diff options
| -rw-r--r-- | Documentation/fb/deferred_io.txt | 6 | ||||
| -rw-r--r-- | drivers/video/fb_defio.c | 17 |
2 files changed, 11 insertions, 12 deletions
diff --git a/Documentation/fb/deferred_io.txt b/Documentation/fb/deferred_io.txt index 63883a8..7483283 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 works: - userspace app like Xfbdev mmaps framebuffer -- deferred IO and driver sets up nopage and page_mkwrite handlers +- deferred IO and driver sets up fault and page_mkwrite handlers - userspace app tries to write to mmaped vaddress -- we get pagefault and reach nopage handler -- nopage handler finds and returns physical page +- we get pagefault and reach fault handler +- fault handler finds and returns physical page - we get page_mkwrite where we add this page to a list - schedule a workqueue task to be run after a delay - 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 a0c5d9d..0f8cfb9 100644 --- a/drivers/video/fb_defio.c +++ b/drivers/video/fb_defio.c @@ -25,8 +25,8 @@ #include <linux/pagemap.h> /* this is to find and return the vmalloc-ed fb pages */ -static struct page* fb_deferred_io_nopage(struct vm_area_struct *vma, - unsigned long vaddr, int *type) +static int fb_deferred_io_fault(struct vm_area_struct *vma, + struct vm_fault *vmf) { unsigned long offset; struct page *page; @@ -34,18 +34,17 @@ static struct page* fb_deferred_io_nopage(struct vm_area_struct *vma, /* info->screen_base is in System RAM */ void *screen_base = (void __force *) info->screen_base; - offset = (vaddr - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT); + offset = vmf->pgoff << PAGE_SHIFT; if (offset >= info->fix.smem_len) - return NOPAGE_SIGBUS; + return VM_FAULT_SIGBUS; page = vmalloc_to_page(screen_base + offset); if (!page) - return NOPAGE_OOM; + return VM_FAULT_SIGBUS; get_page(page); - if (type) - *type = VM_FAULT_MINOR; - return page; + vmf->page = page; + return 0; } int 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, } static struct vm_operations_struct fb_deferred_io_vm_ops = { - .nopage = fb_deferred_io_nopage, + .fault = fb_deferred_io_fault, .page_mkwrite = fb_deferred_io_mkwrite, }; |
