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=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 C7682C433B4 for ; Mon, 5 Apr 2021 21:03:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8D80A611AF for ; Mon, 5 Apr 2021 21:03:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235325AbhDEVDX (ORCPT ); Mon, 5 Apr 2021 17:03:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41678 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241230AbhDEVDO (ORCPT ); Mon, 5 Apr 2021 17:03:14 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 160A8C061793 for ; Mon, 5 Apr 2021 14:03:07 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id jp20so368235pjb.2 for ; Mon, 05 Apr 2021 14:03:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Ukibw0pzDXFOw0CkkcldEv36NCXzg19soxuRUFuwOOg=; b=XQxuN2Jo1HK1KRVsWLqHCSpFIXKzCsv9Zp4g2y74XD/nsINPP62fby0eqRnCrZM0Eh 6qfl4lOlusq7SiuIxOlzLmBBvXBRFIWpbrTRP6Nyici7bb1FpCEls8jpPn6spo1d/qtN 52YNrUSvi0Sogaudo+u0klHfh4GcW9cE44Xy922fdVLWWJrrY6rpxWa4xCwocqS2dW8l 2Lgb4Yb45xO2tnQEvA5Dsl8SRQmMu6MP2CgaBPNgu2ZRNeBOck7nYXxZUWRIVJcBvJfy dmSuv49M9NZ/IFaSVgHQYlXlspILXnmK4ZRRXuXFUtefStwphjiyEG/GGoYG+UpDcWr9 2kRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Ukibw0pzDXFOw0CkkcldEv36NCXzg19soxuRUFuwOOg=; b=RKtBGHA4O8cTyEOvCNVKgFyRArWZeTbXtLJF1KikfPJl36jVnhals/WIacznA8eHpd +11qvlQ8X2ZHBVBz29CXMvWBIpy0eDp0aNZ1ebgsxfXeRa1Qbf6PNPa8TL/qfC/mmZaA X/g56rpaMCTGhmjaICPfxUaYfThD8VKcKQsXng90fWzOafD6C4ZZvpUJ/w+k/arGtskK Z8i37hzEC8CuMUbnFWyFXuXunqDLakMe8a5UeMouPfLUtP19QIdb7OT9B0dsG6fiEn0E 0azTMJjkpRyBvUQbw4cvo6DzH47ftwSsWkMp1j+zmZjap5zL169HqRaQ2o4uovBucqlo uvrw== X-Gm-Message-State: AOAM5304q0OJXkXCidMNEirxpjAk4mJAWEmjP6i0W0bwao3CvgbiV3Fo 6CQf10Y6k9jFhkoqWXf/+0YH1DrpE4r03DlToIogRSCtUlWxZpN+4GMzVbtXb0PUS8mpTW5ei2Y u+TE2nqGe3fhYpXZpPvGpYODvmkhbqT7b9Tn1deZLsftL9qQ+a2Wr+4BzEHU= X-Google-Smtp-Source: ABdhPJzPKEZufxeBLFkTxjZ0sxUT1UCCnRZAXjhEAXA4NJ+16lUPeREUyhEQAERYItKXUm+jB1duzp5+Rg== X-Received: from jxgao-snp.c.googlers.com ([fda3:e722:ac3:10:7f:e700:c0a8:1373]) (user=jxgao job=sendgmr) by 2002:a17:902:d351:b029:e8:ba10:e6f5 with SMTP id l17-20020a170902d351b02900e8ba10e6f5mr16726012plk.82.1617656586439; Mon, 05 Apr 2021 14:03:06 -0700 (PDT) Date: Mon, 5 Apr 2021 21:02:27 +0000 In-Reply-To: <20210405210230.1707074-1-jxgao@google.com> Message-Id: <20210405210230.1707074-6-jxgao@google.com> Mime-Version: 1.0 References: <20210405210230.1707074-1-jxgao@google.com> X-Mailer: git-send-email 2.31.0.208.g409f899ff0-goog Subject: [PATCH v5.10 5/8] swiotlb: refactor swiotlb_tbl_map_single From: Jianxiong Gao To: stable@vger.kernel.org Cc: Jianxiong Gao , Christoph Hellwig , Konrad Rzeszutek Wilk Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Christoph Hellwig 'commit 26a7e094783d ("swiotlb: refactor swiotlb_tbl_map_single")' Split out a bunch of a self-contained helpers to make the function easier to follow. Signed-off-by: Christoph Hellwig Acked-by: Jianxiong Gao Tested-by: Jianxiong Gao Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Jianxiong Gao --- kernel/dma/swiotlb.c | 177 +++++++++++++++++++++---------------------- 1 file changed, 86 insertions(+), 91 deletions(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 47d5dfeffd0a..a3c0ccc53b8d 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -452,134 +452,129 @@ static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr, } } -phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr, - size_t mapping_size, size_t alloc_size, - enum dma_data_direction dir, unsigned long attrs) +#define slot_addr(start, idx) ((start) + ((idx) << IO_TLB_SHIFT)) +/* + * Carefully handle integer overflow which can occur when boundary_mask == ~0UL. + */ +static inline unsigned long get_max_slots(unsigned long boundary_mask) { - dma_addr_t tbl_dma_addr = phys_to_dma_unencrypted(hwdev, io_tlb_start); - unsigned long flags; - phys_addr_t tlb_addr; - unsigned int nslots, stride, index, wrap; - int i; - unsigned long mask; - unsigned long offset_slots; - unsigned long max_slots; - unsigned long tmp_io_tlb_used; - - if (no_iotlb_memory) - panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); - - if (mem_encrypt_active()) - pr_warn_once("Memory encryption is active and system is using DMA bounce buffers\n"); - - if (mapping_size > alloc_size) { - dev_warn_once(hwdev, "Invalid sizes (mapping: %zd bytes, alloc: %zd bytes)", - mapping_size, alloc_size); - return (phys_addr_t)DMA_MAPPING_ERROR; - } - - mask = dma_get_seg_boundary(hwdev); - - tbl_dma_addr &= mask; + if (boundary_mask == ~0UL) + return 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); + return nr_slots(boundary_mask + 1); +} - offset_slots = nr_slots(tbl_dma_addr); +static unsigned int wrap_index(unsigned int