Messages in this thread | | | Date | Tue, 10 Sep 2019 11:15:44 -0400 | From | Konrad Rzeszutek Wilk <> | Subject | Re: [PATCH v9 1/5] swiotlb: Split size parameter to map/unmap APIs |
| |
On Fri, Sep 06, 2019 at 02:14:48PM +0800, Lu Baolu wrote: > This splits the size parameter to swiotlb_tbl_map_single() and > swiotlb_tbl_unmap_single() into an alloc_size and a mapping_size > parameter, where the latter one is rounded up to the iommu page > size.
It does a bit more too. You have the WARN_ON. Can you make it be more verbose (as in details of which device requested it) and also use printk_once or so please? > > Suggested-by: Christoph Hellwig <hch@lst.de> > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> > Reviewed-by: Christoph Hellwig <hch@lst.de> > --- > drivers/xen/swiotlb-xen.c | 8 ++++---- > include/linux/swiotlb.h | 8 ++++++-- > kernel/dma/direct.c | 2 +- > kernel/dma/swiotlb.c | 30 +++++++++++++++++++----------- > 4 files changed, 30 insertions(+), 18 deletions(-) > > diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c > index ae1df496bf38..adcabd9473eb 100644 > --- a/drivers/xen/swiotlb-xen.c > +++ b/drivers/xen/swiotlb-xen.c > @@ -386,8 +386,8 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, > */ > trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); > > - map = swiotlb_tbl_map_single(dev, start_dma_addr, phys, size, dir, > - attrs); > + map = swiotlb_tbl_map_single(dev, start_dma_addr, phys, > + size, size, dir, attrs); > if (map == (phys_addr_t)DMA_MAPPING_ERROR) > return DMA_MAPPING_ERROR; > > @@ -397,7 +397,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, > * Ensure that the address returned is DMA'ble > */ > if (unlikely(!dma_capable(dev, dev_addr, size))) { > - swiotlb_tbl_unmap_single(dev, map, size, dir, > + swiotlb_tbl_unmap_single(dev, map, size, size, dir, > attrs | DMA_ATTR_SKIP_CPU_SYNC); > return DMA_MAPPING_ERROR; > } > @@ -433,7 +433,7 @@ static void xen_unmap_single(struct device *hwdev, dma_addr_t dev_addr, > > /* NOTE: We use dev_addr here, not paddr! */ > if (is_xen_swiotlb_buffer(dev_addr)) > - swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs); > + swiotlb_tbl_unmap_single(hwdev, paddr, size, size, dir, attrs); > } > > static void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, > diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h > index 361f62bb4a8e..cde3dc18e21a 100644 > --- a/include/linux/swiotlb.h > +++ b/include/linux/swiotlb.h > @@ -46,13 +46,17 @@ enum dma_sync_target { > > extern phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > dma_addr_t tbl_dma_addr, > - phys_addr_t phys, size_t size, > + phys_addr_t phys, > + size_t mapping_size, > + size_t alloc_size, > enum dma_data_direction dir, > unsigned long attrs); > > extern void swiotlb_tbl_unmap_single(struct device *hwdev, > phys_addr_t tlb_addr, > - size_t size, enum dma_data_direction dir, > + size_t mapping_size, > + size_t alloc_size, > + enum dma_data_direction dir, > unsigned long attrs); > > extern void swiotlb_tbl_sync_single(struct device *hwdev, > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index 706113c6bebc..8402b29c280f 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -305,7 +305,7 @@ void dma_direct_unmap_page(struct device *dev, dma_addr_t addr, > dma_direct_sync_single_for_cpu(dev, addr, size, dir); > > if (unlikely(is_swiotlb_buffer(phys))) > - swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); > + swiotlb_tbl_unmap_single(dev, phys, size, size, dir, attrs); > } > EXPORT_SYMBOL(dma_direct_unmap_page); > > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c > index 9de232229063..89066efa3840 100644 > --- a/kernel/dma/swiotlb.c > +++ b/kernel/dma/swiotlb.c > @@ -444,7 +444,9 @@ static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr, > > phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > dma_addr_t tbl_dma_addr, > - phys_addr_t orig_addr, size_t size, > + phys_addr_t orig_addr, > + size_t mapping_size, > + size_t alloc_size, > enum dma_data_direction dir, > unsigned long attrs) > { > @@ -464,6 +466,9 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > pr_warn_once("%s is active and system is using DMA bounce buffers\n", > sme_active() ? "SME" : "SEV"); > > + if (WARN_ON(mapping_size > alloc_size)) > + return (phys_addr_t)DMA_MAPPING_ERROR; > + > mask = dma_get_seg_boundary(hwdev); > > tbl_dma_addr &= mask; > @@ -481,8 +486,8 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > * For mappings greater than or equal to a page, we limit the stride > * (and hence alignment) to a page size. > */ > - nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; > - if (size >= PAGE_SIZE) > + nslots = ALIGN(alloc_size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; > + if (alloc_size >= PAGE_SIZE) > stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); > else > stride = 1; > @@ -547,7 +552,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > spin_unlock_irqrestore(&io_tlb_lock, flags); > if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) > dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n", > - size, io_tlb_nslabs, tmp_io_tlb_used); > + alloc_size, io_tlb_nslabs, tmp_io_tlb_used); > return (phys_addr_t)DMA_MAPPING_ERROR; > found: > io_tlb_used += nslots; > @@ -562,7 +567,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT); > if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && > (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) > - swiotlb_bounce(orig_addr, tlb_addr, size, DMA_TO_DEVICE); > + swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE); > > return tlb_addr; > } > @@ -571,21 +576,24 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > * tlb_addr is the physical address of the bounce buffer to unmap. > */ > void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, > - size_t size, enum dma_data_direction dir, > - unsigned long attrs) > + size_t mapping_size, size_t alloc_size, > + enum dma_data_direction dir, unsigned long attrs) > { > unsigned long flags; > - int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; > + int i, count, nslots = ALIGN(alloc_size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; > int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; > phys_addr_t orig_addr = io_tlb_orig_addr[index]; > > + if (WARN_ON(mapping_size > alloc_size)) > + return; > + > /* > * First, sync the memory before unmapping the entry > */ > if (orig_addr != INVALID_PHYS_ADDR && > !(attrs & DMA_ATTR_SKIP_CPU_SYNC) && > ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL))) > - swiotlb_bounce(orig_addr, tlb_addr, size, DMA_FROM_DEVICE); > + swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_FROM_DEVICE); > > /* > * Return the buffer to the free list by setting the corresponding > @@ -665,14 +673,14 @@ bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr, > > /* Oh well, have to allocate and map a bounce buffer. */ > *phys = swiotlb_tbl_map_single(dev, __phys_to_dma(dev, io_tlb_start), > - *phys, size, dir, attrs); > + *phys, size, size, dir, attrs); > if (*phys == (phys_addr_t)DMA_MAPPING_ERROR) > return false; > > /* Ensure that the address returned is DMA'ble */ > *dma_addr = __phys_to_dma(dev, *phys); > if (unlikely(!dma_capable(dev, *dma_addr, size))) { > - swiotlb_tbl_unmap_single(dev, *phys, size, dir, > + swiotlb_tbl_unmap_single(dev, *phys, size, size, dir, > attrs | DMA_ATTR_SKIP_CPU_SYNC); > return false; > } > -- > 2.17.1 >
| |