yaffs_fs.c

   1 /*
   2  * YAFFS: Yet another FFS. A NAND-flash specific file system.
   3  * yaffs_fs.c
   4  *
   5  * Copyright (C) 2002 Aleph One Ltd.
   6  *   for Toby Churchill Ltd and Brightstar Engineering
   7  *
   8  * Created by Charles Manning <charles@aleph1.co.uk>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  * This is the file system front-end to YAFFS that hooks it up to
  15  * the VFS.
  16  *
  17  * Special notes:
  18  * >> sb->u.generic_sbp points to the yaffs_Device associated with this superblock
  19  * >> inode->u.generic_ip points to the associated yaffs_Object.
  20  *
  21  *
  22  * Acknowledgements:
  23  * * Luc van OostenRyck for numerous patches.
  24  * * Nick Bane for numerous patches.
  25  * * Some code bodily lifted from JFFS2.
  26  */
  27
  28
  29 #include <linux/config.h>
  30 #include <linux/kernel.h>
  31 #include <linux/module.h>
  32 #include <linux/version.h>
  33 #include <linux/slab.h>
  34 #include <linux/init.h>
  35 #include <linux/list.h>
  36 #include <linux/fs.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/mtd/mtd.h>
  40 #include <linux/interrupt.h>
  41 #include <linux/string.h>
  42 #include <linux/locks.h>
  43
  44 #include <asm/uaccess.h>
  45
  46 #include "yaffs_guts.h"
  47
  48 #ifdef CONFIG_YAFFS_RAM_ENABLED
  49 #include "yaffs_nandemul.h"
  50 // 2 MB of RAM for emulation
  51 #define YAFFS_RAM_EMULATION_SIZE  0x200000
  52 #endif //CONFIG_YAFFS_RAM_ENABLED
  53
  54 #ifdef CONFIG_YAFFS_MTD_ENABLED
  55 #include <linux/mtd/mtd.h>
  56 #include "yaffs_mtdif.h"
  57 #endif //CONFIG_YAFFS_MTD_ENABLED
  58
  59 #define T(x) printk x
  60
  61
  62
  63 #define yaffs_InodeToObject(iptr) ((yaffs_Object *)((iptr)->u.generic_ip))
  64 #define yaffs_DentryToObject(dptr) yaffs_InodeToObject((dptr)->d_inode)
  65 #define yaffs_SuperToDevice(sb) ((yaffs_Device *)sb->u.generic_sbp)
  66
  67
  68
  69 static void yaffs_put_super(struct super_block *sb);
  70
  71 static ssize_t yaffs_file_read(struct file *f, char *buf, size_t n, loff_t *pos);
  72 static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n, loff_t *pos);
  73 static int yaffs_file_flush(struct file* file);
  74
  75 static int yaffs_sync_object(struct file * file, struct dentry *dentry, int datasync);
  76
  77 static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir);
  78
  79 static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode);
  80 static struct dentry * yaffs_lookup(struct inode *dir, struct dentry *dentry);
  81 static int yaffs_link(struct dentry *old_dentry, struct inode * dir, struct dentry * dentry);
  82 static int yaffs_unlink(struct inode * dir, struct dentry *dentry);
  83 static int yaffs_symlink(struct inode * dir, struct dentry *dentry, const char * symname);
  84 static int yaffs_mkdir(struct inode * dir, struct dentry * dentry, int mode);
  85 static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode, int dev);
  86 static int yaffs_rename(struct inode * old_dir, struct dentry *old_dentry, struct inode * new_dir,struct dentry *new_dentry);
  87 static int yaffs_setattr(struct dentry *dentry, struct iattr *attr);
  88
  89 static int yaffs_statfs(struct super_block *sb, struct statfs *buf);
  90 static void yaffs_read_inode (struct inode *inode);
  91 static struct super_block *yaffs_read_super(struct super_block * sb, void * data, int silent);
  92 static void yaffs_put_inode (struct inode *inode);
  93 static void yaffs_delete_inode(struct inode *);
  94 static void yaffs_clear_inode(struct inode *);
  95
  96 static int yaffs_readpage(struct file *file, struct page * page);
  97
  98 static int yaffs_prepare_write(struct file *f, struct page *pg, unsigned offset, unsigned to);
  99 static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset, unsigned to);
 100
 101 static int yaffs_readlink(struct dentry *dentry, char *buffer, int buflen);
 102 static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
 103
 104
 105
 106
 107 static struct address_space_operations yaffs_file_address_operations = {
 108         readpage:               yaffs_readpage,
 109         prepare_write:  yaffs_prepare_write,
 110         commit_write:   yaffs_commit_write
 111 };
 112
 113
 114 static struct file_operations yaffs_file_operations = {
 115 #ifdef CONFIG_YAFFS_USE_GENERIC_RW
 116         read:           generic_file_read,
 117         write:          generic_file_write,
 118 #else
 119         read:           yaffs_file_read,
 120         write:          yaffs_file_write,
 121 #endif
 122         mmap:           generic_file_mmap,
 123         flush:          yaffs_file_flush,
 124         fsync:          yaffs_sync_object,
 125 };
 126
 127
 128 static struct inode_operations yaffs_file_inode_operations = {
 129         setattr:        yaffs_setattr,
 130 };
 131
 132
 133 struct inode_operations yaffs_symlink_inode_operations =
 134 {
 135         readlink:       yaffs_readlink,
 136         follow_link:    yaffs_follow_link,
 137         setattr:        yaffs_setattr
 138 };
 139
 140 static struct inode_operations yaffs_dir_inode_operations = {
 141         create:         yaffs_create,
