Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
   from hotplugged memory rather than only from main memory. Series
   "implement "memmap on memory" feature on s390".

 - More folio conversions from Matthew Wilcox in the series

	"Convert memcontrol charge moving to use folios"
	"mm: convert mm counter to take a folio"

 - Chengming Zhou has optimized zswap's rbtree locking, providing
   significant reductions in system time and modest but measurable
   reductions in overall runtimes. The series is "mm/zswap: optimize the
   scalability of zswap rb-tree".

 - Chengming Zhou has also provided the series "mm/zswap: optimize zswap
   lru list" which provides measurable runtime benefits in some
   swap-intensive situations.

 - And Chengming Zhou further optimizes zswap in the series "mm/zswap:
   optimize for dynamic zswap_pools". Measured improvements are modest.

 - zswap cleanups and simplifications from Yosry Ahmed in the series
   "mm: zswap: simplify zswap_swapoff()".

 - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
   contributed several DAX cleanups as well as adding a sysfs tunable to
   control the memmap_on_memory setting when the dax device is
   hotplugged as system memory.

 - Johannes Weiner has added the large series "mm: zswap: cleanups",
   which does that.

 - More DAMON work from SeongJae Park in the series

	"mm/damon: make DAMON debugfs interface deprecation unignorable"
	"selftests/damon: add more tests for core functionalities and corner cases"
	"Docs/mm/damon: misc readability improvements"
	"mm/damon: let DAMOS feeds and tame/auto-tune itself"

 - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
   extension" Rakie Kim has developed a new mempolicy interleaving
   policy wherein we allocate memory across nodes in a weighted fashion
   rather than uniformly. This is beneficial in heterogeneous memory
   environments appearing with CXL.

 - Christophe Leroy has contributed some cleanup and consolidation work
   against the ARM pagetable dumping code in the series "mm: ptdump:
   Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".

 - Luis Chamberlain has added some additional xarray selftesting in the
   series "test_xarray: advanced API multi-index tests".

 - Muhammad Usama Anjum has reworked the selftest code to make its
   human-readable output conform to the TAP ("Test Anything Protocol")
   format. Amongst other things, this opens up the use of third-party
   tools to parse and process out selftesting results.

 - Ryan Roberts has added fork()-time PTE batching of THP ptes in the
   series "mm/memory: optimize fork() with PTE-mapped THP". Mainly
   targeted at arm64, this significantly speeds up fork() when the
   process has a large number of pte-mapped folios.

 - David Hildenbrand also gets in on the THP pte batching game in his
   series "mm/memory: optimize unmap/zap with PTE-mapped THP". It
   implements batching during munmap() and other pte teardown
   situations. The microbenchmark improvements are nice.

 - And in the series "Transparent Contiguous PTEs for User Mappings"
   Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte
   mappings"). Kernel build times on arm64 improved nicely. Ryan's
   series "Address some contpte nits" provides some followup work.

 - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
   fixed an obscure hugetlb race which was causing unnecessary page
   faults. He has also added a reproducer under the selftest code.

 - In the series "selftests/mm: Output cleanups for the compaction
   test", Mark Brown did what the title claims.

 - Kinsey Ho has added the series "mm/mglru: code cleanup and
   refactoring".

 - Even more zswap material from Nhat Pham. The series "fix and extend
   zswap kselftests" does as claimed.

 - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
   regression" Mathieu Desnoyers has cleaned up and fixed rather a mess
   in our handling of DAX on archiecctures which have virtually aliasing
   data caches. The arm architecture is the main beneficiary.

 - Lokesh Gidra's series "per-vma locks in userfaultfd" provides
   dramatic improvements in worst-case mmap_lock hold times during
   certain userfaultfd operations.

 - Some page_owner enhancements and maintenance work from Oscar Salvador
   in his series

	"page_owner: print stacks and their outstanding allocations"
	"page_owner: Fixup and cleanup"

 - Uladzislau Rezki has contributed some vmalloc scalability
   improvements in his series "Mitigate a vmap lock contention". It
   realizes a 12x improvement for a certain microbenchmark.

 - Some kexec/crash cleanup work from Baoquan He in the series "Split
   crash out from kexec and clean up related config items".

 - Some zsmalloc maintenance work from Chengming Zhou in the series

	"mm/zsmalloc: fix and optimize objects/page migration"
	"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"

 - Zi Yan has taught the MM to perform compaction on folios larger than
   order=0. This a step along the path to implementaton of the merging
   of large anonymous folios. The series is named "Enable >0 order folio
   memory compaction".

 - Christoph Hellwig has done quite a lot of cleanup work in the
   pagecache writeback code in his series "convert write_cache_pages()
   to an iterator".

 - Some modest hugetlb cleanups and speedups in Vishal Moola's series
   "Handle hugetlb faults under the VMA lock".

 - Zi Yan has changed the page splitting code so we can split huge pages
   into sizes other than order-0 to better utilize large folios. The
   series is named "Split a folio to any lower order folios".

 - David Hildenbrand has contributed the series "mm: remove
   total_mapcount()", a cleanup.

 - Matthew Wilcox has sought to improve the performance of bulk memory
   freeing in his series "Rearrange batched folio freeing".

 - Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
   provides large improvements in bootup times on large machines which
   are configured to use large numbers of hugetlb pages.

 - Matthew Wilcox's series "PageFlags cleanups" does that.

 - Qi Zheng's series "minor fixes and supplement for ptdesc" does that
   also. S390 is affected.

 - Cleanups to our pagemap utility functions from Peter Xu in his series
   "mm/treewide: Replace pXd_large() with pXd_leaf()".

 - Nico Pache has fixed a few things with our hugepage selftests in his
   series "selftests/mm: Improve Hugepage Test Handling in MM
   Selftests".

 - Also, of course, many singleton patches to many things. Please see
   the individual changelogs for details.

* tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits)
  mm/zswap: remove the memcpy if acomp is not sleepable
  crypto: introduce: acomp_is_async to expose if comp drivers might sleep
  memtest: use {READ,WRITE}_ONCE in memory scanning
  mm: prohibit the last subpage from reusing the entire large folio
  mm: recover pud_leaf() definitions in nopmd case
  selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements
  selftests/mm: skip uffd hugetlb tests with insufficient hugepages
  selftests/mm: dont fail testsuite due to a lack of hugepages
  mm/huge_memory: skip invalid debugfs new_order input for folio split
  mm/huge_memory: check new folio order when split a folio
  mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure
  mm: add an explicit smp_wmb() to UFFDIO_CONTINUE
  mm: fix list corruption in put_pages_list
  mm: remove folio from deferred split list before uncharging it
  filemap: avoid unnecessary major faults in filemap_fault()
  mm,page_owner: drop unnecessary check
  mm,page_owner: check for null stack_record before bumping its refcount
  mm: swap: fix race between free_swap_and_cache() and swapoff()
  mm/treewide: align up pXd_leaf() retval across archs
  mm/treewide: drop pXd_large()
  ...

