From mboxrd@z Thu Jan 1 00:00:00 1970 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA21BC433EF for ; Wed, 17 Nov 2021 11:52:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5B0F963215 for ; Wed, 17 Nov 2021 11:52:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 5B0F963215 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id D2B836B0072; Wed, 17 Nov 2021 06:52:14 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id CB45A6B0073; Wed, 17 Nov 2021 06:52:14 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B7BBA6B0074; Wed, 17 Nov 2021 06:52:14 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0224.hostedemail.com [216.40.44.224]) by kanga.kvack.org (Postfix) with ESMTP id A1F086B0072 for ; Wed, 17 Nov 2021 06:52:14 -0500 (EST) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 693DA84A20 for ; Wed, 17 Nov 2021 11:52:04 +0000 (UTC) X-FDA: 78818258568.03.03E299B Received: from mail-yb1-f178.google.com (mail-yb1-f178.google.com [209.85.219.178]) by imf31.hostedemail.com (Postfix) with ESMTP id 8ADD2105298C for ; Wed, 17 Nov 2021 11:52:03 +0000 (UTC) Received: by mail-yb1-f178.google.com with SMTP id s186so6640969yba.12 for ; Wed, 17 Nov 2021 03:52:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=IXJmB9DsrkP0Hl2X6TbOwJcxLtK5wGiHx+4l+DLgyu0=; b=UvbMV3fyqh6gAOb0SdTanMwPJxP/u4+ZL3yFDfKzV1czXOZixPZVswla4YNGlaenLr 2DEy1i1zqG2tkdnwMSE9O8bQcuFyULUcaaemhydffoKdJlzSTM4s0we6p1r0IiL+G0hh fjp1nklrcymDLzodFWHrg8DwSt6lN4TyT7b3WdJwp/wO8cac6NvWRTELTwUJfAGhetlm RQaODfMP4oI5RRf6Tnq2M8cPUJGJnhU+EfFn8rqdhlP+A9Zmf3+isI1QbteEbjukex08 06569AbcdlEuTVYeEBsqzQyjTQsynuwlbmbTwvtYdvcd/dCCQ/Un8d9C4QHY4r41JL9y LaKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=IXJmB9DsrkP0Hl2X6TbOwJcxLtK5wGiHx+4l+DLgyu0=; b=R3bu79yAVEl7jlhOzkYlS2kKLgisLgeMevu6Ho1+zmIDawKmLz5J1IlzXyU/nSdqRU KEi+W1xQ9bsWAXuOvrswcPzG4hpbzHzD6wKzFjarwFuZdwpQjOVTSyKHjM98AQvrgVpw 5whIw6284zhXNaC+zRajS4Z9IcrBCNENpJ0iaKbPHgs8pHa+DEdfuh+pTAgP3MvEk1wd pUOO22HQTPEJ47SxuzVRAcar0tSo73B5qXruBQyaxrYfledLGg7xWVMikxX5pxuRu1m6 m90QIiYvbep92G+CCgKL9HBn486vQ1WF/sLASMPPYLEL6QrY6W4xB5uUTZW9LkIoXnU2 CS9A== X-Gm-Message-State: AOAM530Ih7nqPimuYlUBxdjYbzuOuw+BX2dwme9u0ToK2RHQp7ZBzHm4 FClFiUcZVClt1gss2pDdCpl/rlkxe47DShftEvC5hg== X-Google-Smtp-Source: ABdhPJz2VtCKhzu8qZQihL+co6Mjb8uHqzCSoeW/gU9T0TjHNu8foK/mFxIYBP2LjWFnrz17Dbu/9zaW30o6I6X2Gy0= X-Received: by 2002:a25:c68a:: with SMTP id k132mr16877021ybf.531.1637149923308; Wed, 17 Nov 2021 03:52:03 -0800 (PST) MIME-Version: 1.0 References: <20211117075652.58299-1-linyunsheng@huawei.com> In-Reply-To: From: Ilias Apalodimas Date: Wed, 17 Nov 2021 13:51:27 +0200 Message-ID: Subject: Re: [PATCH net] page_pool: Revert "page_pool: disable dma mapping support..." To: Jesper Dangaard Brouer Cc: Yunsheng Lin , davem@davemloft.net, kuba@kernel.org, brouer@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linuxarm@openeuler.org, hawk@kernel.org, akpm@linux-foundation.org, peterz@infradead.org, vbabka@suse.cz, willy@infradead.org, will@kernel.org, feng.tang@intel.com, jgg@ziepe.ca, ebiederm@xmission.com, aarcange@redhat.com, guillaume.tucker@collabora.com, Linux-MM Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 8ADD2105298C Authentication-Results: imf31.hostedemail.com; dkim=pass header.d=linaro.org header.s=google header.b=UvbMV3fy; dmarc=pass (policy=none) header.from=linaro.org; spf=pass (imf31.hostedemail.com: domain of ilias.apalodimas@linaro.org designates 209.85.219.178 as permitted sender) smtp.mailfrom=ilias.apalodimas@linaro.org X-Stat-Signature: sdtcfgs8kx6x9pqsdtewuw5jqwwf193o X-HE-Tag: 1637149923-4619 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 17 Nov 2021 at 13:48, Jesper Dangaard Brouer wrote: > > Added CC: linux-mm@kvack.org > > On 17/11/2021 08.56, Yunsheng Lin