From patchwork Tue Feb 22 15:35:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12755468 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 E477BC433FE for ; Tue, 22 Feb 2022 15:36:38 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.276987.473437 (Exim 4.92) (envelope-from ) id 1nMXDI-0002yv-Tw; Tue, 22 Feb 2022 15:36:28 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 276987.473437; Tue, 22 Feb 2022 15:36:28 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1nMXDI-0002w3-Gk; Tue, 22 Feb 2022 15:36:28 +0000 Received: by outflank-mailman (input) for mailman id 276987; Tue, 22 Feb 2022 15:36:27 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1nMXCY-0005NI-2l for xen-devel@lists.xenproject.org; Tue, 22 Feb 2022 15:35:42 +0000 Received: from bombadil.infradead.org (bombadil.infradead.org [2607:7c80:54:e::133]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 16adb339-93f5-11ec-8539-5f4723681683; Tue, 22 Feb 2022 16:35:40 +0100 (CET) Received: from [2001:4bb8:198:f8fc:c22a:ebfc:be8d:63c2] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nMXCH-00AGql-BP; Tue, 22 Feb 2022 15:35:25 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 16adb339-93f5-11ec-8539-5f4723681683 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=UFY4OZ6N/wy4hplyc9bnUfbK5AWbWfDm8QyseyxAO7o=; b=fXLXkO/oMmt1SoC45j8cVI580X KhuFotBP7XRh1oq2KCz6EchruRdwnkzG4ZcxTnbQVLtkq3kP2o5DFjJjp56+EH5PM1LDnIBiNrybS yQgfvP08+rABWoTJ05VSkwYH1ChMrs8k845H67bcAAmAfZ2U+9r21GydfLpSXQ3lBsZ0pS+9fQ2rm x+/NGz/GeXDT55Ba85crPsBVglG4OptgiOE0FHEv133Jj4hb0w76PzYW/SyPTmW0iJSGmUv/UNt3V uX6eXmBV81r3cKZJvL2MwoIe7oP37qXr7iKycKKD7WtFBxOdwsBGT1Xe9tvqC7DOpEjl7fUemw/0l uz8xIoBw==; From: Christoph Hellwig To: iommu@lists.linux-foundation.org Cc: x86@kernel.org, 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 03/11] swiotlb: simplify swiotlb_max_segment Date: Tue, 22 Feb 2022 16:35:06 +0100 Message-Id: <20220222153514.593231-4-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220222153514.593231-1-hch@lst.de> References: <20220222153514.593231-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html 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 36fbf1181d285..519e363097190 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; }