 142         lookup:         yaffs_lookup,
 143         link:           yaffs_link,
 144         unlink:         yaffs_unlink,
 145         symlink:        yaffs_symlink,
 146         mkdir:          yaffs_mkdir,
 147         rmdir:          yaffs_unlink,
 148         mknod:          yaffs_mknod,
 149         rename:         yaffs_rename,
 150         setattr:        yaffs_setattr,
 151 };
 152
 153 static struct file_operations yaffs_dir_operations = {
 154         read:           generic_read_dir,
 155         readdir:        yaffs_readdir,
 156         fsync:          yaffs_sync_object,
 157 };
 158
 159
 160 static struct super_operations yaffs_super_ops = {
 161         statfs:                 yaffs_statfs,
 162         read_inode:             yaffs_read_inode,
 163         put_inode:              yaffs_put_inode,
 164         put_super:              yaffs_put_super,
 165 //      remount_fs:
 166         delete_inode:           yaffs_delete_inode,
 167         clear_inode:            yaffs_clear_inode,
 168 };
 169
 170
 171
 172 static void yaffs_GrossLock(yaffs_Device *dev)
 173 {
 174         T((KERN_DEBUG"yaffs locking\n"));
 175
 176         down(&dev->grossLock);
 177 }
 178
 179 static void yaffs_GrossUnlock(yaffs_Device *dev)
 180 {
 181         T((KERN_DEBUG"yaffs unlocking\n"));
 182         up(&dev->grossLock);
 183
 184 }
 185
 186 static int yaffs_readlink(struct dentry *dentry, char *buffer, int buflen)
 187 {
 188         unsigned char *alias;
 189         int ret;
 190
 191         yaffs_Device *dev = yaffs_DentryToObject(dentry)->myDev;
 192
 193
 194         yaffs_GrossLock(dev);
 195
 196         alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
 197
 198         yaffs_GrossUnlock(dev);
 199
 200         if(!alias)
 201                 return -ENOMEM;
 202
 203         ret = vfs_readlink(dentry, buffer, buflen, alias);
 204         kfree(alias);
 205         return ret;
 206 }
 207
 208 static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd)
 209 {
 210         unsigned char *alias;
 211         int ret;
 212         yaffs_Device *dev = yaffs_DentryToObject(dentry)->myDev;
 213
 214
 215         yaffs_GrossLock(dev);
 216
 217         alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
 218
 219         yaffs_GrossUnlock(dev);
 220
 221         if(!alias)
 222                 return -ENOMEM;
 223
 224         ret = vfs_follow_link(nd,alias);
 225         kfree(alias);
 226         return ret;
 227 }
 228
 229
 230 struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,yaffs_Object *obj);
 231
 232 /*
 233  * Lookup is used to find objects in the fs
 234  */
 235 static struct dentry * yaffs_lookup(struct inode *dir, struct dentry *dentry)
 236 {
 237         yaffs_Object *obj;
 238         struct inode *inode;
 239
 240         yaffs_Device *dev = yaffs_InodeToObject(dir)->myDev;
 241
 242
 243         yaffs_GrossLock(dev);
 244
 245
 246         T((KERN_DEBUG"yaffs_lookup for %d:%s\n",yaffs_InodeToObject(dir)->objectId,dentry->d_name.name));
 247
 248         obj = yaffs_FindObjectByName(yaffs_InodeToObject(dir),dentry->d_name.name);
 249
 250         obj = yaffs_GetEquivalentObject(obj); // in case it was a hardlink
 251
 252
 253
 254         if(obj)
 255         {
 256                 T((KERN_DEBUG"yaffs_lookup found %d\n",obj->objectId));
 257
 258                 inode = yaffs_get_inode(dir->i_sb, obj->st_mode,0,obj);
 259
 260                 if(inode)
 261                 {
 262                         T((KERN_DEBUG"yaffs_loookup dentry \n"));
 263                         //dget(dentry); // try to solve directory bug
 264                         d_add(dentry,inode);
 265
 266                         yaffs_GrossUnlock(dev);
 267
 268                         // return dentry;
 269                         return NULL;
 270                 }
 271
 272         }
 273         else
 274         {
 275                 T((KERN_DEBUG"yaffs_lookup not found\n"));
 276
 277         }
 278         yaffs_GrossUnlock(dev);
 279
 280         return NULL;
 281         //      return (ERR_PTR(-EIO));
 282
 283 }
 284
 285 // For now put inode is just for debugging
 286 // Put inode is called when the inode **structure** is put.
 287 static void yaffs_put_inode(struct inode *inode)
 288 {
 289         T(("yaffs_put_inode: ino %d, count %d\n",(int)inode->i_ino, atomic_read(&inode->i_count)));
 290
 291 }
 292
 293 // clear is called to tell the fs to release any per-inode data it holds
 294 static void yaffs_clear_inode(struct inode *inode)
 295 {
 296         yaffs_Object *obj = yaffs_InodeToObject(inode);
 297
 298         T(("yaffs_clear_inode: ino %d, count %d %s\n",(int)inode->i_ino, atomic_read(&inode->i_count),
 299                 obj ? "object exists" : "null object"));
 300
 301         if(obj)
 302         {
 303                 obj->myInode = NULL;
 304                 inode->u.generic_ip = NULL;
 305         }
 306
 307
 308 }
 309
 310 // delete is called when the link count is zero and the inode
 311 // is put (ie. nobody wants to know about it anymore, time to
 312 // delete the file).
