diff options
author | Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> | 2016-03-03 13:26:47 +0100 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2016-04-14 00:12:12 +0200 |
commit | d2c1b028db2e0b153f1aff28e3010a494c8aadc1 (patch) | |
tree | 06666bac9d7a264672e460d3c8f52ba38647c4dc | |
parent | [media] v4l: vsp1: dl: Make reg_count field unsigned (diff) | |
download | linux-d2c1b028db2e0b153f1aff28e3010a494c8aadc1.tar.xz linux-d2c1b028db2e0b153f1aff28e3010a494c8aadc1.zip |
[media] v4l: vsp1: dl: Fix race conditions
The vsp1_dl_list_put() function expects to be called with the display
list manager lock held. This assumption is correct for calls from within
the vsp1_dl.c file, but not for the external calls. Fix it by taking the
lock inside the function and providing an unlocked version for the
internal callers.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
-rw-r--r-- | drivers/media/platform/vsp1/vsp1_dl.c | 41 |
1 files changed, 29 insertions, 12 deletions
diff --git a/drivers/media/platform/vsp1/vsp1_dl.c b/drivers/media/platform/vsp1/vsp1_dl.c index 51d14c4a4231..a931cced9a57 100644 --- a/drivers/media/platform/vsp1/vsp1_dl.c +++ b/drivers/media/platform/vsp1/vsp1_dl.c @@ -163,25 +163,36 @@ struct vsp1_dl_list *vsp1_dl_list_get(struct vsp1_dl_manager *dlm) return dl; } +/* This function must be called with the display list manager lock held.*/ +static void __vsp1_dl_list_put(struct vsp1_dl_list *dl) +{ + if (!dl) + return; + + dl->reg_count = 0; + + list_add_tail(&dl->list, &dl->dlm->free); +} + /** * vsp1_dl_list_put - Release a display list * @dl: The display list * * Release the display list and return it to the pool of free lists. * - * This function must be called with the display list manager lock held. - * * Passing a NULL pointer to this function is safe, in that case no operation * will be performed. */ void vsp1_dl_list_put(struct vsp1_dl_list *dl) { + unsigned long flags; + if (!dl) return; - dl->reg_count = 0; - - list_add_tail(&dl->list, &dl->dlm->free); + spin_lock_irqsave(&dl->dlm->lock, flags); + __vsp1_dl_list_put(dl); + spin_unlock_irqrestore(&dl->dlm->lock, flags); } void vsp1_dl_list_write(struct vsp1_dl_list *dl, u32 reg, u32 data) @@ -219,7 +230,7 @@ void vsp1_dl_list_commit(struct vsp1_dl_list *dl) */ update = !!(vsp1_read(vsp1, VI6_DL_BODY_SIZE) & VI6_DL_BODY_SIZE_UPD); if (update) { - vsp1_dl_list_put(dlm->pending); + __vsp1_dl_list_put(dlm->pending); dlm->pending = dl; goto done; } @@ -232,7 +243,7 @@ void vsp1_dl_list_commit(struct vsp1_dl_list *dl) vsp1_write(vsp1, VI6_DL_BODY_SIZE, VI6_DL_BODY_SIZE_UPD | (dl->reg_count * 8)); - vsp1_dl_list_put(dlm->queued); + __vsp1_dl_list_put(dlm->queued); dlm->queued = dl; done: @@ -252,7 +263,7 @@ void vsp1_dlm_irq_display_start(struct vsp1_dl_manager *dlm) * processing by the device. The active display list, if any, won't be * accessed anymore and can be reused. */ - vsp1_dl_list_put(dlm->active); + __vsp1_dl_list_put(dlm->active); dlm->active = NULL; spin_unlock(&dlm->lock); @@ -264,7 +275,7 @@ void vsp1_dlm_irq_frame_end(struct vsp1_dl_manager *dlm) spin_lock(&dlm->lock); - vsp1_dl_list_put(dlm->active); + __vsp1_dl_list_put(dlm->active); dlm->active = NULL; /* Header mode is used for mem-to-mem pipelines only. We don't need to @@ -327,9 +338,15 @@ void vsp1_dlm_setup(struct vsp1_device *vsp1) void vsp1_dlm_reset(struct vsp1_dl_manager *dlm) { - vsp1_dl_list_put(dlm->active); - vsp1_dl_list_put(dlm->queued); - vsp1_dl_list_put(dlm->pending); + unsigned long flags; + + spin_lock_irqsave(&dlm->lock, flags); + + __vsp1_dl_list_put(dlm->active); + __vsp1_dl_list_put(dlm->queued); + __vsp1_dl_list_put(dlm->pending); + + spin_unlock_irqrestore(&dlm->lock, flags); dlm->active = NULL; dlm->queued = NULL; |