From: Jan Kara <jack@xxxxxxx> Date: Thu, 22 May 2008 01:28:16 +0200 Subject: [PATCH] jbd2: Remove data=ordered mode support using jbd buffer heads Signed-off-by: Jan Kara <jack@xxxxxxx> --- fs/jbd2/checkpoint.c | 1 - fs/jbd2/commit.c | 230 ++----------------------------------------------- fs/jbd2/journal.c | 1 - fs/jbd2/transaction.c | 217 ++--------------------------------------------- include/linux/jbd2.h | 29 ++----- 5 files changed, 21 insertions(+), 457 deletions(-) Index: linux-2.6-linus/fs/jbd2/checkpoint.c =================================================================== --- linux-2.6-linus.orig/fs/jbd2/checkpoint.c +++ linux-2.6-linus/fs/jbd2/checkpoint.c @@ -688,7 +688,6 @@ void __jbd2_journal_drop_transaction(jou J_ASSERT(transaction->t_state == T_FINISHED); J_ASSERT(transaction->t_buffers == NULL); - J_ASSERT(transaction->t_sync_datalist == NULL); J_ASSERT(transaction->t_forget == NULL); J_ASSERT(transaction->t_iobuf_list == NULL); J_ASSERT(transaction->t_shadow_list == NULL); Index: linux-2.6-linus/fs/jbd2/commit.c =================================================================== --- linux-2.6-linus.orig/fs/jbd2/commit.c +++ linux-2.6-linus/fs/jbd2/commit.c @@ -37,8 +37,8 @@ static void journal_end_buffer_io_sync(s } /* - * When an ext3-ordered file is truncated, it is possible that many pages are - * not sucessfully freed, because they are attached to a committing transaction. + * When an ext4 file is truncated, it is possible that some pages are not + * successfully freed, because they are attached to a committing transaction. * After the transaction commits, these pages are left on the LRU, with no * ->mapping, and with attached buffers. These pages are trivially reclaimable * by the VM, but their apparent absence upsets the VM accounting, and it makes @@ -80,21 +80,6 @@ nope: } /* - * Try to acquire jbd_lock_bh_state() against the buffer, when j_list_lock is - * held. For ranking reasons we must trylock. If we lose, schedule away and - * return 0. j_list_lock is dropped in this case. - */ -static int inverted_lock(journal_t *journal, struct buffer_head *bh) -{ - if (!jbd_trylock_bh_state(bh)) { - spin_unlock(&journal->j_list_lock); - schedule(); - return 0; - } - return 1; -} - -/* * Done it all: now submit the commit record. We should have * cleaned up our previous buffers by now, so if we are in abort * mode we can now just skip the rest of the journal write @@ -199,162 +184,6 @@ static int journal_wait_on_commit_record } /* - * Wait for all submitted IO to complete. - */ -static int journal_wait_on_locked_list(journal_t *journal, - transaction_t *commit_transaction) -{ - int ret = 0; - struct journal_head *jh; - - while (commit_transaction->t_locked_list) { - struct buffer_head *bh; - - jh = commit_transaction->t_locked_list->b_tprev; - bh = jh2bh(jh); - get_bh(bh); - if (buffer_locked(bh)) { - spin_unlock(&journal->j_list_lock); - wait_on_buffer(bh); - if (unlikely(!buffer_uptodate(bh))) - ret = -EIO; - spin_lock(&journal->j_list_lock); - } - if (!inverted_lock(journal, bh)) { - put_bh(bh); - spin_lock(&journal->j_list_lock); - continue; - } - if (buffer_jbd(bh) && jh->b_jlist == BJ_Locked) { - __jbd2_journal_unfile_buffer(jh); - jbd_unlock_bh_state(bh); - jbd2_journal_remove_journal_head(bh); - put_bh(bh); - } else { - jbd_unlock_bh_state(bh); - } - put_bh(bh); - cond_resched_lock(&journal->j_list_lock); - } - return ret; - } - -static void journal_do_submit_data(struct buffer_head **wbuf, int bufs) -{ - int i; - - for (i = 0; i < bufs; i++) { - wbuf[i]->b_end_io = end_buffer_write_sync; - /* We use-up our safety reference in submit_bh() */ - submit_bh(WRITE, wbuf[i]); - } -} - -/* - * Submit all the data buffers to disk - */ -static void journal_submit_data_buffers(journal_t *journal, - transaction_t *commit_transaction) -{ - struct journal_head *jh; - struct buffer_head *bh; - int locked; - int bufs = 0; - struct buffer_head **wbuf = journal->j_wbuf; - - /* - * Whenever we unlock the journal and sleep, things can get added - * onto ->t_sync_datalist, so we have to keep looping back to - * write_out_data until we *know* that the list is empty. - * - * Cleanup any flushed data buffers from the data list. Even in - * abort mode, we want to flush this out as soon as possible. - */ -write_out_data: - cond_resched(); - spin_lock(&journal->j_list_lock); - - while (commit_transaction->t_sync_datalist) { - jh = commit_transaction->t_sync_datalist; - bh = jh2bh(jh); - locked = 0; - - /* Get reference just to make sure buffer does not disappear - * when we are forced to drop various locks */ - get_bh(bh); - /* If the buffer is dirty, we need to submit IO and hence - * we need the buffer lock. We try to lock the buffer without - * blocking. If we fail, we need to drop j_list_lock and do - * blocking lock_buffer(). - */ - if (buffer_dirty(bh)) { - if (test_set_buffer_locked(bh)) { - BUFFER_TRACE(bh, "needs blocking lock"); - spin_unlock(&journal->j_list_lock); - /* Write out all data to prevent deadlocks */ - journal_do_submit_data(wbuf, bufs); - bufs = 0; - lock_buffer(bh); - spin_lock(&journal->j_list_lock); - } - locked = 1; - } - /* We have to get bh_state lock. Again out of order, sigh. */ - if (!inverted_lock(journal, bh)) { - jbd_lock_bh_state(bh); - spin_lock(&journal->j_list_lock); - } - /* Someone already cleaned up the buffer? */ - if (!buffer_jbd(bh) - || jh->b_transaction != commit_transaction - || jh->b_jlist != BJ_SyncData) { - jbd_unlock_bh_state(bh); - if (locked) - unlock_buffer(bh); - BUFFER_TRACE(bh, "already cleaned up"); - put_bh(bh); - continue; - } - if (locked && test_clear_buffer_dirty(bh)) { - BUFFER_TRACE(bh, "needs writeout, adding to array"); - wbuf[bufs++] = bh; - __jbd2_journal_file_buffer(jh, commit_transaction, - BJ_Locked); - jbd_unlock_bh_state(bh); - if (bufs == journal->j_wbufsize) { - spin_unlock(&journal->j_list_lock); - journal_do_submit_data(wbuf, bufs); - bufs = 0; - goto write_out_data; - } - } else if (!locked && buffer_locked(bh)) { - __jbd2_journal_file_buffer(jh, commit_transaction, - BJ_Locked); - jbd_unlock_bh_state(bh); - put_bh(bh); - } else { - BUFFER_TRACE(bh, "writeout complete: unfile"); - __jbd2_journal_unfile_buffer(jh); - jbd_unlock_bh_state(bh); - if (locked) - unlock_buffer(bh); - jbd2_journal_remove_journal_head(bh); - /* Once for our safety reference, once for - * jbd2_journal_remove_journal_head() */ - put_bh(bh); - put_bh(bh); - } - - if (need_resched() || spin_needbreak(&journal->j_list_lock)) { - spin_unlock(&journal->j_list_lock); - goto write_out_data; - } - } - spin_unlock(&journal->j_list_lock); - journal_do_submit_data(wbuf, bufs); -} - -/* * Submit all the data buffers of inode associated with the transaction to * disk. * @@ -601,42 +430,15 @@ void jbd2_journal_commit_transaction(jou * Now start flushing things to disk, in the order they appear * on the transaction lists. Data blocks go first. */ - err = 0; - journal_submit_data_buffers(journal, commit_transaction); err = journal_submit_inode_data_buffers(journal, commit_transaction); if (err) jbd2_journal_abort(journal, err); - /* - * Wait for all previously submitted IO to complete if commit - * record is to be written synchronously. - */ - spin_lock(&journal->j_list_lock); - if (!JBD2_HAS_INCOMPAT_FEATURE(journal, - JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) - err = journal_wait_on_locked_list(journal, - commit_transaction); - - spin_unlock(&journal->j_list_lock); - - if (err) - jbd2_journal_abort(journal, err); - jbd2_journal_write_revoke_records(journal, commit_transaction); jbd_debug(3, "JBD: commit phase 2\n"); /* - * If we found any dirty or locked buffers, then we should have - * looped back up to the write_out_data label. If there weren't - * any then journal_clean_data_list should have wiped the list - * clean by now, so check that it is in fact empty. - */ - J_ASSERT (commit_transaction->t_sync_datalist == NULL); - - jbd_debug (3, "JBD: commit phase 3\n"); - - /* * Way to go: we have now written out all of the data for a * transaction! Now comes the tricky part: we need to write out * metadata. Loop over the transaction's entire buffer list: @@ -654,6 +456,7 @@ void jbd2_journal_commit_transaction(jou J_ASSERT(commit_transaction->t_nr_buffers <= commit_transaction->t_outstanding_credits); + err = 0; descriptor = NULL; bufs = 0; while (commit_transaction->t_buffers) { @@ -828,13 +631,6 @@ start_journal_io: &cbh, crc32_sum); if (err) __jbd2_journal_abort_hard(journal); - - spin_lock(&journal->j_list_lock); - err = journal_wait_on_locked_list(journal, - commit_transaction); - spin_unlock(&journal->j_list_lock); - if (err) - __jbd2_journal_abort_hard(journal); } /* @@ -859,7 +655,7 @@ start_journal_io: so we incur less scheduling load. */ - jbd_debug(3, "JBD: commit phase 4\n"); + jbd_debug(3, "JBD: commit phase 3\n"); /* * akpm: these are BJ_IO, and j_list_lock is not needed. @@ -918,7 +714,7 @@ wait_for_iobuf: J_ASSERT (commit_transaction->t_shadow_list == NULL); - jbd_debug(3, "JBD: commit phase 5\n"); + jbd_debug(3, "JBD: commit phase 4\n"); /* Here we wait for the revoke record and descriptor record buffers */ wait_for_ctlbuf: @@ -945,7 +741,7 @@ wait_for_iobuf: /* AKPM: bforget here */ } - jbd_debug(3, "JBD: commit phase 6\n"); + jbd_debug(3, "JBD: commit phase 5\n"); if (!JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) { @@ -965,9 +761,8 @@ wait_for_iobuf: transaction can be removed from any checkpoint list it was on before. */ - jbd_debug(3, "JBD: commit phase 7\n"); + jbd_debug(3, "JBD: commit phase 6\n"); - J_ASSERT(commit_transaction->t_sync_datalist == NULL); J_ASSERT(list_empty(&commit_transaction->t_inode_list)); J_ASSERT(commit_transaction->t_buffers == NULL); J_ASSERT(commit_transaction->t_checkpoint_list == NULL); @@ -1089,7 +884,7 @@ restart_loop: /* Done with this transaction! */ - jbd_debug(3, "JBD: commit phase 8\n"); + jbd_debug(3, "JBD: commit phase 7\n"); J_ASSERT(commit_transaction->t_state == T_COMMIT); Index: linux-2.6-linus/fs/jbd2/journal.c =================================================================== --- linux-2.6-linus.orig/fs/jbd2/journal.c +++ linux-2.6-linus/fs/jbd2/journal.c @@ -50,7 +50,6 @@ EXPORT_SYMBOL(jbd2_journal_unlock_update EXPORT_SYMBOL(jbd2_journal_get_write_access); EXPORT_SYMBOL(jbd2_journal_get_create_access); EXPORT_SYMBOL(jbd2_journal_get_undo_access); -EXPORT_SYMBOL(jbd2_journal_dirty_data); EXPORT_SYMBOL(jbd2_journal_dirty_metadata); EXPORT_SYMBOL(jbd2_journal_release_buffer); EXPORT_SYMBOL(jbd2_journal_forget); Index: linux-2.6-linus/fs/jbd2/transaction.c =================================================================== --- linux-2.6-linus.orig/fs/jbd2/transaction.c +++ linux-2.6-linus/fs/jbd2/transaction.c @@ -943,183 +943,6 @@ out: } /** - * int jbd2_journal_dirty_data() - mark a buffer as containing dirty data which - * needs to be flushed before we can commit the - * current