From: Mika Penttilä <[email protected]>
HMM selftests use an in-kernel pseudo device to emulate device private
memory. The pseudo device registers a major device range for two pseudo
device instances. User space has a script that reads /proc/devices in
order to find the assigned major number, and sends that to mknod(1),
once for each node.
Change this to properly use cdev and struct device APIs.
Delete the /proc/devices parsing from the user-space test script, now
that it is unnecessary.
Also, deleted an unused field in struct dmirror_device: devmem.
Signed-off-by: Mika Penttilä <[email protected]>
Reviewed-by: John Hubbard <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Vlastimil Babka <[email protected]>
---
v5:
- fix whitespace
. delete unused structure field
v4:
- fix commit log
v3:
- use cdev_device_add() instead of miscdevice
v2:
- Cleanups per review comments from John Hubbard
- Added Tested-by and Ccs
lib/test_hmm.c | 18 ++++++++++++++----
tools/testing/selftests/vm/test_hmm.sh | 6 ------
2 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/lib/test_hmm.c b/lib/test_hmm.c
index 767538089a62..3c7f2a92b09e 100644
--- a/lib/test_hmm.c
+++ b/lib/test_hmm.c
@@ -29,11 +29,17 @@
#include "test_hmm_uapi.h"
-#define DMIRROR_NDEVICES 2
#define DMIRROR_RANGE_FAULT_TIMEOUT 1000
#define DEVMEM_CHUNK_SIZE (256 * 1024 * 1024U)
#define DEVMEM_CHUNKS_RESERVE 16
+static const char *dmirror_device_names[] = {
+ "hmm_dmirror0",
+ "hmm_dmirror1"
+};
+
+#define DMIRROR_NDEVICES ARRAY_SIZE(dmirror_device_names)
+
static const struct dev_pagemap_ops dmirror_devmem_ops;
static const struct mmu_interval_notifier_ops dmirror_min_ops;
static dev_t dmirror_dev;
@@ -83,7 +89,7 @@ struct dmirror_chunk {
*/
struct dmirror_device {
struct cdev cdevice;
- struct hmm_devmem *devmem;
+ struct device device;
unsigned int devmem_capacity;
unsigned int devmem_count;
@@ -1225,7 +1231,11 @@ static int dmirror_device_init(struct dmirror_device *mdevice, int id)
cdev_init(&mdevice->cdevice, &dmirror_fops);
mdevice->cdevice.owner = THIS_MODULE;
- ret = cdev_add(&mdevice->cdevice, dev, 1);
+ device_initialize(&mdevice->device);
+ dev_set_name(&mdevice->device, "%s", dmirror_device_names[id]);
+ mdevice->device.devt = dev;
+
+ ret = cdev_device_add(&mdevice->cdevice, &mdevice->device);
if (ret)
return ret;
@@ -1252,7 +1262,7 @@ static void dmirror_device_remove(struct dmirror_device *mdevice)
kfree(mdevice->devmem_chunks);
}
- cdev_del(&mdevice->cdevice);
+ cdev_device_del(&mdevice->cdevice, &mdevice->device);
}
static int __init hmm_dmirror_init(void)
diff --git a/tools/testing/selftests/vm/test_hmm.sh b/tools/testing/selftests/vm/test_hmm.sh
index 0647b525a625..69f5889f8575 100755
--- a/tools/testing/selftests/vm/test_hmm.sh
+++ b/tools/testing/selftests/vm/test_hmm.sh
@@ -41,17 +41,11 @@ check_test_requirements()
load_driver()
{
modprobe $DRIVER > /dev/null 2>&1
- if [ $? == 0 ]; then
- major=$(awk "\$2==\"HMM_DMIRROR\" {print \$1}" /proc/devices)
- mknod /dev/hmm_dmirror0 c $major 0
- mknod /dev/hmm_dmirror1 c $major 1
- fi
}
unload_driver()
{
modprobe -r $DRIVER > /dev/null 2>&1
- rm -f /dev/hmm_dmirror?
}
run_smoke()
--
2.17.1
On Tue, Mar 22, 2022 at 06:35:43AM +0200, [email protected] wrote:
> From: Mika Penttilä <[email protected]>
>
> HMM selftests use an in-kernel pseudo device to emulate device private
> memory. The pseudo device registers a major device range for two pseudo
> device instances. User space has a script that reads /proc/devices in
> order to find the assigned major number, and sends that to mknod(1),
> once for each node.
>
> Change this to properly use cdev and struct device APIs.
>
> Delete the /proc/devices parsing from the user-space test script, now
> that it is unnecessary.
>
> Also, deleted an unused field in struct dmirror_device: devmem.
