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 patches marked NCB.
  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 int yaffs_readpage(struct file *file, struct page * page);
  94
  95 static int yaffs_prepare_write(struct file *f, struct page *pg, unsigned offset, unsigned to);
  96 static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset, unsigned to);
  97
  98 static int yaffs_readlink(struct dentry *dentry, char *buffer, int buflen);
  99 static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
 100
 101
 102
 103
 104
 105 static struct address_space_operations yaffs_file_address_operations = {
 106         readpage:               yaffs_readpage,
 107         prepare_write:  yaffs_prepare_write,
 108         commit_write:   yaffs_commit_write
 109 };
 110
 111
 112 static struct file_operations yaffs_file_operations = {
 113 #ifdef CONFIG_YAFFS_USE_GENERIC_RW
 114         read:           generic_file_read,
 115         write:          generic_file_write,
 116 #else
 117         read:           yaffs_file_read,
 118         write:          yaffs_file_write,
 119 #endif
 120         mmap:           generic_file_mmap,
 121         flush:          yaffs_file_flush,
 122         fsync:          yaffs_sync_object,
 123 };
 124
 125
 126 static struct inode_operations yaffs_file_inode_operations = {
 127         setattr:        yaffs_setattr,
 128 };
 129
 130
 131 struct inode_operations yaffs_symlink_inode_operations =
 132 {
 133         readlink:       yaffs_readlink,
 134         follow_link:    yaffs_follow_link,
 135         setattr:        yaffs_setattr
 136 };
 137
 138 static struct inode_operations yaffs_dir_inode_operations = {
 139         create:         yaffs_create,
 140         lookup:         yaffs_lookup,
 141         link:           yaffs_link,
 142         unlink:         yaffs_unlink,
 143         symlink:        yaffs_symlink,
 144         mkdir:          yaffs_mkdir,
 145         rmdir:          yaffs_unlink,
 146         mknod:          yaffs_mknod,
 147         rename:         yaffs_rename,
 148         setattr:        yaffs_setattr,
 149 };
 150
 151 static struct file_operations yaffs_dir_operations = {
 152         read:           generic_read_dir,
 153         readdir:        yaffs_readdir,
 154         fsync:          yaffs_sync_object,
 155 };
 156
 157
 158 static struct super_operations yaffs_super_ops = {
 159         statfs:                 yaffs_statfs,
 160         read_inode:             yaffs_read_inode,
 161         put_inode:              yaffs_put_inode,
 162         put_super:              yaffs_put_super,
 163 //      read_inode:
 164 //      remount_fs:
 165 //      clear_inode:
 166 };
 167
 168
 169
 170
 171
 172 static int yaffs_readlink(struct dentry *dentry, char *buffer, int buflen)
 173 {
 174         unsigned char *alias;
 175         int ret;
 176
 177         alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
 178
 179         if(!alias)
 180                 return -ENOMEM;
 181
 182         ret = vfs_readlink(dentry, buffer, buflen, alias);
 183         kfree(alias);
 184         return ret;
 185 }
 186
 187 static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd)
 188 {
 189         unsigned char *alias;
 190         int ret;
 191         alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
 192
 193         if(!alias)
 194                 return -ENOMEM;
 195
 196         ret = vfs_follow_link(nd,alias);
 197         kfree(alias);
 198         return ret;
 199 }
 200
 201
 202 struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,yaffs_Object *obj);
 203
 204 /*
 205  * Lookup is used to find objects in the fs
 206  */
 207 static struct dentry * yaffs_lookup(struct inode *dir, struct dentry *dentry)
 208 {
 209         yaffs_Object *obj;
 210         struct inode *inode;
 211
 212
 213         T((KERN_DEBUG"yaffs_lookup for %d:%s\n",yaffs_InodeToObject(dir)->objectId,dentry->d_name.name));
 214
 215         obj = yaffs_FindObjectByName(yaffs_InodeToObject(dir),dentry->d_name.name);
 216
 217         obj = yaffs_GetEquivalentObject(obj); // in case it was a hardlink
 218
 219         if(obj)
 220         {
 221                 T((KERN_DEBUG"yaffs_lookup found %d\n",obj->objectId));
 222
 223                 inode = yaffs_get_inode(dir->i_sb, obj->st_mode,0,obj);
 224
 225                 if(inode)
 226                 {
 227                         T((KERN_DEBUG"yaffs_loookup looks good\n"));
 228                         dget(dentry); // try to solve directory bug
 229                         d_add(dentry,inode);
