drivers/char/ps3flash.c

   1 /*
   2  * PS3 FLASH ROM Storage Driver
   3  *
   4  * Copyright (C) 2007 Sony Computer Entertainment Inc.
   5  * Copyright 2007 Sony Corp.
   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
   9  * by the Free Software Foundation; version 2 of the License.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include <linux/fs.h>
  22 #include <linux/miscdevice.h>
  23 #include <linux/slab.h>
  24 #include <linux/uaccess.h>
  25 #include <linux/module.h>
  26
  27 #include <asm/lv1call.h>
  28 #include <asm/ps3stor.h>
  29
  30
  31 #define DEVICE_NAME             "ps3flash"
  32
  33 #define FLASH_BLOCK_SIZE        (256*1024)
  34
  35
  36 struct ps3flash_private {
  37         struct mutex mutex;     /* Bounce buffer mutex */
  38         u64 chunk_sectors;
  39         int tag;                /* Start sector of buffer, -1 if invalid */
  40         bool dirty;
  41 };
  42
  43 static struct ps3_storage_device *ps3flash_dev;
  44
  45 static int ps3flash_read_write_sectors(struct ps3_storage_device *dev,
  46                                        u64 start_sector, int write)
  47 {
  48         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
  49         u64 res = ps3stor_read_write_sectors(dev, dev->bounce_lpar,
  50                                              start_sector, priv->chunk_sectors,
  51                                              write);
  52         if (res) {
  53                 dev_err(&dev->sbd.core, "%s:%u: %s failed 0x%llx\n", __func__,
  54                         __LINE__, write ? "write" : "read", res);
  55                 return -EIO;
  56         }
  57         return 0;
  58 }
  59
  60 static int ps3flash_writeback(struct ps3_storage_device *dev)
  61 {
  62         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
  63         int res;
  64
  65         if (!priv->dirty || priv->tag < 0)
  66                 return 0;
  67
  68         res = ps3flash_read_write_sectors(dev, priv->tag, 1);
  69         if (res)
  70                 return res;
  71
  72         priv->dirty = false;
  73         return 0;
  74 }
  75
  76 static int ps3flash_fetch(struct ps3_storage_device *dev, u64 start_sector)
  77 {
  78         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
  79         int res;
  80
  81         if (start_sector == priv->tag)
  82                 return 0;
  83
  84         res = ps3flash_writeback(dev);
  85         if (res)
  86                 return res;
  87
  88         priv->tag = -1;
  89
  90         res = ps3flash_read_write_sectors(dev, start_sector, 0);
  91         if (res)
  92                 return res;
  93
  94         priv->tag = start_sector;
  95         return 0;
  96 }
  97
  98 static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
  99 {
 100         struct ps3_storage_device *dev = ps3flash_dev;
 101         loff_t res;
 102
 103         mutex_lock(&file->f_mapping->host->i_mutex);
 104         switch (origin) {
 105         case 0:
 106                 break;
 107         case 1:
 108                 offset += file->f_pos;
 109                 break;
 110         case 2:
 111                 offset += dev->regions[dev->region_idx].size*dev->blk_size;
 112                 break;
 113         default:
 114                 offset = -1;
 115         }
 116         if (offset < 0) {
 117                 res = -EINVAL;
 118                 goto out;
 119         }
 120
 121         file->f_pos = offset;
 122         res = file->f_pos;
 123
 124 out:
 125         mutex_unlock(&file->f_mapping->host->i_mutex);
 126         return res;
 127 }
 128
 129 static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
 130                              size_t count, loff_t *pos)
 131 {
 132         struct ps3_storage_device *dev = ps3flash_dev;
 133         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
 134         u64 size, sector, offset;
 135         int res;
 136         size_t remaining, n;
 137         const void *src;
 138
 139         dev_dbg(&dev->sbd.core,
