From 5126f2590bee412e3053de851cb07f531e4be36a Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Thu, 10 May 2012 04:57:22 -0300 Subject: [PATCH] [media] v4l2-dev: add flag to have the core lock all file operations This used to be the default if the lock pointer was set, but now that lock is by default only used for ioctl serialization. Those drivers that already used core locking have this flag set explicitly, except for some drivers where it was obvious that there was no need to serialize any file operations other than ioctl. The drivers that didn't need this flag were: drivers/media/radio/dsbr100.c drivers/media/radio/radio-isa.c drivers/media/radio/radio-keene.c drivers/media/radio/radio-miropcm20.c drivers/media/radio/radio-mr800.c drivers/media/radio/radio-tea5764.c drivers/media/radio/radio-timb.c drivers/media/video/vivi.c sound/i2c/other/tea575x-tuner.c The other drivers that use core locking and where it was not immediately obvious that this flag wasn't needed were changed so that the flag is set together with a comment that that driver needs work to avoid having to set that flag. This will often involve taking the core lock in the fops themselves. Eventually this flag should go and it should not be used in new drivers. There are a few reasons why we want to avoid core locking of non-ioctl fops: in the case of mmap this can lead to a deadlock in rare situations since when mmap is called the mmap_sem is held and it is possible for other parts of the code to take that lock as well (copy_from_user()/copy_to_user() perform a down_read(&mm->mmap_sem) when a page fault occurs). It is very unlikely that that happens since the core lock serializes all fops, but the kernel warns about it if lock validation is turned on. For poll it is also undesirable to take the core lock as that can introduce increased latency. The same is true for read/write. While it was possible to make flags or something to turn on/off taking the core lock for each file operation, in practice it is much simpler to just not take it at all except for ioctl and leave it to the driver to take the lock. There are only a handful fops compared to the zillion ioctls we have. I also wanted to make it obvious which drivers still take the lock for all fops, so that's why I chose to have drivers set it explicitly. Signed-off-by: Hans Verkuil Acked-by: Hans de Goede Signed-off-by: Mauro Carvalho Chehab --- drivers/media/common/saa7146_fops.c | 4 +++ drivers/media/radio/wl128x/fmdrv_v4l2.c | 4 +++ drivers/media/video/blackfin/bfin_capture.c | 4 +++ drivers/media/video/cpia2/cpia2_v4l.c | 4 +++ drivers/media/video/cx231xx/cx231xx-video.c | 4 +++ drivers/media/video/davinci/vpbe_display.c | 4 +++ drivers/media/video/davinci/vpif_capture.c | 4 +++ drivers/media/video/davinci/vpif_display.c | 4 +++ drivers/media/video/em28xx/em28xx-video.c | 4 +++ drivers/media/video/fsl-viu.c | 4 +++ drivers/media/video/ivtv/ivtv-streams.c | 4 +++ drivers/media/video/mem2mem_testdev.c | 4 +++ drivers/media/video/mx2_emmaprp.c | 4 +++ drivers/media/video/s2255drv.c | 4 +++ drivers/media/video/s5p-fimc/fimc-capture.c | 4 +++ drivers/media/video/s5p-fimc/fimc-core.c | 4 +++ drivers/media/video/s5p-g2d/g2d.c | 4 +++ drivers/media/video/s5p-jpeg/jpeg-core.c | 8 +++++ drivers/media/video/s5p-mfc/s5p_mfc.c | 6 ++++ drivers/media/video/s5p-tv/mixer_video.c | 4 +++ drivers/media/video/sh_vou.c | 4 +++ drivers/media/video/soc_camera.c | 4 +++ drivers/media/video/tm6000/tm6000-video.c | 4 +++ .../media/video/usbvision/usbvision-video.c | 4 +++ drivers/media/video/v4l2-dev.c | 32 ++++++++++++------- drivers/staging/media/dt3155v4l/dt3155v4l.c | 4 +++ include/media/v4l2-dev.h | 3 ++ 