| Message ID | 20220322043543.18424-1-mpenttil@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v5] mm/hmm/test: use char dev with struct device to get device node | expand |
On Tue, Mar 22, 2022 at 06:35:43AM +0200, mpenttil@redhat.com wrote: > From: Mika Penttilä <mpenttil@redhat.com> > > 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 <mpenttil@redhat.com> > Reviewed-by: John Hubbard <jhubbard@nvidia.com> > Cc: Alistair Popple <apopple@nvidia.com> > Cc: Ralph Campbell <rcampbell@nvidia.com> > Cc: Jason Gunthorpe <jgg@ziepe.ca> > Cc: Vlastimil Babka <vbabka@suse.cz> > 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, mpenttil@redhat.com wrote: >> From: Mika Penttilä <mpenttil@redhat.com> >> >> 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 <mpenttil@redhat.com> >> Reviewed-by: John Hubbard <jhubbard@nvidia.com> >> Cc: Alistair Popple <apopple@nvidia.com> >> Cc: Ralph Campbell <rcampbell@nvidia.com> >> Cc: Jason Gunthorpe <jgg@ziepe.ca> >> Cc: Vlastimil Babka <vbabka@suse.cz> >> 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
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()