Rather than supplying a __weak hook which architectures which support highmem can overide simply provide a version of swiotlb_bus_to_virt which works with high memory. Make it conditional since it is a more expensive variant than the non-highmem version.
Acutal function contents taken from the PowerPC swiotlb patchset by Becky Bruce. Signed-off-by: Ian Campbell <[email protected]> Cc: Becky Bruce <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Kumar Gala <[email protected]> Cc: FUJITA Tomonori <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jeremy Fitzhardinge <[email protected]> Cc: [email protected] --- lib/swiotlb.c | 11 ++++++++++- 1 files changed, 10 insertions(+), 1 deletions(-) diff --git a/lib/swiotlb.c b/lib/swiotlb.c index d37499b..d2b296a 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -130,9 +130,18 @@ static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev, return phys_to_dma(hwdev, virt_to_phys(address)); } -void * __weak swiotlb_bus_to_virt(struct device *hwdev, dma_addr_t address) +static void *swiotlb_bus_to_virt(struct device *hwdev, dma_addr_t address) { +#ifdef CONFIG_HIGHMEM + unsigned long pfn = PFN_DOWN(dma_to_phys(hwdev, address)); + void *pageaddr = page_address(pfn_to_page(pfn)); + + if (pageaddr != NULL) + return pageaddr + (address % PAGE_SIZE); + return NULL; +#else return phys_to_virt(dma_to_phys(hwdev, address)); +#endif } static void swiotlb_print_info(unsigned long bytes) -- 1.5.6.5 _______________________________________________ Linuxppc-dev mailing list [email protected] https://ozlabs.org/mailman/listinfo/linuxppc-dev
