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