On Wed, Feb 29, 2012 at 04:04:22PM +0100, Marek Szyprowski wrote:

quoted

+static int arm_iommu_mmap_attrs(struct device *dev, struct

vm_area_struct *vma,

quoted

+		    void *cpu_addr, dma_addr_t dma_addr, size_t size,
+		    struct dma_attrs *attrs)
+{
+	struct arm_vmregion *c;
+
+	vma->vm_page_prot = __get_dma_pgprot(attrs, vma-
vm_page_prot);
+	c = arm_vmregion_find(&consistent_head, (unsigned

long)cpu_addr);

What protects this against other insertions/removals from the list?

arm_vmregion_find uses a spin_lock internally before accessing consistent_head.
 So, it is protected.


-KR

--nvpublic