arch/arm64/mm/dma-mapping.c

   1 /*
   2  * SWIOTLB-based DMA API implementation
   3  *
   4  * Copyright (C) 2012 ARM Ltd.
   5  * Author: Catalin Marinas <catalin.marinas@arm.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <linux/gfp.h>
  21 #include <linux/export.h>
  22 #include <linux/slab.h>
  23 #include <linux/dma-mapping.h>
  24 #include <linux/dma-contiguous.h>
  25 #include <linux/vmalloc.h>
  26 #include <linux/swiotlb.h>
  27
  28 #include <asm/cacheflush.h>
  29
  30 struct dma_map_ops *dma_ops;
  31 EXPORT_SYMBOL(dma_ops);
  32
  33 static pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot,
  34                                  bool coherent)
  35 {
  36         if (!coherent || dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs))
  37                 return pgprot_writecombine(prot);
  38         return prot;
  39 }
  40
  41 static void *__dma_alloc_coherent(struct device *dev, size_t size,
  42                                   dma_addr_t *dma_handle, gfp_t flags,
  43                                   struct dma_attrs *attrs)
  44 {
  45         if (dev == NULL) {
  46                 WARN_ONCE(1, "Use an actual device structure for DMA allocation\n");
  47                 return NULL;
  48         }
  49
  50         if (IS_ENABLED(CONFIG_ZONE_DMA) &&
  51             dev->coherent_dma_mask <= DMA_BIT_MASK(32))
  52                 flags |= GFP_DMA;
  53         if (IS_ENABLED(CONFIG_DMA_CMA)) {
  54                 struct page *page;
  55
  56                 size = PAGE_ALIGN(size);
  57                 page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,
  58                                                         get_order(size));
  59                 if (!page)
  60                         return NULL;
  61
  62                 *dma_handle = phys_to_dma(dev, page_to_phys(page));
  63                 return page_address(page);
  64         } else {
  65                 return swiotlb_alloc_coherent(dev, size, dma_handle, flags);
  66         }
  67 }
  68
  69 static void __dma_free_coherent(struct device *dev, size_t size,
  70                                 void *vaddr, dma_addr_t dma_handle,
  71                                 struct dma_attrs *attrs)
  72 {
  73         if (dev == NULL) {
  74                 WARN_ONCE(1, "Use an actual device structure for DMA allocation\n");
  75                 return;
  76         }
  77
  78         if (IS_ENABLED(CONFIG_DMA_CMA)) {
  79                 phys_addr_t paddr = dma_to_phys(dev, dma_handle);
  80
  81                 dma_release_from_contiguous(dev,
  82                                         phys_to_page(paddr),
  83                                         size >> PAGE_SHIFT);
  84         } else {
  85                 swiotlb_free_coherent(dev, size, vaddr, dma_handle);
  86         }
  87 }
  88
  89 static void *__dma_alloc_noncoherent(struct device *dev, size_t size,
  90                                      dma_addr_t *dma_handle, gfp_t flags,
  91                                      struct dma_attrs *attrs)
  92 {
  93         struct page *page, **map;
  94         void *ptr, *coherent_ptr;
  95         int order, i;
  96
  97         size = PAGE_ALIGN(size);
  98         order = get_order(size);
  99
 100         ptr = __dma_alloc_coherent(dev, size, dma_handle, flags, attrs);
 101         if (!ptr)
 102                 goto no_mem;
 103         map = kmalloc(sizeof(struct page *) << order, flags & ~GFP_DMA);
 104         if (!map)
 105                 goto no_map;
 106
 107         /* remove any dirty cache lines on the kernel alias */
 108         __dma_flush_range(ptr, ptr + size);
 109
 110         /* create a coherent mapping */
 111         page = virt_to_page(ptr);
 112         for (i = 0; i < (size >> PAGE_SHIFT); i++)
 113                 map[i] = page + i;
 114         coherent_ptr = vmap(map, size >> PAGE_SHIFT, VM_MAP,
 115                             __get_dma_pgprot(attrs, pgprot_default, false));
 116         kfree(map);
 117         if (!coherent_ptr)
 118                 goto no_map;
 119
 120         return coherent_ptr;
 121
 122 no_map:
 123         __dma_free_coherent(dev, size, ptr, *dma_handle, attrs);
 124 no_mem:
 125         *dma_handle = ~0;
 126         return NULL;
