示例#1
0
int reiserfs_readdir_dentry(struct dentry *dentry, void *dirent,
			   filldir_t filldir, loff_t *pos)
{
	struct inode *inode = dentry->d_inode;
	struct cpu_key pos_key;	
	INITIALIZE_PATH(path_to_entry);
	struct buffer_head *bh;
	int item_num, entry_num;
	const struct reiserfs_key *rkey;
	struct item_head *ih, tmp_ih;
	int search_res;
	char *local_buf;
	loff_t next_pos;
	char small_buf[32];	
	struct reiserfs_dir_entry de;
	int ret = 0;

	reiserfs_write_lock(inode->i_sb);

	reiserfs_check_lock_depth(inode->i_sb, "readdir");

	make_cpu_key(&pos_key, inode, *pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
	next_pos = cpu_key_k_offset(&pos_key);

	path_to_entry.reada = PATH_READA;
	while (1) {
	      research:
		
		search_res =
		    search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
					&de);
		if (search_res == IO_ERROR) {
			
			
			ret = -EIO;
			goto out;
		}
		entry_num = de.de_entry_num;
		bh = de.de_bh;
		item_num = de.de_item_num;
		ih = de.de_ih;
		store_ih(&tmp_ih, ih);

		
		RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
		       "vs-9000: found item %h does not match to dir we readdir %K",
		       ih, &pos_key);
		RFALSE(item_num > B_NR_ITEMS(bh) - 1,
		       "vs-9005 item_num == %d, item amount == %d",
		       item_num, B_NR_ITEMS(bh));

		
		RFALSE(I_ENTRY_COUNT(ih) < entry_num,
		       "vs-9010: entry number is too big %d (%d)",
		       entry_num, I_ENTRY_COUNT(ih));

		if (search_res == POSITION_FOUND
		    || entry_num < I_ENTRY_COUNT(ih)) {
			
			struct reiserfs_de_head *deh =
			    B_I_DEH(bh, ih) + entry_num;

			for (; entry_num < I_ENTRY_COUNT(ih);
			     entry_num++, deh++) {
				int d_reclen;
				char *d_name;
				off_t d_off;
				ino_t d_ino;

				if (!de_visible(deh))
					
					continue;
				d_reclen = entry_length(bh, ih, entry_num);
				d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);

				if (d_reclen <= 0 ||
				    d_name + d_reclen > bh->b_data + bh->b_size) {
					pathrelse(&path_to_entry);
					ret = -EIO;
					goto out;
				}

				if (!d_name[d_reclen - 1])
					d_reclen = strlen(d_name);

				if (d_reclen >
				    REISERFS_MAX_NAME(inode->i_sb->
						      s_blocksize)) {
					
					continue;
				}

				
				if (is_privroot_deh(dentry, deh))
					continue;

				d_off = deh_offset(deh);
				*pos = d_off;
				d_ino = deh_objectid(deh);
				if (d_reclen <= 32) {
					local_buf = small_buf;
				} else {
					local_buf = kmalloc(d_reclen,
							    GFP_NOFS);
					if (!local_buf) {
						pathrelse(&path_to_entry);
						ret = -ENOMEM;
						goto out;
					}
					if (item_moved(&tmp_ih, &path_to_entry)) {
						kfree(local_buf);
						goto research;
					}
				}
				
				
				
				
				memcpy(local_buf, d_name, d_reclen);

				reiserfs_write_unlock(inode->i_sb);
				if (filldir
				    (dirent, local_buf, d_reclen, d_off, d_ino,
				     DT_UNKNOWN) < 0) {
					reiserfs_write_lock(inode->i_sb);
					if (local_buf != small_buf) {
						kfree(local_buf);
					}
					goto end;
				}
				reiserfs_write_lock(inode->i_sb);
				if (local_buf != small_buf) {
					kfree(local_buf);
				}
				
				next_pos = deh_offset(deh) + 1;

				if (item_moved(&tmp_ih, &path_to_entry)) {
					goto research;
				}
			}	
		}

		if (item_num != B_NR_ITEMS(bh) - 1)
			
			goto end;

		rkey = get_rkey(&path_to_entry, inode->i_sb);
		if (!comp_le_keys(rkey, &MIN_KEY)) {
			set_cpu_key_k_offset(&pos_key, next_pos);
			continue;
		}

		if (COMP_SHORT_KEYS(rkey, &pos_key)) {
			
			goto end;
		}

		
		set_cpu_key_k_offset(&pos_key,
				     le_key_k_offset(KEY_FORMAT_3_5, rkey));

