Re: [Nouveau] [PATCH 03/22] mm: remove hmm_devmem_add_resource

John Hubbard
2019-06-14T00:54:08Z

On 6/13/19 2:43 AM, Christoph Hellwig wrote:
> This function has never been used since it was first added to the kernel
> more than a year and a half ago, and if we ever grow a consumer of the
> MEMORY_DEVICE_PUBLIC infrastructure it can easily use devm_memremap_pages
> directly now that we've simplified the API for it.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> include/linux/hmm.h | 3 ---
> mm/hmm.c | 54 ---------------------------------------------
> 2 files changed, 57 deletions(-)
>

No objections here, good cleanup.

Reviewed-by: John Hubbard <jhubbard@nvidia.com>

thanks,
--
John Hubbard
NVIDIA

> diff --git a/include/linux/hmm.h b/include/linux/hmm.h
> index 4867b9da1b6c..5761a39221a6 100644
> --- a/include/linux/hmm.h
> +++ b/include/linux/hmm.h
> @@ -688,9 +688,6 @@ struct hmm_devmem {
> struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops,
> struct device *device,
> unsigned long size);
> -struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops,
> - struct device *device,
> - struct resource *res);
>
> /*
> * hmm_devmem_page_set_drvdata - set per-page driver data field
> diff --git a/mm/hmm.c b/mm/hmm.c
> index ff2598eb7377..0c62426d1257 100644
> --- a/mm/hmm.c
> +++ b/mm/hmm.c
> @@ -1445,58 +1445,4 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops,
> return devmem;
> }
> EXPORT_SYMBOL_GPL(hmm_devmem_add);
> -
> -struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops,
> - struct device *device,
> - struct resource *res)
> -{
> - struct hmm_devmem *devmem;
> - void *result;
> - int ret;
> -
> - if (res->desc != IORES_DESC_DEVICE_PUBLIC_MEMORY)
> - return ERR_PTR(-EINVAL);
> -
> - dev_pagemap_get_ops();
> -
> - devmem = devm_kzalloc(device, sizeof(*devmem), GFP_KERNEL);
> - if (!devmem)
> - return ERR_PTR(-ENOMEM);
> -
> - init_completion(&devmem->completion);
> - devmem->pfn_first = -1UL;
> - devmem->pfn_last = -1UL;
> - devmem->resource = res;
> - devmem->device = device;
> - devmem->ops = ops;
> -
> - ret = percpu_ref_init(&devmem->ref, &hmm_devmem_ref_release,
> - 0, GFP_KERNEL);
> - if (ret)
> - return ERR_PTR(ret);
> -
> - ret = devm_add_action_or_reset(device, hmm_devmem_ref_exit,
> - &devmem->ref);
> - if (ret)
> - return ERR_PTR(ret);
> -
> - devmem->pfn_first = devmem->resource->start >> PAGE_SHIFT;
> - devmem->pfn_last = devmem->pfn_first +
> - (resource_size(devmem->resource) >> PAGE_SHIFT);
> - devmem->page_fault = hmm_devmem_fault;
> -
> - devmem->pagemap.type = MEMORY_DEVICE_PUBLIC;
> - devmem->pagemap.res = *devmem->resource;
> - devmem->pagemap.page_free = hmm_devmem_free;
> - devmem->pagemap.altmap_valid = false;
> - devmem->pagemap.ref = &devmem->ref;
> - devmem->pagemap.data = devmem;
> - devmem->pagemap.kill = hmm_devmem_ref_kill;
> -
> - result = devm_memremap_pages(devmem->device, &devmem->pagemap);
> - if (IS_ERR(result))
> - return result;
> - return devmem;
> -}
> -EXPORT_SYMBOL_GPL(hmm_devmem_add_resource);
> #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */