aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/fb/deferred_io.txt6
-rw-r--r--drivers/video/fb_defio.c17
2 files changed, 11 insertions, 12 deletions
diff --git a/Documentation/fb/deferred_io.txt b/Documentation/fb/deferred_io.txt
index 63883a892120..748328370250 100644
--- a/Documentation/fb/deferred_io.txt
+++ b/Documentation/fb/deferred_io.txt
@@ -7,10 +7,10 @@ IO. The following example may be a useful explanation of how one such setup
7works: 7works:
8 8
9- userspace app like Xfbdev mmaps framebuffer 9- userspace app like Xfbdev mmaps framebuffer
10- deferred IO and driver sets up nopage and page_mkwrite handlers 10- deferred IO and driver sets up fault and page_mkwrite handlers
11- userspace app tries to write to mmaped vaddress 11- userspace app tries to write to mmaped vaddress
12- we get pagefault and reach nopage handler 12- we get pagefault and reach fault handler
13- nopage handler finds and returns physical page 13- fault handler finds and returns physical page
14- we get page_mkwrite where we add this page to a list 14- we get page_mkwrite where we add this page to a list
15- schedule a workqueue task to be run after a delay 15- schedule a workqueue task to be run after a delay
16- app continues writing to that page with no additional cost. this is 16- app continues writing to that page with no additional cost. this is
diff --git a/drivers/video/fb_defio.c b/drivers/video/fb_defio.c
index a0c5d9d90d74..0f8cfb988c90 100644
--- a/drivers/video/fb_defio.c
+++ b/drivers/video/fb_defio.c
@@ -25,8 +25,8 @@
25#include <linux/pagemap.h> 25#include <linux/pagemap.h>
26 26
27/* this is to find and return the vmalloc-ed fb pages */ 27/* this is to find and return the vmalloc-ed fb pages */
28static struct page* fb_deferred_io_nopage(struct vm_area_struct *vma, 28static int fb_deferred_io_fault(struct vm_area_struct *vma,
29 unsigned long vaddr, int *type) 29 struct vm_fault *vmf)
30{ 30{
31 unsigned long offset; 31 unsigned long offset;
32 struct page *page; 32 struct page *page;
@@ -34,18 +34,17 @@ static struct page* fb_deferred_io_nopage(struct vm_area_struct *vma,
34 /* info->screen_base is in System RAM */ 34 /* info->screen_base is in System RAM */
35 void *screen_base = (void __force *) info->screen_base; 35 void *screen_base = (void __force *) info->screen_base;
36 36
37 offset = (vaddr - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT); 37 offset = vmf->pgoff << PAGE_SHIFT;
38 if (offset >= info->fix.smem_len) 38 if (offset >= info->fix.smem_len)
39 return NOPAGE_SIGBUS; 39 return VM_FAULT_SIGBUS;
40 40
41 page = vmalloc_to_page(screen_base + offset); 41 page = vmalloc_to_page(screen_base + offset);
42 if (!page) 42 if (!page)
43 return NOPAGE_OOM; 43 return VM_FAULT_SIGBUS;
44 44
45 get_page(page); 45 get_page(page);
46 if (type) 46 vmf->page = page;
47 *type = VM_FAULT_MINOR; 47 return 0;
48 return page;
49} 48}
50 49
51int fb_deferred_io_fsync(struct file *file, struct dentry *dentry, int datasync) 50int fb_deferred_io_fsync(struct file *file, struct dentry *dentry, int datasync)
@@ -84,7 +83,7 @@ static int fb_deferred_io_mkwrite(struct vm_area_struct *vma,
84} 83}
85 84
86static struct vm_operations_struct fb_deferred_io_vm_ops = { 85static struct vm_operations_struct fb_deferred_io_vm_ops = {
87 .nopage = fb_deferred_io_nopage, 86 .fault = fb_deferred_io_fault,
88 .page_mkwrite = fb_deferred_io_mkwrite, 87 .page_mkwrite = fb_deferred_io_mkwrite,
89}; 88};
90 89