* [PATCH 1/3] iommufd: Add devices_users to track the hw_pagetable usage by device
2023-01-28 2:29 [PATCH 0/3] iommufd: Remove iommufd_hw_pagetable_has_group Nicolin Chen
@ 2023-01-28 2:29 ` Nicolin Chen
2023-01-28 2:29 ` [PATCH 2/3] iommufd/device: Make hwpt_list list_add/del symmetric Nicolin Chen
2023-01-28 2:29 ` [PATCH 3/3] iommufd/device: Change iommufd_hw_pagetable_has_group to device centric Nicolin Chen
2 siblings, 0 replies; 6+ messages in thread
From: Nicolin Chen @ 2023-01-28 2:29 UTC (permalink / raw)
To: jgg, kevin.tian; +Cc: yi.l.liu, iommu, linux-kernel
From: Yi Liu <yi.l.liu@intel.com>
Currently, hw_pagetable tracks the attached devices using a device list.
When attaching the first device to the kernel-managed hw_pagetable, it
should be linked to IOAS. When detaching the last device from this hwpt,
the link with IOAS should be removed too. And this first-or-last device
check is done with list_empty(hwpt->devices).
However, with a nested configuration, when a device is attached to the
user-managed stage-1 hw_pagetable, it will be added to this user-managed
hwpt's device list instead of the kernel-managed stage-2 hwpt's one. And
this breaks the logic for a kernel-managed hw_pagetable link/disconnect
to/from IOAS/IOPT. e.g. the stage-2 hw_pagetable would be linked to IOAS
multiple times if multiple device is attached, but it will become empty
as soon as one device detached.
Add a devices_users in struct iommufd_hw_pagetable to track the users of
hw_pagetable by the attached devices. Make this field as a pointer, only
allocate for a stage-2 hw_pagetable. A stage-1 hw_pagetable should reuse
the stage-2 hw_pagetable's devices_users, because when a device attaches
to a stage-1 hw_pagetable, linking the stage-2 hwpt to the IOAS is still
required. So, with a nested configuration, increase the devices_users on
the stage-2 (parent) hwpt, no matter a device is attached to the stage-1
or the stage-2 hwpt.
Adding this devices_users also reduces the dependency on the device list,
so it helps the following patch to remove the device list completely.
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Co-developed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/iommufd/device.c | 8 +++++---
drivers/iommu/iommufd/hw_pagetable.c | 11 +++++++++++
drivers/iommu/iommufd/iommufd_private.h | 1 +
3 files changed, 17 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index 9f3b9674d72e..208757c39c90 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -212,7 +212,7 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
hwpt->domain->ops->enforce_cache_coherency(
hwpt->domain);
if (!hwpt->enforce_cache_coherency) {
- WARN_ON(list_empty(&hwpt->devices));
+ WARN_ON(refcount_read(hwpt->devices_users) == 1);
rc = -EINVAL;
goto out_unlock;
}
@@ -236,7 +236,7 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
if (rc)
goto out_iova;
- if (list_empty(&hwpt->devices)) {
+ if (refcount_read(hwpt->devices_users) == 1) {
rc = iopt_table_add_domain(&hwpt->ioas->iopt,
hwpt->domain);
if (rc)
@@ -246,6 +246,7 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
idev->hwpt = hwpt;
refcount_inc(&hwpt->obj.users);
+ refcount_inc(hwpt->devices_users);
list_add(&idev->devices_item, &hwpt->devices);
mutex_unlock(&hwpt->devices_lock);
return 0;
@@ -387,9 +388,10 @@ void iommufd_device_detach(struct iommufd_device *idev)
mutex_lock(&hwpt->ioas->mutex);
mutex_lock(&hwpt->devices_lock);
+ refcount_dec(hwpt->devices_users);
list_del(&idev->devices_item);
if (!iommufd_hw_pagetable_has_group(hwpt, idev->group)) {
- if (list_empty(&hwpt->devices)) {
