lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <CAMuHMdXonOxTT7OuTtmyYR346F569aQE0ErhAx8qfsGxWUp+Sg@mail.gmail.com> Date: Tue, 17 Oct 2023 10:43:19 +0200 From: Geert Uytterhoeven <geert@...ux-m68k.org> To: Christoph Hellwig <hch@....de> Cc: Greg Ungerer <gerg@...ux-m68k.org>, iommu@...ts.linux.dev, Paul Walmsley <paul.walmsley@...ive.com>, Palmer Dabbelt <palmer@...belt.com>, Conor Dooley <conor@...nel.org>, Geert Uytterhoeven <geert+renesas@...der.be>, Magnus Damm <magnus.damm@...il.com>, Robin Murphy <robin.murphy@....com>, Marek Szyprowski <m.szyprowski@...sung.com>, Wei Fang <wei.fang@....com>, Shenwei Wang <shenwei.wang@....com>, Clark Wang <xiaoning.wang@....com>, NXP Linux Team <linux-imx@....com>, linux-m68k@...ts.linux-m68k.org, netdev@...r.kernel.org, linux-riscv@...ts.infradead.org, linux-renesas-soc@...r.kernel.org, Jim Quinlan <james.quinlan@...adcom.com> Subject: Re: [PATCH 10/12] net: fec: use dma_alloc_noncoherent for data cache enabled coldfire Hi Christoph, On Mon, Oct 16, 2023 at 7:48 AM Christoph Hellwig <hch@....de> wrote: > Coldfire platforms with data caches can't properly implement > dma_alloc_coherent and currently just return noncoherent memory from > dma_alloc_coherent. > > The fec driver than works around this with a flush of all caches in the > receive path. Make this hack a little less bad by using the explicit > dma_alloc_noncoherent API and documenting the hacky cache flushes so > that the DMA API level hack can be removed. > > Also replace the check for CONFIG_M532x for said hack with a check > for COLDFIRE && !COLDFIRE_COHERENT_DMA. While m532x is the only such > platform with a fec module, this makes the code more consistent and > easier to follow. > > Signed-off-by: Christoph Hellwig <hch@....de> Thanks for your patch! > --- a/drivers/net/ethernet/freescale/fec_main.c > +++ b/drivers/net/ethernet/freescale/fec_main.c > @@ -406,6 +406,70 @@ static void fec_dump(struct net_device *ndev) > } while (bdp != txq->bd.base); > } > > +/* > + * Coldfire does not support DMA coherent allocations, and has historically used > + * a band-aid with a manual flush in fec_enet_rx_queue. > + */ > +#if defined(CONFIG_COLDFIRE) && !defined(CONFIG_COLDFIRE_COHERENT_DMA) > +static void *fec_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, > + gfp_t gfp) > +{ > + return dma_alloc_noncoherent(dev, size, handle, DMA_BIDIRECTIONAL, gfp); > +} > + > +static void fec_dma_free(struct device *dev, size_t size, void *cpu_addr, > + dma_addr_t handle) > +{ > + dma_free_noncoherent(dev, size, cpu_addr, handle, DMA_BIDIRECTIONAL); > +} > +#else /* CONFIG_COLDFIRE && !CONFIG_COLDFIRE_COHERENT_DMA */ !CONFIG_COLDFIRE || CONFIG_COLDFIRE_COHERENT_DMA > +static void *fec_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, > + gfp_t gfp) > +{ > + return dma_alloc_coherent(dev, size, handle, gfp); > +} > + > +static void fec_dma_free(struct device *dev, size_t size, void *cpu_addr, > + dma_addr_t handle) > +{ > + dma_free_coherent(dev, size, cpu_addr, handle); > +} > +#endif /* !CONFIG_COLDFIRE && !CONFIG_COLDFIRE_COHERENT_DMA */ !CONFIG_COLDFIRE || CONFIG_COLDFIRE_COHERENT_DMA Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@...ux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
Powered by blists - more mailing lists