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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright 2006-2008, Michael Ellerman, IBM Corporation.
 
 
 
 
 
 
  4 */
  5
  6#include <linux/slab.h>
  7#include <linux/kernel.h>
  8#include <linux/kmemleak.h>
  9#include <linux/bitmap.h>
 10#include <linux/memblock.h>
 11#include <linux/of.h>
 12#include <asm/msi_bitmap.h>
 13#include <asm/setup.h>
 14
 15int msi_bitmap_alloc_hwirqs(struct msi_bitmap *bmp, int num)
 16{
 17	unsigned long flags;
 18	int offset, order = get_count_order(num);
 19
 20	spin_lock_irqsave(&bmp->lock, flags);
 21
 22	offset = bitmap_find_next_zero_area(bmp->bitmap, bmp->irq_count, 0,
 23					    num, (1 << order) - 1);
 24	if (offset > bmp->irq_count)
 25		goto err;
 26
 27	bitmap_set(bmp->bitmap, offset, num);
 28	spin_unlock_irqrestore(&bmp->lock, flags);
 29
 30	pr_debug("msi_bitmap: allocated 0x%x at offset 0x%x\n", num, offset);
 31
 32	return offset;
 33err:
 34	spin_unlock_irqrestore(&bmp->lock, flags);
 35	return -ENOMEM;
 36}
 37EXPORT_SYMBOL(msi_bitmap_alloc_hwirqs);
 38
 39void msi_bitmap_free_hwirqs(struct msi_bitmap *bmp, unsigned int offset,
 40			    unsigned int num)
 41{
 42	unsigned long flags;
 43
 44	pr_debug("msi_bitmap: freeing 0x%x at offset 0x%x\n",
 45		 num, offset);
 46
 47	spin_lock_irqsave(&bmp->lock, flags);
 48	bitmap_clear(bmp->bitmap, offset, num);
 49	spin_unlock_irqrestore(&bmp->lock, flags);
 50}
 51EXPORT_SYMBOL(msi_bitmap_free_hwirqs);
 52
 53void msi_bitmap_reserve_hwirq(struct msi_bitmap *bmp, unsigned int hwirq)
 54{
 55	unsigned long flags;
 56
 57	pr_debug("msi_bitmap: reserving hwirq 0x%x\n", hwirq);
 58
 59	spin_lock_irqsave(&bmp->lock, flags);
 60	bitmap_allocate_region(bmp->bitmap, hwirq, 0);
 61	spin_unlock_irqrestore(&bmp->lock, flags);
 62}
 63
 64/**
 65 * msi_bitmap_reserve_dt_hwirqs - Reserve irqs specified in the device tree.
 66 * @bmp: pointer to the MSI bitmap.
 67 *
 68 * Looks in the device tree to see if there is a property specifying which
 69 * irqs can be used for MSI. If found those irqs reserved in the device tree
 70 * are reserved in the bitmap.
 71 *
 72 * Returns 0 for success, < 0 if there was an error, and > 0 if no property
 73 * was found in the device tree.
 74 **/
 75int msi_bitmap_reserve_dt_hwirqs(struct msi_bitmap *bmp)
 76{
 77	int i, j, len;
 78	const u32 *p;
 79
 80	if (!bmp->of_node)
 81		return 1;
 82
 83	p = of_get_property(bmp->of_node, "msi-available-ranges", &len);
 84	if (!p) {
 85		pr_debug("msi_bitmap: no msi-available-ranges property " \
 86			 "found on %pOF\n", bmp->of_node);
 87		return 1;
 88	}
 89
 90	if (len % (2 * sizeof(u32)) != 0) {
 91		printk(KERN_WARNING "msi_bitmap: Malformed msi-available-ranges"
 92		       " property on %pOF\n", bmp->of_node);
 93		return -EINVAL;
 94	}
 95
