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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 18:50:12 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 18:50:12 +0000
commit8665bd53f2f2e27e5511d90428cb3f60e6d0ce15 (patch)
tree8d58900dc0ebd4a3011f92c128d2fe45bc7c4bf2 /drivers/iommu/iommu-sva.c
parentAdding debian version 6.7.12-1. (diff)
downloadlinux-8665bd53f2f2e27e5511d90428cb3f60e6d0ce15.tar.xz
linux-8665bd53f2f2e27e5511d90428cb3f60e6d0ce15.zip
Merging upstream version 6.8.9.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/iommu/iommu-sva.c')
-rw-r--r--drivers/iommu/iommu-sva.c112
1 files changed, 73 insertions, 39 deletions
diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
index 4a2f569974..65814cbc84 100644
--- a/drivers/iommu/iommu-sva.c
+++ b/drivers/iommu/iommu-sva.c
@@ -12,32 +12,43 @@
static DEFINE_MUTEX(iommu_sva_lock);
/* Allocate a PASID for the mm within range (inclusive) */
-static int iommu_sva_alloc_pasid(struct mm_struct *mm, struct device *dev)
+static struct iommu_mm_data *iommu_alloc_mm_data(struct mm_struct *mm, struct device *dev)
{
+ struct iommu_mm_data *iommu_mm;
ioasid_t pasid;
- int ret = 0;
+
+ lockdep_assert_held(&iommu_sva_lock);
if (!arch_pgtable_dma_compat(mm))
- return -EBUSY;
+ return ERR_PTR(-EBUSY);
- mutex_lock(&iommu_sva_lock);
+ iommu_mm = mm->iommu_mm;
/* Is a PASID already associated with this mm? */
- if (mm_valid_pasid(mm)) {
- if (mm->pasid >= dev->iommu->max_pasids)
- ret = -EOVERFLOW;
- goto out;
+ if (iommu_mm) {
+ if (iommu_mm->pasid >= dev->iommu->max_pasids)
+ return ERR_PTR(-EOVERFLOW);
+ return iommu_mm;
}
+ iommu_mm = kzalloc(sizeof(struct iommu_mm_data), GFP_KERNEL);
+ if (!iommu_mm)
+ return ERR_PTR(-ENOMEM);
+
pasid = iommu_alloc_global_pasid(dev);
if (pasid == IOMMU_PASID_INVALID) {
- ret = -ENOSPC;
- goto out;
+ kfree(iommu_mm);
+ return ERR_PTR(-ENOSPC);
}
- mm->pasid = pasid;
- ret = 0;
-out:
- mutex_unlock(&iommu_sva_lock);
- return ret;
+ iommu_mm->pasid = pasid;
+ INIT_LIST_HEAD(&iommu_mm->sva_domains);
+ INIT_LIST_HEAD(&iommu_mm->sva_handles);
+ /*
+ * Make sure the write to mm->iommu_mm is not reordered in front of
+ * initialization to iommu_mm fields. If it does, readers may see a
+ * valid iommu_mm with uninitialized values.
+ */
+ smp_store_release(&mm->iommu_mm, iommu_mm);
+ return iommu_mm;
}
/**
@@ -58,57 +69,70 @@ out:
*/
struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm)
{
+ struct iommu_mm_data *iommu_mm;
struct iommu_domain *domain;
struct iommu_sva *handle;
int ret;
+ mutex_lock(&iommu_sva_lock);
+
/* Allocate mm->pasid if necessary. */
- ret = iommu_sva_alloc_pasid(mm, dev);
- if (ret)
- return ERR_PTR(ret);
+ iommu_mm = iommu_alloc_mm_data(mm, dev);
+ if (IS_ERR(iommu_mm)) {
+ ret = PTR_ERR(iommu_mm);
+ goto out_unlock;
+ }
- handle = kzalloc(sizeof(*handle), GFP_KERNEL);
- if (!handle)
- return ERR_PTR(-ENOMEM);
+ list_for_each_entry(handle, &mm->iommu_mm->sva_handles, handle_item) {
+ if (handle->dev == dev) {
+ refcount_inc(&handle->users);
+ mutex_unlock(&iommu_sva_lock);
+ return handle;
+ }
+ }
- mutex_lock(&iommu_sva_lock);
- /* Search for an existing domain. */
- domain = iommu_get_domain_for_dev_pasid(dev, mm->pasid,
- IOMMU_DOMAIN_SVA);
- if (IS_ERR(domain)) {
- ret = PTR_ERR(domain);
+ handle = kzalloc(sizeof(*handle), GFP_KERNEL);
+ if (!handle) {
+ ret = -ENOMEM;
goto out_unlock;
}
- if (domain) {
- domain->users++;
- goto out;
+ /* Search for an existing domain. */
+ list_for_each_entry(domain, &mm->iommu_mm->sva_domains, next) {
+ ret = iommu_attach_device_pasid(domain, dev, iommu_mm->pasid);
+ if (!ret) {
+ domain->users++;
+ goto out;
+ }
}
/* Allocate a new domain and set it on device pasid. */
domain = iommu_sva_domain_alloc(dev, mm);
if (!domain) {
ret = -ENOMEM;
- goto out_unlock;
+ goto out_free_handle;
}
- ret = iommu_attach_device_pasid(domain, dev, mm->pasid);
+ ret = iommu_attach_device_pasid(domain, dev, iommu_mm->pasid);
if (ret)
goto out_free_domain;
domain->users = 1;
+ list_add(&domain->next, &mm->iommu_mm->sva_domains);
+
out:
+ refcount_set(&handle->users, 1);
+ list_add(&handle->handle_item, &mm->iommu_mm->sva_handles);
mutex_unlock(&iommu_sva_lock);
handle->dev = dev;
handle->domain = domain;
-
return handle;
out_free_domain:
iommu_domain_free(domain);
+out_free_handle:
+ kfree(handle);
out_unlock:
mutex_unlock(&iommu_sva_lock);
- kfree(handle);
-
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(iommu_sva_bind_device);
@@ -124,12 +148,19 @@ EXPORT_SYMBOL_GPL(iommu_sva_bind_device);
void iommu_sva_unbind_device(struct iommu_sva *handle)
{
struct iommu_domain *domain = handle->domain;
- ioasid_t pasid = domain->mm->pasid;
+ struct iommu_mm_data *iommu_mm = domain->mm->iommu_mm;
struct device *dev = handle->dev;
mutex_lock(&iommu_sva_lock);
+ if (!refcount_dec_and_test(&handle->users)) {
+ mutex_unlock(&iommu_sva_lock);
+ return;
+ }
+ list_del(&handle->handle_item);
+
+ iommu_detach_device_pasid(domain, dev, iommu_mm->pasid);
if (--domain->users == 0) {
- iommu_detach_device_pasid(domain, dev, pasid);
+ list_del(&domain->next);
iommu_domain_free(domain);
}
mutex_unlock(&iommu_sva_lock);
@@ -205,8 +236,11 @@ out_put_mm:
void mm_pasid_drop(struct mm_struct *mm)
{
- if (likely(!mm_valid_pasid(mm)))
+ struct iommu_mm_data *iommu_mm = mm->iommu_mm;
+
+ if (!iommu_mm)
return;
- iommu_free_global_pasid(mm->pasid);
+ iommu_free_global_pasid(iommu_mm->pasid);
+ kfree(iommu_mm);
}