Clean up field assignments
[yaffs2.git] / yaffs_fs.c
index 7b4a8b04c65ef57a635fa2564e03acc3666e87a8..775f3e878c6eda9b6c257c82c5c62f181da80b92 100644 (file)
@@ -15,7 +15,8 @@
  * the VFS.
  *
  * Special notes: 
- * >> sb->u.generic_sbp points to the yaffs_Device associated with this superblock
+ * >> 2.4: sb->u.generic_sbp points to the yaffs_Device associated with this superblock
+ * >> 2.6: sb->s_fs_info  points to the yaffs_Device associated with this superblock
  * >> inode->u.generic_ip points to the associated yaffs_Object.
  *
  *
@@ -29,7 +30,7 @@
  */
 
 
-const char *yaffs_fs_c_version = "$Id: yaffs_fs.c,v 1.5 2005-04-29 07:01:18 charles Exp $";
+const char *yaffs_fs_c_version = "$Id: yaffs_fs.c,v 1.12 2005-07-27 20:23:15 charles Exp $";
 extern const char *yaffs_guts_c_version;
 
 
@@ -43,6 +44,7 @@ extern const char *yaffs_guts_c_version;
 #include <linux/list.h>
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
+#include <linux/smp_lock.h>
 #include <linux/pagemap.h>
 #include <linux/mtd/mtd.h>
 #include <linux/interrupt.h>
@@ -164,75 +166,70 @@ static void yaffs_delete_inode(struct inode *);
 static void yaffs_clear_inode(struct inode *);
 
 static int yaffs_readpage(struct file *file, struct page * page);
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
+static int yaffs_writepage(struct page *page, struct writeback_control *wbc);
+#else
 static int yaffs_writepage(struct page *page);
+#endif
 static int yaffs_prepare_write(struct file *f, struct page *pg, unsigned offset, unsigned to);
 static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset, unsigned to);
 
-static int yaffs_readlink(struct dentry *dentry, char *buffer, int buflen);
+static int yaffs_readlink(struct dentry *dentry, char __user *buffer, int buflen);
 static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
 
 
 
-
 static struct address_space_operations yaffs_file_address_operations = {
-       readpage:               yaffs_readpage,
-       writepage:              yaffs_writepage,
-       prepare_write:  yaffs_prepare_write,
-       commit_write:   yaffs_commit_write
+       .readpage       = yaffs_readpage,
+       .writepage      = yaffs_writepage,
+       .prepare_write  = yaffs_prepare_write,
+       .commit_write   = yaffs_commit_write,
 };
 
-
 static struct file_operations yaffs_file_operations = {
-
-       read:           generic_file_read,
-       write:          generic_file_write,
-
-       mmap:           generic_file_mmap,
-       flush:          yaffs_file_flush,
-       fsync:          yaffs_sync_object,
+       .read           = generic_file_read,
+       .write          = generic_file_write,
+       .mmap           = generic_file_mmap,
+       .flush          = yaffs_file_flush,
+       .fsync          = yaffs_sync_object,
 };
 
-
 static struct inode_operations yaffs_file_inode_operations = {
-       setattr:        yaffs_setattr,
+       .setattr        = yaffs_setattr,
 };
 
-
-struct inode_operations yaffs_symlink_inode_operations =
-{      
-       readlink:       yaffs_readlink,
-       follow_link:    yaffs_follow_link,
-       setattr:        yaffs_setattr
+struct inode_operations yaffs_symlink_inode_operations = {     
+       .readlink       = yaffs_readlink,
+       .follow_link    = yaffs_follow_link,
+       .setattr        = yaffs_setattr,
 };
 
 static struct inode_operations yaffs_dir_inode_operations = {
-       create:         yaffs_create,
-       lookup:         yaffs_lookup,
-       link:           yaffs_link,
-       unlink:         yaffs_unlink,   
-       symlink:        yaffs_symlink,
-       mkdir:          yaffs_mkdir,
-       rmdir:          yaffs_unlink,
-       mknod:          yaffs_mknod,
-       rename:         yaffs_rename,
-       setattr:        yaffs_setattr,
+       .create         = yaffs_create,
+       .lookup         = yaffs_lookup,
+       .link           = yaffs_link,
+       .unlink         = yaffs_unlink, 
+       .symlink        = yaffs_symlink,
+       .mkdir          = yaffs_mkdir,
+       .rmdir          = yaffs_unlink,
+       .mknod          = yaffs_mknod,
+       .rename         = yaffs_rename,
+       .setattr        = yaffs_setattr,
 };
 
