On Tue, Mar 22, 2022 at 06:35:43AM +0200, mpenttil@xxxxxxxxxx wrote:
> From: Mika Penttilä <mpenttil@xxxxxxxxxx>
>
> 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@xxxxxxxxxx>
> Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>
> Cc: Alistair Popple <apopple@xxxxxxxxxx>
> Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
> Cc: Jason Gunthorpe <jgg@xxxxxxxx>
> Cc: Vlastimil Babka <vbabka@xxxxxxx>
> 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
