/* * vhost software live migration iova tree * * SPDX-FileCopyrightText: Red Hat, Inc. 2021 * SPDX-FileContributor: Author: Eugenio PĂ©rez <eperezma@redhat.com> * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "qemu/osdep.h" #include "qemu/iova-tree.h" #include "vhost-iova-tree.h" #define iova_min_addr qemu_real_host_page_size() /** * VhostIOVATree, able to: * - Translate iova address * - Reverse translate iova address (from translated to iova) * - Allocate IOVA regions for translated range (linear operation) */ struct VhostIOVATree { /* First addressable iova address in the device */ uint64_t iova_first; /* Last addressable iova address in the device */ uint64_t iova_last; /* IOVA address to qemu memory maps. */ IOVATree *iova_taddr_map; }; /** * Create a new IOVA tree * * Returns the new IOVA tree */ VhostIOVATree *vhost_iova_tree_new(hwaddr iova_first, hwaddr iova_last) { VhostIOVATree *tree = g_new(VhostIOVATree, 1); /* Some devices do not like 0 addresses */ tree->iova_first = MAX(iova_first, iova_min_addr); tree->iova_last = iova_last; tree->iova_taddr_map = iova_tree_new(); return tree; } /** * Delete an iova tree */ void vhost_iova_tree_delete(VhostIOVATree *iova_tree) { iova_tree_destroy(iova_tree->iova_taddr_map); g_free(iova_tree); } /** * Find the IOVA address stored from a memory address * * @tree: The iova tree * @map: The map with the memory address * * Return the stored mapping, or NULL if not found. */ const DMAMap *vhost_iova_tree_find_iova(const VhostIOVATree *tree, const DMAMap *map) { return iova_tree_find_iova(tree->iova_taddr_map, map); } /** * Allocate a new mapping * * @tree: The iova tree * @map: The iova map * * Returns: * - IOVA_OK if the map fits in the container * - IOVA_ERR_INVALID if the map does not make sense (like size overflow) * - IOVA_ERR_NOMEM if tree cannot allocate more space. * * It returns assignated iova in map->iova if return value is VHOST_DMA_MAP_OK. */ int vhost_iova_tree_map_alloc(VhostIOVATree *tree, DMAMap *map) { /* Some vhost devices do not like addr 0. Skip first page */ hwaddr iova_first = tree->iova_first ?: qemu_real_host_page_size(); if (map->translated_addr + map->size < map->translated_addr || map->perm == IOMMU_NONE) { return IOVA_ERR_INVALID; } /* Allocate a node in IOVA address */ return iova_tree_alloc_map(tree->iova_taddr_map, map, iova_first, tree->iova_last); } /** * Remove existing mappings from iova tree * * @iova_tree: The vhost iova tree * @map: The map to remove */ void vhost_iova_tree_remove(VhostIOVATree *iova_tree, DMAMap map) { iova_tree_remove(iova_tree->iova_taddr_map, map); }