[PATCH v2] fb_defio: Remove custom address_space_operations

Matthew Wilcox (Oracle)
2021-03-10T18:56:14Z

There's no need to give the page an address_space. Leaving the
page->mapping as NULL will cause the VM to handle set_page_dirty()
the same way that it's handled now, and that was the only reason to
set the address_space in the first place.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
---
v2: Delete local variable definitions
drivers/video/fbdev/core/fb_defio.c | 35 -----------------------------
drivers/video/fbdev/core/fbmem.c | 4 ----
include/linux/fb.h | 3 ---
3 files changed, 42 deletions(-)

diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
index a591d291b231..b292887a2481 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -52,13 +52,6 @@ static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
return VM_FAULT_SIGBUS;

get_page(page);
-
- if (vmf->vma->vm_file)
- page->mapping = vmf->vma->vm_file->f_mapping;
- else
- printk(KERN_ERR "no mapping available\n");
-
- BUG_ON(!page->mapping);
page->index = vmf->pgoff;

vmf->page = page;
@@ -151,17 +144,6 @@ static const struct vm_operations_struct fb_deferred_io_vm_ops = {
.page_mkwrite = fb_deferred_io_mkwrite,
};

-static int fb_deferred_io_set_page_dirty(struct page *page)
-{
- if (!PageDirty(page))
- SetPageDirty(page);
- return 0;
-}
-
-static const struct address_space_operations fb_deferred_io_aops = {
- .set_page_dirty = fb_deferred_io_set_page_dirty,
-};
-
int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
vma->vm_ops = &fb_deferred_io_vm_ops;
@@ -212,29 +194,12 @@ void fb_deferred_io_init(struct fb_info *info)
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);

-void fb_deferred_io_open(struct fb_info *info,
- struct inode *inode,
- struct file *file)
-{
- file->f_mapping->a_ops = &fb_deferred_io_aops;
-}
-EXPORT_SYMBOL_GPL(fb_deferred_io_open);
-
void fb_deferred_io_cleanup(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
- struct page *page;
- int i;

BUG_ON(!fbdefio);
cancel_delayed_work_sync(&info->deferred_work);
-
- /* clear out the mapping that we setup */
- for (i = 0 ; i < info->fix.smem_len; i += PAGE_SIZE) {
- page = fb_deferred_io_page(info, i);
- page->mapping = NULL;
- }
-
mutex_destroy(&fbdefio->lock);
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 06f5805de2de..372b52a2befa 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1415,10 +1415,6 @@ __releases(&info->lock)
if (res)
module_put(info->fbops->owner);
}
-#ifdef CONFIG_FB_DEFERRED_IO
- if (info->fbdefio)
- fb_deferred_io_open(info, inode, file);
-#endif
out:
unlock_fb_info(info);
if (res)
diff --git a/include/linux/fb.h b/include/linux/fb.h
index ecfbcc0553a5..a8dccd23c249 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -659,9 +659,6 @@ static inline void __fb_pad_aligned_buffer(u8 *dst, u32 d_pitch,
/* drivers/video/fb_defio.c */
int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma);
extern void fb_deferred_io_init(struct fb_info *info);
-extern void fb_deferred_io_open(struct fb_info *info,
- struct inode *inode,
- struct file *file);
extern void fb_deferred_io_cleanup(struct fb_info *info);
extern int fb_deferred_io_fsync(struct file *file, loff_t start,
loff_t end, int datasync);
--
2.30.0