From patchwork Fri Mar 18 15:09:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 12785457 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 A003CC433F5 for ; Fri, 18 Mar 2022 15:18:15 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.292078.496017 (Exim 4.92) (envelope-from ) id 1nVEMS-0007YF-Ak; Fri, 18 Mar 2022 15:17:52 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 292078.496017; Fri, 18 Mar 2022 15:17:52 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1nVEMS-0007Y8-6j; Fri, 18 Mar 2022 15:17:52 +0000 Received: by outflank-mailman (input) for mailman id 292078; Fri, 18 Mar 2022 15:17:51 +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 1nVEEk-0003m0-Rk for xen-devel@lists.xenproject.org; Fri, 18 Mar 2022 15:09:55 +0000 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 76af0077-a6cd-11ec-8eba-a37418f5ba1a; Fri, 18 Mar 2022 16:09:53 +0100 (CET) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id C71D51F390; Fri, 18 Mar 2022 15:09:52 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 7F68D13B67; Fri, 18 Mar 2022 15:09:52 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id NoXgHcCgNGIHWgAAMHmgww (envelope-from ); Fri, 18 Mar 2022 15:09:52 +0000 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: 76af0077-a6cd-11ec-8eba-a37418f5ba1a DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1647616192; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=RxF60QtrY1fK+g68vrfHEjQXsgUXbBosZMnbmksQM/w=; b=NH9TcO2niB0Ndeajg0NZtMfFDLtrh3K7bBXW6kn66V1InFoOQ8LrZ0GtCbQ91ZorrjxQ5f 0Zxj6vFffPG0BjL7fznqUI4/qAjvCCERPrF5kGpUDNFqk4AdFpEFgmEeVeYGZdr2cGozwG mT4TQfyrOT/HA8ImsIZR4nULGD5on5M= From: Juergen Gross To: xen-devel@lists.xenproject.org, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, Dell.Client.Kernel@dell.com Cc: Juergen Gross , Stuart Hayes , Hans de Goede , Mark Gross , stable@vger.kernel.org Subject: [PATCH] platform/x86/dell: add buffer allocation/free functions for SMI calls Date: Fri, 18 Mar 2022 16:09:50 +0100 Message-Id: <20220318150950.16843-1-jgross@suse.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 The dcdbas driver is used to call SMI handlers for both, dcdbas and dell-smbios-smm. Both drivers allocate a buffer for communicating with the SMI handler. The physical buffer address is then passed to the called SMI handler via %ebx. Unfortunately this doesn't work when running in Xen dom0, as the physical address obtained via virt_to_phys() is only a guest physical address, and not a machine physical address as needed by SMI. The problem in dcdbas is easy to correct, as dcdbas is using dma_alloc_coherent() for allocating the buffer, and the machine physical address is available via the DMA address returned in the DMA handle. In order to avoid duplicating the buffer allocation code in dell-smbios-smm, add a generic buffer allocation function to dcdbas and use it for both drivers. This is especially fine regarding driver dependencies, as dell-smbios-smm is already calling dcdbas to generate the SMI request. Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross --- drivers/platform/x86/dell/dcdbas.c | 127 +++++++++++--------- drivers/platform/x86/dell/dcdbas.h | 9 ++ drivers/platform/x86/dell/dell-smbios-smm.c | 14 ++- 3 files changed, 87 insertions(+), 63 deletions(-) diff --git a/drivers/platform/x86/dell/dcdbas.c b/drivers/platform/x86/dell/dcdbas.c index 5e63d6225048..02bcac619018 100644 --- a/drivers/platform/x86/dell/dcdbas.c +++ b/drivers/platform/x86/dell/dcdbas.c @@ -40,13 +40,10 @@ static struct platform_device *dcdbas_pdev; -static u8 *smi_data_buf; -static dma_addr_t smi_data_buf_handle; -static unsigned long smi_data_buf_size; static unsigned long max_smi_data_buf_size = MAX_SMI_DATA_BUF_SIZE; -static u32 smi_data_buf_phys_addr; static DEFINE_MUTEX(smi_data_lock); static u8 *bios_buffer; +static struct smi_buffer smi_buf; static unsigned int host_control_action; static unsigned int host_control_smi_type; @@ -54,23 +51,49 @@ static unsigned int host_control_on_shutdown; static bool wsmt_enabled; +int dcdbas_smi_alloc(struct smi_buffer *smi_buffer, unsigned long size) +{ + smi_buffer->virt = dma_alloc_coherent(&dcdbas_pdev->dev, size, + &smi_buffer->dma, GFP_KERNEL); + if (!smi_buffer->virt) { + dev_dbg(&dcdbas_pdev->dev, + "%s: failed to allocate memory size %lu\n", + __func__, size); + return -ENOMEM; + } + smi_buffer->size = size; + + dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", + __func__, (u32)smi_buffer->dma, smi_buffer->size); + + return 0; +} +EXPORT_SYMBOL_GPL(dcdbas_smi_alloc); + +void dcdbas_smi_free(struct smi_buffer *smi_buffer) +{ + if (!smi_buffer->virt) + return; + + dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", + __func__, (u32)smi_buffer->dma, smi_buffer->size); + dma_free_coherent(&dcdbas_pdev->dev, smi_buffer->size, + smi_buffer->virt, smi_buffer->dma); + smi_buffer->virt = NULL; + smi_buffer->dma = 0; + smi_buffer->size = 0; +} +EXPORT_SYMBOL_GPL(dcdbas_smi_free); + /** * smi_data_buf_free: free SMI data buffer */ static void smi_data_buf_free(void) { - if (!smi_data_buf || wsmt_enabled) + if (!smi_buf.virt || wsmt_enabled) return; - dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", - __func__, smi_data_buf_phys_addr, smi_data_buf_size); - - dma_free_coherent(&dcdbas_pdev->dev, smi_data_buf_size, smi_data_buf, - smi_data_buf_handle); - smi_data_buf = NULL; - smi_data_buf_handle = 0; - smi_data_buf_phys_addr = 0; - smi_data_buf_size = 0; + dcdbas_smi_free(&smi_buf); } /** @@ -78,39 +101,29 @@ static void smi_data_buf_free(void) */ static int smi_data_buf_realloc(unsigned long size) { - void *buf; - dma_addr_t handle; + struct smi_buffer tmp; + int ret; - if (smi_data_buf_size >= size) + if (smi_buf.size >= size) return 0; if (size > max_smi_data_buf_size) return -EINVAL; /* new buffer is needed */ - buf = dma_alloc_coherent(&dcdbas_pdev->dev, size, &handle, GFP_KERNEL); - if (!buf) { - dev_dbg(&dcdbas_pdev->dev, - "%s: failed to allocate memory size %lu\n", - __func__, size); - return -ENOMEM; - } - /* memory zeroed by dma_alloc_coherent */ + ret = dcdbas_smi_alloc(&tmp, size); + if (ret) + return ret; - if (smi_data_buf) - memcpy(buf, smi_data_buf, smi_data_buf_size); + /* memory zeroed by dma_alloc_coherent */ + if (smi_buf.virt) + memcpy(tmp.virt, smi_buf.virt, smi_buf.size); /* free any existing buffer */ smi_data_buf_free(); /* set up new buffer for use */ - smi_data_buf = buf; - smi_data_buf_handle = handle; - smi_data_buf_phys_addr = (u32) virt_to_phys(buf); - smi_data_buf_size = size; - - dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", - __func__, smi_data_buf_phys_addr, smi_data_buf_size); + smi_buf = tmp; return 0; } @@ -119,14 +132,14 @@ static ssize_t smi_data_buf_phys_addr_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%x\n", smi_data_buf_phys_addr); + return sprintf(buf, "%x\n", (u32)smi_buf.dma); } static ssize_t