mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-14 10:02:33 -04:00
Code Issues Packages Projects Releases Wiki Activity

staging: comedi: s626: tidy up freeing of the dma buffers

Browse Source 
Currently the dma buffers are freed during the detach of the driver using
the function s626_close_dma_b(). The buffers are also freed while the
interrupt handler is still attached. This could result in a race condition.

Refactor the code so that the buffers are freed after the interrupt handler
is released and the PCI device is disabled.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
H Hartley Sweeten
2014-08-25 17:55:51 -07:00
committed by Greg Kroah-Hartman
parent d558c59677
commit 3757e79559
1 changed files with 19 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

44
drivers/staging/comedi/drivers/s626.c
View File

@@ -2445,26 +2445,6 @@ static void s626_write_misc2(struct comedi_device *dev, uint16_t new_image)
s626_debi_write(dev, S626_LP_MISC1, S626_MISC1_WDISABLE);
}
static void s626_close_dma_b(struct comedi_device *dev,
struct s626_buffer_dma *pdma, size_t bsize)
{
struct pci_dev *pcidev = comedi_to_pci_dev(dev);
void *vbptr;
dma_addr_t vpptr;
if (pdma == NULL)
return;
/* find the matching allocation from the board struct */
vbptr = pdma->logical_base;
vpptr = pdma->physical_base;
if (vbptr) {
pci_free_consistent(pcidev, bsize, vbptr, vpptr);
pdma->logical_base = NULL;
pdma->physical_base = 0;
}
}
static void s626_counters_init(struct comedi_device *dev)
{
int chan;
@@ -2515,6 +2495,24 @@ static int s626_allocate_dma_buffers(struct comedi_device *dev)
return 0;
}
static void s626_free_dma_buffers(struct comedi_device *dev)
{
struct pci_dev *pcidev = comedi_to_pci_dev(dev);
struct s626_private *devpriv = dev->private;
if (!devpriv)
return;
if (devpriv->rps_buf.logical_base)
pci_free_consistent(pcidev, S626_DMABUF_SIZE,
devpriv->rps_buf.logical_base,
devpriv->rps_buf.physical_base);
if (devpriv->ana_buf.logical_base)
pci_free_consistent(pcidev, S626_DMABUF_SIZE,
devpriv->ana_buf.logical_base,
devpriv->ana_buf.physical_base);
}
static int s626_initialize(struct comedi_device *dev)
{
struct s626_private *devpriv = dev->private;
@@ -2915,11 +2913,6 @@ static void s626_detach(struct comedi_device *dev)
/* Close all interfaces on 7146 device */
writel(S626_MC1_SHUTDOWN, dev->mmio + S626_P_MC1);
writel(S626_ACON1_BASE, dev->mmio + S626_P_ACON1);
s626_close_dma_b(dev, &devpriv->rps_buf,
S626_DMABUF_SIZE);
s626_close_dma_b(dev, &devpriv->ana_buf,
S626_DMABUF_SIZE);
}
if (dev->irq)
@@ -2928,6 +2921,7 @@ static void s626_detach(struct comedi_device *dev)
iounmap(dev->mmio);
}
comedi_pci_disable(dev);
s626_free_dma_buffers(dev);
}
static struct comedi_driver s626_driver = {