Contributors: 32
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Dan J Williams |
1090 |
49.37% |
31 |
31.00% |
| Christoph Hellwig |
514 |
23.28% |
23 |
23.00% |
| Matthew Wilcox |
95 |
4.30% |
4 |
4.00% |
| Alistair Popple |
79 |
3.58% |
2 |
2.00% |
| Ralph Campbell |
73 |
3.31% |
3 |
3.00% |
| Andrey Ryabinin |
42 |
1.90% |
1 |
1.00% |
| Logan Gunthorpe |
41 |
1.86% |
3 |
3.00% |
| David Hildenbrand |
34 |
1.54% |
3 |
3.00% |
| Anshuman Khandual |
33 |
1.49% |
1 |
1.00% |
| Alex Sierra |
32 |
1.45% |
1 |
1.00% |
| Jérôme Glisse |
29 |
1.31% |
4 |
4.00% |
| Joao Martins |
27 |
1.22% |
2 |
2.00% |
| Alexander Duyck |
22 |
1.00% |
1 |
1.00% |
| Michal Hocko |
18 |
0.82% |
1 |
1.00% |
| Aneesh Kumar K.V |
16 |
0.72% |
1 |
1.00% |
| Kamezawa Hiroyuki |
7 |
0.32% |
1 |
1.00% |
| Miaohe Lin |
7 |
0.32% |
3 |
3.00% |
| Nicholas Piggin |
7 |
0.32% |
1 |
1.00% |
| David Brownell |
6 |
0.27% |
1 |
1.00% |
| Song Muchun |
5 |
0.23% |
1 |
1.00% |
| Pankaj Gupta |
5 |
0.23% |
1 |
1.00% |
| Suren Baghdasaryan |
4 |
0.18% |
1 |
1.00% |
| Oscar Salvador |
4 |
0.18% |
1 |
1.00% |
| Dave Jiang |
4 |
0.18% |
1 |
1.00% |
| Sumanth Korikkar |
3 |
0.14% |
1 |
1.00% |
| Lee Schermerhorn |
3 |
0.14% |
1 |
1.00% |
| Steve French |
2 |
0.09% |
1 |
1.00% |
| Ira Weiny |
2 |
0.09% |
1 |
1.00% |
| Li Zhijian |
1 |
0.05% |
1 |
1.00% |
| Christophe Jaillet |
1 |
0.05% |
1 |
1.00% |
| Zhiyuan Dai |
1 |
0.05% |
1 |
1.00% |
| Andrew Morton |
1 |
0.05% |
1 |
1.00% |
| Total |
2208 |
|
100 |
|
// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2015 Intel Corporation. All rights reserved. */
#include <linux/device.h>
#include <linux/io.h>
#include <linux/kasan.h>
#include <linux/memory_hotplug.h>
#include <linux/memremap.h>
#include <linux/pfn_t.h>
#include <linux/swap.h>
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/swapops.h>
#include <linux/types.h>
#include <linux/wait_bit.h>
#include <linux/xarray.h>
#include "internal.h"
static DEFINE_XARRAY(pgmap_array);
/*
* The memremap() and memremap_pages() interfaces are alternately used
* to map persistent memory namespaces. These interfaces place different
* constraints on the alignment and size of the mapping (namespace).
* memremap() can map individual PAGE_SIZE pages. memremap_pages() can
* only map subsections (2MB), and at least one architecture (PowerPC)
* the minimum mapping granularity of memremap_pages() is 16MB.
*
* The role of memremap_compat_align() is to communicate the minimum
* arch supported alignment of a namespace such that it can freely
* switch modes without violating the arch constraint. Namely, do not
* allow a namespace to be PAGE_SIZE aligned since that namespace may be
* reconfigured into a mode that requires SUBSECTION_SIZE alignment.
