Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) /* SPDX-License-Identifier: GPL-2.0 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /* Copyright(c) 2015 Intel Corporation. All rights reserved. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5) #include <linux/kasan.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) #include <linux/memory_hotplug.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) #include <linux/mm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/pfn_t.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/swap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/mmzone.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/swapops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/wait_bit.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/xarray.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) static DEFINE_XARRAY(pgmap_array);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19)  * The memremap() and memremap_pages() interfaces are alternately used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20)  * to map persistent memory namespaces. These interfaces place different
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21)  * constraints on the alignment and size of the mapping (namespace).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22)  * memremap() can map individual PAGE_SIZE pages. memremap_pages() can
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23)  * only map subsections (2MB), and at least one architecture (PowerPC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24)  * the minimum mapping granularity of memremap_pages() is 16MB.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26)  * The role of memremap_compat_align() is to communicate the minimum
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27)  * arch supported alignment of a namespace such that it can freely
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28)  * switch modes without violating the arch constraint. Namely, do not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29)  * allow a namespace to be PAGE_SIZE aligned since that namespace may be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30)  * reconfigured into a mode that requires SUBSECTION_SIZE alignment.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) #ifndef CONFIG_ARCH_HAS_MEMREMAP_COMPAT_ALIGN
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) unsigned long memremap_compat_align(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	return SUBSECTION_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) EXPORT_SYMBOL_GPL(memremap_compat_align);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) #ifdef CONFIG_DEV_PAGEMAP_OPS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) EXPORT_SYMBOL(devmap_managed_key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) static void devmap_managed_enable_put(struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	if (pgmap->type == MEMORY_DEVICE_PRIVATE ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	    pgmap->type == MEMORY_DEVICE_FS_DAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 		static_branch_dec(&devmap_managed_key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) static void devmap_managed_enable_get(struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	if (pgmap->type == MEMORY_DEVICE_PRIVATE ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	    pgmap->type == MEMORY_DEVICE_FS_DAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 		static_branch_inc(&devmap_managed_key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) static void devmap_managed_enable_get(struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) static void devmap_managed_enable_put(struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) #endif /* CONFIG_DEV_PAGEMAP_OPS */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) static void pgmap_array_delete(struct range *range)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 	xa_store_range(&pgmap_array, PHYS_PFN(range->start), PHYS_PFN(range->end),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 			NULL, GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	synchronize_rcu();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) static unsigned long pfn_first(struct dev_pagemap *pgmap, int range_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	struct range *range = &pgmap->ranges[range_id];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	unsigned long pfn = PHYS_PFN(range->start);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 	if (range_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 		return pfn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	return pfn + vmem_altmap_offset(pgmap_altmap(pgmap));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) bool pgmap_pfn_valid(struct dev_pagemap *pgmap, unsigned long pfn)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	for (i = 0; i < pgmap->nr_range; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 		struct range *range = &pgmap->ranges[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 		if (pfn >= PHYS_PFN(range->start) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 		    pfn <= PHYS_PFN(range->end))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 			return pfn >= pfn_first(pgmap, i);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) static unsigned long pfn_end(struct dev_pagemap *pgmap, int range_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	const struct range *range = &pgmap->ranges[range_id];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	return (range->start + range_len(range)) >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) static unsigned long pfn_next(unsigned long pfn)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	if (pfn % 1024 == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 		cond_resched();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	return pfn + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) #define for_each_device_pfn(pfn, map, i) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	for (pfn = pfn_first(map, i); pfn < pfn_end(map, i); pfn = pfn_next(pfn))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) static void dev_pagemap_kill(struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	if (pgmap->ops && pgmap->ops->kill)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 		pgmap->ops->kill(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 		percpu_ref_kill(pgmap->ref);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) static void dev_pagemap_cleanup(struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	if (pgmap->ops && pgmap->ops->cleanup) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 		pgmap->ops->cleanup(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 		wait_for_completion(&pgmap->done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 		percpu_ref_exit(pgmap->ref);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	 * Undo the pgmap ref assignment for the internal case as the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	 * caller may re-enable the same pgmap.