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: 12755432 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 D8E60C433EF for ; Tue, 22 Feb 2022 15:38:18 +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=A63k7mtiMGxkeOBClc3sphKPUId6/86epkLiMwOvU4Q=; b=keswqPc6iQNdRK YhZRBSSV+i1QTM+vaRXvhfrCOsCJvD2gNi30L93L+4U38wRhxJMej8OqcytNeWVs4aEcZXONRwJ+d mvcs3kHtPmYgzfZwO90T8iP8ckc0xV+cknIQ8EUBl/wLFZx1Cj1JONu6eVMN6eUGpoRum5hIEsUCp h59nEOghpp0pEmTjX0uIvjoN2441b0MvvU8e9PjE//gF/Ee3/BtXIg4M8x6n/EKu4FEZjMd6a9GZm btjVs5J7BHx3nSJMKDJhfSY9UQ9hXDfenqERmu3FccYE9esFAeh4XaK0lQfUXJqfEaP1AZDQpgsm5 YTy/ptdGaUAZeYq/alAA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nMXDo-00AHjU-62; Tue, 22 Feb 2022 15:37:00 +0000 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 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-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 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; }