 static struct file_operations yaffs_dir_operations = {
-       read:           generic_read_dir,
-       readdir:        yaffs_readdir,
-       fsync:          yaffs_sync_object,
+       .read           = generic_read_dir,
+       .readdir        = yaffs_readdir,
+       .fsync          = yaffs_sync_object,
 };
 
-
 static struct super_operations yaffs_super_ops = {
-       statfs:                 yaffs_statfs,
-       read_inode:             yaffs_read_inode,
-       put_inode:              yaffs_put_inode,
-       put_super:              yaffs_put_super,
-//     remount_fs:
-       delete_inode:           yaffs_delete_inode,
-       clear_inode:            yaffs_clear_inode,
+       .statfs         = yaffs_statfs,
+       .read_inode     = yaffs_read_inode,
+       .put_inode      = yaffs_put_inode,
+       .put_super      = yaffs_put_super,
+       .delete_inode   = yaffs_delete_inode,
+       .clear_inode    = yaffs_clear_inode,
 };
 
 
@@ -251,7 +248,7 @@ static void yaffs_GrossUnlock(yaffs_Device *dev)
 
 }
 
-static int yaffs_readlink(struct dentry *dentry, char *buffer, int buflen)
+static int yaffs_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 {
        unsigned char *alias;
        int ret;
@@ -329,7 +326,7 @@ static struct dentry * yaffs_lookup(struct inode *dir, struct dentry *dentry)
        {
                T(YAFFS_TRACE_OS,(KERN_DEBUG"yaffs_lookup found %d\n",obj->objectId));
                
-               inode = yaffs_get_inode(dir->i_sb, obj->st_mode,0,obj);
+               inode = yaffs_get_inode(dir->i_sb, obj->yst_mode,0,obj);
                
                if(inode)
                {
@@ -462,8 +459,12 @@ static int yaffs_readpage_nolock(struct file *f, struct page * pg)
        dev = obj->myDev;
        
        
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
+        BUG_ON(!PageLocked(pg));
+#else
        if (!PageLocked(pg))
                 PAGE_BUG(pg);
+#endif
 
        pg_buf = kmap(pg);
        /* FIXME: Can kmap fail? */
@@ -507,7 +508,11 @@ static int yaffs_readpage(struct file *f, struct page * pg)
 // writepage inspired by/stolen from smbfs
 //
 
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
+static int yaffs_writepage(struct page *page, struct writeback_control *wbc)
+#else
 static int yaffs_writepage(struct page *page)
+#endif
 {
        struct address_space *mapping = page->mapping;
        struct inode *inode;
@@ -548,7 +553,7 @@ static int yaffs_writepage(struct page *page)
        yaffs_GrossLock(obj->myDev);
 
 
-       nWritten = yaffs_WriteDataToFile(obj,buffer,page->index << PAGE_CACHE_SHIFT,nBytes);
+       nWritten = yaffs_WriteDataToFile(obj,buffer,page->index << PAGE_CACHE_SHIFT,nBytes,0);
 
        yaffs_GrossUnlock(obj->myDev);
        
@@ -612,25 +617,25 @@ static void yaffs_FillInodeFromObject(struct inode *inode, yaffs_Object *obj)
        if (inode && obj) 
        {
                inode->i_ino = obj->objectId;
-               inode->i_mode = obj->st_mode;
-               inode->i_uid = obj->st_uid;
-               inode->i_gid = obj->st_gid;
+               inode->i_mode = obj->yst_mode;
+               inode->i_uid = obj->yst_uid;
+               inode->i_gid = obj->yst_gid;
                inode->i_blksize = inode->i_sb->s_blocksize;
 //#if defined(CONFIG_KERNEL_2_5)
 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
 
