drivers/base/dma-mapping.c

   1 /*
   2  * drivers/base/dma-mapping.c - arch-independent dma-mapping routines
   3  *
   4  * Copyright (c) 2006  SUSE Linux Products GmbH
   5  * Copyright (c) 2006  Tejun Heo <teheo@suse.de>
   6  *
   7  * This file is released under the GPLv2.
   8  */
   9
  10 #include <linux/acpi.h>
  11 #include <linux/dma-mapping.h>
  12 #include <linux/export.h>
  13 #include <linux/gfp.h>
  14 #include <linux/of_device.h>
  15 #include <linux/slab.h>
  16 #include <linux/vmalloc.h>
  17
  18 /*
  19  * Managed DMA API
  20  */
  21 struct dma_devres {
  22         size_t          size;
  23         void            *vaddr;
  24         dma_addr_t      dma_handle;
  25         unsigned long   attrs;
  26 };
  27
  28 static void dmam_release(struct device *dev, void *res)
  29 {
  30         struct dma_devres *this = res;
  31
  32         dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,
  33                         this->attrs);
  34 }
  35
  36 static int dmam_match(struct device *dev, void *res, void *match_data)
  37 {
  38         struct dma_devres *this = res, *match = match_data;
  39
  40         if (this->vaddr == match->vaddr) {
  41                 WARN_ON(this->size != match->size ||
  42                         this->dma_handle != match->dma_handle);
  43                 return 1;
  44         }
  45         return 0;
  46 }
  47
  48 /**
  49  * dmam_alloc_coherent - Managed dma_alloc_coherent()
  50  * @dev: Device to allocate coherent memory for
  51  * @size: Size of allocation
  52  * @dma_handle: Out argument for allocated DMA handle
  53  * @gfp: Allocation flags
  54  *
  55  * Managed dma_alloc_coherent().  Memory allocated using this function
  56  * will be automatically released on driver detach.
  57  *
  58  * RETURNS:
  59  * Pointer to allocated memory on success, NULL on failure.
  60  */
  61 void *dmam_alloc_coherent(struct device *dev, size_t size,
  62                            dma_addr_t *dma_handle, gfp_t gfp)
  63 {
  64         struct dma_devres *dr;
  65         void *vaddr;
  66
  67         dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
  68         if (!dr)
  69                 return NULL;
  70
  71         vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
  72         if (!vaddr) {
  73                 devres_free(dr);
  74                 return NULL;
  75         }
  76
  77         dr->vaddr = vaddr;
  78         dr->dma_handle = *dma_handle;
  79         dr->size = size;
  80
  81         devres_add(dev, dr);
  82
  83         return vaddr;
  84 }
  85 EXPORT_SYMBOL(dmam_alloc_coherent);
  86
  87 /**
  88  * dmam_free_coherent - Managed dma_free_coherent()
  89  * @dev: Device to free coherent memory for
  90  * @size: Size of allocation
  91  * @vaddr: Virtual address of the memory to free
  92  * @dma_handle: DMA handle of the memory to free
  93  *
  94  * Managed dma_free_coherent().
  95  */
  96 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
  97                         dma_addr_t dma_handle)
  98 {
  99         struct dma_devres match_data = { size, vaddr, dma_handle };
 100
 101         dma_free_coherent(dev, size, vaddr, dma_handle);
 102         WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));
 103 }
 104 EXPORT_SYMBOL(dmam_free_coherent);
 105
 106 /**
 107  * dmam_alloc_attrs - Managed dma_alloc_attrs()
 108  * @dev: Device to allocate non_coherent memory for
 109  * @size: Size of allocation
 110  * @dma_handle: Out argument for allocated DMA handle
 111  * @gfp: Allocation flags
 112  * @attrs: Flags in the DMA_ATTR_* namespace.
 113  *
 114  * Managed dma_alloc_attrs().  Memory allocated using this function will be
 115  * automatically released on driver detach.
 116  *
 117  * RETURNS:
 118  * Pointer to allocated memory on success, NULL on failure.
 119  */
 120 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 121                 gfp_t gfp, unsigned long attrs)
 122 {
 123         struct dma_devres *dr;
 124         void *vaddr;
 125
 126         dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
 127         if (!dr)
 128                 return NULL;
 129
 130         vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
 131         if (!vaddr) {
 132                 devres_free(dr);
 133                 return NULL;
 134         }
 135
 136         dr->vaddr = vaddr;
 137         dr->dma_handle = *dma_handle;
 138         dr->size = size;
 139         dr->attrs = attrs;
 140
 141         devres_add(dev, dr);
 142
 143         return vaddr;
 144 }
 145 EXPORT_SYMBOL(dmam_alloc_attrs);
 146
 147 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
 148
 149 static void dmam_coherent_decl_release(struct device *dev, void *res)
 150 {
 151         dma_release_declared_memory(dev);
 152 }
 153
 154 /**
 155  * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
 156  * @dev: Device to declare coherent memory for
 157  * @phys_addr: Physical address of coherent memory to be declared
 158  * @device_addr: Device address of coherent memory to be declared
 159  * @size: Size of coherent memory to be declared
 160  * @flags: Flags
 161  *
 162  * Managed dma_declare_coherent_memory().
 163  *
 164  * RETURNS:
 165  * 0 on success, -errno on failure.
 166  */
 167 int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
 168                                  dma_addr_t device_addr, size_t size, int flags)
 169 {
 170         void *res;
 171         int rc;
 172
 173         res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
 174         if (!res)
 175                 return -ENOMEM;
 176
 177         rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
 178                                          flags);
 179         if (rc) {
 180                 devres_add(dev, res);
 181                 rc = 0;
 182         } else {
 183                 devres_free(res);
 184                 rc = -ENOMEM;
 185         }
 186
 187         return rc;
 188 }
 189 EXPORT_SYMBOL(dmam_declare_coherent_memory);
 190
 191 /**
 192  * dmam_release_declared_memory - Managed dma_release_declared_memory().
