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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: Daniel Drake <ddrake@brontes3d.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This commit is contained in:
Daniel Drake 2006-10-20 14:56:01 +01:00 committed by Stefan Richter
parent 3c21cfc4ba
commit 75dcf5dc5a
1 changed files with 6 additions and 24 deletions
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30
drivers/ieee1394/video1394.c
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@ -714,8 +714,8 @@ static inline unsigned video1394_buffer_state(struct dma_iso_ctx *d,
return ret;
}
static int __video1394_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
static long video1394_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
{
struct file_ctx *ctx = (struct file_ctx *)file->private_data;
struct ti_ohci *ohci = ctx->ohci;
@ -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;
}