Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 1 | /* |
| 2 | * |
Liam Mark | daf65bd | 2017-02-15 13:52:48 -0800 | [diff] [blame] | 3 | * Copyright (c) 2013-2017, The Linux Foundation. All rights reserved. |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 4 | * Copyright (C) 2000-2004 Russell King |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 10 | #include <linux/bootmem.h> |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 11 | #include <linux/module.h> |
| 12 | #include <linux/mm.h> |
| 13 | #include <linux/gfp.h> |
| 14 | #include <linux/errno.h> |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 15 | #include <linux/ioport.h> |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 16 | #include <linux/list.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/device.h> |
| 19 | #include <linux/dma-mapping.h> |
| 20 | #include <linux/dma-contiguous.h> |
| 21 | #include <linux/highmem.h> |
| 22 | #include <linux/memblock.h> |
| 23 | #include <linux/slab.h> |
| 24 | #include <linux/iommu.h> |
| 25 | #include <linux/io.h> |
| 26 | #include <linux/vmalloc.h> |
| 27 | #include <linux/sizes.h> |
| 28 | #include <linux/spinlock.h> |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 29 | #include <asm/dma-contiguous.h> |
| 30 | #include <asm/tlbflush.h> |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 31 | |
| 32 | struct removed_region { |
Shiraz Hashim | 28de437 | 2015-09-02 12:01:55 +0530 | [diff] [blame] | 33 | phys_addr_t base; |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 34 | int nr_pages; |
| 35 | unsigned long *bitmap; |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 36 | int fixup; |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 37 | struct mutex lock; |
| 38 | }; |
| 39 | |
| 40 | #define NO_KERNEL_MAPPING_DUMMY 0x2222 |
| 41 | |
| 42 | static int dma_init_removed_memory(phys_addr_t phys_addr, size_t size, |
| 43 | struct removed_region **mem) |
| 44 | { |
| 45 | struct removed_region *dma_mem = NULL; |
| 46 | int pages = size >> PAGE_SHIFT; |
| 47 | int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); |
| 48 | |
| 49 | dma_mem = kzalloc(sizeof(struct removed_region), GFP_KERNEL); |
| 50 | if (!dma_mem) |
| 51 | goto out; |
| 52 | dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); |
| 53 | if (!dma_mem->bitmap) |
| 54 | goto free1_out; |
| 55 | |
| 56 | dma_mem->base = phys_addr; |
| 57 | dma_mem->nr_pages = pages; |
| 58 | mutex_init(&dma_mem->lock); |
| 59 | |
| 60 | *mem = dma_mem; |
| 61 | |
| 62 | return 0; |
| 63 | |
| 64 | free1_out: |
| 65 | kfree(dma_mem); |
| 66 | out: |
| 67 | return -ENOMEM; |
| 68 | } |
| 69 | |
| 70 | static int dma_assign_removed_region(struct device *dev, |
| 71 | struct removed_region *mem) |
| 72 | { |
| 73 | if (dev->removed_mem) |
| 74 | return -EBUSY; |
| 75 | |
| 76 | dev->removed_mem = mem; |
| 77 | return 0; |
| 78 | } |
| 79 | |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 80 | static void adapt_iomem_resource(unsigned long base_pfn, unsigned long end_pfn) |
| 81 | { |
| 82 | struct resource *res, *conflict; |
| 83 | resource_size_t cstart, cend; |
| 84 | |
| 85 | res = kzalloc(sizeof(*res), GFP_KERNEL); |
| 86 | if (!res) |
| 87 | return; |
| 88 | |
| 89 | res->name = "System RAM"; |
| 90 | res->start = __pfn_to_phys(base_pfn); |
| 91 | res->end = __pfn_to_phys(end_pfn) - 1; |