 193  * @dev: Device to release declared coherent memory for
 194  *
 195  * Managed dmam_release_declared_memory().
 196  */
 197 void dmam_release_declared_memory(struct device *dev)
 198 {
 199         WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
 200 }
 201 EXPORT_SYMBOL(dmam_release_declared_memory);
 202
 203 #endif
 204
 205 /*
 206  * Create scatter-list for the already allocated DMA buffer.
 207  */
 208 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
 209                  void *cpu_addr, dma_addr_t handle, size_t size)
 210 {
 211         struct page *page = virt_to_page(cpu_addr);
 212         int ret;
 213
 214         ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
 215         if (unlikely(ret))
 216                 return ret;
 217
 218         sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
 219         return 0;
 220 }
 221 EXPORT_SYMBOL(dma_common_get_sgtable);
 222
 223 /*
 224  * Create userspace mapping for the DMA-coherent memory.
 225  */
 226 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
 227                     void *cpu_addr, dma_addr_t dma_addr, size_t size)
 228 {
 229         int ret = -ENXIO;
 230 #ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
 231         unsigned long user_count = vma_pages(vma);
 232         unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 233         unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
 234         unsigned long off = vma->vm_pgoff;
 235
 236         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 237
 238         if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
 239                 return ret;
 240
 241         if (off < count && user_count <= (count - off)) {
 242                 ret = remap_pfn_range(vma, vma->vm_start,
 243                                       pfn + off,
 244                                       user_count << PAGE_SHIFT,
 245                                       vma->vm_page_prot);
 246         }
 247 #endif  /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
 248
 249         return ret;
 250 }
 251 EXPORT_SYMBOL(dma_common_mmap);
 252
 253 #ifdef CONFIG_MMU
 254 static struct vm_struct *__dma_common_pages_remap(struct page **pages,
 255                         size_t size, unsigned long vm_flags, pgprot_t prot,
 256                         const void *caller)
 257 {
 258         struct vm_struct *area;
 259
 260         area = get_vm_area_caller(size, vm_flags, caller);
 261         if (!area)
 262                 return NULL;
 263
 264         if (map_vm_area(area, prot, pages)) {
 265                 vunmap(area->addr);
 266                 return NULL;
 267         }
 268
 269         return area;
 270 }
 271
 272 /*
 273  * remaps an array of PAGE_SIZE pages into another vm_area
 274  * Cannot be used in non-sleeping contexts
 275  */
 276 void *dma_common_pages_remap(struct page **pages, size_t size,
 277                         unsigned long vm_flags, pgprot_t prot,
 278                         const void *caller)
 279 {
 280         struct vm_struct *area;
 281
 282         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 283         if (!area)
 284                 return NULL;
 285
 286         area->pages = pages;
 287
 288         return area->addr;
 289 }
 290
 291 /*
 292  * remaps an allocated contiguous region into another vm_area.
 293  * Cannot be used in non-sleeping contexts
 294  */
 295
 296 void *dma_common_contiguous_remap(struct page *page, size_t size,
 297                         unsigned long vm_flags,
 298                         pgprot_t prot, const void *caller)
 299 {
 300         int i;
 301         struct page **pages;
 302         struct vm_struct *area;
 303
 304         pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
 305         if (!pages)
 306                 return NULL;
 307
 308         for (i = 0; i < (size >> PAGE_SHIFT); i++)
 309                 pages[i] = nth_page(page, i);
 310
 311         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 312
 313         kfree(pages);
 314
 315         if (!area)
 316                 return NULL;
 317         return area->addr;
 318 }
 319
 320 /*
 321  * unmaps a range previously mapped by dma_common_*_remap
 322  */
 323 void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
 324 {
 325         struct vm_struct *area = find_vm_area(cpu_addr);
 326
 327         if (!area || (area->flags & vm_flags) != vm_flags) {
 328                 WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
 329                 return;
 330         }
 331
 332         unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size));
 333         vunmap(cpu_addr);
 334 }
 335 #endif
 336
 337 /*
 338  * Common configuration to enable DMA API use for a device
 339  */
 340 #include <linux/pci.h>
 341
 342 int dma_configure(struct device *dev)
 343 {
 344         struct device *bridge = NULL, *dma_dev = dev;
 345         enum dev_dma_attr attr;
 346         int ret = 0;
 347
 348         if (dev_is_pci(dev)) {
 349                 bridge = pci_get_host_bridge_device(to_pci_dev(dev));
 350                 dma_dev = bridge;
 351                 if (IS_ENABLED(CONFIG_OF) && dma_dev->parent &&
 352                     dma_dev->parent->of_node)
 353                         dma_dev = dma_dev->parent;
 354         }
 355
 356         if (dma_dev->of_node) {
 357                 ret = of_dma_configure(dev, dma_dev->of_node);
 358         } else if (has_acpi_companion(dma_dev)) {
 359                 attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode));
 360                 if (attr != DEV_DMA_NOT_SUPPORTED)
 361                         ret = acpi_dma_configure(dev, attr);
 362         }
 363
 364         if (bridge)
 365                 pci_put_host_bridge_device(bridge);
 366
 367         return ret;
 368 }
 369
 370 void dma_deconfigure(struct device *dev)
 371 {
 372         of_dma_deconfigure(dev);
 373         acpi_dma_deconfigure(dev);
 374 }