コード例 #1
0
/* add new name into a directory. If it exists in a directory - do
   nothing */
int reiserfs_add_entry (reiserfs_filsys_t fs, struct key * dir, char * name,
			 struct key * key, int fsck_need)
{
    struct item_head entry_ih = {{0,}, };
    char * entry;
    int retval;
    INITIALIZE_PATH(path);
    int gen_counter;
    int item_len;
    __u32 hash;

    if (reiserfs_find_entry (fs, dir, name, &gen_counter))
	return 0;

    /* compose entry key to look for its place in the tree */
    entry_ih.ih_key.k_dir_id = cpu_to_le32 (dir->k_dir_id);
    entry_ih.ih_key.k_objectid = cpu_to_le32 (dir->k_objectid);
    hash = hash_value (fs, name) + gen_counter;
    if (!strcmp (name, "."))
	hash = DOT_OFFSET;
    if (!strcmp (name, ".."))
	hash = DOT_DOT_OFFSET;
    set_type_and_offset (KEY_FORMAT_1, &(entry_ih.ih_key),
			 hash, TYPE_DIRENTRY);
    set_ih_key_format (&entry_ih, KEY_FORMAT_1);
    set_entry_count (&entry_ih, 1);
    if (SB_VERSION (fs) == REISERFS_VERSION_2)
	item_len = DEH_SIZE + ROUND_UP (strlen (name));
    else
	item_len = DEH_SIZE + strlen (name);
    set_ih_item_len (&entry_ih, item_len);

    /* fsck may need to insert item which was not reached yet */
    set_ih_fsck_need( &entry_ih, fsck_need );

    entry = make_entry (0, name, key, get_offset (&(entry_ih.ih_key)));

    retval = _search_by_entry_key (fs, &(entry_ih.ih_key), &path);
    switch (retval) {
    case POSITION_NOT_FOUND:
	reiserfs_paste_into_item (fs, &path, entry, item_len);
	break;

    case DIRECTORY_NOT_FOUND:
        set_deh_location( (struct reiserfs_de_head *)entry, DEH_SIZE );
	reiserfs_insert_item (fs, &path, &entry_ih, entry);
	break;

    default:
	reiserfs_panic ("reiserfs_add_entry: looking for %k (inserting name \"%s\") "
			"search_by_entry_key returned %d",
			&(entry_ih.ih_key), name, retval);
    }

    freemem (entry);
    return item_len;
}
/* this first locks inode (neither reads nor sync are permitted),
   reads tail through page cache, insert direct item. When direct item
   inserted successfully inode is left locked. Return value is always
   what we expect from it (number of cut bytes). But when tail remains
   in the unformatted node, we set mode to SKIP_BALANCING and unlock
   inode */
int indirect2direct (struct reiserfs_transaction_handle *th, 
		     struct inode * p_s_inode,
		     struct page *page, 
		     struct path * p_s_path, /* path to the indirect item. */
		     const struct cpu_key * p_s_item_key, /* Key to look for unformatted node pointer to be cut. */
		     loff_t n_new_file_size, /* New file size. */
		     char * p_c_mode)
{
    struct super_block * p_s_sb = p_s_inode->i_sb;
    struct item_head      s_ih;
    unsigned long n_block_size = p_s_sb->s_blocksize;
    char * tail;
    int tail_len, round_tail_len;
    loff_t pos, pos1; /* position of first byte of the tail */
    struct cpu_key key;

    p_s_sb->u.reiserfs_sb.s_indirect2direct ++;

    *p_c_mode = M_SKIP_BALANCING;

    /* store item head path points to. */
    copy_item_head (&s_ih, PATH_PITEM_HEAD(p_s_path));

    tail_len = (n_new_file_size & (n_block_size - 1));
    if (get_inode_sd_version (p_s_inode) == STAT_DATA_V2)
	round_tail_len = ROUND_UP (tail_len);
    else
	round_tail_len = tail_len;

    pos = le_ih_k_offset (&s_ih) - 1 + (ih_item_len(&s_ih) / UNFM_P_SIZE - 1) * p_s_sb->s_blocksize;
    pos1 = pos;