-               inode->i_rdev = old_decode_dev(obj->st_rdev);
-               inode->i_atime.tv_sec = (time_t)(obj->st_atime);
+               inode->i_rdev = old_decode_dev(obj->yst_rdev);
+               inode->i_atime.tv_sec = (time_t)(obj->yst_atime);
                inode->i_atime.tv_nsec = 0;
-               inode->i_mtime.tv_sec = (time_t)obj->st_mtime;
+               inode->i_mtime.tv_sec = (time_t)obj->yst_mtime;
                inode->i_mtime.tv_nsec =0;
-               inode->i_ctime.tv_sec = (time_t)obj->st_ctime;
+               inode->i_ctime.tv_sec = (time_t)obj->yst_ctime;
                inode->i_ctime.tv_nsec = 0;
 #else
-               inode->i_rdev = obj->st_rdev;
-               inode->i_atime = obj->st_atime;
-               inode->i_mtime = obj->st_mtime;
-               inode->i_ctime = obj->st_ctime;
+               inode->i_rdev = obj->yst_rdev;
+               inode->i_atime = obj->yst_atime;
+               inode->i_mtime = obj->yst_mtime;
+               inode->i_ctime = obj->yst_ctime;
 #endif
                inode->i_size = yaffs_GetObjectFileLength(obj);
                inode->i_blocks = (inode->i_size + 511) >> 9;
@@ -640,14 +645,15 @@ static void yaffs_FillInodeFromObject(struct inode *inode, yaffs_Object *obj)
                T(YAFFS_TRACE_OS,(KERN_DEBUG"yaffs_FillInode mode %x uid %d gid %d size %d count %d\n",
                                inode->i_mode, inode->i_uid, inode->i_gid, (int)inode->i_size, atomic_read(&inode->i_count)));
                
-               switch (obj->st_mode & S_IFMT) 
+               switch (obj->yst_mode & S_IFMT) 
                {
                        default: // fifo, device or socket
 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
-                               init_special_inode(inode, obj->st_mode,old_decode_dev(obj->st_rdev));
+                               init_special_inode(inode, obj->yst_mode,old_decode_dev(obj->yst_rdev));
 #else
-                                 init_special_inode(inode, obj->st_mode,(dev_t)(obj->st_rdev));
-#endif                         break;
+                                 init_special_inode(inode, obj->yst_mode,(dev_t)(obj->yst_rdev));
+#endif                         
+                        break;
                        case S_IFREG:   // file         
                                inode->i_op = &yaffs_file_inode_operations;
                                inode->i_fop = &yaffs_file_operations;
@@ -786,7 +792,7 @@ static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n, loff_
                T(YAFFS_TRACE_OS,(KERN_DEBUG"yaffs_file_write about to write writing %d bytes to object %d at %d\n",n,obj->objectId,ipos));
        }
 
-       nWritten = yaffs_WriteDataToFile(obj,buf,ipos,n);
+       nWritten = yaffs_WriteDataToFile(obj,buf,ipos,n,0);
 
        T(YAFFS_TRACE_OS,(KERN_DEBUG"yaffs_file_write writing %d bytes, %d written at %d\n",n,nWritten,ipos));
        if(nWritten > 0)
@@ -933,7 +939,8 @@ static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode, int r
                         obj = yaffs_MknodSpecial(parent,dentry->d_name.name,mode,current->uid, current->gid,old_encode_dev(rdev));
 #else
                         obj = yaffs_MknodSpecial(parent,dentry->d_name.name,mode,current->uid, current->gid,rdev);
-#endif                 break;
+#endif                 
+                break;
                case S_IFREG:   // file         
                        T(YAFFS_TRACE_OS,(KERN_DEBUG"yaffs_mknod: making file\n"));
                        obj = yaffs_MknodFile(parent,dentry->d_name.name,mode,current->uid, current->gid);
@@ -1091,7 +1098,7 @@ static int yaffs_symlink(struct inode * dir, struct dentry *dentry, const char *
 
                struct inode* inode;
        
-               inode = yaffs_get_inode(dir->i_sb, obj->st_mode, 0, obj);
+               inode = yaffs_get_inode(dir->i_sb, obj->yst_mode, 0, obj);
                d_instantiate(dentry, inode);
                T(YAFFS_TRACE_OS,(KERN_DEBUG"symlink created OK\n"));
                return 0;
@@ -1200,7 +1207,8 @@ static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
                        error = -EPERM;
                }
                yaffs_GrossUnlock(dev);
-               inode_setattr(inode,attr);
+               if (!error)
+                       error = inode_setattr(inode,attr);
        }
        return error;
 }
@@ -1263,14 +1271,7 @@ static void yaffs_read_inode (struct inode *inode)
 
 }
 
-
-
-// Todo
-// Currently we only can report a single partition. Need to use lists here
-static yaffs_Device *yaffs_dev;
-static yaffs_Device *yaffsram_dev;
-
-
+static LIST_HEAD(yaffs_dev_list);
 
 static void yaffs_put_super(struct super_block *sb)
 {
@@ -1284,9 +1285,9 @@ static void yaffs_put_super(struct super_block *sb)
        yaffs_Deinitialise(dev);
        yaffs_GrossUnlock(dev);
 
-       if(dev == yaffs_dev) yaffs_dev = NULL;
-       if(dev == yaffsram_dev) yaffsram_dev = NULL;
-               
+       /* we assume this is protected by lock_kernel() in mount/umount */
+       list_del(&dev->devList);
+
        kfree(dev);
 }
 
@@ -1314,7 +1315,7 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
        int nBlocks;
        struct inode * inode = NULL;
        struct dentry * root;
-       yaffs_Device *dev;
+       yaffs_Device *dev = 0;
        int err;
        
        sb->s_magic = YAFFS_MAGIC;
@@ -1353,7 +1354,13 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
 #ifdef CONFIG_YAFFS_RAM_ENABLED
                // Set the yaffs_Device up for ram emulation
 
+               
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
+               sb->s_fs_info = dev = kmalloc(sizeof(yaffs_Device),GFP_KERNEL);
+#else
                sb->u.generic_sbp = dev = kmalloc(sizeof(yaffs_Device),GFP_KERNEL);
+#endif
+
                if(!dev)
                {
                        // Deep shit could not allocate device structure
@@ -1363,9 +1370,10 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
 
                memset(dev,0,sizeof(yaffs_Device));
                dev->genericDevice = NULL; // Not used for RAM emulation.
+               dev->name = sb->s_type->name;
 
                nBlocks = YAFFS_RAM_EMULATION_SIZE / (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK);
-               dev->startBlock = 1;  // Don't use block 0
+               dev->startBlock = 0;  
                dev->endBlock = nBlocks - 1;
                dev->nChunksPerBlock = YAFFS_CHUNKS_PER_BLOCK;
                dev->nBytesPerChunk = YAFFS_BYTES_PER_CHUNK;
@@ -1383,7 +1391,7 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
                        dev->nChunksPerBlock = nandemul2k_GetChunksPerBlock();
                        dev->nBytesPerChunk =  nandemul2k_GetBytesPerChunk();;
                        nBlocks = nandemul2k_GetNumberOfBlocks();
-                       dev->startBlock = 1;  // Don't use block 0
+                       dev->startBlock = 0;
                        dev->endBlock = nBlocks - 1;
                }
                else
@@ -1394,9 +1402,6 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
                        dev->initialiseNAND = nandemul_InitialiseNAND;
                        dev->isYaffs2 = 0;
                }
-               
-               yaffsram_dev = dev;
-               
 #endif
 
        }
@@ -1429,13 +1434,13 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
                        return NULL;
                }
 
