| Message ID | 20190613094326.24093-4-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/22] mm: remove the unused ARCH_HAS_HMM_DEVICE Kconfig option | expand |
On Thu, Jun 13, 2019 at 11:43:06AM +0200, 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. nit: Have we simplified the interface for devm_memremap_pages() at this point, or are you talking about later patches in this series. I checked this and all the called functions are exported symbols, so there is no blocker for a future driver to call devm_memremap_pages(), maybe even with all this boiler plate, in future. If we eventually get many users that need some simplified registration then we should add a devm_memremap_pages_simplified() interface and factor out that code when we can see the pattern. Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Jason
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,
On Thu, Jun 13, 2019 at 06:52:44PM +0000, Jason Gunthorpe wrote: > On Thu, Jun 13, 2019 at 11:43:06AM +0200, 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. > > nit: Have we simplified the interface for devm_memremap_pages() at > this point, or are you talking about later patches in this series. After this series. I've just droped that part of the sentence to avoid confusion. > I checked this and all the called functions are exported symbols, so > there is no blocker for a future driver to call devm_memremap_pages(), > maybe even with all this boiler plate, in future. > > If we eventually get many users that need some simplified registration > then we should add a devm_memremap_pages_simplified() interface and > factor out that code when we can see the pattern. After this series devm_memremap_pages already is simpler to use than hmm_device_add_resource was before, so I'm not worried at all. The series actually net removes lines from noveau (if only a few).
On Thu 13-06-19 11:43:06, 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> Acked-by: Michal Hocko <mhocko@suse.com> > --- > include/linux/hmm.h | 3 --- > mm/hmm.c | 54 --------------------------------------------- > 2 files changed, 57 deletions(-) > > 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 */ > -- > 2.20.1
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 */
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(-)