memremap: Convert to XArray
Use the new xa_store_range function instead of the radix tree.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 5b8600d..e842fab 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -1,47 +1,21 @@
/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright(c) 2015 Intel Corporation. All rights reserved. */
-#include <linux/radix-tree.h>
#include <linux/device.h>
-#include <linux/types.h>
-#include <linux/pfn_t.h>
#include <linux/io.h>
#include <linux/kasan.h>
-#include <linux/mm.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_MUTEX(pgmap_lock);
-static RADIX_TREE(pgmap_radix, GFP_KERNEL);
+static DEFINE_XARRAY(pgmap_array);
#define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
#define SECTION_SIZE (1UL << PA_SECTION_SHIFT)
-static unsigned long order_at(struct resource *res, unsigned long pgoff)
-{
- unsigned long phys_pgoff = PHYS_PFN(res->start) + pgoff;
- unsigned long nr_pages, mask;
-
- nr_pages = PHYS_PFN(resource_size(res));
- if (nr_pages == pgoff)
- return ULONG_MAX;
-
- /*
- * What is the largest aligned power-of-2 range available from
- * this resource pgoff to the end of the resource range,
- * considering the alignment of the current pgoff?
- */
- mask = phys_pgoff | rounddown_pow_of_two(nr_pages - pgoff);
- if (!mask)
- return ULONG_MAX;
-
- return find_first_bit(&mask, BITS_PER_LONG);
-}
-
-#define foreach_order_pgoff(res, order, pgoff) \
- for (pgoff = 0, order = order_at((res), pgoff); order < ULONG_MAX; \
- pgoff += 1UL << order, order = order_at((res), pgoff))
-
#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)
vm_fault_t device_private_entry_fault(struct vm_area_struct *vma,
unsigned long addr,
@@ -70,18 +44,10 @@ vm_fault_t device_private_entry_fault(struct vm_area_struct *vma,
EXPORT_SYMBOL(device_private_entry_fault);
#endif /* CONFIG_DEVICE_PRIVATE */
-static void pgmap_radix_release(struct resource *res, unsigned long end_pgoff)
+static void pgmap_array_delete(struct resource *res)
{
- unsigned long pgoff, order;
-
- mutex_lock(&pgmap_lock);
- foreach_order_pgoff(res, order, pgoff) {
- if (pgoff >= end_pgoff)
- break;
- radix_tree_delete(&pgmap_radix, PHYS_PFN(res->start) + pgoff);
- }
- mutex_unlock(&pgmap_lock);
-
+ xa_store_range(&pgmap_array, PHYS_PFN(res->start), PHYS_PFN(res->end),
+ NULL, GFP_KERNEL);
synchronize_rcu();
}
@@ -142,7 +108,7 @@ static void devm_memremap_pages_release(void *data)
mem_hotplug_done();
untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
- pgmap_radix_release(res, -1);
+ pgmap_array_delete(res);
dev_WARN_ONCE(dev, pgmap->altmap.alloc,
"%s: failed to free all reserved pages\n", __func__);
}
@@ -175,7 +141,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
struct vmem_altmap *altmap = pgmap->altmap_valid ?
&pgmap->altmap : NULL;
struct resource *res = &pgmap->res;
- unsigned long pfn, pgoff, order;
+ unsigned long pfn;
pgprot_t pgprot = PAGE_KERNEL;
int error, nid, is_ram;
struct dev_pagemap *conflict_pgmap;
@@ -216,20 +182,10 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
pgmap->dev = dev;
- mutex_lock(&pgmap_lock);
- error = 0;
-
- foreach_order_pgoff(res, order, pgoff) {
- error = __radix_tree_insert(&pgmap_radix,
- PHYS_PFN(res->start) + pgoff, order, pgmap);
- if (error) {
- dev_err(dev, "%s: failed: %d\n", __func__, error);
- break;
- }
- }
- mutex_unlock(&pgmap_lock);
+ error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(res->start),
+ PHYS_PFN(res->end), pgmap, GFP_KERNEL));
if (error)
- goto err_radix;
+ goto err_array;
nid = dev_to_node(dev);
if (nid < 0)
@@ -279,8 +235,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
err_kasan:
untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
err_pfn_remap:
- err_radix:
- pgmap_radix_release(res, pgoff);
+ pgmap_array_delete(res);
+ err_array:
return ERR_PTR(error);
}
EXPORT_SYMBOL(devm_memremap_pages);
@@ -320,7 +276,7 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
/* fall back to slow path lookup */
rcu_read_lock();
- pgmap = radix_tree_lookup(&pgmap_radix, PHYS_PFN(phys));
+ pgmap = xa_load(&pgmap_array, PHYS_PFN(phys));
if (pgmap && !percpu_ref_tryget_live(pgmap->ref))
pgmap = NULL;
rcu_read_unlock();