 313 // NB Must call clear_inode()
 314 static void yaffs_delete_inode(struct inode *inode)
 315 {
 316         yaffs_Object *obj = yaffs_InodeToObject(inode);
 317         yaffs_Device *dev;
 318
 319         T(("yaffs_delete_inode: ino %d, count %d %s\n",(int)inode->i_ino, atomic_read(&inode->i_count),
 320                 obj ? "object exists" : "null object"));
 321
 322         if(obj)
 323         {
 324                 dev = obj->myDev;
 325                 yaffs_GrossLock(dev);
 326                 yaffs_DeleteFile(obj);
 327                 yaffs_GrossUnlock(dev);
 328         }
 329         clear_inode(inode);
 330 }
 331
 332
 333 static int yaffs_file_flush(struct file* file)
 334 {
 335         yaffs_Object *obj = yaffs_DentryToObject(file->f_dentry);
 336
 337         yaffs_Device *dev = obj->myDev;
 338
 339         T((KERN_DEBUG"yaffs_file_flush object %d (%s)\n",obj->objectId,
 340                                 obj->dirty ? "dirty" : "clean"));
 341
 342         yaffs_GrossLock(dev);
 343
 344     yaffs_FlushFile(obj);
 345
 346         yaffs_GrossUnlock(dev);
 347
 348     return 0;
 349 }
 350
 351
 352
 353 static int yaffs_readpage_nolock(struct file *f, struct page * pg)
 354 {
 355         // Lifted from jffs2
 356
 357         yaffs_Object *obj;
 358         unsigned char *pg_buf;
 359         int ret;
 360
 361         yaffs_Device *dev;
 362
 363         T((KERN_DEBUG"yaffs_readpage at %08x, size %08x\n",
 364                       pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE));
 365
 366         obj  = yaffs_DentryToObject(f->f_dentry);
 367
 368         dev = obj->myDev;
 369
 370
 371         if (!PageLocked(pg))
 372                 PAGE_BUG(pg);
 373
 374         pg_buf = kmap(pg);
 375         /* FIXME: Can kmap fail? */
 376
 377         yaffs_GrossLock(dev);
 378
 379         ret = yaffs_ReadDataFromFile(obj, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);
 380
 381         yaffs_GrossUnlock(dev);
 382
 383         if(ret >= 0) ret = 0;
 384
 385         if (ret) {
 386                 ClearPageUptodate(pg);
 387                 SetPageError(pg);
 388         } else {
 389                 SetPageUptodate(pg);
 390                 ClearPageError(pg);
 391         }
 392
 393         flush_dcache_page(pg);
 394         kunmap(pg);
 395
 396
 397         T((KERN_DEBUG"yaffs_readpage done\n"));
 398         return ret;
 399 }
 400
 401 static int yaffs_readpage_unlock(struct file *f, struct page *pg)
 402 {
 403         int ret = yaffs_readpage_nolock(f,pg);
 404         UnlockPage(pg);
 405         return ret;
 406 }
 407
 408 static int yaffs_readpage(struct file *f, struct page * pg)
 409 {
 410         return yaffs_readpage_unlock(f,pg);
 411 }
 412
 413
 414 static int yaffs_prepare_write(struct file *f, struct page *pg, unsigned offset, unsigned to)
 415 {
 416
 417         T((KERN_DEBUG"yaffs_prepair_write\n"));
 418         if(!Page_Uptodate(pg) && (offset || to < PAGE_CACHE_SIZE))
 419                 return  yaffs_readpage_nolock(f,pg);
 420
 421         return 0;
 422
 423 }
 424
 425 static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset, unsigned to)
 426 {
 427
 428         void *addr = page_address(pg) + offset;
 429         loff_t pos = (((loff_t)pg->index) << PAGE_CACHE_SHIFT) + offset;
 430         int nBytes = to - offset;
 431         int nWritten;
 432
 433         unsigned spos = pos;
 434         unsigned saddr = addr;
 435
 436         T((KERN_DEBUG"yaffs_commit_write addr %x pos %x nBytes %d\n",saddr,spos,nBytes));
 437
 438         nWritten = yaffs_file_write(f,addr, nBytes, &pos);
 439
 440         if(nWritten != nBytes)
 441         {
 442                 T((KERN_DEBUG"yaffs_commit_write not same size nWritten %d  nBytes %d\n",nWritten,nBytes));
 443                 SetPageError(pg);
 444                 ClearPageUptodate(pg);
 445         }
 446         else
 447         {
 448                 SetPageUptodate(pg);
 449         }
 450
 451         T((KERN_DEBUG"yaffs_commit_write returning %d\n",nWritten));
 452
 453         return nWritten;
 454
 455 }
 456
 457
 458
 459 static void yaffs_FillInodeFromObject(struct inode *inode, yaffs_Object *obj)
 460 {
 461         if (inode && obj)
 462         {
 463                 inode->i_ino = obj->objectId;
 464                 inode->i_mode = obj->st_mode;
 465                 inode->i_uid = obj->st_uid;
 466                 inode->i_gid = obj->st_gid;
 467                 inode->i_blksize = inode->i_sb->s_blocksize;
 468                 inode->i_blocks = 0;
 469                 inode->i_rdev = obj->st_rdev;;
 470                 inode->i_atime = obj->st_atime;
 471                 inode->i_mtime = obj->st_mtime;
 472                 inode->i_ctime = obj->st_ctime;
 473                 inode->i_size = yaffs_GetObjectFileLength(obj);
 474                 inode->i_nlink = yaffs_GetObjectLinkCount(obj);
 475
 476                 T((KERN_DEBUG"yaffs_FillInode mode %x uid %d gid %d size %d count %d\n",
 477                                 inode->i_mode, inode->i_uid, inode->i_gid, (int)inode->i_size, atomic_read(&inode->i_count)));
 478
 479                 switch (obj->st_mode & S_IFMT)
 480                 {
 481                         default: // fifo, device or socket
 482                                 init_special_inode(inode, obj->st_mode, obj->st_rdev);
 483                                 break;
 484                         case S_IFREG:   // file
 485                                 inode->i_op = &yaffs_file_inode_operations;
 486                                 inode->i_fop = &yaffs_file_operations;
 487                                 inode->i_mapping->a_ops = &yaffs_file_address_operations;
 488                                 break;
 489                         case S_IFDIR:   // directory
 490                                 inode->i_op = &yaffs_dir_inode_operations;
 491                                 inode->i_fop = &yaffs_dir_operations;
 492                                 break;
 493                         case S_IFLNK:   // symlink
 494                                 inode->i_op = &yaffs_symlink_inode_operations;
 495                                 break;
 496                 }
 497
 498
 499                 inode->u.generic_ip = obj;
 500                 obj->myInode = inode;
 501
 502         }
 503         else
 504         {
 505                 T((KERN_DEBUG"yaffs_FileInode invalid parameters\n"));
 506         }
 507
 508 }
 509
 510 struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,yaffs_Object *obj)
 511 {
 512         struct inode * inode;
 513
 514         T((KERN_DEBUG"yaffs_get_inode for object %d\n",obj->objectId));
 515
 516         inode = iget(sb,obj->objectId);
 517
 518         // NB Side effect: iget calls back to yaffs_read_inode().
