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-rw-r--r--mm/Makefile1
-rw-r--r--mm/balloon_compaction.c69
-rw-r--r--mm/compaction.c11
-rw-r--r--mm/hmm.c10
-rw-r--r--mm/kmemleak.c2
-rw-r--r--mm/memory_hotplug.c2
-rw-r--r--mm/memremap.c405
-rw-r--r--mm/migrate.c21
-rw-r--r--mm/slub.c8
-rw-r--r--mm/vmalloc.c9
-rw-r--r--mm/vmscan.c9
11 files changed, 492 insertions, 55 deletions
diff --git a/mm/Makefile b/mm/Makefile
index 338e528ad436..d0b295c3b764 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -102,5 +102,6 @@ obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
obj-$(CONFIG_DEBUG_PAGE_REF) += debug_page_ref.o
obj-$(CONFIG_HARDENED_USERCOPY) += usercopy.o
obj-$(CONFIG_PERCPU_STATS) += percpu-stats.o
+obj-$(CONFIG_ZONE_DEVICE) += memremap.o
obj-$(CONFIG_HMM_MIRROR) += hmm.o
obj-$(CONFIG_MEMFD_CREATE) += memfd.o
diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c
index 83a7b614061f..798275a51887 100644
--- a/mm/balloon_compaction.c
+++ b/mm/balloon_compaction.c
@@ -21,7 +21,6 @@ static void balloon_page_enqueue_one(struct balloon_dev_info *b_dev_info,
* memory corruption is possible and we should stop execution.
*/
BUG_ON(!trylock_page(page));
- list_del(&page->lru);
balloon_page_insert(b_dev_info, page);
unlock_page(page);
__count_vm_event(BALLOON_INFLATE);
@@ -33,8 +32,8 @@ static void balloon_page_enqueue_one(struct balloon_dev_info *b_dev_info,
* @b_dev_info: balloon device descriptor where we will insert a new page to
* @pages: pages to enqueue - allocated using balloon_page_alloc.
*
- * Driver must call it to properly enqueue a balloon pages before definitively
- * removing it from the guest system.
+ * Driver must call this function to properly enqueue balloon pages before
+ * definitively removing them from the guest system.
*
* Return: number of pages that were enqueued.
*/
@@ -47,6 +46,7 @@ size_t balloon_page_list_enqueue(struct balloon_dev_info *b_dev_info,
spin_lock_irqsave(&b_dev_info->pages_lock, flags);
list_for_each_entry_safe(page, tmp, pages, lru) {
+ list_del(&page->lru);
balloon_page_enqueue_one(b_dev_info, page);
n_pages++;
}
@@ -63,12 +63,13 @@ EXPORT_SYMBOL_GPL(balloon_page_list_enqueue);
* @n_req_pages: number of requested pages.
*
* Driver must call this function to properly de-allocate a previous enlisted
- * balloon pages before definetively releasing it back to the guest system.
+ * balloon pages before definitively releasing it back to the guest system.
* This function tries to remove @n_req_pages from the ballooned pages and
* return them to the caller in the @pages list.
*
- * Note that this function may fail to dequeue some pages temporarily empty due
- * to compaction isolated pages.
+ * Note that this function may fail to dequeue some pages even if the balloon
+ * isn't empty - since the page list can be temporarily empty due to compaction
+ * of isolated pages.
*
* Return: number of pages that were added to the @pages list.
*/
@@ -112,12 +113,13 @@ EXPORT_SYMBOL_GPL(balloon_page_list_dequeue);
/*
* balloon_page_alloc - allocates a new page for insertion into the balloon
- * page list.
+ * page list.
+ *
+ * Driver must call this function to properly allocate a new balloon page.
+ * Driver must call balloon_page_enqueue before definitively removing the page
+ * from the guest system.
*
- * Driver must call it to properly allocate a new enlisted balloon page.
- * Driver must call balloon_page_enqueue before definitively removing it from
- * the guest system. This function returns the page address for the recently
- * allocated page or NULL in the case we fail to allocate a new page this turn.
+ * Return: struct page for the allocated page or NULL on allocation failure.
*/
struct page *balloon_page_alloc(void)
{
@@ -128,15 +130,17 @@ struct page *balloon_page_alloc(void)
EXPORT_SYMBOL_GPL(balloon_page_alloc);
/*
- * balloon_page_enqueue - allocates a new page and inserts it into the balloon
- * page list.
