From patchwork Sat Apr 22 13:03:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Weiwei Li X-Patchwork-Id: 13220995 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.gnu.org (lists.gnu.org [209.51.188.17]) (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 B3562C7618E for ; Sat, 22 Apr 2023 13:06:12 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pqCuq-0007vU-7v; Sat, 22 Apr 2023 09:04:36 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pqCuh-0007nE-Sc; Sat, 22 Apr 2023 09:04:27 -0400 Received: from smtp80.cstnet.cn ([159.226.251.80] helo=cstnet.cn) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pqCud-0004Un-LB; Sat, 22 Apr 2023 09:04:27 -0400 Received: from localhost.localdomain (unknown [180.165.241.15]) by APP-01 (Coremail) with SMTP id qwCowAAHTJxI20NkLKGxCA--.21573S3; Sat, 22 Apr 2023 21:04:10 +0800 (CST) From: Weiwei Li To: qemu-riscv@nongnu.org, qemu-devel@nongnu.org Cc: palmer@dabbelt.com, alistair.francis@wdc.com, bin.meng@windriver.com, dbarboza@ventanamicro.com, zhiwei_liu@linux.alibaba.com, richard.henderson@linaro.org, wangjunqiang@iscas.ac.cn, lazyparser@gmail.com, Weiwei Li Subject: [PATCH v4 1/7] target/riscv: Update pmp_get_tlb_size() Date: Sat, 22 Apr 2023 21:03:23 +0800 Message-Id: <20230422130329.23555-2-liweiwei@iscas.ac.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230422130329.23555-1-liweiwei@iscas.ac.cn> References: <20230422130329.23555-1-liweiwei@iscas.ac.cn> MIME-Version: 1.0 X-CM-TRANSID: qwCowAAHTJxI20NkLKGxCA--.21573S3 X-Coremail-Antispam: 1UD129KBjvJXoWxtrW7Aw4UJw43KrWfKry5CFg_yoW7Ar4rpr WxCrW7GrZ7K39xJ3W3JF4DXF15Aw4fKr4UCa97WFZYka15G3yrAr1qkrWa9ry8GayDurWY 9FWqyFn8CF4UXaUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBE14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2 xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMI IF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JU2_M3UUUUU = X-Originating-IP: [180.165.241.15] X-CM-SenderInfo: 5olzvxxzhlqxpvfd2hldfou0/ Received-SPF: pass client-ip=159.226.251.80; envelope-from=liweiwei@iscas.ac.cn; helo=cstnet.cn X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org PMP entries before the matched PMP entry (including the matched PMP entry) may only cover partial of the TLB page, which may make different regions in that page allow different RWX privs, such as for PMP0 (0x80000008~0x8000000F, R) and PMP1 (0x80001000~0x80001FFF, RWX) write access to 0x80000000 will match PMP1. However we cannot cache the translation result in the TLB since this will make the write access to 0x80000008 bypass the check of PMP0. So we should check all of them instead of the matched PMP entry in pmp_get_tlb_size() and set the tlb_size to 1 in this case. Set tlb_size to TARGET_PAGE_SIZE if PMP is not support or there is no PMP rules. Signed-off-by: Weiwei Li Signed-off-by: Junqiang Wang Reviewed-by: LIU Zhiwei --- target/riscv/cpu_helper.c | 7 ++--- target/riscv/pmp.c | 64 ++++++++++++++++++++++++++++++--------- target/riscv/pmp.h | 3 +- 3 files changed, 52 insertions(+), 22 deletions(-) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 433ea529b0..075fc0538a 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -703,11 +703,8 @@ static int get_physical_address_pmp(CPURISCVState *env, int *prot, } *prot = pmp_priv_to_page_prot(pmp_priv); - if ((tlb_size != NULL) && pmp_index != MAX_RISCV_PMPS) { - target_ulong tlb_sa = addr & ~(TARGET_PAGE_SIZE - 1); - target_ulong tlb_ea = tlb_sa + TARGET_PAGE_SIZE - 1; - - *tlb_size = pmp_get_tlb_size(env, pmp_index, tlb_sa, tlb_ea); + if (tlb_size != NULL) { + *tlb_size = pmp_get_tlb_size(env, addr); } return