| 92 | res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
| 93 | |
| 94 | conflict = request_resource_conflict(&iomem_resource, res); |
| 95 | if (!conflict) { |
| 96 | pr_err("Removed memory: no conflict resource found\n"); |
| 97 | kfree(res); |
| 98 | goto done; |
| 99 | } |
| 100 | |
| 101 | cstart = conflict->start; |
| 102 | cend = conflict->end; |
| 103 | if ((cstart == res->start) && (cend == res->end)) { |
| 104 | release_resource(conflict); |
| 105 | } else if ((res->start >= cstart) && (res->start <= cend)) { |
| 106 | if (res->start == cstart) { |
| 107 | adjust_resource(conflict, res->end + 1, |
| 108 | cend - res->end); |
| 109 | } else if (res->end == cend) { |
| 110 | adjust_resource(conflict, cstart, |
| 111 | res->start - cstart); |
| 112 | } else { |
| 113 | adjust_resource(conflict, cstart, |
| 114 | res->start - cstart); |
| 115 | res->start = res->end + 1; |
| 116 | res->end = cend; |
| 117 | request_resource(&iomem_resource, res); |
| 118 | goto done; |
| 119 | } |
| 120 | } else { |
| 121 | pr_err("Removed memory: incorrect resource conflict start=%llx end=%llx\n", |
| 122 | (unsigned long long) conflict->start, |
| 123 | (unsigned long long) conflict->end); |
| 124 | } |
| 125 | |
| 126 | kfree(res); |
| 127 | done: |
| 128 | return; |
| 129 | } |
| 130 | |
| 131 | #ifdef CONFIG_FLATMEM |
| 132 | static void free_memmap(unsigned long start_pfn, unsigned long end_pfn) |
| 133 | { |
| 134 | struct page *start_pg, *end_pg; |
| 135 | unsigned long pg, pgend; |
| 136 | |
Shiraz Hashim | ba72478 | 2016-04-11 16:45:13 +0530 | [diff] [blame] | 137 | start_pfn = ALIGN(start_pfn, pageblock_nr_pages); |
| 138 | end_pfn = round_down(end_pfn, pageblock_nr_pages); |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 139 | /* |
| 140 | * Convert start_pfn/end_pfn to a struct page pointer. |
| 141 | */ |
| 142 | start_pg = pfn_to_page(start_pfn - 1) + 1; |
| 143 | end_pg = pfn_to_page(end_pfn - 1) + 1; |
| 144 | |
| 145 | /* |
| 146 | * Convert to physical addresses, and round start upwards and end |
| 147 | * downwards. |
| 148 | */ |
| 149 | pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); |
| 150 | pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; |
| 151 | |
| 152 | /* |
| 153 | * If there are free pages between these, free the section of the |
| 154 | * memmap array. |
| 155 | */ |
| 156 | if (pg < pgend) |
| 157 | free_bootmem_late(pg, pgend - pg); |
| 158 | } |
| 159 | #else |
| 160 | static void free_memmap(unsigned long start_pfn, unsigned long end_pfn) |
| 161 | { |
| 162 | } |
| 163 | #endif |
| 164 | |
| 165 | static int _clear_pte(pte_t *pte, pgtable_t token, unsigned long addr, |
| 166 | void *data) |
| 167 | { |
| 168 | pte_clear(&init_mm, addr, pte); |
| 169 | return 0; |
| 170 | } |
| 171 | |
| 172 | static void clear_mapping(unsigned long addr, unsigned long size) |
| 173 | { |
| 174 | apply_to_page_range(&init_mm, addr, size, _clear_pte, NULL); |
| 175 | /* ensure ptes are updated */ |
| 176 | mb(); |
| 177 | flush_tlb_kernel_range(addr, addr + size); |
| 178 | } |
| 179 | |
| 180 | static void removed_region_fixup(struct removed_region *dma_mem, int index) |
| 181 | { |
| 182 | unsigned long fixup_size; |
| 183 | unsigned long base_pfn; |
Shiraz Hashim | 3eaf6e6 | 2016-04-16 11:43:02 +0530 | [diff] [blame] | 184 | unsigned long flags; |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 185 | |
