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=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 B80CBC43387 for ; Wed, 16 Jan 2019 13:44:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7969E206C2 for ; Wed, 16 Jan 2019 13:44:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=baylibre-com.20150623.gappssmtp.com header.i=@baylibre-com.20150623.gappssmtp.com header.b="dDqx49i4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393281AbfAPNog (ORCPT ); Wed, 16 Jan 2019 08:44:36 -0500 Received: from mail-wr1-f66.google.com ([209.85.221.66]:36043 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733175AbfAPNof (ORCPT ); Wed, 16 Jan 2019 08:44:35 -0500 Received: by mail-wr1-f66.google.com with SMTP id u4so6997190wrp.3 for ; Wed, 16 Jan 2019 05:44:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id; bh=DM5tu/r8wrvirg6BCehjKky0y5iqI6RQJjvECDwO6gI=; b=dDqx49i4HCosKdYgHgLE/n5zLXUyu94ivuQbwtK/WBgLPmsY77Lg+3syv/TCwAlGnR xUKr45dwwNdErZ0wdKw+CUIqFPYnEU+XQZ0wiGZ4RNrfE6S7ty2OcqFWpob4SvEMqksK KPBJ9mBfOF9hyf15rrThQ0vrwrabBvH0GbjYx0+R/PC2NW00Srb/c5X1uWeIT3bSyguj RklPz8kqAjZ3d/A1HesCViSKZUiFbaSv33UYh2JfZpF/rvbBt4MefCwmmlfUJ9ED89Te gNG7o3NDX5YhVQS2dpsRM3SIxFOMXkZA/Pa/WLMkAQmUJidtVXr78FpUiOtCnMxFxNkM cUaA== 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; bh=DM5tu/r8wrvirg6BCehjKky0y5iqI6RQJjvECDwO6gI=; b=uQys6IdfcZkwUy/GqoTmcTBiaMNLK7kNZBU0FYRC/vprfpG85gsTIW1ySfbGUJdGtw E98Heblb9gxW5xim4LzaCzKVoeroSqobYOGQtfsvejiqlXjLZfmCdJdy+wcnyjp1ijP8 FME5HIqeKgJNVKUR7ZjQoTeT2HC1llrGx0BM5Y8BH2CL7p6EjJeWOOV5MtNuONBvNcp7 vZrWhfCU9GqB93cPKKLCt+06js/6gmKzEBy5oAbzc7JBAWplQXvyZ5vAQ7XtsjfloPb2 skcYZ0Yf5xszDTpRnTEWEvTZ0SsbWanzW1qCMi1zEBm5y3AST43I/k1ZQwHwiWa5Uket etFA== X-Gm-Message-State: AJcUukdE7gwor753SnOs8R6ZadV4SaPyZel+2m95VmSWptq5y4ZNG76J cS1GBUG47CJk7JCr3YPBTehSUtGz5g4= X-Google-Smtp-Source: ALg8bN6W8lF0MoSyz38fb3CTkBMR2Wew8oSQp+BJq2ozI/be6CaFoqdlxPqPkCwYQF4plQ+lP36+UA== X-Received: by 2002:adf:b190:: with SMTP id q16mr7649235wra.95.1547646273608; Wed, 16 Jan 2019 05:44:33 -0800 (PST) Received: from localhost.localdomain ([51.15.160.169]) by smtp.googlemail.com with ESMTPSA id i13sm71014746wrw.32.2019.01.16.05.44.32 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 16 Jan 2019 05:44:32 -0800 (PST) From: Corentin Labbe To: hch@lst.de, m.szyprowski@samsung.com, robin.murphy@arm.com Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Corentin Labbe Subject: [PATCH] dma-debug: add dumping facility via debugfs Date: Wed, 16 Jan 2019 13:44:25 +0000 Message-Id: <1547646265-9414-1-git-send-email-clabbe@baylibre.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While debugging a DMA mapping leak, I needed to access debug_dma_dump_mappings() but easily from user space. This patch adds a /sys/kernel/debug/dma-api/dump file which contain all current DMA mapping. Signed-off-by: Corentin Labbe --- kernel/dma/debug.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 23cf5361bcf1..9253382f5729 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -144,6 +144,7 @@ static struct dentry *num_free_entries_dent __read_mostly; static struct dentry *min_free_entries_dent __read_mostly; static struct dentry *nr_total_entries_dent __read_mostly; static struct dentry *filter_dent __read_mostly; +static struct dentry *dump_dent __read_mostly; /* per-driver filter related state */ @@ -840,6 +841,47 @@ static const struct file_operations filter_fops = { .llseek = default_llseek, }; +static int dump_read(struct seq_file *seq, void *v) +{ + int idx; + + for (idx = 0; idx < HASH_SIZE; idx++) { + struct hash_bucket *bucket = &dma_entry_hash[idx]; + struct dma_debug_entry *entry; + unsigned long flags; + + spin_lock_irqsave(&bucket->lock, flags); + + list_for_each_entry(entry, &bucket->list, list) { + seq_printf(seq, + "%s %s %s idx %d P=%llx N=%lx D=%llx L=%llx %s %s\n", + dev_name(entry->dev), + dev_driver_string(entry->dev), + type2name[entry->type], idx, + phys_addr(entry), entry->pfn, + entry->dev_addr, entry->size, + dir2name[entry->direction], + maperr2str[entry->map_err_type]); + } + + spin_unlock_irqrestore(&bucket->lock, flags); + } + return 0; +} + +static int dump_open(struct inode *inode, struct file *file) +{ + return single_open(file, dump_read, inode->i_private); +} + +static const struct file_operations dump_fops = { + .owner = THIS_MODULE, + .open = dump_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + static int dma_debug_fs_init(void) { dma_debug_dent = debugfs_create_dir("dma-api", NULL); @@ -894,6 +936,11 @@ static int dma_debug_fs_init(void) if (!filter_dent) goto out_err; + dump_dent = debugfs_create_file("dump", 0444, + dma_debug_dent, NULL, &dump_fops); + if (!dump_dent) + goto out_err; + return 0; out_err: -- 2.19.2