 230                         return dentry;
 231                 }
 232
 233         }
 234         else
 235         {
 236                 T((KERN_DEBUG"yaffs_lookup not found\n"));
 237
 238         }
 239         return NULL;
 240
 241 }
 242
 243 // For now put inode is just for debugging
 244 static void yaffs_put_inode(struct inode *inode)
 245 {
 246         T(("yaffs_put_inode: ino %d, count %d\n",(int)inode->i_ino, atomic_read(&inode->i_count)));
 247
 248         // yaffs_FlushFile(yaffs_InodeToObject(inode));
 249
 250 }
 251
 252
 253 static int yaffs_file_flush(struct file* file)
 254 {
 255         yaffs_Object *obj = yaffs_DentryToObject(file->f_dentry);
 256
 257         T((KERN_DEBUG"yaffs_file_flush object %d (%s)\n",obj->objectId,
 258                                 obj->dirty ? "dirty" : "clean"));
 259
 260     yaffs_FlushFile(obj);
 261
 262     return 0;
 263 }
 264
 265
 266
 267 static int yaffs_readpage_nolock(struct file *f, struct page * pg)
 268 {
 269         // Lifted from jffs2
 270
 271         yaffs_Object *obj;
 272         unsigned char *pg_buf;
 273         int ret;
 274
 275         T((KERN_DEBUG"yaffs_readpage at %08x, size %08x\n",
 276                       pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE));
 277
 278         obj  = yaffs_DentryToObject(f->f_dentry);
 279
 280         //down(obj->sem);
 281
 282         if (!PageLocked(pg))
 283                 PAGE_BUG(pg);
 284
 285         pg_buf = kmap(pg);
 286         /* FIXME: Can kmap fail? */
 287
 288         ret = yaffs_ReadDataFromFile(obj, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);
 289
 290         if(ret >= 0) ret = 0;
 291
 292         if (ret) {
 293                 ClearPageUptodate(pg);
 294                 SetPageError(pg);
 295         } else {
 296                 SetPageUptodate(pg);
 297                 ClearPageError(pg);
 298         }
 299
 300         flush_dcache_page(pg);
 301         kunmap(pg);
 302
 303
 304
 305         //up(&obj->sem);
 306
 307         T((KERN_DEBUG"yaffs_readpage done\n"));
 308         return ret;
 309 }
 310
 311 static int yaffs_readpage_unlock(struct file *f, struct page *pg)
 312 {
 313         int ret = yaffs_readpage_nolock(f,pg);
 314         UnlockPage(pg);
 315         return ret;
 316 }
 317
 318 static int yaffs_readpage(struct file *f, struct page * pg)
 319 {
 320         return yaffs_readpage_unlock(f,pg);
 321 }
 322
 323
 324 static int yaffs_prepare_write(struct file *f, struct page *pg, unsigned offset, unsigned to)
 325 {
 326
 327         T((KERN_DEBUG"yaffs_prepair_write\n"));
 328         if(!Page_Uptodate(pg) && (offset || to < PAGE_CACHE_SIZE))
 329                 return  yaffs_readpage_nolock(f,pg);
 330
 331         return 0;
 332
 333 }
 334
 335 static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset, unsigned to)
 336 {
 337
 338         void *addr = page_address(pg) + offset;
 339         loff_t pos = (((loff_t)pg->index) << PAGE_CACHE_SHIFT) + offset;
 340         int nBytes = to - offset;
 341         int nWritten;
 342
 343         unsigned spos = pos;
 344         unsigned saddr = addr;
 345
 346         T((KERN_DEBUG"yaffs_commit_write addr %x pos %x nBytes %d\n",saddr,spos,nBytes));
 347
 348         nWritten = yaffs_file_write(f,addr, nBytes, &pos);
 349
 350         if(nWritten != nBytes)
 351         {
 352                 T((KERN_DEBUG"yaffs_commit_write not same size nWritten %d  nBytes %d\n",nWritten,nBytes));
 353                 SetPageError(pg);
 354                 ClearPageUptodate(pg);
 355         }
 356         else
 357         {
 358                 SetPageUptodate(pg);
 359         }
 360
 361         T((KERN_DEBUG"yaffs_commit_write returning %d\n",nWritten));
 362
 363         return nWritten;
 364
 365 }
 366
 367
 368
 369 static void yaffs_FillInodeFromObject(struct inode *inode, yaffs_Object *obj)
 370 {
 371         if (inode && obj)
 372         {
 373                 inode->i_ino = obj->objectId;
 374                 inode->i_mode = obj->st_mode;
 375                 inode->i_uid = obj->st_uid;
 376                 inode->i_gid = obj->st_gid;
 377                 inode->i_blksize = inode->i_sb->s_blocksize;
 378                 inode->i_blocks = 0;
 379                 inode->i_rdev = obj->st_rdev;;
 380                 inode->i_atime = obj->st_atime;
 381                 inode->i_mtime = obj->st_mtime;
 382                 inode->i_ctime = obj->st_ctime;
 383                 inode->i_size = yaffs_GetObjectFileLength(obj);
 384                 inode->i_nlink = yaffs_GetObjectLinkCount(obj);
