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mm: move get_dev_pagemap out of line

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This is a pretty big function, which should be out of line in general,
and a no-op stub if CONFIG_ZONE_DEVICЕ is not set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Christoph Hellwig 2017-12-29 08:54:00 +01:00 committed by Dan Williams
parent eb8045335c
commit 0822acb86c
2 changed files with 38 additions and 37 deletions
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39
include/linux/memremap.h
View File

@ -133,7 +133,8 @@ struct dev_pagemap {
#ifdef CONFIG_ZONE_DEVICE
void *devm_memremap_pages(struct device *dev, struct resource *res,
struct percpu_ref *ref, struct vmem_altmap *altmap);
struct dev_pagemap *find_dev_pagemap(resource_size_t phys);
struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
struct dev_pagemap *pgmap);
unsigned long vmem_altmap_offset(struct vmem_altmap *altmap);
void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns);
@ -153,7 +154,8 @@ static inline void *devm_memremap_pages(struct device *dev,
return ERR_PTR(-ENXIO);
}
static inline struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
static inline struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
struct dev_pagemap *pgmap)
{
return NULL;
}
@ -183,39 +185,6 @@ static inline bool is_device_public_page(const struct page *page)
}
#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
/**
* get_dev_pagemap() - take a new live reference on the dev_pagemap for @pfn
* @pfn: page frame number to lookup page_map
* @pgmap: optional known pgmap that already has a reference
*
* @pgmap allows the overhead of a lookup to be bypassed when @pfn lands in the
* same mapping.
*/
static inline struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
struct dev_pagemap *pgmap)
{
const struct resource *res = pgmap ? pgmap->res : NULL;
resource_size_t phys = PFN_PHYS(pfn);
/*
* In the cached case we're already holding a live reference so
* we can simply do a blind increment
*/
if (res && phys >= res->start && phys <= res->end) {
percpu_ref_get(pgmap->ref);
return pgmap;
}
/* fall back to slow path lookup */
rcu_read_lock();
pgmap = find_dev_pagemap(phys);
if (pgmap && !percpu_ref_tryget_live(pgmap->ref))
pgmap = NULL;
rcu_read_unlock();
return pgmap;
}
static inline void put_dev_pagemap(struct dev_pagemap *pgmap)
{
if (pgmap)

36
kernel/memremap.c
View File

@ -314,7 +314,7 @@ static void devm_memremap_pages_release(struct device *dev, void *data)
}
/* assumes rcu_read_lock() held at entry */
struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
static struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
{
struct page_map *page_map;
@ -501,8 +501,40 @@ struct vmem_altmap *to_vmem_altmap(unsigned long memmap_start)
return pgmap ? pgmap->altmap : NULL;
}
#endif /* CONFIG_ZONE_DEVICE */
/**
* get_dev_pagemap() - take a new live reference on the dev_pagemap for @pfn
* @pfn: page frame number to lookup page_map
* @pgmap: optional known pgmap that already has a reference
*
* @pgmap allows the overhead of a lookup to be bypassed when @pfn lands in the
* same mapping.
*/
struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
struct dev_pagemap *pgmap)
{
const struct resource *res = pgmap ? pgmap->res : NULL;
resource_size_t phys = PFN_PHYS(pfn);
/*
* In the cached case we're already holding a live reference so
* we can simply do a blind increment
*/
if (res && phys >= res->start && phys <= res->end) {
percpu_ref_get(pgmap->ref);
return pgmap;
}
/* fall back to slow path lookup */
rcu_read_lock();
pgmap = find_dev_pagemap(phys);
if (pgmap && !percpu_ref_tryget_live(pgmap->ref))
pgmap = NULL;
rcu_read_unlock();
return pgmap;
}
#endif /* CONFIG_ZONE_DEVICE */
#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC)
void put_zone_device_private_or_public_page(struct page *page)