From patchwork Tue Feb 16 03:33:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexey Kardashevskiy X-Patchwork-Id: 1440812 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=2404:9400:2:0:216:3eff:fee1:b9f1; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org; receiver=) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2404:9400:2:0:216:3eff:fee1:b9f1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4Dfmld1hNjz9sRN for ; Tue, 16 Feb 2021 14:33:33 +1100 (AEDT) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Dfmld0tQfz3cH2 for ; Tue, 16 Feb 2021 14:33:33 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=ozlabs.ru (client-ip=107.174.27.60; helo=ozlabs.ru; envelope-from=aik@ozlabs.ru; receiver=) Received: from ozlabs.ru (ozlabs.ru [107.174.27.60]) by lists.ozlabs.org (Postfix) with ESMTP id 4DfmlK3cTLz30Gv for ; Tue, 16 Feb 2021 14:33:17 +1100 (AEDT) Received: from fstn1-p1.ozlabs.ibm.com (localhost [IPv6:::1]) by ozlabs.ru (Postfix) with ESMTP id DF05DAE80225; Mon, 15 Feb 2021 22:33:13 -0500 (EST) From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH kernel 1/2] powerpc/iommu: Allocate it_map by vmalloc Date: Tue, 16 Feb 2021 14:33:06 +1100 Message-Id: <20210216033307.69863-2-aik@ozlabs.ru> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210216033307.69863-1-aik@ozlabs.ru> References: <20210216033307.69863-1-aik@ozlabs.ru> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexey Kardashevskiy , kvm-ppc@vger.kernel.org, David Gibson Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" The IOMMU table uses the it_map bitmap to keep track of allocated DMA pages. This has always been a contiguous array allocated at either the boot time or when a passed through device is returned to the host OS. The it_map memory is allocated by alloc_pages() which allocates contiguous physical memory. Such allocation method occasionally creates a problem when there is no big chunk of memory available (no free memory or too fragmented). On powernv/ioda2 the default DMA window requires 16MB for it_map. This replaces alloc_pages_node() with vzalloc_node() which allocates contiguous block but in virtual memory. This should reduce changes of failure but should not cause other behavioral changes as it_map is only used by the kernel's DMA hooks/api when MMU is on. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Reviewed-by: Leonardo Bras --- arch/powerpc/kernel/iommu.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index c00214a4355c..8eb6eb0afa97 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -719,7 +719,6 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid, { unsigned long sz; static int welcomed = 0; - struct page *page; unsigned int i; struct iommu_pool *p; @@ -728,11 +727,9 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid, /* number of bytes needed for the bitmap */ sz = BITS_TO_LONGS(tbl->it_size) * sizeof(unsigned long); - page = alloc_pages_node(nid, GFP_KERNEL, get_order(sz)); - if (!page) + tbl->it_map = vzalloc_node(sz, nid); + if (!tbl->it_map) panic("iommu_init_table: Can't allocate %ld bytes\n", sz); - tbl->it_map = page_address(page); - memset(tbl->it_map, 0, sz); iommu_table_reserve_pages(tbl, res_start, res_end); @@ -774,8 +771,6 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid, static void iommu_table_free(struct kref *kref) { - unsigned long bitmap_sz; - unsigned int order; struct iommu_table *tbl; tbl = container_of(kref, struct iommu_table, it_kref); @@ -796,12 +791,8 @@ static void iommu_table_free(struct kref *kref) if (!bitmap_empty(tbl->it_map, tbl->it_size)) pr_warn("%s: Unexpected TCEs\n", __func__); - /* calculate bitmap size in bytes */ - bitmap_sz = BITS_TO_LONGS(tbl->it_size) * sizeof(unsigned long); - /* free bitmap */ - order = get_order(bitmap_sz); - free_pages((unsigned long) tbl->it_map, order); + vfree(tbl->it_map); /* free table */ kfree(tbl);