inode.c

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	/* either due to i/o error or a stale NFS handle */
	iput (inode);
	inode = 0;
    }
    return inode;
}

struct dentry *reiserfs_fh_to_dentry(struct super_block *sb, __u32 *data,
				     int len, int fhtype, int parent) {
    struct cpu_key key ;
    struct inode *inode = NULL ;
    struct list_head *lp;
    struct dentry *result;

    /* fhtype happens to reflect the number of u32s encoded.
     * due to a bug in earlier code, fhtype might indicate there
     * are more u32s then actually fitted.
     * so if fhtype seems to be more than len, reduce fhtype.
     * Valid types are:
     *   2 - objectid + dir_id - legacy support
     *   3 - objectid + dir_id + generation
     *   4 - objectid + dir_id + objectid and dirid of parent - legacy
     *   5 - objectid + dir_id + generation + objectid and dirid of parent
     *   6 - as above plus generation of directory
     * 6 does not fit in NFSv2 handles
     */
    if (fhtype > len) {
	    if (fhtype != 6 || len != 5)
		    printk(KERN_WARNING "nfsd/reiserfs, fhtype=%d, len=%d - odd\n",
			   fhtype, len);
	    fhtype = 5;
    }
    if (fhtype < 2 || (parent && fhtype < 4)) 
	goto out ;

    if (! parent) {
	    /* this works for handles from old kernels because the default
	    ** reiserfs generation number is the packing locality.
	    */
	    key.on_disk_key.k_objectid = data[0] ;
	    key.on_disk_key.k_dir_id = data[1] ;
	    inode = reiserfs_iget(sb, &key) ;
	    if (inode && !IS_ERR(inode) && (fhtype == 3 || fhtype >= 5) &&
		data[2] != inode->i_generation) {
		    iput(inode) ;
		    inode = NULL ;
	    }
    } else {
	    key.on_disk_key.k_objectid = data[fhtype>=5?3:2] ;
	    key.on_disk_key.k_dir_id = data[fhtype>=5?4:3] ;
	    inode = reiserfs_iget(sb, &key) ;
	    if (inode && !IS_ERR(inode) && fhtype == 6 &&
		data[5] != inode->i_generation) {
		    iput(inode) ;
		    inode = NULL ;
	    }
    }
out:
    if (IS_ERR(inode))
	return ERR_PTR(PTR_ERR(inode));
    if (!inode)
        return ERR_PTR(-ESTALE) ;

    /* now to find a dentry.
     * If possible, get a well-connected one
     */
    spin_lock(&dcache_lock);
    for (lp = inode->i_dentry.next; lp != &inode->i_dentry ; lp=lp->next) {
	    result = list_entry(lp,struct dentry, d_alias);
	    if (! (result->d_flags & DCACHE_NFSD_DISCONNECTED)) {
		    dget_locked(result);
		    result->d_vfs_flags |= DCACHE_REFERENCED;
		    spin_unlock(&dcache_lock);
		    iput(inode);
		    return result;
	    }
    }
    spin_unlock(&dcache_lock);
    result = d_alloc_root(inode);
    if (result == NULL) {
	    iput(inode);
	    return ERR_PTR(-ENOMEM);
    }
    result->d_flags |= DCACHE_NFSD_DISCONNECTED;
    return result;

}

int reiserfs_dentry_to_fh(struct dentry *dentry, __u32 *data, int *lenp, int need_parent) {
    struct inode *inode = dentry->d_inode ;
    int maxlen = *lenp;
    
    if (maxlen < 3)
        return 255 ;

    data[0] = inode->i_ino ;
    data[1] = le32_to_cpu(INODE_PKEY (inode)->k_dir_id) ;
    data[2] = inode->i_generation ;
    *lenp = 3 ;
    /* no room for directory info? return what we've stored so far */
    if (maxlen < 5 || ! need_parent)
        return 3 ;

    inode = dentry->d_parent->d_inode ;
    data[3] = inode->i_ino ;
    data[4] = le32_to_cpu(INODE_PKEY (inode)->k_dir_id) ;
    *lenp = 5 ;
    if (maxlen < 6)
	    return 5 ;
    data[5] = inode->i_generation ;
    *lenp = 6 ;
    return 6 ;
}