 96	bitmap_allocate_region(bmp->bitmap, 0, get_count_order(bmp->irq_count));
 97
 98	spin_lock(&bmp->lock);
 99
100	/* Format is: (<u32 start> <u32 count>)+ */
101	len /= 2 * sizeof(u32);
102	for (i = 0; i < len; i++, p += 2) {
103		for (j = 0; j < *(p + 1); j++)
104			bitmap_release_region(bmp->bitmap, *p + j, 0);
105	}
106
107	spin_unlock(&bmp->lock);
108
109	return 0;
110}
111
112int __ref msi_bitmap_alloc(struct msi_bitmap *bmp, unsigned int irq_count,
113		     struct device_node *of_node)
114{
115	int size;
116
117	if (!irq_count)
118		return -EINVAL;
119
120	size = BITS_TO_LONGS(irq_count) * sizeof(long);
121	pr_debug("msi_bitmap: allocator bitmap size is 0x%x bytes\n", size);
122
123	bmp->bitmap_from_slab = slab_is_available();
124	if (bmp->bitmap_from_slab)
125		bmp->bitmap = kzalloc(size, GFP_KERNEL);
126	else {
127		bmp->bitmap = memblock_alloc(size, SMP_CACHE_BYTES);
128		if (!bmp->bitmap)
129			panic("%s: Failed to allocate %u bytes\n", __func__,
130			      size);
131		/* the bitmap won't be freed from memblock allocator */
132		kmemleak_not_leak(bmp->bitmap);
133	}
134
135	if (!bmp->bitmap) {
136		pr_debug("msi_bitmap: ENOMEM allocating allocator bitmap!\n");
137		return -ENOMEM;
138	}
139
140	/* We zalloc'ed the bitmap, so all irqs are free by default */
141	spin_lock_init(&bmp->lock);
142	bmp->of_node = of_node_get(of_node);
143	bmp->irq_count = irq_count;
144
145	return 0;
146}
147
148void msi_bitmap_free(struct msi_bitmap *bmp)
149{
150	if (bmp->bitmap_from_slab)
151		kfree(bmp->bitmap);
152	of_node_put(bmp->of_node);
153	bmp->bitmap = NULL;
154}
155
156#ifdef CONFIG_MSI_BITMAP_SELFTEST
157
158static void __init test_basics(void)
159{
160	struct msi_bitmap bmp;
161	int rc, i, size = 512;
162
163	/* Can't allocate a bitmap of 0 irqs */
164	WARN_ON(msi_bitmap_alloc(&bmp, 0, NULL) == 0);
165
166	/* of_node may be NULL */
167	WARN_ON(msi_bitmap_alloc(&bmp, size, NULL));
168
169	/* Should all be free by default */
170	WARN_ON(bitmap_find_free_region(bmp.bitmap, size, get_count_order(size)));
171	bitmap_release_region(bmp.bitmap, 0, get_count_order(size));
172
173	/* With no node, there's no msi-available-ranges, so expect > 0 */
174	WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp) <= 0);
175
176	/* Should all still be free */
177	WARN_ON(bitmap_find_free_region(bmp.bitmap, size, get_count_order(size)));
178	bitmap_release_region(bmp.bitmap, 0, get_count_order(size));
179
180	/* Check we can fill it up and then no more */
181	for (i = 0; i < size; i++)
182		WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) < 0);
183
184	WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) >= 0);
185
186	/* Should all be allocated */
187	WARN_ON(bitmap_find_free_region(bmp.bitmap, size, 0) >= 0);
188
189	/* And if we free one we can then allocate another */
190	msi_bitmap_free_hwirqs(&bmp, size / 2, 1);