 140                 "%s:%u: Reading %zu bytes at position %lld to U0x%p/K0x%p\n",
 141                 __func__, __LINE__, count, *pos, userbuf, kernelbuf);
 142
 143         size = dev->regions[dev->region_idx].size*dev->blk_size;
 144         if (*pos >= size || !count)
 145                 return 0;
 146
 147         if (*pos + count > size) {
 148                 dev_dbg(&dev->sbd.core,
 149                         "%s:%u Truncating count from %zu to %llu\n", __func__,
 150                         __LINE__, count, size - *pos);
 151                 count = size - *pos;
 152         }
 153
 154         sector = *pos / dev->bounce_size * priv->chunk_sectors;
 155         offset = *pos % dev->bounce_size;
 156
 157         remaining = count;
 158         do {
 159                 n = min_t(u64, remaining, dev->bounce_size - offset);
 160                 src = dev->bounce_buf + offset;
 161
 162                 mutex_lock(&priv->mutex);
 163
 164                 res = ps3flash_fetch(dev, sector);
 165                 if (res)
 166                         goto fail;
 167
 168                 dev_dbg(&dev->sbd.core,
 169                         "%s:%u: copy %lu bytes from 0x%p to U0x%p/K0x%p\n",
 170                         __func__, __LINE__, n, src, userbuf, kernelbuf);
 171                 if (userbuf) {
 172                         if (copy_to_user(userbuf, src, n)) {
 173                                 res = -EFAULT;
 174                                 goto fail;
 175                         }
 176                         userbuf += n;
 177                 }
 178                 if (kernelbuf) {
 179                         memcpy(kernelbuf, src, n);
 180                         kernelbuf += n;
 181                 }
 182
 183                 mutex_unlock(&priv->mutex);
 184
 185                 *pos += n;
 186                 remaining -= n;
 187                 sector += priv->chunk_sectors;
 188                 offset = 0;
 189         } while (remaining > 0);
 190
 191         return count;
 192
 193 fail:
 194         mutex_unlock(&priv->mutex);
 195         return res;
 196 }
 197
 198 static ssize_t ps3flash_write(const char __user *userbuf,
 199                               const void *kernelbuf, size_t count, loff_t *pos)
 200 {
 201         struct ps3_storage_device *dev = ps3flash_dev;
 202         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
 203         u64 size, sector, offset;
 204         int res = 0;
 205         size_t remaining, n;
 206         void *dst;
 207
 208         dev_dbg(&dev->sbd.core,
 209                 "%s:%u: Writing %zu bytes at position %lld from U0x%p/K0x%p\n",
 210                 __func__, __LINE__, count, *pos, userbuf, kernelbuf);
 211
 212         size = dev->regions[dev->region_idx].size*dev->blk_size;
 213         if (*pos >= size || !count)
 214                 return 0;
 215
 216         if (*pos + count > size) {
 217                 dev_dbg(&dev->sbd.core,
 218                         "%s:%u Truncating count from %zu to %llu\n", __func__,
 219                         __LINE__, count, size - *pos);
 220                 count = size - *pos;
 221         }
 222
 223         sector = *pos / dev->bounce_size * priv->chunk_sectors;
 224         offset = *pos % dev->bounce_size;
 225
 226         remaining = count;
 227         do {
 228                 n = min_t(u64, remaining, dev->bounce_size - offset);
 229                 dst = dev->bounce_buf + offset;
 230
 231                 mutex_lock(&priv->mutex);
 232
 233                 if (n != dev->bounce_size)
 234                         res = ps3flash_fetch(dev, sector);
 235                 else if (sector != priv->tag)
 236                         res = ps3flash_writeback(dev);
 237                 if (res)
 238                         goto fail;
 239
 240                 dev_dbg(&dev->sbd.core,
 241                         "%s:%u: copy %lu bytes from U0x%p/K0x%p to 0x%p\n",
 242                         __func__, __LINE__, n, userbuf, kernelbuf, dst);
 243                 if (userbuf) {