+ if (refcount_read(hwpt->devices_users) == 1) {
iopt_table_remove_domain(&hwpt->ioas->iopt,
hwpt->domain);
list_del(&hwpt->hwpt_item);
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index 43d473989a06..910e759ffeac 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -16,6 +16,8 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj)
iommu_domain_free(hwpt->domain);
refcount_dec(&hwpt->ioas->obj.users);
mutex_destroy(&hwpt->devices_lock);
+ WARN_ON(!refcount_dec_if_one(hwpt->devices_users));
+ kfree(hwpt->devices_users);
}
/**
@@ -46,11 +48,20 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
INIT_LIST_HEAD(&hwpt->devices);
INIT_LIST_HEAD(&hwpt->hwpt_item);
mutex_init(&hwpt->devices_lock);
+ hwpt->devices_users = kzalloc(sizeof(*hwpt->devices_users), GFP_KERNEL);
+ if (!hwpt->devices_users) {
+ rc = -ENOMEM;
+ goto out_free_domain;
+ }
+ refcount_set(hwpt->devices_users, 1);
+
/* Pairs with iommufd_hw_pagetable_destroy() */
refcount_inc(&ioas->obj.users);
hwpt->ioas = ioas;
return hwpt;
+out_free_domain:
+ iommu_domain_free(hwpt->domain);
out_abort:
iommufd_object_abort(ictx, &hwpt->obj);
return ERR_PTR(rc);
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 222e86591f8a..f128d77fb076 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -247,6 +247,7 @@ struct iommufd_hw_pagetable {
/* Head at iommufd_ioas::hwpt_list */
struct list_head hwpt_item;
struct mutex devices_lock;
+ refcount_t *devices_users;
struct list_head devices;
};
--
2.39.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 2/3] iommufd/device: Make hwpt_list list_add/del symmetric
2023-01-28 2:29 [PATCH 0/3] iommufd: Remove iommufd_hw_pagetable_has_group Nicolin Chen
2023-01-28 2:29 ` [PATCH 1/3] iommufd: Add devices_users to track the hw_pagetable usage by device Nicolin Chen
@ 2023-01-28 2:29 ` Nicolin Chen
2023-01-28 11:52 ` kernel test robot
2023-01-28 2:29 ` [PATCH 3/3] iommufd/device: Change iommufd_hw_pagetable_has_group to device centric Nicolin Chen
2 siblings, 1 reply; 6+ messages in thread
From: Nicolin Chen @ 2023-01-28 2:29 UTC (permalink / raw)
To: jgg, kevin.tian; +Cc: yi.l.liu, iommu, linux-kernel
Since the list_del() of hwpt_item is done in iommufd_device_detach(), move
its list_add_tail() to a similar place in iommufd_device_do_attach().
Also move and place the mutex outside the iommufd_device_auto_get_domain()
and iommufd_device_do_attach() calls, to serialize attach/detach routines.
This adds an additional locking protection so that the following patch can
safely remove devices_lock.
Co-developed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/iommufd/device.c | 26 ++++++++++++--------------
1 file changed, 12 insertions(+), 14 deletions(-)
diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index 208757c39c90..0248073e3169 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -198,6 +198,8 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
phys_addr_t sw_msi_start = PHYS_ADDR_MAX;
int rc;
+ lockdep_assert_held(&hwpt->ioas->mutex);
+
mutex_lock(&hwpt->devices_lock);
/*
@@ -241,6 +243,7 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
hwpt->domain);
if (rc)
goto out_detach;
+ list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list);
}
}
@@ -271,12 +274,13 @@ static int iommufd_device_auto_get_domain(struct iommufd_device *idev,
struct iommufd_hw_pagetable *hwpt;
int rc;
+ lockdep_assert_held(&hwpt->ioas->mutex);
+
/*
* There is no differentiation when domains are allocated, so any domain
* that is willing to attach to the device is interchangeable with any
* other.