1 files changed, 813 insertions, 267 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 1e36322d83d8..22aa63f4ef63 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -800,17 +800,9 @@ EXPORT_SYMBOL(vmalloc_to_pfn);
 #define DEBUG_AUGMENT_LOWEST_MATCH_CHECK 0
 
 
-static DEFINE_SPINLOCK(vmap_area_lock);
 static DEFINE_SPINLOCK(free_vmap_area_lock);
-/* Export for kexec only */
-LIST_HEAD(vmap_area_list);
-static struct rb_root vmap_area_root = RB_ROOT;
 static bool vmap_initialized __read_mostly;
 
-static struct rb_root purge_vmap_area_root = RB_ROOT;
-static LIST_HEAD(purge_vmap_area_list);
-static DEFINE_SPINLOCK(purge_vmap_area_lock);
-
 /*
  * This kmem_cache is used for vmap_area objects. Instead of
  * allocating from slab we reuse an object from this cache to
@@ -844,6 +836,129 @@ static struct rb_root free_vmap_area_root = RB_ROOT;
  */
 static DEFINE_PER_CPU(struct vmap_area *, ne_fit_preload_node);
 
+/*
+ * This structure defines a single, solid model where a list and
+ * rb-tree are part of one entity protected by the lock. Nodes are
+ * sorted in ascending order, thus for O(1) access to left/right
+ * neighbors a list is used as well as for sequential traversal.
+ */
+struct rb_list {
+	struct rb_root root;
+	struct list_head head;
+	spinlock_t lock;
+};
+
+/*
+ * A fast size storage contains VAs up to 1M size. A pool consists
+ * of linked between each other ready to go VAs of certain sizes.
+ * An index in the pool-array corresponds to number of pages + 1.
+ */
+#define MAX_VA_SIZE_PAGES 256
+
+struct vmap_pool {
+	struct list_head head;
+	unsigned long len;
+};
+
+/*
+ * An effective vmap-node logic. Users make use of nodes instead
+ * of a global heap. It allows to balance an access and mitigate
+ * contention.
+ */
+static struct vmap_node {
+	/* Simple size segregated storage. */
+	struct vmap_pool pool[MAX_VA_SIZE_PAGES];
+	spinlock_t pool_lock;
+	bool skip_populate;
+
+	/* Bookkeeping data of this node. */
+	struct rb_list busy;
+	struct rb_list lazy;
+
+	/*
+	 * Ready-to-free areas.
+	 */
+	struct list_head purge_list;
+	struct work_struct purge_work;
+	unsigned long nr_purged;
+} single;
+
+/*
+ * Initial setup consists of one single node, i.e. a balancing
+ * is fully disabled. Later on, after vmap is initialized these
+ * parameters are updated based on a system capacity.
+ */
+static struct vmap_node *vmap_nodes = &single;
+static __read_mostly unsigned int nr_vmap_nodes = 1;
+static __read_mostly unsigned int vmap_zone_size = 1;
+
+static inline unsigned int
+addr_to_node_id(unsigned long addr)
+{
+	return (addr / vmap_zone_size) % nr_vmap_nodes;
+}
+
+static inline struct vmap_node *
+addr_to_node(unsigned long addr)
+{
+	return &vmap_nodes[addr_to_node_id(addr)];
+}
+
+static inline struct vmap_node *
+id_to_node(unsigned int id)
+{
+	return &vmap_nodes[id % nr_vmap_nodes];
+}
+
+/*
+ * We use the value 0 to represent "no node", that is why
+ * an encoded value will be the node-id incremented by 1.
+ * It is always greater then 0. A valid node_id which can
+ * be encoded is [0:nr_vmap_nodes - 1]. If a passed node_id
+ * is not valid 0 is returned.
+ */
+static unsigned int
+encode_vn_id(unsigned int node_id)
+{
+	/* Can store U8_MAX [0:254] nodes. */
+	if (node_id < nr_vmap_nodes)
+		return (node_id + 1) << BITS_PER_BYTE;
+
+	/* Warn and no node encoded. */
+	WARN_ONCE(1, "Encode wrong node id (%u)\n", node_id);
+	return 0;
+}
+
+/*
+ * Returns an encoded node-id, the valid range is within
+ * [0:nr_vmap_nodes-1] values. Otherwise nr_vmap_nodes is
+ * returned if extracted data is wrong.
+ */
+static unsigned int
+decode_vn_id(unsigned int val)
+{
+	unsigned int node_id = (val >> BITS_PER_BYTE) - 1;
+
+	/* Can store U8_MAX [0:254] nodes. */
+	if (node_id < nr_vmap_nodes)
+		return node_id;
+
+	/* If it was _not_ zero, warn. */
+	WARN_ONCE(node_id != UINT_MAX,
+		"Decode wrong node id (%d)\n", node_id);
+
+	return nr_vmap_nodes;
+}
+
+static bool
+is_vn_id_valid(unsigned int node_id)
+{
+	if (node_id < nr_vmap_nodes)
+		return true;
+
+	return false;
+}
+
 static __always_inline unsigned long
 va_size(struct vmap_area *va)
 {
@@ -875,10 +990,11 @@ unsigned long vmalloc_nr_pages(void)
 }
 
 /* Look up the first VA which satisfies addr < va_end, NULL if none. */
-static struct vmap_area *find_vmap_area_exceed_addr(unsigned long addr)
+static struct vmap_area *
+__find_vmap_area_exceed_addr(unsigned long addr, struct rb_root *root)
 {
 	struct vmap_area *va = NULL;
-	struct rb_node *n = vmap_area_root.rb_node;
+	struct rb_node *n = root->rb_node;
 
 	addr = (unsigned long)kasan_reset_tag((void *)addr);
 
@@ -899,6 +1015,41 @@ static struct vmap_area *find_vmap_area_exceed_addr(unsigned long addr)
 	return va;
 }
 
+/*
+ * Returns a node where a first VA, that satisfies addr < va_end, resides.
+ * If success, a node is locked. A user is responsible to unlock it when a
+ * VA is no longer needed to be accessed.
+ *
+ * Returns NULL if nothing found.
+ */
+static struct vmap_node *
+find_vmap_area_exceed_addr_lock(unsigned long addr, struct vmap_area **va)
+{
+	struct vmap_node *vn, *va_node = NULL;
+	struct vmap_area *va_lowest;
+	int i;
+
+	for (i = 0; i < nr_vmap_nodes; i++) {
+		vn = &vmap_nodes[i];
+
+		spin_lock(&vn->busy.lock);
+		va_lowest = __find_vmap_area_exceed_addr(addr, &vn->busy.root);
+		if (va_lowest) {
+			if (!va_node || va_lowest->va_start < (*va)->va_start) {
+				if (va_node)
+					spin_unlock(&va_node->busy.lock);
+
+				*va = va_lowest;
+				va_node = vn;
+				continue;
+			}
+		}
+		spin_unlock(&vn->busy.lock);
+	}
+
+	return va_node;
+}
+
 static struct vmap_area *__find_vmap_area(unsigned long addr, struct rb_root *root)
 {
 	struct rb_node *n = root->rb_node;
@@ -1454,9 +1605,9 @@ classify_va_fit_type(struct vmap_area *va,
 }
 
 static __always_inline int
-adjust_va_to_fit_type(struct rb_root *root, struct list_head *head,
-		      struct vmap_area *va, unsigned long nva_start_addr,
-		      unsigned long size)
+va_clip(struct rb_root *root, struct list_head *head,
+		struct vmap_area *va, unsigned long nva_start_addr,
+		unsigned long size)
 {
 	struct vmap_area *lva = NULL;
 	enum fit_type type = classify_va_fit_type(va, nva_start_addr, size);
@@ -1553,6 +1704,32 @@ adjust_va_to_fit_type(struct rb_root *root, struct list_head *head,
 	return 0;
 }
 
