In preparation for the switch to the DMA API merge the two functions
that handle buffer preparation for the USERPTR cases (both page-backed
and non page-backed memory).
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/platform/omap3isp/ispqueue.c | 169 ++++++++++++-----------------
drivers/media/platform/omap3isp/ispqueue.h | 4 -
2 files changed, 69 insertions(+), 104 deletions(-)
diff --git a/drivers/media/platform/omap3isp/ispqueue.c b/drivers/media/platform/omap3isp/ispqueue.c
index 51ec40d..a7be7d7 100644
--- a/drivers/media/platform/omap3isp/ispqueue.c
+++ b/drivers/media/platform/omap3isp/ispqueue.c
@@ -178,12 +178,12 @@ out:
}
/*
- * isp_video_buffer_sglist_kernel - Build a scatter list for a vmalloc'ed buffer
+ * isp_video_buffer_prepare_kernel - Build scatter list for a vmalloc'ed buffer
*
* Iterate over the vmalloc'ed area and create a scatter list entry for every
* page.
*/
-static int isp_video_buffer_sglist_kernel(struct isp_video_buffer *buf)
+static int isp_video_buffer_prepare_kernel(struct isp_video_buffer *buf)
{
struct scatterlist *sg;
unsigned int npages;
@@ -214,67 +214,6 @@ static int isp_video_buffer_sglist_kernel(struct isp_video_buffer *buf)
}
/*
- * isp_video_buffer_sglist_user - Build a scatter list for a userspace buffer
- *
- * Walk the buffer pages list and create a 1:1 mapping to a scatter list.
- */
-static int isp_video_buffer_sglist_user(struct isp_video_buffer *buf)
-{
- unsigned int offset = buf->offset;
- struct scatterlist *sg;
- unsigned int i;
- int ret;
-
- ret = sg_alloc_table(&buf->sgt, buf->npages, GFP_KERNEL);
- if (ret < 0)
- return ret;
-
- for (sg = buf->sgt.sgl, i = 0; i < buf->npages; ++i) {
- if (PageHighMem(buf->pages[i])) {
- sg_free_table(&buf->sgt);
- return -EINVAL;
- }
-
- sg_set_page(sg, buf->pages[i], PAGE_SIZE - offset, offset);
- sg = sg_next(sg);
- offset = 0;
- }
-
- return 0;
-}
-
-/*
- * isp_video_buffer_sglist_pfnmap - Build a scatter list for a VM_PFNMAP buffer
- *
- * Create a scatter list of physically contiguous pages starting at the buffer
- * memory physical address.
- */
-static int isp_video_buffer_sglist_pfnmap(struct isp_video_buffer *buf)
-{
- struct scatterlist *sg;
- unsigned int offset = buf->offset;
- unsigned long pfn = buf->paddr >> PAGE_SHIFT;
- unsigned int i;
- int ret;
-
- ret = sg_alloc_table(&buf->sgt, buf->npages, GFP_KERNEL);
- if (ret < 0)
- return ret;
-
- for (sg = buf->sgt.sgl, i = 0; i < buf->npages; ++i, ++pfn) {
- sg_set_page(sg, pfn_to_page(pfn), PAGE_SIZE - offset, offset);
- /* PFNMAP buffers will not get DMA-mapped, set the DMA address
- * manually.
- */
- sg_dma_address(sg) = (pfn << PAGE_SHIFT) + offset;
- sg = sg_next(sg);
- offset = 0;
- }
-
- return 0;
-}
-
-/*
* isp_video_buffer_cleanup - Release pages for a userspace VMA.
*
* Release pages locked by a call isp_video_buffer_prepare_user and free the
@@ -316,11 +255,11 @@ static void isp_video_buffer_cleanup(struct isp_video_buffer *buf)
}
/*
- * isp_video_buffer_prepare_user - Pin userspace VMA pages to memory.
+ * isp_video_buffer_prepare_user - Prepare a userspace buffer.
