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[media] videobuf-dma-contig: add cache support
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Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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Federico Vaga authored and Mauro Carvalho Chehab committed May 20, 2012
1 parent bca7ad1 commit a8f3c20
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Showing 2 changed files with 159 additions and 50 deletions.
199 changes: 149 additions & 50 deletions drivers/media/video/videobuf-dma-contig.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,7 @@ struct videobuf_dma_contig_memory {
u32 magic;
void *vaddr;
dma_addr_t dma_handle;
bool cached;
unsigned long size;
};

Expand All @@ -37,8 +38,58 @@ struct videobuf_dma_contig_memory {
BUG(); \
}

static void
videobuf_vm_open(struct vm_area_struct *vma)
static int __videobuf_dc_alloc(struct device *dev,
struct videobuf_dma_contig_memory *mem,
unsigned long size, unsigned long flags)
{
mem->size = size;
if (mem->cached) {
mem->vaddr = alloc_pages_exact(mem->size, flags | GFP_DMA);
if (mem->vaddr) {
int err;

mem->dma_handle = dma_map_single(dev, mem->vaddr,
mem->size,
DMA_FROM_DEVICE);
err = dma_mapping_error(dev, mem->dma_handle);
if (err) {
dev_err(dev, "dma_map_single failed\n");

free_pages_exact(mem->vaddr, mem->size);
mem->vaddr = 0;
return err;
}
}
} else
mem->vaddr = dma_alloc_coherent(dev, mem->size,
&mem->dma_handle, flags);

if (!mem->vaddr) {
dev_err(dev, "memory alloc size %ld failed\n", mem->size);
return -ENOMEM;
}

dev_dbg(dev, "dma mapped data is at %p (%ld)\n", mem->vaddr, mem->size);

return 0;
}

static void __videobuf_dc_free(struct device *dev,
struct videobuf_dma_contig_memory *mem)
{
if (mem->cached) {
if (!mem->vaddr)
return;
dma_unmap_single(dev, mem->dma_handle, mem->size,
DMA_FROM_DEVICE);
free_pages_exact(mem->vaddr, mem->size);
} else
dma_free_coherent(dev, mem->size, mem->vaddr, mem->dma_handle);

mem->vaddr = NULL;
}

static void videobuf_vm_open(struct vm_area_struct *vma)
{
struct videobuf_mapping *map = vma->vm_private_data;

Expand Down Expand Up @@ -91,12 +142,11 @@ static void videobuf_vm_close(struct vm_area_struct *vma)
dev_dbg(q->dev, "buf[%d] freeing %p\n",
i, mem->vaddr);

dma_free_coherent(q->dev, mem->size,
mem->vaddr, mem->dma_handle);
__videobuf_dc_free(q->dev, mem);
mem->vaddr = NULL;
}

q->bufs[i]->map = NULL;
q->bufs[i]->map = NULL;
q->bufs[i]->baddr = 0;
}

Expand All @@ -107,8 +157,8 @@ static void videobuf_vm_close(struct vm_area_struct *vma)
}

static const struct vm_operations_struct videobuf_vm_ops = {
.open = videobuf_vm_open,
.close = videobuf_vm_close,
.open = videobuf_vm_open,
.close = videobuf_vm_close,
};

/**
Expand Down Expand Up @@ -178,26 +228,38 @@ static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem,
pages_done++;
}

out_up:
out_up:
up_read(&current->mm->mmap_sem);

return ret;
}

static struct videobuf_buffer *__videobuf_alloc_vb(size_t size)
static struct videobuf_buffer *__videobuf_alloc_vb(size_t size, bool cached)
{
struct videobuf_dma_contig_memory *mem;
struct videobuf_buffer *vb;

vb = kzalloc(size + sizeof(*mem), GFP_KERNEL);
if (vb) {
mem = vb->priv = ((char *)vb) + size;
vb->priv = ((char *)vb) + size;
mem = vb->priv;
mem->magic = MAGIC_DC_MEM;
mem->cached = cached;
}

return vb;
}

static struct videobuf_buffer *__videobuf_alloc_uncached(size_t size)
{
return __videobuf_alloc_vb(size, false);
}

static struct videobuf_buffer *__videobuf_alloc_cached(size_t size)
{
return __videobuf_alloc_vb(size, true);
}

static void *__videobuf_to_vaddr(struct videobuf_buffer *buf)
{
struct videobuf_dma_contig_memory *mem = buf->priv;
Expand Down Expand Up @@ -235,28 +297,32 @@ static int __videobuf_iolock(struct videobuf_queue *q,
return videobuf_dma_contig_user_get(mem, vb);

/* allocate memory for the read() method */
mem->size = PAGE_ALIGN(vb->size);
mem->vaddr = dma_alloc_coherent(q->dev, mem->size,
&mem->dma_handle, GFP_KERNEL);
if (!mem->vaddr) {
dev_err(q->dev, "dma_alloc_coherent %ld failed\n",
mem->size);
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(vb->size),
GFP_KERNEL))
return -ENOMEM;
}

dev_dbg(q->dev, "dma_alloc_coherent data is at %p (%ld)\n",
mem->vaddr, mem->size);
break;
case V4L2_MEMORY_OVERLAY:
default:
dev_dbg(q->dev, "%s memory method OVERLAY/unknown\n",
__func__);
dev_dbg(q->dev, "%s memory method OVERLAY/unknown\n", __func__);
return -EINVAL;
}

return 0;
}

static int __videobuf_sync(struct videobuf_queue *q,
struct videobuf_buffer *buf)
{
struct videobuf_dma_contig_memory *mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);

dma_sync_single_for_cpu(q->dev, mem->dma_handle, mem->size,
DMA_FROM_DEVICE);

return 0;
}

static int __videobuf_mmap_mapper(struct videobuf_queue *q,
struct videobuf_buffer *buf,
struct vm_area_struct *vma)
Expand All @@ -265,6 +331,8 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
struct videobuf_mapping *map;
int retval;
unsigned long size;
unsigned long pos, start = vma->vm_start;
struct page *page;

dev_dbg(q->dev, "%s\n", __func__);