*/
#ifndef CONFIG_ARCH_HAS_MEMREMAP_COMPAT_ALIGN
unsigned long memremap_compat_align(void)
{
return SUBSECTION_SIZE;
}
EXPORT_SYMBOL_GPL(memremap_compat_align);
#endif
#ifdef CONFIG_FS_DAX
DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
EXPORT_SYMBOL(devmap_managed_key);
static void devmap_managed_enable_put(struct dev_pagemap *pgmap)
{
if (pgmap->type == MEMORY_DEVICE_FS_DAX)
static_branch_dec(&devmap_managed_key);
}
static void devmap_managed_enable_get(struct dev_pagemap *pgmap)
{
if (pgmap->type == MEMORY_DEVICE_FS_DAX)
static_branch_inc(&devmap_managed_key);
}
#else
static void devmap_managed_enable_get(struct dev_pagemap *pgmap)
{
}
static void devmap_managed_enable_put(struct dev_pagemap *pgmap)
{
}
#endif /* CONFIG_FS_DAX */
static void pgmap_array_delete(struct range *range)
{
xa_store_range(&pgmap_array, PHYS_PFN(range->start), PHYS_PFN(range->end),
NULL, GFP_KERNEL);
synchronize_rcu();
}
static unsigned long pfn_first(struct dev_pagemap *pgmap, int range_id)
{
struct range *range = &pgmap->ranges[range_id];
unsigned long pfn = PHYS_PFN(range->start);
if (range_id)
return pfn;
return pfn + vmem_altmap_offset(pgmap_altmap(pgmap));
}
bool pgmap_pfn_valid(struct dev_pagemap *pgmap, unsigned long pfn)
{
int i;
for (i = 0; i < pgmap->nr_range; i++) {
struct range *range = &pgmap->ranges[i];
if (pfn >= PHYS_PFN(range->start) &&
pfn <= PHYS_PFN(range->end))
return pfn >= pfn_first(pgmap, i);
}
return false;
}
static unsigned long pfn_end(struct dev_pagemap *pgmap, int range_id)
{
const struct range *range = &pgmap->ranges[range_id];
return (range->start + range_len(range)) >> PAGE_SHIFT;
}
static unsigned long pfn_len(struct dev_pagemap *pgmap, unsigned long range_id)
{
return (pfn_end(pgmap, range_id) -
pfn_first(pgmap, range_id)) >> pgmap->vmemmap_shift;
}
static void pageunmap_range(struct dev_pagemap *pgmap, int range_id)
{
struct range *range = &pgmap->ranges[range_id];
struct page *first_page;
/* make sure to access a memmap that was actually initialized */
first_page = pfn_to_page(pfn_first(pgmap, range_id));
/* pages are dead and unused, undo the arch mapping */
mem_hotplug_begin();
remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(range->start),
PHYS_PFN(range_len(range)));
if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
__remove_pages(PHYS_PFN(range->start),
PHYS_PFN(range_len(range)), NULL);
} else {
arch_remove_memory(range->start, range_len(range),
pgmap_altmap(pgmap));
kasan_remove_zero_shadow(__va(range->start), range_len(range));
}
mem_hotplug_done();
untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range), true);
pgmap_array_delete(range);
}
void memunmap_pages(struct dev_pagemap *pgmap)
{
int i;
percpu_ref_kill(&pgmap->ref);
if (pgmap->type != MEMORY_DEVICE_PRIVATE &&
pgmap->type != MEMORY_DEVICE_COHERENT)
for (i = 0; i < pgmap->nr_range; i++)
percpu_ref_put_many(&pgmap->ref, pfn_len(pgmap, i));
wait_for_completion(&pgmap->done);
for (i = 0; i < pgmap->nr_range; i++)
pageunmap_range(pgmap, i);
percpu_ref_exit(&pgmap->ref);
WARN_ONCE(pgmap->altmap.alloc, "failed to free all reserved pages\n");
devmap_managed_enable_put(pgmap);
}
EXPORT_SYMBOL_GPL(memunmap_pages);
static void devm_memremap_pages_release(void *data)
{
memunmap_pages(data);
}
static void dev_pagemap_percpu_release(struct percpu_ref *ref)
{
struct dev_pagemap *pgmap = container_of(ref, struct dev_pagemap, ref);
complete(&pgmap->done);
}
static int pagemap_range(struct dev_pagemap *pgmap, struct mhp_params *params,
int range_id, int nid)
{
const bool is_private = pgmap->type == MEMORY_DEVICE_PRIVATE;
struct range *range = &pgmap->ranges[range_id];
struct dev_pagemap *conflict_pgmap;
int error, is_ram;
if (WARN_ONCE(pgmap_altmap(pgmap) && range_id > 0,
"altmap not supported for multiple ranges\n"))
return -EINVAL;
conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->start), NULL);
if (conflict_pgmap) {
WARN(1, "Conflicting mapping in same section\n");
put_dev_pagemap(conflict_pgmap);
return -ENOMEM;
}
conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->end), NULL);
if (conflict_pgmap) {
WARN(1, "Conflicting mapping in same section\n");
put_dev_pagemap(conflict_pgmap);
return -ENOMEM;
}
is_ram = region_intersects(range->start, range_len(range),
IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
if (is_ram != REGION_DISJOINT) {
WARN_ONCE(1, "attempted on %s region %#llx-%#llx\n",
is_ram == REGION_MIXED ? "mixed" : "ram",
range->start, range->end);
return -ENXIO;
}
error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(range->start),
PHYS_PFN(range->end), pgmap, GFP_KERNEL));
if (error)
return error;
if (nid < 0)
nid = numa_mem_id();
error = track_pfn_remap(NULL, ¶ms->pgprot, PHYS_PFN(range->start), 0,
range_len(range));
if (error)
goto err_pfn_remap;
if (!mhp_range_allowed(range->start, range_len(range), !is_private)) {
error = -EINVAL;
goto err_kasan;
}
mem_hotplug_begin();
/*
* For device private memory we call add_pages() as we only need to
* allocate and initialize struct page for the device memory. More-
* over the device memory is un-accessible thus we do not want to
* create a linear mapping for the memory like arch_add_memory()
* would do.
