Sasha Levin | 28b24c1 | 2015-04-14 15:44:57 -0700 | [diff] [blame] | 1 | /* |
| 2 | * CMA DebugFS Interface |
| 3 | * |
| 4 | * Copyright (c) 2015 Sasha Levin <sasha.levin@oracle.com> |
| 5 | */ |
| 6 | |
| 7 | |
| 8 | #include <linux/debugfs.h> |
| 9 | #include <linux/cma.h> |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 10 | #include <linux/list.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/slab.h> |
Sasha Levin | 8325330 | 2015-04-14 15:45:02 -0700 | [diff] [blame] | 13 | #include <linux/mm_types.h> |
Sasha Levin | 28b24c1 | 2015-04-14 15:44:57 -0700 | [diff] [blame] | 14 | |
| 15 | #include "cma.h" |
| 16 | |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 17 | struct cma_mem { |
| 18 | struct hlist_node node; |
| 19 | struct page *p; |
| 20 | unsigned long n; |
| 21 | }; |
| 22 | |
Sasha Levin | 28b24c1 | 2015-04-14 15:44:57 -0700 | [diff] [blame] | 23 | static struct dentry *cma_debugfs_root; |
| 24 | |
| 25 | static int cma_debugfs_get(void *data, u64 *val) |
| 26 | { |
| 27 | unsigned long *p = data; |
| 28 | |
| 29 | *val = *p; |
| 30 | |
| 31 | return 0; |
| 32 | } |
Sasha Levin | 28b24c1 | 2015-04-14 15:44:57 -0700 | [diff] [blame] | 33 | DEFINE_SIMPLE_ATTRIBUTE(cma_debugfs_fops, cma_debugfs_get, NULL, "%llu\n"); |
| 34 | |
Dmitry Safonov | 2e32b94 | 2015-04-15 16:14:59 -0700 | [diff] [blame] | 35 | static int cma_used_get(void *data, u64 *val) |
| 36 | { |
| 37 | struct cma *cma = data; |
| 38 | unsigned long used; |
| 39 | |
| 40 | mutex_lock(&cma->lock); |
| 41 | /* pages counter is smaller than sizeof(int) */ |
| 42 | used = bitmap_weight(cma->bitmap, (int)cma->count); |
| 43 | mutex_unlock(&cma->lock); |
| 44 | *val = (u64)used << cma->order_per_bit; |
| 45 | |
| 46 | return 0; |
| 47 | } |
Dmitry Safonov | 2e32b94 | 2015-04-15 16:14:59 -0700 | [diff] [blame] | 48 | DEFINE_SIMPLE_ATTRIBUTE(cma_used_fops, cma_used_get, NULL, "%llu\n"); |
| 49 | |
| 50 | static int cma_maxchunk_get(void *data, u64 *val) |
| 51 | { |
| 52 | struct cma *cma = data; |
| 53 | unsigned long maxchunk = 0; |
| 54 | unsigned long start, end = 0; |
| 55 | |
| 56 | mutex_lock(&cma->lock); |
| 57 | for (;;) { |
| 58 | start = find_next_zero_bit(cma->bitmap, cma->count, end); |
| 59 | if (start >= cma->count) |
| 60 | break; |
| 61 | end = find_next_bit(cma->bitmap, cma->count, start); |
| 62 | maxchunk = max(end - start, maxchunk); |
| 63 | } |
| 64 | mutex_unlock(&cma->lock); |
| 65 | *val = (u64)maxchunk << cma->order_per_bit; |
| 66 | |
| 67 | return 0; |
| 68 | } |
Dmitry Safonov | 2e32b94 | 2015-04-15 16:14:59 -0700 | [diff] [blame] | 69 | DEFINE_SIMPLE_ATTRIBUTE(cma_maxchunk_fops, cma_maxchunk_get, NULL, "%llu\n"); |
| 70 | |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 71 | static void cma_add_to_cma_mem_list(struct cma *cma, struct cma_mem *mem) |
| 72 | { |
| 73 | spin_lock(&cma->mem_head_lock); |
| 74 | hlist_add_head(&mem->node, &cma->mem_head); |
| 75 | spin_unlock(&cma->mem_head_lock); |
| 76 | } |
| 77 | |
Sasha Levin | 8325330 | 2015-04-14 15:45:02 -0700 | [diff] [blame] | 78 | static struct cma_mem *cma_get_entry_from_list(struct cma *cma) |
| 79 | { |
| 80 | struct cma_mem *mem = NULL; |
| 81 | |
| 82 | spin_lock(&cma->mem_head_lock); |
| 83 | if (!hlist_empty(&cma->mem_head)) { |
| 84 | mem = hlist_entry(cma->mem_head.first, struct cma_mem, node); |
| 85 | hlist_del_init(&mem->node); |
| 86 | } |
| 87 | spin_unlock(&cma->mem_head_lock); |
| 88 | |
| 89 | return mem; |
| 90 | } |
| 91 | |
| 92 | static int cma_free_mem(struct cma *cma, int count) |
| 93 | { |
| 94 | struct cma_mem *mem = NULL; |
| 95 | |
| 96 | while (count) { |
| 97 | mem = cma_get_entry_from_list(cma); |
| 98 | if (mem == NULL) |
| 99 | return 0; |
| 100 | |
| 101 | if (mem->n <= count) { |
| 102 | cma_release(cma, mem->p, mem->n); |
| 103 | count -= mem->n; |
| 104 | kfree(mem); |
| 105 | } else if (cma->order_per_bit == 0) { |
| 106 | cma_release(cma, mem->p, count); |