    // we are protected by i_sem. The tail can not disapper, not
    // append can be done either
    // we are in truncate or packing tail in file_release

    tail = (char *)kmap(page) ; /* this can schedule */

    if (path_changed (&s_ih, p_s_path)) {
	/* re-search indirect item */
	if ( search_for_position_by_key (p_s_sb, p_s_item_key, p_s_path) == POSITION_NOT_FOUND )
	    reiserfs_panic(p_s_sb, "PAP-5520: indirect2direct: "
			   "item to be converted %K does not exist", p_s_item_key);
	copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path));
#ifdef CONFIG_REISERFS_CHECK
	pos = le_ih_k_offset (&s_ih) - 1 + 
	    (ih_item_len(&s_ih) / UNFM_P_SIZE - 1) * p_s_sb->s_blocksize;
	if (pos != pos1)
	    reiserfs_panic (p_s_sb, "vs-5530: indirect2direct: "
			    "tail position changed while we were reading it");
#endif
    }


    /* Set direct item header to insert. */
    make_le_item_head (&s_ih, 0, get_inode_item_key_version (p_s_inode), pos1 + 1,
		       TYPE_DIRECT, round_tail_len, 0xffff/*ih_free_space*/);

    /* we want a pointer to the first byte of the tail in the page.
    ** the page was locked and this part of the page was up to date when
    ** indirect2direct was called, so we know the bytes are still valid
    */
    tail = tail + (pos & (PAGE_CACHE_SIZE - 1)) ;

    PATH_LAST_POSITION(p_s_path)++;

    key = *p_s_item_key;
    set_cpu_key_k_type (&key, TYPE_DIRECT);
    key.key_length = 4;
    /* Insert tail as new direct item in the tree */
    if ( reiserfs_insert_item(th, p_s_path, &key, &s_ih,
			      tail ? tail : NULL) < 0 ) {
	/* No disk memory. So we can not convert last unformatted node
	   to the direct item.  In this case we used to adjust
	   indirect items's ih_free_space. Now ih_free_space is not
	   used, it would be ideal to write zeros to corresponding
	   unformatted node. For now i_size is considered as guard for
	   going out of file size */
	kunmap(page) ;
	return n_block_size - round_tail_len;
    }
    kunmap(page) ;

    /* this will invalidate all the buffers in the page after
    ** pos1
    */
    unmap_buffers(page, pos1) ;

    // note: we have now the same as in above direct2indirect
    // conversion: there are two keys which have matching first three
    // key components. They only differ by the fouhth one.

    /* We have inserted new direct item and must remove last
       unformatted node. */
    p_s_inode->i_blocks += (p_s_sb->s_blocksize / 512);
    *p_c_mode = M_CUT;

    /* we store position of first direct item in the in-core inode */
    //mark_file_with_tail (p_s_inode, pos1 + 1);
    p_s_inode->u.reiserfs_i.i_first_direct_byte = pos1 + 1;

    return n_block_size - round_tail_len;
}
/* path points to first direct item of the file regarless of how many of
   them are there */
int direct2indirect (struct reiserfs_transaction_handle *th, struct inode * inode, 
		     struct path * path, struct buffer_head * unbh,
		     loff_t tail_offset)
{
    struct super_block * sb = inode->i_sb;
    struct buffer_head *up_to_date_bh ;
    struct item_head * p_le_ih = PATH_PITEM_HEAD (path);
    unsigned long total_tail = 0 ;
    struct cpu_key end_key;  /* Key to search for the last byte of the
				converted item. */
    struct item_head ind_ih; /* new indirect item to be inserted or
                                key of unfm pointer to be pasted */
    int	n_blk_size,
      n_retval;	  /* returned value for reiserfs_insert_item and clones */
    struct unfm_nodeinfo unfm_ptr;  /* Handle on an unformatted node
				       that will be inserted in the
				       tree. */


    sb->u.reiserfs_sb.s_direct2indirect ++;

    n_blk_size = sb->s_blocksize;