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	if (pgmap->ref == &pgmap->internal_ref)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 		pgmap->ref = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) static void pageunmap_range(struct dev_pagemap *pgmap, int range_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	struct range *range = &pgmap->ranges[range_id];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	struct page *first_page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	int nid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	/* make sure to access a memmap that was actually initialized */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	first_page = pfn_to_page(pfn_first(pgmap, range_id));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	/* pages are dead and unused, undo the arch mapping */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	nid = page_to_nid(first_page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	mem_hotplug_begin();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(range->start),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 				   PHYS_PFN(range_len(range)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 		__remove_pages(PHYS_PFN(range->start),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 			       PHYS_PFN(range_len(range)), NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 		arch_remove_memory(nid, range->start, range_len(range),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 				pgmap_altmap(pgmap));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 		kasan_remove_zero_shadow(__va(range->start), range_len(range));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	mem_hotplug_done();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	pgmap_array_delete(range);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) void memunmap_pages(struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	unsigned long pfn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	dev_pagemap_kill(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 	for (i = 0; i < pgmap->nr_range; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		for_each_device_pfn(pfn, pgmap, i)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 			put_page(pfn_to_page(pfn));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	dev_pagemap_cleanup(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	for (i = 0; i < pgmap->nr_range; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 		pageunmap_range(pgmap, i);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 	WARN_ONCE(pgmap->altmap.alloc, "failed to free all reserved pages\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	devmap_managed_enable_put(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) EXPORT_SYMBOL_GPL(memunmap_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) static void devm_memremap_pages_release(void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	memunmap_pages(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) static void dev_pagemap_percpu_release(struct percpu_ref *ref)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	struct dev_pagemap *pgmap =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 		container_of(ref, struct dev_pagemap, internal_ref);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	complete(&pgmap->done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) static int pagemap_range(struct dev_pagemap *pgmap, struct mhp_params *params,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 		int range_id, int nid)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 	struct range *range = &pgmap->ranges[range_id];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 	struct dev_pagemap *conflict_pgmap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 	int error, is_ram;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 	if (WARN_ONCE(pgmap_altmap(pgmap) && range_id > 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 				"altmap not supported for multiple ranges\n"))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 	conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->start), NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 	if (conflict_pgmap) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 		WARN(1, "Conflicting mapping in same section\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 		put_dev_pagemap(conflict_pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 	conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->end), NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 	if (conflict_pgmap) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 		WARN(1, "Conflicting mapping in same section\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 		put_dev_pagemap(conflict_pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 	is_ram = region_intersects(range->start, range_len(range),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 		IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 	if (is_ram != REGION_DISJOINT) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 		WARN_ONCE(1, "attempted on %s region %#llx-%#llx\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 				is_ram == REGION_MIXED ? "mixed" : "ram",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 				range->start, range->end);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 		return -ENXIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 	error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(range->start),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 				PHYS_PFN(range->end), pgmap, GFP_KERNEL));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 	if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 		return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 	if (nid < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 		nid = numa_mem_id();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 	error = track_pfn_remap(NULL, &params->pgprot, PHYS_PFN(range->start), 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 			range_len(range));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 	if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 		goto err_pfn_remap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 	mem_hotplug_begin();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 	 * For device private memory we call add_pages() as we only need to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 	 * allocate and initialize struct page for the device memory. More-
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 	 * over the device memory is un-accessible thus we do not want to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 	 * create a linear mapping for the memory like arch_add_memory()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) 	 * would do.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) 	 * For all other device memory types, which are accessible by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 	 * the CPU, we do want the linear mapping and thus use
