From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f73.google.com (mail-ed1-f73.google.com [209.85.208.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 34AAA3C9888 for ; Wed, 13 May 2026 21:52:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778709170; cv=none; b=DCenOuOOS3y3SwNyzikpxDfPwplaPc+mkIVfXfA6/81XloPPRPv7ApVO5HV1vGlH3sfFgdbWrKQgJPVEG3PKo1BrCXU52hiHjEis2kJd9usdnvNZOBGcDnc7Z0j6+tp0anMOQG1RBsZ3oNUF82dlw7PplzEW5rH20a/Pb+BH8Ag= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778709170; c=relaxed/simple; bh=mXVlQJDDIGQCBNIOAsjtzOYRiA0kS/fRbsolMHrau7I=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=V8uSdYJQAN+nU20DtXYuL6N90k1SYL6yU3/Q34213ZC3z2CQ53WL+/e//q8zKLkNSPA12Abn+OKRXQefVnR2cI5ad5L14h76EEk66U744/GNEf5th5d+Eqh/nJTqs2/8fnEYyfLjNTfFfPFJ+FowTu52RuONSkdLMFwayiKs9y0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--smostafa.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ktD13ouW; arc=none smtp.client-ip=209.85.208.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--smostafa.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ktD13ouW" Received: by mail-ed1-f73.google.com with SMTP id 4fb4d7f45d1cf-67bca868649so5431178a12.3 for ; Wed, 13 May 2026 14:52:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1778709167; x=1779313967; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=VmY5S5fM8AoCCFdXEvoltLd2gDk1b3FPoGY3dWz/ZhU=; b=ktD13ouWSztQWxCjQcn/bP7IXASTl/UucZRZy1uPL0dZ2xPIpRsNMeYKAfbcrdCyjN 0/gzmUxTe6UouA2IiNwK9FseE9i71AOK41vo7q42UJPGsNFieGWM4aaFG6JJ6J0V5iXN G+iZaqq4eB9aDNMHtghAM2qyuOt+8G8FTkSW6eQP1XtDzNOiFsq4Kiu7VFblVx2dVviX /7gxYznnbaYiEU5+m5+KxQMko8gXhNGntQfJUSov37kFeJnjE+/8zRic3PQw4QRBXQOp DJFIAMRpGySFX3+CvMj/vvesxe1tYBZwhV3b7gAYV9nLzWpTeVB03KV8s9k4HbrpDBPc 2+qg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778709167; x=1779313967; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=VmY5S5fM8AoCCFdXEvoltLd2gDk1b3FPoGY3dWz/ZhU=; b=jKLAx4Qve8OIArS9x3NkNXF5hMr1G2tKQhNNw7AtoDuPG5xILxPjXpe+wlQAwooe/A zkAaL+idYBbJlKumdzyMCcxjrBDnyoZ4yO4eE8hRLKJClYkZUFWccME/X/e7OgATD6f7 PHkhU1r9zN0TLjnJXm07vJ3RkDzQ6WYE/9M0X/2fhaF9NP0UWHLyMd7W9GGpwPSA+pZ7 KmbjYJNTl9XZgo2ttI3SVu5QLDpcYfS8OW3TLVygxZfrhoJWyCSCPA+XgJ6QIeOJABSn nqn4PHjIwsl/A4yhhCeWhKMFD/hZVSCe9C0Qq3iakhavR2Vu2jeGRg2tmvpsccngGDxU KbEA== X-Forwarded-Encrypted: i=1; AFNElJ8QVYMUhrBB9lGn6DQWx82zAI/D9Rqnt2+FyCGKtORwKsOLUY9Kw9JDqVMDzmdIlmV/bYQc4BR0wAAbrnY=@vger.kernel.org X-Gm-Message-State: AOJu0YxF5wzK8fII0m/O/fhDnL+owim5MFnknSMqmc86HuY8LZogA04V RPveph2JVIcQPjwsYFdYWGVtKcrX4bX67XNlNKmt9783BoZaTia2lw+d2db/qLa0/tP4bLFs8d/ 1Fh9IAeBJx7I/OA== X-Received: from edbel4.prod.google.com ([2002:a05:6402:3604:b0:67c:d93d:89cd]) (user=smostafa job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:8cb:b0:66d:d2f9:520c with SMTP id 4fb4d7f45d1cf-68256d5afa3mr2319843a12.19.1778709167343; Wed, 13 May 2026 14:52:47 -0700 (PDT) Date: Wed, 13 May 2026 21:52:02 +0000 In-Reply-To: <20260513215203.3852661-1-smostafa@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260513215203.3852661-1-smostafa@google.com> X-Mailer: git-send-email 2.54.0.563.g4f69b47b94-goog Message-ID: <20260513215203.3852661-3-smostafa@google.com> Subject: [PATCH 2/3] iommu/io-pgtable-arm: Rework to use the iommu-pages API From: Mostafa Saleh To: iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: robin.murphy@arm.com, will@kernel.org, joro@8bytes.org, jgg@ziepe.ca, Mostafa Saleh Content-Type: text/plain; charset="UTF-8" Update the io-pgtable-arm allocator