[PATCH] video: arch specific page protection support for deferred io
From: Magnus Damm <magnus.damm@gmail.com>
Date: 2009-06-24 10:56:03
Also in:
linux-mm
From: Magnus Damm <redacted> This patch adds arch specific page protection support to deferred io. Instead of overwriting the info->fbops->mmap pointer with the deferred io specific mmap callback, modify fb_mmap() to include a #ifdef wrapped call to fb_deferred_io_mmap(). The function fb_deferred_io_mmap() is extended to call fb_pgprotect() in the case of non-vmalloc() frame buffers. With this patch uncached deferred io can be used together with the sh_mobile_lcdcfb driver. Without this patch arch specific page protection code in fb_pgprotect() never gets invoked with deferred io. Signed-off-by: Magnus Damm <redacted> --- For proper runtime operation with uncached vmas make sure "[PATCH][RFC] mm: uncached vma support with writenotify" is applied. There are no merge order dependencies. drivers/video/fb_defio.c | 10 +++++++--- drivers/video/fbmem.c | 6 ++++++ include/linux/fb.h | 2 ++ 3 files changed, 15 insertions(+), 3 deletions(-)
--- 0001/drivers/video/fb_defio.c
+++ work/drivers/video/fb_defio.c 2009-06-24 19:07:11.000000000 +0900@@ -19,6 +19,7 @@ #include <linux/interrupt.h> #include <linux/fb.h> #include <linux/list.h> +#include <asm/fb.h> /* to support deferred IO */ #include <linux/rmap.h>
@@ -141,11 +142,16 @@ static const struct address_space_operat .set_page_dirty = fb_deferred_io_set_page_dirty, }; -static int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma) +int fb_deferred_io_mmap(struct file *file, struct fb_info *info, + struct vm_area_struct *vma, unsigned long off) { vma->vm_ops = &fb_deferred_io_vm_ops; vma->vm_flags |= ( VM_IO | VM_RESERVED | VM_DONTEXPAND ); vma->vm_private_data = info; + + if (!is_vmalloc_addr(info->screen_base)) + fb_pgprotect(file, vma, off); + return 0; }
@@ -182,7 +188,6 @@ void fb_deferred_io_init(struct fb_info BUG_ON(!fbdefio); mutex_init(&fbdefio->lock); - info->fbops->fb_mmap = fb_deferred_io_mmap; INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work); INIT_LIST_HEAD(&fbdefio->pagelist); if (fbdefio->delay == 0) /* set a default of 1 s */
@@ -214,7 +219,6 @@ void fb_deferred_io_cleanup(struct fb_in page->mapping = NULL; } - info->fbops->fb_mmap = NULL; mutex_destroy(&fbdefio->lock); } EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup); --- 0001/drivers/video/fbmem.c +++ work/drivers/video/fbmem.c 2009-06-24 19:12:29.000000000 +0900
@@ -1325,6 +1325,12 @@ __releases(&info->lock) off = vma->vm_pgoff << PAGE_SHIFT; if (!fb) return -ENODEV; + +#ifdef CONFIG_FB_DEFERRED_IO + if (info->fbdefio) + return fb_deferred_io_mmap(file, info, vma, off); +#endif + if (fb->fb_mmap) { int res; mutex_lock(&info->lock); --- 0001/include/linux/fb.h +++ work/include/linux/fb.h 2009-06-24 19:04:49.000000000 +0900
@@ -1005,6 +1005,8 @@ extern void fb_deferred_io_open(struct f extern void fb_deferred_io_cleanup(struct fb_info *info); extern int fb_deferred_io_fsync(struct file *file, struct dentry *dentry, int datasync); +extern int fb_deferred_io_mmap(struct file *file, struct fb_info *info, + struct vm_area_struct *vma, unsigned long off); static inline bool fb_be_math(struct fb_info *info) { --
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>