>
> Signed-off-by: Mika Penttilä <[email protected]>
> Reviewed-by: John Hubbard <[email protected]>
> Cc: Alistair Popple <[email protected]>
> Cc: Ralph Campbell <[email protected]>
> Cc: Jason Gunthorpe <[email protected]>
> Cc: Vlastimil Babka <[email protected]>
> v5:
> - fix whitespace
> . delete unused structure field
> v4:
> - fix commit log
> v3:
> - use cdev_device_add() instead of miscdevice
> v2:
> - Cleanups per review comments from John Hubbard
> - Added Tested-by and Ccs
>
> lib/test_hmm.c | 18 ++++++++++++++----
> tools/testing/selftests/vm/test_hmm.sh | 6 ------
> 2 files changed, 14 insertions(+), 10 deletions(-)
>
> diff --git a/lib/test_hmm.c b/lib/test_hmm.c
> index 767538089a62..3c7f2a92b09e 100644
> +++ b/lib/test_hmm.c
> @@ -29,11 +29,17 @@
>
> #include "test_hmm_uapi.h"
>
> -#define DMIRROR_NDEVICES 2
> #define DMIRROR_RANGE_FAULT_TIMEOUT 1000
> #define DEVMEM_CHUNK_SIZE (256 * 1024 * 1024U)
> #define DEVMEM_CHUNKS_RESERVE 16
>
> +static const char *dmirror_device_names[] = {
> + "hmm_dmirror0",
> + "hmm_dmirror1"
> +};
> +
> +#define DMIRROR_NDEVICES ARRAY_SIZE(dmirror_device_names)
> +
> static const struct dev_pagemap_ops dmirror_devmem_ops;
> static const struct mmu_interval_notifier_ops dmirror_min_ops;
> static dev_t dmirror_dev;
> @@ -83,7 +89,7 @@ struct dmirror_chunk {
> */
> struct dmirror_device {
> struct cdev cdevice;
> - struct hmm_devmem *devmem;
> + struct device device;
>
> unsigned int devmem_capacity;
> unsigned int devmem_count;
> @@ -1225,7 +1231,11 @@ static int dmirror_device_init(struct dmirror_device *mdevice, int id)
>
> cdev_init(&mdevice->cdevice, &dmirror_fops);
> mdevice->cdevice.owner = THIS_MODULE;
> - ret = cdev_add(&mdevice->cdevice, dev, 1);
> + device_initialize(&mdevice->device);
> + dev_set_name(&mdevice->device, "%s", dmirror_device_names[id]);
Just
dev_set_name(&mdevice->device, "hmm_dmirror%u", id);
No need for an array
Also check for error
Jason
On 25.3.2022 20.17, Jason Gunthorpe wrote:
> On Tue, Mar 22, 2022 at 06:35:43AM +0200, [email protected] wrote:
>> From: Mika Penttilä <[email protected]>
>>
>> HMM selftests use an in-kernel pseudo device to emulate device private
>> memory. The pseudo device registers a major device range for two pseudo
>> device instances. User space has a script that reads /proc/devices in
>> order to find the assigned major number, and sends that to mknod(1),
>> once for each node.
>>
>> Change this to properly use cdev and struct device APIs.
>>
>> Delete the /proc/devices parsing from the user-space test script, now
>> that it is unnecessary.
>>
>> Also, deleted an unused field in struct dmirror_device: devmem.
>>
>> Signed-off-by: Mika Penttilä <[email protected]>
>> Reviewed-by: John Hubbard <[email protected]>
>> Cc: Alistair Popple <[email protected]>
>> Cc: Ralph Campbell <[email protected]>
>> Cc: Jason Gunthorpe <[email protected]>
>> Cc: Vlastimil Babka <[email protected]>
>> v5:
>> - fix whitespace
>> . delete unused structure field
>> v4:
>> - fix commit log
>> v3:
>> - use cdev_device_add() instead of miscdevice
>> v2:
>> - Cleanups per review comments from John Hubbard
>> - Added Tested-by and Ccs
>>
>> lib/test_hmm.c | 18 ++++++++++++++----
>> tools/testing/selftests/vm/test_hmm.sh | 6 ------
>> 2 files changed, 14 insertions(+), 10 deletions(-)
>>
>> diff --git a/lib/test_hmm.c b/lib/test_hmm.c
>> index 767538089a62..3c7f2a92b09e 100644
>> +++ b/lib/test_hmm.c
>> @@ -29,11 +29,17 @@
>>
>> #include "test_hmm_uapi.h"
>>
>> -#define DMIRROR_NDEVICES 2
>> #define DMIRROR_RANGE_FAULT_TIMEOUT 1000
>> #define DEVMEM_CHUNK_SIZE (256 * 1024 * 1024U)
>> #define DEVMEM_CHUNKS_RESERVE 16
>>
>> +static const char *dmirror_device_names[] = {
>> + "hmm_dmirror0",
>> + "hmm_dmirror1"
>> +};
>> +
>> +#define DMIRROR_NDEVICES ARRAY_SIZE(dmirror_device_names)
>> +
>> static const struct dev_pagemap_ops dmirror_devmem_ops;
>> static const struct mmu_interval_notifier_ops dmirror_min_ops;
>> static dev_t dmirror_dev;
>> @@ -83,7 +89,7 @@ struct dmirror_chunk {
>> */
>> struct dmirror_device {
>> struct cdev cdevice;
>> - struct hmm_devmem *devmem;
>> + struct device device;
>>
>> unsigned int devmem_capacity;
>> unsigned int devmem_count;
>> @@ -1225,7 +1231,11 @@ static int dmirror_device_init(struct dmirror_device *mdevice, int id)
>>
>> cdev_init(&mdevice->cdevice, &dmirror_fops);
>> mdevice->cdevice.owner = THIS_MODULE;
>> - ret = cdev_add(&mdevice->cdevice, dev, 1);
>> + device_initialize(&mdevice->device);
>> + dev_set_name(&mdevice->device, "%s", dmirror_device_names[id]);
>
> Just
> dev_set_name(&mdevice->device, "hmm_dmirror%u", id);
>
> No need for an array
Yeah, no absolute need, thought names in an array is less hardcoded wrt
device node count and naming standard.
>
> Also check for error
True. Interesting fact is that even the device core itself doesn't check
for errors calling dev_set_name(), but sure it can fail in memory
allocations.
>
> Jason
>
Mika