*
- * This function creates a list of pages for a userspace VMA. The number of
- * pages is first computed based on the buffer size, and pages are then
- * retrieved by a call to get_user_pages.
+ * This function creates a scatter list with a 1:1 mapping for a userspace VMA.
+ * The number of pages is first computed based on the buffer size, and pages are
+ * then retrieved by a call to get_user_pages.
*
* Pages are pinned to memory by get_user_pages, making them available for DMA
* transfers. However, due to memory management optimization, it seems the
@@ -340,16 +279,19 @@ static void isp_video_buffer_cleanup(struct isp_video_buffer *buf)
*/
static int isp_video_buffer_prepare_user(struct isp_video_buffer *buf)
{
+ struct scatterlist *sg;
+ unsigned int offset;
unsigned long data;
unsigned int first;
unsigned int last;
+ unsigned int i;
int ret;
data = buf->vbuf.m.userptr;
first = (data & PAGE_MASK) >> PAGE_SHIFT;
last = ((data + buf->vbuf.length - 1) & PAGE_MASK) >> PAGE_SHIFT;
+ offset = data & ~PAGE_MASK;
- buf->offset = data & ~PAGE_MASK;
buf->npages = last - first + 1;
buf->pages = vmalloc(buf->npages * sizeof(buf->pages[0]));
if (buf->pages == NULL)
@@ -364,68 +306,104 @@ static int isp_video_buffer_prepare_user(struct isp_video_buffer *buf)
if (ret != buf->npages) {
buf->npages = ret < 0 ? 0 : ret;
- isp_video_buffer_cleanup(buf);
return -EFAULT;
}
ret = isp_video_buffer_lock_vma(buf, 1);
if (ret < 0)
- isp_video_buffer_cleanup(buf);
+ return ret;
- return ret;
+ ret = sg_alloc_table(&buf->sgt, buf->npages, GFP_KERNEL);
+ if (ret < 0)
+ return ret;
+
+ for (sg = buf->sgt.sgl, i = 0; i < buf->npages; ++i) {
+ if (PageHighMem(buf->pages[i])) {
+ sg_free_table(&buf->sgt);
+ return -EINVAL;
+ }
+
+ sg_set_page(sg, buf->pages[i], PAGE_SIZE - offset, offset);
+ sg = sg_next(sg);
+ offset = 0;
+ }
+
+ return 0;
}
/*
- * isp_video_buffer_prepare_pfnmap - Validate a VM_PFNMAP userspace buffer
+ * isp_video_buffer_prepare_pfnmap - Prepare a VM_PFNMAP userspace buffer
*
* Userspace VM_PFNMAP buffers are supported only if they are contiguous in
- * memory and if they span a single VMA.
+ * memory and if they span a single VMA. Start by validating the user pointer to
+ * make sure it fulfils that condition, and then build a scatter list of
+ * physically contiguous pages starting at the buffer memory physical address.
*
- * Return 0 if the buffer is valid, or -EFAULT otherwise.
+ * Return 0 on success, -EFAULT if the buffer isn't valid or -ENOMEM if memory
+ * can't be allocated.
