From patchwork Thu Jul 9 16:19:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 1270431 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CCE41C433E1 for ; Thu, 9 Jul 2020 16:19:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A45E6207D0 for ; Thu, 9 Jul 2020 16:19:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728194AbgGIQTf (ORCPT ); Thu, 9 Jul 2020 12:19:35 -0400 Received: from mx2.suse.de ([195.135.220.15]:39104 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726357AbgGIQTd (ORCPT ); Thu, 9 Jul 2020 12:19:33 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 7ADF6AEC4; Thu, 9 Jul 2020 16:19:32 +0000 (UTC) From: Nicolas Saenz Julienne To: hch@lst.de, Robin Murphy , David Rientjes , iommu@lists.linux-foundation.org, Marek Szyprowski Cc: linux-rpi-kernel@lists.infradead.org, jeremy.linton@arm.com, Nicolas Saenz Julienne , linux-kernel@vger.kernel.org Subject: [PATCH 1/4] dma-direct: Provide function to check physical memory area validity Date: Thu, 9 Jul 2020 18:19:01 +0200 Message-Id: <20200709161903.26229-2-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200709161903.26229-1-nsaenzjulienne@suse.de> References: <20200709161903.26229-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org dma_coherent_ok() checks if a physical memory area fits a device's DMA constraints. Signed-off-by: Nicolas Saenz Julienne --- include/linux/dma-direct.h | 1 + kernel/dma/direct.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h index cdfa400f89b3..cb23a8305132 100644 --- a/include/linux/dma-direct.h +++ b/include/linux/dma-direct.h @@ -69,6 +69,7 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size, u64 dma_direct_get_required_mask(struct device *dev); gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, u64 *phys_mask); +bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size); void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 93f578a8e613..4de864cacd22 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -70,7 +70,7 @@ gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, return 0; } -static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) +bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) { return phys_to_dma_direct(dev, phys) + size - 1 <= min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit); From patchwork Thu Jul 9 16:19:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 1270429 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CFFDFC433E1 for ; Thu, 9 Jul 2020 16:19:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B4AEB207D0 for ; Thu, 9 Jul 2020 16:19:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728257AbgGIQTg (ORCPT ); Thu, 9 Jul 2020 12:19:36 -0400 Received: from mx2.suse.de ([195.135.220.15]:39124 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727952AbgGIQTe (ORCPT ); Thu, 9 Jul 2020 12:19:34 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 3B598AEBE; Thu, 9 Jul 2020 16:19:33 +0000 (UTC) From: Nicolas Saenz Julienne To: hch@lst.de, Robin Murphy , David Rientjes , iommu@lists.linux-foundation.org, Marek Szyprowski Cc: linux-rpi-kernel@lists.infradead.org, jeremy.linton@arm.com, Nicolas Saenz Julienne , linux-kernel@vger.kernel.org Subject: [PATCH 2/4] dma-pool: Get rid of dma_in_atomic_pool() Date: Thu, 9 Jul 2020 18:19:02 +0200 Message-Id: <20200709161903.26229-3-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200709161903.26229-1-nsaenzjulienne@suse.de> References: <20200709161903.26229-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function is only used once and can be simplified to a one-liner. Signed-off-by: Nicolas Saenz Julienne --- kernel/dma/pool.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 8cfa01243ed2..7363640fc91c 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -217,15 +217,6 @@ static inline struct gen_pool *dev_to_pool(struct device *dev) return atomic_pool_kernel; } -static bool dma_in_atomic_pool(struct device *dev, void *start, size_t size) -{ - struct gen_pool *pool = dev_to_pool(dev); - - if (unlikely(!pool)) - return false; - return gen_pool_has_addr(pool, (unsigned long)start, size); -} - void *dma_alloc_from_pool(struct device *dev, size_t size, struct page **ret_page, gfp_t flags) { @@ -256,7 +247,7 @@ bool dma_free_from_pool(struct device *dev, void *start, size_t size) { struct gen_pool *pool = dev_to_pool(dev); - if (!dma_in_atomic_pool(dev, start, size)) + if (!pool || !gen_pool_has_addr(pool, (unsigned long)start, size)) return false; gen_pool_free(pool, (unsigned long)start, size); return true; From patchwork Thu Jul 9 16:19:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 1270432 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 896B4C433DF for ; Thu, 9 Jul 2020 16:19:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 66E7F207D0 for ; Thu, 9 Jul 2020 16:19:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728283AbgGIQTo (ORCPT ); Thu, 9 Jul 2020 12:19:44 -0400 Received: from mx2.suse.de ([195.135.220.15]:39146 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728132AbgGIQTg (ORCPT ); Thu, 9 Jul 2020 12:19:36 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id EA3F0AEC8; Thu, 9 Jul 2020 16:19:33 +0000 (UTC) From: Nicolas Saenz Julienne To: hch@lst.de, Robin Murphy , David Rientjes , iommu@lists.linux-foundation.org, Marek Szyprowski Cc: linux-rpi-kernel@lists.infradead.org, jeremy.linton@arm.com, Nicolas Saenz Julienne , linux-kernel@vger.kernel.org Subject: [PATCH 3/4] dma-pool: Introduce dma_guess_pool() Date: Thu, 9 Jul 2020 18:19:03 +0200 Message-Id: <20200709161903.26229-4-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200709161903.26229-1-nsaenzjulienne@suse.de> References: <20200709161903.26229-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org dma-pool's dev_to_pool() creates the false impression that there is a way to grantee a mapping between a device's DMA constraints and an atomic pool. It tuns out it's just a guess, and the device might need to use an atomic pool containing memory from a 'safer' (or lower) memory zone. To help mitigate this, introduce dma_guess_pool() which can be fed a device's DMA constraints or an atomic pool already known to be faulty in order for it to provide a better guess at which pool to use. Signed-off-by: Nicolas Saenz Julienne --- kernel/dma/pool.c | 26 +++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 7363640fc91c..3d518de07617 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -203,7 +203,7 @@ static int __init dma_atomic_pool_init(void) } postcore_initcall(dma_atomic_pool_init); -static inline struct gen_pool *dev_to_pool(struct device *dev) +static inline struct gen_pool *dma_guess_pool_from_device(struct device *dev) { u64 phys_mask; gfp_t gfp; @@ -217,10 +217,30 @@ static inline struct gen_pool *dev_to_pool(struct device *dev) return atomic_pool_kernel; } +static inline struct gen_pool *dma_get_safer_pool(struct gen_pool *bad_pool) +{ + if (bad_pool == atomic_pool_kernel) + return atomic_pool_dma32 ? : atomic_pool_dma; + + if (bad_pool == atomic_pool_dma32) + return atomic_pool_dma; + + return NULL; +} + +static inline struct gen_pool *dma_guess_pool(struct device *dev, + struct gen_pool *bad_pool) +{ + if (bad_pool) + return dma_get_safer_pool(bad_pool); + + return dma_guess_pool_from_device(dev); +} + void *dma_alloc_from_pool(struct device *dev, size_t size, struct page **ret_page, gfp_t flags) { - struct gen_pool *pool = dev_to_pool(dev); + struct gen_pool *pool = dma_guess_pool(dev, NULL); unsigned long val; void *ptr = NULL; @@ -245,7 +265,7 @@ void *dma_alloc_from_pool(struct device *dev, size_t size, bool dma_free_from_pool(struct device *dev, void *start, size_t size) { - struct gen_pool *pool = dev_to_pool(dev); + struct gen_pool *pool = dma_guess_pool(dev, NULL); if (!pool || !gen_pool_has_addr(pool, (unsigned long)start, size)) return false; From patchwork Thu Jul 9 16:19:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 1270430 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23DFAC433DF for ; Thu, 9 Jul 2020 16:19:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F009B207D0 for ; Thu, 9 Jul 2020 16:19:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728269AbgGIQTh (ORCPT ); Thu, 9 Jul 2020 12:19:37 -0400 Received: from mx2.suse.de ([195.135.220.15]:39170 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728239AbgGIQTg (ORCPT ); Thu, 9 Jul 2020 12:19:36 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 9B97DAED2; Thu, 9 Jul 2020 16:19:34 +0000 (UTC) From: Nicolas Saenz Julienne To: hch@lst.de, Robin Murphy , David Rientjes , iommu@lists.linux-foundation.org, Marek Szyprowski Cc: linux-rpi-kernel@lists.infradead.org, jeremy.linton@arm.com, Nicolas Saenz Julienne , linux-kernel@vger.kernel.org Subject: [PATCH 4/4] dma-pool: Make sure atomic pool suits device Date: Thu, 9 Jul 2020 18:19:04 +0200 Message-Id: <20200709161903.26229-5-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200709161903.26229-1-nsaenzjulienne@suse.de> References: <20200709161903.26229-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When allocating DMA memory from a pool, the core can only guess which atomic pool will fit a device's constraints. If it doesn't, get a safer atomic pool and try again. Fixes: c84dc6e68a1d ("dma-pool: add additional coherent pools to map to gfp mask") Reported-by: Jeremy Linton Suggested-by: Robin Murphy Signed-off-by: Nicolas Saenz Julienne --- kernel/dma/pool.c | 53 +++++++++++++++++++++++++++++++++-------------- 1 file changed, 37 insertions(+), 16 deletions(-) diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 3d518de07617..d48d9acb585f 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -240,35 +240,56 @@ static inline struct gen_pool *dma_guess_pool(struct device *dev, void *dma_alloc_from_pool(struct device *dev, size_t size, struct page **ret_page, gfp_t flags) { - struct gen_pool *pool = dma_guess_pool(dev, NULL); - unsigned long val; + struct gen_pool *pool = NULL; + unsigned long val = 0; void *ptr = NULL; - - if (!pool) { - WARN(1, "%pGg atomic pool not initialised!\n", &flags); - return NULL; + phys_addr_t phys; + + while (1) { + pool = dma_guess_pool(dev, pool); + if (!pool) { + WARN(1, "Failed to get suitable pool for %s\n", + dev_name(dev)); + break; + } + + val = gen_pool_alloc(pool, size); + if (!val) + continue; + + phys = gen_pool_virt_to_phys(pool, val); + if (dma_coherent_ok(dev, phys, size)) + break; + + gen_pool_free(pool, val, size); + val = 0; } - val = gen_pool_alloc(pool, size); - if (val) { - phys_addr_t phys = gen_pool_virt_to_phys(pool, val); + if (val) { *ret_page = pfn_to_page(__phys_to_pfn(phys)); ptr = (void *)val; memset(ptr, 0, size); + + if (gen_pool_avail(pool) < atomic_pool_size) + schedule_work(&atomic_pool_work); } - if (gen_pool_avail(pool) < atomic_pool_size) - schedule_work(&atomic_pool_work); return ptr; } bool dma_free_from_pool(struct device *dev, void *start, size_t size) { - struct gen_pool *pool = dma_guess_pool(dev, NULL); + struct gen_pool *pool = NULL; + + while (1) { + pool = dma_guess_pool(dev, pool); + if (!pool) + return false; - if (!pool || !gen_pool_has_addr(pool, (unsigned long)start, size)) - return false; - gen_pool_free(pool, (unsigned long)start, size); - return true; + if (gen_pool_has_addr(pool, (unsigned long)start, size)) { + gen_pool_free(pool, (unsigned long)start, size); + return true; + } + } }