From patchwork Mon Mar 24 13:53:02 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bertrand Marquis X-Patchwork-Id: 14027397 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0382FC36002 for ; Mon, 24 Mar 2025 13:53:37 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.925585.1328489 (Exim 4.92) (envelope-from ) id 1twiF8-0000sy-5w; Mon, 24 Mar 2025 13:53:30 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 925585.1328489; Mon, 24 Mar 2025 13:53:30 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1twiF8-0000sk-2s; Mon, 24 Mar 2025 13:53:30 +0000 Received: by outflank-mailman (input) for mailman id 925585; Mon, 24 Mar 2025 13:53:28 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1twiF6-0008HJ-MR for xen-devel@lists.xenproject.org; Mon, 24 Mar 2025 13:53:28 +0000 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by se1-gles-sth1.inumbo.com (Halon) with ESMTP id 5cdf23f1-08b7-11f0-9ea2-5ba50f476ded; Mon, 24 Mar 2025 14:53:28 +0100 (CET) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B9A501C14; Mon, 24 Mar 2025 06:53:33 -0700 (PDT) Received: from C3HXLD123V.arm.com (unknown [10.57.86.79]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0B2FC3F58B; Mon, 24 Mar 2025 06:53:25 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 5cdf23f1-08b7-11f0-9ea2-5ba50f476ded From: Bertrand Marquis To: xen-devel@lists.xenproject.org Cc: jens.wiklander@linaro.org, Volodymyr Babchuk , Stefano Stabellini , Julien Grall , Michal Orzel Subject: [PATCH v4 4/5] xen/arm: ffa: Add indirect message between VM Date: Mon, 24 Mar 2025 14:53:02 +0100 Message-ID: <719dad25719a0834dc0e52da715aca989a3c20fb.1742824138.git.bertrand.marquis@arm.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: References: MIME-Version: 1.0 Add support for indirect messages between VMs. This is only enabled if CONFIG_FFA_VM_TO_VM is selected. Signed-off-by: Bertrand Marquis Reviewed-by: Jens Wiklander --- Changes in v4: - Use a local copy of the message header to prevent a TOC/TOU possible issue when using the payload size Changes in v3: - Move vm to vm indirect message handling in a sub function to simplify lock handling and make implementation easier to read Changes in v2: - Switch ifdef to IS_ENABLED --- xen/arch/arm/tee/ffa_msg.c | 110 ++++++++++++++++++++++++++++++++----- 1 file changed, 96 insertions(+), 14 deletions(-) diff --git a/xen/arch/arm/tee/ffa_msg.c b/xen/arch/arm/tee/ffa_msg.c index ee594e737fc7..7c36e3aac47c 100644 --- a/xen/arch/arm/tee/ffa_msg.c +++ b/xen/arch/arm/tee/ffa_msg.c @@ -88,43 +88,125 @@ out: resp.a7 & mask); } +static int32_t ffa_msg_send2_vm(uint16_t dst_id, + struct ffa_part_msg_rxtx *src_msg) +{ + struct domain *dst_d; + struct ffa_ctx *dst_ctx; + struct ffa_part_msg_rxtx *dst_msg; + int err; + int32_t ret; + + if ( dst_id == 0 ) + /* FF-A ID 0 is the hypervisor, this is not valid */ + return FFA_RET_INVALID_PARAMETERS; + + /* This is also checking that dest is not src */ + err = rcu_lock_live_remote_domain_by_id(dst_id - 1, &dst_d); + if ( err ) + return FFA_RET_INVALID_PARAMETERS; + + if ( dst_d->arch.tee == NULL ) + { + ret = FFA_RET_INVALID_PARAMETERS; + goto out_unlock; + } + + dst_ctx = dst_d->arch.tee; + if ( !dst_ctx->guest_vers ) + { + ret = FFA_RET_INVALID_PARAMETERS; + goto out_unlock; + } + + /* we need to have enough space in the destination buffer */ + if ( dst_ctx->page_count * FFA_PAGE_SIZE < + (sizeof(struct ffa_part_msg_rxtx) + src_msg->msg_size) ) + { + ret = FFA_RET_NO_MEMORY; + goto out_unlock; + } + + /* This also checks that destination has set a Rx buffer */ + ret = ffa_rx_acquire(dst_d); + if ( ret ) + goto out_unlock; + + dst_msg = dst_ctx->rx; + + /* prepare destination header */ + dst_msg->flags = 0; + dst_msg->reserved = 0; + dst_msg->msg_offset = sizeof(struct ffa_part_msg_rxtx); + dst_msg->send_recv_id = src_msg->send_recv_id; + dst_msg->msg_size = src_msg->msg_size; + + memcpy(dst_ctx->rx + sizeof(struct ffa_part_msg_rxtx), + ((void *)src_msg) + src_msg->msg_offset, src_msg->msg_size); + + /* receiver rx buffer will be released by the receiver*/ + +out_unlock: + rcu_unlock_domain(dst_d); + if ( !ret ) + ffa_raise_rx_buffer_full(dst_d); + + return ret; +} + int32_t ffa_handle_msg_send2(struct cpu_user_regs *regs) { struct domain *src_d = current->domain; struct ffa_ctx *src_ctx = src_d->arch.tee; - const struct ffa_part_msg_rxtx *src_msg; + struct ffa_part_msg_rxtx src_msg; uint16_t dst_id, src_id; int32_t ret; - if ( !ffa_fw_supports_fid(FFA_MSG_SEND2) ) - return FFA_RET_NOT_SUPPORTED; - if ( !spin_trylock(&src_ctx->tx_lock) ) return FFA_RET_BUSY; - src_msg = src_ctx->tx; - src_id = src_msg->send_recv_id >> 16; - dst_id = src_msg->send_recv_id & GENMASK(15,0); + /* create a copy of the message header */ + memcpy(&src_msg, src_ctx->tx, sizeof(src_msg)); + + src_id = src_msg.send_recv_id >> 16; + dst_id = src_msg.send_recv_id & GENMASK(15,0); - if ( src_id != ffa_get_vm_id(src_d) || !FFA_ID_IS_SECURE(dst_id) ) + if ( src_id != ffa_get_vm_id(src_d) ) { ret = FFA_RET_INVALID_PARAMETERS; - goto out_unlock_tx; + goto out; } /* check source message fits in buffer */ if ( src_ctx->page_count * FFA_PAGE_SIZE < - src_msg->msg_offset + src_msg->msg_size || - src_msg->msg_offset < sizeof(struct ffa_part_msg_rxtx) ) + src_msg.msg_offset + src_msg.msg_size || + src_msg.msg_offset < sizeof(struct ffa_part_msg_rxtx) ) { ret = FFA_RET_INVALID_PARAMETERS; - goto out_unlock_tx; + goto out; } - ret = ffa_simple_call(FFA_MSG_SEND2, + if ( FFA_ID_IS_SECURE(dst_id) ) + { + /* Message for a secure partition */ + if ( !ffa_fw_supports_fid(FFA_MSG_SEND2) ) + { + ret = FFA_RET_NOT_SUPPORTED; + goto out; + } + + ret = ffa_simple_call(FFA_MSG_SEND2, ((uint32_t)ffa_get_vm_id(src_d)) << 16, 0, 0, 0); + } + else if ( IS_ENABLED(CONFIG_FFA_VM_TO_VM) ) + { + /* Message for a VM */ + ret = ffa_msg_send2_vm(dst_id, &src_msg); + } + else + ret = FFA_RET_INVALID_PARAMETERS; -out_unlock_tx: +out: spin_unlock(&src_ctx->tx_lock); return ret; }