-               T(YAFFS_TRACE_OS,(" erase %x\n",mtd->erase));
-               T(YAFFS_TRACE_OS,(" read %x\n",mtd->read));
-               T(YAFFS_TRACE_OS,(" write %x\n",mtd->write));
-               T(YAFFS_TRACE_OS,(" readoob %x\n",mtd->read_oob));
-               T(YAFFS_TRACE_OS,(" writeoob %x\n",mtd->write_oob));
-               T(YAFFS_TRACE_OS,(" block_isbad %x\n",mtd->block_isbad));
-               T(YAFFS_TRACE_OS,(" block_markbad %x\n",mtd->block_markbad));
+               T(YAFFS_TRACE_OS,(" erase %p\n",mtd->erase));
+               T(YAFFS_TRACE_OS,(" read %p\n",mtd->read));
+               T(YAFFS_TRACE_OS,(" write %p\n",mtd->write));
+               T(YAFFS_TRACE_OS,(" readoob %p\n",mtd->read_oob));
+               T(YAFFS_TRACE_OS,(" writeoob %p\n",mtd->write_oob));
+               T(YAFFS_TRACE_OS,(" block_isbad %p\n",mtd->block_isbad));
+               T(YAFFS_TRACE_OS,(" block_markbad %p\n",mtd->block_markbad));
                T(YAFFS_TRACE_OS,(" oobblock %d\n",mtd->oobblock));
                T(YAFFS_TRACE_OS,(" oobsize %d\n",mtd->oobsize));
                T(YAFFS_TRACE_OS,(" erasesize %d\n",mtd->erasesize));
@@ -1511,11 +1516,12 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
 
                memset(dev,0,sizeof(yaffs_Device));
                dev->genericDevice = mtd; 
+               dev->name = mtd->name;
 
                // Set up the memory size parameters....
                
                nBlocks = mtd->size / (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK);
-               dev->startBlock = 1;  // Don't use block 0
+               dev->startBlock = 0;
                dev->endBlock = nBlocks - 1;
                dev->nChunksPerBlock = YAFFS_CHUNKS_PER_BLOCK;
                dev->nBytesPerChunk = YAFFS_BYTES_PER_CHUNK;
@@ -1535,7 +1541,7 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
                        dev->nBytesPerChunk = mtd->oobblock;
                        dev->nChunksPerBlock = mtd->erasesize / mtd->oobblock;
                        nBlocks = mtd->size / mtd->erasesize;
-                       dev->startBlock = 1;  // Don't use block 0
+                       dev->startBlock = 0;
                        dev->endBlock = nBlocks - 1;
                }
                else
@@ -1553,12 +1559,12 @@ static struct super_block *yaffs_internal_read_super(int yaffsVersion,int useRam
 #ifdef CONFIG_YAFFS_USE_NANDECC
                dev->useNANDECC = 1;
 #endif
-
-               yaffs_dev = dev;
-               
 #endif
        }
 
+       /* we assume this is protected by lock_kernel() in mount/umount */
+       list_add_tail(&dev->devList, &yaffs_dev_list);
+
        init_MUTEX(&dev->grossLock);
        
        
@@ -1686,7 +1692,7 @@ static DECLARE_FSTYPE(yaffs2_fs_type, "yaffs2", yaffs2_read_super, FS_REQUIRES_D
 static struct super_block *yaffs_ram_read_super(struct file_system_type * fs, int flags, const char *dev_name, void *data)
 {
 
-    return get_sb_bdev(fs, flags, dev_name, data, yaffs_internal_read_super_ram);
+    return get_sb_nodev(fs, flags, data, yaffs_internal_read_super_ram);
 }
 
 
@@ -1694,9 +1700,8 @@ static struct file_system_type yaffs_ram_fs_type = {
        .owner          = THIS_MODULE,
        .name           = "yaffsram",
        .get_sb         = yaffs_ram_read_super,
-       .kill_sb        = kill_block_super,
-//     .kill_sb        = kill_litter_super,
-       .fs_flags       = FS_SINGLE,
+       .kill_sb        = kill_litter_super,
+       .fs_flags       = 0 ,
 };
 #else
 static struct super_block *yaffs_ram_read_super(struct super_block * sb, void * data, int silent)
@@ -1715,7 +1720,7 @@ static DECLARE_FSTYPE(yaffs_ram_fs_type, "yaffsram", yaffs_ram_read_super, FS_SI
 static struct super_block *yaffs2_ram_read_super(struct file_system_type * fs, int flags, const char *dev_name, void *data)
 {
 
-    return get_sb_bdev(fs, flags, dev_name, data, yaffs2_internal_read_super_ram);
+    return get_sb_nodev(fs, flags, data, yaffs2_internal_read_super_ram);
 }
 
