Now that the IOASID allocator is in place, use it to allocate shared
PASIDs.
Signed-off-by: Jean-Philippe Brucker <jean-philippe.bruc...@arm.com>
---
drivers/iommu/Kconfig | 1 +
drivers/iommu/iommu-sva.c | 80 ++++++++++++++++++++++-----------------
2 files changed, 46 insertions(+), 35 deletions(-)
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index e89f5a97d3c4..83a62634bbc4 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -116,6 +116,7 @@ config IOMMU_SVA
bool
select IOMMU_API
select MMU_NOTIFIER
+ select IOASID
config IOMMU_PAGE_FAULT
bool
diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
index ea34e7383ab4..28eaa617b4f0 100644
--- a/drivers/iommu/iommu-sva.c
+++ b/drivers/iommu/iommu-sva.c
@@ -6,6 +6,7 @@
*/
#include <linux/idr.h>
+#include <linux/ioasid.h>
#include <linux/iommu.h>
#include <linux/mmu_notifier.h>
#include <linux/sched/mm.h>
@@ -115,12 +116,7 @@ struct iommu_bond {
void *drvdata;
};
-/*
- * Because we're using an IDR, PASIDs are limited to 31 bits (the sign bit is
- * used for returning errors). In practice implementations will use at most 20
- * bits, which is the PCI limit.
- */
-static DEFINE_IDR(iommu_pasid_idr);
+static DECLARE_IOASID_SET(ioasid_shared);
/*
* For the moment this is an all-purpose lock. It serializes
@@ -163,18 +159,13 @@ static struct io_mm *io_mm_alloc(struct device *dev,
struct mm_struct *mm,
INIT_LIST_HEAD(&io_mm->devices);
/* Leave kref as zero until the io_mm is fully initialized */
- idr_preload(GFP_KERNEL);
- spin_lock(&iommu_sva_lock);
- pasid = idr_alloc(&iommu_pasid_idr, io_mm, param->min_pasid,
- param->max_pasid + 1, GFP_ATOMIC);
- io_mm->pasid = pasid;
- spin_unlock(&iommu_sva_lock);
- idr_preload_end();
-
+ pasid = ioasid_alloc(&ioasid_shared, param->min_pasid,
+ param->max_pasid + 1, io_mm);
if (pasid < 0) {
ret = pasid;
goto err_free_mm;
}
+ io_mm->pasid = pasid;
ret = mmu_notifier_register(&io_mm->notifier, mm);
if (ret)
@@ -201,7 +192,7 @@ static struct io_mm *io_mm_alloc(struct device *dev, struct
mm_struct *mm,
* 0 so no user could get a reference to it. Free it manually.
*/
spin_lock(&iommu_sva_lock);
- idr_remove(&iommu_pasid_idr, io_mm->pasid);
+ ioasid_free(pasid);
spin_unlock(&iommu_sva_lock);
err_free_mm:
@@ -231,7 +222,7 @@ static void io_mm_release(struct kref *kref)
io_mm = container_of(kref, struct io_mm, kref);
WARN_ON(!list_empty(&io_mm->devices));
- idr_remove(&iommu_pasid_idr, io_mm->pasid);
+ ioasid_free(io_mm->pasid);
/*
* If we're being released from mm exit, the notifier callback ->release
@@ -491,15 +482,44 @@ static struct mmu_notifier_ops iommu_mmu_notifier = {
.invalidate_range = iommu_notifier_invalidate_range,
};
+struct io_mm_bond_info {
+ struct device *dev;
+ struct mm_struct *mm;
+ struct io_mm *io_mm;
+};
+
+static int io_mm_compare_bond(ioasid_t pasid, void *priv, void *data)
+{
+ struct iommu_bond *bond;
+ struct io_mm *io_mm = priv;
+ struct io_mm_bond_info *info = data;
+
+ if (io_mm->mm != info->mm || !io_mm_get_locked(io_mm))
+ /* Keep looking */
+ return 0;
+
+ /* Is it already bound to this device? */
+ list_for_each_entry(bond, &io_mm->devices, mm_head) {
+ if (bond->dev == info->dev) {
+ io_mm_put_locked(io_mm);
+ return -EEXIST;
+ }
+ }
+ info->io_mm = io_mm;
+ return 1;
+}
+
int __iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, int
*pasid,
unsigned long flags, void *drvdata)
{
- int i;
int ret = 0;
- struct iommu_bond *bond;
- struct io_mm *io_mm = NULL;
+ struct io_mm *io_mm;
struct iommu_sva_param *param;
const struct iommu_ops *ops = dev->bus->iommu_ops;
+ struct io_mm_bond_info bond_info = {
+ .dev = dev,
+ .mm = mm,
+ };
if (!ops || !dev->iommu_param)
return -ENODEV;
@@ -511,25 +531,15 @@ int __iommu_sva_bind_device(struct device *dev, struct
mm_struct *mm, int *pasid
goto out_unlock;
}
- /* If an io_mm already exists, use it */
+ /* If an io_mm already exists, get a reference and use it */
spin_lock(&iommu_sva_lock);
- idr_for_each_entry(&iommu_pasid_idr, io_mm, i) {
- if (io_mm->mm == mm && io_mm_get_locked(io_mm)) {
- /* ... Unless it's already bound to this device */
- list_for_each_entry(bond, &io_mm->devices, mm_head) {
- if (bond->dev == dev) {
- ret = -EEXIST;
- io_mm_put_locked(io_mm);
- break;
- }
- }
- break;
- }
- }
+ ret = ioasid_for_each(&ioasid_shared, io_mm_compare_bond, &bond_info);
spin_unlock(&iommu_sva_lock);
- if (ret)
+ if (ret < 0)
goto out_unlock;
+ io_mm = bond_info.io_mm;
+
/* Require identical features within an io_mm for now */
if (io_mm && (flags != io_mm->flags)) {
io_mm_put(io_mm);
@@ -640,7 +650,7 @@ struct mm_struct *iommu_sva_find(int pasid)
struct mm_struct *mm = NULL;
spin_lock(&iommu_sva_lock);
- io_mm = idr_find(&iommu_pasid_idr, pasid);
+ io_mm = ioasid_find(&ioasid_shared, pasid);
if (io_mm && io_mm_get_locked(io_mm)) {
if (mmget_not_zero(io_mm->mm))
mm = io_mm->mm;
--
2.19.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
