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/dma-mapping.h>
  11 #include <linux/export.h>
  12 #include <linux/gfp.h>
  13
  14 /*
  15  * Managed DMA API
  16  */
  17 struct dma_devres {
  18         size_t          size;
  19         void            *vaddr;
  20         dma_addr_t      dma_handle;
  21 };
  22
  23 static void dmam_coherent_release(struct device *dev, void *res)
  24 {
  25         struct dma_devres *this = res;
  26
  27         dma_free_coherent(dev, this->size, this->vaddr, this->dma_handle);
  28 }
  29
  30 static void dmam_noncoherent_release(struct device *dev, void *res)
  31 {
  32         struct dma_devres *this = res;
  33
  34         dma_free_noncoherent(dev, this->size, this->vaddr, this->dma_handle);
  35 }
  36
  37 static int dmam_match(struct device *dev, void *res, void *match_data)
  38 {
  39         struct dma_devres *this = res, *match = match_data;
  40
  41         if (this->vaddr == match->vaddr) {
  42                 WARN_ON(this->size != match->size ||
  43                         this->dma_handle != match->dma_handle);
  44                 return 1;
  45         }
  46         return 0;
  47 }
  48
  49 /**
  50  * dmam_alloc_coherent - Managed dma_alloc_coherent()
  51  * @dev: Device to allocate coherent memory for
  52  * @size: Size of allocation
  53  * @dma_handle: Out argument for allocated DMA handle
  54  * @gfp: Allocation flags
  55  *
  56  * Managed dma_alloc_coherent().  Memory allocated using this function
  57  * will be automatically released on driver detach.
  58  *
  59  * RETURNS:
  60  * Pointer to allocated memory on success, NULL on failure.
  61  */
  62 void * dmam_alloc_coherent(struct device *dev, size_t size,
  63                            dma_addr_t *dma_handle, gfp_t gfp)
  64 {
  65         struct dma_devres *dr;
  66         void *vaddr;
  67
  68         dr = devres_alloc(dmam_coherent_release, sizeof(*dr), gfp);
  69         if (!dr)
  70                 return NULL;
  71
  72         vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
  73         if (!vaddr) {
  74                 devres_free(dr);
  75                 return NULL;
  76         }
  77
  78         dr->vaddr = vaddr;
  79         dr->dma_handle = *dma_handle;
  80         dr->size = size;
  81
  82         devres_add(dev, dr);
  83
  84         return vaddr;
  85 }
  86 EXPORT_SYMBOL(dmam_alloc_coherent);
  87
  88 /**
  89  * dmam_free_coherent - Managed dma_free_coherent()
  90  * @dev: Device to free coherent memory for
  91  * @size: Size of allocation
  92  * @vaddr: Virtual address of the memory to free
  93  * @dma_handle: DMA handle of the memory to free
  94  *
  95  * Managed dma_free_coherent().
  96  */
  97 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
  98                         dma_addr_t dma_handle)
  99 {
 100         struct dma_devres match_data = { size, vaddr, dma_handle };
 101
 102         dma_free_coherent(dev, size, vaddr, dma_handle);
 103         WARN_ON(devres_destroy(dev, dmam_coherent_release, dmam_match,
 104                                &match_data));
 105 }
 106 EXPORT_SYMBOL(dmam_free_coherent);
 107
 108 /**
 109  * dmam_alloc_non_coherent - Managed dma_alloc_non_coherent()
 110  * @dev: Device to allocate non_coherent memory for
 111  * @size: Size of allocation
 112  * @dma_handle: Out argument for allocated DMA handle
 113  * @gfp: Allocation flags
 114  *
 115  * Managed dma_alloc_non_coherent().  Memory allocated using this
 116  * function will be automatically released on driver detach.
 117  *
 118  * RETURNS:
 119  * Pointer to allocated memory on success, NULL on failure.
 120  */
 121 void *dmam_alloc_noncoherent(struct device *dev, size_t size,
 122                              dma_addr_t *dma_handle, gfp_t gfp)
 123 {
 124         struct dma_devres *dr;
 125         void *vaddr;
 126
 127         dr = devres_alloc(dmam_noncoherent_release, sizeof(*dr), gfp);
 128         if (!dr)
 129                 return NULL;
 130
 131         vaddr = dma_alloc_noncoherent(dev, size, dma_handle, gfp);
 132         if (!vaddr) {
 133                 devres_free(dr);
 134                 return NULL;
 135         }
 136
 137         dr->vaddr = vaddr;
 138         dr->dma_handle = *dma_handle;
 139         dr->size = size;
 140
 141         devres_add(dev, dr);
 142
 143         return vaddr;
 144 }
 145 EXPORT_SYMBOL(dmam_alloc_noncoherent);
 146
 147 /**
 148  * dmam_free_coherent - Managed dma_free_noncoherent()
 149  * @dev: Device to free noncoherent memory for
 150  * @size: Size of allocation
 151  * @vaddr: Virtual address of the memory to free
 152  * @dma_handle: DMA handle of the memory to free
 153  *
 154  * Managed dma_free_noncoherent().
 155  */
 156 void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 157                            dma_addr_t dma_handle)
 158 {
 159         struct dma_devres match_data = { size, vaddr, dma_handle };
 160
 161         dma_free_noncoherent(dev, size, vaddr, dma_handle);
 162         WARN_ON(!devres_destroy(dev, dmam_noncoherent_release, dmam_match,
 163                                 &match_data));
 164 }
 165 EXPORT_SYMBOL(dmam_free_noncoherent);
 166
 167 #ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
 168
 169 static void dmam_coherent_decl_release(struct device *dev, void *res)
 170 {
 171         dma_release_declared_memory(dev);
 172 }
 173
 174 /**
 175  * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
 176  * @dev: Device to declare coherent memory for
 177  * @bus_addr: Bus address of coherent memory to be declared
 178  * @device_addr: Device address of coherent memory to be declared
 179  * @size: Size of coherent memory to be declared
 180  * @flags: Flags
 181  *
 182  * Managed dma_declare_coherent_memory().
 183  *
 184  * RETURNS:
 185  * 0 on success, -errno on failure.
 186  */
 187 int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
 188                                  dma_addr_t device_addr, size_t size, int flags)
 189 {
 190         void *res;
 191         int rc;
 192
 193         res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
 194         if (!res)
 195                 return -ENOMEM;
 196
 197         rc = dma_declare_coherent_memory(dev, bus_addr, device_addr, size,
 198                                          flags);
 199         if (rc == 0)
 200                 devres_add(dev, res);
 201         else
 202                 devres_free(res);
 203
 204         return rc;
 205 }
 206 EXPORT_SYMBOL(dmam_declare_coherent_memory);
 207
 208 /**
 209  * dmam_release_declared_memory - Managed dma_release_declared_memory().
 210  * @dev: Device to release declared coherent memory for
 211  *
 212  * Managed dmam_release_declared_memory().
 213  */
 214 void dmam_release_declared_memory(struct device *dev)
 215 {
 216         WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
 217 }
 218 EXPORT_SYMBOL(dmam_release_declared_memory);
 219
 220 #endif