From: Shashank Gupta shashank.gupta@intel.com
[ Upstream commit 1bdc85550a2b59bb7f62ead7173134e66dd2d60e ]
The sysfs `state` attribute is not protected against race conditions. If multiple processes perform a device state transition on the same device in parallel, unexpected behaviors might occur.
For transitioning the device state, adf_sysfs.c calls the functions adf_dev_init(), adf_dev_start(), adf_dev_stop() and adf_dev_shutdown() which are unprotected and interdependent on each other. To perform a state transition, these functions needs to be called in a specific order: * device up: adf_dev_init() -> adf_dev_start() * device down: adf_dev_stop() -> adf_dev_shutdown()
This change introduces the functions adf_dev_up() and adf_dev_down() which wrap the state machine functions and protect them with a per-device lock. These are then used in adf_sysfs.c instead of the individual state transition functions.
Fixes: 5ee52118ac14 ("crypto: qat - expose device state through sysfs for 4xxx") Signed-off-by: Shashank Gupta shashank.gupta@intel.com Reviewed-by: Giovanni Cabiddu giovanni.cabiddu@intel.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Sasha Levin sashal@kernel.org --- .../crypto/qat/qat_common/adf_accel_devices.h | 1 + .../crypto/qat/qat_common/adf_common_drv.h | 3 + drivers/crypto/qat/qat_common/adf_dev_mgr.c | 2 + drivers/crypto/qat/qat_common/adf_init.c | 64 +++++++++++++++++++ drivers/crypto/qat/qat_common/adf_sysfs.c | 23 +------ 5 files changed, 73 insertions(+), 20 deletions(-)
diff --git a/drivers/crypto/qat/qat_common/adf_accel_devices.h b/drivers/crypto/qat/qat_common/adf_accel_devices.h index 0a55a4f34dcfd..20f50d0e65f89 100644 --- a/drivers/crypto/qat/qat_common/adf_accel_devices.h +++ b/drivers/crypto/qat/qat_common/adf_accel_devices.h @@ -296,6 +296,7 @@ struct adf_accel_dev { u8 pf_compat_ver; } vf; }; + struct mutex state_lock; /* protect state of the device */ bool is_vf; u32 accel_id; }; diff --git a/drivers/crypto/qat/qat_common/adf_common_drv.h b/drivers/crypto/qat/qat_common/adf_common_drv.h index 7bb477c3ce25f..bff613eec5c4b 100644 --- a/drivers/crypto/qat/qat_common/adf_common_drv.h +++ b/drivers/crypto/qat/qat_common/adf_common_drv.h @@ -58,6 +58,9 @@ void adf_dev_stop(struct adf_accel_dev *accel_dev); void adf_dev_shutdown(struct adf_accel_dev *accel_dev); int adf_dev_shutdown_cache_cfg(struct adf_accel_dev *accel_dev);
+int adf_dev_up(struct adf_accel_dev *accel_dev, bool init_config); +int adf_dev_down(struct adf_accel_dev *accel_dev, bool cache_config); + void adf_devmgr_update_class_index(struct adf_hw_device_data *hw_data); void adf_clean_vf_map(bool);