 385
 386                 T((KERN_DEBUG"yaffs_FillInode mode %x uid %d gid %d size %d count %d\n",
 387                                 inode->i_mode, inode->i_uid, inode->i_gid, (int)inode->i_size, atomic_read(&inode->i_count)));
 388
 389                 switch (obj->st_mode & S_IFMT)
 390                 {
 391                         default: // fifo, device or socket
 392                                 init_special_inode(inode, obj->st_mode, obj->st_rdev);
 393                                 break;
 394                         case S_IFREG:   // file
 395                                 inode->i_op = &yaffs_file_inode_operations;
 396                                 inode->i_fop = &yaffs_file_operations;
 397                                 inode->i_mapping->a_ops = &yaffs_file_address_operations;
 398                                 break;
 399                         case S_IFDIR:   // directory
 400                                 inode->i_op = &yaffs_dir_inode_operations;
 401                                 inode->i_fop = &yaffs_dir_operations;
 402                                 break;
 403                         case S_IFLNK:   // symlink
 404                                 inode->i_op = &yaffs_symlink_inode_operations;
 405                                 break;
 406                 }
 407
 408
 409                 inode->u.generic_ip = obj;
 410
 411         }
 412         else
 413         {
 414                 T((KERN_DEBUG"yaffs_FileInode invalid parameters\n"));
 415         }
 416
 417 }
 418
 419 struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,yaffs_Object *obj)
 420 {
 421         struct inode * inode;
 422
 423         T((KERN_DEBUG"yaffs_get_inode for object %d\n",obj->objectId));
 424
 425         inode = iget(sb,obj->objectId);
 426
 427         // No need to call this since iget calls it via the read_inode callback
 428         // yaffs_FillInodeFromObject(inode,obj);
 429
 430         return inode;
 431 }
 432
 433 static ssize_t yaffs_file_read(struct file *f, char *buf, size_t n, loff_t *pos)
 434 {
 435         yaffs_Object *obj;
 436         int nRead,ipos;
 437         struct inode *inode;
 438
 439         T((KERN_DEBUG"yaffs_file_read\n"));
 440
 441         obj  = yaffs_DentryToObject(f->f_dentry);
 442         inode = f->f_dentry->d_inode;
 443
 444         if (*pos < inode->i_size)
 445         {
 446                         if (*pos + n > inode->i_size)
 447                         {
 448                                 n = inode->i_size - *pos;
 449                         }
 450         }
 451         else
 452         {
 453                 n = 0;
 454         }
 455
 456         nRead = yaffs_ReadDataFromFile(obj,buf,*pos,n);
 457         if(nRead > 0)
 458         {
 459                 f->f_pos += nRead;
 460         }
 461         ipos = *pos;
 462         T((KERN_DEBUG"yaffs_file_read read %d bytes, %d read at %d\n",n,nRead,ipos));
 463         return nRead;
 464
 465 }
 466
 467
 468 static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n, loff_t *pos)
 469 {
 470         yaffs_Object *obj;
 471         int nWritten,ipos;
 472         struct inode *inode;
 473
 474         obj  = yaffs_DentryToObject(f->f_dentry);
 475         inode = f->f_dentry->d_inode;
 476
 477         if(!S_ISBLK(inode->i_mode) && f->f_flags & O_APPEND)
 478         {
 479                 ipos = inode->i_size;
 480         }
 481         else
 482         {
 483                 ipos = *pos;
 484         }
 485
 486
 487         if(!obj)
 488         {
 489                 T((KERN_DEBUG"yaffs_file_write: hey obj is null!\n"));
 490         }
 491         else
 492         {
 493                 T((KERN_DEBUG"yaffs_file_write about to write writing %d bytes to object %d at %d\n",n,obj->objectId,ipos));
 494         }
 495
 496         nWritten = yaffs_WriteDataToFile(obj,buf,ipos,n);
 497
 498         T((KERN_DEBUG"yaffs_file_write writing %d bytes, %d written at %d\n",n,nWritten,ipos));
 499         if(nWritten > 0)
 500         {
 501                 ipos += nWritten;
 502                 *pos = ipos;
 503                 if(ipos > inode->i_size)
 504                 {
 505                         inode->i_size = ipos;
 506                         inode->i_blocks = (ipos + inode->i_blksize - 1)/ inode->i_blksize;
 507
 508                         T((KERN_DEBUG"yaffs_file_write size updated to %d bytes, %d blocks\n",ipos,inode->i_blocks));
 509                 }
 510
 511         }
 512         return nWritten != n ? -ENOSPC : nWritten;
 513 }
 514
