kernel/dma/mapping.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * arch-independent dma-mapping routines
   4  *
   5  * Copyright (c) 2006  SUSE Linux Products GmbH
   6  * Copyright (c) 2006  Tejun Heo <teheo@suse.de>
   7  */
   8
   9 #include <linux/acpi.h>
  10 #include <linux/dma-mapping.h>
  11 #include <linux/export.h>
  12 #include <linux/gfp.h>
  13 #include <linux/of_device.h>
  14 #include <linux/slab.h>
  15 #include <linux/vmalloc.h>
  16
  17 /*
  18  * Managed DMA API
  19  */
  20 struct dma_devres {
  21         size_t          size;
  22         void            *vaddr;
  23         dma_addr_t      dma_handle;
  24         unsigned long   attrs;
  25 };
  26
  27 static void dmam_release(struct device *dev, void *res)
  28 {
  29         struct dma_devres *this = res;
  30
  31         dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,
  32                         this->attrs);
  33 }
  34
  35 static int dmam_match(struct device *dev, void *res, void *match_data)
  36 {
  37         struct dma_devres *this = res, *match = match_data;
  38
  39         if (this->vaddr == match->vaddr) {
  40                 WARN_ON(this->size != match->size ||
  41                         this->dma_handle != match->dma_handle);
  42                 return 1;
  43         }
  44         return 0;
  45 }
  46
  47 /**
  48  * dmam_alloc_coherent - Managed dma_alloc_coherent()
  49  * @dev: Device to allocate coherent memory for
  50  * @size: Size of allocation
  51  * @dma_handle: Out argument for allocated DMA handle
  52  * @gfp: Allocation flags
  53  *
  54  * Managed dma_alloc_coherent().  Memory allocated using this function
  55  * will be automatically released on driver detach.
  56  *
  57  * RETURNS:
  58  * Pointer to allocated memory on success, NULL on failure.
  59  */
  60 void *dmam_alloc_coherent(struct device *dev, size_t size,
  61                            dma_addr_t *dma_handle, gfp_t gfp)
  62 {
  63         struct dma_devres *dr;
  64         void *vaddr;
  65
  66         dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
  67         if (!dr)
  68                 return NULL;
  69
  70         vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
  71         if (!vaddr) {
  72                 devres_free(dr);
  73                 return NULL;
  74         }
  75
  76         dr->vaddr = vaddr;
  77         dr->dma_handle = *dma_handle;
  78         dr->size = size;
  79
  80         devres_add(dev, dr);
  81
  82         return vaddr;
  83 }
  84 EXPORT_SYMBOL(dmam_alloc_coherent);
  85
  86 /**
  87  * dmam_free_coherent - Managed dma_free_coherent()
  88  * @dev: Device to free coherent memory for
  89  * @size: Size of allocation
  90  * @vaddr: Virtual address of the memory to free
  91  * @dma_handle: DMA handle of the memory to free
  92  *
  93  * Managed dma_free_coherent().
  94  */
  95 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
  96                         dma_addr_t dma_handle)
  97 {
  98         struct dma_devres match_data = { size, vaddr, dma_handle };
  99
 100         dma_free_coherent(dev, size, vaddr, dma_handle);
 101         WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));
 102 }
 103 EXPORT_SYMBOL(dmam_free_coherent);
 104
 105 /**
 106  * dmam_alloc_attrs - Managed dma_alloc_attrs()
 107  * @dev: Device to allocate non_coherent memory for
 108  * @size: Size of allocation
 109  * @dma_handle: Out argument for allocated DMA handle
 110  * @gfp: Allocation flags
 111  * @attrs: Flags in the DMA_ATTR_* namespace.
 112  *
 113  * Managed dma_alloc_attrs().  Memory allocated using this function will be
 114  * automatically released on driver detach.
 115  *
 116  * RETURNS:
 117  * Pointer to allocated memory on success, NULL on failure.
 118  */
 119 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 120                 gfp_t gfp, unsigned long attrs)
 121 {
 122         struct dma_devres *dr;
 123         void *vaddr;
 124
 125         dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
 126         if (!dr)
 127                 return NULL;
 128
 129         vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
 130         if (!vaddr) {
 131                 devres_free(dr);
 132                 return NULL;
 133         }
 134
 135         dr->vaddr = vaddr;
 136         dr->dma_handle = *dma_handle;
 137         dr->size = size;
 138         dr->attrs = attrs;
 139
 140         devres_add(dev, dr);
 141
 142         return vaddr;
 143 }
 144 EXPORT_SYMBOL(dmam_alloc_attrs);
 145
 146 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
 147
 148 static void dmam_coherent_decl_release(struct device *dev, void *res)
 149 {
 150         dma_release_declared_memory(dev);
 151 }
 152
 153 /**
 154  * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
 155  * @dev: Device to declare coherent memory for
 156  * @phys_addr: Physical address of coherent memory to be declared
 157  * @device_addr: Device address of coherent memory to be declared
 158  * @size: Size of coherent memory to be declared
 159  * @flags: Flags
 160  *
 161  * Managed dma_declare_coherent_memory().