191	WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) != size / 2);
192
193	/* Free most of them for the alignment tests */
194	msi_bitmap_free_hwirqs(&bmp, 3, size - 3);
195
196	/* Check we get a naturally aligned offset */
197	rc = msi_bitmap_alloc_hwirqs(&bmp, 2);
198	WARN_ON(rc < 0 && rc % 2 != 0);
199	rc = msi_bitmap_alloc_hwirqs(&bmp, 4);
200	WARN_ON(rc < 0 && rc % 4 != 0);
201	rc = msi_bitmap_alloc_hwirqs(&bmp, 8);
202	WARN_ON(rc < 0 && rc % 8 != 0);
203	rc = msi_bitmap_alloc_hwirqs(&bmp, 9);
204	WARN_ON(rc < 0 && rc % 16 != 0);
205	rc = msi_bitmap_alloc_hwirqs(&bmp, 3);
206	WARN_ON(rc < 0 && rc % 4 != 0);
207	rc = msi_bitmap_alloc_hwirqs(&bmp, 7);
208	WARN_ON(rc < 0 && rc % 8 != 0);
209	rc = msi_bitmap_alloc_hwirqs(&bmp, 121);
210	WARN_ON(rc < 0 && rc % 128 != 0);
211
212	msi_bitmap_free(&bmp);
213
214	/* Clients may WARN_ON bitmap == NULL for "not-allocated" */
215	WARN_ON(bmp.bitmap != NULL);
216}
217
218static void __init test_of_node(void)
219{
220	u32 prop_data[] = { 10, 10, 25, 3, 40, 1, 100, 100, 200, 20 };
221	const char *expected_str = "0-9,20-24,28-39,41-99,220-255";
222	char *prop_name = "msi-available-ranges";
223	char *node_name = "/fakenode";
224	struct device_node of_node;
225	struct property prop;
226	struct msi_bitmap bmp;
227#define SIZE_EXPECTED 256
228	DECLARE_BITMAP(expected, SIZE_EXPECTED);
229
230	/* There should really be a struct device_node allocator */
231	memset(&of_node, 0, sizeof(of_node));
232	of_node_init(&of_node);
233	of_node.full_name = node_name;
234
235	WARN_ON(msi_bitmap_alloc(&bmp, SIZE_EXPECTED, &of_node));
236
237	/* No msi-available-ranges, so expect > 0 */
238	WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp) <= 0);
239
240	/* Should all still be free */
241	WARN_ON(bitmap_find_free_region(bmp.bitmap, SIZE_EXPECTED,
242					get_count_order(SIZE_EXPECTED)));
243	bitmap_release_region(bmp.bitmap, 0, get_count_order(SIZE_EXPECTED));
244
245	/* Now create a fake msi-available-ranges property */
246
247	/* There should really .. oh whatever */
248	memset(&prop, 0, sizeof(prop));
249	prop.name = prop_name;
250	prop.value = &prop_data;
251	prop.length = sizeof(prop_data);
252
253	of_node.properties = &prop;
254
255	/* msi-available-ranges, so expect == 0 */
256	WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp));
257
258	/* Check we got the expected result */
259	WARN_ON(bitmap_parselist(expected_str, expected, SIZE_EXPECTED));
260	WARN_ON(!bitmap_equal(expected, bmp.bitmap, SIZE_EXPECTED));
261
262	msi_bitmap_free(&bmp);
263	kfree(bmp.bitmap);
264}
265
266static int __init msi_bitmap_selftest(void)
267{
268	printk(KERN_DEBUG "Running MSI bitmap self-tests ...\n");
269
270	test_basics();
271	test_of_node();
272
273	return 0;
274}
275late_initcall(msi_bitmap_selftest);
276#endif /* CONFIG_MSI_BITMAP_SELFTEST */
v4.6
 