    /* and key to search for append or insert pointer to the new
       unformatted node. */
    copy_item_head (&ind_ih, p_le_ih);
    set_le_ih_k_offset (&ind_ih, tail_offset);
    set_le_ih_k_type (&ind_ih, TYPE_INDIRECT);

    /* Set the key to search for the place for new unfm pointer */
    make_cpu_key (&end_key, inode, tail_offset, TYPE_INDIRECT, 4);

    // FIXME: we could avoid this 
    if ( search_for_position_by_key (sb, &end_key, path) == POSITION_FOUND ) {
	reiserfs_warning ("PAP-14030: direct2indirect: "
			"pasted or inserted byte exists in the tree %K. "
			"Use fsck to repair.\n", &end_key);
	pathrelse(path);
	return -EIO;
    }
    
    p_le_ih = PATH_PITEM_HEAD (path);

    unfm_ptr.unfm_nodenum = cpu_to_le32 (unbh->b_blocknr);
    unfm_ptr.unfm_freespace = 0; // ???
    
    if ( is_statdata_le_ih (p_le_ih) )  {
	/* Insert new indirect item. */
	set_ih_free_space (&ind_ih, 0); /* delete at nearest future */
        put_ih_item_len( &ind_ih, UNFM_P_SIZE );
	PATH_LAST_POSITION (path)++;
	n_retval = reiserfs_insert_item (th, path, &end_key, &ind_ih, 
					 (char *)&unfm_ptr);
    } else {
	/* Paste into last indirect item of an object. */
	n_retval = reiserfs_paste_into_item(th, path, &end_key,
					    (char *)&unfm_ptr, UNFM_P_SIZE);
    }
    if ( n_retval ) {
	return n_retval;
    }

    // note: from here there are two keys which have matching first
    // three key components. They only differ by the fourth one.


    /* Set the key to search for the direct items of the file */
    make_cpu_key (&end_key, inode, max_reiserfs_offset (inode), TYPE_DIRECT, 4);

    /* Move bytes from the direct items to the new unformatted node
       and delete them. */
    while (1)  {
	int tail_size;

	/* end_key.k_offset is set so, that we will always have found
           last item of the file */
	if ( search_for_position_by_key (sb, &end_key, path) == POSITION_FOUND )
	    reiserfs_panic (sb, "PAP-14050: direct2indirect: "
			    "direct item (%K) not found", &end_key);
	p_le_ih = PATH_PITEM_HEAD (path);
	RFALSE( !is_direct_le_ih (p_le_ih),
	        "vs-14055: direct item expected(%K), found %h",
                &end_key, p_le_ih);
        tail_size = (le_ih_k_offset (p_le_ih) & (n_blk_size - 1))
            + ih_item_len(p_le_ih) - 1;

	/* we only send the unbh pointer if the buffer is not up to date.
	** this avoids overwriting good data from writepage() with old data
	** from the disk or buffer cache
	** Special case: unbh->b_page will be NULL if we are coming through
	** DIRECT_IO handler here.
	*/
	if ( !unbh->b_page || buffer_uptodate(unbh) || Page_Uptodate(unbh->b_page)) {
	    up_to_date_bh = NULL ;
	} else {
	    up_to_date_bh = unbh ;
	}
	n_retval = reiserfs_delete_item (th, path, &end_key, inode, 
	                                 up_to_date_bh) ;

	total_tail += n_retval ;
	if (tail_size == n_retval)
	    // done: file does not have direct items anymore
	    break;