 515
 516 static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir)
 517 {
 518         yaffs_Object *obj;
 519         struct inode *inode = f->f_dentry->d_inode;
 520         unsigned long offset, curoffs;
 521         struct list_head *i;
 522         yaffs_Object *l;
 523
 524         char name[YAFFS_MAX_NAME_LENGTH +1];
 525
 526         obj =  yaffs_DentryToObject(f->f_dentry);
 527
 528         offset = f->f_pos;
 529
 530         T(("yaffs_readdir: starting at %d\n",(int)offset));
 531
 532         if(offset == 0)
 533         {
 534         T((KERN_DEBUG"yaffs_readdir: entry . ino %d \n",(int)inode->i_ino));
 535                 if(filldir(dirent,".",1,offset,inode->i_ino,DT_DIR) < 0)
 536                 {
 537                         goto out;
 538                 }
 539                 offset++;
 540                 f->f_pos++;
 541         }
 542         if(offset == 1)
 543         {
 544                 T((KERN_DEBUG"yaffs_readdir: entry .. ino %d \n",(int)f->f_dentry->d_parent->d_inode->i_ino));
 545                 if(filldir(dirent,"..",2,offset,f->f_dentry->d_parent->d_inode->i_ino,DT_DIR) < 0)
 546                 {
 547                         goto out;
 548                 }
 549                 offset++;
 550                 f->f_pos++;
 551         }
 552
 553         curoffs = 1;
 554
 555         //down(&obj->sem);
 556
 557
 558         list_for_each(i,&obj->variant.directoryVariant.children)
 559         {
 560                 curoffs++;
 561                 if(curoffs >= offset)
 562                 {
 563                         l = list_entry(i, yaffs_Object,siblings);
 564
 565                         yaffs_GetObjectName(l,name,YAFFS_MAX_NAME_LENGTH+1);
 566                         T((KERN_DEBUG"yaffs_readdir: %s inode %d\n",name,yaffs_GetObjectInode(l)));
 567
 568                         if(filldir(dirent,
 569                                            name,
 570                                            strlen(name),
 571                                            offset,
 572                                            yaffs_GetObjectInode(l),
 573                                            yaffs_GetObjectType(l))
 574                                            < 0)
 575                         {
 576                                 goto up_and_out;
 577                         }
 578
 579                         offset++;
 580                         f->f_pos++;
 581                 }
 582         }
 583
 584   up_and_out:
 585
 586         //up(&obj->sem);
 587
 588   out:
 589         return 0;
 590 }
 591
 592
 593 /*
 594  * File creation. Allocate an inode, and we're done..
 595  */
 596 static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode, int dev)
 597 {
 598         struct inode *inode;
 599
 600         yaffs_Object *obj = NULL;
 601         yaffs_Object *parent = yaffs_InodeToObject(dir);
 602
 603         int error = -ENOSPC;
 604
 605         if(parent)
 606         {
 607                 T((KERN_DEBUG"yaffs_mknod: parent object %d type %d\n",
 608                                          parent->objectId,parent->variantType));
 609         }
 610         else
 611         {
 612                 T((KERN_DEBUG"yaffs_mknod: could not get parent object\n"));
 613                 return -EPERM;
 614         }
 615
 616         T(("yaffs_mknod: making oject for %s, mode %x dev %x\n",
 617                                 dentry->d_name.name, mode,dev));
 618
 619         switch (mode & S_IFMT)
 620         {
 621                 default:
 622                         // Special (socket, fifo, device...)
 623                         T((KERN_DEBUG"yaffs_mknod: making special\n"));
 624                         obj = yaffs_MknodSpecial(parent,dentry->d_name.name,mode,current->uid, current->gid,dev);
 625                         break;
 626                 case S_IFREG:   // file
 627                         T((KERN_DEBUG"yaffs_mknod: making file\n"));
 628                         obj = yaffs_MknodFile(parent,dentry->d_name.name,mode,current->uid, current->gid);
 629                         break;
 630                 case S_IFDIR:   // directory
 631                         T((KERN_DEBUG"yaffs_mknod: making directory\n"));
 632                         obj = yaffs_MknodDirectory(parent,dentry->d_name.name,mode,current->uid, current->gid);
 633                         break;
 634                 case S_IFLNK:   // symlink
 635                         T((KERN_DEBUG"yaffs_mknod: making file\n"));
 636                         obj = NULL; // Do we ever get here?
