release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/message/i2o/memory.c

   1 /*
   2  *      Functions to handle I2O memory
   3  *
   4  *      Pulled from the inlines in i2o headers and uninlined
   5  *
   6  *
   7  *      This program is free software; you can redistribute it and/or modify it
   8  *      under the terms of the GNU General Public License as published by the
   9  *      Free Software Foundation; either version 2 of the License, or (at your
  10  *      option) any later version.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/i2o.h>
  15 #include <linux/delay.h>
  16 #include <linux/string.h>
  17 #include <linux/slab.h>
  18 #include "core.h"
  19
  20 /* Protects our 32/64bit mask switching */
  21 static DEFINE_MUTEX(mem_lock);
  22
  23 /**
  24  *      i2o_sg_tablesize - Calculate the maximum number of elements in a SGL
  25  *      @c: I2O controller for which the calculation should be done
  26  *      @body_size: maximum body size used for message in 32-bit words.
  27  *
  28  *      Return the maximum number of SG elements in a SG list.
  29  */
  30 u16 i2o_sg_tablesize(struct i2o_controller *c, u16 body_size)
  31 {
  32         i2o_status_block *sb = c->status_block.virt;
  33         u16 sg_count =
  34             (sb->inbound_frame_size - sizeof(struct i2o_message) / 4) -
  35             body_size;
  36
  37         if (c->pae_support) {
  38                 /*
  39                  * for 64-bit a SG attribute element must be added and each
  40                  * SG element needs 12 bytes instead of 8.
  41                  */
  42                 sg_count -= 2;
  43                 sg_count /= 3;
  44         } else
  45                 sg_count /= 2;
  46
  47         if (c->short_req && (sg_count > 8))
  48                 sg_count = 8;
  49
  50         return sg_count;
  51 }
  52 EXPORT_SYMBOL_GPL(i2o_sg_tablesize);
  53
  54
  55 /**
  56  *      i2o_dma_map_single - Map pointer to controller and fill in I2O message.
  57  *      @c: I2O controller
  58  *      @ptr: pointer to the data which should be mapped
  59  *      @size: size of data in bytes
  60  *      @direction: DMA_TO_DEVICE / DMA_FROM_DEVICE
  61  *      @sg_ptr: pointer to the SG list inside the I2O message
  62  *
  63  *      This function does all necessary DMA handling and also writes the I2O
  64  *      SGL elements into the I2O message. For details on DMA handling see also
  65  *      dma_map_single(). The pointer sg_ptr will only be set to the end of the
  66  *      SG list if the allocation was successful.
  67  *
  68  *      Returns DMA address which must be checked for failures using
  69  *      dma_mapping_error().
  70  */
  71 dma_addr_t i2o_dma_map_single(struct i2o_controller *c, void *ptr,
  72                                             size_t size,
  73                                             enum dma_data_direction direction,
  74                                             u32 ** sg_ptr)
  75 {
  76         u32 sg_flags;
  77         u32 *mptr = *sg_ptr;
  78         dma_addr_t dma_addr;
  79
  80         switch (direction) {
  81         case DMA_TO_DEVICE:
  82                 sg_flags = 0xd4000000;
  83                 break;
  84         case DMA_FROM_DEVICE:
  85                 sg_flags = 0xd0000000;
  86                 break;
  87         default:
  88                 return 0;
  89         }
  90
  91         dma_addr = dma_map_single(&c->pdev->dev, ptr, size, direction);
  92         if (!dma_mapping_error(&c->pdev->dev, dma_addr)) {
  93 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
  94                 if ((sizeof(dma_addr_t) > 4) && c->pae_support) {
  95                         *mptr++ = cpu_to_le32(0x7C020002);
  96                         *mptr++ = cpu_to_le32(PAGE_SIZE);
  97                 }
  98 #endif
  99
 100                 *mptr++ = cpu_to_le32(sg_flags | size);
 101                 *mptr++ = cpu_to_le32(i2o_dma_low(dma_addr));
 102 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
 103                 if ((sizeof(dma_addr_t) > 4) && c->pae_support)
 104                         *mptr++ = cpu_to_le32(i2o_dma_high(dma_addr));
 105 #endif
 106                 *sg_ptr = mptr;
 107         }
 108         return dma_addr;
 109 }
 110 EXPORT_SYMBOL_GPL(i2o_dma_map_single);
 111
 112 /**
 113  *      i2o_dma_map_sg - Map a SG List to controller and fill in I2O message.