    }
    /* if we've copied bytes from disk into the page, we need to zero
    ** out the unused part of the block (it was not up to date before)
    ** the page is still kmapped (by whoever called reiserfs_get_block)
    */
    if (up_to_date_bh) {
        unsigned pgoff = (tail_offset + total_tail - 1) & (PAGE_CACHE_SIZE - 1);
	memset(page_address(unbh->b_page) + pgoff, 0, n_blk_size - total_tail) ;
    }

    inode->u.reiserfs_i.i_first_direct_byte = U32_MAX;

    reiserfs_update_tail_transaction(inode);
    return 0;
}
コード例 #4
0
ファイル: super.c プロジェクト: niubl/camera_project
/* to protect file being unlinked from getting lost we "safe" link files
   being unlinked. This link will be deleted in the same transaction with last
   item of file. mounting the filesytem we scan all these links and remove
   files which almost got lost */
void add_save_link (struct reiserfs_transaction_handle * th,
		    struct inode * inode, int truncate)
{
    INITIALIZE_PATH (path);
    int retval;
    struct cpu_key key;
    struct item_head ih;
    __u32 link;

    /* file can only get one "save link" of each kind */
    RFALSE( truncate && 
	    ( inode -> u.reiserfs_i.i_flags & i_link_saved_truncate_mask ),
	    "saved link already exists for truncated inode %lx",
	    ( long ) inode -> i_ino );
    RFALSE( !truncate && 
	    ( inode -> u.reiserfs_i.i_flags & i_link_saved_unlink_mask ),
	    "saved link already exists for unlinked inode %lx",
	    ( long ) inode -> i_ino );

    /* setup key of "save" link */
    key.version = KEY_FORMAT_3_5;
    key.on_disk_key.k_dir_id = MAX_KEY_OBJECTID;
    key.on_disk_key.k_objectid = inode->i_ino;
    if (!truncate) {
	/* unlink, rmdir, rename */
	set_cpu_key_k_offset (&key, 1 + inode->i_sb->s_blocksize);
	set_cpu_key_k_type (&key, TYPE_DIRECT);

	/* item head of "safe" link */
	make_le_item_head (&ih, &key, key.version, 1 + inode->i_sb->s_blocksize, TYPE_DIRECT,
			   4/*length*/, 0xffff/*free space*/);
    } else {
	/* truncate */
	if (S_ISDIR (inode->i_mode))
	    reiserfs_warning("green-2102: Adding a truncate savelink for a directory %k! Please report\n", INODE_PKEY(inode));
	set_cpu_key_k_offset (&key, 1);
	set_cpu_key_k_type (&key, TYPE_INDIRECT);

	/* item head of "safe" link */
	make_le_item_head (&ih, &key, key.version, 1, TYPE_INDIRECT,
			   4/*length*/, 0/*free space*/);
    }
    key.key_length = 3;

    /* look for its place in the tree */
    retval = search_item (inode->i_sb, &key, &path);
    if (retval != ITEM_NOT_FOUND) {
	if ( retval != -ENOSPC )
	    reiserfs_warning ("vs-2100: add_save_link:"
			  "search_by_key (%K) returned %d\n", &key, retval);
	pathrelse (&path);
	return;
    }

    /* body of "save" link */
    link = cpu_to_le32 (INODE_PKEY (inode)->k_dir_id);

    /* put "save" link inot tree */
    retval = reiserfs_insert_item (th, &path, &key, &ih, (char *)&link);
    if (retval) {
	if (retval != -ENOSPC)
	    reiserfs_warning ("vs-2120: add_save_link: insert_item returned %d\n",
			  retval);
    } else {
	if( truncate )
	    inode -> u.reiserfs_i.i_flags |= i_link_saved_truncate_mask;
	else
	    inode -> u.reiserfs_i.i_flags |= i_link_saved_unlink_mask;
    }
}
コード例 #5
0
int indirect2direct(struct reiserfs_transaction_handle *th,
		    struct inode *inode, struct page *page,
		    struct treepath *path,	
		    const struct cpu_key *item_key,	
		    loff_t n_new_file_size,	
		    char *mode)
{
	struct super_block *sb = inode->i_sb;
	struct item_head s_ih;
	unsigned long block_size = sb->s_blocksize;
	char *tail;
	int tail_len, round_tail_len;
	loff_t pos, pos1;	
	struct cpu_key key;

