Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax

[platform/kernel/linux-starfive.git] / kernel / memremap.c

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 620fc4d..9eced2c 100644 (file)
--- 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__);
 }
@@ -177,7 +143,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
        struct resource *res = &pgmap->res;
        struct dev_pagemap *conflict_pgmap;
        pgprot_t pgprot = PAGE_KERNEL;
-       unsigned long pgoff, order;
        int error, nid, is_ram;
 
        align_start = res->start & ~(SECTION_SIZE - 1);
@@ -216,20 +181,10 @@ 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)
@@ -274,8 +229,8 @@ 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);
@@ -315,7 +270,7 @@ 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();