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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A57ACC072B5 for ; Fri, 24 May 2019 20:16:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 849F52133D for ; Fri, 24 May 2019 20:16:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391826AbfEXUQQ (ORCPT ); Fri, 24 May 2019 16:16:16 -0400 Received: from ale.deltatee.com ([207.54.116.67]:33756 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391817AbfEXUQQ (ORCPT ); Fri, 24 May 2019 16:16:16 -0400 Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hUGbu-00032O-CE; Fri, 24 May 2019 14:16:15 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.89) (envelope-from ) id 1hUGbu-00026S-7R; Fri, 24 May 2019 14:16:14 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Cc: Bjorn Helgaas , Logan Gunthorpe Date: Fri, 24 May 2019 14:16:08 -0600 Message-Id: <20190524201610.8039-2-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190524201610.8039-1-logang@deltatee.com> References: <20190524201610.8039-1-logang@deltatee.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, bhelgaas@google.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH 1/3] PCI: Clean up resource_alignment parameter to not require static buffer X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Clean up the 'resource_alignment' parameter code to use kstrdup in the initcall routine instead of a static buffer that wastes memory regardless of whether the feature is used. This allows us to drop 'COMMAND_LINE_SIZE' bytes (typically 256-4096 depending on architecture) of static data. This is similar to what has been done for the 'disable_acs_redir' parameter. Signed-off-by: Logan Gunthorpe Cc: Bjorn Helgaas --- drivers/pci/pci.c | 41 +++++++++++++++++++++++------------------ 1 file changed, 23 insertions(+), 18 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 766f5779db92..bd7cdcfeb094 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5896,8 +5896,7 @@ resource_size_t __weak pcibios_default_alignment(void) return 0; } -#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE -static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0}; +static char *resource_alignment_param; static DEFINE_SPINLOCK(resource_alignment_lock); /** @@ -5918,7 +5917,7 @@ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev, spin_lock(&resource_alignment_lock); p = resource_alignment_param; - if (!*p && !align) + if (!p || !*p) goto out; if (pci_has_flag(PCI_PROBE_ONLY)) { align = 0; @@ -6084,21 +6083,25 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) static ssize_t pci_set_resource_alignment_param(const char *buf, size_t count) { - if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1) - count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1; spin_lock(&resource_alignment_lock); - strncpy(resource_alignment_param, buf, count); - resource_alignment_param[count] = '\0'; + + kfree(resource_alignment_param); + resource_alignment_param = kstrndup(buf, count, GFP_KERNEL); + spin_unlock(&resource_alignment_lock); - return count; + + return resource_alignment_param ? count : -ENOMEM; } static ssize_t pci_get_resource_alignment_param(char *buf, size_t size) { - size_t count; + size_t count = 0; + spin_lock(&resource_alignment_lock); - count = snprintf(buf, size, "%s", resource_alignment_param); + if (resource_alignment_param) + count = snprintf(buf, size, "%s", resource_alignment_param); spin_unlock(&resource_alignment_lock); + return count; } @@ -6238,8 +6241,7 @@ static int __init pci_setup(char *str) } else if (!strncmp(str, "cbmemsize=", 10)) { pci_cardbus_mem_size = memparse(str + 10, &str); } else if (!strncmp(str, "resource_alignment=", 19)) { - pci_set_resource_alignment_param(str + 19, - strlen(str + 19)); + resource_alignment_param = str + 19; } else if (!strncmp(str, "ecrc=", 5)) { pcie_ecrc_get_policy(str + 5); } else if (!strncmp(str, "hpiosize=", 9)) { @@ -6275,15 +6277,18 @@ static int __init pci_setup(char *str) early_param("pci", pci_setup); /* - * 'disable_acs_redir_param' is initialized in pci_setup(), above, to point - * to data in the __initdata section which will be freed after the init - * sequence is complete. We can't allocate memory in pci_setup() because some - * architectures do not have any memory allocation service available during - * an early_param() call. So we allocate memory and copy the variable here - * before the init section is freed. + * 'resource_alignment_param' and 'disable_acs_redir_param' are initialized + * in pci_setup(), above, to point to data in the __initdata section which + * will be freed after the init sequence is complete. We can't allocate memory + * in pci_setup() because some architectures do not have any memory allocation + * service available during an early_param() call. So we allocate memory and + * copy the variable here before the init section is freed. + * */ static int __init pci_realloc_setup_params(void) { + resource_alignment_param = kstrdup(resource_alignment_param, + GFP_KERNEL); disable_acs_redir_param = kstrdup(disable_acs_redir_param, GFP_KERNEL); return 0; -- 2.20.1