 162  *
 163  * RETURNS:
 164  * 0 on success, -errno on failure.
 165  */
 166 int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
 167                                  dma_addr_t device_addr, size_t size, int flags)
 168 {
 169         void *res;
 170         int rc;
 171
 172         res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
 173         if (!res)
 174                 return -ENOMEM;
 175
 176         rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
 177                                          flags);
 178         if (!rc)
 179                 devres_add(dev, res);
 180         else
 181                 devres_free(res);
 182
 183         return rc;
 184 }
 185 EXPORT_SYMBOL(dmam_declare_coherent_memory);
 186
 187 /**
 188  * dmam_release_declared_memory - Managed dma_release_declared_memory().
 189  * @dev: Device to release declared coherent memory for
 190  *
 191  * Managed dmam_release_declared_memory().
 192  */
 193 void dmam_release_declared_memory(struct device *dev)
 194 {
 195         WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
 196 }
 197 EXPORT_SYMBOL(dmam_release_declared_memory);
 198
 199 #endif
 200
 201 /*
 202  * Create scatter-list for the already allocated DMA buffer.
 203  */
 204 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
 205                  void *cpu_addr, dma_addr_t handle, size_t size)
 206 {
 207         struct page *page = virt_to_page(cpu_addr);
 208         int ret;
 209
 210         ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
 211         if (unlikely(ret))
 212                 return ret;
 213
 214         sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
 215         return 0;
 216 }
 217 EXPORT_SYMBOL(dma_common_get_sgtable);
 218
 219 /*
 220  * Create userspace mapping for the DMA-coherent memory.
 221  */
 222 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
 223                     void *cpu_addr, dma_addr_t dma_addr, size_t size)
 224 {
 225         int ret = -ENXIO;
 226 #ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
 227         unsigned long user_count = vma_pages(vma);
 228         unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 229         unsigned long off = vma->vm_pgoff;
 230
 231         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 232
 233         if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
 234                 return ret;
 235
 236         if (off < count && user_count <= (count - off))
 237                 ret = remap_pfn_range(vma, vma->vm_start,
 238                                       page_to_pfn(virt_to_page(cpu_addr)) + off,
 239                                       user_count << PAGE_SHIFT,
 240                                       vma->vm_page_prot);
 241 #endif  /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
 242
 243         return ret;
 244 }
 245 EXPORT_SYMBOL(dma_common_mmap);
 246
 247 #ifdef CONFIG_MMU
 248 static struct vm_struct *__dma_common_pages_remap(struct page **pages,
 249                         size_t size, unsigned long vm_flags, pgprot_t prot,
 250                         const void *caller)
 251 {
 252         struct vm_struct *area;
 253
 254         area = get_vm_area_caller(size, vm_flags, caller);
 255         if (!area)
 256                 return NULL;
 257
 258         if (map_vm_area(area, prot, pages)) {
 259                 vunmap(area->addr);
 260                 return NULL;
 261         }
 262
 263         return area;
 264 }
 265
 266 /*
 267  * remaps an array of PAGE_SIZE pages into another vm_area
 268  * Cannot be used in non-sleeping contexts
 269  */
 270 void *dma_common_pages_remap(struct page **pages, size_t size,
 271                         unsigned long vm_flags, pgprot_t prot,
 272                         const void *caller)
 273 {
 274         struct vm_struct *area;
 275
 276         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 277         if (!area)
 278                 return NULL;
 279
 280         area->pages = pages;
 281
 282         return area->addr;
 283 }
 284
 285 /*
 286  * remaps an allocated contiguous region into another vm_area.
 287  * Cannot be used in non-sleeping contexts
 288  */
 289
 290 void *dma_common_contiguous_remap(struct page *page, size_t size,
 291                         unsigned long vm_flags,
 292                         pgprot_t prot, const void *caller)
 293 {
 294         int i;
 295         struct page **pages;
 296         struct vm_struct *area;
 297
 298         pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
 299         if (!pages)
 300                 return NULL;
 301
 302         for (i = 0; i < (size >> PAGE_SHIFT); i++)
 303                 pages[i] = nth_page(page, i);
 304
 305         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 306
 307         kfree(pages);
 308
 309         if (!area)
 310                 return NULL;
 311         return area->addr;
 312 }
 313
 314 /*
 315  * unmaps a range previously mapped by dma_common_*_remap
 316  */
 317 void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
 318 {
 319         struct vm_struct *area = find_vm_area(cpu_addr);
 320
 321         if (!area || (area->flags & vm_flags) != vm_flags) {
 322                 WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
 323                 return;
 324         }
 325
 326         unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size));
 327         vunmap(cpu_addr);
 328 }
 329 #endif
 330
 331 /*
 332  * enables DMA API use for a device
 333  */
 334 int dma_configure(struct device *dev)
 335 {
 336         if (dev->bus->dma_configure)
 337                 return dev->bus->dma_configure(dev);
 338         return 0;
 339 }
 340
 341 void dma_deconfigure(struct device *dev)
 342 {
 343         of_dma_deconfigure(dev);
 344         acpi_dma_deconfigure(dev);
 345 }