ARM: dma-mapping: add support for CMA regions placed in highmem zone
This patch adds missing pieces to correctly support memory pages served
from CMA regions placed in high memory zones. Please note that the default
global CMA area is still put into lowmem and is limited by optional
architecture specific DMA zone. One can however put device specific CMA
regions in high memory zone to reduce lowmem usage.
Change-Id: I92ae4a772f24e0ca90c5560a826207850618b506
CRs-Fixed: 467034
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
[lauraa@codeaurora.org: Context fixups]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 41fef00..1957b4a 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -165,16 +165,29 @@
static void __dma_clear_buffer(struct page *page, size_t size)
{
- void *ptr;
/*
* Ensure that the allocated pages are zeroed, and that any data
* lurking in the kernel direct-mapped region is invalidated.
*/
- ptr = page_address(page);
- if (ptr) {
- memset(ptr, 0, size);
- dmac_flush_range(ptr, ptr + size);
- outer_flush_range(__pa(ptr), __pa(ptr) + size);
+ if (!PageHighMem(page)) {
+ void *ptr = page_address(page);
+ if (ptr) {
+ memset(ptr, 0, size);
+ dmac_flush_range(ptr, ptr + size);
+ outer_flush_range(__pa(ptr), __pa(ptr) + size);
+ }
+ } else {
+ phys_addr_t base = __pfn_to_phys(page_to_pfn(page));
+ phys_addr_t end = base + size;
+ while (size > 0) {
+ void *ptr = kmap_atomic(page);
+ memset(ptr, 0, PAGE_SIZE);
+ dmac_flush_range(ptr, ptr + PAGE_SIZE);
+ kunmap_atomic(ptr);
+ page++;
+ size -= PAGE_SIZE;
+ }
+ outer_flush_range(base, end);
}
}
@@ -315,7 +328,7 @@
static void *__alloc_from_contiguous(struct device *dev, size_t size,
pgprot_t prot, struct page **ret_page,
- bool no_kernel_mapping);
+ bool no_kernel_mapping, const void *caller);
static struct arm_vmregion_head coherent_head = {
.vm_lock = __SPIN_LOCK_UNLOCKED(&coherent_head.vm_lock),
@@ -344,7 +357,8 @@
if (!IS_ENABLED(CONFIG_CMA))
return 0;
- ptr = __alloc_from_contiguous(NULL, size, prot, &page, false);
+ ptr = __alloc_from_contiguous(NULL, size, prot, &page, false,
+ coherent_init);
if (ptr) {
coherent_head.vm_start = (unsigned long) ptr;
coherent_head.vm_end = (unsigned long) ptr + size;
@@ -621,27 +635,41 @@
static void *__alloc_from_contiguous(struct device *dev, size_t size,
pgprot_t prot, struct page **ret_page,
- bool no_kernel_mapping)
+ bool no_kernel_mapping,
+ const void *caller)
{
unsigned long order = get_order(size);
size_t count = size >> PAGE_SHIFT;
struct page *page;
+ void *ptr;
page = dma_alloc_from_contiguous(dev, count, order);
if (!page)
return NULL;
__dma_clear_buffer(page, size);
- __dma_remap(page, size, prot, no_kernel_mapping);
+ if (!PageHighMem(page)) {
+ __dma_remap(page, size, prot, no_kernel_mapping);
+ ptr = page_address(page);
+ } else {
+ ptr = __dma_alloc_remap(page, size, GFP_KERNEL, prot, caller);
+ if (!ptr) {
+ dma_release_from_contiguous(dev, page, count);
+ return NULL;
+ }
+ }
*ret_page = page;
- return page_address(page);
+ return ptr;
}
static void __free_from_contiguous(struct device *dev, struct page *page,
- size_t size)
+ void *cpu_addr, size_t size)
{
- __dma_remap(page, size, pgprot_kernel, false);
+ if (!PageHighMem(page))
+ __dma_remap(page, size, pgprot_kernel, false);
+ else
+ __dma_free_remap(cpu_addr, size);
dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT);
}
@@ -731,7 +759,7 @@
addr = __alloc_from_pool(dev, size, &page, caller);
else
addr = __alloc_from_contiguous(dev, size, prot, &page,
- no_kernel_mapping);
+ no_kernel_mapping, caller);
if (addr)
*handle = pfn_to_dma(dev, page_to_pfn(page));
@@ -807,7 +835,7 @@
* Non-atomic allocations cannot be freed with IRQs disabled
*/
WARN_ON(irqs_disabled());
- __free_from_contiguous(dev, page, size);
+ __free_from_contiguous(dev, page, cpu_addr, size);
}
}