 114  *      @c: I2O controller
 115  *      @sg: SG list to be mapped
 116  *      @sg_count: number of elements in the SG list
 117  *      @direction: DMA_TO_DEVICE / DMA_FROM_DEVICE
 118  *      @sg_ptr: pointer to the SG list inside the I2O message
 119  *
 120  *      This function does all necessary DMA handling and also writes the I2O
 121  *      SGL elements into the I2O message. For details on DMA handling see also
 122  *      dma_map_sg(). The pointer sg_ptr will only be set to the end of the SG
 123  *      list if the allocation was successful.
 124  *
 125  *      Returns 0 on failure or 1 on success.
 126  */
 127 int i2o_dma_map_sg(struct i2o_controller *c, struct scatterlist *sg,
 128             int sg_count, enum dma_data_direction direction, u32 ** sg_ptr)
 129 {
 130         u32 sg_flags;
 131         u32 *mptr = *sg_ptr;
 132
 133         switch (direction) {
 134         case DMA_TO_DEVICE:
 135                 sg_flags = 0x14000000;
 136                 break;
 137         case DMA_FROM_DEVICE:
 138                 sg_flags = 0x10000000;
 139                 break;
 140         default:
 141                 return 0;
 142         }
 143
 144         sg_count = dma_map_sg(&c->pdev->dev, sg, sg_count, direction);
 145         if (!sg_count)
 146                 return 0;
 147
 148 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
 149         if ((sizeof(dma_addr_t) > 4) && c->pae_support) {
 150                 *mptr++ = cpu_to_le32(0x7C020002);
 151                 *mptr++ = cpu_to_le32(PAGE_SIZE);
 152         }
 153 #endif
 154
 155         while (sg_count-- > 0) {
 156                 if (!sg_count)
 157                         sg_flags |= 0xC0000000;
 158                 *mptr++ = cpu_to_le32(sg_flags | sg_dma_len(sg));
 159                 *mptr++ = cpu_to_le32(i2o_dma_low(sg_dma_address(sg)));
 160 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
 161                 if ((sizeof(dma_addr_t) > 4) && c->pae_support)
 162                         *mptr++ = cpu_to_le32(i2o_dma_high(sg_dma_address(sg)));
 163 #endif
 164                 sg = sg_next(sg);
 165         }
 166         *sg_ptr = mptr;
 167
 168         return 1;
 169 }
 170 EXPORT_SYMBOL_GPL(i2o_dma_map_sg);
 171
 172 /**
 173  *      i2o_dma_alloc - Allocate DMA memory
 174  *      @dev: struct device pointer to the PCI device of the I2O controller
 175  *      @addr: i2o_dma struct which should get the DMA buffer
 176  *      @len: length of the new DMA memory
 177  *
 178  *      Allocate a coherent DMA memory and write the pointers into addr.
 179  *
 180  *      Returns 0 on success or -ENOMEM on failure.
 181  */
 182 int i2o_dma_alloc(struct device *dev, struct i2o_dma *addr, size_t len)
 183 {
 184         struct pci_dev *pdev = to_pci_dev(dev);
 185         int dma_64 = 0;
 186
 187         mutex_lock(&mem_lock);
 188         if ((sizeof(dma_addr_t) > 4) && (pdev->dma_mask == DMA_BIT_MASK(64))) {
 189                 dma_64 = 1;
 190                 if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
 191                         mutex_unlock(&mem_lock);
 192                         return -ENOMEM;
 193                 }
 194         }
 195
 196         addr->virt = dma_alloc_coherent(dev, len, &addr->phys, GFP_KERNEL);
 197
 198         if ((sizeof(dma_addr_t) > 4) && dma_64)
 199                 if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64)))
 200                         printk(KERN_WARNING "i2o: unable to set 64-bit DMA");
 201         mutex_unlock(&mem_lock);
 202
 203         if (!addr->virt)
 204                 return -ENOMEM;
 205
 206         memset(addr->virt, 0, len);
 207         addr->len = len;
 208
 209         return 0;
 210 }
 211 EXPORT_SYMBOL_GPL(i2o_dma_alloc);
 212
 213
 214 /**
 215  *      i2o_dma_free - Free DMA memory
 216  *      @dev: struct device pointer to the PCI device of the I2O controller
 217  *      @addr: i2o_dma struct which contains the DMA buffer
 218  *
 219  *      Free a coherent DMA memory and set virtual address of addr to NULL.