- * @b_dev_info: balloon device descriptor where we will insert a new page to
+ * balloon_page_enqueue - inserts a new page into the balloon page list.
+ *
+ * @b_dev_info: balloon device descriptor where we will insert a new page
* @page: new page to enqueue - allocated using balloon_page_alloc.
*
- * Driver must call it to properly enqueue a new allocated balloon page
- * before definitively removing it from the guest system.
- * This function returns the page address for the recently enqueued page or
- * NULL in the case we fail to allocate a new page this turn.
+ * Drivers must call this function to properly enqueue a new allocated balloon
+ * page before definitively removing the page from the guest system.
+ *
+ * Drivers must not call balloon_page_enqueue on pages that have been pushed to
+ * a list with balloon_page_push before removing them with balloon_page_pop. To
+ * enqueue a list of pages, use balloon_page_list_enqueue instead.
*/
void balloon_page_enqueue(struct balloon_dev_info *b_dev_info,
struct page *page)
@@ -151,14 +155,23 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue);
/*
* balloon_page_dequeue - removes a page from balloon's page list and returns
- * the its address to allow the driver release the page.
+ * its address to allow the driver to release the page.
* @b_dev_info: balloon device decriptor where we will grab a page from.
*
- * Driver must call it to properly de-allocate a previous enlisted balloon page
- * before definetively releasing it back to the guest system.
- * This function returns the page address for the recently dequeued page or
- * NULL in the case we find balloon's page list temporarily empty due to
- * compaction isolated pages.
+ * Driver must call this function to properly dequeue a previously enqueued page
+ * before definitively releasing it back to the guest system.
+ *
+ * Caller must perform its own accounting to ensure that this
+ * function is called only if some pages are actually enqueued.
+ *
+ * Note that this function may fail to dequeue some pages even if there are
+ * some enqueued pages - since the page list can be temporarily empty due to
+ * the compaction of isolated pages.
+ *
+ * TODO: remove the caller accounting requirements, and allow caller to wait
+ * until all pages can be dequeued.
+ *
+ * Return: struct page for the dequeued page, or NULL if no page was dequeued.
*/
struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info)
{
@@ -171,9 +184,9 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info)
if (n_pages != 1) {
/*
* If we are unable to dequeue a balloon page because the page
- * list is empty and there is no isolated pages, then something
+ * list is empty and there are no isolated pages, then something
* went out of track and some balloon pages are lost.
- * BUG() here, otherwise the balloon driver may get stuck into
+ * BUG() here, otherwise the balloon driver may get stuck in
* an infinite loop while attempting to release all its pages.
*/
spin_lock_irqsave(&b_dev_info->pages_lock, flags);
@@ -224,8 +237,8 @@ int balloon_page_migrate(struct address_space *mapping,
/*
* We can not easily support the no copy case here so ignore it as it
- * is unlikely to be use with ballon pages. See include/linux/hmm.h for
- * user of the MIGRATE_SYNC_NO_COPY mode.
+ * is unlikely to be used with balloon pages. See include/linux/hmm.h
+ * for a user of the MIGRATE_SYNC_NO_COPY mode.
*/
if (mode == MIGRATE_SYNC_NO_COPY)
return -EINVAL;
diff --git a/mm/compaction.c b/mm/compaction.c
index 9e1b9acb116b..952dc2fb24e5 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -842,13 +842,15 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
/*
* Periodically drop the lock (if held) regardless of its
- * contention, to give chance to IRQs. Abort async compaction
- * if contended.
+ * contention, to give chance to IRQs. Abort completely if
+ * a fatal signal is pending.
*/
if (!(low_pfn % SWAP_CLUSTER_MAX)
&& compact_unlock_should_abort(&pgdat->lru_lock,
- flags, &locked, cc))
- break;
+ flags, &locked, cc)) {
+ low_pfn = 0;
+ goto fatal_pending;
+ }
if (!pfn_valid_within(low_pfn))
goto isolate_fail;
@@ -1060,6 +1062,7 @@ isolate_abort:
trace_mm_compaction_isolate_migratepages(start_pfn, low_pfn,
nr_scanned, nr_isolated);
+fatal_pending:
cc->total_migrate_scanned += nr_scanned;
if (nr_isolated)
count_compact_events(COMPACTISOLATED, nr_isolated);
diff --git a/mm/hmm.c b/mm/hmm.c
index e1eedef129cf..16b6731a34db 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -946,7 +946,7 @@ EXPORT_SYMBOL(hmm_range_unregister);
* @range: range
* Return: -EINVAL if invalid argument, -ENOMEM out of memory, -EPERM invalid
* permission (for instance asking for write and range is read only),
- * -EAGAIN if you need to retry, -EFAULT invalid (ie either no valid
+ * -EBUSY if you need to retry, -EFAULT invalid (ie either no valid
* vma or it is illegal to access that range), number of valid pages
* in range->pfns[] (from range start address).
