Ion carveout and content protect heap buffers do not
have a struct page associated with them. Thus
sg_phys() will not work reliably on these buffers.
Set the dma_address field on physically contiguous
buffers. When mapping a scatterlist to the gpummu
use sg_dma_address() first and if it returns 0
then use sg_phys().
msm: kgsl: Use kzalloc to allocate scatterlists of 1 page or less
The majority of the scatterlist allocations used in KGSL are under 1
page (1 page of struct scatterlist is approximately 1024 entries
equalling 4MB of allocated buffer). In these cases using vmalloc
for the sglist is undesirable and slow. Add functions to check the
size of the allocation and favor kzalloc for 1 page allocations and
vmalloc for larger lists.
For dma_alloc_coherent() you don't need writel/readl because
it's just a plain old void *. Linux tries very hard to make a
distinction between io memory (void __iomem *) and memory
(void *) so that drivers are portable to architectures that
don't have a way to access registers via pointer dereferences.
You can see http://lwn.net/Articles/102232/ and the Linus rant
http://lwn.net/Articles/102240/ here for more details behind
the motivation.
msm: kgsl: Allocate physical pages instead of using vmalloc
Replace vmalloc allocation with physical page allocation. For most
allocations we do not need a kernel virual address. vmalloc uses up
the kernel virtual address space. By replacing vmalloc with physical
page alloction and mapping that allocation to kernel space only
when it is required prevents the kgsl driver from using unnecessary
vmalloc virtual space.
kmalloc allocates physically contiguous memory and
may fail for larger allocations due to fragmentation.
The large allocations are caused by the fact that the
scatterlist structure is 24 bytes and the array size
is proportional to the number of pages being mapped.
Certain memory allocations are not properly tracked by kmemleak tool,
which makes it to incorrectly detect memory leak. Notify the tool by using
kmemleak_not_leak() to ignore the memory allocation so that incorrect leaks
report are avoided.
