| Message ID | 20171229081911.2802-28-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Christoph, On Fri, Dec 29, 2017 at 9:18 AM, Christoph Hellwig <hch@lst.de> wrote: > Roughly based on the x86 pci-nommu implementation. > > Signed-off-by: Christoph Hellwig <hch@lst.de> Thanks for your patch! > --- a/lib/dma-direct.c > +++ b/lib/dma-direct.c > @@ -9,6 +9,24 @@ > #include <linux/scatterlist.h> > #include <linux/pfn.h> > > +#define DIRECT_MAPPING_ERROR 0 > + > +static bool > +check_addr(struct device *dev, dma_addr_t dma_addr, size_t size, > + const char *caller) > +{ > + if (unlikely(dev && !dma_capable(dev, dma_addr, size))) { > + if (*dev->dma_mask >= DMA_BIT_MASK(32)) { > + dev_err(dev, > + "%s: overflow %llx+%zu of device mask %llx\n", Please use "%pad" to format dma_addr_t ... > + caller, (long long)dma_addr, size, ... and use &dma_addr. > + (long long)*dev->dma_mask); This cast is not needed, as u64 is unsigned long long in kernelspace on all architectures. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-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
On Fri, Dec 29, 2017 at 03:12:25PM +0100, Geert Uytterhoeven wrote: > > +check_addr(struct device *dev, dma_addr_t dma_addr, size_t size, > > + const char *caller) > > +{ > > + if (unlikely(dev && !dma_capable(dev, dma_addr, size))) { > > + if (*dev->dma_mask >= DMA_BIT_MASK(32)) { > > + dev_err(dev, > > + "%s: overflow %llx+%zu of device mask %llx\n", > > Please use "%pad" to format dma_addr_t ... > > > + caller, (long long)dma_addr, size, > > ... and use &dma_addr. > > > + (long long)*dev->dma_mask); > > This cast is not needed, as u64 is unsigned long long in kernelspace on > all architectures. Thanks, fixed.
diff --git a/lib/dma-direct.c b/lib/dma-direct.c index 0e087650e86b..ddd9dcf4e663 100644 --- a/lib/dma-direct.c +++ b/lib/dma-direct.c @@ -9,6 +9,24 @@ #include <linux/scatterlist.h> #include <linux/pfn.h> +#define DIRECT_MAPPING_ERROR 0 + +static bool +check_addr(struct device *dev, dma_addr_t dma_addr, size_t size, + const char *caller) +{ + if (unlikely(dev && !dma_capable(dev, dma_addr, size))) { + if (*dev->dma_mask >= DMA_BIT_MASK(32)) { + dev_err(dev, + "%s: overflow %llx+%zu of device mask %llx\n", + caller, (long long)dma_addr, size, + (long long)*dev->dma_mask); + } + return false; + } + return true; +} + static void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { @@ -31,7 +49,11 @@ static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, unsigned long attrs) { - return phys_to_dma(dev, page_to_phys(page)) + offset; + dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset; + + if (!check_addr(dev, dma_addr, size, __func__)) + return DIRECT_MAPPING_ERROR; + return dma_addr; } static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, @@ -44,17 +66,25 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, BUG_ON(!sg_page(sg)); sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg)); + if (!check_addr(dev, sg_dma_address(sg), sg->length, __func__)) + return 0; sg_dma_len(sg) = sg->length; } return nents; } +static int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + return dma_addr == DIRECT_MAPPING_ERROR; +} + const struct dma_map_ops dma_direct_ops = { .alloc = dma_direct_alloc, .free = dma_direct_free, .map_page = dma_direct_map_page, .map_sg = dma_direct_map_sg, + .mapping_error = dma_direct_mapping_error, .is_phys = true, }; EXPORT_SYMBOL(dma_direct_ops);
Roughly based on the x86 pci-nommu implementation. Signed-off-by: Christoph Hellwig <hch@lst.de> --- lib/dma-direct.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-)