 637                         break;
 638         }
 639
 640         if(obj)
 641         {
 642                 inode = yaffs_get_inode(dir->i_sb, mode, dev, obj);
 643                 d_instantiate(dentry, inode);
 644                 T((KERN_DEBUG"yaffs_mknod created object %d count = %d\n",obj->objectId,atomic_read(&inode->i_count)));
 645                 error = 0;
 646         }
 647         else
 648         {
 649                 T((KERN_DEBUG"yaffs_mknod failed making object\n"));
 650                 error = -ENOMEM;
 651         }
 652
 653
 654         return error;
 655 }
 656
 657 static int yaffs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
 658 {
 659         int retVal;
 660         T((KERN_DEBUG"yaffs_mkdir\n"));
 661         retVal =  yaffs_mknod(dir, dentry, mode | S_IFDIR, 0);
 662 #if 0
 663  // attempt to fix dir bug - didn't work
 664         if(!retVal)
 665         {
 666                 dget(dentry);
 667         }
 668 #endif
 669         return retVal;
 670 }
 671
 672 static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode)
 673 {
 674         T((KERN_DEBUG"yaffs_create\n"));
 675         return yaffs_mknod(dir, dentry, mode | S_IFREG, 0);
 676 }
 677
 678
 679 static int yaffs_unlink(struct inode * dir, struct dentry *dentry)
 680 {
 681
 682         T((KERN_DEBUG"yaffs_unlink %d:%s\n",dir->i_ino,dentry->d_name.name));
 683
 684         if(yaffs_Unlink(yaffs_InodeToObject(dir),dentry->d_name.name) == YAFFS_OK)
 685         {
 686                 return 0;
 687         }
 688         else
 689         {
 690                 return -ENOTEMPTY;
 691         }
 692 }
 693
 694
 695 /*
 696  * Create a link...
 697  */
 698 static int yaffs_link(struct dentry *old_dentry, struct inode * dir, struct dentry * dentry)
 699 {
 700         struct inode *inode = old_dentry->d_inode;
 701         yaffs_Object *obj = NULL;
 702         yaffs_Object *link=NULL;
 703
 704         T((KERN_DEBUG"yaffs_link\n"));
 705
 706         obj = yaffs_InodeToObject(inode);
 707
 708         link = yaffs_Link(yaffs_InodeToObject(dir),dentry->d_name.name,obj);
 709
 710         if(link)
 711         {
 712                 return 0;
 713         }
 714
 715
 716         return -EPERM;
 717 }
 718
 719
 720 static int yaffs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
 721 {
 722         yaffs_Object *obj;
 723
 724         T((KERN_DEBUG"yaffs_symlink\n"));
 725
 726         obj = yaffs_MknodSymLink(yaffs_InodeToObject(dir), dentry->d_name.name,
 727                                                          S_IFLNK | S_IRWXUGO, current->uid, current->gid,
 728                                                          symname);
 729
 730         if(obj)
 731         {
 732                 T((KERN_DEBUG"symlink created OK\n"));
 733                 return 0;
 734         }
 735         else
 736         {
 737                 T((KERN_DEBUG"symlink not created\n"));
 738
 739         }
 740
 741         return -ENOMEM;
 742 }
 743
 744 static int yaffs_sync_object(struct file * file, struct dentry *dentry, int datasync)
 745 {
 746
 747         T((KERN_DEBUG"yaffs_sync_object\n"));
 748         yaffs_FlushFile(yaffs_DentryToObject(dentry));
 749         return 0;
 750 }
 751
 752 /*
 753  * The VFS layer already does all the dentry stuff for rename.
