diff options
author | Jason Gunthorpe <jgg@nvidia.com> | 2021-04-06 21:40:31 +0200 |
---|---|---|
committer | Alex Williamson <alex.williamson@redhat.com> | 2021-04-07 23:39:18 +0200 |
commit | fbd0e2b0c3d0b2eeaef471c9fe19ae5a7b2ee970 (patch) | |
tree | 37a1f34b243aca39f835e07edaa26c2cca1b26e9 /drivers/vfio/mdev | |
parent | vfio/mdev: Add missing reference counting to mdev_type (diff) | |
download | linux-fbd0e2b0c3d0b2eeaef471c9fe19ae5a7b2ee970.tar.xz linux-fbd0e2b0c3d0b2eeaef471c9fe19ae5a7b2ee970.zip |
vfio/mdev: Reorganize mdev_device_create()
Once the memory for the struct mdev_device is allocated it should
immediately be device_initialize()'d and filled in so that put_device()
can always be used to undo the allocation.
Place the mdev_get/put_parent() so that they are clearly protecting the
mdev->parent pointer. Move the final put to the release function so that
the lifetime rules are trivial to understand. Update the goto labels to
follow the normal convention.
Remove mdev_device_free() as the release function via device_put() is now
usable in all cases.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <8-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'drivers/vfio/mdev')
-rw-r--r-- | drivers/vfio/mdev/mdev_core.c | 60 |
1 files changed, 27 insertions, 33 deletions
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index 7ec21c907397..f7559835b061 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -71,7 +71,6 @@ static void mdev_device_remove_common(struct mdev_device *mdev) /* Balances with device_initialize() */ put_device(&mdev->dev); - mdev_put_parent(parent); } static int mdev_device_remove_cb(struct device *dev, void *data) @@ -208,8 +207,13 @@ void mdev_unregister_device(struct device *dev) } EXPORT_SYMBOL(mdev_unregister_device); -static void mdev_device_free(struct mdev_device *mdev) +static void mdev_device_release(struct device *dev) { + struct mdev_device *mdev = to_mdev_device(dev); + + /* Pairs with the get in mdev_device_create() */ + mdev_put_parent(mdev->parent); + mutex_lock(&mdev_list_lock); list_del(&mdev->next); mutex_unlock(&mdev_list_lock); @@ -218,70 +222,61 @@ static void mdev_device_free(struct mdev_device *mdev) kfree(mdev); } -static void mdev_device_release(struct device *dev) -{ - struct mdev_device *mdev = to_mdev_device(dev); - - mdev_device_free(mdev); -} - int mdev_device_create(struct mdev_type *type, const guid_t *uuid) { int ret; struct mdev_device *mdev, *tmp; struct mdev_parent *parent = type->parent; - mdev_get_parent(parent); mutex_lock(&mdev_list_lock); /* Check for duplicate */ list_for_each_entry(tmp, &mdev_list, next) { if (guid_equal(&tmp->uuid, uuid)) { mutex_unlock(&mdev_list_lock); - ret = -EEXIST; - goto mdev_fail; + return -EEXIST; } } mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); if (!mdev) { mutex_unlock(&mdev_list_lock); - ret = -ENOMEM; - goto mdev_fail; + return -ENOMEM; } + device_initialize(&mdev->dev); + mdev->dev.parent = parent->dev; + mdev->dev.bus = &mdev_bus_type; + mdev->dev.release = mdev_device_release; + mdev->dev.groups = parent->ops->mdev_attr_groups; + mdev->type = type; + mdev->parent = parent; + /* Pairs with the put in mdev_device_release() */ + mdev_get_parent(parent); + guid_copy(&mdev->uuid, uuid); list_add(&mdev->next, &mdev_list); mutex_unlock(&mdev_list_lock); - mdev->parent = parent; + dev_set_name(&mdev->dev, "%pUl", uuid); /* Check if parent unregistration has started */ if (!down_read_trylock(&parent->unreg_sem)) { - mdev_device_free(mdev); ret = -ENODEV; - goto mdev_fail; + goto out_put_device; } - device_initialize(&mdev->dev); - mdev->dev.parent = parent->dev; - mdev->dev.bus = &mdev_bus_type; - mdev->dev.release = mdev_device_release; - dev_set_name(&mdev->dev, "%pUl", uuid); - mdev->dev.groups = parent->ops->mdev_attr_groups; - mdev->type = type; - ret = parent->ops->create(&type->kobj, mdev); if (ret) - goto ops_create_fail; + goto out_unlock; ret = device_add(&mdev->dev); if (ret) - goto add_fail; + goto out_remove; ret = mdev_create_sysfs_files(mdev); if (ret) - goto sysfs_fail; + goto out_del; mdev->active = true; dev_dbg(&mdev->dev, "MDEV: created\n"); @@ -289,15 +284,14 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid) return 0; -sysfs_fail: +out_del: device_del(&mdev->dev); -add_fail: +out_remove: parent->ops->remove(mdev); -ops_create_fail: +out_unlock: up_read(&parent->unreg_sem); +out_put_device: put_device(&mdev->dev); -mdev_fail: - mdev_put_parent(parent); return ret; } |