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