 127 }
 128
 129 static void __dma_free_noncoherent(struct device *dev, size_t size,
 130                                    void *vaddr, dma_addr_t dma_handle,
 131                                    struct dma_attrs *attrs)
 132 {
 133         void *swiotlb_addr = phys_to_virt(dma_to_phys(dev, dma_handle));
 134
 135         vunmap(vaddr);
 136         __dma_free_coherent(dev, size, swiotlb_addr, dma_handle, attrs);
 137 }
 138
 139 static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
 140                                      unsigned long offset, size_t size,
 141                                      enum dma_data_direction dir,
 142                                      struct dma_attrs *attrs)
 143 {
 144         dma_addr_t dev_addr;
 145
 146         dev_addr = swiotlb_map_page(dev, page, offset, size, dir, attrs);
 147         __dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 148
 149         return dev_addr;
 150 }
 151
 152
 153 static void __swiotlb_unmap_page(struct device *dev, dma_addr_t dev_addr,
 154                                  size_t size, enum dma_data_direction dir,
 155                                  struct dma_attrs *attrs)
 156 {
 157         __dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 158         swiotlb_unmap_page(dev, dev_addr, size, dir, attrs);
 159 }
 160
 161 static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
 162                                   int nelems, enum dma_data_direction dir,
 163                                   struct dma_attrs *attrs)
 164 {
 165         struct scatterlist *sg;
 166         int i, ret;
 167
 168         ret = swiotlb_map_sg_attrs(dev, sgl, nelems, dir, attrs);
 169         for_each_sg(sgl, sg, ret, i)
 170                 __dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
 171                                sg->length, dir);
 172
 173         return ret;
 174 }
 175
 176 static void __swiotlb_unmap_sg_attrs(struct device *dev,
 177                                      struct scatterlist *sgl, int nelems,
 178                                      enum dma_data_direction dir,
 179                                      struct dma_attrs *attrs)
 180 {
 181         struct scatterlist *sg;
 182         int i;
 183
 184         for_each_sg(sgl, sg, nelems, i)
 185                 __dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
 186                                  sg->length, dir);
 187         swiotlb_unmap_sg_attrs(dev, sgl, nelems, dir, attrs);
 188 }
 189
 190 static void __swiotlb_sync_single_for_cpu(struct device *dev,
 191                                           dma_addr_t dev_addr, size_t size,
 192                                           enum dma_data_direction dir)
 193 {
 194         __dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 195         swiotlb_sync_single_for_cpu(dev, dev_addr, size, dir);
 196 }
 197
 198 static void __swiotlb_sync_single_for_device(struct device *dev,
 199                                              dma_addr_t dev_addr, size_t size,
 200                                              enum dma_data_direction dir)
 201 {
 202         swiotlb_sync_single_for_device(dev, dev_addr, size, dir);
 203         __dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 204 }
 205
 206 static void __swiotlb_sync_sg_for_cpu(struct device *dev,
 207                                       struct scatterlist *sgl, int nelems,
 208                                       enum dma_data_direction dir)
 209 {
 210         struct scatterlist *sg;
 211         int i;
 212
 213         for_each_sg(sgl, sg, nelems, i)
 214                 __dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
 215                                  sg->length, dir);
 216         swiotlb_sync_sg_for_cpu(dev, sgl, nelems, dir);
 217 }
 218
 219 static void __swiotlb_sync_sg_for_device(struct device *dev,
 220                                          struct scatterlist *sgl, int nelems,
 221                                          enum dma_data_direction dir)
 222 {
 223         struct scatterlist *sg;
 224         int i;
 225
 226         swiotlb_sync_sg_for_device(dev, sgl, nelems, dir);
 227         for_each_sg(sgl, sg, nelems, i)
