In data=journal mode, reiserfs writepage needs to make sure not to trigger transactions while being run under PF_MEMALLOC. This patch makes sure to redirty the page instead of forcing a transaction start in this case.
Also, calling filemap_fdata* in order to trigger io on the block device can cause lock inversions on the page lock. Instead, do simple batching from flush_commit_list. diff -r c10585019f18 fs/reiserfs/inode.c --- a/fs/reiserfs/inode.c Fri Jan 13 13:51:10 2006 -0500 +++ b/fs/reiserfs/inode.c Fri Jan 13 13:55:09 2006 -0500 @@ -2363,6 +2363,13 @@ static int reiserfs_write_full_page(stru int bh_per_page = PAGE_CACHE_SIZE / s->s_blocksize; th.t_trans_id = 0; + /* no logging allowed when nonblocking or from PF_MEMALLOC */ + if (checked && (current->flags & PF_MEMALLOC)) { + redirty_page_for_writepage(wbc, page); + unlock_page(page); + return 0; + } + /* The page dirty bit is cleared before writepage is called, which * means we have to tell create_empty_buffers to make dirty buffers * The page really should be up to date at this point, so tossing diff -r c10585019f18 fs/reiserfs/journal.c --- a/fs/reiserfs/journal.c Fri Jan 13 13:51:10 2006 -0500 +++ b/fs/reiserfs/journal.c Fri Jan 13 13:55:09 2006 -0500 @@ -990,6 +990,7 @@ static int flush_commit_list(struct supe struct reiserfs_journal *journal = SB_JOURNAL(s); int barrier = 0; int retval = 0; + int write_len; reiserfs_check_lock_depth(s, "flush_commit_list"); @@ -1039,16 +1040,24 @@ static int flush_commit_list(struct supe BUG_ON(!list_empty(&jl->j_bh_list)); /* * for the description block and all the log blocks, submit any buffers - * that haven't already reached the disk + * that haven't already reached the disk. Try to write at least 256 + * log blocks. later on, we will only wait on blocks that correspond + * to this transaction, but while we're unplugging we might as well + * get a chunk of data on there. */ atomic_inc(&journal->j_async_throttle); - for (i = 0; i < (jl->j_len + 1); i++) { + write_len = jl->j_len + 1; + if (write_len < 256) + write_len = 256; + for (i = 0 ; i < write_len ; i++) { bn = SB_ONDISK_JOURNAL_1st_BLOCK(s) + (jl->j_start + i) % SB_ONDISK_JOURNAL_SIZE(s); tbh = journal_find_get_block(s, bn); - if (buffer_dirty(tbh)) /* redundant, ll_rw_block() checks */ - ll_rw_block(SWRITE, 1, &tbh); - put_bh(tbh); + if (tbh) { + if (buffer_dirty(tbh)) + ll_rw_block(WRITE, 1, &tbh) ; + put_bh(tbh) ; + } } atomic_dec(&journal->j_async_throttle); --