diff options
| author | Jani Nikula | 2019-11-29 12:29:31 +0200 |
|---|---|---|
| committer | Jani Nikula | 2019-12-03 11:10:19 +0200 |
| commit | 12281c8dda5a3b47008bd6a6db6645995234b4e1 (patch) | |
| tree | eb66e99d2a1b53c2ff31b364e9b50643c867c115 /drivers/video | |
| parent | dc190678534ee0f9042a65db1613ab1e59582bff (diff) | |
video: fb_defio: preserve user fb_ops
Modifying fb_ops directly to override fb_mmap with fb_deferred_io_mmap
and then resetting it to NULL afterwards causes problems all over the
place. First, it prevents making the fbops member of struct fb_info a
const pointer, which means we can't make struct fb_ops const
anywhere. Second, a few places have to go out of their way to restore
the original fb_mmap pointer that gets reset to NULL.
Since the only user of the fbops->fb_mmap hook is fb_mmap() in fbmem.c,
call fb_deferred_io_mmap() directly when deferred IO is enabled, and
avoid modifying fb_ops altogether.
Simply use info->fbdefio to determine whether deferred IO should be used
or not. This should be accurate enough for all use cases, although
perhaps not pedantically correct.
v2: Simplify considerably by calling fb_deferred_io_mmap() directly
(Daniel, Ville)
Cc: Jaya Kumar <jayalk@intworks.biz>
Cc: linux-fbdev@vger.kernel.org
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/022c82429da15d6450ff9ac1a897322ec3124db4.1575022735.git.jani.nikula@intel.com
Diffstat (limited to 'drivers/video')
| -rw-r--r-- | drivers/video/fbdev/core/fb_defio.c | 3 | ||||
| -rw-r--r-- | drivers/video/fbdev/core/fbmem.c | 15 |
2 files changed, 11 insertions, 7 deletions
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c index 82c20c6047b0..a591d291b231 100644 --- a/drivers/video/fbdev/core/fb_defio.c +++ b/drivers/video/fbdev/core/fb_defio.c @@ -171,7 +171,6 @@ int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma) vma->vm_private_data = info; return 0; } -EXPORT_SYMBOL(fb_deferred_io_mmap); /* workqueue callback */ static void fb_deferred_io_work(struct work_struct *work) @@ -206,7 +205,6 @@ void fb_deferred_io_init(struct fb_info *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 */ @@ -237,7 +235,6 @@ void fb_deferred_io_cleanup(struct fb_info *info) page->mapping = NULL; } - info->fbops->fb_mmap = 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 86b06a599f96..990550930a8e 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1332,16 +1332,23 @@ static int fb_mmap(struct file *file, struct vm_area_struct * vma) { struct fb_info *info = file_fb_info(file); - struct fb_ops *fb; + int (*fb_mmap_fn)(struct fb_info *info, struct vm_area_struct *vma); unsigned long mmio_pgoff; unsigned long start; u32 len; if (!info) return -ENODEV; - fb = info->fbops; mutex_lock(&info->mm_lock); - if (fb->fb_mmap) { + + fb_mmap_fn = info->fbops->fb_mmap; + +#if IS_ENABLED(CONFIG_FB_DEFERRED_IO) + if (info->fbdefio) + fb_mmap_fn = fb_deferred_io_mmap; +#endif + + if (fb_mmap_fn) { int res; /* @@ -1349,7 +1356,7 @@ fb_mmap(struct file *file, struct vm_area_struct * vma) * SME protection is removed ahead of the call */ vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); - res = fb->fb_mmap(info, vma); + res = fb_mmap_fn(info, vma); mutex_unlock(&info->mm_lock); return res; } |