*
@@ -967,7 +967,7 @@ long hmm_range_snapshot(struct hmm_range *range)
do {
/* If range is no longer valid force retry. */
if (!range->valid)
- return -EAGAIN;
+ return -EBUSY;
vma = find_vma(hmm->mm, start);
if (vma == NULL || (vma->vm_flags & device_vma))
@@ -1062,10 +1062,8 @@ long hmm_range_fault(struct hmm_range *range, bool block)
do {
/* If range is no longer valid force retry. */
- if (!range->valid) {
- up_read(&hmm->mm->mmap_sem);
- return -EAGAIN;
- }
+ if (!range->valid)
+ return -EBUSY;
vma = find_vma(hmm->mm, start);
if (vma == NULL || (vma->vm_flags & device_vma))
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index dbbd518fb6b3..6e9e8cca663e 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -114,7 +114,7 @@
/* GFP bitmask for kmemleak internal allocations */
#define gfp_kmemleak_mask(gfp) (((gfp) & (GFP_KERNEL | GFP_ATOMIC)) | \
__GFP_NORETRY | __GFP_NOMEMALLOC | \
- __GFP_NOWARN | __GFP_NOFAIL)
+ __GFP_NOWARN)
/* scanning area inside a memory block */
struct kmemleak_scan_area {
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 2a9bbddb0e55..c73f09913165 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -132,7 +132,6 @@ static void release_memory_resource(struct resource *res)
return;
release_resource(res);
kfree(res);
- return;
}
#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
@@ -979,7 +978,6 @@ static void rollback_node_hotadd(int nid)
arch_refresh_nodedata(nid, NULL);
free_percpu(pgdat->per_cpu_nodestats);
arch_free_nodedata(pgdat);
- return;
}
diff --git a/mm/memremap.c b/mm/memremap.c
new file mode 100644
index 000000000000..6ee03a816d67
--- /dev/null
+++ b/mm/memremap.c
@@ -0,0 +1,405 @@
+/* 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/mm.h>
+#include <linux/pfn_t.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
+#include <linux/types.h>
+#include <linux/wait_bit.h>
+#include <linux/xarray.h>
+
+static DEFINE_XARRAY(pgmap_array);
+#define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
+#define SECTION_SIZE (1UL << PA_SECTION_SHIFT)
+
+#ifdef CONFIG_DEV_PAGEMAP_OPS
+DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
+EXPORT_SYMBOL(devmap_managed_key);
+static atomic_t devmap_managed_enable;
+
+static void devmap_managed_enable_put(void *data)
+{
+ if (atomic_dec_and_test(&devmap_managed_enable))
+ static_branch_disable(&devmap_managed_key);
+}
+
+static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap)
+{
+ if (!pgmap->ops || !pgmap->ops->page_free) {
+ WARN(1, "Missing page_free method\n");
+ return -EINVAL;
+ }
+
+ if (atomic_inc_return(&devmap_managed_enable) == 1)
+ static_branch_enable(&devmap_managed_key);
+ return devm_add_action_or_reset(dev, devmap_managed_enable_put, NULL);
+}
+#else
+static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap)
+{
+ return -EINVAL;
+}
+#endif /* CONFIG_DEV_PAGEMAP_OPS */
+
+static void pgmap_array_delete(struct resource *res)
+{
+ xa_store_range(&pgmap_array, PHYS_PFN(res->start), PHYS_PFN(res->end),
+ NULL, GFP_KERNEL);
+ synchronize_rcu();
+}
+
+static unsigned long pfn_first(struct dev_pagemap *pgmap)
+{
+ return PHYS_PFN(pgmap->res.start) +
+ vmem_altmap_offset(pgmap_altmap(pgmap));
+}
+
+static unsigned long pfn_end(struct dev_pagemap *pgmap)
+{
+ const struct resource *res = &pgmap->res;
+
+ return (res->start + resource_size(res)) >> PAGE_SHIFT;