 519         // iget also increments the inode's i_count
 520
 521         return inode;
 522 }
 523
 524 static ssize_t yaffs_file_read(struct file *f, char *buf, size_t n, loff_t *pos)
 525 {
 526         yaffs_Object *obj;
 527         int nRead,ipos;
 528         struct inode *inode;
 529         yaffs_Device *dev;
 530
 531         T((KERN_DEBUG"yaffs_file_read\n"));
 532
 533         obj  = yaffs_DentryToObject(f->f_dentry);
 534
 535         dev = obj->myDev;
 536
 537         yaffs_GrossLock(dev);
 538
 539         inode = f->f_dentry->d_inode;
 540
 541         if (*pos < inode->i_size)
 542         {
 543                         if (*pos + n > inode->i_size)
 544                         {
 545                                 n = inode->i_size - *pos;
 546                         }
 547         }
 548         else
 549         {
 550                 n = 0;
 551         }
 552
 553         nRead = yaffs_ReadDataFromFile(obj,buf,*pos,n);
 554         if(nRead > 0)
 555         {
 556                 f->f_pos += nRead;
 557         }
 558
 559         yaffs_GrossUnlock(dev);
 560
 561         ipos = *pos;
 562
 563         T((KERN_DEBUG"yaffs_file_read read %d bytes, %d read at %d\n",n,nRead,ipos));
 564         return nRead;
 565
 566 }
 567
 568
 569 static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n, loff_t *pos)
 570 {
 571         yaffs_Object *obj;
 572         int nWritten,ipos;
 573         struct inode *inode;
 574         yaffs_Device *dev;
 575
 576
 577         obj  = yaffs_DentryToObject(f->f_dentry);
 578
 579         dev = obj->myDev;
 580
 581         yaffs_GrossLock(dev);
 582
 583         inode = f->f_dentry->d_inode;
 584
 585         if(!S_ISBLK(inode->i_mode) && f->f_flags & O_APPEND)
 586         {
 587                 ipos = inode->i_size;
 588         }
 589         else
 590         {
 591                 ipos = *pos;
 592         }
 593
 594
 595         if(!obj)
 596         {
 597                 T((KERN_DEBUG"yaffs_file_write: hey obj is null!\n"));
 598         }
 599         else
 600         {
 601                 T((KERN_DEBUG"yaffs_file_write about to write writing %d bytes to object %d at %d\n",n,obj->objectId,ipos));
 602         }
 603
 604         nWritten = yaffs_WriteDataToFile(obj,buf,ipos,n);
 605
 606         T((KERN_DEBUG"yaffs_file_write writing %d bytes, %d written at %d\n",n,nWritten,ipos));
 607         if(nWritten > 0)
 608         {
 609                 ipos += nWritten;
 610                 *pos = ipos;
 611                 if(ipos > inode->i_size)
 612                 {
 613                         inode->i_size = ipos;
 614                         inode->i_blocks = (ipos + inode->i_blksize - 1)/ inode->i_blksize;
 615
 616                         T((KERN_DEBUG"yaffs_file_write size updated to %d bytes, %d blocks\n",ipos,inode->i_blocks));
 617                 }
 618
 619         }
 620         yaffs_GrossUnlock(dev);
 621
 622         return nWritten != n ? -ENOSPC : nWritten;
 623 }
 624
 625
 626 static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir)
 627 {
 628         yaffs_Object *obj;
 629         yaffs_Device *dev;
 630         struct inode *inode = f->f_dentry->d_inode;
 631         unsigned long offset, curoffs;
 632         struct list_head *i;
 633         yaffs_Object *l;
 634
 635         char name[YAFFS_MAX_NAME_LENGTH +1];
 636
 637         obj =  yaffs_DentryToObject(f->f_dentry);
 638         dev = obj->myDev;
 639
 640         yaffs_GrossLock(dev);
 641
 642         offset = f->f_pos;
 643
 644         T(("yaffs_readdir: starting at %d\n",(int)offset));
 645
 646         if(offset == 0)
 647         {
 648         T((KERN_DEBUG"yaffs_readdir: entry . ino %d \n",(int)inode->i_ino));
 649                 if(filldir(dirent,".",1,offset,inode->i_ino,DT_DIR) < 0)
 650                 {
 651                         goto out;
 652                 }
 653                 offset++;
 654                 f->f_pos++;
 655         }
 656         if(offset == 1)
 657         {
 658                 T((KERN_DEBUG"yaffs_readdir: entry .. ino %d \n",(int)f->f_dentry->d_parent->d_inode->i_ino));
 659                 if(filldir(dirent,"..",2,offset,f->f_dentry->d_parent->d_inode->i_ino,DT_DIR) < 0)
 660                 {
 661                         goto out;
 662                 }
 663                 offset++;
 664                 f->f_pos++;
 665         }
 666
 667         curoffs = 1;
 668
 669         list_for_each(i,&obj->variant.directoryVariant.children)
 670         {
 671                 curoffs++;
 672                 if(curoffs >= offset)
 673                 {
 674                         l = list_entry(i, yaffs_Object,siblings);
 675
 676                         yaffs_GetObjectName(l,name,YAFFS_MAX_NAME_LENGTH+1);
 677                         T((KERN_DEBUG"yaffs_readdir: %s inode %d\n",name,yaffs_GetObjectInode(l)));
 678
 679                         if(filldir(dirent,
 680                                            name,
 681                                            strlen(name),
 682                                            offset,
 683                                            yaffs_GetObjectInode(l),
 684                                            yaffs_GetObjectType(l))
 685                                            < 0)
 686                         {
 687                                 goto up_and_out;
 688                         }
 689
 690                         offset++;
 691                         f->f_pos++;
 692                 }
 693         }
 694
 695   up_and_out:
 696   out:
 697
 698     yaffs_GrossUnlock(dev);
 699
 700         return 0;
 701 }
 702
 703
 704 /*
 705  * File creation. Allocate an inode, and we're done..