smi_data_buf_size_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%lu\n", smi_data_buf_size); + return sprintf(buf, "%lu\n", smi_buf.size); } static ssize_t smi_data_buf_size_store(struct device *dev, @@ -155,8 +168,8 @@ static ssize_t smi_data_read(struct file *filp, struct kobject *kobj, ssize_t ret; mutex_lock(&smi_data_lock); - ret = memory_read_from_buffer(buf, count, &pos, smi_data_buf, - smi_data_buf_size); + ret = memory_read_from_buffer(buf, count, &pos, smi_buf.virt, + smi_buf.size); mutex_unlock(&smi_data_lock); return ret; } @@ -176,7 +189,7 @@ static ssize_t smi_data_write(struct file *filp, struct kobject *kobj, if (ret) goto out; - memcpy(smi_data_buf + pos, buf, count); + memcpy(smi_buf.virt + pos, buf, count); ret = count; out: mutex_unlock(&smi_data_lock); @@ -306,11 +319,11 @@ static ssize_t smi_request_store(struct device *dev, mutex_lock(&smi_data_lock); - if (smi_data_buf_size < sizeof(struct smi_cmd)) { + if (smi_buf.size < sizeof(struct smi_cmd)) { ret = -ENODEV; goto out; } - smi_cmd = (struct smi_cmd *)smi_data_buf; + smi_cmd = (struct smi_cmd *)smi_buf.virt; switch (val) { case 2: @@ -326,20 +339,20 @@ static ssize_t smi_request_store(struct device *dev, * Provide physical address of command buffer field within * the struct smi_cmd to BIOS. * - * Because the address that smi_cmd (smi_data_buf) points to + * Because the address that smi_cmd (smi_buf.virt) points to * will be from memremap() of a non-memory address if WSMT * is present, we can't use virt_to_phys() on smi_cmd, so * we have to use the physical address that was saved when * the virtual address for smi_cmd was received. */ - smi_cmd->ebx = smi_data_buf_phys_addr + + smi_cmd->ebx = (u32)smi_buf.dma + offsetof(struct smi_cmd, command_buffer); ret = dcdbas_smi_request(smi_cmd); if (!ret) ret = count; break; case 0: - memset(smi_data_buf, 0, smi_data_buf_size); + memset(smi_buf.virt, 0, smi_buf.size); ret = count; break; default: @@ -356,7 +369,7 @@ EXPORT_SYMBOL(dcdbas_smi_request); /** * host_control_smi: generate host control SMI * - * Caller must set up the host control command in smi_data_buf. + * Caller must set up the host control command in smi_buf.virt. */ static int host_control_smi(void) { @@ -367,14 +380,14 @@ static int host_control_smi(void) s8 cmd_status; u8 index; - apm_cmd = (struct apm_cmd *)smi_data_buf; + apm_cmd = (struct apm_cmd *)smi_buf.virt; apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL; switch (host_control_smi_type) { case HC_SMITYPE_TYPE1: spin_lock_irqsave(&rtc_lock, flags); /* write SMI data buffer physical address */ - data = (u8 *)&smi_data_buf_phys_addr; + data = (u8 *)&smi_buf.dma; for (index = PE1300_CMOS_CMD_STRUCT_PTR; index < (PE1300_CMOS_CMD_STRUCT_PTR + 4); index++, data++) { @@ -405,7 +418,7 @@ static int host_control_smi(void) case HC_SMITYPE_TYPE3: spin_lock_irqsave(&rtc_lock, flags); /* write SMI data buffer physical address */ - data = (u8 *)&smi_data_buf_phys_addr; + data = (u8 *)&smi_buf.dma; for (index = PE1400_CMOS_CMD_STRUCT_PTR; index < (PE1400_CMOS_CMD_STRUCT_PTR + 4); index++, data++) { @@ -450,7 +463,7 @@ static int host_control_smi(void) * This function is called by the driver after the system has * finished shutting down if the user application specified a * host control action to perform on shutdown. It is safe to - * use smi_data_buf at this point because the system has finished + * use smi_buf.virt at this point because the