[linux-block.git] / kernel / dma / pool.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2012 ARM Ltd.
 * Copyright (C) 2020 Google LLC
 */
#include <linux/cma.h>
#include <linux/debugfs.h>
#include <linux/dma-map-ops.h>
#include <linux/dma-direct.h>
#include <linux/init.h>
#include <linux/genalloc.h>
#include <linux/set_memory.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

static struct gen_pool *atomic_pool_dma __ro_after_init;
static unsigned long pool_size_dma;
static struct gen_pool *atomic_pool_dma32 __ro_after_init;
static unsigned long pool_size_dma32;
static struct gen_pool *atomic_pool_kernel __ro_after_init;
static unsigned long pool_size_kernel;

/* Size can be defined by the coherent_pool command line */
static size_t atomic_pool_size;

/* Dynamic background expansion when the atomic pool is near capacity */
static struct work_struct atomic_pool_work;

static int __init early_coherent_pool(char *p)
{
	atomic_pool_size = memparse(p, &p);
	return 0;
}
early_param("coherent_pool", early_coherent_pool);

static void __init dma_atomic_pool_debugfs_init(void)
{
	struct dentry *root;

	root = debugfs_create_dir("dma_pools", NULL);
	debugfs_create_ulong("pool_size_dma", 0400, root, &pool_size_dma);
	debugfs_create_ulong("pool_size_dma32", 0400, root, &pool_size_dma32);
	debugfs_create_ulong("pool_size_kernel", 0400, root, &pool_size_kernel);
}

static void dma_atomic_pool_size_add(gfp_t gfp, size_t size)
{
	if (gfp & __GFP_DMA)
		pool_size_dma += size;
	else if (gfp & __GFP_DMA32)
		pool_size_dma32 += size;
	else
		pool_size_kernel += size;
}

static bool cma_in_zone(gfp_t gfp)
{
	unsigned long size;
	phys_addr_t end;
	struct cma *cma;

	cma = dev_get_cma_area(NULL);
	if (!cma)
		return false;

	size = cma_get_size(cma);
	if (!size)
		return false;

	/* CMA can't cross zone boundaries, see cma_activate_area() */
	end = cma_get_base(cma) + size - 1;
	if (IS_ENABLED(CONFIG_ZONE_DMA) && (gfp & GFP_DMA))
		return end <= DMA_BIT_MASK(zone_dma_bits);
	if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32))
		return end <= DMA_BIT_MASK(32);
	return true;
}

static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size,
			      gfp_t gfp)
{
	unsigned int order;
	struct page *page = NULL;
	void *addr;
	int ret = -ENOMEM;

	/* Cannot allocate larger than MAX_ORDER-1 */
	order = min(get_order(pool_size), MAX_ORDER-1);

	do {
		pool_size = 1 << (PAGE_SHIFT + order);
		if (cma_in_zone(gfp))
			page = dma_alloc_from_contiguous(NULL, 1 << order,
							 order, false);
		if (!page)
			page = alloc_pages(gfp, order);
	} while (!page && order-- > 0);
	if (!page)
		goto out;

	arch_dma_prep_coherent(page, pool_size);

#ifdef CONFIG_DMA_DIRECT_REMAP
	addr = dma_common_contiguous_remap(page, pool_size,
					   pgprot_dmacoherent(PAGE_KERNEL),
					   __builtin_return_address(0));
	if (!addr)
		goto free_page;
#else
	addr = page_to_virt(page);
#endif
	/*
	 * Memory in the atomic DMA pools must be unencrypted, the pools do not
	 * shrink so no re-encryption occurs in dma_direct_free().
	 */
	ret = set_memory_decrypted((unsigned long)page_to_virt(page),
				   1 << order);
	if (ret)
		goto remove_mapping;
	ret = gen_pool_add_virt(pool, (unsigned long)addr, page_to_phys(page),
				pool_size, NUMA_NO_NODE);
	if (ret)
		goto encrypt_mapping;