index) +{ + if (index >= io_tlb_nslabs) + return 0; + return index; +} - /* - * Carefully handle integer overflow which can occur when mask == ~0UL. - */ - max_slots = mask + 1 - ? nr_slots(mask + 1) - : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); +/* + * 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 find_slots(struct device *dev, size_t alloc_size) +{ + unsigned long boundary_mask = dma_get_seg_boundary(dev); + dma_addr_t tbl_dma_addr = + phys_to_dma_unencrypted(dev, io_tlb_start) & boundary_mask; + unsigned long max_slots = get_max_slots(boundary_mask); + unsigned int nslots = nr_slots(alloc_size), stride = 1; + unsigned int index, wrap, count = 0, i; + unsigned long flags; + BUG_ON(!nslots); /* * For mappings greater than or equal to a page, we limit the stride * (and hence alignment) to a page size. */ - nslots = nr_slots(alloc_size); if (alloc_size >= PAGE_SIZE) - stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); - else - stride = 1; + stride <<= (PAGE_SHIFT - IO_TLB_SHIFT); - BUG_ON(!nslots); - - /* - * Find suitable number of IO TLB entries size that will fit this - * request and allocate a buffer from that IO TLB pool. - */ spin_lock_irqsave(&io_tlb_lock, flags); - if (unlikely(nslots > io_tlb_nslabs - io_tlb_used)) goto not_found; - index = ALIGN(io_tlb_index, stride); - if (index >= io_tlb_nslabs) - index = 0; - wrap = index; - + index = wrap = wrap_index(ALIGN(io_tlb_index, stride)); do { - while (iommu_is_span_boundary(index, nslots, offset_slots, - max_slots)) { - index += stride; - if (index >= io_tlb_nslabs) - index = 0; - if (index == wrap) - goto not_found; - } - /* * If we find a slot that indicates we have 'nslots' number of * contiguous buffers, we allocate the buffers from that slot * and mark the entries as '0' indicating unavailable. */ - if (io_tlb_list[index] >= nslots) { - int count = 0; - - for (i = index; i < (int) (index + nslots); i++) - io_tlb_list[i] = 0; - for (i = index - 1; - io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && - io_tlb_list[i]; i--) - io_tlb_list[i] = ++count; - tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT); - - /* - * Update the indices to avoid searching in the next - * round. - */ - io_tlb_index = ((index + nslots) < io_tlb_nslabs - ? (index + nslots) : 0); - - goto found; + if (!iommu_is_span_boundary(index, nslots, + nr_slots(tbl_dma_addr), + max_slots)) { + if (io_tlb_list[index] >= nslots) + goto found; } - index += stride; - if (index >= io_tlb_nslabs) - index = 0; + index = wrap_index(index + stride); } while (index != wrap); not_found: - tmp_io_tlb_used = io_tlb_used; - spin_unlock_irqrestore(&io_tlb_lock, flags); - if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) - dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n", - alloc_size, io_tlb_nslabs, tmp_io_tlb_used); - return (phys_addr_t)DMA_MAPPING_ERROR; + return -1; found: + for (i = index; i < index + nslots; i++) + io_tlb_list[i] = 0; + for (i = index - 1; + io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && + io_tlb_list[i]; i--) + io_tlb_list[i] = ++count; + + /* + * Update the indices to avoid searching in the next round. + */ + if (index + nslots < io_tlb_nslabs) + io_tlb_index = index + nslots; + else + io_tlb_index = 0; io_tlb_used += nslots; + spin_unlock_irqrestore(&io_tlb_lock, flags); + return index; +} +phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, + size_t mapping_size, size_t alloc_size, + enum dma_data_direction dir, unsigned long attrs) +{ + unsigned int index, i; + phys_addr_t tlb_addr; + + if (no_iotlb_memory) + panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); + + if (mem_encrypt_active()) + pr_warn_once("Memory encryption is active and system is using DMA bounce buffers\n"); + + if (mapping_size > alloc_size) { + dev_warn_once(dev, "Invalid sizes (mapping: %zd bytes, alloc: %zd bytes)", + mapping_size, alloc_size); + return (phys_addr_t)DMA_MAPPING_ERROR; + } + + index = find_slots(dev, alloc_size); + if (index == -1) { + if (!(attrs & DMA_ATTR_NO_WARN)) + dev_warn_ratelimited(dev, + "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n", + alloc_size, io_tlb_nslabs, io_tlb_used); + return (phys_addr_t)DMA_MAPPING_ERROR; + } /* * Save away the mapping from the original address to the DMA address. * This is needed when we sync the memory. Then we sync the buffer if * needed. */ - for (i = 0; i < nslots; i++) - io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT); + for (i = 0; i < nr_slots(alloc_size); i++) + io_tlb_orig_addr[index + i] = slot_addr(orig_addr, i); + + tlb_addr = slot_addr(io_tlb_start, index); if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE); - return tlb_addr; } -- 2.27.0