*
* For all other device memory types, which are accessible by
* the CPU, we do want the linear mapping and thus use
* arch_add_memory().
*/
if (is_private) {
error = add_pages(nid, PHYS_PFN(range->start),
PHYS_PFN(range_len(range)), params);
} else {
error = kasan_add_zero_shadow(__va(range->start), range_len(range));
if (error) {
mem_hotplug_done();
goto err_kasan;
}
error = arch_add_memory(nid, range->start, range_len(range),
params);
}
if (!error) {
struct zone *zone;
zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE];
move_pfn_range_to_zone(zone, PHYS_PFN(range->start),
PHYS_PFN(range_len(range)), params->altmap,
MIGRATE_MOVABLE);
}
mem_hotplug_done();
if (error)
goto err_add_memory;
/*
* Initialization of the pages has been deferred until now in order
* to allow us to do the work while not holding the hotplug lock.
*/
memmap_init_zone_device(&NODE_DATA(nid)->node_zones[ZONE_DEVICE],
PHYS_PFN(range->start),
PHYS_PFN(range_len(range)), pgmap);
if (pgmap->type != MEMORY_DEVICE_PRIVATE &&
pgmap->type != MEMORY_DEVICE_COHERENT)
percpu_ref_get_many(&pgmap->ref, pfn_len(pgmap, range_id));
return 0;
err_add_memory:
if (!is_private)
kasan_remove_zero_shadow(__va(range->start), range_len(range));
err_kasan:
untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range), true);
err_pfn_remap:
pgmap_array_delete(range);
return error;
}
/*
* Not device managed version of devm_memremap_pages, undone by
* memunmap_pages(). Please use devm_memremap_pages if you have a struct
* device available.
*/
void *memremap_pages(struct dev_pagemap *pgmap, int nid)
{
struct mhp_params params = {
.altmap = pgmap_altmap(pgmap),
.pgmap = pgmap,
.pgprot = PAGE_KERNEL,
};
const int nr_range = pgmap->nr_range;
int error, i;
if (WARN_ONCE(!nr_range, "nr_range must be specified\n"))
return ERR_PTR(-EINVAL);
switch (pgmap->type) {
case MEMORY_DEVICE_PRIVATE:
if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) {
WARN(1, "Device private memory not supported\n");
return ERR_PTR(-EINVAL);
}
if (!pgmap->ops || !pgmap->ops->migrate_to_ram) {
WARN(1, "Missing migrate_to_ram method\n");
return ERR_PTR(-EINVAL);
}
if (!pgmap->ops->page_free) {
WARN(1, "Missing page_free method\n");
return ERR_PTR(-EINVAL);
}
if (!pgmap->owner) {
WARN(1, "Missing owner\n");
return ERR_PTR(-EINVAL);
}
break;
case MEMORY_DEVICE_COHERENT:
if (!pgmap->ops->page_free) {
WARN(1, "Missing page_free method\n");
return ERR_PTR(-EINVAL);
}
if (!pgmap->owner) {
WARN(1, "Missing owner\n");
return ERR_PTR(-EINVAL);
}
break;
case MEMORY_DEVICE_FS_DAX:
if (IS_ENABLED(CONFIG_FS_DAX_LIMITED)) {
WARN(1, "File system DAX not supported\n");
return ERR_PTR(-EINVAL);
}
params.pgprot = pgprot_decrypted(params.pgprot);
break;
case MEMORY_DEVICE_GENERIC:
break;
case MEMORY_DEVICE_PCI_P2PDMA:
params.pgprot = pgprot_noncached(params.pgprot);
break;
default:
WARN(1, "Invalid pgmap type %d\n", pgmap->type);
break;
}
init_completion(&pgmap->done);
error = percpu_ref_init(&pgmap->ref, dev_pagemap_percpu_release, 0,
GFP_KERNEL);
if (error)
return ERR_PTR(error);
devmap_managed_enable_get(pgmap);
/*
* Clear the pgmap nr_range as it will be incremented for each
* successfully processed range. This communicates how many
* regions to unwind in the abort case.