 706  */
 707 static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode, int dev)
 708 {
 709         struct inode *inode;
 710
 711         yaffs_Object *obj = NULL;
 712         yaffs_Device *dev;
 713
 714         yaffs_Object *parent = yaffs_InodeToObject(dir);
 715
 716         int error = -ENOSPC;
 717
 718         if(parent)
 719         {
 720                 T((KERN_DEBUG"yaffs_mknod: parent object %d type %d\n",
 721                                          parent->objectId,parent->variantType));
 722         }
 723         else
 724         {
 725                 T((KERN_DEBUG"yaffs_mknod: could not get parent object\n"));
 726                 return -EPERM;
 727         }
 728
 729         T(("yaffs_mknod: making oject for %s, mode %x dev %x\n",
 730                                         dentry->d_name.name, mode,dev));
 731
 732         dev = parent->myDev;
 733
 734         yaffs_GrossLock(dev);
 735
 736         switch (mode & S_IFMT)
 737         {
 738                 default:
 739                         // Special (socket, fifo, device...)
 740                         T((KERN_DEBUG"yaffs_mknod: making special\n"));
 741                         obj = yaffs_MknodSpecial(parent,dentry->d_name.name,mode,current->uid, current->gid,dev);
 742                         break;
 743                 case S_IFREG:   // file
 744                         T((KERN_DEBUG"yaffs_mknod: making file\n"));
 745                         obj = yaffs_MknodFile(parent,dentry->d_name.name,mode,current->uid, current->gid);
 746                         break;
 747                 case S_IFDIR:   // directory
 748                         T((KERN_DEBUG"yaffs_mknod: making directory\n"));
 749                         obj = yaffs_MknodDirectory(parent,dentry->d_name.name,mode,current->uid, current->gid);
 750                         break;
 751                 case S_IFLNK:   // symlink
 752                         T((KERN_DEBUG"yaffs_mknod: making file\n"));
 753                         obj = NULL; // Do we ever get here?
 754                         break;
 755         }
 756
 757         if(obj)
 758         {
 759                 inode = yaffs_get_inode(dir->i_sb, mode, dev, obj);
 760                 d_instantiate(dentry, inode);
 761                 T((KERN_DEBUG"yaffs_mknod created object %d count = %d\n",obj->objectId,atomic_read(&inode->i_count)));
 762                 error = 0;
 763         }
 764         else
 765         {
 766                 T((KERN_DEBUG"yaffs_mknod failed making object\n"));
 767                 error = -ENOMEM;
 768         }
 769
 770         yaffs_GrossUnlock(dev);
 771
 772         return error;
 773 }
 774
 775 static int yaffs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
 776 {
 777         int retVal;
 778         T((KERN_DEBUG"yaffs_mkdir\n"));
 779         retVal =  yaffs_mknod(dir, dentry, mode | S_IFDIR, 0);
 780 #if 0
 781  // attempt to fix dir bug - didn't work
 782         if(!retVal)
 783         {
 784                 dget(dentry);
 785         }
 786 #endif
 787         return retVal;
 788 }
 789
 790 static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode)
 791 {
 792         T((KERN_DEBUG"yaffs_create\n"));
 793         return yaffs_mknod(dir, dentry, mode | S_IFREG, 0);
 794 }
 795
 796
 797 static int yaffs_unlink(struct inode * dir, struct dentry *dentry)
 798 {
 799         int retVal;
 800         int nlinks;
 801
 802         yaffs_Device *dev;
 803
 804
 805         T((KERN_DEBUG"yaffs_unlink %d:%s\n",dir->i_ino,dentry->d_name.name));
 806
 807         dev = yaffs_InodeToObject(dir)->myDev;
 808
 809         yaffs_GrossLock(dev);
 810
 811         nlinks =
 812
 813         retVal = yaffs_Unlink(yaffs_InodeToObject(dir),dentry->d_name.name);
 814
 815
 816         yaffs_GrossUnlock(dev);
 817
 818         if( retVal == YAFFS_OK)
 819         {
 820                 dentry->d_inode->i_nlink--;
 821                 return 0;
 822         }
 823         else
 824         {
 825                 return -ENOTEMPTY;
 826         }
 827 }
 828
 829
 830 /*
 831  * Create a link...
 832  */
 833 static int yaffs_link(struct dentry *old_dentry, struct inode * dir, struct dentry * dentry)
 834 {
 835         struct inode *inode = old_dentry->d_inode;
 836         yaffs_Object *obj = NULL;
 837         yaffs_Object *link=NULL;
 838         yaffs_Device *dev;
 839
 840         T((KERN_DEBUG"yaffs_link\n"));
 841
 842         obj = yaffs_InodeToObject(inode);
 843         dev = obj->myDev;
 844
 845         yaffs_GrossLock(dev);
 846
 847         link = yaffs_Link(yaffs_InodeToObject(dir),dentry->d_name.name,obj);
 848
 849
 850         if(link)
 851         {
 852                 old_dentry->d_inode->i_nlink =  yaffs_GetObjectLinkCount(obj);
 853                 d_instantiate(dentry, old_dentry->d_inode);
 854                 atomic_inc(&old_dentry->d_inode->i_count);
 855                 T((KERN_DEBUG"yaffs_link link count %d i_count %d\n",
 856                         old_dentry->d_inode->i_nlink,atomic_read(&old_dentry->d_inode->i_count)));
 857
 858         }
 859
 860         yaffs_GrossUnlock(dev);
 861
 862
 863         if(link)
 864         {
 865
 866                 return 0;
 867         }
 868
 869
 870         return -EPERM;
 871 }
 872
 873
 874 static int yaffs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
 875 {
 876         yaffs_Object *obj;
 877         yaffs_Device *dev;
 878
 879         T((KERN_DEBUG"yaffs_symlink\n"));
 880
 881         dev = yaffs_InodeToObject(dir)->myDev;
 882         yaffs_GrossLock(dev);
 883         obj = yaffs_MknodSymLink(yaffs_InodeToObject(dir), dentry->d_name.name,
 884                                                          S_IFLNK | S_IRWXUGO, current->uid, current->gid,
 885                                                          symname);
 886         yaffs_GrossUnlock(dev);
 887
 888         if(obj)
 889         {
 890                 T((KERN_DEBUG"symlink created OK\n"));
 891                 return 0;
 892         }
 893         else
 894         {
 895                 T((KERN_DEBUG"symlink not created\n"));
 896
 897         }
 898
 899         return -ENOMEM;
 900 }
 901
 902 static int yaffs_sync_object(struct file * file, struct dentry *dentry, int datasync)
 903 {
 904
 905         yaffs_Object *obj;
 906         yaffs_Device *dev;
 907
 908         obj = yaffs_DentryToObject(dentry);
 909
 910         dev = obj->myDev;
 911
 912         T((KERN_DEBUG"yaffs_sync_object\n"));
 913         yaffs_GrossLock(dev);
 914         yaffs_FlushFile(obj);
 915         yaffs_GrossUnlock(dev);
 916         return 0;
 917 }
 918
 919 /*
 920  * The VFS layer already does all the dentry stuff for rename.