+static unsigned long
+va_alloc(struct vmap_area *va,
+		struct rb_root *root, struct list_head *head,
+		unsigned long size, unsigned long align,
+		unsigned long vstart, unsigned long vend)
+{
+	unsigned long nva_start_addr;
+	int ret;
+
+	if (va->va_start > vstart)
+		nva_start_addr = ALIGN(va->va_start, align);
+	else
+		nva_start_addr = ALIGN(vstart, align);
+
+	/* Check the "vend" restriction. */
+	if (nva_start_addr + size > vend)
+		return vend;
+
+	/* Update the free vmap_area. */
+	ret = va_clip(root, head, va, nva_start_addr, size);
+	if (WARN_ON_ONCE(ret))
+		return vend;
+
+	return nva_start_addr;
+}
+
 /*
  * Returns a start address of the newly allocated area, if success.
  * Otherwise a vend is returned that indicates failure.
@@ -1565,7 +1742,6 @@ __alloc_vmap_area(struct rb_root *root, struct list_head *head,
 	bool adjust_search_size = true;
 	unsigned long nva_start_addr;
 	struct vmap_area *va;
-	int ret;
 
 	/*
 	 * Do not adjust when:
@@ -1583,18 +1759,8 @@ __alloc_vmap_area(struct rb_root *root, struct list_head *head,
 	if (unlikely(!va))
 		return vend;
 
-	if (va->va_start > vstart)
-		nva_start_addr = ALIGN(va->va_start, align);
-	else
-		nva_start_addr = ALIGN(vstart, align);
-
-	/* Check the "vend" restriction. */
-	if (nva_start_addr + size > vend)
-		return vend;
-
-	/* Update the free vmap_area. */
-	ret = adjust_va_to_fit_type(root, head, va, nva_start_addr, size);
-	if (WARN_ON_ONCE(ret))
+	nva_start_addr = va_alloc(va, root, head, size, align, vstart, vend);
+	if (nva_start_addr == vend)
 		return vend;
 
 #if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
@@ -1609,12 +1775,14 @@ __alloc_vmap_area(struct rb_root *root, struct list_head *head,
  */
 static void free_vmap_area(struct vmap_area *va)
 {
+	struct vmap_node *vn = addr_to_node(va->va_start);
+
 	/*
 	 * Remove from the busy tree/list.
 	 */
-	spin_lock(&vmap_area_lock);
-	unlink_va(va, &vmap_area_root);
-	spin_unlock(&vmap_area_lock);
+	spin_lock(&vn->busy.lock);
+	unlink_va(va, &vn->busy.root);
+	spin_unlock(&vn->busy.lock);
 
 	/*
 	 * Insert/Merge it back to the free tree/list.
@@ -1647,6 +1815,104 @@ preload_this_cpu_lock(spinlock_t *lock, gfp_t gfp_mask, int node)
 		kmem_cache_free(vmap_area_cachep, va);
 }
 
+static struct vmap_pool *
+size_to_va_pool(struct vmap_node *vn, unsigned long size)
+{
+	unsigned int idx = (size - 1) / PAGE_SIZE;
+
+	if (idx < MAX_VA_SIZE_PAGES)
+		return &vn->pool[idx];
+
+	return NULL;
+}
+
+static bool
+node_pool_add_va(struct vmap_node *n, struct vmap_area *va)
+{
+	struct vmap_pool *vp;
+
+	vp = size_to_va_pool(n, va_size(va));
+	if (!vp)
+		return false;
+
+	spin_lock(&n->pool_lock);
+	list_add(&va->list, &vp->head);
+	WRITE_ONCE(vp->len, vp->len + 1);
+	spin_unlock(&n->pool_lock);
+
+	return true;
+}
+
+static struct vmap_area *
+node_pool_del_va(struct vmap_node *vn, unsigned long size,
+		unsigned long align, unsigned long vstart,
+		unsigned long vend)
+{
+	struct vmap_area *va = NULL;
+	struct vmap_pool *vp;
+	int err = 0;
+
+	vp = size_to_va_pool(vn, size);
+	if (!vp || list_empty(&vp->head))
+		return NULL;
+
+	spin_lock(&vn->pool_lock);
+	if (!list_empty(&vp->head)) {
+		va = list_first_entry(&vp->head, struct vmap_area, list);
+
+		if (IS_ALIGNED(va->va_start, align)) {
+			/*
+			 * Do some sanity check and emit a warning
+			 * if one of below checks detects an error.
+			 */
+			err |= (va_size(va) != size);
+			err |= (va->va_start < vstart);
+			err |= (va->va_end > vend);
+
+			if (!WARN_ON_ONCE(err)) {
+				list_del_init(&va->list);
+				WRITE_ONCE(vp->len, vp->len - 1);
+			} else {
+				va = NULL;
+			}
+		} else {
+			list_move_tail(&va->list, &vp->head);
+			va = NULL;
+		}
+	}
+	spin_unlock(&vn->pool_lock);
+
+	return va;
+}
+
+static struct vmap_area *
+node_alloc(unsigned long size, unsigned long align,
+		unsigned long vstart, unsigned long vend,
+		unsigned long *addr, unsigned int *vn_id)
+{
+	struct vmap_area *va;
+
+	*vn_id = 0;
+	*addr = vend;
+
+	/*
+	 * Fallback to a global heap if not vmalloc or there
+	 * is only one node.
+	 */
+	if (vstart != VMALLOC_START || vend != VMALLOC_END ||
+			nr_vmap_nodes == 1)
+		return NULL;
+
+	*vn_id = raw_smp_processor_id() % nr_vmap_nodes;
+	va = node_pool_del_va(id_to_node(*vn_id), size, align, vstart, vend);
+	*vn_id = encode_vn_id(*vn_id);
+
+	if (va)
+		*addr = va->va_start;
+
+	return va;
+}
+
 /*
  * Allocate a region of KVA of the specified size and alignment, within the
  * vstart and vend.
@@ -1657,9 +1923,11 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
 				int node, gfp_t gfp_mask,
 				unsigned long va_flags)
 {
+	struct vmap_node *vn;
 	struct vmap_area *va;
 	unsigned long freed;
 	unsigned long addr;
+	unsigned int vn_id;
 	int purged = 0;
 	int ret;
 
@@ -1670,23 +1938,37 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
 		return ERR_PTR(-EBUSY);
 
 	might_sleep();
-	gfp_mask = gfp_mask & GFP_RECLAIM_MASK;
-
-	va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
-	if (unlikely(!va))
-		return ERR_PTR(-ENOMEM);
 