	BUG_ON(!th->t_trans_id);

	REISERFS_SB(sb)->s_indirect2direct++;

	*mode = M_SKIP_BALANCING;

	
	copy_item_head(&s_ih, PATH_PITEM_HEAD(path));

	tail_len = (n_new_file_size & (block_size - 1));
	if (get_inode_sd_version(inode) == STAT_DATA_V2)
		round_tail_len = ROUND_UP(tail_len);
	else
		round_tail_len = tail_len;

	pos =
	    le_ih_k_offset(&s_ih) - 1 + (ih_item_len(&s_ih) / UNFM_P_SIZE -
					 1) * sb->s_blocksize;
	pos1 = pos;

	
	
	

	tail = (char *)kmap(page);	

	if (path_changed(&s_ih, path)) {
		
		if (search_for_position_by_key(sb, item_key, path)
		    == POSITION_NOT_FOUND)
			reiserfs_panic(sb, "PAP-5520",
				       "item to be converted %K does not exist",
				       item_key);
		copy_item_head(&s_ih, PATH_PITEM_HEAD(path));
#ifdef CONFIG_REISERFS_CHECK
		pos = le_ih_k_offset(&s_ih) - 1 +
		    (ih_item_len(&s_ih) / UNFM_P_SIZE -
		     1) * sb->s_blocksize;
		if (pos != pos1)
			reiserfs_panic(sb, "vs-5530", "tail position "
				       "changed while we were reading it");
#endif
	}

	
	make_le_item_head(&s_ih, NULL, get_inode_item_key_version(inode),
			  pos1 + 1, TYPE_DIRECT, round_tail_len,
			  0xffff  );

	tail = tail + (pos & (PAGE_CACHE_SIZE - 1));

	PATH_LAST_POSITION(path)++;

	key = *item_key;
	set_cpu_key_k_type(&key, TYPE_DIRECT);
	key.key_length = 4;
	
	if (reiserfs_insert_item(th, path, &key, &s_ih, inode,
				 tail ? tail : NULL) < 0) {
		kunmap(page);
		return block_size - round_tail_len;
	}
	kunmap(page);

	
	reiserfs_update_sd(th, inode);

	
	
	

	*mode = M_CUT;

	
	
	REISERFS_I(inode)->i_first_direct_byte = pos1 + 1;

	return block_size - round_tail_len;
}
コード例 #6
0
int direct2indirect(struct reiserfs_transaction_handle *th, struct inode *inode,
		    struct treepath *path, struct buffer_head *unbh,
		    loff_t tail_offset)
{
	struct super_block *sb = inode->i_sb;
	struct buffer_head *up_to_date_bh;
	struct item_head *p_le_ih = PATH_PITEM_HEAD(path);
	unsigned long total_tail = 0;
	struct cpu_key end_key;	
	struct item_head ind_ih;	
	int blk_size, retval;	
	unp_t unfm_ptr;		

	BUG_ON(!th->t_trans_id);

	REISERFS_SB(sb)->s_direct2indirect++;

	blk_size = sb->s_blocksize;

	copy_item_head(&ind_ih, p_le_ih);
	set_le_ih_k_offset(&ind_ih, tail_offset);
	set_le_ih_k_type(&ind_ih, TYPE_INDIRECT);

	
	make_cpu_key(&end_key, inode, tail_offset, TYPE_INDIRECT, 4);

	
	if (search_for_position_by_key(sb, &end_key, path) == POSITION_FOUND) {
		reiserfs_error(sb, "PAP-14030",
			       "pasted or inserted byte exists in "
			       "the tree %K. Use fsck to repair.", &end_key);
		pathrelse(path);
		return -EIO;
	}

	p_le_ih = PATH_PITEM_HEAD(path);

	unfm_ptr = cpu_to_le32(unbh->b_blocknr);