+}
+
+static unsigned long pfn_next(unsigned long pfn)
+{
+ if (pfn % 1024 == 0)
+ cond_resched();
+ return pfn + 1;
+}
+
+#define for_each_device_pfn(pfn, map) \
+ for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn))
+
+static void dev_pagemap_kill(struct dev_pagemap *pgmap)
+{
+ if (pgmap->ops && pgmap->ops->kill)
+ pgmap->ops->kill(pgmap);
+ else
+ percpu_ref_kill(pgmap->ref);
+}
+
+static void dev_pagemap_cleanup(struct dev_pagemap *pgmap)
+{
+ if (pgmap->ops && pgmap->ops->cleanup) {
+ pgmap->ops->cleanup(pgmap);
+ } else {
+ wait_for_completion(&pgmap->done);
+ percpu_ref_exit(pgmap->ref);
+ }
+}
+
+static void devm_memremap_pages_release(void *data)
+{
+ struct dev_pagemap *pgmap = data;
+ struct device *dev = pgmap->dev;
+ struct resource *res = &pgmap->res;
+ unsigned long pfn;
+ int nid;
+
+ dev_pagemap_kill(pgmap);
+ for_each_device_pfn(pfn, pgmap)
+ put_page(pfn_to_page(pfn));
+ dev_pagemap_cleanup(pgmap);
+
+ /* pages are dead and unused, undo the arch mapping */
+ nid = page_to_nid(pfn_to_page(PHYS_PFN(res->start)));
+
+ mem_hotplug_begin();
+ if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
+ pfn = PHYS_PFN(res->start);
+ __remove_pages(page_zone(pfn_to_page(pfn)), pfn,
+ PHYS_PFN(resource_size(res)), NULL);
+ } else {
+ arch_remove_memory(nid, res->start, resource_size(res),
+ pgmap_altmap(pgmap));
+ kasan_remove_zero_shadow(__va(res->start), resource_size(res));
+ }
+ mem_hotplug_done();
+
+ untrack_pfn(NULL, PHYS_PFN(res->start), resource_size(res));
+ pgmap_array_delete(res);
+ dev_WARN_ONCE(dev, pgmap->altmap.alloc,
+ "%s: failed to free all reserved pages\n", __func__);
+}
+
+static void dev_pagemap_percpu_release(struct percpu_ref *ref)
+{
+ struct dev_pagemap *pgmap =
+ container_of(ref, struct dev_pagemap, internal_ref);
+
+ complete(&pgmap->done);
+}
+
+/**
+ * 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 res 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/ res 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)
+{
+ struct resource *res = &pgmap->res;
+ struct dev_pagemap *conflict_pgmap;
+ struct mhp_restrictions restrictions = {
+ /*
+ * We do not want any optional features only our own memmap
+ */
+ .altmap = pgmap_altmap(pgmap),
+ };
+ pgprot_t pgprot = PAGE_KERNEL;
+ int error, nid, is_ram;
+ bool need_devmap_managed = true;
+
+ 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);
+ }
+ break;
+ case MEMORY_DEVICE_FS_DAX:
+ if (!IS_ENABLED(CONFIG_ZONE_DEVICE) ||
+ IS_ENABLED(CONFIG_FS_DAX_LIMITED)) {
+ WARN(1, "File system DAX not supported\n");
+ return ERR_PTR(-EINVAL);
+ }
+ break;
+ case MEMORY_DEVICE_DEVDAX:
+ case MEMORY_DEVICE_PCI_P2PDMA:
+ need_devmap_managed = false;
+ break;
+ default:
+ WARN(1, "Invalid pgmap type %d\n", pgmap->type);
+ break;
+ }
+
+ if (!pgmap->ref) {
+ if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup))
+ return ERR_PTR(-EINVAL);
+
+ init_completion(&pgmap->done);
+ error = percpu_ref_init(&pgmap->internal_ref,
+ dev_pagemap_percpu_release, 0, GFP_KERNEL);
+ if (error)
+ return ERR_PTR(error);
+ pgmap->ref = &pgmap->internal_ref;
+ } else {
+ if (!pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup) {
+ WARN(1, "Missing reference count teardown definition\n");
+ return ERR_PTR(-EINVAL);
+ }
+ }
+
+ if (need_devmap_managed) {