*/
- mutex_lock(&ioas->mutex);
list_for_each_entry(hwpt, &ioas->hwpt_list, hwpt_item) {
if (!hwpt->auto_domain)
continue;
@@ -290,29 +294,23 @@ static int iommufd_device_auto_get_domain(struct iommufd_device *idev,
*/
if (rc == -EINVAL)
continue;
- goto out_unlock;
+ return rc;
}
hwpt = iommufd_hw_pagetable_alloc(idev->ictx, ioas, idev->dev);
- if (IS_ERR(hwpt)) {
- rc = PTR_ERR(hwpt);
- goto out_unlock;
- }
+ if (IS_ERR(hwpt))
+ return PTR_ERR(hwpt);
hwpt->auto_domain = true;
rc = iommufd_device_do_attach(idev, hwpt);
if (rc)
goto out_abort;
- list_add_tail(&hwpt->hwpt_item, &ioas->hwpt_list);
- mutex_unlock(&ioas->mutex);
iommufd_object_finalize(idev->ictx, &hwpt->obj);
return 0;
out_abort:
iommufd_object_abort_and_destroy(idev->ictx, &hwpt->obj);
-out_unlock:
- mutex_unlock(&ioas->mutex);
return rc;
}
@@ -342,20 +340,20 @@ int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id)
struct iommufd_hw_pagetable *hwpt =
container_of(pt_obj, struct iommufd_hw_pagetable, obj);
+ mutex_lock(&hwpt->ioas->mutex);
rc = iommufd_device_do_attach(idev, hwpt);
+ mutex_unlock(&hwpt->ioas->mutex);
if (rc)
goto out_put_pt_obj;
-
- mutex_lock(&hwpt->ioas->mutex);
- list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list);
- mutex_unlock(&hwpt->ioas->mutex);
break;
}
case IOMMUFD_OBJ_IOAS: {
struct iommufd_ioas *ioas =
container_of(pt_obj, struct iommufd_ioas, obj);
+ mutex_lock(&ioas->mutex);
rc = iommufd_device_auto_get_domain(idev, ioas);
+ mutex_unlock(&ioas->mutex);
if (rc)
goto out_put_pt_obj;
break;
--
2.39.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH 2/3] iommufd/device: Make hwpt_list list_add/del symmetric
2023-01-28 2:29 ` [PATCH 2/3] iommufd/device: Make hwpt_list list_add/del symmetric Nicolin Chen
@ 2023-01-28 11:52 ` kernel test robot
2023-01-28 20:27 ` Nicolin Chen
0 siblings, 1 reply; 6+ messages in thread
From: kernel test robot @ 2023-01-28 11:52 UTC (permalink / raw)
To: Nicolin Chen, jgg, kevin.tian
Cc: llvm, oe-kbuild-all, yi.l.liu, iommu, linux-kernel
Hi Nicolin,
I love your patch! Perhaps something to improve:
[auto build test WARNING on v6.2-rc5]
[also build test WARNING on linus/master next-20230127]
[cannot apply to joro-iommu/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Nicolin-Chen/iommufd-Add-devices_users-to-track-the-hw_pagetable-usage-by-device/20230128-150429
patch link: https://lore.kernel.org/r/25b3b85b03fc2a7968c476b0533f451acecdfd13.1674872884.git.nicolinc%40nvidia.com
patch subject: [PATCH 2/3] iommufd/device: Make hwpt_list list_add/del symmetric
config: x86_64-randconfig-a011-20230123 (https://download.01.org/0day-ci/archive/20230128/202301281943.Jdvwci2p-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/4d48fdd86375f6d888bbcf830a10c48720008955
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Nicolin-Chen/iommufd-Add-devices_users-to-track-the-hw_pagetable-usage-by-device/20230128-150429
git checkout 4d48fdd86375f6d888bbcf830a10c48720008955
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/iommu/iommufd/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> drivers/iommu/iommufd/device.c:279:23: warning: variable 'hwpt' is uninitialized when used here [-Wuninitialized]
lockdep_assert_held(&hwpt->ioas->mutex);
^~~~
include/linux/lockdep.h:319:33: note: expanded from macro 'lockdep_assert_held'
lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
^
include/linux/lockdep.h:286:47: note: expanded from macro 'lockdep_is_held'
#define lockdep_is_held(lock) lock_is_held(&(lock)->dep_map)
^~~~
include/linux/lockdep.h:313:32: note: expanded from macro 'lockdep_assert'
do { WARN_ON(debug_locks && !(cond)); } while (0)
^~~~
include/asm-generic/bug.h:122:25: note: expanded from macro 'WARN_ON'
int __ret_warn_on = !!(condition); \
^~~~~~~~~
drivers/iommu/iommufd/device.c:276:35: note: initialize the variable 'hwpt' to silence this warning
struct iommufd_hw_pagetable *hwpt;
^
= NULL
1 warning generated.
vim +/hwpt +279 drivers/iommu/iommufd/device.c
267
268 /*
269 * When automatically managing the domains we search for a compatible domain in
270 * the iopt and if one is found use it, otherwise create a new domain.
271 * Automatic domain selection will never pick a manually created domain.
272 */
273 static int iommufd_device_auto_get_domain(struct iommufd_device *idev,
274 struct iommufd_ioas *ioas)
275 {
276 struct iommufd_hw_pagetable *hwpt;
277 int rc;
278
> 279 lockdep_assert_held(&hwpt->ioas->mutex);
280
281 /*
282 * There is no differentiation when domains are allocated, so any domain
283 * that is willing to attach to the device is interchangeable with any
284 * other.
285 */
286 list_for_each_entry(hwpt, &ioas->hwpt_list, hwpt_item) {
287 if (!hwpt->auto_domain)
288 continue;
289
290 rc = iommufd_device_do_attach(idev, hwpt);
291
292 /*
293 * -EINVAL means the domain is incompatible with the device.
