memremap: drop private struct page_map

'struct page_map' is a private structure of 'struct dev_pagemap' but the
latter replicates all the same fields as the former so there isn't much
value in it. Thus drop it in favour of a completely public struct.

This is a clean up in preperation for a more generally useful
'devm_memeremap_pages' interface.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index 3fddcfe57bb004d2fa8b10182d2011dee20fd342..1cb5f39d25c15b918fbd51c6c88eba44237b52c0 100644 (file)
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -113,8 +113,9 @@ typedef void (*dev_page_free_t)(struct page *page, void *data);
 struct dev_pagemap {
        dev_page_fault_t page_fault;
        dev_page_free_t page_free;
-       struct vmem_altmap *altmap;
-       const struct resource *res;
+       struct vmem_altmap altmap;
+       bool altmap_valid;
+       struct resource res;
        struct percpu_ref *ref;
        struct device *dev;
        void *data;

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 12e78528fea4c78d0b969c242068f53d7e211719..9207c44cce201efd5dbd127758fac70d08870e46 100644 (file)
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -188,13 +188,6 @@ static RADIX_TREE(pgmap_radix, GFP_KERNEL);
 #define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
 #define SECTION_SIZE (1UL << PA_SECTION_SHIFT)
 
-struct page_map {
-       struct resource res;
-       struct percpu_ref *ref;
-       struct dev_pagemap pgmap;
-       struct vmem_altmap altmap;
-};
-
 static unsigned long order_at(struct resource *res, unsigned long pgoff)
 {
        unsigned long phys_pgoff = PHYS_PFN(res->start) + pgoff;
@@ -260,22 +253,21 @@ static void pgmap_radix_release(struct resource *res)
        synchronize_rcu();
 }
 
-static unsigned long pfn_first(struct page_map *page_map)
+static unsigned long pfn_first(struct dev_pagemap *pgmap)
 {
-       struct dev_pagemap *pgmap = &page_map->pgmap;
-       const struct resource *res = &page_map->res;
-       struct vmem_altmap *altmap = pgmap->altmap;
+       const struct resource *res = &pgmap->res;
+       struct vmem_altmap *altmap = &pgmap->altmap;
        unsigned long pfn;
 
        pfn = res->start >> PAGE_SHIFT;
-       if (altmap)
+       if (pgmap->altmap_valid)
                pfn += vmem_altmap_offset(altmap);
        return pfn;
 }
 
-static unsigned long pfn_end(struct page_map *page_map)
+static unsigned long pfn_end(struct dev_pagemap *pgmap)
 {
-       const struct resource *res = &page_map->res;
+       const struct resource *res = &pgmap->res;
 
        return (res->start + resource_size(res)) >> PAGE_SHIFT;
 }
@@ -285,13 +277,12 @@ static unsigned long pfn_end(struct page_map *page_map)
 
 static void devm_memremap_pages_release(struct device *dev, void *data)
 {
-       struct page_map *page_map = data;
-       struct resource *res = &page_map->res;
+       struct dev_pagemap *pgmap = data;
+       struct resource *res = &pgmap->res;
        resource_size_t align_start, align_size;
-       struct dev_pagemap *pgmap = &page_map->pgmap;
        unsigned long pfn;
 
-       for_each_device_pfn(pfn, page_map)
+       for_each_device_pfn(pfn, pgmap)
                put_page(pfn_to_page(pfn));
 
        if (percpu_ref_tryget_live(pgmap->ref)) {
@@ -304,24 +295,22 @@ static void devm_memremap_pages_release(struct device *dev, void *data)
        align_size = ALIGN(resource_size(res), SECTION_SIZE);
 
        mem_hotplug_begin();
-       arch_remove_memory(align_start, align_size, pgmap->altmap);
+       arch_remove_memory(align_start, align_size, pgmap->altmap_valid ?
+                       &pgmap->altmap : NULL);
        mem_hotplug_done();
 
        untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
        pgmap_radix_release(res);
-       dev_WARN_ONCE(dev, pgmap->altmap && pgmap->altmap->alloc,
-                       "%s: failed to free all reserved pages\n", __func__);
+       dev_WARN_ONCE(dev, pgmap->altmap.alloc,
+                     "%s: failed to free all reserved pages\n", __func__);
 }
 