+ error = devmap_managed_enable_get(dev, pgmap);
+ if (error)
+ return ERR_PTR(error);
+ }
+
+ conflict_pgmap = get_dev_pagemap(PHYS_PFN(res->start), NULL);
+ if (conflict_pgmap) {
+ dev_WARN(dev, "Conflicting mapping in same section\n");
+ put_dev_pagemap(conflict_pgmap);
+ error = -ENOMEM;
+ goto err_array;
+ }
+
+ conflict_pgmap = get_dev_pagemap(PHYS_PFN(res->end), NULL);
+ if (conflict_pgmap) {
+ dev_WARN(dev, "Conflicting mapping in same section\n");
+ put_dev_pagemap(conflict_pgmap);
+ error = -ENOMEM;
+ goto err_array;
+ }
+
+ is_ram = region_intersects(res->start, resource_size(res),
+ IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
+
+ if (is_ram != REGION_DISJOINT) {
+ WARN_ONCE(1, "%s attempted on %s region %pr\n", __func__,
+ is_ram == REGION_MIXED ? "mixed" : "ram", res);
+ error = -ENXIO;
+ goto err_array;
+ }
+
+ pgmap->dev = dev;
+
+ error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(res->start),
+ PHYS_PFN(res->end), pgmap, GFP_KERNEL));
+ if (error)
+ goto err_array;
+
+ nid = dev_to_node(dev);
+ if (nid < 0)
+ nid = numa_mem_id();
+
+ error = track_pfn_remap(NULL, &pgprot, PHYS_PFN(res->start), 0,
+ resource_size(res));
+ if (error)
+ goto err_pfn_remap;
+
+ 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 (pgmap->type == MEMORY_DEVICE_PRIVATE) {
+ error = add_pages(nid, PHYS_PFN(res->start),
+ PHYS_PFN(resource_size(res)), &restrictions);
+ } else {
+ error = kasan_add_zero_shadow(__va(res->start), resource_size(res));
+ if (error) {
+ mem_hotplug_done();
+ goto err_kasan;
+ }
+
+ error = arch_add_memory(nid, res->start, resource_size(res),
+ &restrictions);
+ }
+
+ if (!error) {
+ struct zone *zone;
+
+ zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE];
+ move_pfn_range_to_zone(zone, PHYS_PFN(res->start),
+ PHYS_PFN(resource_size(res)), restrictions.altmap);
+ }
+
+ 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(res->start),
+ PHYS_PFN(resource_size(res)), pgmap);
+ percpu_ref_get_many(pgmap->ref, pfn_end(pgmap) - pfn_first(pgmap));
+
+ error = devm_add_action_or_reset(dev, devm_memremap_pages_release,
+ pgmap);
+ if (error)
+ return ERR_PTR(error);
+
+ return __va(res->start);
+
+ err_add_memory:
+ kasan_remove_zero_shadow(__va(res->start), resource_size(res));
+ err_kasan:
+ untrack_pfn(NULL, PHYS_PFN(res->start), resource_size(res));
+ err_pfn_remap:
+ pgmap_array_delete(res);
+ err_array:
+ dev_pagemap_kill(pgmap);
+ dev_pagemap_cleanup(pgmap);
+ return ERR_PTR(error);
+}
+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);
+
+unsigned long vmem_altmap_offset(struct vmem_altmap *altmap)
+{
+ /* number of pfns from base where pfn_to_page() is valid */
+ if (altmap)
+ return altmap->reserve + altmap->free;
+ return 0;
+}
+
+void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns)
+{
+ altmap->alloc -= nr_pfns;
+}
+
+/**
+ * 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->res.start && phys <= pgmap->res.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(pgmap->ref))
+ pgmap = NULL;
+ rcu_read_unlock();
+
+ return pgmap;
+}
+EXPORT_SYMBOL_GPL(get_dev_pagemap);
+
+#ifdef CONFIG_DEV_PAGEMAP_OPS
+void __put_devmap_managed_page(struct page *page)
+{
+ int count = page_ref_dec_return(page);
+
+ /*
+ * If refcount is 1 then page is freed and refcount is stable as nobody
+ * holds a reference on the page.