 	/*
-	 * Only scan the relevant parts containing pointers to other objects
-	 * to avoid false negatives.
+	 * If a VA is obtained from a global heap(if it fails here)
+	 * it is anyway marked with this "vn_id" so it is returned
+	 * to this pool's node later. Such way gives a possibility
+	 * to populate pools based on users demand.
+	 *
+	 * On success a ready to go VA is returned.
 	 */
-	kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
+	va = node_alloc(size, align, vstart, vend, &addr, &vn_id);
+	if (!va) {
+		gfp_mask = gfp_mask & GFP_RECLAIM_MASK;
+
+		va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
+		if (unlikely(!va))
+			return ERR_PTR(-ENOMEM);
+
+		/*
+		 * Only scan the relevant parts containing pointers to other objects
+		 * to avoid false negatives.
+		 */
+		kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
+	}
 
 retry:
-	preload_this_cpu_lock(&free_vmap_area_lock, gfp_mask, node);
-	addr = __alloc_vmap_area(&free_vmap_area_root, &free_vmap_area_list,
-		size, align, vstart, vend);
-	spin_unlock(&free_vmap_area_lock);
+	if (addr == vend) {
+		preload_this_cpu_lock(&free_vmap_area_lock, gfp_mask, node);
+		addr = __alloc_vmap_area(&free_vmap_area_root, &free_vmap_area_list,
+			size, align, vstart, vend);
+		spin_unlock(&free_vmap_area_lock);
+	}
 
 	trace_alloc_vmap_area(addr, size, align, vstart, vend, addr == vend);
 
@@ -1700,11 +1982,13 @@ retry:
 	va->va_start = addr;
 	va->va_end = addr + size;
 	va->vm = NULL;
-	va->flags = va_flags;
+	va->flags = (va_flags | vn_id);
 
-	spin_lock(&vmap_area_lock);
-	insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
-	spin_unlock(&vmap_area_lock);
+	vn = addr_to_node(va->va_start);
+
+	spin_lock(&vn->busy.lock);
+	insert_vmap_area(va, &vn->busy.root, &vn->busy.head);
+	spin_unlock(&vn->busy.lock);
 
 	BUG_ON(!IS_ALIGNED(va->va_start, align));
 	BUG_ON(va->va_start < vstart);
@@ -1789,70 +2073,199 @@ static DEFINE_MUTEX(vmap_purge_lock);
 
 /* for per-CPU blocks */
 static void purge_fragmented_blocks_allcpus(void);
+static cpumask_t purge_nodes;
 
-/*
- * Purges all lazily-freed vmap areas.
- */
-static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
+static void
+reclaim_list_global(struct list_head *head)
 {
-	unsigned long resched_threshold;
-	unsigned int num_purged_areas = 0;
-	struct list_head local_purge_list;
-	struct vmap_area *va, *n_va;
+	struct vmap_area *va, *n;
 
-	lockdep_assert_held(&vmap_purge_lock);
+	if (list_empty(head))
+		return;
 
-	spin_lock(&purge_vmap_area_lock);
-	purge_vmap_area_root = RB_ROOT;
-	list_replace_init(&purge_vmap_area_list, &local_purge_list);
-	spin_unlock(&purge_vmap_area_lock);
+	spin_lock(&free_vmap_area_lock);
+	list_for_each_entry_safe(va, n, head, list)
+		merge_or_add_vmap_area_augment(va,
+			&free_vmap_area_root, &free_vmap_area_list);
+	spin_unlock(&free_vmap_area_lock);
+}
 
-	if (unlikely(list_empty(&local_purge_list)))
-		goto out;
+static void
+decay_va_pool_node(struct vmap_node *vn, bool full_decay)
+{
+	struct vmap_area *va, *nva;
+	struct list_head decay_list;
+	struct rb_root decay_root;
+	unsigned long n_decay;
+	int i;
 
-	start = min(start,
-		list_first_entry(&local_purge_list,
-			struct vmap_area, list)->va_start);
+	decay_root = RB_ROOT;
+	INIT_LIST_HEAD(&decay_list);
 
-	end = max(end,
-		list_last_entry(&local_purge_list,
-			struct vmap_area, list)->va_end);
+	for (i = 0; i < MAX_VA_SIZE_PAGES; i++) {
+		struct list_head tmp_list;
 
-	flush_tlb_kernel_range(start, end);
-	resched_threshold = lazy_max_pages() << 1;
+		if (list_empty(&vn->pool[i].head))
+			continue;
 
-	spin_lock(&free_vmap_area_lock);
-	list_for_each_entry_safe(va, n_va, &local_purge_list, list) {
-		unsigned long nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
-		unsigned long orig_start = va->va_start;
-		unsigned long orig_end = va->va_end;
+		INIT_LIST_HEAD(&tmp_list);
+
+		/* Detach the pool, so no-one can access it. */
+		spin_lock(&vn->pool_lock);
+		list_replace_init(&vn->pool[i].head, &tmp_list);
+		spin_unlock(&vn->pool_lock);
+
+		if (full_decay)
+			WRITE_ONCE(vn->pool[i].len, 0);
+
+		/* Decay a pool by ~25% out of left objects. */
+		n_decay = vn->pool[i].len >> 2;
+
+		list_for_each_entry_safe(va, nva, &tmp_list, list) {
+			list_del_init(&va->list);
+			merge_or_add_vmap_area(va, &decay_root, &decay_list);
+
+			if (!full_decay) {
+				WRITE_ONCE(vn->pool[i].len, vn->pool[i].len - 1);
+
+				if (!--n_decay)
+					break;
+			}
+		}
 
 		/*
-		 * Finally insert or merge lazily-freed area. It is
-		 * detached and there is no need to "unlink" it from
-		 * anything.
+		 * Attach the pool back if it has been partly decayed.
+		 * Please note, it is supposed that nobody(other contexts)
+		 * can populate the pool therefore a simple list replace
+		 * operation takes place here.
 		 */
-		va = merge_or_add_vmap_area_augment(va, &free_vmap_area_root,
-				&free_vmap_area_list);
+		if (!full_decay && !list_empty(&tmp_list)) {
+			spin_lock(&vn->pool_lock);
+			list_replace_init(&tmp_list, &vn->pool[i].head);
+			spin_unlock(&vn->pool_lock);
+		}
+	}
 
-		if (!va)
-			continue;
+	reclaim_list_global(&decay_list);
+}
+
+static void purge_vmap_node(struct work_struct *work)
+{
+	struct vmap_node *vn = container_of(work,
+		struct vmap_node, purge_work);
+	struct vmap_area *va, *n_va;
+	LIST_HEAD(local_list);
+
+	vn->nr_purged = 0;
+
+	list_for_each_entry_safe(va, n_va, &vn->purge_list, list) {
+		unsigned long nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
+		unsigned long orig_start = va->va_start;
+		unsigned long orig_end = va->va_end;
+		unsigned int vn_id = decode_vn_id(va->flags);
+
+		list_del_init(&va->list);
 
 		if (is_vmalloc_or_module_addr((void *)orig_start))
 			kasan_release_vmalloc(orig_start, orig_end,
 					      va->va_start, va->va_end);
 
 		atomic_long_sub(nr, &vmap_lazy_nr);
-		num_purged_areas++;
+		vn->nr_purged++;
 
-		if (atomic_long_read(&vmap_lazy_nr) < resched_threshold)
-			cond_resched_lock(&free_vmap_area_lock);
+		if (is_vn_id_valid(vn_id) && !vn->skip_populate)
+			if (node_pool_add_va(vn, va))
+				continue;
+
+		/* Go back to global. */
+		list_add(&va->list, &local_list);
 	}
-	spin_unlock(&free_vmap_area_lock);
 