	dma_atomic_pool_size_add(gfp, pool_size);
	return 0;

encrypt_mapping:
	ret = set_memory_encrypted((unsigned long)page_to_virt(page),
				   1 << order);
	if (WARN_ON_ONCE(ret)) {
		/* Decrypt succeeded but encrypt failed, purposely leak */
		goto out;
	}
remove_mapping:
#ifdef CONFIG_DMA_DIRECT_REMAP
	dma_common_free_remap(addr, pool_size);
#endif
free_page: __maybe_unused
	__free_pages(page, order);
out:
	return ret;
}

static void atomic_pool_resize(struct gen_pool *pool, gfp_t gfp)
{
	if (pool && gen_pool_avail(pool) < atomic_pool_size)
		atomic_pool_expand(pool, gen_pool_size(pool), gfp);
}

static void atomic_pool_work_fn(struct work_struct *work)
{
	if (IS_ENABLED(CONFIG_ZONE_DMA))
		atomic_pool_resize(atomic_pool_dma,
				   GFP_KERNEL | GFP_DMA);
	if (IS_ENABLED(CONFIG_ZONE_DMA32))
		atomic_pool_resize(atomic_pool_dma32,
				   GFP_KERNEL | GFP_DMA32);
	atomic_pool_resize(atomic_pool_kernel, GFP_KERNEL);
}

static __init struct gen_pool *__dma_atomic_pool_init(size_t pool_size,
						      gfp_t gfp)
{
	struct gen_pool *pool;
	int ret;

	pool = gen_pool_create(PAGE_SHIFT, NUMA_NO_NODE);
	if (!pool)
		return NULL;

	gen_pool_set_algo(pool, gen_pool_first_fit_order_align, NULL);

	ret = atomic_pool_expand(pool, pool_size, gfp);
	if (ret) {
		gen_pool_destroy(pool);
		pr_err("DMA: failed to allocate %zu KiB %pGg pool for atomic allocation\n",
		       pool_size >> 10, &gfp);
		return NULL;
	}

	pr_info("DMA: preallocated %zu KiB %pGg pool for atomic allocations\n",
		gen_pool_size(pool) >> 10, &gfp);
	return pool;
}

static int __init dma_atomic_pool_init(void)
{
	int ret = 0;

	/*
	 * If coherent_pool was not used on the command line, default the pool
	 * sizes to 128KB per 1GB of memory, min 128KB, max MAX_ORDER-1.
	 */
	if (!atomic_pool_size) {
		unsigned long pages = totalram_pages() / (SZ_1G / SZ_128K);
		pages = min_t(unsigned long, pages, MAX_ORDER_NR_PAGES);
		atomic_pool_size = max_t(size_t, pages << PAGE_SHIFT, SZ_128K);
	}
	INIT_WORK(&atomic_pool_work, atomic_pool_work_fn);

	atomic_pool_kernel = __dma_atomic_pool_init(atomic_pool_size,
						    GFP_KERNEL);
	if (!atomic_pool_kernel)
		ret = -ENOMEM;
	if (has_managed_dma()) {
		atomic_pool_dma = __dma_atomic_pool_init(atomic_pool_size,
						GFP_KERNEL | GFP_DMA);
		if (!atomic_pool_dma)
			ret = -ENOMEM;
	}
	if (IS_ENABLED(CONFIG_ZONE_DMA32)) {
		atomic_pool_dma32 = __dma_atomic_pool_init(atomic_pool_size,
						GFP_KERNEL | GFP_DMA32);
		if (!atomic_pool_dma32)
			ret = -ENOMEM;
	}

	dma_atomic_pool_debugfs_init();
	return ret;
}
postcore_initcall(dma_atomic_pool_init);

