This patch refactor's the vfio_ap device driver to use the AP bus's
ap_get_qdev() function to retrieve the vfio_ap_queue struct containing
information about a queue that is bound to the vfio_ap device driver.
The bus's ap_get_qdev() function retrieves the queue device from a
hashtable keyed by APQN. This is much more efficient than looping over
the list of devices attached to the AP bus by several orders of
magnitude.
Signed-off-by: Tony Krowiak <[email protected]>
---
drivers/s390/crypto/vfio_ap_drv.c | 27 ++-------
drivers/s390/crypto/vfio_ap_ops.c | 82 +++++++++++++++------------
drivers/s390/crypto/vfio_ap_private.h | 8 ++-
3 files changed, 58 insertions(+), 59 deletions(-)
diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
index be2520cc010b..59233cf7419d 100644
--- a/drivers/s390/crypto/vfio_ap_drv.c
+++ b/drivers/s390/crypto/vfio_ap_drv.c
@@ -51,15 +51,9 @@ MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids);
*/
static int vfio_ap_queue_dev_probe(struct ap_device *apdev)
{
- struct vfio_ap_queue *q;
-
- q = kzalloc(sizeof(*q), GFP_KERNEL);
- if (!q)
- return -ENOMEM;
- dev_set_drvdata(&apdev->device, q);
- q->apqn = to_ap_queue(&apdev->device)->qid;
- q->saved_isc = VFIO_AP_ISC_INVALID;
- return 0;
+ struct ap_queue *queue = to_ap_queue(&apdev->device);
+
+ return vfio_ap_mdev_probe_queue(queue);
}
/**
@@ -70,18 +64,9 @@ static int vfio_ap_queue_dev_probe(struct ap_device *apdev)
*/
static void vfio_ap_queue_dev_remove(struct ap_device *apdev)
{
- struct vfio_ap_queue *q;
- int apid, apqi;
-
- mutex_lock(&matrix_dev->lock);
- q = dev_get_drvdata(&apdev->device);
- dev_set_drvdata(&apdev->device, NULL);
- apid = AP_QID_CARD(q->apqn);
- apqi = AP_QID_QUEUE(q->apqn);
- vfio_ap_mdev_reset_queue(apid, apqi, 1);
- vfio_ap_irq_disable(q);
- kfree(q);
- mutex_unlock(&matrix_dev->lock);
+ struct ap_queue *queue = to_ap_queue(&apdev->device);
+
+ vfio_ap_mdev_remove_queue(queue);
}
static void vfio_ap_matrix_dev_release(struct device *dev)
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index e0bde8518745..7c96b6fd9f70 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -26,43 +26,26 @@
static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev);
-static int match_apqn(struct device *dev, const void *data)
-{
- struct vfio_ap_queue *q = dev_get_drvdata(dev);
-
- return (q->apqn == *(int *)(data)) ? 1 : 0;
-}
-
/**
- * vfio_ap_get_queue: Retrieve a queue with a specific APQN from a list
- * @matrix_mdev: the associated mediated matrix
+ * vfio_ap_get_queue: Retrieve a queue with a specific APQN.
* @apqn: The queue APQN
*
- * Retrieve a queue with a specific APQN from the list of the
- * devices of the vfio_ap_drv.
- * Verify that the APID and the APQI are set in the matrix.
+ * Retrieve a queue with a specific APQN from the AP queue devices attached to
+ * the AP bus.
*
- * Returns the pointer to the associated vfio_ap_queue
+ * Returns the pointer to the vfio_ap_queue with the specified APQN, or NULL.