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) 	 * arch_add_memory().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 	if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 		error = add_pages(nid, PHYS_PFN(range->start),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 				PHYS_PFN(range_len(range)), params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 		error = kasan_add_zero_shadow(__va(range->start), range_len(range));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 		if (error) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 			mem_hotplug_done();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 			goto err_kasan;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 		error = arch_add_memory(nid, range->start, range_len(range),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 					params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 	if (!error) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) 		struct zone *zone;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 		zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 		move_pfn_range_to_zone(zone, PHYS_PFN(range->start),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 				PHYS_PFN(range_len(range)), params->altmap,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) 				MIGRATE_MOVABLE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) 	mem_hotplug_done();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 	if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 		goto err_add_memory;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 	 * Initialization of the pages has been deferred until now in order
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 	 * to allow us to do the work while not holding the hotplug lock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 	memmap_init_zone_device(&NODE_DATA(nid)->node_zones[ZONE_DEVICE],
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 				PHYS_PFN(range->start),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 				PHYS_PFN(range_len(range)), pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) 	percpu_ref_get_many(pgmap->ref, pfn_end(pgmap, range_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) 			- pfn_first(pgmap, range_id));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) err_add_memory:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) 	kasan_remove_zero_shadow(__va(range->start), range_len(range));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) err_kasan:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) 	untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) err_pfn_remap:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) 	pgmap_array_delete(range);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 	return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)  * Not device managed version of dev_memremap_pages, undone by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311)  * memunmap_pages().  Please use dev_memremap_pages if you have a struct
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312)  * device available.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) void *memremap_pages(struct dev_pagemap *pgmap, int nid)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 	struct mhp_params params = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) 		.altmap = pgmap_altmap(pgmap),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 		.pgprot = PAGE_KERNEL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) 	};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) 	const int nr_range = pgmap->nr_range;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 	int error, i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 	if (WARN_ONCE(!nr_range, "nr_range must be specified\n"))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 		return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 	switch (pgmap->type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 	case MEMORY_DEVICE_PRIVATE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) 		if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 			WARN(1, "Device private memory not supported\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) 			return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) 		if (!pgmap->ops || !pgmap->ops->migrate_to_ram) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) 			WARN(1, "Missing migrate_to_ram method\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) 			return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) 		if (!pgmap->ops->page_free) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) 			WARN(1, "Missing page_free method\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) 			return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) 		if (!pgmap->owner) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) 			WARN(1, "Missing owner\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) 			return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) 	case MEMORY_DEVICE_FS_DAX:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) 		if (!IS_ENABLED(CONFIG_ZONE_DEVICE) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) 		    IS_ENABLED(CONFIG_FS_DAX_LIMITED)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) 			WARN(1, "File system DAX not supported\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) 			return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) 	case MEMORY_DEVICE_GENERIC:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) 	case MEMORY_DEVICE_PCI_P2PDMA:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) 		params.pgprot = pgprot_noncached(params.pgprot);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) 	default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) 		WARN(1, "Invalid pgmap type %d\n", pgmap->type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) 	if (!pgmap->ref) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) 		if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) 			return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) 		init_completion(&pgmap->done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) 		error = percpu_ref_init(&pgmap->internal_ref,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) 				dev_pagemap_percpu_release, 0, GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) 		if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) 			return ERR_PTR(error);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) 		pgmap->ref = &pgmap->internal_ref;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) 		if (!pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) 			WARN(1, "Missing reference count teardown definition\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) 			return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) 	devmap_managed_enable_get(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) 	 * Clear the pgmap nr_range as it will be incremented for each
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) 	 * successfully processed range. This communicates how many
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) 	 * regions to unwind in the abort case.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) 	pgmap->nr_range = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) 	error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) 	for (i = 0; i < nr_range; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) 		error = pagemap_range(pgmap, &params, i, nid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) 		if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) 		pgmap->nr_range++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) 	if (i < nr_range) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) 		memunmap_pages(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) 		pgmap->nr_range = nr_range;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) 		return ERR_PTR(error);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) 	return __va(pgmap->ranges[0].start);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) EXPORT_SYMBOL_GPL(memremap_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406)  * devm_memremap_pages - remap and provide memmap backing for the given resource