static inline struct gen_pool *dma_guess_pool(struct gen_pool *prev, gfp_t gfp)
{
	if (prev == NULL) {
		if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32))
			return atomic_pool_dma32;
		if (atomic_pool_dma && (gfp & GFP_DMA))
			return atomic_pool_dma;
		return atomic_pool_kernel;
	}
	if (prev == atomic_pool_kernel)
		return atomic_pool_dma32 ? atomic_pool_dma32 : atomic_pool_dma;
	if (prev == atomic_pool_dma32)
		return atomic_pool_dma;
	return NULL;
}

static struct page *__dma_alloc_from_pool(struct device *dev, size_t size,
		struct gen_pool *pool, void **cpu_addr,
		bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t))
{
	unsigned long addr;
	phys_addr_t phys;

	addr = gen_pool_alloc(pool, size);
	if (!addr)
		return NULL;

	phys = gen_pool_virt_to_phys(pool, addr);
	if (phys_addr_ok && !phys_addr_ok(dev, phys, size)) {
		gen_pool_free(pool, addr, size);
		return NULL;
	}

	if (gen_pool_avail(pool) < atomic_pool_size)
		schedule_work(&atomic_pool_work);

	*cpu_addr = (void *)addr;
	memset(*cpu_addr, 0, size);
	return pfn_to_page(__phys_to_pfn(phys));
}

struct page *dma_alloc_from_pool(struct device *dev, size_t size,
		void **cpu_addr, gfp_t gfp,
		bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t))
{
	struct gen_pool *pool = NULL;
	struct page *page;

	while ((pool = dma_guess_pool(pool, gfp))) {
		page = __dma_alloc_from_pool(dev, size, pool, cpu_addr,
					     phys_addr_ok);
		if (page)
			return page;
	}

	WARN(1, "Failed to get suitable pool for %s\n", dev_name(dev));
	return NULL;
}

bool dma_free_from_pool(struct device *dev, void *start, size_t size)
{
	struct gen_pool *pool = NULL;

	while ((pool = dma_guess_pool(pool, 0))) {
		if (!gen_pool_has_addr(pool, (unsigned long)start, size))
			continue;
		gen_pool_free(pool, (unsigned long)start, size);
		return true;
	}

