[PATCH v2 0/2] PCI: switchtec: Trivial cleanups

[PATCH v2 0/2] PCI: switchtec: Trivial cleanups

[Bjorn Helgaas]

From: Bjorn Helgaas <bhelgaas@google.com>

Simplify switchtec_dma_mrpc_isr() slightly and return the right
copy_to_user() error code from switchtec_dev_read().

Bjorn Helgaas (2):
  PCI: switchtec: Simplify switchtec_dma_mrpc_isr()
  PCI: switchtec: Return -EFAULT for copy_to_user() errors

 drivers/pci/switch/switchtec.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

Changes between v1 and v2:
- Return -EFAULT for copy_to_user() errors.
-- 
2.25.1

[PATCH v2 1/2] PCI: switchtec: Simplify switchtec_dma_mrpc_isr()

[Bjorn Helgaas]

From: Bjorn Helgaas <bhelgaas@google.com>

The "ret" variable in switchtec_dma_mrpc_isr() is superfluous.  Remove it
and just return the value.  No functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
---
 drivers/pci/switch/switchtec.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
index 75be4fe22509..d7ae84070e29 100644
--- a/drivers/pci/switch/switchtec.c
+++ b/drivers/pci/switch/switchtec.c
@@ -1480,15 +1480,13 @@ static irqreturn_t switchtec_event_isr(int irq, void *dev)
 static irqreturn_t switchtec_dma_mrpc_isr(int irq, void *dev)
 {
 	struct switchtec_dev *stdev = dev;
-	irqreturn_t ret = IRQ_NONE;
 
 	iowrite32(SWITCHTEC_EVENT_CLEAR |
 		  SWITCHTEC_EVENT_EN_IRQ,
 		  &stdev->mmio_part_cfg->mrpc_comp_hdr);
 	schedule_work(&stdev->mrpc_work);
 
-	ret = IRQ_HANDLED;
-	return ret;
+	return IRQ_HANDLED;
 }
 
 static int switchtec_init_isr(struct switchtec_dev *stdev)
-- 
2.25.1

[PATCH v2 2/2] PCI: switchtec: Return -EFAULT for copy_to_user() errors

[Bjorn Helgaas]

From: Bjorn Helgaas <bhelgaas@google.com>

switchtec_dev_read() didn't handle copy_to_user() errors correctly: it
assigned "rc = -EFAULT", but actually returned either "size", -ENXIO, or
-EBADMSG instead.

Update the failure cases to unlock mrpc_mutex and return -EFAULT directly.

Fixes: 080b47def5e5 ("MicroSemi Switchtec management interface driver")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/switch/switchtec.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
index d7ae84070e29..0ac9d4488210 100644
--- a/drivers/pci/switch/switchtec.c
+++ b/drivers/pci/switch/switchtec.c
@@ -606,16 +606,16 @@ static ssize_t switchtec_dev_read(struct file *filp, char __user *data,
 	rc = copy_to_user(data, &stuser->return_code,
 			  sizeof(stuser->return_code));
 	if (rc) {
-		rc = -EFAULT;
-		goto out;
+		mutex_unlock(&stdev->mrpc_mutex);
+		return -EFAULT;
 	}
 
 	data += sizeof(stuser->return_code);
 	rc = copy_to_user(data, &stuser->data,
 			  size - sizeof(stuser->return_code));
 	if (rc) {
-		rc = -EFAULT;
-		goto out;
+		mutex_unlock(&stdev->mrpc_mutex);
+		return -EFAULT;
 	}
 
 	stuser_set_state(stuser, MRPC_IDLE);
-- 
2.25.1

Re: [PATCH v2 2/2] PCI: switchtec: Return -EFAULT for copy_to_user() errors

[Logan Gunthorpe]

On 2022-12-16 09:21, Bjorn Helgaas wrote:
> From: Bjorn Helgaas <bhelgaas@google.com>
> 
> switchtec_dev_read() didn't handle copy_to_user() errors correctly: it
> assigned "rc = -EFAULT", but actually returned either "size", -ENXIO, or
> -EBADMSG instead.
> 
> Update the failure cases to unlock mrpc_mutex and return -EFAULT directly.
> 
> Fixes: 080b47def5e5 ("MicroSemi Switchtec management interface driver")
> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Looks good to me thanks!

Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

Logan

Re: [PATCH v2 0/2] PCI: switchtec: Trivial cleanups

[Lorenzo Pieralisi]

On Fri, 16 Dec 2022 10:21:24 -0600, Bjorn Helgaas wrote:
> From: Bjorn Helgaas <bhelgaas@google.com>
> 
> Simplify switchtec_dma_mrpc_isr() slightly and return the right
> copy_to_user() error code from switchtec_dev_read().
> 
> Bjorn Helgaas (2):
>   PCI: switchtec: Simplify switchtec_dma_mrpc_isr()
>   PCI: switchtec: Return -EFAULT for copy_to_user() errors
> 
> [...]

Applied to pci/switchtec, thanks!

[1/2] PCI: switchtec: Simplify switchtec_dma_mrpc_isr()
      https://git.kernel.org/lpieralisi/pci/c/1a810b9bb681
[2/2] PCI: switchtec: Return -EFAULT for copy_to_user() errors
      https://git.kernel.org/lpieralisi/pci/c/fbc855bce49e

Thanks,
Lorenzo