 244                         if (copy_from_user(dst, userbuf, n)) {
 245                                 res = -EFAULT;
 246                                 goto fail;
 247                         }
 248                         userbuf += n;
 249                 }
 250                 if (kernelbuf) {
 251                         memcpy(dst, kernelbuf, n);
 252                         kernelbuf += n;
 253                 }
 254
 255                 priv->tag = sector;
 256                 priv->dirty = true;
 257
 258                 mutex_unlock(&priv->mutex);
 259
 260                 *pos += n;
 261                 remaining -= n;
 262                 sector += priv->chunk_sectors;
 263                 offset = 0;
 264         } while (remaining > 0);
 265
 266         return count;
 267
 268 fail:
 269         mutex_unlock(&priv->mutex);
 270         return res;
 271 }
 272
 273 static ssize_t ps3flash_user_read(struct file *file, char __user *buf,
 274                                   size_t count, loff_t *pos)
 275 {
 276         return ps3flash_read(buf, NULL, count, pos);
 277 }
 278
 279 static ssize_t ps3flash_user_write(struct file *file, const char __user *buf,
 280                                    size_t count, loff_t *pos)
 281 {
 282         return ps3flash_write(buf, NULL, count, pos);
 283 }
 284
 285 static ssize_t ps3flash_kernel_read(void *buf, size_t count, loff_t pos)
 286 {
 287         return ps3flash_read(NULL, buf, count, &pos);
 288 }
 289
 290 static ssize_t ps3flash_kernel_write(const void *buf, size_t count,
 291                                      loff_t pos)
 292 {
 293         ssize_t res;
 294         int wb;
 295
 296         res = ps3flash_write(NULL, buf, count, &pos);
 297         if (res < 0)
 298                 return res;
 299
 300         /* Make kernel writes synchronous */
 301         wb = ps3flash_writeback(ps3flash_dev);
 302         if (wb)
 303                 return wb;
 304
 305         return res;
 306 }
 307
 308 static int ps3flash_flush(struct file *file, fl_owner_t id)
 309 {
 310         return ps3flash_writeback(ps3flash_dev);
 311 }
 312
 313 static int ps3flash_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 314 {
 315         struct inode *inode = file->f_path.dentry->d_inode;
 316         int err;
 317         mutex_lock(&inode->i_mutex);
 318         err = ps3flash_writeback(ps3flash_dev);
 319         mutex_unlock(&inode->i_mutex);
 320         return err;
 321 }
 322
 323 static irqreturn_t ps3flash_interrupt(int irq, void *data)
 324 {
 325         struct ps3_storage_device *dev = data;
 326         int res;
 327         u64 tag, status;
 328
 329         res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
 330
 331         if (tag != dev->tag)
 332                 dev_err(&dev->sbd.core,
 333                         "%s:%u: tag mismatch, got %llx, expected %llx\n",
 334                         __func__, __LINE__, tag, dev->tag);
 335
 336         if (res) {
 337                 dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%llx\n",
 338                         __func__, __LINE__, res, status);
 339         } else {
 340                 dev->lv1_status = status;
 341                 complete(&dev->done);
 342         }
 343         return IRQ_HANDLED;
 344 }
 345
 346 static const struct file_operations ps3flash_fops = {
 347         .owner  = THIS_MODULE,
 348         .llseek = ps3flash_llseek,
 349         .read   = ps3flash_user_read,
 350         .write  = ps3flash_user_write,
 351         .flush  = ps3flash_flush,
 352         .fsync  = ps3flash_fsync,
 353 };
 354
 355 static const struct ps3_os_area_flash_ops ps3flash_kernel_ops = {
 356         .read   = ps3flash_kernel_read,
 357         .write  = ps3flash_kernel_write,
 358 };
 359
 360 static struct miscdevice ps3flash_misc = {
 361         .minor  = MISC_DYNAMIC_MINOR,
 362         .name   = DEVICE_NAME,
 363         .fops   = &ps3flash_fops,
 364 };
 365
 366 static int __devinit ps3flash_probe(struct ps3_system_bus_device *_dev)
