unlock(&global_cfg_sl);
+
+	return 0;
+}
+
+int
+rte_ivshmem_metadata_cmdline_generate(char *buffer, unsigned size, const char *name)
+{
+	const struct memseg_cache_entry * ms_cache, *entry;
+	struct ivshmem_config * config;
+	char cmdline[IVSHMEM_QEMU_CMDLINE_BUFSIZE], *cmdline_ptr;
+	char cfg_file_path[PATH_MAX];
+	unsigned remaining_len, tmplen, iter;
+	uint64_t shared_mem_size, zero_size, total_size;
+
+	if (buffer == NULL || name == NULL)
+		return -1;
+
+	config = get_config_by_name(name);
+
+	if (config == NULL) {
+		RTE_LOG(ERR, EAL, "Config %s not found!\n", name);
+		return -1;
+	}
+
+	rte_spinlock_lock(&config->sl);
+
+	/* prepare metadata file path */
+	snprintf(cfg_file_path, sizeof(cfg_file_path), IVSHMEM_CONFIG_FILE_FMT,
+			config->metadata->name);
+
+	ms_cache = config->memseg_cache;
+
+	cmdline_ptr = cmdline;
+	remaining_len = sizeof(cmdline);
+
+	shared_mem_size = 0;
+	iter = 0;
+
+	while ((ms_cache[iter].len != 0) && (iter < RTE_DIM(config->metadata->entry))) {
+
+		entry = &ms_cache[iter];
+
+		/* Offset and sizes within the current pathname */
+		tmplen = snprintf(cmdline_ptr, remaining_len, IVSHMEM_QEMU_CMD_FD_FMT,
+				entry->filepath, entry->offset, entry->len);
+
+		shared_mem_size += entry->len;
+
+		cmdline_ptr = RTE_PTR_ADD(cmdline_ptr, tmplen);
+		remaining_len -= tmplen;
+
+		if (remaining_len == 0) {
+			RTE_LOG(ERR, EAL, "Command line too long!\n");
+			rte_spinlock_unlock(&config->sl);
+			return -1;
+		}
+
+		iter++;
+	}
+
+	total_size = rte_align64pow2(shared_mem_size + METADATA_SIZE_ALIGNED);
+	zero_size = total_size - shared_mem_size - METADATA_SIZE_ALIGNED;
+
+	/* add /dev/zero to command-line to fill the space */
+	tmplen = snprintf(cmdline_ptr, remaining_len, IVSHMEM_QEMU_CMD_FD_FMT,
+			"/dev/zero",
+			(uint64_t)0x0,
+			zero_size);
+
+	cmdline_ptr = RTE_PTR_ADD(cmdline_ptr, tmplen);
+	remaining_len -= tmplen;
+
+	if (remaining_len == 0) {
+		RTE_LOG(ERR, EAL, "Command line too long!\n");
+		rte_spinlock_unlock(&config->sl);
+		return -1;
+	}
+
+	/* add metadata file to the end of command-line */
+	tmplen = snprintf(cmdline_ptr, remaining_len, IVSHMEM_QEMU_CMD_FD_FMT,
+			cfg_file_path,
+			(uint64_t)0x0,
+			METADATA_SIZE_ALIGNED);
+
+	cmdline_ptr = RTE_PTR_ADD(cmdline_ptr, tmplen);
+	remaining_len -= tmplen;
+
+	if (remaining_len == 0) {
+		RTE_LOG(ERR, EAL, "Command line too long!\n");
+		rte_spinlock_unlock(&config->sl);
+		return -1;
+	}
+
+	/* if current length of the command line is bigger than the buffer supplied
+	 * by the user, or if command-line is bigger than what IVSHMEM accepts */
+	if ((sizeof(cmdline) - remaining_len) > size) {
+		RTE_LOG(ERR, EAL, "Buffer is too short!\n");
+		rte_spinlock_unlock(&config->sl);
+		return -1;
+	}
+	/* complete the command-line */
+	snprintf(buffer, size,
+			IVSHMEM_QEMU_CMD_LINE_HEADER_FMT,
+			total_size >> 20,
+			cmdline);
+
+	rte_spinlock_unlock(&config->sl);
+
+	return 0;
+}
+
+void
+rte_ivshmem_metadata_dump(FILE *f, const char *name)
+{
+	unsigned i = 0;
+	struct ivshmem_config * config;
+	struct rte_ivshmem_metadata_entry *entry;
+#ifdef RTE_LIBRTE_IVSHMEM_DEBUG
+	uint64_t addr;
+	uint64_t end, hugepage_sz;
+	struct memseg_cache_entry e;
+#endif
+
+	if (name == NULL)
+		return;
+
+	/* return error if we try to use an unknown config file */
+	config = get_config_by_name(name);
+	if (config == NULL) {
+		RTE_LOG(ERR, EAL, "Cannot find IVSHMEM config %s!\n", name);
+		return;
+	}
+
+	rte_spinlock_lock(&config->sl);
+
+	entry = &config->metadata->entry[0];
+
+	while (entry->mz.addr != NULL && i < RTE_DIM(config->metadata->entry)) {
+
+		fprintf(f, "Entry %u: name:<%-20s>, phys:0x%-15lx, len:0x%-15lx, "
+			"virt:%-15p, off:0x%-15lx\n",
+			i,
+			entry->mz.name,
+			entry->mz.phys_addr,
+			entry->mz.len,
+			entry->mz.addr,
+			entry->offset);
+		i++;
+
+#ifdef RTE_LIBRTE_IVSHMEM_DEBUG
+		fprintf(f, "\tHugepage files:\n");
+
+		hugepage_sz = entry->mz.hugepage_sz;
+		addr = RTE_ALIGN_FLOOR(entry->mz.addr_64, hugepage_sz);
+		end = addr + RTE_ALIGN_CEIL(entry->mz.len + (entry->mz.addr_64 - addr),
+				hugepage_sz);
+
+		for (; addr < end; addr += hugepage_sz) {
+			memset(&e, 0, sizeof(e));
+
+			get_hugefile_by_virt_addr(addr, &e);
+
+			fprintf(f, "\t0x%"PRIx64 "-0x%" PRIx64 " offset: 0x%" PRIx64 " %s\n",
+					addr, addr + hugepage_sz, e.offset, e.filepath);
+		}
+#endif
+		entry++;
+	}
+
+	rte_spinlock_unlock(&config->sl);
+}