diff --git a/drivers/crypto/qat/qat_common/adf_dev_mgr.c b/drivers/crypto/qat/qat_common/adf_dev_mgr.c index 4c752eed10fea..86ee36feefad3 100644 --- a/drivers/crypto/qat/qat_common/adf_dev_mgr.c +++ b/drivers/crypto/qat/qat_common/adf_dev_mgr.c @@ -223,6 +223,7 @@ int adf_devmgr_add_dev(struct adf_accel_dev *accel_dev, map->attached = true; list_add_tail(&map->list, &vfs_table); } + mutex_init(&accel_dev->state_lock); unlock: mutex_unlock(&table_lock); return ret; @@ -269,6 +270,7 @@ void adf_devmgr_rm_dev(struct adf_accel_dev *accel_dev, } } unlock: + mutex_destroy(&accel_dev->state_lock); list_del(&accel_dev->list); mutex_unlock(&table_lock); } diff --git a/drivers/crypto/qat/qat_common/adf_init.c b/drivers/crypto/qat/qat_common/adf_init.c index 33a9a46d69494..d6f3314246179 100644 --- a/drivers/crypto/qat/qat_common/adf_init.c +++ b/drivers/crypto/qat/qat_common/adf_init.c @@ -389,3 +389,67 @@ int adf_dev_shutdown_cache_cfg(struct adf_accel_dev *accel_dev)
return 0; } + +int adf_dev_down(struct adf_accel_dev *accel_dev, bool reconfig) +{ + int ret = 0; + + if (!accel_dev) + return -EINVAL; + + mutex_lock(&accel_dev->state_lock); + + if (!adf_dev_started(accel_dev)) { + dev_info(&GET_DEV(accel_dev), "Device qat_dev%d already down\n", + accel_dev->accel_id); + ret = -EINVAL; + goto out; + } + + if (reconfig) { + ret = adf_dev_shutdown_cache_cfg(accel_dev); + goto out; + } + + adf_dev_stop(accel_dev); + adf_dev_shutdown(accel_dev); + +out: + mutex_unlock(&accel_dev->state_lock); + return ret; +} +EXPORT_SYMBOL_GPL(adf_dev_down); + +int adf_dev_up(struct adf_accel_dev *accel_dev, bool config) +{ + int ret = 0; + + if (!accel_dev) + return -EINVAL; + + mutex_lock(&accel_dev->state_lock); + + if (adf_dev_started(accel_dev)) { + dev_info(&GET_DEV(accel_dev), "Device qat_dev%d already up\n", + accel_dev->accel_id); + ret = -EALREADY; + goto out; + } + + if (config && GET_HW_DATA(accel_dev)->dev_config) { + ret = GET_HW_DATA(accel_dev)->dev_config(accel_dev); + if (unlikely(ret)) + goto out; + } + + ret = adf_dev_init(accel_dev); + if (unlikely(ret)) + goto out; + + ret = adf_dev_start(accel_dev); + +out: + mutex_unlock(&accel_dev->state_lock); + return ret; +} +EXPORT_SYMBOL_GPL(adf_dev_up); diff --git a/drivers/crypto/qat/qat_common/adf_sysfs.c b/drivers/crypto/qat/qat_common/adf_sysfs.c index e8b078e719c20..3eb6611ab1b11 100644 --- a/drivers/crypto/qat/qat_common/adf_sysfs.c +++ b/drivers/crypto/qat/qat_common/adf_sysfs.c @@ -50,38 +50,21 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
switch (ret) { case DEV_DOWN: - if (!adf_dev_started(accel_dev)) { - dev_info(dev, "Device qat_dev%d already down\n", - accel_id); - return -EINVAL; - } - dev_info(dev, "Stopping device qat_dev%d\n", accel_id);
- ret = adf_dev_shutdown_cache_cfg(accel_dev); + ret = adf_dev_down(accel_dev, true); if (ret < 0) return -EINVAL;
break; case DEV_UP: - if (adf_dev_started(accel_dev)) { - dev_info(dev, "Device qat_dev%d already up\n", - accel_id); - return -EINVAL; - } - dev_info(dev, "Starting device qat_dev%d\n", accel_id);
- ret = GET_HW_DATA(accel_dev)->dev_config(accel_dev); - if (!ret) - ret = adf_dev_init(accel_dev); - if (!ret) - ret = adf_dev_start(accel_dev); - + ret = adf_dev_up(accel_dev, true); if (ret < 0) { dev_err(dev, "Failed to start device qat_dev%d\n", accel_id); - adf_dev_shutdown_cache_cfg(accel_dev); + adf_dev_down(accel_dev, true); return ret; } break;