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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1A51FC43334 for ; Fri, 22 Jul 2022 03:39:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231383AbiGVDi6 (ORCPT ); Thu, 21 Jul 2022 23:38:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229605AbiGVDi4 (ORCPT ); Thu, 21 Jul 2022 23:38:56 -0400 Received: from mail-pj1-x102f.google.com (mail-pj1-x102f.google.com [IPv6:2607:f8b0:4864:20::102f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8442E93C25; Thu, 21 Jul 2022 20:38:53 -0700 (PDT) Received: by mail-pj1-x102f.google.com with SMTP id t2-20020a17090a4e4200b001f21572f3a4so3154691pjl.0; Thu, 21 Jul 2022 20:38:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=a29yCrzmqv8zNaI1yMzH3Qx7gYaf2LNG5kNo/fE/DUE=; b=TrKb0Uw+VOc11AVGkutqCQ35Bw+2OmQ0PKMah46laeZkwx582zFO1bWjxQT4FX7RGd LhdU7C39UFnNS8s3iqyC9Z6CLvp/w1nhhkEbYbG/9SCXo7TBJewh+wxWyELhumgfhXt6 R2+F95zKkdFulgQOd+DNL/sMOyrt+/SC3Y7/0IU8VZWpios94Pnw8XppcJMhskyluGYg H1ipqR3UVaOgAJSJRNrDiwRjjBEfVR8AH70AjUU8jd9JSYTRJ/R5cPqItth8K2EfGN5X JbKqW4OfdFX20YZpmC4gb8egLxOfw6yL7s/WuotT0UFOh5DNFt5/xq876gS/db3Uz1v7 KsMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=a29yCrzmqv8zNaI1yMzH3Qx7gYaf2LNG5kNo/fE/DUE=; b=PWmG7Ul7mKm3hTceKwgJ7Km2ZNyPK27R297hP5aOy/+byOvrhMa0tk20F3sfHQt9UH olp28RsKpBtgqc0gcSKj1ci5uqX8lCle5TJtoLQrDbwrOBCoRUma36UW6o84TQReY7Bq BwCjOaLMF4R81ldKi7beJWofo+CPJTOwrRJxsNDkq6Dwr8yi3J1Vi3lW/SM3RpzqUUiX B5VRhx3lW432pq9d0sQ0qCfNcyWsTIQaKuot6QBDdgjege9KKtTMDbYOZeNVacE5MiEm VijE/VFQX69en0rrFoH6wDE1M80KWmWoQrv+x8rTnwA9P4YMgzXzCHX3QKlKFl4yfRuW 9zbQ== X-Gm-Message-State: AJIora+A//g+IFSf4YNhC2DiowW5HLGCdlrTquXj32jsVSLX9ebDvbZr dg56e6B3mfRj3iyS3gXa8wE= X-Google-Smtp-Source: AGRyM1vUUY7kKn/6KhBMe5A/fDpWpu7WshN/fj2ml6WTGt+/r5b8FRKVWzqAbQO/Z1PgJ4A5wm+nhQ== X-Received: by 2002:a17:902:e887:b0:16c:32e4:6446 with SMTP id w7-20020a170902e88700b0016c32e46446mr1417882plg.142.1658461133058; Thu, 21 Jul 2022 20:38:53 -0700 (PDT) Received: from ubuntu-Virtual-Machine.corp.microsoft.com ([2001:4898:80e8:7:d8dc:cc5e:7626:bc3c]) by smtp.gmail.com with ESMTPSA id z2-20020aa79f82000000b005252ab25363sm2521741pfr.206.2022.07.21.20.38.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Jul 2022 20:38:52 -0700 (PDT) From: Tianyu Lan To: hch@infradead.org, m.szyprowski@samsung.com, robin.murphy@arm.com, michael.h.kelley@microsoft.com Cc: Tianyu Lan , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org Subject: [PATCH] swiotlb: Clean up some coding style and minor issues Date: Thu, 21 Jul 2022 23:38:46 -0400 Message-Id: <20220722033846.950237-1-ltykernel@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tianyu Lan - Fix the used field of struct io_tlb_area wasn't initialized - Set area number to be 0 if input area number parameter is 0 - Use array_size() to calculate io_tlb_area array size - Fix error handle of io_tlb_used debugfs node and introduce fops_io_tlb_used attribute - Make parameters of swiotlb_do_find_slots() more reasonable Fixes: 26ffb91fa5e0 ("swiotlb: split up the global swiotlb lock") Signed-off-by: Tianyu Lan --- .../admin-guide/kernel-parameters.txt | 3 +- kernel/dma/swiotlb.c | 42 ++++++++++++------- 2 files changed, 30 insertions(+), 15 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 4a6ad177d4b8..ddca09550f76 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5907,7 +5907,8 @@ Format: { [,] | force | noforce } -- Number of I/O TLB slabs -- Second integer after comma. Number of swiotlb - areas with their own lock. Must be power of 2. + areas with their own lock. Will be rounded up + to a power of 2. force -- force using of bounce buffers even if they wouldn't be automatically used by the kernel noforce -- Never use bounce buffers (for debugging) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index c39483bf067d..5752db98a1f2 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -96,7 +96,13 @@ struct io_tlb_slot { static void swiotlb_adjust_nareas(unsigned int nareas) { - if (!is_power_of_2(nareas)) + /* + * Set area number to 1 when input area number + * is zero. + */ + if (!nareas) + nareas = 1; + else if (!is_power_of_2(nareas)) nareas = roundup_pow_of_two(nareas); default_nareas = nareas; @@ -270,6 +276,7 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start, for (i = 0; i < mem->nareas; i++) { spin_lock_init(&mem->areas[i].lock); mem->areas[i].index = 0; + mem->areas[i].used = 0; } for (i = 0; i < mem->nslabs; i++) { @@ -353,8 +360,8 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags, panic("%s: Failed to allocate %zu bytes align=0x%lx\n", __func__, alloc_size, PAGE_SIZE); - mem->areas = memblock_alloc(sizeof(struct io_tlb_area) * - default_nareas, SMP_CACHE_BYTES); + mem->areas = memblock_alloc(array_size(sizeof(struct io_tlb_area), + default_nareas), SMP_CACHE_BYTES); if (!mem->areas) panic("%s: Failed to allocate mem->areas.\n", __func__); @@ -479,7 +486,7 @@ void __init swiotlb_exit(void) free_pages((unsigned long)mem->slots, get_order(slots_size)); } else { memblock_free_late(__pa(mem->areas), - mem->nareas * sizeof(struct io_tlb_area)); + array_size(sizeof(*mem->areas), mem->nareas)); memblock_free_late(mem->start, tbl_size); memblock_free_late(__pa(mem->slots), slots_size); } @@ -593,11 +600,12 @@ static unsigned int wrap_area_index(struct io_tlb_mem *mem, unsigned int index) * Find a suitable number of IO TLB entries size that will fit this request and * allocate a buffer from that IO TLB pool. */ -static int swiotlb_do_find_slots(struct io_tlb_mem *mem, - struct io_tlb_area *area, int area_index, - struct device *dev, phys_addr_t orig_addr, +static int swiotlb_do_find_slots(struct device *dev, + int area_index, phys_addr_t orig_addr, size_t alloc_size, unsigned int alloc_align_mask) { + struct io_tlb_mem *mem = dev->dma_io_tlb_mem; + struct io_tlb_area *area = mem->areas + area_index; unsigned long boundary_mask = dma_get_seg_boundary(dev); dma_addr_t tbl_dma_addr = phys_to_dma_unencrypted(dev, mem->start) & boundary_mask; @@ -686,13 +694,12 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr, size_t alloc_size, unsigned int alloc_align_mask) { struct io_tlb_mem *mem = dev->dma_io_tlb_mem; - int start = raw_smp_processor_id() & ((1U << __fls(mem->nareas)) - 1); + int start = raw_smp_processor_id() & (mem->nareas - 1); int i = start, index; do { - index = swiotlb_do_find_slots(mem, mem->areas + i, i, - dev, orig_addr, alloc_size, - alloc_align_mask); + index = swiotlb_do_find_slots(dev, i, orig_addr, + alloc_size, alloc_align_mask); if (index >= 0) return index; if (++i >= mem->nareas) @@ -903,17 +910,24 @@ bool is_swiotlb_active(struct device *dev) } EXPORT_SYMBOL_GPL(is_swiotlb_active); +static int io_tlb_used_get(void *data, u64 *val) +{ + *val = mem_used(&io_tlb_default_mem); + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_io_tlb_used, io_tlb_used_get, NULL, "%llu\n"); + static void swiotlb_create_debugfs_files(struct io_tlb_mem *mem, const char *dirname) { - unsigned long used = mem_used(mem); - mem->debugfs = debugfs_create_dir(dirname, io_tlb_default_mem.debugfs); if (!mem->nslabs) return; debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs); - debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &used); + debugfs_create_file_unsafe("io_tlb_used", 0400, mem->debugfs, NULL, + &fops_io_tlb_used); } static int __init __maybe_unused swiotlb_create_default_debugfs(void) -- 2.25.1