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407)  * @dev: hosting device for @res
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408)  * @pgmap: pointer to a struct dev_pagemap
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410)  * Notes:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411)  * 1/ At a minimum the res and type members of @pgmap must be initialized
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412)  *    by the caller before passing it to this function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414)  * 2/ The altmap field may optionally be initialized, in which case
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415)  *    PGMAP_ALTMAP_VALID must be set in pgmap->flags.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417)  * 3/ The ref field may optionally be provided, in which pgmap->ref must be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418)  *    'live' on entry and will be killed and reaped at
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419)  *    devm_memremap_pages_release() time, or if this routine fails.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421)  * 4/ range is expected to be a host memory range that could feasibly be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422)  *    treated as a "System RAM" range, i.e. not a device mmio range, but
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423)  *    this is not enforced.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) 	int error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) 	void *ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) 	ret = memremap_pages(pgmap, dev_to_node(dev));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) 	if (IS_ERR(ret))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) 		return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) 	error = devm_add_action_or_reset(dev, devm_memremap_pages_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) 			pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) 	if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) 		return ERR_PTR(error);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) EXPORT_SYMBOL_GPL(devm_memremap_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) void devm_memunmap_pages(struct device *dev, struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) 	devm_release_action(dev, devm_memremap_pages_release, pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) EXPORT_SYMBOL_GPL(devm_memunmap_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) unsigned long vmem_altmap_offset(struct vmem_altmap *altmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) 	/* number of pfns from base where pfn_to_page() is valid */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) 	if (altmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) 		return altmap->reserve + altmap->free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) 	altmap->alloc -= nr_pfns;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462)  * get_dev_pagemap() - take a new live reference on the dev_pagemap for @pfn
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463)  * @pfn: page frame number to lookup page_map
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464)  * @pgmap: optional known pgmap that already has a reference
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466)  * If @pgmap is non-NULL and covers @pfn it will be returned as-is.  If @pgmap
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467)  * is non-NULL but does not cover @pfn the reference to it will be released.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) 		struct dev_pagemap *pgmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) 	resource_size_t phys = PFN_PHYS(pfn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) 	 * In the cached case we're already holding a live reference.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) 	if (pgmap) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) 		if (phys >= pgmap->range.start && phys <= pgmap->range.end)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) 			return pgmap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) 		put_dev_pagemap(pgmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) 	/* fall back to slow path lookup */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) 	rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) 	pgmap = xa_load(&pgmap_array, PHYS_PFN(phys));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) 	if (pgmap && !percpu_ref_tryget_live(pgmap->ref))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) 		pgmap = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) 	rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) 	return pgmap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) EXPORT_SYMBOL_GPL(get_dev_pagemap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) #ifdef CONFIG_DEV_PAGEMAP_OPS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) void free_devmap_managed_page(struct page *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) 	/* notify page idle for dax */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) 	if (!is_device_private_page(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) 		wake_up_var(&page->_refcount);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) 	__ClearPageWaiters(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) 	mem_cgroup_uncharge(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) 	 * When a device_private page is freed, the page->mapping field
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) 	 * may still contain a (stale) mapping value. For example, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) 	 * lower bits of page->mapping may still identify the page as an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) 	 * anonymous page. Ultimately, this entire field is just stale
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) 	 * and wrong, and it will cause errors if not cleared.  One
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) 	 * example is:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) 	 *  migrate_vma_pages()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) 	 *    migrate_vma_insert_page()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) 	 *      page_add_new_anon_rmap()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) 	 *        __page_set_anon_rmap()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) 	 *          ...checks page->mapping, via PageAnon(page) call,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) 	 *            and incorrectly concludes that the page is an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) 	 *            anonymous page. Therefore, it incorrectly,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) 	 *            silently fails to set up the new anon rmap.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) 	 * For other types of ZONE_DEVICE pages, migration is either
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) 	 * handled differently or not done at all, so there is no need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) 	 * to clear page->mapping.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) 	page->mapping = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) 	page->pgmap->ops->page_free(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) #endif /* CONFIG_DEV_PAGEMAP_OPS */