-/*
- * Copyright(c) 2015 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
+/* 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/memory_hotplug.h>
#include <linux/swap.h>
#include <linux/swapops.h>
+#include <linux/wait_bit.h>
-#ifndef ioremap_cache
-/* temporary while we convert existing ioremap_cache users to memremap */
-__weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size)
-{
- return ioremap(offset, size);
-}
-#endif
-
-#ifndef arch_memremap_wb
-static void *arch_memremap_wb(resource_size_t offset, unsigned long size)
-{
- return (__force void *)ioremap_cache(offset, size);
-}
-#endif
-
-#ifndef arch_memremap_can_ram_remap
-static bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
- unsigned long flags)
-{
- return true;
-}
-#endif
-
-static void *try_ram_remap(resource_size_t offset, size_t size,
- unsigned long flags)
-{
- unsigned long pfn = PHYS_PFN(offset);
-
- /* In the simple case just return the existing linear address */
- if (pfn_valid(pfn) && !PageHighMem(pfn_to_page(pfn)) &&
- arch_memremap_can_ram_remap(offset, size, flags))
- return __va(offset);
-
- return NULL; /* fallback to arch_memremap_wb */
-}
-
-/**
- * memremap() - remap an iomem_resource as cacheable memory
- * @offset: iomem resource start address
- * @size: size of remap
- * @flags: any of MEMREMAP_WB, MEMREMAP_WT, MEMREMAP_WC,
- * MEMREMAP_ENC, MEMREMAP_DEC
- *
- * memremap() is "ioremap" for cases where it is known that the resource
- * being mapped does not have i/o side effects and the __iomem
- * annotation is not applicable. In the case of multiple flags, the different
- * mapping types will be attempted in the order listed below until one of
- * them succeeds.
- *
- * MEMREMAP_WB - matches the default mapping for System RAM on
- * the architecture. This is usually a read-allocate write-back cache.
- * Morever, if MEMREMAP_WB is specified and the requested remap region is RAM
- * memremap() will bypass establishing a new mapping and instead return
- * a pointer into the direct map.
- *
- * MEMREMAP_WT - establish a mapping whereby writes either bypass the
- * cache or are written through to memory and never exist in a
- * cache-dirty state with respect to program visibility. Attempts to
- * map System RAM with this mapping type will fail.
- *
- * MEMREMAP_WC - establish a writecombine mapping, whereby writes may
- * be coalesced together (e.g. in the CPU's write buffers), but is otherwise
- * uncached. Attempts to map System RAM with this mapping type will fail.
- */
-void *memremap(resource_size_t offset, size_t size, unsigned long flags)
-{
- int is_ram = region_intersects(offset, size,
- IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
- void *addr = NULL;
-
- if (!flags)
- return NULL;
-
- if (is_ram == REGION_MIXED) {
- WARN_ONCE(1, "memremap attempted on mixed range %pa size: %#lx\n",
- &offset, (unsigned long) size);
- return NULL;
- }
-
- /* Try all mapping types requested until one returns non-NULL */
- if (flags & MEMREMAP_WB) {
- /*
- * MEMREMAP_WB is special in that it can be satisifed
- * from the direct map. Some archs depend on the
- * capability of memremap() to autodetect cases where
- * the requested range is potentially in System RAM.
- */
- if (is_ram == REGION_INTERSECTS)
- addr = try_ram_remap(offset, size, flags);
- if (!addr)
- addr = arch_memremap_wb(offset, size);
- }
-
- /*
- * If we don't have a mapping yet and other request flags are
- * present then we will be attempting to establish a new virtual
- * address mapping. Enforce that this mapping is not aliasing
- * System RAM.
- */
- if (!addr && is_ram == REGION_INTERSECTS && flags != MEMREMAP_WB) {
- WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
- &offset, (unsigned long) size);
- return NULL;
- }
-
- if (!addr && (flags & MEMREMAP_WT))
- addr = ioremap_wt(offset, size);
-
- if (!addr && (flags & MEMREMAP_WC))
- addr = ioremap_wc(offset, size);
-
- return addr;
-}
-EXPORT_SYMBOL(memremap);
-
-void memunmap(void *addr)
-{
- if (is_vmalloc_addr(addr))
- iounmap((void __iomem *) addr);
-}
-EXPORT_SYMBOL(memunmap);
-
-static void devm_memremap_release(struct device *dev, void *res)
-{
- memunmap(*(void **)res);
-}
-
-static int devm_memremap_match(struct device *dev, void *res, void *match_data)
-{
- return *(void **)res == match_data;
-}
-
-void *devm_memremap(struct device *dev, resource_size_t offset,
- size_t size, unsigned long flags)
-{
- void **ptr, *addr;
-
- ptr = devres_alloc_node(devm_memremap_release, sizeof(*ptr), GFP_KERNEL,
- dev_to_node(dev));
- if (!ptr)
- return ERR_PTR(-ENOMEM);
-
- addr = memremap(offset, size, flags);
- if (addr) {
- *ptr = addr;
- devres_add(dev, ptr);
- } else {
- devres_free(ptr);
- return ERR_PTR(-ENXIO);
- }
-
- return addr;
-}
-EXPORT_SYMBOL(devm_memremap);
-
-void devm_memunmap(struct device *dev, void *addr)
-{
- WARN_ON(devres_release(dev, devm_memremap_release,
- devm_memremap_match, addr));
-}
-EXPORT_SYMBOL(devm_memunmap);
-
-#ifdef CONFIG_ZONE_DEVICE
static DEFINE_MUTEX(pgmap_lock);
static RADIX_TREE(pgmap_radix, GFP_KERNEL);
#define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
return pgmap;
}
-#endif /* CONFIG_ZONE_DEVICE */
+EXPORT_SYMBOL_GPL(get_dev_pagemap);
+
+#ifdef CONFIG_DEV_PAGEMAP_OPS
+DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
+EXPORT_SYMBOL_GPL(devmap_managed_key);
+static atomic_t devmap_enable;
+
+/*
+ * Toggle the static key for ->page_free() callbacks when dev_pagemap
+ * pages go idle.
+ */
+void dev_pagemap_get_ops(void)
+{
+ if (atomic_inc_return(&devmap_enable) == 1)
+ static_branch_enable(&devmap_managed_key);
+}
+EXPORT_SYMBOL_GPL(dev_pagemap_get_ops);
+
+void dev_pagemap_put_ops(void)
+{
+ if (atomic_dec_and_test(&devmap_enable))
+ static_branch_disable(&devmap_managed_key);
+}
+EXPORT_SYMBOL_GPL(dev_pagemap_put_ops);
-#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC)
-void put_zone_device_private_or_public_page(struct page *page)
+void __put_devmap_managed_page(struct page *page)
{
int count = page_ref_dec_return(page);
} else if (!count)
__put_page(page);
}
-EXPORT_SYMBOL(put_zone_device_private_or_public_page);
-#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
+EXPORT_SYMBOL_GPL(__put_devmap_managed_page);
+#endif /* CONFIG_DEV_PAGEMAP_OPS */
projects / mirror_ubuntu-jammy-kernel.git / blobdiff