 
@@ -1723,9 +1728,8 @@ static struct file_system_type yaffs2_ram_fs_type = {
        .owner          = THIS_MODULE,
        .name           = "yaffs2ram",
        .get_sb         = yaffs2_ram_read_super,
-       .kill_sb        = kill_block_super,
-//     .kill_sb        = kill_litter_super,
-       .fs_flags       = FS_SINGLE,
+       .kill_sb        = kill_litter_super,
+       .fs_flags       = 0 ,
 };
 #else
 static struct super_block *yaffs2_ram_read_super(struct super_block * sb, void * data, int silent)
@@ -1743,9 +1747,8 @@ static DECLARE_FSTYPE(yaffs2_ram_fs_type, "yaffs2ram", yaffs2_ram_read_super, FS
 static struct proc_dir_entry *my_proc_entry;
 static struct proc_dir_entry *my_proc_ram_write_entry;
 
-static char * yaffs_dump_dev(char *buf,yaffs_Device *dev,char *name)
+static char * yaffs_dump_dev(char *buf,yaffs_Device *dev)
 {
-       buf +=sprintf(buf,"\nDevice %s\n",name);
        buf +=sprintf(buf,"startBlock......... %d\n",dev->startBlock);
        buf +=sprintf(buf,"endBlock........... %d\n",dev->endBlock);
        buf +=sprintf(buf,"chunkGroupBits..... %d\n",dev->chunkGroupBits);
@@ -1775,7 +1778,6 @@ static char * yaffs_dump_dev(char *buf,yaffs_Device *dev,char *name)
        buf +=sprintf(buf,"useNANDECC......... %d\n",dev->useNANDECC);
        buf +=sprintf(buf,"isYaffs2........... %d\n",dev->isYaffs2);
 
-       
        return buf;     
 }
 
@@ -1788,25 +1790,44 @@ static int  yaffs_proc_read(
        void *data
        )
 {
+       struct list_head *item;
+       char *buf = page;
+       int step = offset;
+       int n = 0;
+
+       /* Get proc_file_read() to step 'offset' by one on each sucessive call.
+        * We use 'offset' (*ppos) to indicate where we are in devList.
+        * This also assumes the user has posted a read buffer large
+        * enough to hold the complete output; but that's life in /proc.
+        */
+
+       *(int *)start = 1;
+
+       /* Print header first */
+       if (step == 0) {
+               buf += sprintf(buf, "YAFFS built:" __DATE__ " "__TIME__
+               "\n%s\n%s\n", yaffs_fs_c_version, yaffs_guts_c_version);
+       }
 
-       char my_buffer[3000];
-       char *buf;
-       buf = my_buffer;
-
-       if (offset > 0) return 0;
+       /* hold lock_kernel while traversing yaffs_dev_list */
+       lock_kernel();
 
-       /* Fill the buffer and get its length */
-       buf +=sprintf(buf,"YAFFS built:"__DATE__ " "__TIME__"\n%s\n%s\n", yaffs_fs_c_version,yaffs_guts_c_version);
-       
-       if(yaffs_dev) buf = yaffs_dump_dev(buf,yaffs_dev,"yaffs");
-       if(yaffsram_dev) buf = yaffs_dump_dev(buf,yaffsram_dev,"yaffsram");
-       
+       /* Locate and print the Nth entry.  Order N-squared but N is small. */
+       list_for_each(item, &yaffs_dev_list) {
+               yaffs_Device *dev = list_entry(item, yaffs_Device, devList);
+               if (n < step) {
+                       n++;
+                       continue;
+               }
+               buf += sprintf(buf,"\nDevice %d \"%s\"\n", n, dev->name);
+               buf = yaffs_dump_dev(buf, dev);
+               break;
+       }
+       unlock_kernel();
 
-       strcpy(page,my_buffer);
-       return strlen(my_buffer);
+       return buf-page < count ? buf-page : count;
 }
 
-
 static int  yaffs_proc_ram_write(
         char *page,
        char **start,
@@ -1852,8 +1873,6 @@ static int __init init_yaffs_fs(void)
        int error = 0;
        struct file_system_to_install *fsinst;  
        
-       yaffs_dev = yaffsram_dev = NULL;
-       
    T(YAFFS_TRACE_ALWAYS,("yaffs " __DATE__ " " __TIME__ " Installing. \n"));