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| author | Matthew Wilcox <willy@infradead.org> | 2021-06-01 15:30:30 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2021-06-01 17:38:40 +0200 |
| commit | 0b78f8bcf4951af30b0ae83ea4fad27d641ab617 (patch) | |
| tree | 6545ba613e36b540815717431b9b157b67cbe651 | |
| parent | 8124c8a6b35386f73523d27eacb71b5364a68c4c (diff) | |
| download | lwn-0b78f8bcf4951af30b0ae83ea4fad27d641ab617.tar.gz lwn-0b78f8bcf4951af30b0ae83ea4fad27d641ab617.zip | |
Revert "fb_defio: Remove custom address_space_operations"
Commit ccf953d8f3d6 makes framebuffers which use deferred I/O stop
displaying updates after the first one. This is because the pages
handled by fb_defio no longer have a page_mapping(). That prevents
page_mkclean() from marking the PTEs as clean, and so writes are only
noticed the first time.
Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/YLZEhv0cpZp8uVE3@casper.infradead.org
| -rw-r--r-- | drivers/video/fbdev/core/fb_defio.c | 35 | ||||
| -rw-r--r-- | drivers/video/fbdev/core/fbmem.c | 4 | ||||
| -rw-r--r-- | include/linux/fb.h | 3 |
3 files changed, 42 insertions, 0 deletions
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c index b292887a2481..a591d291b231 100644 --- a/drivers/video/fbdev/core/fb_defio.c +++ b/drivers/video/fbdev/core/fb_defio.c @@ -52,6 +52,13 @@ 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; @@ -144,6 +151,17 @@ 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; @@ -194,12 +212,29 @@ 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 072780b0e570..98f193078c05 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1415,6 +1415,10 @@ __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 a8dccd23c249..ecfbcc0553a5 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -659,6 +659,9 @@ 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); |