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| author |  Lu Baolu <baolu.lu@linux.intel.com>
| 2023-03-22 14:49:54 +0800 |
|---|---|---|
| committer |  Joerg Roedel <jroedel@suse.de>
| 2023-03-22 15:45:17 +0100 |
| commit | 33793748de8fde338c11277d3d16dadc79ba65bf (patch) | |
| tree | 1affdcc3371b33aaa2238fbfcb9c4eee88d93904 /drivers/iommu/iommu.c | |
| parent | iommu: Same critical region for device release and removal (diff) | |
| download | linux-33793748de8fde338c11277d3d16dadc79ba65bf.tar.gz linux-33793748de8fde338c11277d3d16dadc79ba65bf.tar.bz2 linux-33793748de8fde338c11277d3d16dadc79ba65bf.zip | |
iommu: Move lock from iommu_change_dev_def_domain() to its caller
The intention is to make it possible to put group ownership check and
default domain change in a same critical region protected by the group's
mutex lock. No intentional functional change.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230322064956.263419-5-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/iommu.c')
| -rw-r--r-- | drivers/iommu/iommu.c | 29 |
1 files changed, 14 insertions, 15 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 419d5655ce61..32c51e6a3491 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2889,7 +2889,7 @@ static int iommu_change_dev_def_domain(struct iommu_group *group, int ret, dev_def_dom; struct device *dev; - mutex_lock(&group->mutex); + lockdep_assert_held(&group->mutex); if (group->default_domain != group->domain) { dev_err_ratelimited(prev_dev, "Group not assigned to default domain\n"); @@ -2978,28 +2978,15 @@ static int iommu_change_dev_def_domain(struct iommu_group *group, goto free_new_domain; group->domain = group->default_domain; - - /* - * Release the mutex here because ops->probe_finalize() call-back of - * some vendor IOMMU drivers calls arm_iommu_attach_device() which - * in-turn might call back into IOMMU core code, where it tries to take - * group->mutex, resulting in a deadlock. - */ - mutex_unlock(&group->mutex); - - /* Make sure dma_ops is appropriatley set */ - iommu_group_do_probe_finalize(dev, group->default_domain); iommu_domain_free(prev_dom); + return 0; free_new_domain: iommu_domain_free(group->default_domain); group->default_domain = prev_dom; group->domain = prev_dom; - out: - mutex_unlock(&group->mutex); - return ret; } @@ -3089,7 +3076,19 @@ static ssize_t iommu_group_store_type(struct iommu_group *group, goto out; } + mutex_lock(&group->mutex); ret = iommu_change_dev_def_domain(group, dev, req_type); + /* + * Release the mutex here because ops->probe_finalize() call-back of + * some vendor IOMMU drivers calls arm_iommu_attach_device() which + * in-turn might call back into IOMMU core code, where it tries to take + * group->mutex, resulting in a deadlock. + */ + mutex_unlock(&group->mutex); + + /* Make sure dma_ops is appropriatley set */ + if (!ret) + iommu_group_do_probe_finalize(dev, group->default_domain); ret = ret ?: count; out: |