27 files changed, 129 insertions(+), 12 deletions(-) diff --git a/drivers/media/common/saa7146_fops.c b/drivers/media/common/saa7146_fops.c index 71f8e018e5648..8d7df1a0bcd06 100644 --- a/drivers/media/common/saa7146_fops.c +++ b/drivers/media/common/saa7146_fops.c @@ -511,6 +511,10 @@ int saa7146_register_device(struct video_device **vid, struct saa7146_dev* dev, vfd->fops = &video_fops; vfd->ioctl_ops = &dev->ext_vv_data->ops; vfd->release = video_device_release; + /* Locking in file operations other than ioctl should be done by + the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); vfd->lock = &dev->v4l2_lock; vfd->tvnorms = 0; for (i = 0; i < dev->ext_vv_data->num_stds; i++) diff --git a/drivers/media/radio/wl128x/fmdrv_v4l2.c b/drivers/media/radio/wl128x/fmdrv_v4l2.c index 077d369a01731..080b96a61f1a4 100644 --- a/drivers/media/radio/wl128x/fmdrv_v4l2.c +++ b/drivers/media/radio/wl128x/fmdrv_v4l2.c @@ -518,6 +518,10 @@ int fm_v4l2_init_video_device(struct fmdev *fmdev, int radio_nr) video_set_drvdata(gradio_dev, fmdev); gradio_dev->lock = &fmdev->mutex; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &gradio_dev->flags); /* Register with V4L2 subsystem as RADIO device */ if (video_register_device(gradio_dev, VFL_TYPE_RADIO, radio_nr)) { diff --git a/drivers/media/video/blackfin/bfin_capture.c b/drivers/media/video/blackfin/bfin_capture.c index 514fcf742f5a8..0aba45e34f70e 100644 --- a/drivers/media/video/blackfin/bfin_capture.c +++ b/drivers/media/video/blackfin/bfin_capture.c @@ -942,6 +942,10 @@ static int __devinit bcap_probe(struct platform_device *pdev) INIT_LIST_HEAD(&bcap_dev->dma_queue); vfd->lock = &bcap_dev->mutex; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); /* register video device */ ret = video_register_device(bcap_dev->video_dev, VFL_TYPE_GRABBER, -1); diff --git a/drivers/media/video/cpia2/cpia2_v4l.c b/drivers/media/video/cpia2/cpia2_v4l.c index bb4f1d0de8297..55e92902a76c6 100644 --- a/drivers/media/video/cpia2/cpia2_v4l.c +++ b/drivers/media/video/cpia2/cpia2_v4l.c @@ -1147,6 +1147,10 @@ int cpia2_register_camera(struct camera_data *cam) cam->vdev.ctrl_handler = hdl; cam->vdev.v4l2_dev = &cam->v4l2_dev; set_bit(V4L2_FL_USE_FH_PRIO, &cam->vdev.flags); + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &cam->vdev.flags); reset_camera_struct_v4l(cam); diff --git a/drivers/media/video/cx231xx/cx231xx-video.c b/drivers/media/video/cx231xx/cx231xx-video.c index 7f916f0685e9b..2a04558699f83 100644 --- a/drivers/media/video/cx231xx/cx231xx-video.c +++ b/drivers/media/video/cx231xx/cx231xx-video.c @@ -2561,6 +2561,10 @@ static struct video_device *cx231xx_vdev_init(struct cx231xx *dev, vfd->release = video_device_release; vfd->debug = video_debug; vfd->lock = &dev->lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); snprintf(vfd->name, sizeof(vfd->name), "%s %s", dev->name, type_name); diff --git a/drivers/media/video/davinci/vpbe_display.c b/drivers/media/video/davinci/vpbe_display.c index 1f3b1c7292529..e106b72810a94 100644 --- a/drivers/media/video/davinci/vpbe_display.c +++ b/drivers/media/video/davinci/vpbe_display.c @@ -1618,6 +1618,10 @@ static __devinit int init_vpbe_layer(int i, struct vpbe_display *disp_dev, vbd->ioctl_ops = &vpbe_ioctl_ops; vbd->minor = -1; vbd->v4l2_dev = &disp_dev->vpbe_dev->v4l2_dev; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vbd->flags); vbd->lock = &vpbe_display_layer->opslock; if (disp_dev->vpbe_dev->current_timings.timings_type & diff --git a/drivers/media/video/davinci/vpif_capture.c b/drivers/media/video/davinci/vpif_capture.c index 6504e40a31dd2..96046957bf21c 100644 --- a/drivers/media/video/davinci/vpif_capture.c +++ b/drivers/media/video/davinci/vpif_capture.c @@ -2228,6 +2228,10 @@ static __init int vpif_probe(struct platform_device *pdev) common = &(ch->common[VPIF_VIDEO_INDEX]); spin_lock_init(&common->irqlock); mutex_init(&common->lock); + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &ch->video_dev->flags); ch->video_dev->lock = &common->lock; /* Initialize prio member of channel object */ v4l2_prio_init(&ch->prio); diff --git a/drivers/media/video/davinci/vpif_display.c b/drivers/media/video/davinci/vpif_display.c index 7fa34b4fae26f..e6488ee7db187 100644 --- a/drivers/media/video/davinci/vpif_display.c +++ b/drivers/media/video/davinci/vpif_display.c @@ -1778,6 +1778,10 @@ static __init int vpif_probe(struct platform_device *pdev) v4l2_prio_init(&ch->prio); ch->common[VPIF_VIDEO_INDEX].fmt.type = V4L2_BUF_TYPE_VIDEO_OUTPUT; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &ch->video_dev->flags); ch->video_dev->lock = &common->lock; /* register video device */ diff --git a/drivers/media/video/em28xx/em28xx-video.c b/drivers/media/video/em28xx/em28xx-video.c index bcc41603c1931..308a1dd08cfba 100644 --- a/drivers/media/video/em28xx/em28xx-video.c +++ b/drivers/media/video/em28xx/em28xx-video.c @@ -2495,6 +2495,10 @@ static struct video_device *em28xx_vdev_init(struct em28xx *dev, vfd->release = video_device_release; vfd->debug = video_debug; vfd->lock = &dev->lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); snprintf(vfd->name, sizeof(vfd->name), "%s %s", dev->name, type_name); diff --git a/drivers/media/video/fsl-viu.c b/drivers/media/video/fsl-viu.c index 27e3e0c0b2191..777486f7cadb6 100644 --- a/drivers/media/video/fsl-viu.c +++ b/drivers/media/video/fsl-viu.c @@ -1544,6 +1544,10 @@ static int __devinit viu_of_probe(struct platform_device *op) /* initialize locks */ mutex_init(&viu_dev->lock); + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &viu_dev->vdev->flags); viu_dev->vdev->lock = &viu_dev->lock; spin_lock_init(&viu_dev->slock); diff --git a/drivers/media/video/ivtv/ivtv-streams.c b/drivers/media/video/ivtv/ivtv-streams.c index 7ea5ca7f012be..6738592aa35d6 100644 --- a/drivers/media/video/ivtv/ivtv-streams.c +++ b/drivers/media/video/ivtv/ivtv-streams.c @@ -228,6 +228,10 @@ static int ivtv_prep_dev(struct ivtv *itv, int type) s->vdev->release = video_device_release; s->vdev->tvnorms = V4L2_STD_ALL; s->vdev->lock = &itv->serialize_lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &s->vdev->flags); set_bit(V4L2_FL_USE_FH_PRIO, &s->vdev->flags); ivtv_set_funcs(s->vdev); return 0; diff --git a/drivers/media/video/mem2mem_testdev.c b/drivers/media/video/mem2mem_testdev.c index 12897e8a33145..ee3efbd83bdb1 100644 --- a/drivers/media/video/mem2mem_testdev.c +++ b/drivers/media/video/mem2mem_testdev.c @@ -958,6 +958,10 @@ static int m2mtest_probe(struct platform_device *pdev) } *vfd = m2mtest_videodev; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); vfd->lock = &dev->dev_mutex; ret = video_register_device(vfd, VFL_TYPE_GRABBER, 0); diff --git a/drivers/media/video/mx2_emmaprp.c b/drivers/media/video/mx2_emmaprp.c index 55ac1735e85b7..0bd5815de3694 100644 --- a/drivers/media/video/mx2_emmaprp.c +++ b/drivers/media/video/mx2_emmaprp.c @@ -904,6 +904,10 @@ static int emmaprp_probe(struct platform_device *pdev) } *vfd = emmaprp_videodev; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); vfd->lock = &pcdev->dev_mutex; video_set_drvdata(vfd, pcdev); diff --git a/drivers/media/video/s2255drv.c b/drivers/media/video/s2255drv.c index 37845def41c56..ea974fadb5e23 100644 --- a/drivers/media/video/s2255drv.c +++ b/drivers/media/video/s2255drv.c @@ -1948,6 +1948,10 @@ static int s2255_probe_v4l(struct