Expand All @@ -282,41 +350,50 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);

mem->size = PAGE_ALIGN(buf->bsize);
mem->vaddr = dma_alloc_coherent(q->dev, mem->size,
&mem->dma_handle, GFP_KERNEL);
if (!mem->vaddr) {
dev_err(q->dev, "dma_alloc_coherent size %ld failed\n",
mem->size);
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(buf->bsize),
GFP_KERNEL | __GFP_COMP))
goto error;
}
dev_dbg(q->dev, "dma_alloc_coherent data is at addr %p (size %ld)\n",
mem->vaddr, mem->size);

/* Try to remap memory */

size = vma->vm_end - vma->vm_start;
size = (size < mem->size) ? size : mem->size;

vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
retval = remap_pfn_range(vma, vma->vm_start,
mem->dma_handle >> PAGE_SHIFT,
size, vma->vm_page_prot);
if (retval) {
dev_err(q->dev, "mmap: remap failed with error %d. ", retval);
dma_free_coherent(q->dev, mem->size,
mem->vaddr, mem->dma_handle);
goto error;
if (!mem->cached)
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

pos = (unsigned long)mem->vaddr;

while (size > 0) {
page = virt_to_page((void *)pos);
if (NULL == page) {
dev_err(q->dev, "mmap: virt_to_page failed\n");
__videobuf_dc_free(q->dev, mem);
goto error;
}
retval = vm_insert_page(vma, start, page);
if (retval) {
dev_err(q->dev, "mmap: insert failed with error %d\n",
retval);
__videobuf_dc_free(q->dev, mem);
goto error;
}
start += PAGE_SIZE;
pos += PAGE_SIZE;

if (size > PAGE_SIZE)
size -= PAGE_SIZE;
else
size = 0;
}

vma->vm_ops = &videobuf_vm_ops;
vma->vm_flags |= VM_DONTEXPAND;
vma->vm_ops = &videobuf_vm_ops;
vma->vm_flags |= VM_DONTEXPAND;
vma->vm_private_data = map;

dev_dbg(q->dev, "mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
map, q, vma->vm_start, vma->vm_end,
(long int)buf->bsize,
vma->vm_pgoff, buf->i);
(long int)buf->bsize, vma->vm_pgoff, buf->i);

videobuf_vm_open(vma);

Expand All @@ -328,12 +405,20 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
}

static struct videobuf_qtype_ops qops = {
.magic = MAGIC_QTYPE_OPS,
.magic = MAGIC_QTYPE_OPS,
.alloc_vb = __videobuf_alloc_uncached,
.iolock = __videobuf_iolock,
.mmap_mapper = __videobuf_mmap_mapper,
.vaddr = __videobuf_to_vaddr,
};

.alloc_vb = __videobuf_alloc_vb,
.iolock = __videobuf_iolock,
.mmap_mapper = __videobuf_mmap_mapper,
.vaddr = __videobuf_to_vaddr,
static struct videobuf_qtype_ops qops_cached = {
.magic = MAGIC_QTYPE_OPS,
.alloc_vb = __videobuf_alloc_cached,
.iolock = __videobuf_iolock,
.sync = __videobuf_sync,
.mmap_mapper = __videobuf_mmap_mapper,
.vaddr = __videobuf_to_vaddr,
};

void videobuf_queue_dma_contig_init(struct videobuf_queue *q,
Expand All @@ -351,6 +436,20 @@ void videobuf_queue_dma_contig_init(struct videobuf_queue *q,
}
EXPORT_SYMBOL_GPL(videobuf_queue_dma_contig_init);

void videobuf_queue_dma_contig_init_cached(struct videobuf_queue *q,
const struct videobuf_queue_ops *ops,
struct device *dev,
spinlock_t *irqlock,
enum v4l2_buf_type type,
enum v4l2_field field,
unsigned int msize,
void *priv, struct mutex *ext_lock)
{
videobuf_queue_core_init(q, ops, dev, irqlock, type, field, msize,
priv, &qops_cached, ext_lock);
}
EXPORT_SYMBOL_GPL(videobuf_queue_dma_contig_init_cached);

dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf)
{
struct videobuf_dma_contig_memory *mem = buf->priv;
Expand Down Expand Up @@ -389,7 +488,7 @@ void videobuf_dma_contig_free(struct videobuf_queue *q,

/* read() method */
if (mem->vaddr) {
dma_free_coherent(q->dev, mem->size, mem->vaddr, mem->dma_handle);
__videobuf_dc_free(q->dev, mem);
mem->vaddr = NULL;
}
}
Expand Down
10 changes: 10 additions & 0 deletions include/media/videobuf-dma-contig.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,16 @@ void videobuf_queue_dma_contig_init(struct videobuf_queue *q,
void *priv,
struct mutex *ext_lock);

void videobuf_queue_dma_contig_init_cached(struct videobuf_queue *q,
const struct videobuf_queue_ops *ops,
struct device *dev,
spinlock_t *irqlock,
enum v4l2_buf_type type,
enum v4l2_field field,
unsigned int msize,
void *priv,
struct mutex *ext_lock);

dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf);
void videobuf_dma_contig_free(struct videobuf_queue *q,
struct videobuf_buffer *buf);
Expand Down

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