294 * Other error codes should propagate to userspace as failure.
295 * Success means the domain is attached.
296 */
297 if (rc == -EINVAL)
298 continue;
299 return rc;
300 }
301
302 hwpt = iommufd_hw_pagetable_alloc(idev->ictx, ioas, idev->dev);
303 if (IS_ERR(hwpt))
304 return PTR_ERR(hwpt);
305 hwpt->auto_domain = true;
306
307 rc = iommufd_device_do_attach(idev, hwpt);
308 if (rc)
309 goto out_abort;
310
311 iommufd_object_finalize(idev->ictx, &hwpt->obj);
312 return 0;
313
314 out_abort:
315 iommufd_object_abort_and_destroy(idev->ictx, &hwpt->obj);
316 return rc;
317 }
318
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH 2/3] iommufd/device: Make hwpt_list list_add/del symmetric
2023-01-28 11:52 ` kernel test robot
@ 2023-01-28 20:27 ` Nicolin Chen
0 siblings, 0 replies; 6+ messages in thread
From: Nicolin Chen @ 2023-01-28 20:27 UTC (permalink / raw)
To: jgg, kevin.tian, kernel test robot
Cc: llvm, oe-kbuild-all, yi.l.liu, iommu, linux-kernel
On Sat, Jan 28, 2023 at 07:52:54PM +0800, kernel test robot wrote:
> >> drivers/iommu/iommufd/device.c:279:23: warning: variable 'hwpt' is uninitialized when used here [-Wuninitialized]
> lockdep_assert_held(&hwpt->ioas->mutex);
> ^~~~
A mistake here...will fix with a v2:
lockdep_assert_held(&ioas->mutex);
Thanks
Nicolin
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 3/3] iommufd/device: Change iommufd_hw_pagetable_has_group to device centric
2023-01-28 2:29 [PATCH 0/3] iommufd: Remove iommufd_hw_pagetable_has_group Nicolin Chen
2023-01-28 2:29 ` [PATCH 1/3] iommufd: Add devices_users to track the hw_pagetable usage by device Nicolin Chen
2023-01-28 2:29 ` [PATCH 2/3] iommufd/device: Make hwpt_list list_add/del symmetric Nicolin Chen
@ 2023-01-28 2:29 ` Nicolin Chen
2 siblings, 0 replies; 6+ messages in thread
From: Nicolin Chen @ 2023-01-28 2:29 UTC (permalink / raw)
To: jgg, kevin.tian; +Cc: yi.l.liu, iommu, linux-kernel
The iommufd_hw_pagetable_has_group() is a little hack to check whether
a hw_pagetable has an idev->group attached. This isn't device-centric
firstly, but also requires the hw_pagetable to maintain a device list
with a devices_lock, which gets overcomplicated among the routines for
different use cases, upcoming nested hwpts especially.
Since we can compare the iommu_group->domain and the hwpt->domain to
serve the same purpose while being device centric, change it and drop
the device list with the devices_lock accordingly.
Note that, in the detach routine, it previously checked !has_group as
there was a list_del on the device list. But now, the device is still
being attached to the hwpt, so the if logic gets inverted.
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/iommufd/device.c | 40 ++++++++-----------------
drivers/iommu/iommufd/hw_pagetable.c | 5 ----
drivers/iommu/iommufd/iommufd_private.h | 2 --
3 files changed, 12 insertions(+), 35 deletions(-)
diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index 0248073e3169..5a5dfc0c4ca0 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -24,8 +24,6 @@ struct iommufd_device {
struct iommufd_object obj;
struct iommufd_ctx *ictx;
struct iommufd_hw_pagetable *hwpt;
- /* Head at iommufd_hw_pagetable::devices */
- struct list_head devices_item;
/* always the physical device */
struct device *dev;
struct iommu_group *group;
@@ -181,15 +179,15 @@ static int iommufd_device_setup_msi(struct iommufd_device *idev,
return 0;
}
-static bool iommufd_hw_pagetable_has_group(struct iommufd_hw_pagetable *hwpt,
- struct iommu_group *group)
+static bool iommufd_hw_pagetable_has_device(struct iommufd_hw_pagetable *hwpt,
+ struct device *dev)
{
- struct iommufd_device *cur_dev;
-
- list_for_each_entry(cur_dev, &hwpt->devices, devices_item)
- if (cur_dev->group == group)
- return true;
- return false;
+ /*
+ * iommu_get_domain_for_dev() returns an iommu_group->domain ptr, if it
+ * is the same domain as the hwpt->domain, it means that this hwpt has
+ * the iommu_group/device.