TRANSLATE_SUCCESS; diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c index 1f5aca42e8..ad20a319c1 100644 --- a/target/riscv/pmp.c +++ b/target/riscv/pmp.c @@ -601,28 +601,62 @@ target_ulong mseccfg_csr_read(CPURISCVState *env) } /* - * Calculate the TLB size if the start address or the end address of - * PMP entry is presented in the TLB page. + * Calculate the TLB size. If the PMP rules may make different regions in + * the TLB page of 'addr' allow different RWX privs, set the size to 1 + * (to make the translation result uncached in the TLB and only be used for + * a single translation). Set the size to TARGET_PAGE_SIZE otherwise. */ -target_ulong pmp_get_tlb_size(CPURISCVState *env, int pmp_index, - target_ulong tlb_sa, target_ulong tlb_ea) +target_ulong pmp_get_tlb_size(CPURISCVState *env, target_ulong addr) { - target_ulong pmp_sa = env->pmp_state.addr[pmp_index].sa; - target_ulong pmp_ea = env->pmp_state.addr[pmp_index].ea; + target_ulong pmp_sa; + target_ulong pmp_ea; + target_ulong tlb_sa = addr & ~(TARGET_PAGE_SIZE - 1); + target_ulong tlb_ea = tlb_sa + TARGET_PAGE_SIZE - 1; + int i; - if (pmp_sa <= tlb_sa && pmp_ea >= tlb_ea) { + /* + * If PMP is not supported or there is no PMP rule, which means the allowed + * RWX privs of the page will not affected by PMP or PMP will provide the + * same option (disallow accesses or allow default RWX privs) for all + * addresses, set the size to TARGET_PAGE_SIZE. + */ + if (!riscv_cpu_cfg(env)->pmp || !pmp_get_num_rules(env)) { return TARGET_PAGE_SIZE; - } else { + } + + for (i = 0; i < MAX_RISCV_PMPS; i++) { + if (pmp_get_a_field(env->pmp_state.pmp[i].cfg_reg) == PMP_AMATCH_OFF) { + continue; + } + + pmp_sa = env->pmp_state.addr[i].sa; + pmp_ea = env->pmp_state.addr[i].ea; + /* - * At this point we have a tlb_size that is the smallest possible size - * That fits within a TARGET_PAGE_SIZE and the PMP region. - * - * If the size is less then TARGET_PAGE_SIZE we drop the size to 1. - * This means the result isn't cached in the TLB and is only used for - * a single translation. + * Only the first PMP entry that covers (whole or partial of) the TLB + * page really matters: + * If it can cover the whole page, set the size to TARGET_PAGE_SIZE. + * The following PMP entries have lower priority and will not affect + * the allowed RWX privs of the page. + * If it only cover partial of the TLB page, set the size to 1 since + * the allowed RWX privs for the covered region may be different from + * other region of the page. */ - return 1; + if (pmp_sa <= tlb_sa && pmp_ea >= tlb_ea) { + return TARGET_PAGE_SIZE; + } else if ((pmp_sa >= tlb_sa && pmp_sa <= tlb_ea) || + (pmp_ea >= tlb_sa && pmp_ea <= tlb_ea)) { + return 1; + } } + + /* + * If no PMP entry covers any region of the TLB page, similar to the above + * case that there is no PMP rule, PMP will provide the same option + * (disallow accesses or allow default RWX privs) for the whole page, + * set the size to TARGET_PAGE_SIZE. + */ + return TARGET_PAGE_SIZE; } /* diff --git a/target/riscv/pmp.h b/target/riscv/pmp.h index b296ea1fc6..0a7e24750b 100644 --- a/target/riscv/pmp.h +++ b/target/riscv/pmp.h @@ -76,8 +76,7 @@ int pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, target_ulong size, pmp_priv_t privs, pmp_priv_t *allowed_privs, target_ulong mode); -target_ulong pmp_get_tlb_size(CPURISCVState *env, int pmp_index, - target_ulong tlb_sa, target_ulong tlb_ea); +target_ulong pmp_get_tlb_size(CPURISCVState *env, target_ulong addr); void pmp_update_rule_addr(CPURISCVState *env, uint32_t pmp_index); void pmp_update_rule_nums(CPURISCVState *env); uint32_t pmp_get_num_rules(CPURISCVState *env);