Commit 75dcf5dc authored by Daniel Drake's avatar Daniel Drake Committed by Stefan Richter
Browse files

video1394: remove BKL contention 



video1394 does not need to take the BKL. The data structures shared between
file_operations and interrupts are already protected through context-specific
spinlocks.

The only other danger is video1394_release() being called during another
operation, however this cannot happen because release is only ever invoked
when the last thread has closed the fd.

Signed-off-by: default avatarDaniel Drake <ddrake@brontes3d.com>
Signed-off-by: default avatarStefan Richter <stefanr@s5r6.in-berlin.de>
parent 3c21cfc4

drivers/ieee1394/video1394.c

+6 −24
Original line number Diff line number Diff line
@@ -714,7 +714,7 @@ static inline unsigned video1394_buffer_state(struct dma_iso_ctx *d, 
	return ret;

}



static int __video1394_ioctl(struct file *file,

static long video1394_ioctl(struct file *file,

			    unsigned int cmd, unsigned long arg)

{

	struct file_ctx *ctx = (struct file_ctx *)file->private_data;
@@ -1158,15 +1158,6 @@ static int __video1394_ioctl(struct file *file, 
	}

}



static long video1394_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	int err;

	lock_kernel();

	err = __video1394_ioctl(file, cmd, arg);

	unlock_kernel();

	return err;

}



/*

 *	This maps the vmalloced and reserved buffer to user space.

 *
@@ -1179,17 +1170,14 @@ static long video1394_ioctl(struct file *file, unsigned int cmd, unsigned long a 
static int video1394_mmap(struct file *file, struct vm_area_struct *vma)

{

	struct file_ctx *ctx = (struct file_ctx *)file->private_data;

	int res = -EINVAL;



	lock_kernel();

	if (ctx->current_ctx == NULL) {

		PRINT(KERN_ERR, ctx->ohci->host->id,

				"Current iso context not set");

	} else

		res = dma_region_mmap(&ctx->current_ctx->dma, file, vma);

	unlock_kernel();

		return -EINVAL;

	}



	return res;

	return dma_region_mmap(&ctx->current_ctx->dma, file, vma);

}



static unsigned int video1394_poll(struct file *file, poll_table *pt)
@@ -1200,14 +1188,12 @@ static unsigned int video1394_poll(struct file *file, poll_table *pt) 
	struct dma_iso_ctx *d;

	int i;



	lock_kernel();

	ctx = file->private_data;

	d = ctx->current_ctx;

	if (d == NULL) {

		PRINT(KERN_ERR, ctx->ohci->host->id,

				"Current iso context not set");

		mask = POLLERR;

		goto done;

		return POLLERR;

	}



	poll_wait(file, &d->waitq, pt);
@@ -1220,8 +1206,6 @@ static unsigned int video1394_poll(struct file *file, poll_table *pt) 
		}

	}

	spin_unlock_irqrestore(&d->lock, flags);

done:

	unlock_kernel();



	return mask;

}
@@ -1257,7 +1241,6 @@ static int video1394_release(struct inode *inode, struct file *file) 
	struct list_head *lh, *next;

	u64 mask;



	lock_kernel();

	list_for_each_safe(lh, next, &ctx->context_list) {

		struct dma_iso_ctx *d;

		d = list_entry(lh, struct dma_iso_ctx, link);
@@ -1278,7 +1261,6 @@ static int video1394_release(struct inode *inode, struct file *file) 
	kfree(ctx);

	file->private_data = NULL;



	unlock_kernel();

	return 0;

}

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