 220  */
 221 void i2o_dma_free(struct device *dev, struct i2o_dma *addr)
 222 {
 223         if (addr->virt) {
 224                 if (addr->phys)
 225                         dma_free_coherent(dev, addr->len, addr->virt,
 226                                           addr->phys);
 227                 else
 228                         kfree(addr->virt);
 229                 addr->virt = NULL;
 230         }
 231 }
 232 EXPORT_SYMBOL_GPL(i2o_dma_free);
 233
 234
 235 /**
 236  *      i2o_dma_realloc - Realloc DMA memory
 237  *      @dev: struct device pointer to the PCI device of the I2O controller
 238  *      @addr: pointer to a i2o_dma struct DMA buffer
 239  *      @len: new length of memory
 240  *
 241  *      If there was something allocated in the addr, free it first. If len > 0
 242  *      than try to allocate it and write the addresses back to the addr
 243  *      structure. If len == 0 set the virtual address to NULL.
 244  *
 245  *      Returns the 0 on success or negative error code on failure.
 246  */
 247 int i2o_dma_realloc(struct device *dev, struct i2o_dma *addr, size_t len)
 248 {
 249         i2o_dma_free(dev, addr);
 250
 251         if (len)
 252                 return i2o_dma_alloc(dev, addr, len);
 253
 254         return 0;
 255 }
 256 EXPORT_SYMBOL_GPL(i2o_dma_realloc);
 257
 258 /*
 259  *      i2o_pool_alloc - Allocate an slab cache and mempool
 260  *      @mempool: pointer to struct i2o_pool to write data into.
 261  *      @name: name which is used to identify cache
 262  *      @size: size of each object
 263  *      @min_nr: minimum number of objects
 264  *
 265  *      First allocates a slab cache with name and size. Then allocates a
 266  *      mempool which uses the slab cache for allocation and freeing.
 267  *
 268  *      Returns 0 on success or negative error code on failure.
 269  */
 270 int i2o_pool_alloc(struct i2o_pool *pool, const char *name,
 271                                  size_t size, int min_nr)
 272 {
 273         pool->name = kmalloc(strlen(name) + 1, GFP_KERNEL);
 274         if (!pool->name)
 275                 goto exit;
 276         strcpy(pool->name, name);
 277
 278         pool->slab =
 279             kmem_cache_create(pool->name, size, 0, SLAB_HWCACHE_ALIGN, NULL);
 280         if (!pool->slab)
 281                 goto free_name;
 282
 283         pool->mempool = mempool_create_slab_pool(min_nr, pool->slab);
 284         if (!pool->mempool)
 285                 goto free_slab;
 286
 287         return 0;
 288
 289 free_slab:
 290         kmem_cache_destroy(pool->slab);
 291
 292 free_name:
 293         kfree(pool->name);
 294
 295 exit:
 296         return -ENOMEM;
 297 }
 298 EXPORT_SYMBOL_GPL(i2o_pool_alloc);
 299
 300 /*
 301  *      i2o_pool_free - Free slab cache and mempool again
 302  *      @mempool: pointer to struct i2o_pool which should be freed
 303  *
 304  *      Note that you have to return all objects to the mempool again before
 305  *      calling i2o_pool_free().
 306  */
 307 void i2o_pool_free(struct i2o_pool *pool)
 308 {
 309         mempool_destroy(pool->mempool);
 310         kmem_cache_destroy(pool->slab);
 311         kfree(pool->name);
 312 };
 313 EXPORT_SYMBOL_GPL(i2o_pool_free);