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