-out:
-	trace_purge_vmap_area_lazy(start, end, num_purged_areas);
-	return num_purged_areas > 0;
+	reclaim_list_global(&local_list);
+}
+
+/*
+ * Purges all lazily-freed vmap areas.
+ */
+static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end,
+		bool full_pool_decay)
+{
+	unsigned long nr_purged_areas = 0;
+	unsigned int nr_purge_helpers;
+	unsigned int nr_purge_nodes;
+	struct vmap_node *vn;
+	int i;
+
+	lockdep_assert_held(&vmap_purge_lock);
+
+	/*
+	 * Use cpumask to mark which node has to be processed.
+	 */
+	purge_nodes = CPU_MASK_NONE;
+
+	for (i = 0; i < nr_vmap_nodes; i++) {
+		vn = &vmap_nodes[i];
+
+		INIT_LIST_HEAD(&vn->purge_list);
+		vn->skip_populate = full_pool_decay;
+		decay_va_pool_node(vn, full_pool_decay);
+
+		if (RB_EMPTY_ROOT(&vn->lazy.root))
+			continue;
+
+		spin_lock(&vn->lazy.lock);
+		WRITE_ONCE(vn->lazy.root.rb_node, NULL);
+		list_replace_init(&vn->lazy.head, &vn->purge_list);
+		spin_unlock(&vn->lazy.lock);
+
+		start = min(start, list_first_entry(&vn->purge_list,
+			struct vmap_area, list)->va_start);
+
+		end = max(end, list_last_entry(&vn->purge_list,
+			struct vmap_area, list)->va_end);
+
+		cpumask_set_cpu(i, &purge_nodes);
+	}
+
+	nr_purge_nodes = cpumask_weight(&purge_nodes);
+	if (nr_purge_nodes > 0) {
+		flush_tlb_kernel_range(start, end);
+
+		/* One extra worker is per a lazy_max_pages() full set minus one. */
+		nr_purge_helpers = atomic_long_read(&vmap_lazy_nr) / lazy_max_pages();
+		nr_purge_helpers = clamp(nr_purge_helpers, 1U, nr_purge_nodes) - 1;
+
+		for_each_cpu(i, &purge_nodes) {
+			vn = &vmap_nodes[i];
+
+			if (nr_purge_helpers > 0) {
+				INIT_WORK(&vn->purge_work, purge_vmap_node);
+
+				if (cpumask_test_cpu(i, cpu_online_mask))
+					schedule_work_on(i, &vn->purge_work);
+				else
+					schedule_work(&vn->purge_work);
+
+				nr_purge_helpers--;
+			} else {
+				vn->purge_work.func = NULL;
+				purge_vmap_node(&vn->purge_work);
+				nr_purged_areas += vn->nr_purged;
+			}
+		}
+
+		for_each_cpu(i, &purge_nodes) {
+			vn = &vmap_nodes[i];
+
+			if (vn->purge_work.func) {
+				flush_work(&vn->purge_work);
+				nr_purged_areas += vn->nr_purged;
+			}
+		}
+	}
+
+	trace_purge_vmap_area_lazy(start, end, nr_purged_areas);
+	return nr_purged_areas > 0;
 }
 
 /*
@@ -1863,22 +2276,15 @@ static void reclaim_and_purge_vmap_areas(void)
 {
 	mutex_lock(&vmap_purge_lock);
 	purge_fragmented_blocks_allcpus();
-	__purge_vmap_area_lazy(ULONG_MAX, 0);
+	__purge_vmap_area_lazy(ULONG_MAX, 0, true);
 	mutex_unlock(&vmap_purge_lock);
 }
 
 static void drain_vmap_area_work(struct work_struct *work)
 {
-	unsigned long nr_lazy;
-
-	do {
-		mutex_lock(&vmap_purge_lock);
-		__purge_vmap_area_lazy(ULONG_MAX, 0);
-		mutex_unlock(&vmap_purge_lock);
-
-		/* Recheck if further work is required. */
-		nr_lazy = atomic_long_read(&vmap_lazy_nr);
-	} while (nr_lazy > lazy_max_pages());
+	mutex_lock(&vmap_purge_lock);
+	__purge_vmap_area_lazy(ULONG_MAX, 0, false);
+	mutex_unlock(&vmap_purge_lock);
 }
 
 /*
@@ -1890,6 +2296,8 @@ static void free_vmap_area_noflush(struct vmap_area *va)
 {
 	unsigned long nr_lazy_max = lazy_max_pages();
 	unsigned long va_start = va->va_start;
+	unsigned int vn_id = decode_vn_id(va->flags);
+	struct vmap_node *vn;
 	unsigned long nr_lazy;
 
 	if (WARN_ON_ONCE(!list_empty(&va->list)))
@@ -1899,12 +2307,15 @@ static void free_vmap_area_noflush(struct vmap_area *va)
 				PAGE_SHIFT, &vmap_lazy_nr);
 
 	/*
-	 * Merge or place it to the purge tree/list.
+	 * If it was request by a certain node we would like to
+	 * return it to that node, i.e. its pool for later reuse.
 	 */
-	spin_lock(&purge_vmap_area_lock);
-	merge_or_add_vmap_area(va,
-		&purge_vmap_area_root, &purge_vmap_area_list);
-	spin_unlock(&purge_vmap_area_lock);
+	vn = is_vn_id_valid(vn_id) ?
+		id_to_node(vn_id):addr_to_node(va->va_start);
+
+	spin_lock(&vn->lazy.lock);
+	insert_vmap_area(va, &vn->lazy.root, &vn->lazy.head);
+	spin_unlock(&vn->lazy.lock);
 
 	trace_free_vmap_area_noflush(va_start, nr_lazy, nr_lazy_max);
 
@@ -1928,26 +2339,62 @@ static void free_unmap_vmap_area(struct vmap_area *va)
 
 struct vmap_area *find_vmap_area(unsigned long addr)
 {
+	struct vmap_node *vn;
 	struct vmap_area *va;
+	int i, j;
 
-	spin_lock(&vmap_area_lock);
-	va = __find_vmap_area(addr, &vmap_area_root);
-	spin_unlock(&vmap_area_lock);
+	/*
+	 * An addr_to_node_id(addr) converts an address to a node index
+	 * where a VA is located. If VA spans several zones and passed
+	 * addr is not the same as va->va_start, what is not common, we
+	 * may need to scan extra nodes. See an example:
+	 *
+	 *      <----va---->
+	 * -|-----|-----|-----|-----|-
+	 *     1     2     0     1
+	 *
+	 * VA resides in node 1 whereas it spans 1, 2 an 0. If passed
+	 * addr is within 2 or 0 nodes we should do extra work.
+	 */
+	i = j = addr_to_node_id(addr);
+	do {
+		vn = &vmap_nodes[i];
 
-	return va;
+		spin_lock(&vn->busy.lock);
+		va = __find_vmap_area(addr, &vn->busy.root);
+		spin_unlock(&vn->busy.lock);
+
+		if (va)
+			return va;
+	} while ((i = (i + 1) % nr_vmap_nodes) != j);
+
+	return NULL;
 }
 
 static struct vmap_area *find_unlink_vmap_area(unsigned long addr)
 {
+	struct vmap_node *vn;
 	struct vmap_area *va;
+	int i, j;
 
-	spin_lock(&vmap_area_lock);
-	va = __find_vmap_area(addr, &vmap_area_root);
-	if (va)
-		unlink_va(va, &vmap_area_root);
-	spin_unlock(&vmap_area_lock);
+	/*
+	 * Check the comment in the find_vmap_area() about the loop.
+	 */
+	i = j = addr_to_node_id(addr);
+	do {
+		vn = &vmap_nodes[i];
 