	if (is_statdata_le_ih(p_le_ih)) {
		
		set_ih_free_space(&ind_ih, 0);	
		put_ih_item_len(&ind_ih, UNFM_P_SIZE);
		PATH_LAST_POSITION(path)++;
		retval =
		    reiserfs_insert_item(th, path, &end_key, &ind_ih, inode,
					 (char *)&unfm_ptr);
	} else {
		
		retval = reiserfs_paste_into_item(th, path, &end_key, inode,
						    (char *)&unfm_ptr,
						    UNFM_P_SIZE);
	}
	if (retval) {
		return retval;
	}
	
	

	
	make_cpu_key(&end_key, inode, max_reiserfs_offset(inode), TYPE_DIRECT,
		     4);

	while (1) {
		int tail_size;

		if (search_for_position_by_key(sb, &end_key, path) ==
		    POSITION_FOUND)
			reiserfs_panic(sb, "PAP-14050",
				       "direct item (%K) not found", &end_key);
		p_le_ih = PATH_PITEM_HEAD(path);
		RFALSE(!is_direct_le_ih(p_le_ih),
		       "vs-14055: direct item expected(%K), found %h",
		       &end_key, p_le_ih);
		tail_size = (le_ih_k_offset(p_le_ih) & (blk_size - 1))
		    + ih_item_len(p_le_ih) - 1;

		if (!unbh->b_page || buffer_uptodate(unbh)
		    || PageUptodate(unbh->b_page)) {
			up_to_date_bh = NULL;
		} else {
			up_to_date_bh = unbh;
		}
		retval = reiserfs_delete_item(th, path, &end_key, inode,
						up_to_date_bh);

		total_tail += retval;
		if (tail_size == retval)
			
			break;

	}
	if (up_to_date_bh) {
		unsigned pgoff =
		    (tail_offset + total_tail - 1) & (PAGE_CACHE_SIZE - 1);
		char *kaddr = kmap_atomic(up_to_date_bh->b_page);
		memset(kaddr + pgoff, 0, blk_size - total_tail);
		kunmap_atomic(kaddr);
	}

	REISERFS_I(inode)->i_first_direct_byte = U32_MAX;

	return 0;
}
コード例 #7
0
ファイル: tail_conversion.c プロジェクト: 020gzh/linux
/*
 * path points to first direct item of the file regardless of how many of
 * them are there
 */
int direct2indirect(struct reiserfs_transaction_handle *th, struct inode *inode,
		    struct treepath *path, struct buffer_head *unbh,
		    loff_t tail_offset)
{
	struct super_block *sb = inode->i_sb;
	struct buffer_head *up_to_date_bh;
	struct item_head *p_le_ih = tp_item_head(path);
	unsigned long total_tail = 0;

	/* Key to search for the last byte of the converted item. */
	struct cpu_key end_key;

	/*
	 * new indirect item to be inserted or key
	 * of unfm pointer to be pasted
	 */
	struct item_head ind_ih;
	int blk_size;
	/* returned value for reiserfs_insert_item and clones */
	int  retval;
	/* Handle on an unformatted node that will be inserted in the tree. */
	unp_t unfm_ptr;

	BUG_ON(!th->t_trans_id);

	REISERFS_SB(sb)->s_direct2indirect++;

	blk_size = sb->s_blocksize;

	/*
	 * and key to search for append or insert pointer to the new
	 * unformatted node.
	 */
	copy_item_head(&ind_ih, p_le_ih);
	set_le_ih_k_offset(&ind_ih, tail_offset);
	set_le_ih_k_type(&ind_ih, TYPE_INDIRECT);

	/* Set the key to search for the place for new unfm pointer */
	make_cpu_key(&end_key, inode, tail_offset, TYPE_INDIRECT, 4);