 921  *
 922  * NB: POSIX says you can rename an object over an old object of the same name
 923  */
 924 static int yaffs_rename(struct inode * old_dir, struct dentry *old_dentry, struct inode * new_dir,struct dentry *new_dentry)
 925 {
 926         yaffs_Device *dev;
 927         int retVal;
 928
 929         dev = yaffs_InodeToObject(old_dir)->myDev;
 930
 931         yaffs_GrossLock(dev);
 932
 933         retVal =  yaffs_RenameObject(yaffs_InodeToObject(old_dir),old_dentry->d_name.name,
 934                                          yaffs_InodeToObject(new_dir),new_dentry->d_name.name);
 935         yaffs_GrossUnlock(dev);
 936
 937         if(retVal == YAFFS_OK)
 938         {
 939                 return 0;
 940         }
 941         else
 942         {
 943                 return -ENOTEMPTY;
 944         }
 945
 946
 947 }
 948
 949 static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
 950 {
 951         struct inode *inode = dentry->d_inode;
 952         int error;
 953         yaffs_Device *dev;
 954
 955         T((KERN_DEBUG"yaffs_setattr of object %d\n",yaffs_InodeToObject(inode)->objectId));
 956
 957         if((error = inode_change_ok(inode,attr)) == 0)
 958         {
 959
 960                 dev = yaffs_InodeToObject(inode)->myDev;
 961                 yaffs_GrossLock(dev);
 962                 if(yaffs_SetAttributes(yaffs_InodeToObject(inode),attr) == YAFFS_OK)
 963                 {
 964                         error = 0;
 965                 }
 966                 else
 967                 {
 968                         error = -EPERM;
 969                 }
 970                 yaffs_GrossUnlock(dev);
 971                 inode_setattr(inode,attr);
 972         }
 973         return error;
 974 }
 975
 976 static int yaffs_statfs(struct super_block *sb, struct statfs *buf)
 977 {
 978         yaffs_Device *dev = yaffs_SuperToDevice(sb);
 979         T((KERN_DEBUG"yaffs_statfs\n"));
 980
 981         yaffs_GrossLock(dev);
 982
 983         buf->f_type = YAFFS_MAGIC;
 984         buf->f_bsize = sb->s_blocksize;
 985         buf->f_namelen = 255;
 986         buf->f_blocks = (dev->endBlock - dev->startBlock + 1) * YAFFS_CHUNKS_PER_BLOCK/
 987                                                 (sb->s_blocksize/YAFFS_BYTES_PER_CHUNK);
 988         buf->f_files = 0;
 989         buf->f_ffree = 0;
 990         buf->f_bfree = yaffs_GetNumberOfFreeChunks(dev)/
 991                                                 (sb->s_blocksize/YAFFS_BYTES_PER_CHUNK);
 992         buf->f_bavail =  buf->f_bfree;
 993
 994         yaffs_GrossUnlock(dev);
 995         return 0;
 996 }
 997
 998 static void yaffs_read_inode (struct inode *inode)
 999 {
1000         // NB This is called as a side effect of other functions and
1001         // thus gross locking should always be in place already.
1002
1003         yaffs_Object *obj ;
1004         yaffs_Device *dev = yaffs_SuperToDevice(inode->i_sb);
1005
1006         T((KERN_DEBUG"yaffs_read_inode for %d\n",(int)inode->i_ino));
1007
1008         obj  = yaffs_FindObjectByNumber(dev,inode->i_ino);
1009
1010         yaffs_FillInodeFromObject(inode,obj);
1011
1012 }
1013
1014
1015 static void yaffs_put_super(struct super_block *sb)
1016 {
1017         yaffs_Device *dev = yaffs_SuperToDevice(sb);
1018
1019         yaffs_GrossLock(dev);
1020         if(dev->putSuperFunc)
1021         {
1022                  dev->putSuperFunc(sb);
1023         }
1024         yaffs_Deinitialise(dev);
1025         yaffs_GrossUnlock(dev);
1026
1027         kfree(dev);
1028 }
1029
1030
1031 #ifdef CONFIG_YAFFS_MTD_ENABLED
1032
1033 static void  yaffs_MTDPutSuper(struct super_block *sb)
1034 {
1035
1036         struct mtd_info *mtd = yaffs_SuperToDevice(sb)->genericDevice;
1037
1038         if(mtd->sync)
1039         {
1040                 mtd->sync(mtd);
1041         }
1042
1043         put_mtd_device(mtd);
1044 }
1045
1046 #endif
1047
1048 static struct super_block *yaffs_internal_read_super(int useRam, struct super_block * sb, void * data, int silent)
1049 {
1050         int nBlocks;
1051         struct inode * inode;
1052         struct dentry * root;
1053         yaffs_Device *dev;
1054
1055         sb->s_magic = YAFFS_MAGIC;
1056         sb->s_op = &yaffs_super_ops;
1057
1058         if(!sb)
1059                 printk(KERN_INFO"yaffs: sb is NULL\n");
1060         else if(!sb->s_dev)
1061                 printk(KERN_INFO"yaffs: sb->s_dev is NULL\n");
1062         else if(! kdevname(sb->s_dev))
1063                 printk(KERN_INFO"yaffs: kdevname is NULL\n");
1064         else
1065                 printk(KERN_INFO"yaffs: dev is %d name is \"%s\"\n", sb->s_dev, kdevname(sb->s_dev));
1066
1067
1068
1069 #ifdef CONFIG_YAFFS_USE_CHUNK_SIZE
1070         sb->s_blocksize = YAFFS_BYTES_PER_CHUNK;
1071         sb->s_blocksize_bits = YAFFS_CHUNK_SIZE_SHIFT;
1072 #else