	return false;
}
Commit	Line	Data
e860c299 DR	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* Copyright (C) 2012 ARM Ltd.
	4	* Copyright (C) 2020 Google LLC
	5	*/
d7e673ec	6	#include <linux/cma.h>
2edc5bb3	7	#include <linux/debugfs.h>
0b1abd1f	8	#include <linux/dma-map-ops.h>
e860c299	9	#include <linux/dma-direct.h>
e860c299 DR	10	#include <linux/init.h>
e860c299 DR	11	#include <linux/genalloc.h>
76a19940	12	#include <linux/set_memory.h>
e860c299	13	#include <linux/slab.h>
54adadf9	14	#include <linux/workqueue.h>
e860c299	15
c84dc6e6	16	static struct gen_pool *atomic_pool_dma __ro_after_init;
2edc5bb3	17	static unsigned long pool_size_dma;
c84dc6e6	18	static struct gen_pool *atomic_pool_dma32 __ro_after_init;
2edc5bb3	19	static unsigned long pool_size_dma32;
c84dc6e6	20	static struct gen_pool *atomic_pool_kernel __ro_after_init;
2edc5bb3	21	static unsigned long pool_size_kernel;
e860c299	22
1d659236 DR	23	/* Size can be defined by the coherent_pool command line */
1d659236 DR	24	static size_t atomic_pool_size;
54adadf9 DR	25
	26	/* Dynamic background expansion when the atomic pool is near capacity */
	27	static struct work_struct atomic_pool_work;
e860c299 DR	28
	29	static int __init early_coherent_pool(char *p)
	30	{
	31	atomic_pool_size = memparse(p, &p);
	32	return 0;
	33	}
	34	early_param("coherent_pool", early_coherent_pool);
	35
2edc5bb3 DR	36	static void __init dma_atomic_pool_debugfs_init(void)
	37	{
	38	struct dentry *root;
	39
	40	root = debugfs_create_dir("dma_pools", NULL);
2edc5bb3 DR	41	debugfs_create_ulong("pool_size_dma", 0400, root, &pool_size_dma);
	42	debugfs_create_ulong("pool_size_dma32", 0400, root, &pool_size_dma32);
	43	debugfs_create_ulong("pool_size_kernel", 0400, root, &pool_size_kernel);
	44	}
	45
	46	static void dma_atomic_pool_size_add(gfp_t gfp, size_t size)
	47	{
	48	if (gfp & __GFP_DMA)
	49	pool_size_dma += size;
	50	else if (gfp & __GFP_DMA32)
	51	pool_size_dma32 += size;
	52	else
	53	pool_size_kernel += size;
	54	}
	55
d7e673ec NSJ	56	static bool cma_in_zone(gfp_t gfp)
	57	{
	58	unsigned long size;
	59	phys_addr_t end;
	60	struct cma *cma;
	61
	62	cma = dev_get_cma_area(NULL);
	63	if (!cma)
	64	return false;
	65
	66	size = cma_get_size(cma);
	67	if (!size)
	68	return false;
	69
	70	/* CMA can't cross zone boundaries, see cma_activate_area() */
	71	end = cma_get_base(cma) + size - 1;
	72	if (IS_ENABLED(CONFIG_ZONE_DMA) && (gfp & GFP_DMA))
	73	return end <= DMA_BIT_MASK(zone_dma_bits);
	74	if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32))
	75	return end <= DMA_BIT_MASK(32);
	76	return true;
	77	}
	78
54adadf9 DR	79	static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size,
54adadf9 DR	80	gfp_t gfp)
e860c299	81	{
54adadf9	82	unsigned int order;
892fc9f6	83	struct page *page = NULL;
e860c299	84	void *addr;
54adadf9 DR	85	int ret = -ENOMEM;
	86
	87	/* Cannot allocate larger than MAX_ORDER-1 */
	88	order = min(get_order(pool_size), MAX_ORDER-1);
	89
	90	do {
	91	pool_size = 1 << (PAGE_SHIFT + order);
d7e673ec NSJ	92	if (cma_in_zone(gfp))
	93	page = dma_alloc_from_contiguous(NULL, 1 << order,
	94	order, false);
	95	if (!page)
	96	page = alloc_pages(gfp, order);
54adadf9	97	} while (!page && order-- > 0);
e860c299 DR	98	if (!page)
	99	goto out;
	100
c84dc6e6	101	arch_dma_prep_coherent(page, pool_size);