//
// initially this function was derived from minix or ext2's analog and
// evolved as the prototype did
//
/* looks for stat data, then copies fields to it, marks the buffer
   containing stat data as dirty */
/* reiserfs inodes are never really dirty, since the dirty inode call
** always logs them.  This call allows the VFS inode marking routines
** to properly mark inodes for datasync and such, but only actually
** does something when called for a synchronous update.
*/
void reiserfs_write_inode (struct inode * inode, int do_sync) {
    struct reiserfs_transaction_handle th ;
    int jbegin_count = 1 ;

    if (inode->i_sb->s_flags & MS_RDONLY) {
        reiserfs_warning("clm-6005: writing inode %lu on readonly FS\n", 
	                  inode->i_ino) ;
        return ;
    }
    /* memory pressure can sometimes initiate write_inode calls with sync == 1,
    ** these cases are just when the system needs ram, not when the 
    ** inode needs to reach disk for safety, and they can safely be
    ** ignored because the altered inode has already been logged.
    */
    if (do_sync && !(current->flags & PF_MEMALLOC)) {
	lock_kernel() ;
	journal_begin(&th, inode->i_sb, jbegin_count) ;
	reiserfs_update_sd (&th, inode);
	journal_end_sync(&th, inode->i_sb, jbegin_count) ;
	unlock_kernel() ;
    }
}

/* FIXME: no need any more. right? */
int reiserfs_sync_inode (struct reiserfs_transaction_handle *th, struct inode * inode)
{
  int err = 0;

  reiserfs_update_sd (th, inode);
  return err;
}


/* stat data of new object is inserted already, this inserts the item
   containing "." and ".." entries */
static int reiserfs_new_directory (struct reiserfs_transaction_handle *th, 
				   struct item_head * ih, struct path * path,
				   const struct inode * dir)
{
    struct super_block * sb = th->t_super;
    char empty_dir [EMPTY_DIR_SIZE];
    char * body = empty_dir;
    struct cpu_key key;
    int retval;
    
    _make_cpu_key (&key, KEY_FORMAT_3_5, le32_to_cpu (ih->ih_key.k_dir_id),
		   le32_to_cpu (ih->ih_key.k_objectid), DOT_OFFSET, TYPE_DIRENTRY, 3/*key length*/);
    
    /* compose item head for new item. Directories consist of items of
       old type (ITEM_VERSION_1). Do not set key (second arg is 0), it
       is done by reiserfs_new_inode */
    if (old_format_only (sb)) {
	make_le_item_head (ih, 0, KEY_FORMAT_3_5, DOT_OFFSET, TYPE_DIRENTRY, EMPTY_DIR_SIZE_V1, 2);
	
	make_empty_dir_item_v1 (body, ih->ih_key.k_dir_id, ih->ih_key.k_objectid,
				INODE_PKEY (dir)->k_dir_id, 
				INODE_PKEY (dir)->k_objectid );
    } else {
	make_le_item_head (ih, 0, KEY_FORMAT_3_5, DOT_OFFSET, TYPE_DIRENTRY, EMPTY_DIR_SIZE, 2);
	
	make_empty_dir_item (body, ih->ih_key.k_dir_id, ih->ih_key.k_objectid,
		   		INODE_PKEY (dir)->k_dir_id, 
		   		INODE_PKEY (dir)->k_objectid );
    }
    
    /* look for place in the tree for new item */
    retval = search_item (sb, &key, path);
    if (retval == IO_ERROR) {
	reiserfs_warning ("vs-13080: reiserfs_new_directory: "
			  "i/o failure occurred creating new directory\n");
	return -EIO;
    }
    if (retval == ITEM_FOUND) {
	pathrelse (path);
	reiserfs_warning ("vs-13070: reiserfs_new_directory: "
			  "object with this key exists (%k)", &(ih->ih_key));
	return -EEXIST;
    }

