Re: [PATCH v2 05/12] iommu: Change the return value of dev_iommu_get()

From: Baolu Lu
Date: Thu Aug 03 2023 - 23:13:59 EST


On 2023/8/3 15:59, Tian, Kevin wrote:
From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Sent: Thursday, July 27, 2023 1:49 PM

Make dev_iommu_get() return 0 for success and error numbers for failure.
This will make the code neat and readable. No functionality changes.

Reviewed-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/iommu.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 00309f66153b..4ba3bb692993 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -290,20 +290,20 @@ void iommu_device_unregister(struct
iommu_device *iommu)
}
EXPORT_SYMBOL_GPL(iommu_device_unregister);

-static struct dev_iommu *dev_iommu_get(struct device *dev)
+static int dev_iommu_get(struct device *dev)
{
struct dev_iommu *param = dev->iommu;

if (param)
- return param;
+ return 0;

param = kzalloc(sizeof(*param), GFP_KERNEL);
if (!param)
- return NULL;
+ return -ENOMEM;

mutex_init(&param->lock);
dev->iommu = param;
- return param;
+ return 0;
}


Jason's series [1] has been queued. Time to refine according to
the discussion in [2].

[1] https://lore.kernel.org/linux-iommu/ZLFYXlSBZrlxFpHM@xxxxxxxxxx/
[2] https://lore.kernel.org/linux-iommu/c815fa2b-00df-91e1-8353-8258773957e4@xxxxxxxxxxxxxxx/

I'm not sure I understand your point here. This only changes the return
value of dev_iommu_get() to make the code more concise.

Best regards,
baolu