	}			

end:
	*pos = next_pos;
	pathrelse(&path_to_entry);
	reiserfs_check_path(&path_to_entry);
out:
	reiserfs_write_unlock(inode->i_sb);
	return ret;
}
示例#2
0
static int reiserfs_readdir (struct file * filp, void * dirent, filldir_t filldir)
{
    struct inode *inode = filp->f_dentry->d_inode;
    struct cpu_key pos_key;	/* key of current position in the directory (key of directory entry) */
    INITIALIZE_PATH (path_to_entry);
    struct buffer_head * bh;
    int item_num, entry_num;
    const struct key * rkey;
    struct item_head * ih, tmp_ih;
    int search_res;
    char * local_buf;
    loff_t next_pos;
    char small_buf[32] ; /* avoid kmalloc if we can */
    struct reiserfs_dir_entry de;


    reiserfs_check_lock_depth("readdir") ;

    /* form key for search the next directory entry using f_pos field of
       file structure */
    make_cpu_key (&pos_key, inode, (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET,
		  TYPE_DIRENTRY, 3);
    next_pos = cpu_key_k_offset (&pos_key);

    /*  reiserfs_warning ("reiserfs_readdir 1: f_pos = %Ld\n", filp->f_pos);*/

    while (1) {
    research:
	/* search the directory item, containing entry with specified key */
	search_res = search_by_entry_key (inode->i_sb, &pos_key, &path_to_entry, &de);
	if (search_res == IO_ERROR) {
	    // FIXME: we could just skip part of directory which could
	    // not be read
	    return -EIO;
	}
	entry_num = de.de_entry_num;
	bh = de.de_bh;
	item_num = de.de_item_num;
	ih = de.de_ih;
	store_ih (&tmp_ih, ih);
		
	/* we must have found item, that is item of this directory, */
	RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key),
		"vs-9000: found item %h does not match to dir we readdir %K",
		ih, &pos_key);
	RFALSE( item_num > B_NR_ITEMS (bh) - 1,
		"vs-9005 item_num == %d, item amount == %d", 
		item_num, B_NR_ITEMS (bh));
      
	/* and entry must be not more than number of entries in the item */
	RFALSE( I_ENTRY_COUNT (ih) < entry_num,
		"vs-9010: entry number is too big %d (%d)", 
		entry_num, I_ENTRY_COUNT (ih));

	if (search_res == POSITION_FOUND || entry_num < I_ENTRY_COUNT (ih)) {
	    /* go through all entries in the directory item beginning from the entry, that has been found */
	    struct reiserfs_de_head * deh = B_I_DEH (bh, ih) + entry_num;

	    for (; entry_num < I_ENTRY_COUNT (ih); entry_num ++, deh ++) {
		int d_reclen;
		char * d_name;
		off_t d_off;
		ino_t d_ino;

		if (!de_visible (deh))
		    /* it is hidden entry */
		    continue;
		d_reclen = entry_length (bh, ih, entry_num);
		d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh);
		if (!d_name[d_reclen - 1])
		    d_reclen = strlen (d_name);
	