s2255_dev *dev) /* register 4 video devices */ channel->vdev = template; channel->vdev.lock = &dev->lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &channel->vdev.flags); channel->vdev.v4l2_dev = &dev->v4l2_dev; video_set_drvdata(&channel->vdev, channel); if (video_nr == -1) diff --git a/drivers/media/video/s5p-fimc/fimc-capture.c b/drivers/media/video/s5p-fimc/fimc-capture.c index dc18ba510986d..72d51504ed217 100644 --- a/drivers/media/video/s5p-fimc/fimc-capture.c +++ b/drivers/media/video/s5p-fimc/fimc-capture.c @@ -1516,6 +1516,10 @@ int fimc_register_capture_device(struct fimc_dev *fimc, vfd->minor = -1; vfd->release = video_device_release; vfd->lock = &fimc->lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); video_set_drvdata(vfd, fimc); vid_cap = &fimc->vid_cap; diff --git a/drivers/media/video/s5p-fimc/fimc-core.c b/drivers/media/video/s5p-fimc/fimc-core.c index 7b90a897beebd..c58dd9f8ce67d 100644 --- a/drivers/media/video/s5p-fimc/fimc-core.c +++ b/drivers/media/video/s5p-fimc/fimc-core.c @@ -1520,6 +1520,10 @@ int fimc_register_m2m_device(struct fimc_dev *fimc, vfd->minor = -1; vfd->release = video_device_release; vfd->lock = &fimc->lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); snprintf(vfd->name, sizeof(vfd->name), "%s.m2m", dev_name(&pdev->dev)); video_set_drvdata(vfd, fimc); diff --git a/drivers/media/video/s5p-g2d/g2d.c b/drivers/media/video/s5p-g2d/g2d.c index 789de74014e51..02605cecfd65e 100644 --- a/drivers/media/video/s5p-g2d/g2d.c +++ b/drivers/media/video/s5p-g2d/g2d.c @@ -762,6 +762,10 @@ static int g2d_probe(struct platform_device *pdev) goto unreg_v4l2_dev; } *vfd = g2d_videodev; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); vfd->lock = &dev->mutex; ret = video_register_device(vfd, VFL_TYPE_GRABBER, 0); if (ret) { diff --git a/drivers/media/video/s5p-jpeg/jpeg-core.c b/drivers/media/video/s5p-jpeg/jpeg-core.c index 5a49c307f9c19..ecf7b0b04c780 100644 --- a/drivers/media/video/s5p-jpeg/jpeg-core.c +++ b/drivers/media/video/s5p-jpeg/jpeg-core.c @@ -1386,6 +1386,10 @@ static int s5p_jpeg_probe(struct platform_device *pdev) jpeg->vfd_encoder->release = video_device_release; jpeg->vfd_encoder->lock = &jpeg->lock; jpeg->vfd_encoder->v4l2_dev = &jpeg->v4l2_dev; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &jpeg->vfd_encoder->flags); ret = video_register_device(jpeg->vfd_encoder, VFL_TYPE_GRABBER, -1); if (ret) { @@ -1413,6 +1417,10 @@ static int s5p_jpeg_probe(struct platform_device *pdev) jpeg->vfd_decoder->release = video_device_release; jpeg->vfd_decoder->lock = &jpeg->lock; jpeg->vfd_decoder->v4l2_dev = &jpeg->v4l2_dev; + /* Locking in file operations other than ioctl should be done by the driver, + not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &jpeg->vfd_decoder->flags); ret = video_register_device(jpeg->vfd_decoder, VFL_TYPE_GRABBER, -1); if (ret) { diff --git a/drivers/media/video/s5p-mfc/s5p_mfc.c b/drivers/media/video/s5p-mfc/s5p_mfc.c index 83fe461af2635..76008549b3f19 100644 --- a/drivers/media/video/s5p-mfc/s5p_mfc.c +++ b/drivers/media/video/s5p-mfc/s5p_mfc.c @@ -1048,6 +1048,10 @@ static int s5p_mfc_probe(struct platform_device *pdev) vfd->ioctl_ops = get_dec_v4l2_ioctl_ops(); vfd->release = video_device_release, vfd->lock = &dev->mfc_mutex; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); vfd->v4l2_dev = &dev->v4l2_dev; snprintf(vfd->name, sizeof(vfd->name), "%s", S5P_MFC_DEC_NAME); dev->vfd_dec = vfd; @@ -1072,6 +1076,8 @@ static int s5p_mfc_probe(struct platform_device *pdev) vfd->ioctl_ops = get_enc_v4l2_ioctl_ops(); vfd->release = video_device_release, vfd->lock = &dev->mfc_mutex; + /* This should not be necessary */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); vfd->v4l2_dev = &dev->v4l2_dev; snprintf(vfd->name, sizeof(vfd->name), "%s", S5P_MFC_ENC_NAME); dev->vfd_enc = vfd; diff --git a/drivers/media/video/s5p-tv/mixer_video.c b/drivers/media/video/s5p-tv/mixer_video.c index f7ca5cc143c64..c0eadd75c9acf 100644 --- a/drivers/media/video/s5p-tv/mixer_video.c +++ b/drivers/media/video/s5p-tv/mixer_video.c @@ -1069,6 +1069,10 @@ struct mxr_layer *mxr_base_layer_create(struct mxr_device *mdev, set_bit(V4L2_FL_USE_FH_PRIO, &layer->vfd.flags); video_set_drvdata(&layer->vfd, layer); + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &layer->vfd.flags); layer->vfd.lock = &layer->mutex; layer->vfd.v4l2_dev = &mdev->v4l2_dev; diff --git a/drivers/media/video/sh_vou.c b/drivers/media/video/sh_vou.c index 9644bd861abc9..8fd1874382c65 100644 --- a/drivers/media/video/sh_vou.c +++ b/drivers/media/video/sh_vou.c @@ -1390,6 +1390,10 @@ static int __devinit sh_vou_probe(struct platform_device *pdev) vdev->v4l2_dev = &vou_dev->v4l2_dev; vdev->release = video_device_release; vdev->lock = &vou_dev->fop_lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags); vou_dev->vdev = vdev; video_set_drvdata(vdev, vou_dev); diff --git a/drivers/media/video/soc_camera.c b/drivers/media/video/soc_camera.c index eb25756a07af3..c27bb6d0a1365 100644 --- a/drivers/media/video/soc_camera.c +++ b/drivers/media/video/soc_camera.c @@ -1425,6 +1425,10 @@ static int video_dev_create(struct soc_camera_device *icd) vdev->tvnorms = V4L2_STD_UNKNOWN; vdev->ctrl_handler = &icd->ctrl_handler; vdev->lock = &icd->video_lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags); icd->vdev = vdev; diff --git a/drivers/media/video/tm6000/tm6000-video.c b/drivers/media/video/tm6000/tm6000-video.c index 1ba26d5b2ba6f..375f26abd9161 100644 --- a/drivers/media/video/tm6000/tm6000-video.c +++ b/drivers/media/video/tm6000/tm6000-video.c @@ -1731,6 +1731,10 @@ static struct video_device *vdev_init(struct tm6000_core *dev, vfd->release = video_device_release; vfd->debug = tm6000_debug; vfd->lock = &dev->lock; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags); snprintf(vfd->name, sizeof(vfd->name), "%s %s", dev->name, type_name); diff --git a/drivers/media/video/usbvision/usbvision-video.c b/drivers/media/video/usbvision/usbvision-video.c index 5a74f5e07d7dd..9bd8f084f3489 100644 --- a/drivers/media/video/usbvision/usbvision-video.c +++ b/drivers/media/video/usbvision/usbvision-video.c @@ -1296,6 +1296,10 @@ static struct video_device *usbvision_vdev_init(struct usb_usbvision *usbvision, if (NULL == vdev) return NULL; *vdev = *vdev_template; + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags); vdev->lock = &usbvision->v4l2_lock; vdev->v4l2_dev = &usbvision->v4l2_dev; snprintf(vdev->name, sizeof(vdev->name), "%s", name); diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index b1f0923212e61..2c4feffa4939a 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -274,11 +274,12 @@ static ssize_t v4l2_read(struct file *filp, char __user *buf, if (!vdev->fops->read) return -EINVAL; - if (vdev->lock && mutex_lock_interruptible(vdev->lock)) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags) && + mutex_lock_interruptible(vdev->lock)) return -ERESTARTSYS; if (video_is_registered(vdev)) ret = vdev->fops->read(filp, buf, sz, off); - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_unlock(vdev->lock); return ret; } @@ -291,11 +292,12 @@ static ssize_t v4l2_write(struct file *filp, const char __user *buf, if (!vdev->fops->write) return -EINVAL; - if (vdev->lock && mutex_lock_interruptible(vdev->lock)) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags) && + mutex_lock_interruptible(vdev->lock)) return -ERESTARTSYS; if (video_is_registered(vdev)) ret = vdev->fops->write(filp, buf, sz, off); - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_unlock(vdev->lock); return ret; } @@ -307,11 +309,11 @@ static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll) if (!vdev->fops->poll) return DEFAULT_POLLMASK; - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_lock(vdev->lock); if (video_is_registered(vdev)) ret = vdev->fops->poll(filp, poll); - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_unlock(vdev->lock); return ret; } @@ -399,11 +401,12 @@ static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm) if (!vdev->fops->mmap) return ret; - if (vdev->lock && mutex_lock_interruptible(vdev->lock)) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags) && + mutex_lock_interruptible(vdev->lock)) return -ERESTARTSYS; if (video_is_registered(vdev)) ret = vdev->fops->mmap(filp, vm); - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_unlock(vdev->lock); return ret; } @@ -426,7 +429,8 @@ static int v4l2_open(struct inode *inode, struct file *filp) video_get(vdev); mutex_unlock(&videodev_lock); if (vdev->fops->open) { - if (vdev->lock && mutex_lock_interruptible(vdev->lock)) { + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags) && + mutex_lock_interruptible(vdev->lock)) { ret = -ERESTARTSYS; goto err; } @@ -434,7 +438,7 @@ static int v4l2_open(struct inode *inode, struct file *filp) ret = vdev->fops->open(filp); else ret = -ENODEV; - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_unlock(vdev->lock); } @@ -452,10 +456,10 @@ static int v4l2_release(struct inode *inode, struct file *filp) int ret = 0; if (vdev->fops->release) { - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_lock(vdev->lock); vdev->fops->release(filp); - if (vdev->lock) + if (test_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)) mutex_unlock(vdev->lock); } /* decrease the refcount unconditionally since the release() @@ -831,6 +835,10 @@ int __video_register_device(struct video_device *vdev, int type, int nr, WARN_ON(video_device[vdev->minor] != NULL); vdev->index = get_index(vdev); mutex_unlock(&videodev_lock); + /* if no lock was passed, then make sure the LOCK_ALL_FOPS bit is + clear and warn if it wasn't. */ + if (vdev->lock == NULL) + WARN_ON(test_and_clear_bit(V4L2_FL_LOCK_ALL_FOPS, &vdev->flags)); if (vdev->ioctl_ops) determine_valid_ioctls(vdev); diff --git a/drivers/staging/media/dt3155v4l/dt3155v4l.c b/drivers/staging/media/dt3155v4l/dt3155v4l.c index 280c84ec4cc2c..c365cdf714ea5 100644 --- a/drivers/staging/media/dt3155v4l/dt3155v4l.c +++ b/drivers/staging/media/dt3155v4l/dt3155v4l.c @@ -898,6 +898,10 @@ dt3155_probe(struct pci_dev *pdev, const struct pci_device_id *id) INIT_LIST_HEAD(&pd->dmaq); mutex_init(&pd->mux); pd->vdev->lock = &pd->mux; /* for locking v4l2_file_operations */ + /* Locking in file operations other than ioctl should be done + by the driver, not the V4L2 core. + This driver needs auditing so that this flag can be removed. */ + set_bit(V4L2_FL_LOCK_ALL_FOPS, &pd->vdev->flags); spin_lock_init(&pd->lock); pd->csr2 = csr2_init; pd->config = config_init; diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h index a5ecec66d3c84..b604a7a509401 100644 --- a/include/media/v4l2-dev.h +++ b/include/media/v4l2-dev.h @@ -39,6 +39,9 @@ struct v4l2_ctrl_handler; #define V4L2_FL_USES_V4L2_FH (1) /* Use the prio field of v4l2_fh for core priority checking */ #define V4L2_FL_USE_FH_PRIO (2) +/* If ioctl core locking is in use, then apply that also to all + file operations. */ +#define V4L2_FL_LOCK_ALL_FOPS (3) /* Priority helper functions */ -- 2.30.2