to use the iommu-pages API. Replace the DMA API usage from __arm_lpae_alloc_pages() with iommu_pages_start_incoherent() and from __arm_lpae_free_pages() with iommu_pages_free_incoherent(). Since the iommu-pages API relies on metadata stored in the struct page during iommu_alloc_pages_node_sz(), it cannot be used safely with memory allocated via the custom cfg->alloc (which may not be backed by pages). So, isolate that logic and keep it as it. Suggested-by: Jason Gunthorpe Signed-off-by: Mostafa Saleh --- drivers/iommu/io-pgtable-arm.c | 79 ++++++++++++++++++++++++---------- 1 file changed, 56 insertions(+), 23 deletions(-) diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index 0cbe545c491d..86b23aa04324 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -248,24 +248,15 @@ static dma_addr_t __arm_lpae_dma_addr(void *pages) return (dma_addr_t)virt_to_phys(pages); } -static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp, - struct io_pgtable_cfg *cfg, - void *cookie) +static void *__arm_lpae_cfg_alloc(size_t size, gfp_t gfp, + struct io_pgtable_cfg *cfg, + void *cookie) { struct device *dev = cfg->iommu_dev; dma_addr_t dma; void *pages; - /* - * For very small starting-level translation tables the HW requires a - * minimum alignment of at least 64 to cover all cases. - */ - size = max(size, 64); - if (cfg->alloc) - pages = cfg->alloc(cookie, size, gfp); - else - pages = iommu_alloc_pages_node_sz(dev_to_node(dev), gfp, size); - + pages = cfg->alloc(cookie, size, gfp); if (!pages) return NULL; @@ -289,14 +280,55 @@ static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp, dma_unmap_single(dev, dma, size, DMA_TO_DEVICE); out_free: - if (cfg->free) - cfg->free(cookie, pages, size); - else - iommu_free_pages(pages); - + cfg->free(cookie, pages, size); return NULL; } +static void __arm_lpae_cfg_free(void *pages, size_t size, + struct io_pgtable_cfg *cfg, + void *cookie) +{ + if (!cfg->coherent_walk) + dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages), + size, DMA_TO_DEVICE); + + cfg->free(cookie, pages, size); +} + +static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp, + struct io_pgtable_cfg *cfg, + void *cookie) +{ + struct device *dev = cfg->iommu_dev; + void *pages; + + /* + * For very small starting-level translation tables the HW requires a + * minimum alignment of at least 64 to cover all cases. + */ + size = max(size, 64); + + if (cfg->alloc) + return __arm_lpae_cfg_alloc(size, gfp, cfg, cookie); + + pages = iommu_alloc_pages_node_sz(dev_to_node(dev), gfp, size); + if (!pages) + return NULL; + + if (!cfg->coherent_walk) { + int ret = iommu_pages_start_incoherent(pages, dev); + + if (ret) { + if (ret == -EOPNOTSUPP) + dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n"); + iommu_free_pages(pages); + return NULL; + } + } + + return pages; +} + static void __arm_lpae_free_pages(void *pages, size_t size, struct io_pgtable_cfg *cfg, void *cookie) @@ -304,12 +336,13 @@ static void __arm_lpae_free_pages(void *pages, size_t size, /* See __arm_lpae_alloc_pages(). */ size = max(size, 64); - if (!cfg->coherent_walk) - dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages), - size, DMA_TO_DEVICE); + if (cfg->free) { + __arm_lpae_cfg_free(pages, size, cfg, cookie); + return; + } - if (cfg->free) - cfg->free(cookie, pages, size); + if (!cfg->coherent_walk) + iommu_pages_free_incoherent(pages, cfg->iommu_dev); else iommu_free_pages(pages); } -- 2.54.0.563.g4f69b47b94-goog