*/
static int isp_video_buffer_prepare_pfnmap(struct isp_video_buffer *buf)
{
struct vm_area_struct *vma;
+ struct scatterlist *sg;
unsigned long prev_pfn;
unsigned long this_pfn;
unsigned long start;
+ unsigned int offset;
unsigned long end;
- dma_addr_t pa = 0;
- int ret = -EFAULT;
+ unsigned long pfn;
+ unsigned int i;
+ int ret = 0;
start = buf->vbuf.m.userptr;
end = buf->vbuf.m.userptr + buf->vbuf.length - 1;
+ offset = start & ~PAGE_MASK;
- buf->offset = start & ~PAGE_MASK;
buf->npages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1;
buf->pages = NULL;
down_read(¤t->mm->mmap_sem);
vma = find_vma(current->mm, start);
- if (vma == NULL || vma->vm_end < end)
- goto done;
+ if (vma == NULL || vma->vm_end < end) {
+ ret = -EFAULT;
+ goto unlock;
+ }
for (prev_pfn = 0; start <= end; start += PAGE_SIZE) {
ret = follow_pfn(vma, start, &this_pfn);
- if (ret)
- goto done;
+ if (ret < 0)
+ goto unlock;
if (prev_pfn == 0)
- pa = this_pfn << PAGE_SHIFT;
+ pfn = this_pfn;
else if (this_pfn != prev_pfn + 1) {
ret = -EFAULT;
- goto done;
+ goto unlock;
}
prev_pfn = this_pfn;
}
- buf->paddr = pa + buf->offset;
- ret = 0;
-
-done:
+unlock:
up_read(¤t->mm->mmap_sem);
- return ret;
+ if (ret < 0)
+ return ret;
+
+ ret = sg_alloc_table(&buf->sgt, buf->npages, GFP_KERNEL);
+ if (ret < 0)
+ return ret;
+
+ for (sg = buf->sgt.sgl, i = 0; i < buf->npages; ++i, ++pfn) {
+ sg_set_page(sg, pfn_to_page(pfn), PAGE_SIZE - offset, offset);
+ /* PFNMAP buffers will not get DMA-mapped, set the DMA address
+ * manually.
+ */
+ sg_dma_address(sg) = (pfn << PAGE_SHIFT) + offset;
+ sg = sg_next(sg);
+ offset = 0;
+ }
+
+ return 0;
}
/*
@@ -511,7 +489,7 @@ static int isp_video_buffer_prepare(struct isp_video_buffer *buf)
switch (buf->vbuf.memory) {
case V4L2_MEMORY_MMAP:
- ret = isp_video_buffer_sglist_kernel(buf);
+ ret = isp_video_buffer_prepare_kernel(buf);
break;
case V4L2_MEMORY_USERPTR:
@@ -519,19 +497,10 @@ static int isp_video_buffer_prepare(struct isp_video_buffer *buf)
if (ret < 0)
return ret;
- if (buf->vm_flags & VM_PFNMAP) {
+ if (buf->vm_flags & VM_PFNMAP)
ret = isp_video_buffer_prepare_pfnmap(buf);
- if (ret < 0)
- return ret;
-
- ret = isp_video_buffer_sglist_pfnmap(buf);
- } else {
+ else
ret = isp_video_buffer_prepare_user(buf);
- if (ret < 0)
- return ret;
-
- ret = isp_video_buffer_sglist_user(buf);
- }
break;
default:
diff --git a/drivers/media/platform/omap3isp/ispqueue.h b/drivers/media/platform/omap3isp/ispqueue.h
index 99c11e8..f78325d 100644
--- a/drivers/media/platform/omap3isp/ispqueue.h
+++ b/drivers/media/platform/omap3isp/ispqueue.h
@@ -69,10 +69,8 @@ enum isp_video_buffer_state {
* @skip_cache: Whether to skip cache management operations for this buffer
* @vaddr: Memory virtual address (for kernel buffers)
* @vm_flags: Buffer VMA flags (for userspace buffers)
- * @offset: Offset inside the first page (for userspace buffers)
* @npages: Number of pages (for userspace buffers)
* @pages: Pages table (for userspace non-VM_PFNMAP buffers)
- * @paddr: Memory physical address (for userspace VM_PFNMAP buffers)
* @sgt: Scatter gather table (for non-VM_PFNMAP buffers)
* @vbuf: V4L2 buffer
* @irqlist: List head for insertion into IRQ queue
@@ -91,10 +89,8 @@ struct isp_video_buffer {
/* For userspace buffers. */
vm_flags_t vm_flags;
- unsigned long offset;
unsigned int npages;
struct page **pages;
- dma_addr_t paddr;
/* For all buffers except VM_PFNMAP. */
struct sg_table sgt;
--
1.8.3.2
--
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