From c9c31b07bab5fee3ef0bf163afc11b1100eb10d4 Mon Sep 17 00:00:00 2001 From: Dong Jia Shi Date: Wed, 12 Apr 2017 11:08:15 +0200 Subject: vfio: ccw: remove unnecessary NULL checks of a pointer Remove several unnecessary checks for the @private pointer, since it can never be NULL in these places. Reported-by: Dan Carpenter Signed-off-by: Dong Jia Shi Message-Id: <20170412090816.79108-2-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck --- drivers/s390/cio/vfio_ccw_fsm.c | 6 +----- drivers/s390/cio/vfio_ccw_ops.c | 17 ----------------- 2 files changed, 1 insertion(+), 22 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c index 55b6cc55758e..80a0559cd7ce 100644 --- a/drivers/s390/cio/vfio_ccw_fsm.c +++ b/drivers/s390/cio/vfio_ccw_fsm.c @@ -161,12 +161,8 @@ err_out: static void fsm_irq(struct vfio_ccw_private *private, enum vfio_ccw_event event) { - struct irb *irb; + struct irb *irb = this_cpu_ptr(&cio_irb); - if (!private) - return; - - irb = this_cpu_ptr(&cio_irb); memcpy(&private->irb, irb, sizeof(*irb)); queue_work(vfio_ccw_work_q, &private->io_work); diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index b2e615404034..55d0c87e73c3 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -19,9 +19,6 @@ static int vfio_ccw_mdev_reset(struct mdev_device *mdev) int ret; private = dev_get_drvdata(mdev_parent_dev(mdev)); - if (!private) - return -ENODEV; - sch = private->sch; /* * TODO: @@ -49,9 +46,6 @@ static int vfio_ccw_mdev_notifier(struct notifier_block *nb, struct vfio_ccw_private *private = container_of(nb, struct vfio_ccw_private, nb); - if (!private) - return NOTIFY_STOP; - /* * Vendor drivers MUST unpin pages in response to an * invalidation. @@ -134,9 +128,6 @@ static int vfio_ccw_mdev_remove(struct mdev_device *mdev) dev_get_drvdata(mdev_parent_dev(mdev)); int ret; - if (!private) - goto out; - if ((private->state == VFIO_CCW_STATE_NOT_OPER) || (private->state == VFIO_CCW_STATE_STANDBY)) goto out; @@ -187,9 +178,6 @@ static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev, return -EINVAL; private = dev_get_drvdata(mdev_parent_dev(mdev)); - if (!private) - return -ENODEV; - region = &private->io_region; if (copy_to_user(buf, (void *)region + *ppos, count)) return -EFAULT; @@ -209,8 +197,6 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, return -EINVAL; private = dev_get_drvdata(mdev_parent_dev(mdev)); - if (!private) - return -ENODEV; if (private->state != VFIO_CCW_STATE_IDLE) return -EACCES; @@ -274,9 +260,6 @@ static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev, return -EINVAL; private = dev_get_drvdata(mdev_parent_dev(mdev)); - if (!private) - return -ENODEV; - ctx = &private->io_trigger; switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) { -- cgit From 129cc19a94513081e9250323cd57e12ed48b3613 Mon Sep 17 00:00:00 2001 From: Dong Jia Shi Date: Wed, 12 Apr 2017 11:08:16 +0200 Subject: vfio: ccw: improve error handling for vfio_ccw_mdev_remove When vfio_ccw_mdev_reset fails during the remove process of the mdev, the current implementation simply returns. The failure indicates that the subchannel device is in a NOT_OPER state, thus the right thing to do should be removing the mdev. While we are at here, reverse the condition check to make the code more concise and readable. Signed-off-by: Dong Jia Shi Message-Id: <20170412090816.79108-3-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck --- drivers/s390/cio/vfio_ccw_ops.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 55d0c87e73c3..e72abbc18ee3 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -126,19 +126,14 @@ static int vfio_ccw_mdev_remove(struct mdev_device *mdev) { struct vfio_ccw_private *private = dev_get_drvdata(mdev_parent_dev(mdev)); - int ret; - - if ((private->state == VFIO_CCW_STATE_NOT_OPER) || - (private->state == VFIO_CCW_STATE_STANDBY)) - goto out; - - ret = vfio_ccw_mdev_reset(mdev); - if (ret) - return ret; - private->state = VFIO_CCW_STATE_STANDBY; + if ((private->state != VFIO_CCW_STATE_NOT_OPER) && + (private->state != VFIO_CCW_STATE_STANDBY)) { + if (!vfio_ccw_mdev_reset(mdev)) + private->state = VFIO_CCW_STATE_STANDBY; + /* The state will be NOT_OPER on error. */ + } -out: private->mdev = NULL; atomic_inc(&private->avail); -- cgit