numam-dpdk/drivers/net/mlx4/mlx4_mr.c

/*-
 *   BSD LICENSE
 *
 *   Copyright 2017 6WIND S.A.
 *   Copyright 2017 Mellanox
 *
 *   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 6WIND S.A. 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,
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 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * @file
 * Memory management functions for mlx4 driver.
 */

#include <errno.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>

/* Verbs headers do not support -pedantic. */
#ifdef PEDANTIC
#pragma GCC diagnostic ignored "-Wpedantic"
#endif
#include <infiniband/verbs.h>
#ifdef PEDANTIC
#pragma GCC diagnostic error "-Wpedantic"
#endif

#include <rte_common.h>
#include <rte_errno.h>
#include <rte_memory.h>
#include <rte_mempool.h>

#include "mlx4_utils.h"

struct mlx4_check_mempool_data {
	int ret;
	char *start;
	char *end;
};

/**
 * Called by mlx4_check_mempool() when iterating the memory chunks.
 *
 * @param[in] mp
 *   Pointer to memory pool (unused).
 * @param[in, out] data
 *   Pointer to shared buffer with mlx4_check_mempool().
 * @param[in] memhdr
 *   Pointer to mempool chunk header.
 * @param mem_idx
 *   Mempool element index (unused).
 */
static void
mlx4_check_mempool_cb(struct rte_mempool *mp, void *opaque,
		      struct rte_mempool_memhdr *memhdr,
		      unsigned int mem_idx)
{
	struct mlx4_check_mempool_data *data = opaque;

	(void)mp;
	(void)mem_idx;
	/* It already failed, skip the next chunks. */
	if (data->ret != 0)
		return;
	/* It is the first chunk. */
	if (data->start == NULL && data->end == NULL) {
		data->start = memhdr->addr;
		data->end = data->start + memhdr->len;
		return;
	}
	if (data->end == memhdr->addr) {
		data->end += memhdr->len;
		return;
	}
	if (data->start == (char *)memhdr->addr + memhdr->len) {
		data->start -= memhdr->len;
		return;
	}
	/* Error, mempool is not virtually contiguous. */
	data->ret = -1;
}

/**
 * Check if a mempool can be used: it must be virtually contiguous.
 *
 * @param[in] mp
 *   Pointer to memory pool.
 * @param[out] start
 *   Pointer to the start address of the mempool virtual memory area.
 * @param[out] end
 *   Pointer to the end address of the mempool virtual memory area.
 *
 * @return
 *   0 on success (mempool is virtually contiguous), -1 on error.
 */
static int
mlx4_check_mempool(struct rte_mempool *mp, uintptr_t *start, uintptr_t *end)
{
	struct mlx4_check_mempool_data data;

	memset(&data, 0, sizeof(data));
	rte_mempool_mem_iter(mp, mlx4_check_mempool_cb, &data);
	*start = (uintptr_t)data.start;
	*end = (uintptr_t)data.end;
	return data.ret;
}

/**
 * Register mempool as a memory region.
 *
 * @param pd
 *   Pointer to protection domain.
 * @param mp
 *   Pointer to memory pool.
 *
 * @return
 *   Memory region pointer, NULL in case of error and rte_errno is set.
 */
struct ibv_mr *
mlx4_mp2mr(struct ibv_pd *pd, struct rte_mempool *mp)
{
	const struct rte_memseg *ms = rte_eal_get_physmem_layout();
	uintptr_t start;
	uintptr_t end;
	unsigned int i;
	struct ibv_mr *mr;

	if (mlx4_check_mempool(mp, &start, &end) != 0) {
		rte_errno = EINVAL;
		ERROR("mempool %p: not virtually contiguous",
			(void *)mp);
		return NULL;
	}
	DEBUG("mempool %p area start=%p end=%p size=%zu",
	      (void *)mp, (void *)start, (void *)end,
	      (size_t)(end - start));
	/* Round start and end to page boundary if found in memory segments. */
	for (i = 0; (i < RTE_MAX_MEMSEG) && (ms[i].addr != NULL); ++i) {
		uintptr_t addr = (uintptr_t)ms[i].addr;
		size_t len = ms[i].len;
		unsigned int align = ms[i].hugepage_sz;

		if ((start > addr) && (start < addr + len))
			start = RTE_ALIGN_FLOOR(start, align);
		if ((end > addr) && (end < addr + len))
			end = RTE_ALIGN_CEIL(end, align);
	}
	DEBUG("mempool %p using start=%p end=%p size=%zu for MR",
	      (void *)mp, (void *)start, (void *)end,
	      (size_t)(end - start));
	mr = ibv_reg_mr(pd,
			(void *)start,
			end - start,
			IBV_ACCESS_LOCAL_WRITE);
	if (!mr)
		rte_errno = errno ? errno : EINVAL;
	return mr;
}