		if (d_reclen > REISERFS_MAX_NAME_LEN(inode->i_sb->s_blocksize)){
		    /* too big to send back to VFS */
		    continue ;
		}
		d_off = deh_offset (deh);
		filp->f_pos = d_off ;
		d_ino = deh_objectid (deh);
		if (d_reclen <= 32) {
		  local_buf = small_buf ;
		} else {
		    local_buf = reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb) ;
		    if (!local_buf) {
			pathrelse (&path_to_entry);
			return -ENOMEM ;
		    }
		    if (item_moved (&tmp_ih, &path_to_entry)) {
			reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
			goto research;
		    }
		}
		// Note, that we copy name to user space via temporary
		// buffer (local_buf) because filldir will block if
		// user space buffer is swapped out. At that time
		// entry can move to somewhere else
		memcpy (local_buf, d_name, d_reclen);
		if (filldir (dirent, local_buf, d_reclen, d_off, d_ino, 
		             DT_UNKNOWN) < 0) {
		    if (local_buf != small_buf) {
			reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
		    }
		    goto end;
		}
		if (local_buf != small_buf) {
		    reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
		}

		// next entry should be looked for with such offset
		next_pos = deh_offset (deh) + 1;

		if (item_moved (&tmp_ih, &path_to_entry)) {
		    goto research;
		}
	    } /* for */
	}

	if (item_num != B_NR_ITEMS (bh) - 1)
	    // end of directory has been reached
	    goto end;

	/* item we went through is last item of node. Using right
	   delimiting key check is it directory end */
	rkey = get_rkey (&path_to_entry, inode->i_sb);
	if (! comp_le_keys (rkey, &MIN_KEY)) {
	    /* set pos_key to key, that is the smallest and greater
	       that key of the last entry in the item */
	    set_cpu_key_k_offset (&pos_key, next_pos);
	    continue;
	}

	if ( COMP_SHORT_KEYS (rkey, &pos_key)) {
	    // end of directory has been reached
	    goto end;
	}
	
	/* directory continues in the right neighboring block */
	set_cpu_key_k_offset (&pos_key, le_key_k_offset (KEY_FORMAT_3_5, rkey));

    } /* while */


 end:
    // FIXME: ext2_readdir does not reset f_pos
    filp->f_pos = next_pos;
    pathrelse (&path_to_entry);
    reiserfs_check_path(&path_to_entry) ;
    UPDATE_ATIME(inode) ;
    return 0;
}
示例#3
0
int reiserfs_readdir_dentry(struct dentry *dentry, void *dirent,
			   filldir_t filldir, loff_t *pos)
{
	struct inode *inode = dentry->d_inode;
	struct cpu_key pos_key;	/* key of current position in the directory (key of directory entry) */
	INITIALIZE_PATH(path_to_entry);
	struct buffer_head *bh;
	int item_num, entry_num;
	const struct reiserfs_key *rkey;
	struct item_head *ih, tmp_ih;
	int search_res;
	char *local_buf;
	loff_t next_pos;
	char small_buf[32];	/* avoid kmalloc if we can */
	struct reiserfs_dir_entry de;
	int ret = 0;

	reiserfs_write_lock(inode->i_sb);

	reiserfs_check_lock_depth(inode->i_sb, "readdir");

	/* form key for search the next directory entry using f_pos field of
	   file structure */
	make_cpu_key(&pos_key, inode, *pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
	next_pos = cpu_key_k_offset(&pos_key);

	path_to_entry.reada = PATH_READA;
	while (1) {
	      research:
		/* search the directory item, containing entry with specified key */
		search_res =
		    search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
					&de);
		if (search_res == IO_ERROR) {
			// FIXME: we could just skip part of directory which could
			// not be read
			ret = -EIO;
			goto out;
		}
		entry_num = de.de_entry_num;
		bh = de.de_bh;
		item_num = de.de_item_num;
		ih = de.de_ih;
		store_ih(&tmp_ih, ih);

		/* we must have found item, that is item of this directory, */
		RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
		       "vs-9000: found item %h does not match to dir we readdir %K",
		       ih, &pos_key);
		RFALSE(item_num > B_NR_ITEMS(bh) - 1,
		       "vs-9005 item_num == %d, item amount == %d",
		       item_num, B_NR_ITEMS(bh));