  1/*
  2 * Copyright 2006-2008, Michael Ellerman, IBM Corporation.
  3 *
  4 * This program is free software; you can redistribute it and/or
  5 * modify it under the terms of the GNU General Public License
  6 * as published by the Free Software Foundation; version 2 of the
  7 * License.
  8 *
  9 */
 10
 11#include <linux/slab.h>
 12#include <linux/kernel.h>
 
 13#include <linux/bitmap.h>
 14#include <linux/bootmem.h>
 
 15#include <asm/msi_bitmap.h>
 16#include <asm/setup.h>
 17
 18int msi_bitmap_alloc_hwirqs(struct msi_bitmap *bmp, int num)
 19{
 20	unsigned long flags;
 21	int offset, order = get_count_order(num);
 22
 23	spin_lock_irqsave(&bmp->lock, flags);
 24
 25	offset = bitmap_find_next_zero_area(bmp->bitmap, bmp->irq_count, 0,
 26					    num, (1 << order) - 1);
 27	if (offset > bmp->irq_count)
 28		goto err;
 29
 30	bitmap_set(bmp->bitmap, offset, num);
 31	spin_unlock_irqrestore(&bmp->lock, flags);
 32
 33	pr_debug("msi_bitmap: allocated 0x%x at offset 0x%x\n", num, offset);
 34
 35	return offset;
 36err:
 37	spin_unlock_irqrestore(&bmp->lock, flags);
 38	return -ENOMEM;
 39}
 40EXPORT_SYMBOL(msi_bitmap_alloc_hwirqs);
 41
 42void msi_bitmap_free_hwirqs(struct msi_bitmap *bmp, unsigned int offset,
 43			    unsigned int num)
 44{
 45	unsigned long flags;
 46
 47	pr_debug("msi_bitmap: freeing 0x%x at offset 0x%x\n",
 48		 num, offset);
 49
 50	spin_lock_irqsave(&bmp->lock, flags);
 51	bitmap_clear(bmp->bitmap, offset, num);
 52	spin_unlock_irqrestore(&bmp->lock, flags);
 53}
 54EXPORT_SYMBOL(msi_bitmap_free_hwirqs);
 55
 56void msi_bitmap_reserve_hwirq(struct msi_bitmap *bmp, unsigned int hwirq)
 57{
 58	unsigned long flags;
 59
 60	pr_debug("msi_bitmap: reserving hwirq 0x%x\n", hwirq);
 61
 62	spin_lock_irqsave(&bmp->lock, flags);
 63	bitmap_allocate_region(bmp->bitmap, hwirq, 0);
 64	spin_unlock_irqrestore(&bmp->lock, flags);
 65}
 66
 67/**
 68 * msi_bitmap_reserve_dt_hwirqs - Reserve irqs specified in the device tree.
 69 * @bmp: pointer to the MSI bitmap.
 70 *
 71 * Looks in the device tree to see if there is a property specifying which
 72 * irqs can be used for MSI. If found those irqs reserved in the device tree
 73 * are reserved in the bitmap.
 74 *
 75 * Returns 0 for success, < 0 if there was an error, and > 0 if no property
 76 * was found in the device tree.
 77 **/
 78int msi_bitmap_reserve_dt_hwirqs(struct msi_bitmap *bmp)
 79{
 80	int i, j, len;
 81	const u32 *p;
 82
 83	if (!bmp->of_node)
 84		return 1;
 85
 86	p = of_get_property(bmp->of_node, "msi-available-ranges", &len);
 87	if (!p) {
 88		pr_debug("msi_bitmap: no msi-available-ranges property " \
 89			 "found on %s\n", bmp->of_node->full_name);
 90		return 1;
 91	}
 92
 93	if (len % (2 * sizeof(u32)) != 0) {
 94		printk(KERN_WARNING "msi_bitmap: Malformed msi-available-ranges"
 95		       " property on %s\n", bmp->of_node->full_name);
 96		return -EINVAL;
 97	}
 98
 99	bitmap_allocate_region(bmp->bitmap, 0, get_count_order(bmp->irq_count));
100
101	spin_lock(&bmp->lock);
102
103	/* Format is: (<u32 start> <u32 count>)+ */
104	len /= 2 * sizeof(u32);
105	for (i = 0; i < len; i++, p += 2) {
106		for (j = 0; j < *(p + 1); j++)
107			bitmap_release_region(bmp->bitmap, *p + j, 0);
108	}
109
110	spin_unlock(&bmp->lock);
111
112	return 0;
113}
114
115int __init_refok msi_bitmap_alloc(struct msi_bitmap *bmp, unsigned int irq_count,
116		     struct device_node *of_node)
117{
118	int size;
119
120	if (!irq_count)
121		return -EINVAL;
122
123	size = BITS_TO_LONGS(irq_count) * sizeof(long);
124	pr_debug("msi_bitmap: allocator bitmap size is 0x%x bytes\n", size);
125
126	bmp->bitmap_from_slab = slab_is_available();
127	if (bmp->bitmap_from_slab)
128		bmp->bitmap = kzalloc(size, GFP_KERNEL);
129	else {
130		bmp->bitmap = memblock_virt_alloc(size, 0);
 
 
 