| 186 | if (index > dma_mem->nr_pages) |
| 187 | return; |
| 188 | |
| 189 | /* carve-out */ |
Shiraz Hashim | 3eaf6e6 | 2016-04-16 11:43:02 +0530 | [diff] [blame] | 190 | flags = memblock_region_resize_late_begin(); |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 191 | memblock_free(dma_mem->base, dma_mem->nr_pages * PAGE_SIZE); |
| 192 | memblock_remove(dma_mem->base, index * PAGE_SIZE); |
Shiraz Hashim | 3eaf6e6 | 2016-04-16 11:43:02 +0530 | [diff] [blame] | 193 | memblock_region_resize_late_end(flags); |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 194 | |
| 195 | /* clear page-mappings */ |
| 196 | base_pfn = dma_mem->base >> PAGE_SHIFT; |
| 197 | if (!PageHighMem(pfn_to_page(base_pfn))) { |
| 198 | clear_mapping((unsigned long) phys_to_virt(dma_mem->base), |
| 199 | index * PAGE_SIZE); |
| 200 | } |
| 201 | |
| 202 | /* free page objects */ |
| 203 | free_memmap(base_pfn, base_pfn + index); |
| 204 | |
| 205 | /* return remaining area to system */ |
| 206 | fixup_size = (dma_mem->nr_pages - index) * PAGE_SIZE; |
| 207 | free_bootmem_late(dma_mem->base + index * PAGE_SIZE, fixup_size); |
| 208 | |
| 209 | /* |
| 210 | * release freed resource region so as to show up under iomem resource |
| 211 | * list |
| 212 | */ |
| 213 | adapt_iomem_resource(base_pfn, base_pfn + index); |
| 214 | |
| 215 | /* limit the fixup region */ |
| 216 | dma_mem->nr_pages = index; |
| 217 | } |
| 218 | |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 219 | void *removed_alloc(struct device *dev, size_t size, dma_addr_t *handle, |
| 220 | gfp_t gfp, unsigned long attrs) |
| 221 | { |
| 222 | bool no_kernel_mapping = attrs & DMA_ATTR_NO_KERNEL_MAPPING; |
| 223 | bool skip_zeroing = attrs & DMA_ATTR_SKIP_ZEROING; |
| 224 | int pageno; |
Shiraz Hashim | dd9cc4c | 2015-09-12 12:31:10 +0530 | [diff] [blame] | 225 | unsigned long order; |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 226 | void *addr = NULL; |
| 227 | struct removed_region *dma_mem = dev->removed_mem; |
Shiraz Hashim | dd9cc4c | 2015-09-12 12:31:10 +0530 | [diff] [blame] | 228 | int nbits; |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 229 | unsigned int align; |
| 230 | |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 231 | if (!gfpflags_allow_blocking(gfp)) |
| 232 | return NULL; |
| 233 | |
Shiraz Hashim | dd9cc4c | 2015-09-12 12:31:10 +0530 | [diff] [blame] | 234 | size = PAGE_ALIGN(size); |
| 235 | nbits = size >> PAGE_SHIFT; |
| 236 | order = get_order(size); |
| 237 | |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 238 | if (order > get_order(SZ_1M)) |
| 239 | order = get_order(SZ_1M); |
| 240 | |
| 241 | align = (1 << order) - 1; |
| 242 | |
| 243 | |
| 244 | mutex_lock(&dma_mem->lock); |
| 245 | pageno = bitmap_find_next_zero_area(dma_mem->bitmap, dma_mem->nr_pages, |
| 246 | 0, nbits, align); |
| 247 | |
| 248 | if (pageno < dma_mem->nr_pages) { |
| 249 | phys_addr_t base = dma_mem->base + pageno * PAGE_SIZE; |
| 250 | *handle = base; |
| 251 | |
| 252 | bitmap_set(dma_mem->bitmap, pageno, nbits); |
| 253 | |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 254 | if (dma_mem->fixup) { |
| 255 | removed_region_fixup(dma_mem, pageno + nbits); |
| 256 | dma_mem->fixup = 0; |
| 257 | } |
| 258 | |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 259 | if (no_kernel_mapping && skip_zeroing) { |