+ */
+ if (count == 1) {
+ /* Clear Active bit in case of parallel mark_page_accessed */
+ __ClearPageActive(page);
+ __ClearPageWaiters(page);
+
+ mem_cgroup_uncharge(page);
+
+ page->pgmap->ops->page_free(page);
+ } else if (!count)
+ __put_page(page);
+}
+EXPORT_SYMBOL(__put_devmap_managed_page);
+#endif /* CONFIG_DEV_PAGEMAP_OPS */
diff --git a/mm/migrate.c b/mm/migrate.c
index 8992741f10aa..a42858d8e00b 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -767,12 +767,12 @@ recheck_buffers:
}
bh = bh->b_this_page;
} while (bh != head);
- spin_unlock(&mapping->private_lock);
if (busy) {
if (invalidated) {
rc = -EAGAIN;
goto unlock_buffers;
}
+ spin_unlock(&mapping->private_lock);
invalidate_bh_lrus();
invalidated = true;
goto recheck_buffers;
@@ -805,6 +805,8 @@ recheck_buffers:
rc = MIGRATEPAGE_SUCCESS;
unlock_buffers:
+ if (check_refs)
+ spin_unlock(&mapping->private_lock);
bh = head;
do {
unlock_buffer(bh);
@@ -2338,16 +2340,13 @@ next:
static void migrate_vma_collect(struct migrate_vma *migrate)
{
struct mmu_notifier_range range;
- struct mm_walk mm_walk;
-
- mm_walk.pmd_entry = migrate_vma_collect_pmd;
- mm_walk.pte_entry = NULL;
- mm_walk.pte_hole = migrate_vma_collect_hole;
- mm_walk.hugetlb_entry = NULL;
- mm_walk.test_walk = NULL;
- mm_walk.vma = migrate->vma;
- mm_walk.mm = migrate->vma->vm_mm;
- mm_walk.private = migrate;
+ struct mm_walk mm_walk = {
+ .pmd_entry = migrate_vma_collect_pmd,
+ .pte_hole = migrate_vma_collect_hole,
+ .vma = migrate->vma,
+ .mm = migrate->vma->vm_mm,
+ .private = migrate,
+ };
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, NULL, mm_walk.mm,
migrate->start,
diff --git a/mm/slub.c b/mm/slub.c
index e6c030e47364..8834563cdb4b 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1432,7 +1432,9 @@ static inline bool slab_free_freelist_hook(struct kmem_cache *s,
void *old_tail = *tail ? *tail : *head;
int rsize;
- if (slab_want_init_on_free(s))
+ if (slab_want_init_on_free(s)) {
+ void *p = NULL;
+
do {
object = next;
next = get_freepointer(s, object);
@@ -1445,8 +1447,10 @@ static inline bool slab_free_freelist_hook(struct kmem_cache *s,
: 0;
memset((char *)object + s->inuse, 0,
s->size - s->inuse - rsize);
- set_freepointer(s, object, next);
+ set_freepointer(s, object, p);
+ p = object;
} while (object != old_tail);
+ }
/*
* Compiler cannot detect this function can be removed if slab_free_hook()
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 4fa8d84599b0..e0fc963acc41 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1259,6 +1259,12 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
return false;
/*
+ * First make sure the mappings are removed from all page-tables
+ * before they are freed.
+ */
+ vmalloc_sync_all();
+
+ /*
* TODO: to calculate a flush range without looping.
* The list can be up to lazy_max_pages() elements.
*/
@@ -3038,6 +3044,9 @@ EXPORT_SYMBOL(remap_vmalloc_range);
/*
* Implement a stub for vmalloc_sync_all() if the architecture chose not to
* have one.
+ *
+ * The purpose of this function is to make sure the vmalloc area
+ * mappings are identical in all page-tables in the system.
*/
void __weak vmalloc_sync_all(void)
{
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 44df66a98f2a..dbdc46a84f63 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -699,7 +699,14 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid,
unsigned long ret, freed = 0;
struct shrinker *shrinker;
- if (!mem_cgroup_is_root(memcg))
+ /*
+ * The root memcg might be allocated even though memcg is disabled
+ * via "cgroup_disable=memory" boot parameter. This could make
+ * mem_cgroup_is_root() return false, then just run memcg slab
+ * shrink, but skip global shrink. This may result in premature
+ * oom.
+ */
+ if (!mem_cgroup_disabled() && !mem_cgroup_is_root(memcg))
return shrink_slab_memcg(gfp_mask, nid, memcg, priority);
if (!down_read_trylock(&shrinker_rwsem))