131		/* the bitmap won't be freed from memblock allocator */
132		kmemleak_not_leak(bmp->bitmap);
133	}
134
135	if (!bmp->bitmap) {
136		pr_debug("msi_bitmap: ENOMEM allocating allocator bitmap!\n");
137		return -ENOMEM;
138	}
139
140	/* We zalloc'ed the bitmap, so all irqs are free by default */
141	spin_lock_init(&bmp->lock);
142	bmp->of_node = of_node_get(of_node);
143	bmp->irq_count = irq_count;
144
145	return 0;
146}
147
148void msi_bitmap_free(struct msi_bitmap *bmp)
149{
150	if (bmp->bitmap_from_slab)
151		kfree(bmp->bitmap);
152	of_node_put(bmp->of_node);
153	bmp->bitmap = NULL;
154}
155
156#ifdef CONFIG_MSI_BITMAP_SELFTEST
157
158static void __init test_basics(void)
159{
160	struct msi_bitmap bmp;
161	int rc, i, size = 512;
162
163	/* Can't allocate a bitmap of 0 irqs */
164	WARN_ON(msi_bitmap_alloc(&bmp, 0, NULL) == 0);
165
166	/* of_node may be NULL */
167	WARN_ON(msi_bitmap_alloc(&bmp, size, NULL));
168
169	/* Should all be free by default */
170	WARN_ON(bitmap_find_free_region(bmp.bitmap, size, get_count_order(size)));
171	bitmap_release_region(bmp.bitmap, 0, get_count_order(size));
172
173	/* With no node, there's no msi-available-ranges, so expect > 0 */
174	WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp) <= 0);
175
176	/* Should all still be free */
177	WARN_ON(bitmap_find_free_region(bmp.bitmap, size, get_count_order(size)));
178	bitmap_release_region(bmp.bitmap, 0, get_count_order(size));
179
180	/* Check we can fill it up and then no more */
181	for (i = 0; i < size; i++)
182		WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) < 0);
183
184	WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) >= 0);
185
186	/* Should all be allocated */
187	WARN_ON(bitmap_find_free_region(bmp.bitmap, size, 0) >= 0);
188
189	/* And if we free one we can then allocate another */
190	msi_bitmap_free_hwirqs(&bmp, size / 2, 1);
191	WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) != size / 2);
192
193	/* Free most of them for the alignment tests */
194	msi_bitmap_free_hwirqs(&bmp, 3, size - 3);
195
196	/* Check we get a naturally aligned offset */
197	rc = msi_bitmap_alloc_hwirqs(&bmp, 2);
198	WARN_ON(rc < 0 && rc % 2 != 0);
199	rc = msi_bitmap_alloc_hwirqs(&bmp, 4);
200	WARN_ON(rc < 0 && rc % 4 != 0);
201	rc = msi_bitmap_alloc_hwirqs(&bmp, 8);
202	WARN_ON(rc < 0 && rc % 8 != 0);
203	rc = msi_bitmap_alloc_hwirqs(&bmp, 9);
204	WARN_ON(rc < 0 && rc % 16 != 0);
205	rc = msi_bitmap_alloc_hwirqs(&bmp, 3);
206	WARN_ON(rc < 0 && rc % 4 != 0);
207	rc = msi_bitmap_alloc_hwirqs(&bmp, 7);
208	WARN_ON(rc < 0 && rc % 8 != 0);
209	rc = msi_bitmap_alloc_hwirqs(&bmp, 121);
210	WARN_ON(rc < 0 && rc % 128 != 0);
211
212	msi_bitmap_free(&bmp);
213
214	/* Clients may WARN_ON bitmap == NULL for "not-allocated" */
215	WARN_ON(bmp.bitmap != NULL);
216}
217
218static void __init test_of_node(void)
219{
220	u32 prop_data[] = { 10, 10, 25, 3, 40, 1, 100, 100, 200, 20 };
221	const char *expected_str = "0-9,20-24,28-39,41-99,220-255";
222	char *prop_name = "msi-available-ranges";
223	char *node_name = "/fakenode";
224	struct device_node of_node;
225	struct property prop;
226	struct msi_bitmap bmp;
227	int size = 256;
228	DECLARE_BITMAP(expected, size);
229
230	/* There should really be a struct device_node allocator */
231	memset(&of_node, 0, sizeof(of_node));
232	of_node_init(&of_node);
233	of_node.full_name = node_name;
234
235	WARN_ON(msi_bitmap_alloc(&bmp, size, &of_node));
236
237	/* No msi-available-ranges, so expect > 0 */
238	WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp) <= 0);
239
240	/* Should all still be free */
241	WARN_ON(bitmap_find_free_region(bmp.bitmap, size, get_count_order(size)));
242	bitmap_release_region(bmp.bitmap, 0, get_count_order(size));
 
243
244	/* Now create a fake msi-available-ranges property */
245
246	/* There should really .. oh whatever */
247	memset(&prop, 0, sizeof(prop));
248	prop.name = prop_name;
249	prop.value = &prop_data;
250	prop.length = sizeof(prop_data);
251
252	of_node.properties = &prop;
253
254	/* msi-available-ranges, so expect == 0 */
255	WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp));
256
257	/* Check we got the expected result */
258	WARN_ON(bitmap_parselist(expected_str, expected, size));
259	WARN_ON(!bitmap_equal(expected, bmp.bitmap, size));
260
261	msi_bitmap_free(&bmp);
262	kfree(bmp.bitmap);
263}
264
265static int __init msi_bitmap_selftest(void)
266{
267	printk(KERN_DEBUG "Running MSI bitmap self-tests ...\n");
268
269	test_basics();
270	test_of_node();
271
272	return 0;
273}
274late_initcall(msi_bitmap_selftest);
275#endif /* CONFIG_MSI_BITMAP_SELFTEST */