	/* FIXME: we could avoid this */
	if (search_for_position_by_key(sb, &end_key, path) == POSITION_FOUND) {
		reiserfs_error(sb, "PAP-14030",
			       "pasted or inserted byte exists in "
			       "the tree %K. Use fsck to repair.", &end_key);
		pathrelse(path);
		return -EIO;
	}

	p_le_ih = tp_item_head(path);

	unfm_ptr = cpu_to_le32(unbh->b_blocknr);

	if (is_statdata_le_ih(p_le_ih)) {
		/* Insert new indirect item. */
		set_ih_free_space(&ind_ih, 0);	/* delete at nearest future */
		put_ih_item_len(&ind_ih, UNFM_P_SIZE);
		PATH_LAST_POSITION(path)++;
		retval =
		    reiserfs_insert_item(th, path, &end_key, &ind_ih, inode,
					 (char *)&unfm_ptr);
	} else {
		/* Paste into last indirect item of an object. */
		retval = reiserfs_paste_into_item(th, path, &end_key, inode,
						    (char *)&unfm_ptr,
						    UNFM_P_SIZE);
	}
	if (retval) {
		return retval;
	}
	/*
	 * note: from here there are two keys which have matching first
	 *  three key components. They only differ by the fourth one.
	 */

	/* Set the key to search for the direct items of the file */
	make_cpu_key(&end_key, inode, max_reiserfs_offset(inode), TYPE_DIRECT,
		     4);

	/*
	 * Move bytes from the direct items to the new unformatted node
	 * and delete them.
	 */
	while (1) {
		int tail_size;

		/*
		 * end_key.k_offset is set so, that we will always have found
		 * last item of the file
		 */
		if (search_for_position_by_key(sb, &end_key, path) ==
		    POSITION_FOUND)
			reiserfs_panic(sb, "PAP-14050",
				       "direct item (%K) not found", &end_key);
		p_le_ih = tp_item_head(path);
		RFALSE(!is_direct_le_ih(p_le_ih),
		       "vs-14055: direct item expected(%K), found %h",
		       &end_key, p_le_ih);
		tail_size = (le_ih_k_offset(p_le_ih) & (blk_size - 1))
		    + ih_item_len(p_le_ih) - 1;

		/*
		 * we only send the unbh pointer if the buffer is not
		 * up to date.  this avoids overwriting good data from
		 * writepage() with old data from the disk or buffer cache
		 * Special case: unbh->b_page will be NULL if we are coming
		 * through DIRECT_IO handler here.
		 */
		if (!unbh->b_page || buffer_uptodate(unbh)
		    || PageUptodate(unbh->b_page)) {
			up_to_date_bh = NULL;
		} else {
			up_to_date_bh = unbh;
		}
		retval = reiserfs_delete_item(th, path, &end_key, inode,
						up_to_date_bh);

		total_tail += retval;

		/* done: file does not have direct items anymore */
		if (tail_size == retval)
			break;

	}
	/*
	 * if we've copied bytes from disk into the page, we need to zero
	 * out the unused part of the block (it was not up to date before)
	 */
	if (up_to_date_bh) {
		unsigned pgoff =
		    (tail_offset + total_tail - 1) & (PAGE_SIZE - 1);
		char *kaddr = kmap_atomic(up_to_date_bh->b_page);
		memset(kaddr + pgoff, 0, blk_size - total_tail);
		kunmap_atomic(kaddr);
	}

	REISERFS_I(inode)->i_first_direct_byte = U32_MAX;

	return 0;
}
コード例 #8
0
ファイル: tail_conversion.c プロジェクト: 020gzh/linux
/*
 * this first locks inode (neither reads nor sync are permitted),
 * reads tail through page cache, insert direct item. When direct item
 * inserted successfully inode is left locked. Return value is always
 * what we expect from it (number of cut bytes). But when tail remains
 * in the unformatted node, we set mode to SKIP_BALANCING and unlock
 * inode
 */
int indirect2direct(struct reiserfs_transaction_handle *th,
		    struct inode *inode, struct page *page,
		    struct treepath *path,	/* path to the indirect item. */
		    const struct cpu_key *item_key,	/* Key to look for
							 * unformatted node
							 * pointer to be cut. */
		    loff_t n_new_file_size,	/* New file size. */
		    char *mode)
{
	struct super_block *sb = inode->i_sb;
	struct item_head s_ih;
	unsigned long block_size = sb->s_blocksize;
	char *tail;
	int tail_len, round_tail_len;
	loff_t pos, pos1;	/* position of first byte of the tail */
	struct cpu_key key;

