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