diff options
Diffstat (limited to 'kernel/dma')
| -rw-r--r-- | kernel/dma/Kconfig | 13 | ||||
| -rw-r--r-- | kernel/dma/swiotlb.c | 13 |
2 files changed, 26 insertions, 0 deletions
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig index 562463fe30ea..4c1e9a3c0ab6 100644 --- a/kernel/dma/Kconfig +++ b/kernel/dma/Kconfig @@ -90,6 +90,19 @@ config SWIOTLB bool select NEED_DMA_MAP_STATE +config SWIOTLB_DYNAMIC + bool "Dynamic allocation of DMA bounce buffers" + default n + depends on SWIOTLB + help + This enables dynamic resizing of the software IO TLB. The kernel + starts with one memory pool at boot and it will allocate additional + pools as needed. To reduce run-time kernel memory requirements, you + may have to specify a smaller size of the initial pool using + "swiotlb=" on the kernel command line. + + If unsure, say N. + config DMA_BOUNCE_UNALIGNED_KMALLOC bool depends on SWIOTLB diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 6fc2606e014b..767c8fb36a6b 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -330,6 +330,11 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags, io_tlb_default_mem.force_bounce = swiotlb_force_bounce || (flags & SWIOTLB_FORCE); +#ifdef CONFIG_SWIOTLB_DYNAMIC + if (!remap) + io_tlb_default_mem.can_grow = true; +#endif + if (!default_nareas) swiotlb_adjust_nareas(num_possible_cpus()); @@ -400,6 +405,11 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask, io_tlb_default_mem.force_bounce = swiotlb_force_bounce; +#ifdef CONFIG_SWIOTLB_DYNAMIC + if (!remap) + io_tlb_default_mem.can_grow = true; +#endif + if (!default_nareas) swiotlb_adjust_nareas(num_possible_cpus()); @@ -1073,6 +1083,9 @@ bool is_swiotlb_active(struct device *dev) */ phys_addr_t default_swiotlb_base(void) { +#ifdef CONFIG_SWIOTLB_DYNAMIC + io_tlb_default_mem.can_grow = false; +#endif return io_tlb_default_mem.defpool.start; } |