From patchwork Tue Mar 1 10:53:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12764596 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9DDB9C433F5 for ; Tue, 1 Mar 2022 10:55:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=BxPYXp2ib63pV9jVCvxgM47OP/86EwDGD7SGZ1STWDc=; b=iRsgaeVtfBbZEW rDAiA0K1yS9XiQNU/eqoKVbX/pY7Lv7kQnDYg9eLCf2HRMD/NtBgE15kqRfqeRFPvBuSVcPzrk3yp mzS23rUPh4qCQ6LQaXNvSQSJofnmXnWnG67+JMtrQaLhBtUUnbOhxeDX7/1vfx/FQdJTVxi93M+K9 fiRagvqPPIf8v7EVrWsZFkp5IVEUbX4Nv6cOU5UwxGtzvdDKufPPzaKlLjfhzBRRL1k3w8vTjz8Ll XsJ7HL9EQmbHMabxNPMsPmRaGBmNDnO0hSoaxeezUsJqI9nC0Sx9aIirj5oI26WT0V7kCS2VIawOq n/9iDLtxP5uKPxTbwRHA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nP09U-00GDs0-Rh; Tue, 01 Mar 2022 10:54:45 +0000 Received: from [2.53.44.23] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nP08E-00GCz8-AM; Tue, 01 Mar 2022 10:53:27 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org Cc: x86@kernel.org, Anshuman Khandual , Tom Lendacky , Konrad Rzeszutek Wilk , Stefano Stabellini , Boris Ostrovsky , Juergen Gross , Joerg Roedel , David Woodhouse , Lu Baolu , Robin Murphy , linux-arm-kernel@lists.infradead.org, xen-devel@lists.xenproject.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-hyperv@vger.kernel.org, tboot-devel@lists.sourceforge.net, linux-pci@vger.kernel.org Subject: [PATCH 03/12] swiotlb: simplify swiotlb_max_segment Date: Tue, 1 Mar 2022 12:53:02 +0200 Message-Id: <20220301105311.885699-4-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220301105311.885699-1-hch@lst.de> References: <20220301105311.885699-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Remove the bogus Xen override that was usually larger than the actual size and just calculate the value on demand. Note that swiotlb_max_segment still doesn't make sense as an interface and should eventually be removed. Signed-off-by: Christoph Hellwig Reviewed-by: Anshuman Khandual --- drivers/xen/swiotlb-xen.c | 2 -- include/linux/swiotlb.h | 1 - kernel/dma/swiotlb.c | 20 +++----------------- 3 files changed, 3 insertions(+), 20 deletions(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 47aebd98f52f5..485cd06ed39e7 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -202,7 +202,6 @@ int xen_swiotlb_init(void) rc = swiotlb_late_init_with_tbl(start, nslabs); if (rc) return rc; - swiotlb_set_max_segment(PAGE_SIZE); return 0; error: if (nslabs > 1024 && repeat--) { @@ -254,7 +253,6 @@ void __init xen_swiotlb_init_early(void) if (swiotlb_init_with_tbl(start, nslabs, true)) panic("Cannot allocate SWIOTLB buffer"); - swiotlb_set_max_segment(PAGE_SIZE); } #endif /* CONFIG_X86 */ diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index f6c3638255d54..9fb3a568f0c51 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -164,7 +164,6 @@ static inline void swiotlb_adjust_size(unsigned long size) #endif /* CONFIG_SWIOTLB */ extern void swiotlb_print_info(void); -extern void swiotlb_set_max_segment(unsigned int); #ifdef CONFIG_DMA_RESTRICTED_POOL struct page *swiotlb_alloc(struct device *dev, size_t size); diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 64b390136f9ef..e31c235b5fd9e 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -75,12 +75,6 @@ struct io_tlb_mem io_tlb_default_mem; phys_addr_t swiotlb_unencrypted_base; -/* - * Max segment that we can provide which (if pages are contingous) will - * not be bounced (unless SWIOTLB_FORCE is set). - */ -static unsigned int max_segment; - static unsigned long default_nslabs = IO_TLB_DEFAULT_SIZE >> IO_TLB_SHIFT; static int __init @@ -104,18 +98,12 @@ early_param("swiotlb", setup_io_tlb_npages); unsigned int swiotlb_max_segment(void) { - return io_tlb_default_mem.nslabs ? max_segment : 0; + if (!io_tlb_default_mem.nslabs) + return 0; + return rounddown(io_tlb_default_mem.nslabs << IO_TLB_SHIFT, PAGE_SIZE); } EXPORT_SYMBOL_GPL(swiotlb_max_segment); -void swiotlb_set_max_segment(unsigned int val) -{ - if (swiotlb_force == SWIOTLB_FORCE) - max_segment = 1; - else - max_segment = rounddown(val, PAGE_SIZE); -} - unsigned long swiotlb_size_or_default(void) { return default_nslabs << IO_TLB_SHIFT; @@ -267,7 +255,6 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) if (verbose) swiotlb_print_info(); - swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT); return 0; } @@ -368,7 +355,6 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) swiotlb_init_io_tlb_mem(mem, virt_to_phys(tlb), nslabs, true); swiotlb_print_info(); - swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT); return 0; }