    /* insert item, that is empty directory item */
    return reiserfs_insert_item (th, path, &key, ih, body);
}


/* stat data of object has been inserted, this inserts the item
   containing the body of symlink */
static int reiserfs_new_symlink (struct reiserfs_transaction_handle *th, 
				 struct item_head * ih,
				 struct path * path, const char * symname, int item_len)
{
    struct super_block * sb = th->t_super;
    struct cpu_key key;
    int retval;

    _make_cpu_key (&key, KEY_FORMAT_3_5, 
		   le32_to_cpu (ih->ih_key.k_dir_id), 
		   le32_to_cpu (ih->ih_key.k_objectid),
		   1, TYPE_DIRECT, 3/*key length*/);

    make_le_item_head (ih, 0, KEY_FORMAT_3_5, 1, TYPE_DIRECT, item_len, 0/*free_space*/);

    /* look for place in the tree for new item */
    retval = search_item (sb, &key, path);
    if (retval == IO_ERROR) {
	reiserfs_warning ("vs-13080: reiserfs_new_symlinik: "
			  "i/o failure occurred creating new symlink\n");
	return -EIO;
    }
    if (retval == ITEM_FOUND) {
	pathrelse (path);
	reiserfs_warning ("vs-13080: reiserfs_new_symlink: "
			  "object with this key exists (%k)", &(ih->ih_key));
	return -EEXIST;
    }

    /* insert item, that is body of symlink */
    return reiserfs_insert_item (th, path, &key, ih, symname);
}


/* inserts the stat data into the tree, and then calls
   reiserfs_new_directory (to insert ".", ".." item if new object is
   directory) or reiserfs_new_symlink (to insert symlink body if new
   object is symlink) or nothing (if new object is regular file) */
struct inode * reiserfs_new_inode (struct reiserfs_transaction_handle *th,
				   const struct inode * dir, int mode, 
				   const char * symname, 
				   int i_size, /* 0 for regular, EMTRY_DIR_SIZE for dirs,
						  strlen (symname) for symlinks)*/
				   struct dentry *dentry, struct inode *inode, int * err)
{
    struct super_block * sb;
    INITIALIZE_PATH (path_to_key);
    struct cpu_key key;
    struct item_head ih;
    struct stat_data sd;
    int retval;
  
    if (!dir || !dir->i_nlink) {
	*err = -EPERM;
	iput(inode) ;
	return NULL;
    }

    sb = dir->i_sb;
    inode->i_flags = 0;//inode->i_sb->s_flags;

    /* item head of new item */
    ih.ih_key.k_dir_id = INODE_PKEY (dir)->k_objectid;
    ih.ih_key.k_objectid = cpu_to_le32 (reiserfs_get_unused_objectid (th));
    if (!ih.ih_key.k_objectid) {
	iput(inode) ;
	*err = -ENOMEM;
	return NULL;
    }
    if (old_format_only (sb))
      /* not a perfect generation count, as object ids can be reused, but this
      ** is as good as reiserfs can do right now.
      ** note that the private part of inode isn't filled in yet, we have
      ** to use the directory.
      */
      inode->i_generation = le32_to_cpu (INODE_PKEY (dir)->k_objectid);
    else
#if defined( USE_INODE_GENERATION_COUNTER )
      inode->i_generation = 
	le32_to_cpu( sb -> u.reiserfs_sb.s_rs -> s_inode_generation );
#else
      inode->i_generation = ++event;
#endif
    if (old_format_only (sb))
	make_le_item_head (&ih, 0, KEY_FORMAT_3_5, SD_OFFSET, TYPE_STAT_DATA, SD_V1_SIZE, MAX_US_INT);
    else
	make_le_item_head (&ih, 0, KEY_FORMAT_3_6, SD_OFFSET, TYPE_STAT_DATA, SD_SIZE, MAX_US_INT);


