On Monday 04 February 2008 5:12:28 am Aneesh Kumar K.V wrote: > Hi, > > This is with the new ext3 -> ext4 migrate code added. The recently added > lockdep for jbd2 helped to find this out. We want to hold the i_data_sem > on the ext3 inode during migration to prevent walking the ext3 inode > when it is being converted to ext4 format. Also we want to avoid > file truncation and new blocks being added while converting to ext4. > Also we dont want to reserve large number of credits for journal. > Any idea how to fix this ? > Hello, Seems you should be taking the i_data_sem after starting the journal in ext4_ext_migrate. I haven't looked at this stuff too much, but everywhere I see i_data_sem taken its within a journal_start/journal_stop. Here's the patch. Let me know if I'm way off btw, like I said I'm new to this :). Thank you, Josef Index: linux-2.6/fs/ext4/migrate.c =================================================================== --- linux-2.6.orig/fs/ext4/migrate.c +++ linux-2.6/fs/ext4/migrate.c @@ -414,7 +414,6 @@ int ext4_ext_migrate(struct inode *inode if ((EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) return -EINVAL; - down_write(&EXT4_I(inode)->i_data_sem); handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 + @@ -424,6 +423,9 @@ int ext4_ext_migrate(struct inode *inode retval = PTR_ERR(handle); goto err_out; } + + down_write(&EXT4_I(inode)->i_data_sem); + tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode, S_IFREG); @@ -549,10 +551,10 @@ err_out: */ tmp_inode->i_nlink = 0; - ext4_journal_stop(handle); - up_write(&EXT4_I(inode)->i_data_sem); + ext4_journal_stop(handle); + if (tmp_inode) iput(tmp_inode); - To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