-	return va;
+		spin_lock(&vn->busy.lock);
+		va = __find_vmap_area(addr, &vn->busy.root);
+		if (va)
+			unlink_va(va, &vn->busy.root);
+		spin_unlock(&vn->busy.lock);
+
+		if (va)
+			return va;
+	} while ((i = (i + 1) % nr_vmap_nodes) != j);
+
+	return NULL;
 }
 
 /*** Per cpu kva allocator ***/
@@ -2149,6 +2596,7 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
 
 static void free_vmap_block(struct vmap_block *vb)
 {
+	struct vmap_node *vn;
 	struct vmap_block *tmp;
 	struct xarray *xa;
 
@@ -2156,9 +2604,10 @@ static void free_vmap_block(struct vmap_block *vb)
 	tmp = xa_erase(xa, addr_to_vb_idx(vb->va->va_start));
 	BUG_ON(tmp != vb);
 
-	spin_lock(&vmap_area_lock);
-	unlink_va(vb->va, &vmap_area_root);
-	spin_unlock(&vmap_area_lock);
+	vn = addr_to_node(vb->va->va_start);
+	spin_lock(&vn->busy.lock);
+	unlink_va(vb->va, &vn->busy.root);
+	spin_unlock(&vn->busy.lock);
 
 	free_vmap_area_noflush(vb->va);
 	kfree_rcu(vb, rcu_head);
@@ -2375,7 +2824,7 @@ static void _vm_unmap_aliases(unsigned long start, unsigned long end, int flush)
 	}
 	free_purged_blocks(&purge_list);
 
-	if (!__purge_vmap_area_lazy(start, end) && flush)
+	if (!__purge_vmap_area_lazy(start, end, false) && flush)
 		flush_tlb_kernel_range(start, end);
 	mutex_unlock(&vmap_purge_lock);
 }
@@ -2569,47 +3018,6 @@ void __init vm_area_register_early(struct vm_struct *vm, size_t align)
 	kasan_populate_early_vm_area_shadow(vm->addr, vm->size);
 }
 
-static void vmap_init_free_space(void)
-{
-	unsigned long vmap_start = 1;
-	const unsigned long vmap_end = ULONG_MAX;
-	struct vmap_area *busy, *free;
-
-	/*
-	 *     B     F     B     B     B     F
-	 * -|-----|.....|-----|-----|-----|.....|-
-	 *  |           The KVA space           |
-	 *  |<--------------------------------->|
-	 */
-	list_for_each_entry(busy, &vmap_area_list, list) {
-		if (busy->va_start - vmap_start > 0) {
-			free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
-			if (!WARN_ON_ONCE(!free)) {
-				free->va_start = vmap_start;
-				free->va_end = busy->va_start;
-
-				insert_vmap_area_augment(free, NULL,
-					&free_vmap_area_root,
-						&free_vmap_area_list);
-			}
-		}
-
-		vmap_start = busy->va_end;
-	}
-
-	if (vmap_end - vmap_start > 0) {
-		free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
-		if (!WARN_ON_ONCE(!free)) {
-			free->va_start = vmap_start;
-			free->va_end = vmap_end;
-
-			insert_vmap_area_augment(free, NULL,
-				&free_vmap_area_root,
-					&free_vmap_area_list);
-		}
-	}
-}
-
 static inline void setup_vmalloc_vm_locked(struct vm_struct *vm,
 	struct vmap_area *va, unsigned long flags, const void *caller)
 {
@@ -2623,9 +3031,11 @@ static inline void setup_vmalloc_vm_locked(struct vm_struct *vm,
 static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
 			      unsigned long flags, const void *caller)
 {
-	spin_lock(&vmap_area_lock);
+	struct vmap_node *vn = addr_to_node(va->va_start);
+
+	spin_lock(&vn->busy.lock);
 	setup_vmalloc_vm_locked(vm, va, flags, caller);
-	spin_unlock(&vmap_area_lock);
+	spin_unlock(&vn->busy.lock);
 }
 
 static void clear_vm_uninitialized_flag(struct vm_struct *vm)
@@ -3813,10 +4223,12 @@ finished:
  */
 long vread_iter(struct iov_iter *iter, const char *addr, size_t count)
 {
+	struct vmap_node *vn;
 	struct vmap_area *va;
 	struct vm_struct *vm;
 	char *vaddr;
 	size_t n, size, flags, remains;
+	unsigned long next;
 
 	addr = kasan_reset_tag(addr);
 
@@ -3826,16 +4238,15 @@ long vread_iter(struct iov_iter *iter, const char *addr, size_t count)
 
 	remains = count;
 
-	spin_lock(&vmap_area_lock);
-	va = find_vmap_area_exceed_addr((unsigned long)addr);
-	if (!va)
+	vn = find_vmap_area_exceed_addr_lock((unsigned long) addr, &va);
+	if (!vn)
 		goto finished_zero;
 
 	/* no intersects with alive vmap_area */
 	if ((unsigned long)addr + remains <= va->va_start)
 		goto finished_zero;
 
-	list_for_each_entry_from(va, &vmap_area_list, list) {
+	do {
 		size_t copied;
 
 		if (remains == 0)
@@ -3850,10 +4261,10 @@ long vread_iter(struct iov_iter *iter, const char *addr, size_t count)
 		WARN_ON(flags == VMAP_BLOCK);
 
 		if (!vm && !flags)
-			continue;
+			goto next_va;
 
 		if (vm && (vm->flags & VM_UNINITIALIZED))
-			continue;
+			goto next_va;
 
 		/* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
 		smp_rmb();
@@ -3862,7 +4273,7 @@ long vread_iter(struct iov_iter *iter, const char *addr, size_t count)
 		size = vm ? get_vm_area_size(vm) : va_size(va);
 
 		if (addr >= vaddr + size)
-			continue;
+			goto next_va;
 
 		if (addr < vaddr) {
 			size_t to_zero = min_t(size_t, vaddr - addr, remains);
@@ -3891,15 +4302,22 @@ long vread_iter(struct iov_iter *iter, const char *addr, size_t count)
 
 		if (copied != n)
 			goto finished;
-	}
+
+	next_va:
+		next = va->va_end;
+		spin_unlock(&vn->busy.lock);
+	} while ((vn = find_vmap_area_exceed_addr_lock(next, &va)));
 
 finished_zero:
-	spin_unlock(&vmap_area_lock);
+	if (vn)
+		spin_unlock(&vn->busy.lock);
+
 	/* zero-fill memory holes */
 	return count - remains + zero_iter(iter, remains);
 finished:
 	/* Nothing remains, or We couldn't copy/zero everything. */
-	spin_unlock(&vmap_area_lock);
+	if (vn)
+		spin_unlock(&vn->busy.lock);
 
 	return count - remains;
 }
@@ -4212,9 +4630,8 @@ retry:
 			/* It is a BUG(), but trigger recovery instead. */
 			goto recovery;
 
-		ret = adjust_va_to_fit_type(&free_vmap_area_root,
-					    &free_vmap_area_list,
-					    va, start, size);
+		ret = va_clip(&free_vmap_area_root,
+			&free_vmap_area_list, va, start, size);
 		if (WARN_ON_ONCE(unlikely(ret)))
 			/* It is a BUG(), but trigger recovery instead. */
 			goto recovery;
@@ -4234,14 +4651,15 @@ retry:
 	}
 