*/
-static struct vfio_ap_queue *vfio_ap_get_queue(
- struct ap_matrix_mdev *matrix_mdev,
- int apqn)
+static struct vfio_ap_queue *vfio_ap_get_queue(unsigned long apqn)
{
+ struct ap_queue *queue;
struct vfio_ap_queue *q;
- struct device *dev;
- if (!test_bit_inv(AP_QID_CARD(apqn), matrix_mdev->matrix.apm))
- return NULL;
- if (!test_bit_inv(AP_QID_QUEUE(apqn), matrix_mdev->matrix.aqm))
+ queue = ap_get_qdev(apqn);
+ if (!queue)
return NULL;
- dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL,
- &apqn, match_apqn);
- if (!dev)
- return NULL;
- q = dev_get_drvdata(dev);
- q->matrix_mdev = matrix_mdev;
- put_device(dev);
+ q = dev_get_drvdata(&queue->ap_dev.device);
+ put_device(&queue->ap_dev.device);
return q;
}
@@ -293,10 +276,11 @@ static int handle_pqap(struct kvm_vcpu *vcpu)
matrix_mdev = container_of(vcpu->kvm->arch.crypto.pqap_hook,
struct ap_matrix_mdev, pqap_hook);
- q = vfio_ap_get_queue(matrix_mdev, apqn);
+ q = vfio_ap_get_queue(apqn);
if (!q)
goto out_unlock;
+ q->matrix_mdev = matrix_mdev;
status = vcpu->run->s.regs.gprs[1];
/* If IR bit(16) is set we enable the interrupt */
@@ -1116,16 +1100,11 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb,
static void vfio_ap_irq_disable_apqn(int apqn)
{
- struct device *dev;
struct vfio_ap_queue *q;
- dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL,
- &apqn, match_apqn);
- if (dev) {
- q = dev_get_drvdata(dev);
+ q = vfio_ap_get_queue(apqn);
+ if (q)
vfio_ap_irq_disable(q);
- put_device(dev);
- }
}
int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
@@ -1302,3 +1281,36 @@ void vfio_ap_mdev_unregister(void)
{
mdev_unregister_device(&matrix_dev->device);
}
+
+int vfio_ap_mdev_probe_queue(struct ap_queue *queue)
+{
+ struct vfio_ap_queue *q;
+
+ q = kzalloc(sizeof(*q), GFP_KERNEL);
+ if (!q)
+ return -ENOMEM;
+
+ mutex_lock(&matrix_dev->lock);
+ dev_set_drvdata(&queue->ap_dev.device, q);
+ q->apqn = queue->qid;
+ q->saved_isc = VFIO_AP_ISC_INVALID;
+ mutex_unlock(&matrix_dev->lock);
+
+ return 0;
+}
+
+void vfio_ap_mdev_remove_queue(struct ap_queue *queue)
+{
+ struct vfio_ap_queue *q;
+ int apid, apqi;
+
+ mutex_lock(&matrix_dev->lock);
+ q = dev_get_drvdata(&queue->ap_dev.device);
+ dev_set_drvdata(&queue->ap_dev.device, NULL);
+ apid = AP_QID_CARD(q->apqn);
+ apqi = AP_QID_QUEUE(q->apqn);
+ vfio_ap_mdev_reset_queue(apid, apqi, 1);
+ vfio_ap_irq_disable(q);
+ kfree(q);
+ mutex_unlock(&matrix_dev->lock);
+}
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
index f46dde56b464..a2aa05bec718 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -18,6 +18,7 @@
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/kvm_host.h>
+#include <linux/hashtable.h>
#include "ap_bus.h"
@@ -90,8 +91,6 @@ struct ap_matrix_mdev {
extern int vfio_ap_mdev_register(void);
extern void vfio_ap_mdev_unregister(void);
-int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
- unsigned int retry);
struct vfio_ap_queue {
struct ap_matrix_mdev *matrix_mdev;
@@ -100,5 +99,8 @@ struct vfio_ap_queue {
#define VFIO_AP_ISC_INVALID 0xff
unsigned char saved_isc;
};
-struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q);
+
+int vfio_ap_mdev_probe_queue(struct ap_queue *queue);
+void vfio_ap_mdev_remove_queue(struct ap_queue *queue);
+
#endif /* _VFIO_AP_PRIVATE_H_ */
--
2.21.1
Hi Tony,
I love your patch! Perhaps something to improve:
[auto build test WARNING on kvms390/next]
[also build test WARNING on linus/master v5.7]