system has finished * shutting down and no userspace apps are running. */ static void dcdbas_host_control(void) @@ -464,18 +477,18 @@ static void dcdbas_host_control(void) action = host_control_action; host_control_action = HC_ACTION_NONE; - if (!smi_data_buf) { + if (!smi_buf.virt) { dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__); return; } - if (smi_data_buf_size < sizeof(struct apm_cmd)) { + if (smi_buf.size < sizeof(struct apm_cmd)) { dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n", __func__); return; } - apm_cmd = (struct apm_cmd *)smi_data_buf; + apm_cmd = (struct apm_cmd *)smi_buf.virt; /* power off takes precedence */ if (action & HC_ACTION_HOST_CONTROL_POWEROFF) { @@ -583,11 +596,11 @@ static int dcdbas_check_wsmt(void) return -ENOMEM; } - /* First 8 bytes is for a semaphore, not part of the smi_data_buf */ - smi_data_buf_phys_addr = bios_buf_paddr + 8; - smi_data_buf = bios_buffer + 8; - smi_data_buf_size = remap_size - 8; - max_smi_data_buf_size = smi_data_buf_size; + /* First 8 bytes is for a semaphore, not part of the smi_buf.virt */ + smi_buf.dma = bios_buf_paddr + 8; + smi_buf.virt = bios_buffer + 8; + smi_buf.size = remap_size - 8; + max_smi_data_buf_size = smi_buf.size; wsmt_enabled = true; dev_info(&dcdbas_pdev->dev, "WSMT found, using firmware-provided SMI buffer.\n"); diff --git a/drivers/platform/x86/dell/dcdbas.h b/drivers/platform/x86/dell/dcdbas.h index c3cca5433525..942a23ddded0 100644 --- a/drivers/platform/x86/dell/dcdbas.h +++ b/drivers/platform/x86/dell/dcdbas.h @@ -105,5 +105,14 @@ struct smm_eps_table { u64 num_of_4k_pages; } __packed; +struct smi_buffer { + u8 *virt; + unsigned long size; + dma_addr_t dma; +}; + +int dcdbas_smi_alloc(struct smi_buffer *smi_buffer, unsigned long size); +void dcdbas_smi_free(struct smi_buffer *smi_buffer); + #endif /* _DCDBAS_H_ */ diff --git a/drivers/platform/x86/dell/dell-smbios-smm.c b/drivers/platform/x86/dell/dell-smbios-smm.c index 320c032418ac..4d375985c85f 100644 --- a/drivers/platform/x86/dell/dell-smbios-smm.c +++ b/drivers/platform/x86/dell/dell-smbios-smm.c @@ -20,6 +20,7 @@ static int da_command_address; static int da_command_code; +static struct smi_buffer smi_buf; static struct calling_interface_buffer *buffer; static struct platform_device *platform_device; static DEFINE_MUTEX(smm_mutex); @@ -57,7 +58,7 @@ static int dell_smbios_smm_call(struct calling_interface_buffer *input) command.magic = SMI_CMD_MAGIC; command.command_address = da_command_address; command.command_code = da_command_code; - command.ebx = virt_to_phys(buffer); + command.ebx = smi_buf.dma; command.ecx = 0x42534931; mutex_lock(&smm_mutex); @@ -101,9 +102,10 @@ int init_dell_smbios_smm(void) * Allocate buffer below 4GB for SMI data--only 32-bit physical addr * is passed to SMI handler. */ - buffer = (void *)__get_free_page(GFP_KERNEL | GFP_DMA32); - if (!buffer) - return -ENOMEM; + ret = dcdbas_smi_alloc(&smi_buf, PAGE_SIZE); + if (ret) + return ret; + buffer = (void *)smi_buf.virt; dmi_walk(find_cmd_address, NULL); @@ -138,7 +140,7 @@ int init_dell_smbios_smm(void) fail_wsmt: fail_platform_device_alloc: - free_page((unsigned long)buffer); + dcdbas_smi_free(&smi_buf); return ret; } @@ -147,6 +149,6 @@ void exit_dell_smbios_smm(void) if (platform_device) { dell_smbios_unregister_device(&platform_device->dev); platform_device_unregister(platform_device); - free_page((unsigned long)buffer); + dcdbas_smi_free(&smi_buf); } }