| 260 | addr = (void *)NO_KERNEL_MAPPING_DUMMY; |
| 261 | goto out; |
| 262 | } |
| 263 | |
| 264 | addr = ioremap(base, size); |
| 265 | if (WARN_ON(!addr)) { |
| 266 | bitmap_clear(dma_mem->bitmap, pageno, nbits); |
| 267 | } else { |
| 268 | if (!skip_zeroing) |
Shiraz Hashim | 3025b45 | 2015-09-12 16:47:30 +0530 | [diff] [blame] | 269 | memset_io(addr, 0, size); |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 270 | if (no_kernel_mapping) { |
| 271 | iounmap(addr); |
| 272 | addr = (void *)NO_KERNEL_MAPPING_DUMMY; |
| 273 | } |
| 274 | *handle = base; |
| 275 | } |
| 276 | } |
| 277 | |
| 278 | out: |
| 279 | mutex_unlock(&dma_mem->lock); |
| 280 | return addr; |
| 281 | } |
| 282 | |
| 283 | |
| 284 | int removed_mmap(struct device *dev, struct vm_area_struct *vma, |
| 285 | void *cpu_addr, dma_addr_t dma_addr, size_t size, |
| 286 | unsigned long attrs) |
| 287 | { |
| 288 | return -ENXIO; |
| 289 | } |
| 290 | |
| 291 | void removed_free(struct device *dev, size_t size, void *cpu_addr, |
| 292 | dma_addr_t handle, unsigned long attrs) |
| 293 | { |
| 294 | bool no_kernel_mapping = attrs & DMA_ATTR_NO_KERNEL_MAPPING; |
| 295 | struct removed_region *dma_mem = dev->removed_mem; |
| 296 | |
Liam Mark | daf65bd | 2017-02-15 13:52:48 -0800 | [diff] [blame] | 297 | size = PAGE_ALIGN(size); |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 298 | if (!no_kernel_mapping) |
| 299 | iounmap(cpu_addr); |
| 300 | mutex_lock(&dma_mem->lock); |
| 301 | bitmap_clear(dma_mem->bitmap, (handle - dma_mem->base) >> PAGE_SHIFT, |
| 302 | size >> PAGE_SHIFT); |
| 303 | mutex_unlock(&dma_mem->lock); |
| 304 | } |
| 305 | |
| 306 | static dma_addr_t removed_map_page(struct device *dev, struct page *page, |
| 307 | unsigned long offset, size_t size, |
| 308 | enum dma_data_direction dir, |
| 309 | unsigned long attrs) |
| 310 | { |
| 311 | return ~(dma_addr_t)0; |
| 312 | } |
| 313 | |
| 314 | static void removed_unmap_page(struct device *dev, dma_addr_t dma_handle, |
| 315 | size_t size, enum dma_data_direction dir, |
| 316 | unsigned long attrs) |
| 317 | { |
| 318 | } |
| 319 | |
| 320 | static int removed_map_sg(struct device *dev, struct scatterlist *sg, |
| 321 | int nents, enum dma_data_direction dir, |
| 322 | unsigned long attrs) |
| 323 | { |
| 324 | return 0; |
| 325 | } |
| 326 | |
| 327 | static void removed_unmap_sg(struct device *dev, |
| 328 | struct scatterlist *sg, int nents, |
| 329 | enum dma_data_direction dir, |
| 330 | unsigned long attrs) |
| 331 | { |
| 332 | } |
| 333 | |
| 334 | static void removed_sync_single_for_cpu(struct device *dev, |
| 335 | dma_addr_t dma_handle, size_t size, |
| 336 | enum dma_data_direction dir) |
| 337 | { |
| 338 | } |
| 339 | |
| 340 | void removed_sync_single_for_device(struct device *dev, |
| 341 | dma_addr_t dma_handle, size_t size, |
| 342 | enum dma_data_direction dir) |
| 343 | { |
| 344 | } |
| 345 | |
| 346 | void removed_sync_sg_for_cpu(struct device *dev, |
| 347 | struct scatterlist *sg, int nents, |
| 348 | enum dma_data_direction dir) |
| 349 | { |
| 350 | } |
| 351 | |
| 352 | void removed_sync_sg_for_device(struct device *dev, |
| 353 | struct scatterlist *sg, int nents, |
| 354 | enum dma_data_direction dir) |
| 355 | { |
| 356 | } |
| 357 | |
| 358 | void *removed_remap(struct device *dev, void *cpu_addr, dma_addr_t handle, |
