From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752222AbdGETgo (ORCPT ); Wed, 5 Jul 2017 15:36:44 -0400 Received: from mout.gmx.net ([212.227.17.20]:63924 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751664AbdGETgm (ORCPT ); Wed, 5 Jul 2017 15:36:42 -0400 Subject: Re: [PATCH] parisc: DMA API: return error instead of BUG_ON for dma ops on non dma devs To: Christoph Hellwig Cc: Thomas Bogendoerfer , jejb@parisc-linux.org, linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20170703084920.142A9508094@solo.franken.de> <83ff44f5-8989-c806-bef3-29fb9c909bee@gmx.de> <20170705185756.GA18087@infradead.org> From: Helge Deller Message-ID: <9de25038-5a0e-697d-dfb4-b6eb65189079@gmx.de> Date: Wed, 5 Jul 2017 21:36:09 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20170705185756.GA18087@infradead.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:BV5HpiBrPe6BHYlZNutgTOWMC0qffmudxt7D3wT6BYZG7nJFg7v e5ZHXyDA124rFdKP6Ya+foVRDThGz3bQGX7iiFgnaGJpZhzKA8VceDGDYEQW0piFMTKYHU6 cOQA7+z86xU5ypO4i3292D9rEixVPIwO99M0YG6mappP4PARl27qiL0hLqwcYhXlZSDBL/9 x2JbgV1fvQZhOJdvXXxSw== X-UI-Out-Filterresults: notjunk:1;V01:K0:vZL+4knFtr4=:rOPVtsCsdUlOcRHL98lD81 1g8ETM4k+Jrdv/aOBmfnWnVtcJOYi1UrXorP/j85P6h/rI/uYvyy7HtxKAdB66HFczForx6Bd NING5ieKBU6ktvWotMggIM79ase4pkGvrSZ5YLMEK33sM4xIoY7D8q62zIwIfNrwJUkAzCoVQ yux6ynbfJAX2AZweSLQiLz5kNr+KbZp0rp4GNQ/o8MJTnOSMKi3MXwdIleN/PIUDiHzU5E3L+ G0AIhiJg7LXr1o41x2QqxvEvFpN573IkcwTRhL29DLINVpHyYr+6Bl9Y3KN5GQxWbk9OEUmQw mGX19aKWeh7iWT4ZfU5w+Bdv1w7ktSLuBut65wHW0JidH3QlIqWrJZfkBhpFfF6NzmQFJoH+w FSjjfftc9liYpiHjzYrkmpMuahChqG+ZyK4fa6gm9yUmLSMSTlPZJ2WwE1P+W0byzLdH7KvOo +QAjzE54oW36k1p5AYpzx1Xt1FoDfnr2yisZMhXJ8a8oNK6uo+cnG1aviYPz2iFG+KdYNC3IQ WP3KszVs5MfgDyUC3MnVsCezSe9vMyPaF7LFBuJkscbDGYxoS8XP3gDUgLmL5PNQ0CXGhv6qF hUj8QhgjhN9h31JL/pNCHOZq9w2Jk42ZNkFAVdeStlGQoYuZjS0PLz7h+9bl1dksvc28V7WhZ vjFMCMhgBf/CXWZb3ltIVSLDrspxAiV+pSTT0m/2vUF7J8/9dTcoJlYSNXi6fMDtPolwpE11O kMckM56Tbeza6v9tPsHU2fFBQs7IzViRJBumpLTomLgPke9l84RUTH1gGoLcRDlz7kpmqeD4q DF0KF+u Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Christoph, On 05.07.2017 20:57, Christoph Hellwig wrote: > I've got a tree pending that removes DMA_ERROR_CODE, and it's been > in linux-next for a while. I had the parisc patch in for-next as well and didn't received any warnings. > While this won't compile-time conflict with this patch and will > basically revert the effect. > > Can you please test the patch below and send it to Linus ASAP so that > I can send the pull request for the dma-mapping tree? I'll do that now. > --- > From 85942d54e2f0ad5f4b4e074ce2e271be17b31274 Mon Sep 17 00:00:00 2001 > From: Christoph Hellwig > Date: Tue, 4 Jul 2017 19:55:06 -0700 > Subject: parisc: ->mapping_error > > DMA_ERROR_CODE already went away in linux-next, but parisc unfortunately > added a new instance of it without any review as far as I can tell. Can we please change this to something like "Prepare parisc to get rid of DMA_ERROR_CODE tree-wide" ? It's somewhat more neutral. Helge > > Move the two iommu drivers to report errors through ->mapping_error. > > Signed-off-by: Christoph Hellwig > --- > arch/parisc/include/asm/dma-mapping.h | 2 -- > drivers/parisc/ccio-dma.c | 10 +++++++++- > drivers/parisc/sba_iommu.c | 10 +++++++++- > 3 files changed, 18 insertions(+), 4 deletions(-) > > diff --git a/arch/parisc/include/asm/dma-mapping.h b/arch/parisc/include/asm/dma-mapping.h > index 9a2a8956a695..2b16282add69 100644 > --- a/arch/parisc/include/asm/dma-mapping.h > +++ b/arch/parisc/include/asm/dma-mapping.h > @@ -20,8 +20,6 @@ > ** flush/purge and allocate "regular" cacheable pages for everything. > */ > > -#define DMA_ERROR_CODE (~(dma_addr_t)0) > - > #ifdef CONFIG_PA11 > extern const struct dma_map_ops pcxl_dma_ops; > extern const struct dma_map_ops pcx_dma_ops; > diff --git a/drivers/parisc/ccio-dma.c b/drivers/parisc/ccio-dma.c > index 56c93f096de9..6aa1e7f6672f 100644 > --- a/drivers/parisc/ccio-dma.c > +++ b/drivers/parisc/ccio-dma.c > @@ -110,6 +110,8 @@ > #define CMD_TLB_DIRECT_WRITE 35 /* IO_COMMAND for I/O TLB Writes */ > #define CMD_TLB_PURGE 33 /* IO_COMMAND to Purge I/O TLB entry */ > > +#define CCIO_MAPPING_ERROR (~(dma_addr_t)0) > + > struct ioa_registers { > /* Runway Supervisory Set */ > int32_t unused1[12]; > @@ -742,7 +744,7 @@ ccio_map_single(struct device *dev, void *addr, size_t size, > BUG_ON(!dev); > ioc = GET_IOC(dev); > if (!ioc) > - return DMA_ERROR_CODE; > + return CCIO_MAPPING_ERROR; > > BUG_ON(size <= 0); > > @@ -1023,6 +1025,11 @@ ccio_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, > DBG_RUN_SG("%s() DONE (nents %d)\n", __func__, nents); > } > > +static int ccio_mapping_error(struct device *dev, dma_addr_t dma_addr) > +{ > + return dma_addr == CCIO_MAPPING_ERROR; > +} > + > static const struct dma_map_ops ccio_ops = { > .dma_supported = ccio_dma_supported, > .alloc = ccio_alloc, > @@ -1031,6 +1038,7 @@ static const struct dma_map_ops ccio_ops = { > .unmap_page = ccio_unmap_page, > .map_sg = ccio_map_sg, > .unmap_sg = ccio_unmap_sg, > + .mapping_error = ccio_mapping_error, > }; > > #ifdef CONFIG_PROC_FS > diff --git a/drivers/parisc/sba_iommu.c b/drivers/parisc/sba_iommu.c > index 87ad5fd6a7a2..4086f79d58d5 100644 > --- a/drivers/parisc/sba_iommu.c > +++ b/drivers/parisc/sba_iommu.c > @@ -93,6 +93,8 @@ > > #define DEFAULT_DMA_HINT_REG 0 > > +#define SBA_MAPPING_ERROR (~(dma_addr_t)0) > + > struct sba_device *sba_list; > EXPORT_SYMBOL_GPL(sba_list); > > @@ -725,7 +727,7 @@ sba_map_single(struct device *dev, void *addr, size_t size, > > ioc = GET_IOC(dev); > if (!ioc) > - return DMA_ERROR_CODE; > + return SBA_MAPPING_ERROR; > > /* save offset bits */ > offset = ((dma_addr_t) (long) addr) & ~IOVP_MASK; > @@ -1083,6 +1085,11 @@ sba_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, > > } > > +static int sba_mapping_error(struct device *dev, dma_addr_t dma_addr) > +{ > + return dma_addr == SBA_MAPPING_ERROR; > +} > + > static const struct dma_map_ops sba_ops = { > .dma_supported = sba_dma_supported, > .alloc = sba_alloc, > @@ -1091,6 +1098,7 @@ static const struct dma_map_ops sba_ops = { > .unmap_page = sba_unmap_page, > .map_sg = sba_map_sg, > .unmap_sg = sba_unmap_sg, > + .mapping_error = sba_mapping_error, > }; > > >