 754  */
 755 static int yaffs_rename(struct inode * old_dir, struct dentry *old_dentry, struct inode * new_dir,struct dentry *new_dentry)
 756 {
 757
 758
 759         if( yaffs_RenameObject(yaffs_InodeToObject(old_dir),old_dentry->d_name.name,
 760                                yaffs_InodeToObject(new_dir),new_dentry->d_name.name) == YAFFS_OK)
 761         {
 762                 return 0;
 763         }
 764         else
 765         {
 766                 return -ENOTEMPTY;
 767         }
 768
 769
 770 }
 771
 772 static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
 773 {
 774         struct inode *inode = dentry->d_inode;
 775         int error;
 776
 777         T((KERN_DEBUG"yaffs_setattr of object %d\n",yaffs_InodeToObject(inode)->objectId));
 778
 779         if((error = inode_change_ok(inode,attr)) == 0)
 780         {
 781
 782                 if(yaffs_SetAttributes(yaffs_InodeToObject(inode),attr) == YAFFS_OK)
 783                 {
 784                         error = 0;
 785                 }
 786                 else
 787                 {
 788                         error = -EPERM;
 789                 }
 790
 791                 inode_setattr(inode,attr);
 792         }
 793         return error;
 794 }
 795
 796 static int yaffs_statfs(struct super_block *sb, struct statfs *buf)
 797 {
 798         T((KERN_DEBUG"yaffs_statfs\n"));
 799
 800         buf->f_type = YAFFS_MAGIC;
 801         buf->f_bsize = sb->s_blocksize;
 802         buf->f_namelen = 255;
 803         buf->f_blocks = yaffs_SuperToDevice(sb)->nBlocks * YAFFS_CHUNKS_PER_BLOCK/
 804                                                 (sb->s_blocksize/YAFFS_BYTES_PER_CHUNK);
 805         buf->f_files = 0;
 806         buf->f_ffree = 0;
 807         buf->f_bfree = yaffs_GetNumberOfFreeChunks(yaffs_SuperToDevice(sb))/
 808                                                 (sb->s_blocksize/YAFFS_BYTES_PER_CHUNK);
 809         buf->f_bavail =  buf->f_bfree;
 810         return 0;
 811 }
 812
 813 static void yaffs_read_inode (struct inode *inode)
 814 {
 815
 816         yaffs_Object *obj ;
 817
 818         T((KERN_DEBUG"yaffs_read_inode for %d\n",(int)inode->i_ino));
 819
 820         obj  = yaffs_FindObjectByNumber(yaffs_SuperToDevice(inode->i_sb),inode->i_ino);
 821
 822         yaffs_FillInodeFromObject(inode,obj);
 823 }
 824
 825
 826 static void yaffs_put_super(struct super_block *sb)
 827 {
 828         yaffs_Device *dev = yaffs_SuperToDevice(sb);
 829
 830         if(dev->putSuperFunc)
 831         {
 832                  dev->putSuperFunc(sb);
 833         }
 834         yaffs_Deinitialise(dev);
 835         kfree(dev);
 836 }
 837
 838
 839 #ifdef CONFIG_YAFFS_MTD_ENABLED
 840
 841 static void  yaffs_MTDPutSuper(struct super_block *sb)
 842 {
 843
 844         struct mtd_info *mtd = yaffs_SuperToDevice(sb)->genericDevice;
 845
 846         if(mtd->sync)
 847         {
 848                 mtd->sync(mtd);
 849         }
 850
 851         put_mtd_device(mtd);
 852 }
 853
 854 #endif
 855
 856 static struct super_block *yaffs_internal_read_super(int useRam, struct super_block * sb, void * data, int silent)
 857 {
 858         struct inode * inode;
 859         struct dentry * root;
 860         yaffs_Device *dev;
 861
 862         sb->s_magic = YAFFS_MAGIC;
 863         sb->s_op = &yaffs_super_ops;
 864
 865         if(!sb)
 866                 printk(KERN_INFO"yaffs: sb is NULL\n");
 867         else if(!sb->s_dev)
 868                 printk(KERN_INFO"yaffs: sb->s_dev is NULL\n");
 869         else if(! kdevname(sb->s_dev))
 870                 printk(KERN_INFO"yaffs: kdevname is NULL\n");
 871         else
 872                 printk(KERN_INFO"yaffs: dev is %d name is \"%s\"\n", sb->s_dev, kdevname(sb->s_dev));
 873
 874
 875
 876 #ifdef CONFIG_YAFFS_USE_CHUNK_SIZE
 877         sb->s_blocksize = YAFFS_BYTES_PER_CHUNK;
 878         sb->s_blocksize_bits = YAFFS_CHUNK_SIZE_SHIFT;
 879 #else
 880         sb->s_blocksize = PAGE_CACHE_SIZE;
 881         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 882 #endif
 883         T(("yaffs_read_super: %s block size %d\n", useRam ? "RAM" : "MTD",sb->s_blocksize));
 884
 885 #ifdef CONFIG_YAFFS_DISABLE_WRITE_VERIFY
 886         T(("yaffs: Write verification disabled. All guarantees null and void\n");
 887 #endif
 888
 889
 890
 891         if(useRam)
 892         {
 893
 894 #ifdef CONFIG_YAFFS_RAM_ENABLED
 895                 // Set the yaffs_Device up for ram emulation
 896
 897                 sb->u.generic_sbp =     dev = kmalloc(sizeof(yaffs_Device),GFP_KERNEL);
 898                 if(!dev)
 899                 {
 900                         // Deep shit could not allocate device structure
 901                         printk(KERN_DEBUG"yaffs_read_super: Failed trying to allocate yaffs_Device. Terminating debug.\n");
 902                         return NULL;
 903                 }
 904
 905                 memset(dev,0,sizeof(yaffs_Device));
 906                 dev->genericDevice = NULL; // Not used for RAM emulation.
