diff options
Diffstat (limited to 'kernel/dma/mapping.c')
| -rw-r--r-- | kernel/dma/mapping.c | 43 |
1 files changed, 35 insertions, 8 deletions
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index cda127027e48..107e4a4d251d 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -443,6 +443,24 @@ bool __dma_need_sync(struct device *dev, dma_addr_t dma_addr) } EXPORT_SYMBOL_GPL(__dma_need_sync); +/** + * dma_need_unmap - does this device need dma_unmap_* operations + * @dev: device to check + * + * If this function returns %false, drivers can skip calling dma_unmap_* after + * finishing an I/O. This function must be called after all mappings that might + * need to be unmapped have been performed. + */ +bool dma_need_unmap(struct device *dev) +{ + if (!dma_map_direct(dev, get_dma_ops(dev))) + return true; + if (!dev->dma_skip_sync) + return true; + return IS_ENABLED(CONFIG_DMA_API_DEBUG); +} +EXPORT_SYMBOL_GPL(dma_need_unmap); + static void dma_setup_need_sync(struct device *dev) { const struct dma_map_ops *ops = get_dma_ops(dev); @@ -910,6 +928,19 @@ int dma_set_coherent_mask(struct device *dev, u64 mask) } EXPORT_SYMBOL(dma_set_coherent_mask); +static bool __dma_addressing_limited(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) < + dma_get_required_mask(dev)) + return true; + + if (unlikely(ops) || use_dma_iommu(dev)) + return false; + return !dma_direct_all_ram_mapped(dev); +} + /** * dma_addressing_limited - return if the device is addressing limited * @dev: device to check @@ -920,15 +951,11 @@ EXPORT_SYMBOL(dma_set_coherent_mask); */ bool dma_addressing_limited(struct device *dev) { - const struct dma_map_ops *ops = get_dma_ops(dev); - - if (min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) < - dma_get_required_mask(dev)) - return true; - - if (unlikely(ops) || use_dma_iommu(dev)) + if (!__dma_addressing_limited(dev)) return false; - return !dma_direct_all_ram_mapped(dev); + + dev_dbg(dev, "device is DMA addressing limited\n"); + return true; } EXPORT_SYMBOL_GPL(dma_addressing_limited); |