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-noncoherent.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 dma_addr, size_t size,
 206                  unsigned long attrs)
 207 {
 208         struct page *page;
 209         int ret;
 210
 211         if (!dev_is_dma_coherent(dev)) {
 212                 if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))
 213                         return -ENXIO;
 214
 215                 page = pfn_to_page(arch_dma_coherent_to_pfn(dev, cpu_addr,
 216                                 dma_addr));
 217         } else {
 218                 page = virt_to_page(cpu_addr);
 219         }
 220
 221         ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
 222         if (!ret)
 223                 sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
 224         return ret;
 225 }
 226 EXPORT_SYMBOL(dma_common_get_sgtable);
 227
 228 /*
 229  * Create userspace mapping for the DMA-coherent memory.
 230  */
 231 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
 232                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
 233                 unsigned long attrs)
 234 {
 235 #ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
 236         unsigned long user_count = vma_pages(vma);
 237         unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 238         unsigned long off = vma->vm_pgoff;
 239         unsigned long pfn;
 240         int ret = -ENXIO;
 241
 242         vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs);
 243
 244         if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
 245                 return ret;
 246
 247         if (off >= count || user_count > count - off)
 248                 return -ENXIO;
 249
 250         if (!dev_is_dma_coherent(dev)) {
 251                 if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))
 252                         return -ENXIO;
 253                 pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr);
 254         } else {
 255                 pfn = page_to_pfn(virt_to_page(cpu_addr));
 256         }
 257
 258         return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
 259                         user_count << PAGE_SHIFT, vma->vm_page_prot);
 260 #else
 261         return -ENXIO;
 262 #endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
 263 }
 264 EXPORT_SYMBOL(dma_common_mmap);
 265
 266 #ifdef CONFIG_MMU
 267 static struct vm_struct *__dma_common_pages_remap(struct page **pages,
 268                         size_t size, unsigned long vm_flags, pgprot_t prot,
 269                         const void *caller)
 270 {
 271         struct vm_struct *area;
 272
 273         area = get_vm_area_caller(size, vm_flags, caller);
 274         if (!area)
 275                 return NULL;
 276
 277         if (map_vm_area(area, prot, pages)) {
 278                 vunmap(area->addr);
 279                 return NULL;
 280         }
 281
 282         return area;
 283 }
 284
 285 /*
 286  * remaps an array of PAGE_SIZE pages into another vm_area
 287  * Cannot be used in non-sleeping contexts
 288  */
 289 void *dma_common_pages_remap(struct page **pages, size_t size,
 290                         unsigned long vm_flags, pgprot_t prot,
 291                         const void *caller)
 292 {
 293         struct vm_struct *area;
 294
 295         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 296         if (!area)
 297                 return NULL;
 298
 299         area->pages = pages;
 300
 301         return area->addr;
 302 }
 303
 304 /*
 305  * remaps an allocated contiguous region into another vm_area.
 306  * Cannot be used in non-sleeping contexts
 307  */
 308
 309 void *dma_common_contiguous_remap(struct page *page, size_t size,
 310                         unsigned long vm_flags,
 311                         pgprot_t prot, const void *caller)
 312 {
 313         int i;
 314         struct page **pages;
 315         struct vm_struct *area;
 316
 317         pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
 318         if (!pages)
 319                 return NULL;
 320
 321         for (i = 0; i < (size >> PAGE_SHIFT); i++)
 322                 pages[i] = nth_page(page, i);
 323
 324         area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
 325
 326         kfree(pages);
 327
 328         if (!area)
 329                 return NULL;
 330         return area->addr;
 331 }
 332
 333 /*
 334  * unmaps a range previously mapped by dma_common_*_remap
 335  */
 336 void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
 337 {
 338         struct vm_struct *area = find_vm_area(cpu_addr);
 339
 340         if (!area || (area->flags & vm_flags) != vm_flags) {
 341                 WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
 342                 return;
 343         }
 344
 345         unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size));
 346         vunmap(cpu_addr);
 347 }
 348 #endif