| 359 | size_t size, unsigned long attrs) |
| 360 | { |
| 361 | return ioremap(handle, size); |
| 362 | } |
| 363 | |
| 364 | void removed_unremap(struct device *dev, void *remapped_address, size_t size) |
| 365 | { |
| 366 | iounmap(remapped_address); |
| 367 | } |
| 368 | |
| 369 | const struct dma_map_ops removed_dma_ops = { |
| 370 | .alloc = removed_alloc, |
| 371 | .free = removed_free, |
| 372 | .mmap = removed_mmap, |
| 373 | .map_page = removed_map_page, |
| 374 | .unmap_page = removed_unmap_page, |
| 375 | .map_sg = removed_map_sg, |
| 376 | .unmap_sg = removed_unmap_sg, |
| 377 | .sync_single_for_cpu = removed_sync_single_for_cpu, |
| 378 | .sync_single_for_device = removed_sync_single_for_device, |
| 379 | .sync_sg_for_cpu = removed_sync_sg_for_cpu, |
| 380 | .sync_sg_for_device = removed_sync_sg_for_device, |
| 381 | .remap = removed_remap, |
| 382 | .unremap = removed_unremap, |
| 383 | }; |
| 384 | EXPORT_SYMBOL(removed_dma_ops); |
| 385 | |
| 386 | #ifdef CONFIG_OF_RESERVED_MEM |
| 387 | #include <linux/of.h> |
| 388 | #include <linux/of_fdt.h> |
| 389 | #include <linux/of_reserved_mem.h> |
| 390 | |
| 391 | static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev) |
| 392 | { |
| 393 | struct removed_region *mem = rmem->priv; |
| 394 | |
| 395 | if (!mem && dma_init_removed_memory(rmem->base, rmem->size, &mem)) { |
| 396 | pr_info("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n", |
| 397 | &rmem->base, (unsigned long)rmem->size / SZ_1M); |
| 398 | return -EINVAL; |
| 399 | } |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 400 | mem->fixup = rmem->fixup; |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 401 | set_dma_ops(dev, &removed_dma_ops); |
| 402 | rmem->priv = mem; |
| 403 | dma_assign_removed_region(dev, mem); |
| 404 | return 0; |
| 405 | } |
| 406 | |
| 407 | static void rmem_dma_device_release(struct reserved_mem *rmem, |
| 408 | struct device *dev) |
| 409 | { |
| 410 | dev->dma_mem = NULL; |
| 411 | } |
| 412 | |
| 413 | static const struct reserved_mem_ops removed_mem_ops = { |
| 414 | .device_init = rmem_dma_device_init, |
| 415 | .device_release = rmem_dma_device_release, |
| 416 | }; |
| 417 | |
| 418 | static int __init removed_dma_setup(struct reserved_mem *rmem) |
| 419 | { |
Patrick Daly | b5520a5 | 2016-08-17 15:43:08 -0700 | [diff] [blame] | 420 | unsigned long node = rmem->fdt_node; |
| 421 | int nomap, fixup; |
| 422 | |
| 423 | nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL; |
| 424 | fixup = of_get_flat_dt_prop(node, "no-map-fixup", NULL) != NULL; |
| 425 | |
| 426 | if (nomap && fixup) { |
| 427 | pr_err("Removed memory: nomap & nomap-fixup can't co-exist\n"); |
| 428 | return -EINVAL; |
| 429 | } |
| 430 | |
| 431 | rmem->fixup = fixup; |
| 432 | if (rmem->fixup) { |
| 433 | /* Architecture specific contiguous memory fixup only for |
| 434 | * no-map-fixup to split mappings |
| 435 | */ |
| 436 | dma_contiguous_early_fixup(rmem->base, rmem->size); |
| 437 | } |
| 438 | |
Laura Abbott | f971607 | 2014-08-05 18:47:54 -0700 | [diff] [blame] | 439 | rmem->ops = &removed_mem_ops; |
| 440 | pr_info("Removed memory: created DMA memory pool at %pa, size %ld MiB\n", |
| 441 | &rmem->base, (unsigned long)rmem->size / SZ_1M); |
| 442 | return 0; |
| 443 | } |
| 444 | RESERVEDMEM_OF_DECLARE(dma, "removed-dma-pool", removed_dma_setup); |
| 445 | #endif |