e860c299	102
76a19940	103	#ifdef CONFIG_DMA_DIRECT_REMAP
c84dc6e6	104	addr = dma_common_contiguous_remap(page, pool_size,
e860c299 DR	105	pgprot_dmacoherent(PAGE_KERNEL),
	106	__builtin_return_address(0));
	107	if (!addr)
54adadf9	108	goto free_page;
76a19940 DR	109	#else
	110	addr = page_to_virt(page);
	111	#endif
	112	/*
	113	* Memory in the atomic DMA pools must be unencrypted, the pools do not
2f5388a2	114	* shrink so no re-encryption occurs in dma_direct_free().
76a19940 DR	115	*/
	116	ret = set_memory_decrypted((unsigned long)page_to_virt(page),
	117	1 << order);
	118	if (ret)
	119	goto remove_mapping;
54adadf9 DR	120	ret = gen_pool_add_virt(pool, (unsigned long)addr, page_to_phys(page),
54adadf9 DR	121	pool_size, NUMA_NO_NODE);
e860c299	122	if (ret)
76a19940	123	goto encrypt_mapping;
e860c299	124
2edc5bb3	125	dma_atomic_pool_size_add(gfp, pool_size);
e860c299 DR	126	return 0;
e860c299 DR	127
76a19940 DR	128	encrypt_mapping:
	129	ret = set_memory_encrypted((unsigned long)page_to_virt(page),
	130	1 << order);
	131	if (WARN_ON_ONCE(ret)) {
	132	/* Decrypt succeeded but encrypt failed, purposely leak */
	133	goto out;
	134	}
e860c299	135	remove_mapping:
76a19940	136	#ifdef CONFIG_DMA_DIRECT_REMAP
c84dc6e6	137	dma_common_free_remap(addr, pool_size);
76a19940 DR	138	#endif
76a19940 DR	139	free_page: __maybe_unused
d9765e41	140	__free_pages(page, order);
e860c299	141	out:
54adadf9 DR	142	return ret;
	143	}
	144
	145	static void atomic_pool_resize(struct gen_pool *pool, gfp_t gfp)
	146	{
	147	if (pool && gen_pool_avail(pool) < atomic_pool_size)
	148	atomic_pool_expand(pool, gen_pool_size(pool), gfp);
	149	}
	150
	151	static void atomic_pool_work_fn(struct work_struct *work)
	152	{
	153	if (IS_ENABLED(CONFIG_ZONE_DMA))
	154	atomic_pool_resize(atomic_pool_dma,
	155	GFP_KERNEL \| GFP_DMA);
	156	if (IS_ENABLED(CONFIG_ZONE_DMA32))
	157	atomic_pool_resize(atomic_pool_dma32,
	158	GFP_KERNEL \| GFP_DMA32);
	159	atomic_pool_resize(atomic_pool_kernel, GFP_KERNEL);
	160	}
	161
	162	static __init struct gen_pool *__dma_atomic_pool_init(size_t pool_size,
	163	gfp_t gfp)
	164	{
	165	struct gen_pool *pool;
	166	int ret;
	167
	168	pool = gen_pool_create(PAGE_SHIFT, NUMA_NO_NODE);
	169	if (!pool)
	170	return NULL;
	171
	172	gen_pool_set_algo(pool, gen_pool_first_fit_order_align, NULL);
	173
	174	ret = atomic_pool_expand(pool, pool_size, gfp);
	175	if (ret) {
	176	gen_pool_destroy(pool);
	177	pr_err("DMA: failed to allocate %zu KiB %pGg pool for atomic allocation\n",
	178	pool_size >> 10, &gfp);
	179	return NULL;
	180	}
	181
	182	pr_info("DMA: preallocated %zu KiB %pGg pool for atomic allocations\n",
	183	gen_pool_size(pool) >> 10, &gfp);
	184	return pool;
e860c299	185	}
c84dc6e6 DR	186
	187	static int __init dma_atomic_pool_init(void)
	188	{
	189	int ret = 0;
c84dc6e6	190
1d659236 DR	191	/*
	192	* If coherent_pool was not used on the command line, default the pool
	193	* sizes to 128KB per 1GB of memory, min 128KB, max MAX_ORDER-1.
	194	*/
	195	if (!atomic_pool_size) {
3ee06a6d GU	196	unsigned long pages = totalram_pages() / (SZ_1G / SZ_128K);
	197	pages = min_t(unsigned long, pages, MAX_ORDER_NR_PAGES);
	198	atomic_pool_size = max_t(size_t, pages << PAGE_SHIFT, SZ_128K);
1d659236	199	}
54adadf9 DR	200	INIT_WORK(&atomic_pool_work, atomic_pool_work_fn);