    /* key to search for correct place for new stat data */
    _make_cpu_key (&key, KEY_FORMAT_3_6, le32_to_cpu (ih.ih_key.k_dir_id),
		   le32_to_cpu (ih.ih_key.k_objectid), SD_OFFSET, TYPE_STAT_DATA, 3/*key length*/);

    /* find proper place for inserting of stat data */
    retval = search_item (sb, &key, &path_to_key);
    if (retval == IO_ERROR) {
	iput (inode);
	*err = -EIO;
	return NULL;
    }
    if (retval == ITEM_FOUND) {
	pathrelse (&path_to_key);
	iput (inode);
	*err = -EEXIST;
	return NULL;
    }

    /* fill stat data */
    inode->i_mode = mode;
    inode->i_nlink = (S_ISDIR (mode) ? 2 : 1);
    inode->i_uid = current->fsuid;
    if (dir->i_mode & S_ISGID) {
	inode->i_gid = dir->i_gid;
	if (S_ISDIR(mode))
	    inode->i_mode |= S_ISGID;
    } else
	inode->i_gid = current->fsgid;

    inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
    inode->i_size = i_size;
    inode->i_blocks = (inode->i_size + 511) >> 9;
    inode->u.reiserfs_i.i_first_direct_byte = S_ISLNK(mode) ? 1 : 
      U32_MAX/*NO_BYTES_IN_DIRECT_ITEM*/;

    INIT_LIST_HEAD(&inode->u.reiserfs_i.i_prealloc_list) ;

    if (old_format_only (sb)) {
	if (inode->i_uid & ~0xffff || inode->i_gid & ~0xffff) {
	    pathrelse (&path_to_key);
	    /* i_uid or i_gid is too big to be stored in stat data v3.5 */
	    iput (inode);
	    *err = -EINVAL;
	    return NULL;
	}
	inode2sd_v1 (&sd, inode);
    } else
	inode2sd (&sd, inode);

    // these do not go to on-disk stat data
    inode->i_ino = le32_to_cpu (ih.ih_key.k_objectid);
    inode->i_blksize = PAGE_SIZE;
    inode->i_dev = sb->s_dev;
  
    // store in in-core inode the key of stat data and version all
    // object items will have (directory items will have old offset
    // format, other new objects will consist of new items)
    memcpy (INODE_PKEY (inode), &(ih.ih_key), KEY_SIZE);
    if (old_format_only (sb) || S_ISDIR(mode) || S_ISLNK(mode))
        set_inode_item_key_version (inode, KEY_FORMAT_3_5);
    else
        set_inode_item_key_version (inode, KEY_FORMAT_3_6);
    if (old_format_only (sb))
	set_inode_sd_version (inode, STAT_DATA_V1);
    else
	set_inode_sd_version (inode, STAT_DATA_V2);
    
    /* insert the stat data into the tree */
    retval = reiserfs_insert_item (th, &path_to_key, &key, &ih, (char *)(&sd));
    if (retval) {
	iput (inode);
	*err = retval;
	reiserfs_check_path(&path_to_key) ;
	return NULL;
    }

    if (S_ISDIR(mode)) {
	/* insert item with "." and ".." */
	retval = reiserfs_new_directory (th, &ih, &path_to_key, dir);
    }

    if (S_ISLNK(mode)) {
	/* insert body of symlink */
	if (!old_format_only (sb))
	    i_size = ROUND_UP(i_size);
	retval = reiserfs_new_symlink (th, &ih, &path_to_key, symname, i_size);
    }
    if (retval) {
      inode->i_nlink = 0;
	iput (inode);
	*err = retval;
	reiserfs_check_path(&path_to_key) ;
	return NULL;
    }

    insert_inode_hash (inode);
    // we do not mark inode dirty: on disk content matches to the
    // in-core one
    reiserfs_check_path(&path_to_key) ;

    return inode;
}

/*
** finds the tail page in the page cache,
** reads the last block in.
**