[PATCH v4 17/17] iommu: Tidy the control flow in iommu_group_store_type()

Jason Gunthorpe
2023-04-12T13:52:05Z

Use a normal "goto unwind" instead of trying to be clever with checking
!ret and manually managing the unlock.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
drivers/iommu/iommu.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 85b1faac641267..bd6ad6ba80aa6a 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2944,6 +2944,7 @@ static int iommu_setup_default_domain(struct iommu_group *group,
static ssize_t iommu_group_store_type(struct iommu_group *group,
const char *buf, size_t count)
{
+ struct group_device *gdev;
int ret, req_type;

if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
@@ -2968,20 +2969,23 @@ static ssize_t iommu_group_store_type(struct iommu_group *group,
if (req_type == IOMMU_DOMAIN_DMA_FQ &&
group->default_domain->type == IOMMU_DOMAIN_DMA) {
ret = iommu_dma_init_fq(group->default_domain);
- if (!ret)
- group->default_domain->type = IOMMU_DOMAIN_DMA_FQ;
- mutex_unlock(&group->mutex);
+ if (ret)
+ goto out_unlock;

- return ret ?: count;
+ group->default_domain->type = IOMMU_DOMAIN_DMA_FQ;
+ ret = count;
+ goto out_unlock;
}

/* Otherwise, ensure that device exists and no driver is bound. */
if (list_empty(&group->devices) || group->owner_cnt) {
- mutex_unlock(&group->mutex);
- return -EPERM;
+ ret = -EPERM;
+ goto out_unlock;
}

ret = iommu_setup_default_domain(group, req_type);
+ if (ret)
+ goto out_unlock;

/*
* Release the mutex here because ops->probe_finalize() call-back of
@@ -2992,13 +2996,12 @@ static ssize_t iommu_group_store_type(struct iommu_group *group,
mutex_unlock(&group->mutex);

/* Make sure dma_ops is appropriatley set */
- if (!ret) {
- struct group_device *gdev;
-
- for_each_group_device(group, gdev)
- iommu_group_do_probe_finalize(gdev->dev);
- }
+ for_each_group_device(group, gdev)
+ iommu_group_do_probe_finalize(gdev->dev);
+ return count;

+out_unlock:
+ mutex_unlock(&group->mutex);
return ret ?: count;
}

--
2.40.0