1073         sb->s_blocksize = PAGE_CACHE_SIZE;
1074         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1075 #endif
1076         T(("yaffs_read_super: %s block size %d\n", useRam ? "RAM" : "MTD",sb->s_blocksize));
1077
1078 #ifdef CONFIG_YAFFS_DISABLE_WRITE_VERIFY
1079         T(("yaffs: Write verification disabled. All guarantees null and void\n");
1080 #endif
1081
1082
1083
1084         if(useRam)
1085         {
1086
1087 #ifdef CONFIG_YAFFS_RAM_ENABLED
1088                 // Set the yaffs_Device up for ram emulation
1089
1090                 sb->u.generic_sbp =     dev = kmalloc(sizeof(yaffs_Device),GFP_KERNEL);
1091                 if(!dev)
1092                 {
1093                         // Deep shit could not allocate device structure
1094                         printk(KERN_DEBUG"yaffs_read_super: Failed trying to allocate yaffs_Device. Terminating debug.\n");
1095                         return NULL;
1096                 }
1097
1098                 memset(dev,0,sizeof(yaffs_Device));
1099                 dev->genericDevice = NULL; // Not used for RAM emulation.
1100
1101                 nBlocks = YAFFS_RAM_EMULATION_SIZE / (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK);
1102                 dev->startBlock = 1;  // Don't use block 0
1103                 dev->endBlock = nBlocks - 1;
1104
1105                 dev->writeChunkToNAND = nandemul_WriteChunkToNAND;
1106                 dev->readChunkFromNAND = nandemul_ReadChunkFromNAND;
1107                 dev->eraseBlockInNAND = nandemul_EraseBlockInNAND;
1108                 dev->initialiseNAND = nandemul_InitialiseNAND;
1109
1110 #endif
1111
1112         }
1113         else
1114         {
1115 #ifdef CONFIG_YAFFS_MTD_ENABLED
1116                 struct mtd_info *mtd;
1117
1118                 printk(KERN_DEBUG "yaffs: Attempting MTD mount on %u.%u, \"%s\"\n",
1119                  MAJOR(sb->s_dev),MINOR(sb->s_dev),kdevname(sb->s_dev));
1120
1121                 // Hope it's a NAND mtd
1122                 mtd = get_mtd_device(NULL, MINOR(sb->s_dev));
1123                 if (!mtd)
1124                 {
1125                         printk(KERN_DEBUG "yaffs: MTD device #%u doesn't appear to exist\n", MINOR(sb->s_dev));
1126                         return NULL;
1127                 }
1128
1129                 if(mtd->type != MTD_NANDFLASH)
1130                 {
1131                         printk(KERN_DEBUG "yaffs: MTD device is not NAND it's type %d\n", mtd->type);
1132                         return NULL;
1133                 }
1134
1135                 printk(KERN_DEBUG" erase %x\n",mtd->erase);
1136                 printk(KERN_DEBUG" read %x\n",mtd->read);
1137                 printk(KERN_DEBUG" write %x\n",mtd->write);
1138                 printk(KERN_DEBUG" readoob %x\n",mtd->read_oob);
1139                 printk(KERN_DEBUG" writeoob %x\n",mtd->write_oob);
1140                 printk(KERN_DEBUG" oobblock %x\n",mtd->oobblock);
1141                 printk(KERN_DEBUG" oobsize %x\n",mtd->oobsize);
1142
1143
1144                 if(!mtd->erase ||
1145                    !mtd->read  ||
1146                    !mtd->write ||
1147                    !mtd->read_oob ||
1148                    !mtd->write_oob)
1149                 {
1150                         printk(KERN_DEBUG "yaffs: MTD device does not support required functions\n");
1151                         return NULL;
1152                 }
1153
1154                 if(mtd->oobblock != YAFFS_BYTES_PER_CHUNK ||
1155                    mtd->oobsize != YAFFS_BYTES_PER_SPARE)
1156                 {
1157                         printk(KERN_DEBUG "yaffs: MTD device does not support have the right page sizes\n");
1158                         return NULL;
1159                 }
1160
1161
1162                 // OK, so if we got here, we have an MTD that's NAND and looks
1163                 // like it has the right capabilities
1164                 // Set the yaffs_Device up for ram emulation
1165
1166                 sb->u.generic_sbp =     dev = kmalloc(sizeof(yaffs_Device),GFP_KERNEL);
1167                 if(!dev)
1168                 {
1169                         // Deep shit could not allocate device structure
1170                         printk(KERN_DEBUG"yaffs_read_super: Failed trying to allocate yaffs_Device. Terminating debug.\n");
1171                         return NULL;
1172                 }
1173
1174                 memset(dev,0,sizeof(yaffs_Device));
1175                 dev->genericDevice = mtd;
1176
1177                 // Set up the memory size parameters....
1178
1179                 nBlocks = mtd->size / (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK);
1180                 dev->startBlock = 1;  // Don't use block 0
1181                 dev->endBlock = nBlocks - 1;
1182
1183                 // ... and the functions.