 907
 908                 dev->nBlocks = YAFFS_RAM_EMULATION_SIZE / (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK);
 909                 dev->startBlock = 1;  // Don't use block 0
 910                 dev->endBlock = dev->nBlocks - 1;
 911
 912                 dev->writeChunkToNAND = nandemul_WriteChunkToNAND;
 913                 dev->readChunkFromNAND = nandemul_ReadChunkFromNAND;
 914                 dev->eraseBlockInNAND = nandemul_EraseBlockInNAND;
 915                 dev->initialiseNAND = nandemul_InitialiseNAND;
 916
 917 #endif
 918
 919         }
 920         else
 921         {
 922 #ifdef CONFIG_YAFFS_MTD_ENABLED
 923                 struct mtd_info *mtd;
 924
 925                 printk(KERN_DEBUG "yaffs: Attempting MTD mount on %u.%u, \"%s\"\n",
 926                  MAJOR(sb->s_dev),MINOR(sb->s_dev),kdevname(sb->s_dev));
 927
 928                 // Hope it's a NAND mtd
 929                 mtd = get_mtd_device(NULL, MINOR(sb->s_dev));
 930                 if (!mtd)
 931                 {
 932                         printk(KERN_DEBUG "yaffs: MTD device #%u doesn't appear to exist\n", MINOR(sb->s_dev));
 933                         return NULL;
 934                 }
 935
 936                 if(mtd->type != MTD_NANDFLASH)
 937                 {
 938                         printk(KERN_DEBUG "yaffs: MTD device is not NAND it's type %d\n", mtd->type);
 939                         return NULL;
 940                 }
 941
 942                 printk(KERN_DEBUG" erase %x\n",mtd->erase);
 943                 printk(KERN_DEBUG" read %x\n",mtd->read);
 944                 printk(KERN_DEBUG" write %x\n",mtd->write);
 945                 printk(KERN_DEBUG" readoob %x\n",mtd->read_oob);
 946                 printk(KERN_DEBUG" writeoob %x\n",mtd->write_oob);
 947                 printk(KERN_DEBUG" oobblock %x\n",mtd->oobblock);
 948                 printk(KERN_DEBUG" oobsize %x\n",mtd->oobsize);
 949
 950
 951                 if(!mtd->erase ||
 952                    !mtd->read  ||
 953                    !mtd->write ||
 954                    !mtd->read_oob ||
 955                    !mtd->write_oob)
 956                 {
 957                         printk(KERN_DEBUG "yaffs: MTD device does not support required functions\n");
 958                         return NULL;
 959                 }
 960
 961                 if(mtd->oobblock != YAFFS_BYTES_PER_CHUNK ||
 962                    mtd->oobsize != YAFFS_BYTES_PER_SPARE)
 963                 {
 964                         printk(KERN_DEBUG "yaffs: MTD device does not support have the right page sizes\n");
 965                         return NULL;
 966                 }
 967
 968
 969                 // OK, so if we got here, we have an MTD that's NAND and looks
 970                 // like it has the right capabilities
 971                 // Set the yaffs_Device up for ram emulation
 972
 973                 sb->u.generic_sbp =     dev = kmalloc(sizeof(yaffs_Device),GFP_KERNEL);
 974                 if(!dev)
 975                 {
 976                         // Deep shit could not allocate device structure
 977                         printk(KERN_DEBUG"yaffs_read_super: Failed trying to allocate yaffs_Device. Terminating debug.\n");
 978                         return NULL;
 979                 }
 980
 981                 memset(dev,0,sizeof(yaffs_Device));
 982                 dev->genericDevice = mtd;
 983
 984                 // Set up the memory size parameters....
 985
 986 // NCB          dev->nBlocks = YAFFS_RAM_EMULATION_SIZE / (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK);
 987                 dev->nBlocks = mtd->size / (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK);
 988                 dev->startBlock = 1;  // Don't use block 0
 989                 dev->endBlock = dev->nBlocks - 1;
 990
 991                 // ... and the functions.