[cannot apply to s390/features linux/master next-20200605]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Tony-Krowiak/s390-vfio-ap-dynamic-configuration-support/20200606-054350
base: https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git next
config: s390-allyesconfig (attached as .config)
compiler: s390-linux-gcc (GCC) 9.3.0
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
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=s390
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>, old ones prefixed by <<):
>> drivers/s390/crypto/vfio_ap_ops.c:130:24: warning: no previous prototype for 'vfio_ap_irq_disable' [-Wmissing-prototypes]
130 | struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q)
| ^~~~~~~~~~~~~~~~~~~
>> drivers/s390/crypto/vfio_ap_ops.c:1110:5: warning: no previous prototype for 'vfio_ap_mdev_reset_queue' [-Wmissing-prototypes]
1110 | int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
| ^~~~~~~~~~~~~~~~~~~~~~~~
vim +/vfio_ap_irq_disable +130 drivers/s390/crypto/vfio_ap_ops.c
ec89b55e3bce7c Pierre Morel 2019-05-21 113
ec89b55e3bce7c Pierre Morel 2019-05-21 114 /**
ec89b55e3bce7c Pierre Morel 2019-05-21 115 * vfio_ap_irq_disable
ec89b55e3bce7c Pierre Morel 2019-05-21 116 * @q: The vfio_ap_queue
ec89b55e3bce7c Pierre Morel 2019-05-21 117 *
ec89b55e3bce7c Pierre Morel 2019-05-21 118 * Uses ap_aqic to disable the interruption and in case of success, reset
ec89b55e3bce7c Pierre Morel 2019-05-21 119 * in progress or IRQ disable command already proceeded: calls
ec89b55e3bce7c Pierre Morel 2019-05-21 120 * vfio_ap_wait_for_irqclear() to check for the IRQ bit to be clear
ec89b55e3bce7c Pierre Morel 2019-05-21 121 * and calls vfio_ap_free_aqic_resources() to free the resources associated
ec89b55e3bce7c Pierre Morel 2019-05-21 122 * with the AP interrupt handling.
ec89b55e3bce7c Pierre Morel 2019-05-21 123 *
ec89b55e3bce7c Pierre Morel 2019-05-21 124 * In the case the AP is busy, or a reset is in progress,
ec89b55e3bce7c Pierre Morel 2019-05-21 125 * retries after 20ms, up to 5 times.
ec89b55e3bce7c Pierre Morel 2019-05-21 126 *
ec89b55e3bce7c Pierre Morel 2019-05-21 127 * Returns if ap_aqic function failed with invalid, deconfigured or
ec89b55e3bce7c Pierre Morel 2019-05-21 128 * checkstopped AP.
ec89b55e3bce7c Pierre Morel 2019-05-21 129 */
ec89b55e3bce7c Pierre Morel 2019-05-21 @130 struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q)
ec89b55e3bce7c Pierre Morel 2019-05-21 131 {
ec89b55e3bce7c Pierre Morel 2019-05-21 132 struct ap_qirq_ctrl aqic_gisa = {};
ec89b55e3bce7c Pierre Morel 2019-05-21 133 struct ap_queue_status status;
ec89b55e3bce7c Pierre Morel 2019-05-21 134 int retries = 5;
ec89b55e3bce7c Pierre Morel 2019-05-21 135
ec89b55e3bce7c Pierre Morel 2019-05-21 136 do {
ec89b55e3bce7c Pierre Morel 2019-05-21 137 status = ap_aqic(q->apqn, aqic_gisa, NULL);
ec89b55e3bce7c Pierre Morel 2019-05-21 138 switch (status.response_code) {
ec89b55e3bce7c Pierre Morel 2019-05-21 139 case AP_RESPONSE_OTHERWISE_CHANGED:
ec89b55e3bce7c Pierre Morel 2019-05-21 140 case AP_RESPONSE_NORMAL:
ec89b55e3bce7c Pierre Morel 2019-05-21 141 vfio_ap_wait_for_irqclear(q->apqn);
ec89b55e3bce7c Pierre Morel 2019-05-21 142 goto end_free;
ec89b55e3bce7c Pierre Morel 2019-05-21 143 case AP_RESPONSE_RESET_IN_PROGRESS:
ec89b55e3bce7c Pierre Morel 2019-05-21 144 case AP_RESPONSE_BUSY:
ec89b55e3bce7c Pierre Morel 2019-05-21 145 msleep(20);
ec89b55e3bce7c Pierre Morel 2019-05-21 146 break;
ec89b55e3bce7c Pierre Morel 2019-05-21 147 case AP_RESPONSE_Q_NOT_AVAIL:
ec89b55e3bce7c Pierre Morel 2019-05-21 148 case AP_RESPONSE_DECONFIGURED:
ec89b55e3bce7c Pierre Morel 2019-05-21 149 case AP_RESPONSE_CHECKSTOPPED:
ec89b55e3bce7c Pierre Morel 2019-05-21 150 case AP_RESPONSE_INVALID_ADDRESS:
ec89b55e3bce7c Pierre Morel 2019-05-21 151 default:
ec89b55e3bce7c Pierre Morel 2019-05-21 152 /* All cases in default means AP not operational */
ec89b55e3bce7c Pierre Morel 2019-05-21 153 WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
ec89b55e3bce7c Pierre Morel 2019-05-21 154 status.response_code);
ec89b55e3bce7c Pierre Morel 2019-05-21 155 goto end_free;
ec89b55e3bce7c Pierre Morel 2019-05-21 156 }
ec89b55e3bce7c Pierre Morel 2019-05-21 157 } while (retries--);
ec89b55e3bce7c Pierre Morel 2019-05-21 158
ec89b55e3bce7c Pierre Morel 2019-05-21 159 WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
ec89b55e3bce7c Pierre Morel 2019-05-21 160 status.response_code);
ec89b55e3bce7c Pierre Morel 2019-05-21 161 end_free:
ec89b55e3bce7c Pierre Morel 2019-05-21 162 vfio_ap_free_aqic_resources(q);
5c4c2126fb6981 Christian Borntraeger 2019-07-05 163 q->matrix_mdev = NULL;
ec89b55e3bce7c Pierre Morel 2019-05-21 164 return status;
ec89b55e3bce7c Pierre Morel 2019-05-21 165 }
ec89b55e3bce7c Pierre Morel 2019-05-21 166
:::::: The code at line 130 was first introduced by commit
:::::: ec89b55e3bce7c8a4bc6b1203280e81342d6745c s390: ap: implement PAPQ AQIC interception in kernel
:::::: TO: Pierre Morel <[email protected]>
:::::: CC: Vasily Gorbik <[email protected]>
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
On 05.06.20 23:39, Tony Krowiak wrote:
> This patch refactor's the vfio_ap device driver to use the AP bus's
> ap_get_qdev() function to retrieve the vfio_ap_queue struct containing
> information about a queue that is bound to the vfio_ap device driver.
> The bus's ap_get_qdev() function retrieves the queue device from a
> hashtable keyed by APQN. This is much more efficient than looping over
> the list of devices attached to the AP bus by several orders of
> magnitude.
>
> Signed-off-by: Tony Krowiak <[email protected]>
> ---
> drivers/s390/crypto/vfio_ap_drv.c | 27 ++-------
> drivers/s390/crypto/vfio_ap_ops.c | 82 +++++++++++++++------------
> drivers/s390/crypto/vfio_ap_private.h | 8 ++-
> 3 files changed, 58 insertions(+), 59 deletions(-)
>
> diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
> index be2520cc010b..59233cf7419d 100644
> --- a/drivers/s390/crypto/vfio_ap_drv.c
> +++ b/drivers/s390/crypto/vfio_ap_drv.c
> @@ -51,15 +51,9 @@ MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids);
> */
> static int vfio_ap_queue_dev_probe(struct ap_device *apdev)
> {
> - struct vfio_ap_queue *q;
> -
> - q = kzalloc(sizeof(*q), GFP_KERNEL);
> - if (!q)
> - return -ENOMEM;
> - dev_set_drvdata(&apdev->device, q);
> - q->apqn = to_ap_queue(&apdev->device)->qid;
> - q->saved_isc = VFIO_AP_ISC_INVALID;
> - return 0;
> + struct ap_queue *queue = to_ap_queue(&apdev->device);
> +
> + return vfio_ap_mdev_probe_queue(queue);
> }
Here we did not hold a mutex in the old code
[...]
> +int vfio_ap_mdev_probe_queue(struct ap_queue *queue)
> +{
> + struct vfio_ap_queue *q;
> +
> + q = kzalloc(sizeof(*q), GFP_KERNEL);
> + if (!q)
> + return -ENOMEM;
> +
> + mutex_lock(&matrix_dev->lock);
> + dev_set_drvdata(&queue->ap_dev.device, q);
> + q->apqn = queue->qid;
> + q->saved_isc = VFIO_AP_ISC_INVALID;
> + mutex_unlock(&matrix_dev->lock);
> +
here we do. Why do we need the matrix_dev->lock here?
