On Thu, Aug 21 2014, Marek Szyprowski m.szyprowski@samsung.com wrote:
Automatically allocated regions should not cross low/high memory boundary, because such regions cannot be later correctly initialized due to spanning across two memory zones. This patch adds a check for this case and a simple code for moving region to low memory if automatically selected address might not fit completely into high memory.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com
Acked-by: Michal Nazarewicz mina86@mina86.com
mm/cma.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)
diff --git a/mm/cma.c b/mm/cma.c index c17751c0dcaf..4acc6aa4a086 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -32,6 +32,7 @@ #include <linux/slab.h> #include <linux/log2.h> #include <linux/cma.h> +#include <linux/highmem.h> struct cma { unsigned long base_pfn; @@ -163,6 +164,8 @@ int __init cma_declare_contiguous(phys_addr_t base, bool fixed, struct cma **res_cma) { struct cma *cma;
- phys_addr_t memblock_end = memblock_end_of_DRAM();
- phys_addr_t highmem_start = __pa(high_memory); int ret = 0;
pr_debug("%s(size %lx, base %08lx, limit %08lx alignment %08lx)\n", @@ -196,6 +199,24 @@ int __init cma_declare_contiguous(phys_addr_t base, if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit)) return -EINVAL;
- /*
* adjust limit to avoid crossing low/high memory boundary for* automatically allocated regions*/- if (((limit == 0 || limit > memblock_end) &&
(memblock_end - size < highmem_start &&memblock_end > highmem_start)) ||(!fixed && limit > highmem_start && limit - size < highmem_start)) {limit = highmem_start;- }
- if (fixed && base < highmem_start && base+size > highmem_start) {
ret = -EINVAL;pr_err("Region at %08lx defined on low/high memory boundary (%08lx)\n",(unsigned long)base, (unsigned long)highmem_start);goto err;- }
- /* Reserve memory */ if (base && fixed) { if (memblock_is_region_reserved(base, size) ||
-- 1.9.2