V4L/DVB (11840): change kmalloc to vmalloc for sglist allocation in videobuf_dma_map/unmap
Change kmalloc()/kfree() to vmalloc()/vfree() for sglist allocation
during videobuf_dma_map() and videobuf_dma_unmap()
High resolution sensors might require too many contiguous pages
to be allocated for sglist by kmalloc() during videobuf_dma_map()
(i.e. 256Kib for 8MP sensor).
In such situations, kmalloc() could face some problem to find the
required free memory. vmalloc() is a safer solution instead, as the
allocated memory does not need to be contiguous.
Signed-off-by: David Cohen <david.cohen@nokia.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/videobuf-dma-sg.c b/drivers/media/video/videobuf-dma-sg.c
index da1790e..c9a5d7e 100644
--- a/drivers/media/video/videobuf-dma-sg.c
+++ b/drivers/media/video/videobuf-dma-sg.c
@@ -58,9 +58,10 @@
struct page *pg;
int i;
- sglist = kcalloc(nr_pages, sizeof(struct scatterlist), GFP_KERNEL);
+ sglist = vmalloc(nr_pages * sizeof(*sglist));
if (NULL == sglist)
return NULL;
+ memset(sglist, 0, nr_pages * sizeof(*sglist));
sg_init_table(sglist, nr_pages);
for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
pg = vmalloc_to_page(virt);
@@ -72,7 +73,7 @@
return sglist;
err:
- kfree(sglist);
+ vfree(sglist);
return NULL;
}
@@ -84,7 +85,7 @@
if (NULL == pages[0])
return NULL;
- sglist = kmalloc(nr_pages * sizeof(*sglist), GFP_KERNEL);
+ sglist = vmalloc(nr_pages * sizeof(*sglist));
if (NULL == sglist)
return NULL;
sg_init_table(sglist, nr_pages);
@@ -104,12 +105,12 @@
nopage:
dprintk(2,"sgl: oops - no page\n");
- kfree(sglist);
+ vfree(sglist);
return NULL;
highmem:
dprintk(2,"sgl: oops - highmem page\n");
- kfree(sglist);
+ vfree(sglist);
return NULL;
}
@@ -230,7 +231,7 @@
(dma->vmalloc,dma->nr_pages);
}
if (dma->bus_addr) {
- dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
+ dma->sglist = vmalloc(sizeof(*dma->sglist));
if (NULL != dma->sglist) {
dma->sglen = 1;
sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
@@ -248,7 +249,7 @@
if (0 == dma->sglen) {
printk(KERN_WARNING
"%s: videobuf_map_sg failed\n",__func__);
- kfree(dma->sglist);
+ vfree(dma->sglist);
dma->sglist = NULL;
dma->sglen = 0;
return -EIO;
@@ -274,7 +275,7 @@
dma_unmap_sg(q->dev, dma->sglist, dma->nr_pages, dma->direction);
- kfree(dma->sglist);
+ vfree(dma->sglist);
dma->sglist = NULL;
dma->sglen = 0;
return 0;