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         else
 182                 devres_free(res);
 183
 184         return rc;
 185 }
 186 EXPORT_SYMBOL(dmam_declare_coherent_memory);
 187
 188 /**
 189  * dmam_release_declared_memory - Managed dma_release_declared_memory().
 190  * @dev: Device to release declared coherent memory for
 191  *
 192  * Managed dmam_release_declared_memory().
 193  */
 194 void dmam_release_declared_memory(struct device *dev)
 195 {
 196         WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
 197 }
 198 EXPORT_SYMBOL(dmam_release_declared_memory);
 199
 200 #endif
 201
 202 /*
 203  * Create scatter-list for the already allocated DMA buffer.
 204  */
 205 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
 206                  void *cpu_addr, dma_addr_t handle, size_t size)
 207 {
 208         struct page *page = virt_to_page(cpu_addr);
 209         int ret;
 210
 211         ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
 212         if (unlikely(ret))
 213                 return ret;
 214
 215         sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
 216         return 0;
 217 }
 218 EXPORT_SYMBOL(dma_common_get_sgtable);
 219
 220 /*
 221  * Create userspace mapping for the DMA-coherent memory.
 222  */
 223 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
 224                     void *cpu_addr, dma_addr_t dma_addr, size_t size)
 225 {
 226         int ret = -ENXIO;
 227 #ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
 228         unsigned long user_count = vma_pages(vma);
 229         unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 230         unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
 231         unsigned long off = vma->vm_pgoff;
 232
 233         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 234
 235         if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
 236                 return ret;
 237
 238         if (off < count && user_count <= (count - off)) {
 239                 ret = remap_pfn_range(vma, vma->vm_start,
 240                                       pfn + off,
 241                                       user_count << PAGE_SHIFT,
 242                                       vma->vm_page_prot);
 243         }
 244 #endif  /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
 245
 246         return ret;
 247 }
 248 EXPORT_SYMBOL(dma_common_mmap);
 249
 250 #ifdef CONFIG_MMU
 251 static struct vm_struct *__dma_common_pages_remap(struct page **pages,
 252                         size_t size, unsigned long vm_flags, pgprot_t prot,
 253                         const void *caller)
 254 {
 255         struct vm_struct *area;
 256
 257         area = get_vm_area_caller(size, vm_flags, caller);
 258         if (!area)
 259                 return NULL;
 260
 261         if (map_vm_area(area, prot, pages)) {
 262                 vunmap(area->addr);
 263                 return NULL;
 264         }
 265
 266         return area;
 267 }
 268
 269 /*
 270  * remaps an array of PAGE_SIZE pages into another vm_area
 271  * Cannot be used in non-sleeping contexts
 272  */
 273 void *dma_common_pages_remap(struct page **pages, size_t size,
 274                         unsigned long vm_flags, pgprot_t prot,
 275                         const void *caller)
 276 {
 277         struct vm_struct *area;
 278
 279         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 280         if (!area)
 281                 return NULL;
 282
 283         area->pages = pages;
 284
 285         return area->addr;
 286 }
 287
 288 /*
 289  * remaps an allocated contiguous region into another vm_area.
 290  * Cannot be used in non-sleeping contexts
 291  */
 292
 293 void *dma_common_contiguous_remap(struct page *page, size_t size,
 294                         unsigned long vm_flags,
 295                         pgprot_t prot, const void *caller)
 296 {
 297         int i;
 298         struct page **pages;
 299         struct vm_struct *area;
 300
 301         pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
 302         if (!pages)
 303                 return NULL;
 304
 305         for (i = 0; i < (size >> PAGE_SHIFT); i++)
 306                 pages[i] = nth_page(page, i);
 307
 308         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 309
 310         kfree(pages);
 311
 312         if (!area)
 313                 return NULL;
 314         return area->addr;
 315 }
 316
 317 /*
 318  * unmaps a range previously mapped by dma_common_*_remap
 319  */
 320 void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
 321 {
 322         struct vm_struct *area = find_vm_area(cpu_addr);
 323
 324         if (!area || (area->flags & vm_flags) != vm_flags) {
 325                 WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
 326                 return;
 327         }
 328
 329         unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size));
 330         vunmap(cpu_addr);
 331 }
 332 #endif
 333
 334 /*
 335  * Common configuration to enable DMA API use for a device
 336  */
 337 #include <linux/pci.h>
 338
 339 int dma_configure(struct device *dev)
 340 {
 341         struct device *bridge = NULL, *dma_dev = dev;
 342         enum dev_dma_attr attr;
 343         int ret = 0;
 344
 345         if (dev_is_pci(dev)) {
 346                 bridge = pci_get_host_bridge_device(to_pci_dev(dev));
 347                 dma_dev = bridge;
 348                 if (IS_ENABLED(CONFIG_OF) && dma_dev->parent &&
 349                     dma_dev->parent->of_node)
 350                         dma_dev = dma_dev->parent;
 351         }
 352
 353         if (dma_dev->of_node) {
 354                 ret = of_dma_configure(dev, dma_dev->of_node);
 355         } else if (has_acpi_companion(dma_dev)) {
 356                 attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode));
 357                 if (attr != DEV_DMA_NOT_SUPPORTED)
 358                         ret = acpi_dma_configure(dev, attr);
 359         }
 360
 361         if (bridge)
 362                 pci_put_host_bridge_device(bridge);
 363
 364         return ret;
 365 }
 366
 367 void dma_deconfigure(struct device *dev)
 368 {
 369         of_dma_deconfigure(dev);
 370         acpi_dma_deconfigure(dev);
 371 }