 /* assumes rcu_read_lock() held at entry */
 static struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
 {
-       struct page_map *page_map;
-
        WARN_ON_ONCE(!rcu_read_lock_held());
 
-       page_map = radix_tree_lookup(&pgmap_radix, PHYS_PFN(phys));
-       return page_map ? &page_map->pgmap : NULL;
+       return radix_tree_lookup(&pgmap_radix, PHYS_PFN(phys));
 }
 
 /**
@@ -349,7 +338,6 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
        unsigned long pfn, pgoff, order;
        pgprot_t pgprot = PAGE_KERNEL;
        struct dev_pagemap *pgmap;
-       struct page_map *page_map;
        int error, nid, is_ram, i = 0;
 
        align_start = res->start & ~(SECTION_SIZE - 1);
@@ -370,22 +358,20 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
        if (!ref)
                return ERR_PTR(-EINVAL);
 
-       page_map = devres_alloc_node(devm_memremap_pages_release,
-                       sizeof(*page_map), GFP_KERNEL, dev_to_node(dev));
-       if (!page_map)
+       pgmap = devres_alloc_node(devm_memremap_pages_release,
+                       sizeof(*pgmap), GFP_KERNEL, dev_to_node(dev));
+       if (!pgmap)
                return ERR_PTR(-ENOMEM);
-       pgmap = &page_map->pgmap;
 
-       memcpy(&page_map->res, res, sizeof(*res));
+       memcpy(&pgmap->res, res, sizeof(*res));
 
        pgmap->dev = dev;
        if (altmap) {
-               memcpy(&page_map->altmap, altmap, sizeof(*altmap));
-               pgmap->altmap = &page_map->altmap;
-               altmap = pgmap->altmap;
+               memcpy(&pgmap->altmap, altmap, sizeof(*altmap));
+               pgmap->altmap_valid = true;
+               altmap = &pgmap->altmap;
        }
        pgmap->ref = ref;
-       pgmap->res = &page_map->res;
        pgmap->type = MEMORY_DEVICE_HOST;
        pgmap->page_fault = NULL;
        pgmap->page_free = NULL;
@@ -397,7 +383,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 
        foreach_order_pgoff(res, order, pgoff) {
                error = __radix_tree_insert(&pgmap_radix,
-                               PHYS_PFN(res->start) + pgoff, order, page_map);
+                               PHYS_PFN(res->start) + pgoff, order, pgmap);
                if (error) {
                        dev_err(dev, "%s: failed: %d\n", __func__, error);
                        break;
@@ -426,7 +412,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
        if (error)
                goto err_add_memory;
 
-       for_each_device_pfn(pfn, page_map) {
+       for_each_device_pfn(pfn, pgmap) {
                struct page *page = pfn_to_page(pfn);
 
                /*
@@ -441,7 +427,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
                if (!(++i % 1024))
                        cond_resched();
        }
-       devres_add(dev, page_map);
+       devres_add(dev, pgmap);
        return __va(res->start);
 
  err_add_memory:
@@ -449,7 +435,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
  err_pfn_remap:
  err_radix:
        pgmap_radix_release(res);
-       devres_free(page_map);
+       devres_free(pgmap);
        return ERR_PTR(error);
 }
 EXPORT_SYMBOL(devm_memremap_pages);
@@ -482,9 +468,7 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
         * In the cached case we're already holding a live reference.
         */
        if (pgmap) {
-               const struct resource *res = pgmap ? pgmap->res : NULL;
-
-               if (res && phys >= res->start && phys <= res->end)
+               if (phys >= pgmap->res.start && phys <= pgmap->res.end)
                        return pgmap;
                put_dev_pagemap(pgmap);
        }

diff --git a/mm/hmm.c b/mm/hmm.c
index 2f2e13c61040ba38327129f92da715291bf16662..320fdc87f064364a4f8d2835cf430a1c3be58915 100644 (file)
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -882,7 +882,7 @@ static int hmm_devmem_pages_create(struct hmm_devmem *devmem)
        else
                devmem->pagemap.type = MEMORY_DEVICE_PRIVATE;
 
-       devmem->pagemap.res = devmem->resource;
+       devmem->pagemap.res = *devmem->resource;
        devmem->pagemap.page_fault = hmm_devmem_fault;
        devmem->pagemap.page_free = hmm_devmem_free;
        devmem->pagemap.dev = devmem->device;