*/
pgmap->nr_range = 0;
error = 0;
for (i = 0; i < nr_range; i++) {
error = pagemap_range(pgmap, ¶ms, i, nid);
if (error)
break;
pgmap->nr_range++;
}
if (i < nr_range) {
memunmap_pages(pgmap);
pgmap->nr_range = nr_range;
return ERR_PTR(error);
}
return __va(pgmap->ranges[0].start);
}
EXPORT_SYMBOL_GPL(memremap_pages);
/**
* devm_memremap_pages - remap and provide memmap backing for the given resource
* @dev: hosting device for @res
* @pgmap: pointer to a struct dev_pagemap
*
* Notes:
* 1/ At a minimum the range and type members of @pgmap must be initialized
* by the caller before passing it to this function
*
* 2/ The altmap field may optionally be initialized, in which case
* PGMAP_ALTMAP_VALID must be set in pgmap->flags.
*
* 3/ The ref field may optionally be provided, in which pgmap->ref must be
* 'live' on entry and will be killed and reaped at
* devm_memremap_pages_release() time, or if this routine fails.
*
* 4/ range is expected to be a host memory range that could feasibly be
* treated as a "System RAM" range, i.e. not a device mmio range, but
* this is not enforced.
*/
void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
{
int error;
void *ret;
ret = memremap_pages(pgmap, dev_to_node(dev));
if (IS_ERR(ret))
return ret;
error = devm_add_action_or_reset(dev, devm_memremap_pages_release,
pgmap);
if (error)
return ERR_PTR(error);
return ret;
}
EXPORT_SYMBOL_GPL(devm_memremap_pages);
void devm_memunmap_pages(struct device *dev, struct dev_pagemap *pgmap)
{
devm_release_action(dev, devm_memremap_pages_release, pgmap);
}
EXPORT_SYMBOL_GPL(devm_memunmap_pages);
/**
* 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
*
* If @pgmap is non-NULL and covers @pfn it will be returned as-is. If @pgmap
* is non-NULL but does not cover @pfn the reference to it will be released.
*/
struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
struct dev_pagemap *pgmap)
{
resource_size_t phys = PFN_PHYS(pfn);
/*
* In the cached case we're already holding a live reference.
*/
if (pgmap) {
if (phys >= pgmap->range.start && phys <= pgmap->range.end)
return pgmap;
put_dev_pagemap(pgmap);
}
/* fall back to slow path lookup */
rcu_read_lock();
pgmap = xa_load(&pgmap_array, PHYS_PFN(phys));
if (pgmap && !percpu_ref_tryget_live_rcu(&pgmap->ref))
pgmap = NULL;
rcu_read_unlock();
return pgmap;
}
EXPORT_SYMBOL_GPL(get_dev_pagemap);
void free_zone_device_folio(struct folio *folio)
{
if (WARN_ON_ONCE(!folio->page.pgmap->ops ||
!folio->page.pgmap->ops->page_free))
return;
mem_cgroup_uncharge(folio);
/*
* Note: we don't expect anonymous compound pages yet. Once supported
* and we could PTE-map them similar to THP, we'd have to clear
* PG_anon_exclusive on all tail pages.
*/
if (folio_test_anon(folio)) {
VM_BUG_ON_FOLIO(folio_test_large(folio), folio);
__ClearPageAnonExclusive(folio_page(folio, 0));
}
/*
* When a device managed page is freed, the folio->mapping field
* may still contain a (stale) mapping value. For example, the
* lower bits of folio->mapping may still identify the folio as an
* anonymous folio. Ultimately, this entire field is just stale
* and wrong, and it will cause errors if not cleared.
*
* For other types of ZONE_DEVICE pages, migration is either
* handled differently or not done at all, so there is no need
* to clear folio->mapping.
*/
folio->mapping = NULL;
folio->page.pgmap->ops->page_free(folio_page(folio, 0));
if (folio->page.pgmap->type != MEMORY_DEVICE_PRIVATE &&
folio->page.pgmap->type != MEMORY_DEVICE_COHERENT)
/*
* Reset the refcount to 1 to prepare for handing out the page
* again.
*/
folio_set_count(folio, 1);
else
put_dev_pagemap(folio->page.pgmap);
}
void zone_device_page_init(struct page *page)
{
/*
* Drivers shouldn't be allocating pages after calling
* memunmap_pages().
*/
WARN_ON_ONCE(!percpu_ref_tryget_live(&page->pgmap->ref));
set_page_count(page, 1);
lock_page(page);
}
EXPORT_SYMBOL_GPL(zone_device_page_init);
#ifdef CONFIG_FS_DAX
bool __put_devmap_managed_folio_refs(struct folio *folio, int refs)
{
if (folio->page.pgmap->type != MEMORY_DEVICE_FS_DAX)
return false;
/*
* fsdax page refcounts are 1-based, rather than 0-based: if
* refcount is 1, then the page is free and the refcount is
* stable because nobody holds a reference on the page.
*/
if (folio_ref_sub_return(folio, refs) == 1)
wake_up_var(&folio->_refcount);
return true;
}
EXPORT_SYMBOL(__put_devmap_managed_folio_refs);
#endif /* CONFIG_FS_DAX */