1184                 dev->writeChunkToNAND = nandmtd_WriteChunkToNAND;
1185                 dev->readChunkFromNAND = nandmtd_ReadChunkFromNAND;
1186                 dev->eraseBlockInNAND = nandmtd_EraseBlockInNAND;
1187                 dev->initialiseNAND = nandmtd_InitialiseNAND;
1188
1189                 dev->putSuperFunc = yaffs_MTDPutSuper;
1190 #endif
1191         }
1192
1193         init_MUTEX(&dev->grossLock);
1194
1195
1196         yaffs_GrossLock(dev);
1197         yaffs_GutsInitialise(yaffs_SuperToDevice(sb));
1198
1199         T(("yaffs_read_super: guts initialised\n"));
1200
1201         // Create root inode
1202         inode = yaffs_get_inode(sb, S_IFDIR | 0755, 0,yaffs_Root(yaffs_SuperToDevice(sb)));
1203
1204         yaffs_GrossUnlock(dev);
1205
1206         if (!inode)
1207                 return NULL;
1208
1209         T(("yaffs_read_super: got root inode\n"));
1210
1211
1212         root = d_alloc_root(inode);
1213
1214         T(("yaffs_read_super: d_alloc_root done\n"));
1215
1216         if (!root) {
1217                 iput(inode);
1218                 return NULL;
1219         }
1220         sb->s_root = root;
1221
1222         T(("yaffs_read_super: done\n"));
1223         return sb;
1224 }
1225
1226 #ifdef CONFIG_YAFFS_MTD_ENABLED
1227 static struct super_block *yaffs_read_super(struct super_block * sb, void * data, int silent)
1228 {
1229         return yaffs_internal_read_super(0,sb,data,silent);
1230 }
1231
1232 static DECLARE_FSTYPE(yaffs_fs_type, "yaffs", yaffs_read_super, FS_REQUIRES_DEV);
1233 #endif
1234
1235 #ifdef CONFIG_YAFFS_RAM_ENABLED
1236
1237 static struct super_block *yaffs_ram_read_super(struct super_block * sb, void * data, int silent)
1238 {
1239         return yaffs_internal_read_super(1,sb,data,silent);
1240 }
1241
1242 static DECLARE_FSTYPE(yaffs_ram_fs_type, "yaffsram", yaffs_ram_read_super, FS_SINGLE);
1243 #endif // CONFIG_YAFFS_RAM_ENABLED
1244
1245
1246 static struct proc_dir_entry *my_proc_entry;
1247 static struct proc_dir_entry *my_proc_ram_write_entry;
1248
1249
1250 static int  yaffs_proc_read(
1251         char *page,
1252         char **start,
1253         off_t offset,
1254         int count,
1255         int *eof,
1256         void *data
1257         )
1258 {
1259
1260         static char my_buffer[1000];
1261
1262         if (offset > 0) return 0;
1263
1264         /* Fill the buffer and get its length */
1265         sprintf( my_buffer,
1266                 "YAFFS built:"__DATE__ " "__TIME__"\n"
1267
1268         );
1269
1270         strcpy(page,my_buffer);
1271         return strlen(my_buffer);
1272 }
1273
1274
1275 static int  yaffs_proc_ram_write(
1276         char *page,
1277         char **start,
1278         off_t offset,
1279         int count,
1280         int *eof,
1281         void *data
1282         )
1283 {
1284
1285         printk(KERN_DEBUG "yaffs write size %d\n",count);
1286         return count;
1287 }
1288
1289 static int __init init_yaffs_fs(void)
1290 {
1291         int error = 0;
1292
1293         printk(KERN_DEBUG "yaffs " __DATE__ " " __TIME__ " Initialisation\n");
1294 #ifdef CONFIG_YAFFS_USE_GENERIC_RW
1295         printk(KERN_DEBUG "yaffs is using generic read/write (caching)\n");
1296 #else
1297         printk(KERN_DEBUG "yaffs is using direct read/write (uncached)\n");
1298 #endif
1299
1300
1301     /* Install the proc_fs entry */
1302     my_proc_entry = create_proc_read_entry("yaffs",
1303                                            S_IRUGO | S_IFREG,
1304                                            &proc_root,
1305                                            yaffs_proc_read,
1306                                            NULL);
1307     if(!my_proc_entry)
1308     {
1309        return -ENOMEM;
1310     }
1311
1312 #ifdef CONFIG_YAFFS_RAM_ENABLED
1313
1314     my_proc_ram_write_entry = create_proc_entry("yaffs_ram",
1315                                            S_IRUGO | S_IFREG,
1316                                            &proc_root);
1317
1318     if(!my_proc_ram_write_entry)
1319     {
1320        return -ENOMEM;
1321     }
1322     else
1323     {
1324         my_proc_ram_write_entry->write_proc = yaffs_proc_ram_write;
1325     }
1326     error = register_filesystem(&yaffs_ram_fs_type);
1327     if(error)
1328     {
1329         return error;
1330     }
1331 #endif //CONFIG_YAFFS_RAM_ENABLED
1332
1333 #ifdef CONFIG_YAFFS_MTD_ENABLED
1334         error = register_filesystem(&yaffs_fs_type);
1335         if(error)
1336         {
1337 #ifdef CONFIG_YAFFS_RAM_ENABLED
1338                 unregister_filesystem(&yaffs_ram_fs_type);
1339 #endif //CONFIG_YAFFS_RAM_ENABLED
1340         }
1341 #endif // CONFIG_YAFFS_MTD_ENABLED
1342
1343         return error;
1344 }
1345
1346 static void __exit exit_yaffs_fs(void)
1347 {
1348         printk(KERN_DEBUG "yaffs " __DATE__ " " __TIME__ " Clean up\n");
1349
1350     remove_proc_entry("yaffs",&proc_root);
1351
1352 #ifdef CONFIG_YAFFS_RAM_ENABLED
1353         unregister_filesystem(&yaffs_ram_fs_type);
1354 #endif
1355 #ifdef CONFIG_YAFFS_MTD_ENABLED
1356         unregister_filesystem(&yaffs_fs_type);
1357 #endif
1358
1359 }
1360
1361 module_init(init_yaffs_fs)
1362 module_exit(exit_yaffs_fs)
1363
1364 MODULE_DESCRIPTION("YAFFS - a NAND specific flash file system");
1365 MODULE_AUTHOR("Charles Manning, Aleph One Ltd., 2002");
1366 MODULE_LICENSE("GPL");
1367