	BUG_ON(!th->t_trans_id);

	REISERFS_SB(sb)->s_indirect2direct++;

	*mode = M_SKIP_BALANCING;

	/* store item head path points to. */
	copy_item_head(&s_ih, tp_item_head(path));

	tail_len = (n_new_file_size & (block_size - 1));
	if (get_inode_sd_version(inode) == STAT_DATA_V2)
		round_tail_len = ROUND_UP(tail_len);
	else
		round_tail_len = tail_len;

	pos =
	    le_ih_k_offset(&s_ih) - 1 + (ih_item_len(&s_ih) / UNFM_P_SIZE -
					 1) * sb->s_blocksize;
	pos1 = pos;

	/*
	 * we are protected by i_mutex. The tail can not disapper, not
	 * append can be done either
	 * we are in truncate or packing tail in file_release
	 */

	tail = (char *)kmap(page);	/* this can schedule */

	if (path_changed(&s_ih, path)) {
		/* re-search indirect item */
		if (search_for_position_by_key(sb, item_key, path)
		    == POSITION_NOT_FOUND)
			reiserfs_panic(sb, "PAP-5520",
				       "item to be converted %K does not exist",
				       item_key);
		copy_item_head(&s_ih, tp_item_head(path));
#ifdef CONFIG_REISERFS_CHECK
		pos = le_ih_k_offset(&s_ih) - 1 +
		    (ih_item_len(&s_ih) / UNFM_P_SIZE -
		     1) * sb->s_blocksize;
		if (pos != pos1)
			reiserfs_panic(sb, "vs-5530", "tail position "
				       "changed while we were reading it");
#endif
	}

	/* Set direct item header to insert. */
	make_le_item_head(&s_ih, NULL, get_inode_item_key_version(inode),
			  pos1 + 1, TYPE_DIRECT, round_tail_len,
			  0xffff /*ih_free_space */ );

	/*
	 * we want a pointer to the first byte of the tail in the page.
	 * the page was locked and this part of the page was up to date when
	 * indirect2direct was called, so we know the bytes are still valid
	 */
	tail = tail + (pos & (PAGE_SIZE - 1));

	PATH_LAST_POSITION(path)++;

	key = *item_key;
	set_cpu_key_k_type(&key, TYPE_DIRECT);
	key.key_length = 4;
	/* Insert tail as new direct item in the tree */
	if (reiserfs_insert_item(th, path, &key, &s_ih, inode,
				 tail ? tail : NULL) < 0) {
		/*
		 * No disk memory. So we can not convert last unformatted node
		 * to the direct item.  In this case we used to adjust
		 * indirect items's ih_free_space. Now ih_free_space is not
		 * used, it would be ideal to write zeros to corresponding
		 * unformatted node. For now i_size is considered as guard for
		 * going out of file size
		 */
		kunmap(page);
		return block_size - round_tail_len;
	}
	kunmap(page);

	/* make sure to get the i_blocks changes from reiserfs_insert_item */
	reiserfs_update_sd(th, inode);

	/*
	 * note: we have now the same as in above direct2indirect
	 * conversion: there are two keys which have matching first three
	 * key components. They only differ by the fourth one.
	 */

	/*
	 * We have inserted new direct item and must remove last
	 * unformatted node.
	 */
	*mode = M_CUT;

	/* we store position of first direct item in the in-core inode */
	/* mark_file_with_tail (inode, pos1 + 1); */
	REISERFS_I(inode)->i_first_direct_byte = pos1 + 1;

	return block_size - round_tail_len;
}