 	/* insert all vm's */
-	spin_lock(&vmap_area_lock);
 	for (area = 0; area < nr_vms; area++) {
-		insert_vmap_area(vas[area], &vmap_area_root, &vmap_area_list);
+		struct vmap_node *vn = addr_to_node(vas[area]->va_start);
 
+		spin_lock(&vn->busy.lock);
+		insert_vmap_area(vas[area], &vn->busy.root, &vn->busy.head);
 		setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC,
 				 pcpu_get_vm_areas);
+		spin_unlock(&vn->busy.lock);
 	}
-	spin_unlock(&vmap_area_lock);
 
 	/*
 	 * Mark allocated areas as accessible. Do it now as a best-effort
@@ -4350,60 +4768,39 @@ void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
 #ifdef CONFIG_PRINTK
 bool vmalloc_dump_obj(void *object)
 {
-	void *objp = (void *)PAGE_ALIGN((unsigned long)object);
 	const void *caller;
 	struct vm_struct *vm;
 	struct vmap_area *va;
+	struct vmap_node *vn;
 	unsigned long addr;
 	unsigned int nr_pages;
 
-	if (!spin_trylock(&vmap_area_lock))
+	addr = PAGE_ALIGN((unsigned long) object);
+	vn = addr_to_node(addr);
+
+	if (!spin_trylock(&vn->busy.lock))
 		return false;
-	va = __find_vmap_area((unsigned long)objp, &vmap_area_root);
-	if (!va) {
-		spin_unlock(&vmap_area_lock);
+
+	va = __find_vmap_area(addr, &vn->busy.root);
+	if (!va || !va->vm) {
+		spin_unlock(&vn->busy.lock);
 		return false;
 	}
 
 	vm = va->vm;
-	if (!vm) {
-		spin_unlock(&vmap_area_lock);
-		return false;
-	}
-	addr = (unsigned long)vm->addr;
+	addr = (unsigned long) vm->addr;
 	caller = vm->caller;
 	nr_pages = vm->nr_pages;
-	spin_unlock(&vmap_area_lock);
+	spin_unlock(&vn->busy.lock);
+
 	pr_cont(" %u-page vmalloc region starting at %#lx allocated at %pS\n",
 		nr_pages, addr, caller);
+
 	return true;
 }
 #endif
 
 #ifdef CONFIG_PROC_FS
-static void *s_start(struct seq_file *m, loff_t *pos)
-	__acquires(&vmap_purge_lock)
-	__acquires(&vmap_area_lock)
-{
-	mutex_lock(&vmap_purge_lock);
-	spin_lock(&vmap_area_lock);
-
-	return seq_list_start(&vmap_area_list, *pos);
-}
-
-static void *s_next(struct seq_file *m, void *p, loff_t *pos)
-{
-	return seq_list_next(p, &vmap_area_list, pos);
-}
-
-static void s_stop(struct seq_file *m, void *p)
-	__releases(&vmap_area_lock)
-	__releases(&vmap_purge_lock)
-{
-	spin_unlock(&vmap_area_lock);
-	mutex_unlock(&vmap_purge_lock);
-}
-
 static void show_numa_info(struct seq_file *m, struct vm_struct *v)
 {
 	if (IS_ENABLED(CONFIG_NUMA)) {
@@ -4430,105 +4827,237 @@ static void show_numa_info(struct seq_file *m, struct vm_struct *v)
 
 static void show_purge_info(struct seq_file *m)
 {
+	struct vmap_node *vn;
 	struct vmap_area *va;
+	int i;
+
+	for (i = 0; i < nr_vmap_nodes; i++) {
+		vn = &vmap_nodes[i];
 
-	spin_lock(&purge_vmap_area_lock);
-	list_for_each_entry(va, &purge_vmap_area_list, list) {
-		seq_printf(m, "0x%pK-0x%pK %7ld unpurged vm_area\n",
-			(void *)va->va_start, (void *)va->va_end,
-			va->va_end - va->va_start);
+		spin_lock(&vn->lazy.lock);
+		list_for_each_entry(va, &vn->lazy.head, list) {
+			seq_printf(m, "0x%pK-0x%pK %7ld unpurged vm_area\n",
+				(void *)va->va_start, (void *)va->va_end,
+				va->va_end - va->va_start);
+		}
+		spin_unlock(&vn->lazy.lock);
 	}
-	spin_unlock(&purge_vmap_area_lock);
 }
 
-static int s_show(struct seq_file *m, void *p)
+static int vmalloc_info_show(struct seq_file *m, void *p)
 {
+	struct vmap_node *vn;
 	struct vmap_area *va;
 	struct vm_struct *v;
+	int i;
 
-	va = list_entry(p, struct vmap_area, list);
+	for (i = 0; i < nr_vmap_nodes; i++) {
+		vn = &vmap_nodes[i];
 
-	if (!va->vm) {
-		if (va->flags & VMAP_RAM)
-			seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n",
-				(void *)va->va_start, (void *)va->va_end,
-				va->va_end - va->va_start);
+		spin_lock(&vn->busy.lock);
+		list_for_each_entry(va, &vn->busy.head, list) {
+			if (!va->vm) {
+				if (va->flags & VMAP_RAM)
+					seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n",
+						(void *)va->va_start, (void *)va->va_end,
+						va->va_end - va->va_start);
 
-		goto final;
-	}
+				continue;
+			}
 
-	v = va->vm;
+			v = va->vm;
 
-	seq_printf(m, "0x%pK-0x%pK %7ld",
-		v->addr, v->addr + v->size, v->size);
+			seq_printf(m, "0x%pK-0x%pK %7ld",
+				v->addr, v->addr + v->size, v->size);
 
-	if (v->caller)
-		seq_printf(m, " %pS", v->caller);
+			if (v->caller)
+				seq_printf(m, " %pS", v->caller);
 
-	if (v->nr_pages)
-		seq_printf(m, " pages=%d", v->nr_pages);
+			if (v->nr_pages)
+				seq_printf(m, " pages=%d", v->nr_pages);
 
-	if (v->phys_addr)
-		seq_printf(m, " phys=%pa", &v->phys_addr);
+			if (v->phys_addr)
+				seq_printf(m, " phys=%pa", &v->phys_addr);
 
-	if (v->flags & VM_IOREMAP)
-		seq_puts(m, " ioremap");
+			if (v->flags & VM_IOREMAP)
+				seq_puts(m, " ioremap");
 
-	if (v->flags & VM_SPARSE)
-		seq_puts(m, " sparse");
+			if (v->flags & VM_SPARSE)
+				seq_puts(m, " sparse");
 
-	if (v->flags & VM_ALLOC)
-		seq_puts(m, " vmalloc");
+			if (v->flags & VM_ALLOC)
+				seq_puts(m, " vmalloc");
 
-	if (v->flags & VM_MAP)
-		seq_puts(m, " vmap");
+			if (v->flags & VM_MAP)
+				seq_puts(m, " vmap");
 
-	if (v->flags & VM_USERMAP)
-		seq_puts(m, " user");
+			if (v->flags & VM_USERMAP)
+				seq_puts(m, " user");
 
-	if (v->flags & VM_DMA_COHERENT)
-		seq_puts(m, " dma-coherent");
+			if (v->flags & VM_DMA_COHERENT)
+				seq_puts(m, " dma-coherent");
 
