From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84B55CD4F39 for ; Fri, 15 May 2026 01:04:42 +0000 (UTC) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 9049640274; Fri, 15 May 2026 03:04:41 +0200 (CEST) Received: from canpmsgout03.his.huawei.com (canpmsgout03.his.huawei.com [113.46.200.218]) by mails.dpdk.org (Postfix) with ESMTP id 47CE540151 for ; Fri, 15 May 2026 03:04:40 +0200 (CEST) dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=jwTm2xVUnXpSISi+h+/zmM96OlXuoi2ph4xwwyAwNtc=; b=dX7sj5QyDitSwVeIVUDLhqP7RVYUmhJSkPzfELgfGVwB7Z73bD0YU/HOw1V2dAXPi22YcIe89 OUH0ZzhxuEE1mZhvyoktBOMod/OzZmmnWgWj4JTwZDSd3tPug0V08bKKo6WYxDSKmpfCatg3TGJ 3D52q3mS5YZ0HmdD/qjMqiE= Received: from mail.maildlp.com (unknown [172.19.163.104]) by canpmsgout03.his.huawei.com (SkyGuard) with ESMTPS id 4gGphF2VXtzpTHf; Fri, 15 May 2026 08:57:33 +0800 (CST) Received: from kwepemk500009.china.huawei.com (unknown [7.202.194.94]) by mail.maildlp.com (Postfix) with ESMTPS id ADEEE4048F; Fri, 15 May 2026 09:04:37 +0800 (CST) Received: from [10.67.121.161] (10.67.121.161) by kwepemk500009.china.huawei.com (7.202.194.94) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 15 May 2026 09:04:37 +0800 Message-ID: <71c3a27c-a76f-4339-a4f5-997cd1d98286@huawei.com> Date: Fri, 15 May 2026 09:04:36 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v13 4/5] vhost_user: Function defs for add/rem mem regions To: , , , CC: References: <20260514224627.2014566-1-pravin.bathija@dell.com> <20260514224627.2014566-5-pravin.bathija@dell.com> Content-Language: en-US From: fengchengwen In-Reply-To: <20260514224627.2014566-5-pravin.bathija@dell.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.121.161] X-ClientProxiedBy: kwepems100002.china.huawei.com (7.221.188.206) To kwepemk500009.china.huawei.com (7.202.194.94) X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On 5/15/2026 6:46 AM, pravin.bathija@dell.com wrote: > From: Pravin M Bathija > > These changes cover the function definition for add/remove memory > region calls which are invoked on receiving vhost user message from > vhost user front-end (e.g. Qemu). In our case, in addition to testing > with qemu front-end, the testing has also been performed with libblkio > front-end and spdk/dpdk back-end. We did I/O using libblkio based device > driver, to spdk based drives. > There are also changes for set_mem_table and new definition for get memory > slots. Our changes optimize the set memory table call to use common support > functions. A new vhost_user_initialize_memory() function is introduced to > factor out the common memory initialization logic from the function > vhost_user_set_mem_table(), which is now called from both the SET_MEM_TABLE > message handler and the ADD_MEM_REG handler (for the first region). > Message get memory slots is how the vhost-user front-end queries the > vhost-user back-end about the number of memory slots available to be > registered by the back-end. In addition support function to invalidate > vring is also defined which is used in add/remove memory region functions. > The helper function remove_guest_pages is also defined here which is called > from vhost_user_add_mem_reg. Two much detail which provide noisy infomation I think, how about: vhost: add mem region add/remove handlers Add support for VHOST_USER_ADD_MEM_REG, VHOST_USER_REM_MEM_REG and VHOST_USER_GET_MAX_MEM_SLOTS. Refactor memory initialization into common helper