 992                 dev->writeChunkToNAND = nandmtd_WriteChunkToNAND;
 993                 dev->readChunkFromNAND = nandmtd_ReadChunkFromNAND;
 994                 dev->eraseBlockInNAND = nandmtd_EraseBlockInNAND;
 995                 dev->initialiseNAND = nandmtd_InitialiseNAND;
 996
 997                 dev->putSuperFunc = yaffs_MTDPutSuper;
 998 #endif
 999         }
1000
1001
1002
1003         yaffs_GutsInitialise(yaffs_SuperToDevice(sb));
1004         T(("yaffs_read_super: guts initialised\n"));
1005
1006         // Create root inode
1007         inode = yaffs_get_inode(sb, S_IFDIR | 0755, 0,yaffs_Root(yaffs_SuperToDevice(sb)));
1008         if (!inode)
1009                 return NULL;
1010
1011         T(("yaffs_read_super: got root inode\n"));
1012
1013
1014         root = d_alloc_root(inode);
1015
1016         T(("yaffs_read_super: d_alloc_root done\n"));
1017
1018         if (!root) {
1019                 iput(inode);
1020                 return NULL;
1021         }
1022         sb->s_root = root;
1023
1024         T(("yaffs_read_super: done\n"));
1025         return sb;
1026 }
1027
1028 #ifdef CONFIG_YAFFS_MTD_ENABLED
1029 static struct super_block *yaffs_read_super(struct super_block * sb, void * data, int silent)
1030 {
1031         return yaffs_internal_read_super(0,sb,data,silent);
1032 }
1033
1034 static DECLARE_FSTYPE(yaffs_fs_type, "yaffs", yaffs_read_super, FS_REQUIRES_DEV);
1035 #endif
1036
1037 #ifdef CONFIG_YAFFS_RAM_ENABLED
1038
1039 static struct super_block *yaffs_ram_read_super(struct super_block * sb, void * data, int silent)
1040 {
1041         return yaffs_internal_read_super(1,sb,data,silent);
1042 }
1043
1044 static DECLARE_FSTYPE(yaffs_ram_fs_type, "yaffsram", yaffs_ram_read_super, FS_SINGLE);
1045 #endif // CONFIG_YAFFS_RAM_ENABLED
1046
1047
1048 static struct proc_dir_entry *my_proc_entry;
1049
1050
1051 static int  yaffs_proc_read(
1052         char *page,
1053         char **start,
1054         off_t offset,
1055         int count,
1056         int *eof,
1057         void *data
1058         )
1059 {
1060
1061         static char my_buffer[1000];
1062
1063         if (offset > 0) return 0;
1064
1065         /* Fill the buffer and get its length */
1066         sprintf( my_buffer,
1067                 "YAFFS built:"__DATE__ " "__TIME__"\n"
1068
1069         );
1070
1071         strcpy(page,my_buffer);
1072         return strlen(my_buffer);
1073 }
1074
1075 static int __init init_yaffs_fs(void)
1076 {
1077         int error = 0;
1078
1079         printk(KERN_DEBUG "yaffs " __DATE__ " " __TIME__ " Initialisation\n");
1080 #ifdef CONFIG_YAFFS_USE_GENERIC_RW
1081         printk(KERN_DEBUG "yaffs is using generic read/write (caching)\n");
1082 #else
1083         printk(KERN_DEBUG "yaffs is using direct read/write (uncached)\n");
1084 #endif
1085
1086
1087     /* Install the proc_fs entry */
1088     my_proc_entry = create_proc_read_entry("yaffs",
1089                                            S_IRUGO | S_IFREG,
1090                                            &proc_root,
1091                                            yaffs_proc_read,
1092                                            NULL);
1093     if(!my_proc_entry)
1094     {
1095        return -ENOMEM;
1096     }
1097
1098 #ifdef CONFIG_YAFFS_RAM_ENABLED
1099
1100     error = register_filesystem(&yaffs_ram_fs_type);
1101     if(error)
1102     {
1103         return error;
1104     }
1105 #endif //CONFIG_YAFFS_RAM_ENABLED
1106
1107 #ifdef CONFIG_YAFFS_MTD_ENABLED
1108         error = register_filesystem(&yaffs_fs_type);
1109         if(error)
1110         {
1111 #ifdef CONFIG_YAFFS_RAM_ENABLED
1112                 unregister_filesystem(&yaffs_ram_fs_type);
1113 #endif //CONFIG_YAFFS_RAM_ENABLED
1114         }
1115 #endif // CONFIG_YAFFS_MTD_ENABLED
1116
1117         return error;
1118 }
1119
1120 static void __exit exit_yaffs_fs(void)
1121 {
1122         printk(KERN_DEBUG "yaffs " __DATE__ " " __TIME__ " Clean up\n");
1123
1124     remove_proc_entry("yaffs",&proc_root);
1125
1126 #ifdef CONFIG_YAFFS_RAM_ENABLED
1127         unregister_filesystem(&yaffs_ram_fs_type);
1128 #endif
1129 #ifdef CONFIG_YAFFS_MTD_ENABLED
1130         unregister_filesystem(&yaffs_fs_type);
1131 #endif
1132
1133 }
1134
1135 module_init(init_yaffs_fs)
1136 module_exit(exit_yaffs_fs)
1137
1138 MODULE_DESCRIPTION("YAFFS - a NAND specific flash file system");
1139 MODULE_AUTHOR("Charles Manning, Aleph One Ltd., 2002");
1140 MODULE_LICENSE("GPL");
1141