 367 {
 368         struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
 369         struct ps3flash_private *priv;
 370         int error;
 371         unsigned long tmp;
 372
 373         tmp = dev->regions[dev->region_idx].start*dev->blk_size;
 374         if (tmp % FLASH_BLOCK_SIZE) {
 375                 dev_err(&dev->sbd.core,
 376                         "%s:%u region start %lu is not aligned\n", __func__,
 377                         __LINE__, tmp);
 378                 return -EINVAL;
 379         }
 380         tmp = dev->regions[dev->region_idx].size*dev->blk_size;
 381         if (tmp % FLASH_BLOCK_SIZE) {
 382                 dev_err(&dev->sbd.core,
 383                         "%s:%u region size %lu is not aligned\n", __func__,
 384                         __LINE__, tmp);
 385                 return -EINVAL;
 386         }
 387
 388         /* use static buffer, kmalloc cannot allocate 256 KiB */
 389         if (!ps3flash_bounce_buffer.address)
 390                 return -ENODEV;
 391
 392         if (ps3flash_dev) {
 393                 dev_err(&dev->sbd.core,
 394                         "Only one FLASH device is supported\n");
 395                 return -EBUSY;
 396         }
 397
 398         ps3flash_dev = dev;
 399
 400         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 401         if (!priv) {
 402                 error = -ENOMEM;
 403                 goto fail;
 404         }
 405
 406         ps3_system_bus_set_drvdata(&dev->sbd, priv);
 407         mutex_init(&priv->mutex);
 408         priv->tag = -1;
 409
 410         dev->bounce_size = ps3flash_bounce_buffer.size;
 411         dev->bounce_buf = ps3flash_bounce_buffer.address;
 412         priv->chunk_sectors = dev->bounce_size / dev->blk_size;
 413
 414         error = ps3stor_setup(dev, ps3flash_interrupt);
 415         if (error)
 416                 goto fail_free_priv;
 417
 418         ps3flash_misc.parent = &dev->sbd.core;
 419         error = misc_register(&ps3flash_misc);
 420         if (error) {
 421                 dev_err(&dev->sbd.core, "%s:%u: misc_register failed %d\n",
 422                         __func__, __LINE__, error);
 423                 goto fail_teardown;
 424         }
 425
 426         dev_info(&dev->sbd.core, "%s:%u: registered misc device %d\n",
 427                  __func__, __LINE__, ps3flash_misc.minor);
 428
 429         ps3_os_area_flash_register(&ps3flash_kernel_ops);
 430         return 0;
 431
 432 fail_teardown:
 433         ps3stor_teardown(dev);
 434 fail_free_priv:
 435         kfree(priv);
 436         ps3_system_bus_set_drvdata(&dev->sbd, NULL);
 437 fail:
 438         ps3flash_dev = NULL;
 439         return error;
 440 }
 441
 442 static int ps3flash_remove(struct ps3_system_bus_device *_dev)
 443 {
 444         struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
 445
 446         ps3_os_area_flash_register(NULL);
 447         misc_deregister(&ps3flash_misc);
 448         ps3stor_teardown(dev);
 449         kfree(ps3_system_bus_get_drvdata(&dev->sbd));
 450         ps3_system_bus_set_drvdata(&dev->sbd, NULL);
 451         ps3flash_dev = NULL;
 452         return 0;
 453 }
 454
 455
 456 static struct ps3_system_bus_driver ps3flash = {
 457         .match_id       = PS3_MATCH_ID_STOR_FLASH,
 458         .core.name      = DEVICE_NAME,
 459         .core.owner     = THIS_MODULE,
 460         .probe          = ps3flash_probe,
 461         .remove         = ps3flash_remove,
 462         .shutdown       = ps3flash_remove,
 463 };
 464
 465
 466 static int __init ps3flash_init(void)
 467 {
 468         return ps3_system_bus_driver_register(&ps3flash);
 469 }
 470
 471 static void __exit ps3flash_exit(void)
 472 {
 473         ps3_system_bus_driver_unregister(&ps3flash);
 474 }
 475
 476 module_init(ps3flash_init);
 477 module_exit(ps3flash_exit);
 478
 479 MODULE_LICENSE("GPL");
 480 MODULE_DESCRIPTION("PS3 FLASH ROM Storage Driver");
 481 MODULE_AUTHOR("Sony Corporation");
 482 MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_FLASH);