		/* and entry must be not more than number of entries in the item */
		RFALSE(I_ENTRY_COUNT(ih) < entry_num,
		       "vs-9010: entry number is too big %d (%d)",
		       entry_num, I_ENTRY_COUNT(ih));

		if (search_res == POSITION_FOUND
		    || entry_num < I_ENTRY_COUNT(ih)) {
			/* go through all entries in the directory item beginning from the entry, that has been found */
			struct reiserfs_de_head *deh =
			    B_I_DEH(bh, ih) + entry_num;

			for (; entry_num < I_ENTRY_COUNT(ih);
			     entry_num++, deh++) {
				int d_reclen;
				char *d_name;
				off_t d_off;
				ino_t d_ino;
				loff_t cur_pos = deh_offset(deh);

				if (!de_visible(deh))
					/* it is hidden entry */
					continue;
				d_reclen = entry_length(bh, ih, entry_num);
				d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);

				if (d_reclen <= 0 ||
				    d_name + d_reclen > bh->b_data + bh->b_size) {
					/* There is corrupted data in entry,
					 * We'd better stop here */
					pathrelse(&path_to_entry);
					ret = -EIO;
					goto out;
				}

				if (!d_name[d_reclen - 1])
					d_reclen = strlen(d_name);

				if (d_reclen >
				    REISERFS_MAX_NAME(inode->i_sb->
						      s_blocksize)) {
					/* too big to send back to VFS */
					continue;
				}

				/* Ignore the .reiserfs_priv entry */
				if (is_privroot_deh(dentry, deh))
					continue;

				d_off = deh_offset(deh);
				*pos = d_off;
				d_ino = deh_objectid(deh);
				if (d_reclen <= 32) {
					local_buf = small_buf;
				} else {
					local_buf = kmalloc(d_reclen,
							    GFP_NOFS);
					if (!local_buf) {
						pathrelse(&path_to_entry);
						ret = -ENOMEM;
						goto out;
					}
					if (item_moved(&tmp_ih, &path_to_entry)) {
						kfree(local_buf);
						goto research;
					}
				}
				// Note, that we copy name to user space via temporary
				// buffer (local_buf) because filldir will block if
				// user space buffer is swapped out. At that time
				// entry can move to somewhere else
				memcpy(local_buf, d_name, d_reclen);

				/*
				 * Since filldir might sleep, we can release
				 * the write lock here for other waiters
				 */
				reiserfs_write_unlock(inode->i_sb);
				if (filldir
				    (dirent, local_buf, d_reclen, d_off, d_ino,
				     DT_UNKNOWN) < 0) {
					reiserfs_write_lock(inode->i_sb);
					if (local_buf != small_buf) {
						kfree(local_buf);
					}
					goto end;
				}
				reiserfs_write_lock(inode->i_sb);
				if (local_buf != small_buf) {
					kfree(local_buf);
				}

				/* deh_offset(deh) may be invalid now. */
				next_pos = cur_pos + 1;

				if (item_moved(&tmp_ih, &path_to_entry)) {
					set_cpu_key_k_offset(&pos_key,
							     next_pos);
					goto research;
				}
			}	/* for */
		}

		if (item_num != B_NR_ITEMS(bh) - 1)
			// end of directory has been reached
			goto end;

		/* item we went through is last item of node. Using right
		   delimiting key check is it directory end */
		rkey = get_rkey(&path_to_entry, inode->i_sb);
		if (!comp_le_keys(rkey, &MIN_KEY)) {
			/* set pos_key to key, that is the smallest and greater
			   that key of the last entry in the item */
			set_cpu_key_k_offset(&pos_key, next_pos);
			continue;
		}

		if (COMP_SHORT_KEYS(rkey, &pos_key)) {
			// end of directory has been reached
			goto end;
		}

		/* directory continues in the right neighboring block */
		set_cpu_key_k_offset(&pos_key,
				     le_key_k_offset(KEY_FORMAT_3_5, rkey));

	}			/* while */

end:
	*pos = next_pos;
	pathrelse(&path_to_entry);
	reiserfs_check_path(&path_to_entry);
out:
	reiserfs_write_unlock(inode->i_sb);
	return ret;
}