wrote: > > This reverts commit d00e60ee54b12de945b8493cf18c1ada9e422514. > > > > As reported by Guillaume in [1]: > > Enabling LPAE always enables CONFIG_ARCH_DMA_ADDR_T_64BIT > > in 32-bit systems, which breaks the bootup proceess when a > > ethernet driver is using page pool with PP_FLAG_DMA_MAP flag. > > As we were hoping we had no active consumers for such system > > when we removed the dma mapping support, and LPAE seems like > > a common feature for 32 bits system, so revert it. > > > > 1. https://www.spinics.net/lists/netdev/msg779890.html > > > > Fixes: d00e60ee54b1 ("page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA") > > Signed-off-by: Yunsheng Lin > > --- > > include/linux/mm_types.h | 13 ++++++++++++- > > include/net/page_pool.h | 12 +++++++++++- > > net/core/page_pool.c | 10 ++++------ > > 3 files changed, 27 insertions(+), 8 deletions(-) > > Acked-by: Jesper Dangaard Brouer > > Too bad that we have to keep this code-uglyness in struct page, and > handling in page_pool. Indeed :( Acked-by: Ilias Apalodimas > > > > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h > > index bb8c6f5f19bc..c3a6e6209600 100644 > > --- a/include/linux/mm_types.h > > +++ b/include/linux/mm_types.h > > @@ -105,7 +105,18 @@ struct page { > > struct page_pool *pp; > > unsigned long _pp_mapping_pad; > > unsigned long dma_addr; > > - atomic_long_t pp_frag_count; > > + union { > > + /** > > + * dma_addr_upper: might require a 64-bit > > + * value on 32-bit architectures. > > + */ > > + unsigned long dma_addr_upper; > > + /** > > + * For frag page support, not supported in > > + * 32-bit architectures with 64-bit DMA. > > + */ > > + atomic_long_t pp_frag_count; > > + }; > > }; > > struct { /* slab, slob and slub */ > > union { > > diff --git a/include/net/page_pool.h b/include/net/page_pool.h > > index 3855f069627f..a4082406a003 100644 > > --- a/include/net/page_pool.h > > +++ b/include/net/page_pool.h > > @@ -216,14 +216,24 @@ static inline void page_pool_recycle_direct(struct page_pool *pool, > > page_pool_put_full_page(pool, page, true); > > } > > > > +#define PAGE_POOL_DMA_USE_PP_FRAG_COUNT \ > > + (sizeof(dma_addr_t) > sizeof(unsigned long)) > > + > > static inline dma_addr_t page_pool_get_dma_addr(struct page *page) > > { > > - return page->dma_addr; > > + dma_addr_t ret = page->dma_addr; > > + > > + if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT) > > + ret |= (dma_addr_t)page->dma_addr_upper << 16 << 16; > > + > > + return ret; > > } > > > > static inline void page_pool_set_dma_addr(struct page *page, dma_addr_t addr) > > { > > page->dma_addr = addr; > > + if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT) > > + page->dma_addr_upper = upper_32_bits(addr); > > } > > > > static inline void page_pool_set_frag_count(struct page *page, long nr) > > diff --git a/net/core/page_pool.c b/net/core/page_pool.c > > index 9b60e4301a44..1a6978427d6c 100644 > > --- a/net/core/page_pool.c > > +++ b/net/core/page_pool.c > > @@ -49,12 +49,6 @@ static int page_pool_init(struct page_pool *pool, > > * which is the XDP_TX use-case. > > */ > > if (pool->p.flags & PP_FLAG_DMA_MAP) { > > - /* DMA-mapping is not supported on 32-bit systems with > > - * 64-bit DMA mapping. > > - */ > > - if (sizeof(dma_addr_t) > sizeof(unsigned long)) > > - return -EOPNOTSUPP; > > - > > if ((pool->p.dma_dir != DMA_FROM_DEVICE) && > > (pool->p.dma_dir != DMA_BIDIRECTIONAL)) > > return -EINVAL; > > @@ -75,6 +69,10 @@ static int page_pool_init(struct page_pool *pool, > > */ > > } > > > > + if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT && > > + pool->p.flags & PP_FLAG_PAGE_FRAG) > > + return -EINVAL; > > + > > if (ptr_ring_init(&pool->ring, ring_qsize, GFP_KERNEL) < 0) > > return -ENOMEM; > > > > >