| 107 | mem->p += count; |
| 108 | mem->n -= count; |
| 109 | count = 0; |
| 110 | cma_add_to_cma_mem_list(cma, mem); |
| 111 | } else { |
| 112 | pr_debug("cma: cannot release partial block when order_per_bit != 0\n"); |
| 113 | cma_add_to_cma_mem_list(cma, mem); |
| 114 | break; |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | return 0; |
| 119 | |
| 120 | } |
| 121 | |
| 122 | static int cma_free_write(void *data, u64 val) |
| 123 | { |
| 124 | int pages = val; |
| 125 | struct cma *cma = data; |
| 126 | |
| 127 | return cma_free_mem(cma, pages); |
| 128 | } |
Sasha Levin | 8325330 | 2015-04-14 15:45:02 -0700 | [diff] [blame] | 129 | DEFINE_SIMPLE_ATTRIBUTE(cma_free_fops, NULL, cma_free_write, "%llu\n"); |
| 130 | |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 131 | static int cma_alloc_mem(struct cma *cma, int count) |
| 132 | { |
| 133 | struct cma_mem *mem; |
| 134 | struct page *p; |
| 135 | |
| 136 | mem = kzalloc(sizeof(*mem), GFP_KERNEL); |
| 137 | if (!mem) |
| 138 | return -ENOMEM; |
| 139 | |
Andrew Morton | 875abdb | 2015-04-14 15:45:05 -0700 | [diff] [blame] | 140 | p = cma_alloc(cma, count, 0); |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 141 | if (!p) { |
| 142 | kfree(mem); |
| 143 | return -ENOMEM; |
| 144 | } |
| 145 | |
| 146 | mem->p = p; |
| 147 | mem->n = count; |
| 148 | |
| 149 | cma_add_to_cma_mem_list(cma, mem); |
| 150 | |
| 151 | return 0; |
| 152 | } |
| 153 | |
| 154 | static int cma_alloc_write(void *data, u64 val) |
| 155 | { |
| 156 | int pages = val; |
| 157 | struct cma *cma = data; |
| 158 | |
| 159 | return cma_alloc_mem(cma, pages); |
| 160 | } |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 161 | DEFINE_SIMPLE_ATTRIBUTE(cma_alloc_fops, NULL, cma_alloc_write, "%llu\n"); |
| 162 | |
Sasha Levin | 28b24c1 | 2015-04-14 15:44:57 -0700 | [diff] [blame] | 163 | static void cma_debugfs_add_one(struct cma *cma, int idx) |
| 164 | { |
| 165 | struct dentry *tmp; |
| 166 | char name[16]; |
| 167 | int u32s; |
| 168 | |
| 169 | sprintf(name, "cma-%d", idx); |
| 170 | |
| 171 | tmp = debugfs_create_dir(name, cma_debugfs_root); |
| 172 | |
Joonsoo Kim | 2292c0b | 2015-07-17 16:24:20 -0700 | [diff] [blame^] | 173 | debugfs_create_file("alloc", S_IWUSR, tmp, cma, |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 174 | &cma_alloc_fops); |
| 175 | |
Joonsoo Kim | 2292c0b | 2015-07-17 16:24:20 -0700 | [diff] [blame^] | 176 | debugfs_create_file("free", S_IWUSR, tmp, cma, |
Sasha Levin | 8325330 | 2015-04-14 15:45:02 -0700 | [diff] [blame] | 177 | &cma_free_fops); |
| 178 | |
Sasha Levin | 28b24c1 | 2015-04-14 15:44:57 -0700 | [diff] [blame] | 179 | debugfs_create_file("base_pfn", S_IRUGO, tmp, |
| 180 | &cma->base_pfn, &cma_debugfs_fops); |
| 181 | debugfs_create_file("count", S_IRUGO, tmp, |
| 182 | &cma->count, &cma_debugfs_fops); |
| 183 | debugfs_create_file("order_per_bit", S_IRUGO, tmp, |
Sasha Levin | 26b02a1 | 2015-04-14 15:44:59 -0700 | [diff] [blame] | 184 | &cma->order_per_bit, &cma_debugfs_fops); |
Dmitry Safonov | 2e32b94 | 2015-04-15 16:14:59 -0700 | [diff] [blame] | 185 | debugfs_create_file("used", S_IRUGO, tmp, cma, &cma_used_fops); |
| 186 | debugfs_create_file("maxchunk", S_IRUGO, tmp, cma, &cma_maxchunk_fops); |
Sasha Levin | 28b24c1 | 2015-04-14 15:44:57 -0700 | [diff] [blame] | 187 | |
| 188 | u32s = DIV_ROUND_UP(cma_bitmap_maxno(cma), BITS_PER_BYTE * sizeof(u32)); |
| 189 | debugfs_create_u32_array("bitmap", S_IRUGO, tmp, (u32*)cma->bitmap, u32s); |
| 190 | } |
| 191 | |
| 192 | static int __init cma_debugfs_init(void) |
| 193 | { |
| 194 | int i; |
| 195 | |
| 196 | cma_debugfs_root = debugfs_create_dir("cma", NULL); |
| 197 | if (!cma_debugfs_root) |
| 198 | return -ENOMEM; |
| 199 | |
| 200 | for (i = 0; i < cma_area_count; i++) |
| 201 | cma_debugfs_add_one(&cma_areas[i], i); |
| 202 | |
| 203 | return 0; |
| 204 | } |
| 205 | late_initcall(cma_debugfs_init); |