From nobody Thu Dec 25 21:27:29 2025 Received: from mail-yw1-f202.google.com (mail-yw1-f202.google.com [209.85.128.202]) (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 AF8A05C902 for ; Fri, 12 Jan 2024 05:53:06 +0000 (UTC) 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--vannapurve.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="dc/1Xz32" Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-5eb6dba1796so115717227b3.1 for ; Thu, 11 Jan 2024 21:53:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1705038786; x=1705643586; 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=lgNchHS++prR/h3S2HHor+FAVbRKiDRX1egmYCByUjw=; b=dc/1Xz32RIzMrp6QjoBemHExoNQ2PbmRylBdEo1+M89DYNTG7C/ty3KQ6Hg5hD1mG5 o0owqv4GYQ1dH0rMkWwm1IleZ0C2X8l65IVOJHsdgXPhONQa64kK2rsxMY69AMupWu3/ izH5TS6ts1zl89PfymLmlkUR1FLS2S4PJPlaGQwqhnLunbLBwfuAtoadIQNy/Zt/n/qF SeMAPL6kOHJo2V0WfDYQUUu/nazw3IAzF4+y8Knw2wJatJUAhIRQGKCl+gvhUvG23OX9 jZEyul7vpJ1hD256r6mMgvD7ATaaaRyf3PwhnyRYMxZfnoqaZyAwbqYXPHqlz3ceNo8E /gTw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705038786; x=1705643586; 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=lgNchHS++prR/h3S2HHor+FAVbRKiDRX1egmYCByUjw=; b=wt7H4KjsqWtXDw5HUyxbOo7VpmkbWH02jHQ+6gs0kGEngSGd/OCOizcPXTkW8RelCV Wg/1Px9KM6e8gjlhcEEwn985+fLRf1wZ3zAbom4xPc/RdXpDFUi7XkNBHOduc4XeW6PR /ILlzZxzkrRwEACsqT4N6gh8StmUY8jBIQETjkWP32D+BcgLjEenKI1i0GJ80/DtDfBz y3n1bNfj3eyUxR8+UQU5bX151ZVKIbwbxYcttqqg7vUMUvVVvzoxX8KOdCnMgXCwOsvg 48jtvcUiZKisPpNCHBUvEzxJW4Lso/iFadj+l331aAiIRnjOqe1lpemw0loJGiS1AK0j 4B2w== X-Gm-Message-State: AOJu0YzqeaNbEHS8fgT8bXZq2WR7BgQ9pCBkseLwnGsjhhv40H4ktrg5 BfJ99pWSu9z0TlcMfsecZOojlk21hrBavTAXztUc/MU= X-Google-Smtp-Source: AGHT+IHuDn+1jvl5KUmKWmyATHHZ4Buh8nYfelV4isyKtZemvMzYuO4uYtBD4xP91JEeDNYKvgt54kGnaY4QS31H X-Received: from vannapurve2.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:43a4]) (user=vannapurve job=sendgmr) by 2002:a05:6902:1081:b0:dbd:b6cd:92cf with SMTP id v1-20020a056902108100b00dbdb6cd92cfmr144861ybu.11.1705038785851; Thu, 11 Jan 2024 21:53:05 -0800 (PST) Date: Fri, 12 Jan 2024 05:52:48 +0000 In-Reply-To: <20240112055251.36101-1-vannapurve@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240112055251.36101-1-vannapurve@google.com> X-Mailer: git-send-email 2.43.0.275.g3460e3d667-goog Message-ID: <20240112055251.36101-3-vannapurve@google.com> Subject: [RFC V1 2/5] swiotlb: Allow setting up default alignment of SWIOTLB region From: Vishal Annapurve To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: pbonzini@redhat.com, rientjes@google.com, bgardon@google.com, seanjc@google.com, erdemaktas@google.com, ackerleytng@google.com, jxgao@google.com, sagis@google.com, oupton@google.com, peterx@redhat.com, vkuznets@redhat.com, dmatlack@google.com, pgonda@google.com, michael.roth@amd.com, kirill@shutemov.name, thomas.lendacky@amd.com, dave.hansen@linux.intel.com, linux-coco@lists.linux.dev, chao.p.peng@linux.intel.com, isaku.yamahata@gmail.com, andrew.jones@linux.dev, corbet@lwn.net, hch@lst.de, m.szyprowski@samsung.com, bp@suse.de, rostedt@goodmis.org, iommu@lists.linux.dev, Vishal Annapurve Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Allow adjusting alignment of SWIOTLB memory. CVMs can use this framework to align the shared memory regions as needed. Signed-off-by: Vishal Annapurve --- include/linux/swiotlb.h | 5 +++++ kernel/dma/swiotlb.c | 12 +++++++++--- 2 files changed, 14 insertions(+), 3 deletions(-) diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 058901313405..450bd82cdb9f 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -206,6 +206,7 @@ size_t swiotlb_max_mapping_size(struct device *dev); bool is_swiotlb_allocated(void); bool is_swiotlb_active(struct device *dev); void __init swiotlb_adjust_size(unsigned long size); +void __init swiotlb_adjust_alignment(unsigned long alignment); phys_addr_t default_swiotlb_base(void); phys_addr_t default_swiotlb_limit(void); #else @@ -247,6 +248,10 @@ static inline void swiotlb_adjust_size(unsigned long s= ize) { } =20 +void __init swiotlb_adjust_alignment(unsigned long alignment) +{ +} + static inline phys_addr_t default_swiotlb_base(void) { return 0; diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index a056d2f8b9ee..eeab0607a028 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -97,6 +97,7 @@ static struct io_tlb_mem io_tlb_default_mem; #endif /* CONFIG_SWIOTLB_DYNAMIC */ =20 static unsigned long default_nslabs =3D IO_TLB_DEFAULT_SIZE >> IO_TLB_SHIF= T; +static unsigned long default_alignment =3D PAGE_SIZE; static unsigned long default_nareas; =20 /** @@ -223,6 +224,11 @@ void __init swiotlb_adjust_size(unsigned long size) pr_info("SWIOTLB bounce buffer size adjusted to %luMB", size >> 20); } =20 +void __init swiotlb_adjust_alignment(unsigned long alignment) +{ + default_alignment =3D alignment; +} + void swiotlb_print_info(void) { struct io_tlb_pool *mem =3D &io_tlb_default_mem.defpool; @@ -315,7 +321,7 @@ static void __init *swiotlb_memblock_alloc(unsigned lon= g nslabs, unsigned int flags, int (*remap)(void *tlb, unsigned long nslabs)) { - size_t bytes =3D PAGE_ALIGN(nslabs << IO_TLB_SHIFT); + size_t bytes =3D ALIGN(nslabs << IO_TLB_SHIFT, default_alignment); void *tlb; =20 /* @@ -324,9 +330,9 @@ static void __init *swiotlb_memblock_alloc(unsigned lon= g nslabs, * memory encryption. */ if (flags & SWIOTLB_ANY) - tlb =3D memblock_alloc(bytes, PAGE_SIZE); + tlb =3D memblock_alloc(bytes, default_alignment); else - tlb =3D memblock_alloc_low(bytes, PAGE_SIZE); + tlb =3D memblock_alloc_low(bytes, default_alignment); =20 if (!tlb) { pr_warn("%s: Failed to allocate %zu bytes tlb structure\n", --=20 2.43.0.275.g3460e3d667-goog