From patchwork Wed Sep 26 18:02:33 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stephen Boyd X-Patchwork-Id: 10616491 X-Patchwork-Delegate: agross@codeaurora.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5DDEB112B for ; Wed, 26 Sep 2018 18:03:35 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4F1CB28EA1 for ; Wed, 26 Sep 2018 18:03:35 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 427EC2B5F2; Wed, 26 Sep 2018 18:03:35 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A462328EA1 for ; Wed, 26 Sep 2018 18:03:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726107AbeI0ARk (ORCPT ); Wed, 26 Sep 2018 20:17:40 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:46305 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726230AbeI0ARk (ORCPT ); Wed, 26 Sep 2018 20:17:40 -0400 Received: by mail-pg1-f193.google.com with SMTP id b129-v6so14323159pga.13 for ; Wed, 26 Sep 2018 11:03:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Eg2Mjkb1M+l5w9+ISrAtsAOrO6qEMIH17I1Pv/SmrYg=; b=HE+Tff39dQAvarSfSarMxP10o7T/fKZ7fFZypESU8h08qM8WUAAniAivJLswk6ysXv KVhRbLe7JK9rWYtaRxpMrUNnI1YFoQdo01gXZYhTvPhYD9A7uxGE0h7zwuVepburY1eM FDIEHN+W0PjBPvgPBQ52RmdDEyY4n8fevwsLY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Eg2Mjkb1M+l5w9+ISrAtsAOrO6qEMIH17I1Pv/SmrYg=; b=tb9p4cPVfC/Y/xLorGtbUbB3dd8gSahvSWDkv/FfraDAFjq5pgEXVijrXNAIcz30vB uwR8GeFbZ9Og5oiqP5LqaaQPdgf+3ESBjQpjjNIe1cJHzNVbHjQyT59WiA/CaEiF06y/ E+IUejyFSw16I79yhwU9KPL395gum30zpi7LknJjo5ORY6lfGk3Oo3bemighxszbtoEL Qzcr5PDRpIaSG0YcguQbrr+mNH8EI2qu6OkacMWxdDAqwytXnkJQVPYV6JKJC4BSC9rW erEEhNzsFnl8sGSD8S0IPrls+y2AxU8rM5g26GmkVrwFt8sJsNRf2fZE3o1wIt6kYWkI Ay9w== X-Gm-Message-State: ABuFfoiKr1gVzcurwfXeO8DSCwqaLW98rys0a+/qjyHIV6VKgJg81CZ4 pwtjyHhhqa3wk81uaSdCX7Eehw== X-Google-Smtp-Source: ACcGV61xkjwTo+Zm/vPyTz1GcXwoDQjRSkNoFGmrsaTsh6gbVmvJqOtfnsSE9XJl2N2aoP5A4rlqcA== X-Received: by 2002:a63:fe02:: with SMTP id p2-v6mr6844378pgh.148.1537985012939; Wed, 26 Sep 2018 11:03:32 -0700 (PDT) Received: from smtp.gmail.com ([2620:15c:202:201:7e28:b9f3:6afc:5326]) by smtp.gmail.com with ESMTPSA id j16-v6sm12246816pfk.125.2018.09.26.11.03.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 26 Sep 2018 11:03:12 -0700 (PDT) From: Stephen Boyd To: Andy Gross Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, Mahesh Sivasubramanian , Lina Iyer , Bjorn Andersson , Evan Green Subject: [PATCH v3 1/2] soc: qcom: cmd-db: Remove memcpy()ing from cmd_db_get_header() Date: Wed, 26 Sep 2018 11:02:33 -0700 Message-Id: <20180926180234.55620-2-swboyd@chromium.org> X-Mailer: git-send-email 2.19.0.605.g01d371f741-goog In-Reply-To: <20180926180234.55620-1-swboyd@chromium.org> References: <20180926180234.55620-1-swboyd@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The cmd_db_get_header() function is a static local function that doesn't need to copy anything from one place to another. Instead, it can just point into the region by returning pointers to what we're looking for. If we do that, we should mark what we're returning as const so that code can't modify cmd-db without an obvious cast. Cc: Mahesh Sivasubramanian Cc: Lina Iyer Cc: Bjorn Andersson Cc: Evan Green Signed-off-by: Stephen Boyd --- drivers/soc/qcom/cmd-db.c | 60 +++++++++++++++++---------------------- 1 file changed, 26 insertions(+), 34 deletions(-) diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c index a6f646295f06..5c9cc6824891 100644 --- a/drivers/soc/qcom/cmd-db.c +++ b/drivers/soc/qcom/cmd-db.c @@ -101,8 +101,7 @@ static bool cmd_db_magic_matches(const struct cmd_db_header *header) static struct cmd_db_header *cmd_db_header; - -static inline void *rsc_to_entry_header(struct rsc_hdr *hdr) +static inline const void *rsc_to_entry_header(const struct rsc_hdr *hdr) { u16 offset = le16_to_cpu(hdr->header_offset); @@ -110,7 +109,7 @@ static inline void *rsc_to_entry_header(struct rsc_hdr *hdr) } static inline void * -rsc_offset(struct rsc_hdr *hdr, struct entry_header *ent) +rsc_offset(const struct rsc_hdr *hdr, const struct entry_header *ent) { u16 offset = le16_to_cpu(hdr->data_offset); u16 loffset = le16_to_cpu(ent->offset); @@ -134,11 +133,11 @@ int cmd_db_ready(void) } EXPORT_SYMBOL(cmd_db_ready); -static int cmd_db_get_header(const char *id, struct entry_header *eh, - struct rsc_hdr *rh) +static int cmd_db_get_header(const char *id, const struct entry_header **eh, + const struct rsc_hdr **rh) { - struct rsc_hdr *rsc_hdr; - struct entry_header *ent; + const struct rsc_hdr *rsc_hdr; + const struct entry_header *ent; int ret, i, j; u8 query[8]; @@ -146,9 +145,6 @@ static int cmd_db_get_header(const char *id, struct entry_header *eh, if (ret) return ret; - if (!eh || !rh) - return -EINVAL; - /* Pad out query string to same length as in DB */ strncpy(query, id, sizeof(query)); @@ -159,14 +155,13 @@ static int cmd_db_get_header(const char *id, struct entry_header *eh, ent = rsc_to_entry_header(rsc_hdr); for (j = 0; j < le16_to_cpu(rsc_hdr->cnt); j++, ent++) { - if (memcmp(ent->id, query, sizeof(ent->id)) == 0) - break; - } - - if (j < le16_to_cpu(rsc_hdr->cnt)) { - memcpy(eh, ent, sizeof(*ent)); - memcpy(rh, rsc_hdr, sizeof(*rh)); - return 0; + if (memcmp(ent->id, query, sizeof(ent->id)) == 0) { + if (eh) + *eh = ent; + if (rh) + *rh = rsc_hdr; + return 0; + } } } @@ -186,12 +181,11 @@ static int cmd_db_get_header(const char *id, struct entry_header *eh, u32 cmd_db_read_addr(const char *id) { int ret; - struct entry_header ent; - struct rsc_hdr rsc_hdr; + const struct entry_header *ent; - ret = cmd_db_get_header(id, &ent, &rsc_hdr); + ret = cmd_db_get_header(id, &ent, NULL); - return ret < 0 ? 0 : le32_to_cpu(ent.addr); + return ret < 0 ? 0 : le32_to_cpu(ent->addr); } EXPORT_SYMBOL(cmd_db_read_addr); @@ -207,8 +201,8 @@ EXPORT_SYMBOL(cmd_db_read_addr); int cmd_db_read_aux_data(const char *id, u8 *data, size_t len) { int ret; - struct entry_header ent; - struct rsc_hdr rsc_hdr; + const struct entry_header *ent; + const struct rsc_hdr *rsc_hdr; u16 ent_len; if (!data) @@ -218,12 +212,12 @@ int cmd_db_read_aux_data(const char *id, u8 *data, size_t len) if (ret) return ret; - ent_len = le16_to_cpu(ent.len); + ent_len = le16_to_cpu(ent->len); if (len < ent_len) return -EINVAL; len = min_t(u16, ent_len, len); - memcpy(data, rsc_offset(&rsc_hdr, &ent), len); + memcpy(data, rsc_offset(rsc_hdr, ent), len); return len; } @@ -239,12 +233,11 @@ EXPORT_SYMBOL(cmd_db_read_aux_data); size_t cmd_db_read_aux_data_len(const char *id) { int ret; - struct entry_header ent; - struct rsc_hdr rsc_hdr; + const struct entry_header *ent; - ret = cmd_db_get_header(id, &ent, &rsc_hdr); + ret = cmd_db_get_header(id, &ent, NULL); - return ret < 0 ? 0 : le16_to_cpu(ent.len); + return ret < 0 ? 0 : le16_to_cpu(ent->len); } EXPORT_SYMBOL(cmd_db_read_aux_data_len); @@ -258,15 +251,14 @@ EXPORT_SYMBOL(cmd_db_read_aux_data_len); enum cmd_db_hw_type cmd_db_read_slave_id(const char *id) { int ret; - struct entry_header ent; - struct rsc_hdr rsc_hdr; + const struct entry_header *ent; u32 addr; - ret = cmd_db_get_header(id, &ent, &rsc_hdr); + ret = cmd_db_get_header(id, &ent, NULL); if (ret < 0) return CMD_DB_HW_INVALID; - addr = le32_to_cpu(ent.addr); + addr = le32_to_cpu(ent->addr); return (addr >> SLAVE_ID_SHIFT) & SLAVE_ID_MASK; } EXPORT_SYMBOL(cmd_db_read_slave_id);