-	if (is_vmalloc_addr(v->pages))
-		seq_puts(m, " vpages");
+			if (is_vmalloc_addr(v->pages))
+				seq_puts(m, " vpages");
 
-	show_numa_info(m, v);
-	seq_putc(m, '\n');
+			show_numa_info(m, v);
+			seq_putc(m, '\n');
+		}
+		spin_unlock(&vn->busy.lock);
+	}
 
 	/*
 	 * As a final step, dump "unpurged" areas.
 	 */
-final:
-	if (list_is_last(&va->list, &vmap_area_list))
-		show_purge_info(m);
-
+	show_purge_info(m);
 	return 0;
 }
 
-static const struct seq_operations vmalloc_op = {
-	.start = s_start,
-	.next = s_next,
-	.stop = s_stop,
-	.show = s_show,
-};
-
 static int __init proc_vmalloc_init(void)
 {
+	void *priv_data = NULL;
+
 	if (IS_ENABLED(CONFIG_NUMA))
-		proc_create_seq_private("vmallocinfo", 0400, NULL,
-				&vmalloc_op,
-				nr_node_ids * sizeof(unsigned int), NULL);
-	else
-		proc_create_seq("vmallocinfo", 0400, NULL, &vmalloc_op);
+		priv_data = kmalloc(nr_node_ids * sizeof(unsigned int), GFP_KERNEL);
+
+	proc_create_single_data("vmallocinfo",
+		0400, NULL, vmalloc_info_show, priv_data);
+
 	return 0;
 }
 module_init(proc_vmalloc_init);
 
 #endif
 
+static void __init vmap_init_free_space(void)
+{
+	unsigned long vmap_start = 1;
+	const unsigned long vmap_end = ULONG_MAX;
+	struct vmap_area *free;
+	struct vm_struct *busy;
+
+	/*
+	 *     B     F     B     B     B     F
+	 * -|-----|.....|-----|-----|-----|.....|-
+	 *  |           The KVA space           |
+	 *  |<--------------------------------->|
+	 */
+	for (busy = vmlist; busy; busy = busy->next) {
+		if ((unsigned long) busy->addr - vmap_start > 0) {
+			free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
+			if (!WARN_ON_ONCE(!free)) {
+				free->va_start = vmap_start;
+				free->va_end = (unsigned long) busy->addr;
+
+				insert_vmap_area_augment(free, NULL,
+					&free_vmap_area_root,
+						&free_vmap_area_list);
+			}
+		}
+
+		vmap_start = (unsigned long) busy->addr + busy->size;
+	}
+
+	if (vmap_end - vmap_start > 0) {
+		free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
+		if (!WARN_ON_ONCE(!free)) {
+			free->va_start = vmap_start;
+			free->va_end = vmap_end;
+
+			insert_vmap_area_augment(free, NULL,
+				&free_vmap_area_root,
+					&free_vmap_area_list);
+		}
+	}
+}
+
+static void vmap_init_nodes(void)
+{
+	struct vmap_node *vn;
+	int i, n;
+
+#if BITS_PER_LONG == 64
+	/*
+	 * A high threshold of max nodes is fixed and bound to 128,
+	 * thus a scale factor is 1 for systems where number of cores
+	 * are less or equal to specified threshold.
+	 *
+	 * As for NUMA-aware notes. For bigger systems, for example
+	 * NUMA with multi-sockets, where we can end-up with thousands
+	 * of cores in total, a "sub-numa-clustering" should be added.
+	 *
+	 * In this case a NUMA domain is considered as a single entity
+	 * with dedicated sub-nodes in it which describe one group or
+	 * set of cores. Therefore a per-domain purging is supposed to
+	 * be added as well as a per-domain balancing.
+	 */
+	n = clamp_t(unsigned int, num_possible_cpus(), 1, 128);
+
+	if (n > 1) {
+		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT | __GFP_NOWARN);
+		if (vn) {
+			/* Node partition is 16 pages. */
+			vmap_zone_size = (1 << 4) * PAGE_SIZE;
+			nr_vmap_nodes = n;
+			vmap_nodes = vn;
+		} else {
+			pr_err("Failed to allocate an array. Disable a node layer\n");
+		}
+	}
+#endif
+
+	for (n = 0; n < nr_vmap_nodes; n++) {
+		vn = &vmap_nodes[n];
+		vn->busy.root = RB_ROOT;
+		INIT_LIST_HEAD(&vn->busy.head);
+		spin_lock_init(&vn->busy.lock);
+
+		vn->lazy.root = RB_ROOT;
+		INIT_LIST_HEAD(&vn->lazy.head);
+		spin_lock_init(&vn->lazy.lock);
+
+		for (i = 0; i < MAX_VA_SIZE_PAGES; i++) {
+			INIT_LIST_HEAD(&vn->pool[i].head);
+			WRITE_ONCE(vn->pool[i].len, 0);
+		}
+
+		spin_lock_init(&vn->pool_lock);
+	}
+}
+
+static unsigned long
+vmap_node_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+	unsigned long count;
+	struct vmap_node *vn;
+	int i, j;
+
+	for (count = 0, i = 0; i < nr_vmap_nodes; i++) {
+		vn = &vmap_nodes[i];
+
+		for (j = 0; j < MAX_VA_SIZE_PAGES; j++)
+			count += READ_ONCE(vn->pool[j].len);
+	}
+
+	return count ? count : SHRINK_EMPTY;
+}
+
+static unsigned long
+vmap_node_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
+{
+	int i;
+
+	for (i = 0; i < nr_vmap_nodes; i++)
+		decay_va_pool_node(&vmap_nodes[i], true);
+
+	return SHRINK_STOP;
+}
+
 void __init vmalloc_init(void)
 {
+	struct shrinker *vmap_node_shrinker;
 	struct vmap_area *va;
+	struct vmap_node *vn;
 	struct vm_struct *tmp;
 	int i;
 
@@ -4550,6 +5079,11 @@ void __init vmalloc_init(void)
 		xa_init(&vbq->vmap_blocks);
 	}
 
+	/*
+	 * Setup nodes before importing vmlist.
+	 */
+	vmap_init_nodes();
+
 	/* Import existing vmlist entries. */
 	for (tmp = vmlist; tmp; tmp = tmp->next) {
 		va = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
@@ -4559,7 +5093,9 @@ void __init vmalloc_init(void)
 		va->va_start = (unsigned long)tmp->addr;
 		va->va_end = va->va_start + tmp->size;
 		va->vm = tmp;
-		insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
+
+		vn = addr_to_node(va->va_start);
+		insert_vmap_area(va, &vn->busy.root, &vn->busy.head);
 	}
 
 	/*
@@ -4567,4 +5103,14 @@ void __init vmalloc_init(void)
 	 */
 	vmap_init_free_space();
 	vmap_initialized = true;
+
+	vmap_node_shrinker = shrinker_alloc(0, "vmap-node");
+	if (!vmap_node_shrinker) {
+		pr_err("Failed to allocate vmap-node shrinker!\n");
+		return;
+	}
+
+	vmap_node_shrinker->count_objects = vmap_node_shrink_count;
+	vmap_node_shrinker->scan_objects = vmap_node_shrink_scan;
+	shrinker_register(vmap_node_shrinker);
 }