	201
	202	atomic_pool_kernel = __dma_atomic_pool_init(atomic_pool_size,
	203	GFP_KERNEL);
	204	if (!atomic_pool_kernel)
	205	ret = -ENOMEM;
a674e48c	206	if (has_managed_dma()) {
54adadf9 DR	207	atomic_pool_dma = __dma_atomic_pool_init(atomic_pool_size,
	208	GFP_KERNEL \| GFP_DMA);
	209	if (!atomic_pool_dma)
	210	ret = -ENOMEM;
c84dc6e6 DR	211	}
c84dc6e6 DR	212	if (IS_ENABLED(CONFIG_ZONE_DMA32)) {
54adadf9 DR	213	atomic_pool_dma32 = __dma_atomic_pool_init(atomic_pool_size,
	214	GFP_KERNEL \| GFP_DMA32);
	215	if (!atomic_pool_dma32)
	216	ret = -ENOMEM;
c84dc6e6	217	}
2edc5bb3 DR	218
2edc5bb3 DR	219	dma_atomic_pool_debugfs_init();
c84dc6e6 DR	220	return ret;
c84dc6e6 DR	221	}
e860c299 DR	222	postcore_initcall(dma_atomic_pool_init);
e860c299 DR	223
9420139f	224	static inline struct gen_pool dma_guess_pool(struct gen_pool prev, gfp_t gfp)
e860c299	225	{
9420139f CH	226	if (prev == NULL) {
	227	if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32))
	228	return atomic_pool_dma32;
a674e48c	229	if (atomic_pool_dma && (gfp & GFP_DMA))
9420139f CH	230	return atomic_pool_dma;
	231	return atomic_pool_kernel;
	232	}
	233	if (prev == atomic_pool_kernel)
	234	return atomic_pool_dma32 ? atomic_pool_dma32 : atomic_pool_dma;
	235	if (prev == atomic_pool_dma32)
c84dc6e6	236	return atomic_pool_dma;
9420139f	237	return NULL;
c84dc6e6	238	}
e860c299	239
9420139f CH	240	static struct page __dma_alloc_from_pool(struct device dev, size_t size,
	241	struct gen_pool pool, void *cpu_addr,
	242	bool (phys_addr_ok)(struct device , phys_addr_t, size_t))
48b67038	243	{
9420139f CH	244	unsigned long addr;
9420139f CH	245	phys_addr_t phys;
48b67038	246
9420139f CH	247	addr = gen_pool_alloc(pool, size);
	248	if (!addr)
	249	return NULL;
48b67038	250
9420139f CH	251	phys = gen_pool_virt_to_phys(pool, addr);
	252	if (phys_addr_ok && !phys_addr_ok(dev, phys, size)) {
	253	gen_pool_free(pool, addr, size);
	254	return NULL;
	255	}
48b67038	256
9420139f CH	257	if (gen_pool_avail(pool) < atomic_pool_size)
9420139f CH	258	schedule_work(&atomic_pool_work);
48b67038	259
9420139f CH	260	cpu_addr = (void )addr;
	261	memset(*cpu_addr, 0, size);
	262	return pfn_to_page(__phys_to_pfn(phys));
48b67038 NSJ	263	}
48b67038 NSJ	264
9420139f CH	265	struct page dma_alloc_from_pool(struct device dev, size_t size,
	266	void **cpu_addr, gfp_t gfp,
	267	bool (phys_addr_ok)(struct device , phys_addr_t, size_t))
e860c299	268	{
81e9d894	269	struct gen_pool *pool = NULL;
9420139f	270	struct page *page;
81e9d894	271
9420139f CH	272	while ((pool = dma_guess_pool(pool, gfp))) {
	273	page = __dma_alloc_from_pool(dev, size, pool, cpu_addr,
	274	phys_addr_ok);
	275	if (page)
	276	return page;
e860c299 DR	277	}
e860c299 DR	278
9420139f CH	279	WARN(1, "Failed to get suitable pool for %s\n", dev_name(dev));
9420139f CH	280	return NULL;
e860c299 DR	281	}
e860c299 DR	282
c84dc6e6	283	bool dma_free_from_pool(struct device dev, void start, size_t size)
e860c299	284	{
81e9d894	285	struct gen_pool *pool = NULL;
c84dc6e6	286
9420139f CH	287	while ((pool = dma_guess_pool(pool, 0))) {
	288	if (!gen_pool_has_addr(pool, (unsigned long)start, size))
	289	continue;
	290	gen_pool_free(pool, (unsigned long)start, size);
	291	return true;
81e9d894	292	}
9420139f CH	293
9420139f CH	294	return false;
e860c299	295	}