On 05.06.20 23:39, Tony Krowiak wrote:
[..]
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -18,6 +18,7 @@
> #include <linux/delay.h>
> #include <linux/mutex.h>
> #include <linux/kvm_host.h>
> +#include <linux/hashtable.h>
>
> #include "ap_bus.h"
>
> @@ -90,8 +91,6 @@ struct ap_matrix_mdev {
>
> extern int vfio_ap_mdev_register(void);
> extern void vfio_ap_mdev_unregister(void);
> -int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
> - unsigned int retry);
>
> struct vfio_ap_queue {
> struct ap_matrix_mdev *matrix_mdev;
> @@ -100,5 +99,8 @@ struct vfio_ap_queue {
> #define VFIO_AP_ISC_INVALID 0xff
> unsigned char saved_isc;
> };
> -struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q);
This looks wrong and unrelated.
> +
> +int vfio_ap_mdev_probe_queue(struct ap_queue *queue);
> +void vfio_ap_mdev_remove_queue(struct ap_queue *queue);
> +
> #endif /* _VFIO_AP_PRIVATE_H_ */
>
On 6/16/20 11:45 AM, Christian Borntraeger wrote:
>
> On 05.06.20 23:39, Tony Krowiak wrote:
>> This patch refactor's the vfio_ap device driver to use the AP bus's
>> ap_get_qdev() function to retrieve the vfio_ap_queue struct containing
>> information about a queue that is bound to the vfio_ap device driver.
>> The bus's ap_get_qdev() function retrieves the queue device from a
>> hashtable keyed by APQN. This is much more efficient than looping over
>> the list of devices attached to the AP bus by several orders of
>> magnitude.
>>
>> Signed-off-by: Tony Krowiak <[email protected]>
>> ---
>> drivers/s390/crypto/vfio_ap_drv.c | 27 ++-------
>> drivers/s390/crypto/vfio_ap_ops.c | 82 +++++++++++++++------------
>> drivers/s390/crypto/vfio_ap_private.h | 8 ++-
>> 3 files changed, 58 insertions(+), 59 deletions(-)
>>
>> diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
>> index be2520cc010b..59233cf7419d 100644
>> --- a/drivers/s390/crypto/vfio_ap_drv.c
>> +++ b/drivers/s390/crypto/vfio_ap_drv.c
>> @@ -51,15 +51,9 @@ MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids);
>> */
>> static int vfio_ap_queue_dev_probe(struct ap_device *apdev)
>> {
>> - struct vfio_ap_queue *q;
>> -
>> - q = kzalloc(sizeof(*q), GFP_KERNEL);
>> - if (!q)
>> - return -ENOMEM;
>> - dev_set_drvdata(&apdev->device, q);
>> - q->apqn = to_ap_queue(&apdev->device)->qid;
>> - q->saved_isc = VFIO_AP_ISC_INVALID;
>> - return 0;
>> + struct ap_queue *queue = to_ap_queue(&apdev->device);
>> +
>> + return vfio_ap_mdev_probe_queue(queue);
>> }
> Here we did not hold a mutex in the old code
> [...]
>
>> +int vfio_ap_mdev_probe_queue(struct ap_queue *queue)
>> +{
>> + struct vfio_ap_queue *q;
>> +
>> + q = kzalloc(sizeof(*q), GFP_KERNEL);
>> + if (!q)
>> + return -ENOMEM;
>> +
>> + mutex_lock(&matrix_dev->lock);
>> + dev_set_drvdata(&queue->ap_dev.device, q);
>> + q->apqn = queue->qid;
>> + q->saved_isc = VFIO_AP_ISC_INVALID;
>> + mutex_unlock(&matrix_dev->lock);
>> +
> here we do. Why do we need the matrix_dev->lock here?
You are correct, we don't need it here; but, we will need it
in a subsequent patch where we introduce linking the
q to the matrix mdev to which it is assigned. Perhaps
the locking should be introduced in that patch.
>