Change Details

When the BUSDMA boundary is non-zero, as for AMD64 due to PCI_DMA_BOUNDARY and the BUSDMA lowaddr is equal to BUS_SPACE_MAXADDR, the bus_dmamem_alloc() function always fall back into using a contiguous allocation even when this is not needed. This patch adds some more conditions where a page based allocation will work. The conditions added basically does the following: If the boundary is divisible into the alignment and the alignment is divisible into the maximum segment size, it is not possible to get a segment which crosses the boundary. Sponsored by: Mellanox Technologies MFC after: 1 week

When the BUSDMA boundary is non-zero, as for AMD64 due to PCI_DMA_BOUNDARY and the BUSDMA lowaddr is equal to BUS_SPACE_MAXADDR, the bus_dmamem_alloc() function always fall back into using a contiguous allocation even when this is not needed. This patch widens the conditions for using kmem_alloc_attr() to also cover more cases where the boundary parameter is non-zero and less than lowaddr. This patch also fixes the nsegments check for using kmem_alloc_attr() when the maximum segment size is less than PAGE_SIZE . Sponsored by: Mellanox Technologies MFC after: 1 week

When the BUSDMA boundary is non-zero, as for AMD64 due to PCI_DMA_BOUNDARY and the BUSDMA lowaddr is equal to BUS_SPACE_MAXADDR, the bus_dmamem_alloc() function always fall back into using a contiguous allocation even when this is not needed. This patch adds some more conditions where a page based allocation will work. The conditions added basically does the following:widens the conditions for using kmem_alloc_attr() to also cover more cases where the boundary parameter is non-zero and less than lowaddr. If the boundary is divisible intoThis patch also fixes the alignnsegment and the alignment is divisible intos check for using kmem_alloc_attr() when the maximum segment size,e is less than PAGE_SIZE it is not possible to get a segment which crosses the boundary. Sponsored by: Mellanox Technologies MFC after: 1 week