 228                 __dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
 229                                sg->length, dir);
 230 }
 231
 232 /* vma->vm_page_prot must be set appropriately before calling this function */
 233 static int __dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
 234                              void *cpu_addr, dma_addr_t dma_addr, size_t size)
 235 {
 236         int ret = -ENXIO;
 237         unsigned long nr_vma_pages = (vma->vm_end - vma->vm_start) >>
 238                                         PAGE_SHIFT;
 239         unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
 240         unsigned long pfn = dma_to_phys(dev, dma_addr) >> PAGE_SHIFT;
 241         unsigned long off = vma->vm_pgoff;
 242
 243         if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
 244                 return ret;
 245
 246         if (off < nr_pages && nr_vma_pages <= (nr_pages - off)) {
 247                 ret = remap_pfn_range(vma, vma->vm_start,
 248                                       pfn + off,
 249                                       vma->vm_end - vma->vm_start,
 250                                       vma->vm_page_prot);
 251         }
 252
 253         return ret;
 254 }
 255
 256 static int __swiotlb_mmap_noncoherent(struct device *dev,
 257                 struct vm_area_struct *vma,
 258                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
 259                 struct dma_attrs *attrs)
 260 {
 261         vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot, false);
 262         return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
 263 }
 264
 265 static int __swiotlb_mmap_coherent(struct device *dev,
 266                 struct vm_area_struct *vma,
 267                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
 268                 struct dma_attrs *attrs)
 269 {
 270         /* Just use whatever page_prot attributes were specified */
 271         return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
 272 }
 273
 274 struct dma_map_ops noncoherent_swiotlb_dma_ops = {
 275         .alloc = __dma_alloc_noncoherent,
 276         .free = __dma_free_noncoherent,
 277         .mmap = __swiotlb_mmap_noncoherent,
 278         .map_page = __swiotlb_map_page,
 279         .unmap_page = __swiotlb_unmap_page,
 280         .map_sg = __swiotlb_map_sg_attrs,
 281         .unmap_sg = __swiotlb_unmap_sg_attrs,
 282         .sync_single_for_cpu = __swiotlb_sync_single_for_cpu,
 283         .sync_single_for_device = __swiotlb_sync_single_for_device,
 284         .sync_sg_for_cpu = __swiotlb_sync_sg_for_cpu,
 285         .sync_sg_for_device = __swiotlb_sync_sg_for_device,
 286         .dma_supported = swiotlb_dma_supported,
 287         .mapping_error = swiotlb_dma_mapping_error,
 288 };
 289 EXPORT_SYMBOL(noncoherent_swiotlb_dma_ops);
 290
 291 struct dma_map_ops coherent_swiotlb_dma_ops = {
 292         .alloc = __dma_alloc_coherent,
 293         .free = __dma_free_coherent,
 294         .mmap = __swiotlb_mmap_coherent,
 295         .map_page = swiotlb_map_page,
 296         .unmap_page = swiotlb_unmap_page,
 297         .map_sg = swiotlb_map_sg_attrs,
 298         .unmap_sg = swiotlb_unmap_sg_attrs,
 299         .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
 300         .sync_single_for_device = swiotlb_sync_single_for_device,
 301         .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
 302         .sync_sg_for_device = swiotlb_sync_sg_for_device,
 303         .dma_supported = swiotlb_dma_supported,
 304         .mapping_error = swiotlb_dma_mapping_error,
 305 };
 306 EXPORT_SYMBOL(coherent_swiotlb_dma_ops);
 307
 308 extern int swiotlb_late_init_with_default_size(size_t default_size);
 309
 310 static int __init swiotlb_late_init(void)
 311 {
 312         size_t swiotlb_size = min(SZ_64M, MAX_ORDER_NR_PAGES << PAGE_SHIFT);
 313
 314         dma_ops = &coherent_swiotlb_dma_ops;
 315
 316         return swiotlb_late_init_with_default_size(swiotlb_size);
 317 }
 318 subsys_initcall(swiotlb_late_init);
 319
 320 #define PREALLOC_DMA_DEBUG_ENTRIES      4096
 321
 322 static int __init dma_debug_do_init(void)
 323 {
 324         dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
 325         return 0;
 326 }
 327 fs_initcall(dma_debug_do_init);