+ */
+ return hwpt->domain == iommu_get_domain_for_dev(dev);
}
static int iommufd_device_do_attach(struct iommufd_device *idev,
@@ -200,8 +198,6 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
lockdep_assert_held(&hwpt->ioas->mutex);
- mutex_lock(&hwpt->devices_lock);
-
/*
* Try to upgrade the domain we have, it is an iommu driver bug to
* report IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail
@@ -215,25 +211,20 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
hwpt->domain);
if (!hwpt->enforce_cache_coherency) {
WARN_ON(refcount_read(hwpt->devices_users) == 1);
- rc = -EINVAL;
- goto out_unlock;
+ return -EINVAL;
}
}
rc = iopt_table_enforce_group_resv_regions(&hwpt->ioas->iopt, idev->dev,
idev->group, &sw_msi_start);
if (rc)
- goto out_unlock;
+ return rc;
rc = iommufd_device_setup_msi(idev, hwpt, sw_msi_start);
if (rc)
goto out_iova;
- /*
- * FIXME: Hack around missing a device-centric iommu api, only attach to
- * the group once for the first device that is in the group.
- */
- if (!iommufd_hw_pagetable_has_group(hwpt, idev->group)) {
+ if (!iommufd_hw_pagetable_has_device(hwpt, idev->dev)) {
rc = iommu_attach_group(hwpt->domain, idev->group);
if (rc)
goto out_iova;
@@ -250,16 +241,12 @@ static int iommufd_device_do_attach(struct iommufd_device *idev,
idev->hwpt = hwpt;
refcount_inc(&hwpt->obj.users);
refcount_inc(hwpt->devices_users);
- list_add(&idev->devices_item, &hwpt->devices);
- mutex_unlock(&hwpt->devices_lock);
return 0;
out_detach:
iommu_detach_group(hwpt->domain, idev->group);
out_iova:
iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev);
-out_unlock:
- mutex_unlock(&hwpt->devices_lock);
return rc;
}
@@ -385,10 +372,8 @@ void iommufd_device_detach(struct iommufd_device *idev)
struct iommufd_hw_pagetable *hwpt = idev->hwpt;
mutex_lock(&hwpt->ioas->mutex);
- mutex_lock(&hwpt->devices_lock);
refcount_dec(hwpt->devices_users);
- list_del(&idev->devices_item);
- if (!iommufd_hw_pagetable_has_group(hwpt, idev->group)) {
+ if (iommufd_hw_pagetable_has_device(hwpt, idev->dev)) {
if (refcount_read(hwpt->devices_users) == 1) {
iopt_table_remove_domain(&hwpt->ioas->iopt,
hwpt->domain);
@@ -397,7 +382,6 @@ void iommufd_device_detach(struct iommufd_device *idev)
iommu_detach_group(hwpt->domain, idev->group);
}
iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev);
- mutex_unlock(&hwpt->devices_lock);
mutex_unlock(&hwpt->ioas->mutex);
if (hwpt->auto_domain)
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index 910e759ffeac..868a126ff37d 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -11,11 +11,8 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj)
struct iommufd_hw_pagetable *hwpt =
container_of(obj, struct iommufd_hw_pagetable, obj);
- WARN_ON(!list_empty(&hwpt->devices));
-
iommu_domain_free(hwpt->domain);
refcount_dec(&hwpt->ioas->obj.users);
- mutex_destroy(&hwpt->devices_lock);
WARN_ON(!refcount_dec_if_one(hwpt->devices_users));
kfree(hwpt->devices_users);
}
@@ -45,9 +42,7 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
goto out_abort;
}
- INIT_LIST_HEAD(&hwpt->devices);
INIT_LIST_HEAD(&hwpt->hwpt_item);
- mutex_init(&hwpt->devices_lock);
hwpt->devices_users = kzalloc(sizeof(*hwpt->devices_users), GFP_KERNEL);
if (!hwpt->devices_users) {
rc = -ENOMEM;
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index f128d77fb076..1c8e59b37f46 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -246,9 +246,7 @@ struct iommufd_hw_pagetable {
bool msi_cookie : 1;
/* Head at iommufd_ioas::hwpt_list */
struct list_head hwpt_item;
- struct mutex devices_lock;
refcount_t *devices_users;
- struct list_head devices;
};
struct iommufd_hw_pagetable *
--
2.39.1
^ permalink raw reply related [flat|nested] 6+ messages in thread