and add supporting functions for dynamic memory management. Signed-off-by: Pravin M Bathija > > Signed-off-by: Pravin M Bathija > --- > lib/vhost/vhost_user.c | 329 ++++++++++++++++++++++++++++++++++++----- > 1 file changed, 296 insertions(+), 33 deletions(-) > > diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c > index 0ee3fe7a5e..fdcb7e0158 100644 > --- a/lib/vhost/vhost_user.c > +++ b/lib/vhost/vhost_user.c > @@ -71,6 +71,9 @@ VHOST_MESSAGE_HANDLER(VHOST_USER_SET_FEATURES, vhost_user_set_features, false, t > VHOST_MESSAGE_HANDLER(VHOST_USER_SET_OWNER, vhost_user_set_owner, false, true) \ > VHOST_MESSAGE_HANDLER(VHOST_USER_RESET_OWNER, vhost_user_reset_owner, false, false) \ > VHOST_MESSAGE_HANDLER(VHOST_USER_SET_MEM_TABLE, vhost_user_set_mem_table, true, true) \ > +VHOST_MESSAGE_HANDLER(VHOST_USER_GET_MAX_MEM_SLOTS, vhost_user_get_max_mem_slots, false, false) \ > +VHOST_MESSAGE_HANDLER(VHOST_USER_ADD_MEM_REG, vhost_user_add_mem_reg, true, true) \ > +VHOST_MESSAGE_HANDLER(VHOST_USER_REM_MEM_REG, vhost_user_rem_mem_reg, true, true) \ > VHOST_MESSAGE_HANDLER(VHOST_USER_SET_LOG_BASE, vhost_user_set_log_base, true, true) \ > VHOST_MESSAGE_HANDLER(VHOST_USER_SET_LOG_FD, vhost_user_set_log_fd, true, true) \ > VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_NUM, vhost_user_set_vring_num, false, true) \ > @@ -1167,6 +1170,24 @@ add_guest_pages(struct virtio_net *dev, struct rte_vhost_mem_region *reg, > return 0; > } > > +static void > +remove_guest_pages(struct virtio_net *dev, struct rte_vhost_mem_region *reg) > +{ > + uint64_t reg_start = reg->host_user_addr; > + uint64_t reg_end = reg_start + reg->size; > + uint32_t i, j = 0; > + > + for (i = 0; i < dev->nr_guest_pages; i++) { > + if (dev->guest_pages[i].host_user_addr >= reg_start && > + dev->guest_pages[i].host_user_addr < reg_end) > + continue; > + if (j != i) > + dev->guest_pages[j] = dev->guest_pages[i]; > + j++; > + } > + dev->nr_guest_pages = j; > +} > + > #ifdef RTE_LIBRTE_VHOST_DEBUG > /* TODO: enable it only in debug mode? */ > static void > @@ -1413,6 +1434,52 @@ vhost_user_mmap_region(struct virtio_net *dev, > return 0; > } > > +static int > +vhost_user_initialize_memory(struct virtio_net **pdev) > +{ > + struct virtio_net *dev = *pdev; > + int numa_node = SOCKET_ID_ANY; > + > + if (dev->mem != NULL) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, > + "memory already initialized, free it first"); > + return -1; > + } > + > + /* > + * If VQ 0 has already been allocated, try to allocate on the same > + * NUMA node. It can be reallocated later in numa_realloc(). > + */ > + if (dev->nr_vring > 0) > + numa_node = dev->virtqueue[0]->numa_node; > + > + dev->nr_guest_pages = 0; > + if (dev->guest_pages == NULL) { > + dev->max_guest_pages = 8; > + dev->guest_pages = rte_zmalloc_socket(NULL, > + dev->max_guest_pages * > + sizeof(struct guest_page), > + RTE_CACHE_LINE_SIZE, > + numa_node); > + if (dev->guest_pages == NULL) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, > + "failed to allocate memory for dev->guest_pages"); > + return -1; > + } > + } > + > + dev->mem = rte_zmalloc_socket("vhost-mem-table", sizeof(struct rte_vhost_memory) + > + sizeof(struct rte_vhost_mem_region) * VHOST_MEMORY_MAX_NREGIONS, 0, numa_node); > + if (dev->mem == NULL) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, "failed to allocate memory for dev->mem"); > + rte_free(dev->guest_pages); > + dev->guest_pages = NULL; > + return -1; > + } > + > + return 0; > +} > + > static int > vhost_user_set_mem_table(struct virtio_net **pdev, > struct vhu_msg_context *ctx, > @@ -1421,7 +1488,6 @@ vhost_user_set_mem_table(struct virtio_net **pdev, > struct virtio_net *dev = *pdev; > struct VhostUserMemory *memory = &ctx->msg.payload.memory; > struct rte_vhost_mem_region *reg; > - int numa_node = SOCKET_ID_ANY; > uint64_t mmap_offset; > uint32_t i; > bool async_notify = false; > @@ -1466,39 +1532,13 @@ vhost_user_set_mem_table(struct virtio_net **pdev, > if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)) > vhost_user_iotlb_flush_all(dev); > > - free_mem_region(dev); > + free_all_mem_regions(dev); This should be done in commit 3/5, I suspect that 3/5 of the code may fail to be compiled. Please make sure each commit should compile OK, so that git commit binary search and troubleshooting could work. > rte_free(dev->mem); > dev->mem = NULL; > } > > - /* > - * If VQ 0 has already been allocated, try to allocate on the same > - * NUMA node. It can be reallocated later in numa_realloc(). > - */ > - if (dev->nr_vring > 0) > - numa_node = dev->virtqueue[0]->numa_node; > - > - dev->nr_guest_pages = 0; > - if (dev->guest_pages == NULL) { > - dev->max_guest_pages = 8; > - dev->guest_pages = rte_zmalloc_socket(NULL, > - dev->max_guest_pages * > - sizeof(struct guest_page), > - RTE_CACHE_LINE_SIZE, > - numa_node); > - if (dev->guest_pages == NULL) { > - VHOST_CONFIG_LOG(dev->ifname, ERR, > - "failed to allocate memory for dev->guest_pages"); > - goto close_msg_fds; > - } > - } > - > - dev->mem = rte_zmalloc_socket("vhost-mem-table", sizeof(struct rte_vhost_memory) + > - sizeof(struct rte_vhost_mem_region) * memory->nregions, 0, numa_node); > - if (dev->mem == NULL) { > - VHOST_CONFIG_LOG(dev->ifname, ERR, "failed to allocate memory for dev->mem"); > - goto free_guest_pages; > - } > + if (vhost_user_initialize_memory(pdev) < 0) > + goto close_msg_fds; > > for (i = 0; i < memory->nregions; i++) { > reg = &dev->mem->regions[i]; > @@ -1562,11 +1602,9 @@ vhost_user_set_mem_table(struct virtio_net **pdev, > return RTE_VHOST_MSG_RESULT_OK; > > free_mem_table: > - free_mem_region(dev); > + free_all_mem_regions(dev); Same, it should be done in commit 3/5 > rte_free(dev->mem); > dev->mem = NULL; > - > -free_guest_pages: > rte_free(dev->guest_pages); > dev->guest_pages = NULL; > close_msg_fds: > @@ -1574,6 +1612,231 @@ vhost_user_set_mem_table(struct virtio_net **pdev, > return RTE_VHOST_MSG_RESULT_ERR; > } > > + > +static int > +vhost_user_get_max_mem_slots(struct virtio_net **pdev __rte_unused, > + struct vhu_msg_context *ctx, > + int main_fd __rte_unused) > +{ > + uint32_t max_mem_slots = VHOST_MEMORY_MAX_NREGIONS; > + > + ctx->msg.payload.u64 = (uint64_t)max_mem_slots; > + ctx->msg.size = sizeof(ctx->msg.payload.u64); > + ctx->fd_num = 0; > + > + return RTE_VHOST_MSG_RESULT_REPLY; > +} > + > +static void > +_dev_invalidate_vrings(struct virtio_net **pdev) It seems that there is no such naming convention in vhost. > +{ > + struct virtio_net *dev = *pdev; > + uint32_t i; > + > + for (i = 0; i < dev->nr_vring; i++) { > + struct vhost_virtqueue *vq = dev->virtqueue[i]; > + > + if (!vq) > + continue; > + > + if (vq->desc || vq->avail || vq->used) { > + vq_assert_lock(dev, vq); > + > + /* > + * If the memory table got updated, the ring addresses > + * need to be translated again as virtual addresses have > + * changed. > + */ > + vring_invalidate(dev, vq); > + > + translate_ring_addresses(&dev, &vq); > + } > + } > + > + *pdev = dev; why do this? > +} > + > +/* > + * Macro wrapper that performs the compile-time lock assertion with the > + * correct message ID at the call site, then calls the implementation. > + */ > +#define dev_invalidate_vrings(pdev, id) do { \ > + static_assert(id ## _LOCK_ALL_QPS, \ > + #id " handler is not declared as locking all queue pairs"); \ > + _dev_invalidate_vrings(pdev); \ > +} while (0) > + > +static int > +vhost_user_add_mem_reg(struct virtio_net **pdev, > + struct vhu_msg_context *ctx, > + int main_fd __rte_unused) > +{ > + uint32_t i; > + struct virtio_net *dev = *pdev; > + struct VhostUserMemoryRegion *region = &ctx->msg.payload.memreg.region; Local variables should be arranged in descending order of length. struct VhostUserMemoryRegion *region = &ctx->msg.payload.memreg.region; struct virtio_net *dev = *pdev; uint32_t i; > + > + /* convert first region add to normal memory table set */ > + if (dev->mem == NULL) { > + if (vhost_user_initialize_memory(pdev) < 0) > + goto close_msg_fds; > + } > + > + /* make sure new region will fit */ > + if (dev->mem->nregions >= VHOST_MEMORY_MAX_NREGIONS) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, "too many memory regions already (%u)", > + dev->mem->nregions); > + goto close_msg_fds; > + } > + > + /* make sure supplied memory fd present */ > + if (ctx->fd_num != 1) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, "fd count makes no sense (%u)", ctx->fd_num); > + goto close_msg_fds; > + } > + > + /* Make sure no overlap in guest virtual address space */ > + for (i = 0; i < dev->mem->nregions; i++) { > + struct rte_vhost_mem_region *current_region = &dev->mem->regions[i]; > + uint64_t current_region_guest_start = current_region->guest_user_addr; > + uint64_t current_region_guest_end = current_region_guest_start > + + current_region->size - 1; > + uint64_t proposed_region_guest_start = region->userspace_addr; > + uint64_t proposed_region_guest_end = proposed_region_guest_start > + + region->memory_size - 1; why not use short name? > + > + if (!((proposed_region_guest_end < current_region_guest_start) || > + (proposed_region_guest_start > current_region_guest_end))) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, > + "requested memory region overlaps with another region"); > + VHOST_CONFIG_LOG(dev->ifname, ERR, > + "\tRequested region address:0x%" PRIx64, > + region->userspace_addr); > + VHOST_CONFIG_LOG(dev->ifname, ERR, > + "\tRequested region size:0x%" PRIx64, > + region->memory_size); > + VHOST_CONFIG_LOG(dev->ifname, ERR, > + "\tOverlapping region address:0x%" PRIx64, > + current_region->guest_user_addr); > + VHOST_CONFIG_LOG(dev->ifname, ERR, > + "\tOverlapping region size:0x%" PRIx64, > + current_region->size); > + goto close_msg_fds; > + } > + } > + > + /* New region goes at the end of the contiguous array */ > + struct rte_vhost_mem_region *reg = &dev->mem->regions[dev->mem->nregions]; > + > + reg->guest_phys_addr = region->guest_phys_addr; > + reg->guest_user_addr = region->userspace_addr; > + reg->size = region->memory_size; > + reg->fd = ctx->fds[0]; > + ctx->fds[0] = -1; > + > + if (vhost_user_mmap_region(dev, reg, region->mmap_offset) < 0) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, "failed to mmap region"); > + if (reg->mmap_addr) { > + /* mmap succeeded but a later step (e.g. add_guest_pages) > + * failed; undo the mapping and any guest-page entries. > + */ > + remove_guest_pages(dev, reg); > + free_mem_region(reg); > + } else { > + close(reg->fd); > + reg->fd = -1; > + } > + goto close_msg_fds; > + } > + > + dev->mem->nregions++; > + > + if (dev->async_copy && rte_vfio_is_enabled("vfio")) { > + if (async_dma_map_region(dev, reg, true) < 0) > + goto free_new_region; I point it out in v12, maybe not so clear, so again: the goto will invoke async_dma_map_region(dev, reg, false), it should not invoke in this branch. > + } > + > + if (dev->postcopy_listening) { > + /* > + * Cannot use vhost_user_postcopy_register() here because it > + * reads ctx->msg.payload.memory (SET_MEM_TABLE layout), but > + * ADD_MEM_REG uses the memreg payload. Register the > + * single new region directly instead. > + */ > + if (vhost_user_postcopy_region_register(dev, reg) < 0) > + goto free_new_region; > + } > + > + dev_invalidate_vrings(pdev, VHOST_USER_ADD_MEM_REG); > + dev = *pdev; What the meaning? the dev already set *pdev in the beginning. I also point it out in v12, I don't know what happening. > + dump_guest_pages(dev); > + > + return RTE_VHOST_MSG_RESULT_OK; > + > +free_new_region: > + if (dev->async_copy && rte_vfio_is_enabled("vfio")) > + async_dma_map_region(dev, reg, false); > + remove_guest_pages(dev, reg); > + free_mem_region(reg); > + dev->mem->nregions--; > +close_msg_fds: > + close_msg_fds(ctx); > + return RTE_VHOST_MSG_RESULT_ERR; > +} > + > +static int > +vhost_user_rem_mem_reg(struct virtio_net **pdev, > + struct vhu_msg_context *ctx, > + int main_fd __rte_unused) > +{ > + uint32_t i; > + struct virtio_net *dev = *pdev; > + struct VhostUserMemoryRegion *region = &ctx->msg.payload.memreg.region; > + > + if (dev->mem == NULL || dev->mem->nregions == 0) { > + VHOST_CONFIG_LOG(dev->ifname, ERR, "no memory regions to remove"); > + close_msg_fds(ctx); > + return RTE_VHOST_MSG_RESULT_ERR; > + } > + > + for (i = 0; i < dev->mem->nregions; i++) { > + struct rte_vhost_mem_region *current_region = &dev->mem->regions[i]; > + > + /* > + * According to the vhost-user specification: > + * The memory region to be removed is identified by its GPA, > + * user address and size. The mmap offset is ignored. > + */ > + if (region->userspace_addr == current_region->guest_user_addr > + && region->guest_phys_addr == current_region->guest_phys_addr > + && region->memory_size == current_region->size) { > + if (dev->async_copy && rte_vfio_is_enabled("vfio")) > + async_dma_map_region(dev, current_region, false); > + remove_guest_pages(dev, current_region); > + free_mem_region(current_region); > + > + /* Compact the regions array to keep it contiguous */ > + if (i < dev->mem->nregions - 1) { > + memmove(&dev->mem->regions[i], > + &dev->mem->regions[i + 1], > + (dev->mem->nregions - 1 - i) * > + sizeof(struct rte_vhost_mem_region)); > + memset(&dev->mem->regions[dev->mem->nregions - 1], > + 0, sizeof(struct rte_vhost_mem_region)); > + } > + > + dev->mem->nregions--; > + dev_invalidate_vrings(pdev, VHOST_USER_REM_MEM_REG); > + dev = *pdev; I still don't know what the assignment meaning/function? > + close_msg_fds(ctx); > + return RTE_VHOST_MSG_RESULT_OK; > + } > + } > + > + VHOST_CONFIG_LOG(dev->ifname, ERR, "failed to find region"); > + close_msg_fds(ctx); > + return RTE_VHOST_MSG_RESULT_ERR; > +} > + > static bool > vq_is_ready(struct virtio_net *dev, struct vhost_virtqueue *vq) > {