transaction. - * @handle: transaction - * @bh: bufferhead to mark - * - * The buffer is placed on the transaction's data list and is marked as - * belonging to the transaction. - * - * Returns error number or 0 on success. - * - * jbd2_journal_dirty_data() can be called via page_launder->ext3_writepage - * by kswapd. - */ -int jbd2_journal_dirty_data(handle_t *handle, struct buffer_head *bh) -{ - journal_t *journal = handle->h_transaction->t_journal; - int need_brelse = 0; - struct journal_head *jh; - - if (is_handle_aborted(handle)) - return 0; - - jh = jbd2_journal_add_journal_head(bh); - JBUFFER_TRACE(jh, "entry"); - - /* - * The buffer could *already* be dirty. Writeout can start - * at any time. - */ - jbd_debug(4, "jh: %p, tid:%d\n", jh, handle->h_transaction->t_tid); - - /* - * What if the buffer is already part of a running transaction? - * - * There are two cases: - * 1) It is part of the current running transaction. Refile it, - * just in case we have allocated it as metadata, deallocated - * it, then reallocated it as data. - * 2) It is part of the previous, still-committing transaction. - * If all we want to do is to guarantee that the buffer will be - * written to disk before this new transaction commits, then - * being sure that the *previous* transaction has this same - * property is sufficient for us! Just leave it on its old - * transaction. - * - * In case (2), the buffer must not already exist as metadata - * --- that would violate write ordering (a transaction is free - * to write its data at any point, even before the previous - * committing transaction has committed). The caller must - * never, ever allow this to happen: there's nothing we can do - * about it in this layer. - */ - jbd_lock_bh_state(bh); - spin_lock(&journal->j_list_lock); - - /* Now that we have bh_state locked, are we really still mapped? */ - if (!buffer_mapped(bh)) { - JBUFFER_TRACE(jh, "unmapped buffer, bailing out"); - goto no_journal; - } - - if (jh->b_transaction) { - JBUFFER_TRACE(jh, "has transaction"); - if (jh->b_transaction != handle->h_transaction) { - JBUFFER_TRACE(jh, "belongs to older transaction"); - J_ASSERT_JH(jh, jh->b_transaction == - journal->j_committing_transaction); - - /* @@@ IS THIS TRUE ? */ - /* - * Not any more. Scenario: someone does a write() - * in data=journal mode. The buffer's transaction has - * moved into commit. Then someone does another - * write() to the file. We do the frozen data copyout - * and set b_next_transaction to point to j_running_t. - * And while we're in that state, someone does a - * writepage() in an attempt to pageout the same area - * of the file via a shared mapping. At present that - * calls jbd2_journal_dirty_data(), and we get right here. - * It may be too late to journal the data. Simply - * falling through to the next test will suffice: the - * data will be dirty and wil be checkpointed. The - * ordering comments in the next comment block still - * apply. - */ - //J_ASSERT_JH(jh, jh->b_next_transaction == NULL); - - /* - * If we're journalling data, and this buffer was - * subject to a write(), it could be metadata, forget - * or shadow against the committing transaction. Now, - * someone has dirtied the same darn page via a mapping - * and it is being writepage()'d. - * We *could* just steal the page from commit, with some - * fancy locking there. Instead, we just skip it - - * don't tie the page's buffers to the new transaction - * at all. - * Implication: if we crash before the writepage() data - * is written into the filesystem, recovery will replay - * the write() data. - */ - if (jh->b_jlist != BJ_None && - jh->b_jlist != BJ_SyncData && - jh->b_jlist != BJ_Locked) { - JBUFFER_TRACE(jh, "Not stealing"); - goto no_journal; - } - - /* - * This buffer may be undergoing writeout in commit. We - * can't return from here and let the caller dirty it - * again because that can cause the write-out loop in - * commit to never terminate. - */ - if (buffer_dirty(bh)) { - get_bh(bh); - spin_unlock(&journal->j_list_lock); - jbd_unlock_bh_state(bh); - need_brelse = 1; - sync_dirty_buffer(bh); - jbd_lock_bh_state(bh); - spin_lock(&journal->j_list_lock); - /* Since we dropped the lock... */ - if (!buffer_mapped(bh)) { - JBUFFER_TRACE(jh, "buffer got unmapped"); - goto no_journal; - } - /* The buffer may become locked again at any - time if it is redirtied */ - } - - /* journal_clean_data_list() may have got there first */ - if (jh->b_transaction != NULL) { - JBUFFER_TRACE(jh, "unfile from commit"); - __jbd2_journal_temp_unlink_buffer(jh); - /* It still points to the committing - * transaction; move it to this one so - * that the refile assert checks are - * happy. */ - jh->b_transaction = handle->h_transaction; - } - /* The buffer will be refiled below */ - - } - /* - * Special case --- the buffer might actually have been - * allocated and then immediately deallocated in the previous, - * committing transaction, so might still be left on that - * transaction's metadata lists. - */ - if (jh->b_jlist != BJ_SyncData && jh->b_jlist != BJ_Locked) { - JBUFFER_TRACE(jh, "not on correct data list: unfile"); - J_ASSERT_JH(jh, jh->b_jlist != BJ_Shadow); - __jbd2_journal_temp_unlink_buffer(jh); - jh->b_transaction = handle->h_transaction; - JBUFFER_TRACE(jh, "file as data"); - __jbd2_journal_file_buffer(jh, handle->h_transaction, - BJ_SyncData); - } - } else { - JBUFFER_TRACE(jh, "not on a transaction"); - __jbd2_journal_file_buffer(jh, handle->h_transaction, BJ_SyncData); - } -no_journal: - spin_unlock(&journal->j_list_lock); - jbd_unlock_bh_state(bh); - if (need_brelse) { - BUFFER_TRACE(bh, "brelse"); - __brelse(bh); - } - JBUFFER_TRACE(jh, "exit"); - jbd2_journal_put_journal_head(jh); - return 0; -} - -/** * int jbd2_journal_dirty_metadata() - mark a buffer as containing dirty metadata * @handle: transaction to add buffer to. * @bh: buffer to mark @@ -1541,10 +1364,10 @@ __blist_del_buffer(struct journal_head * * Remove a buffer from the appropriate transaction list. * * Note that this function can *change* the value of - * bh->b_transaction->t_sync_datalist, t_buffers, t_forget, - * t_iobuf_list, t_shadow_list, t_log_list or t_reserved_list. If the caller - * is holding onto a copy of one of thee pointers, it could go bad. - * Generally the caller needs to re-read the pointer from the transaction_t. + * bh->b_transaction->t_buffers, t_forget, t_iobuf_list, t_shadow_list, + * t_log_list or t_reserved_list. If the caller is holding onto a copy of one + * of these pointers, it could go bad. Generally the caller needs to re-read + * the pointer from the transaction_t. * * Called under j_list_lock. The journal may not be locked. */ @@ -1566,9 +1389,6 @@ void __jbd2_journal_temp_unlink_buffer(s switch (jh->b_jlist) { case BJ_None: return; - case BJ_SyncData: - list = &transaction->t_sync_datalist; - break; case BJ_Metadata: transaction->t_nr_buffers--; J_ASSERT_JH(jh, transaction->t_nr_buffers >= 0); @@ -1589,9 +1409,6 @@ void __jbd2_journal_temp_unlink_buffer(s case BJ_Reserved: list = &transaction->t_reserved_list; break; - case BJ_Locked: - list = &transaction->t_locked_list; - break; } __blist_del_buffer(list, jh); @@ -1634,15 +1451,7 @@ __journal_try_to_free_buffer(journal_t * goto out; spin_lock(&journal->j_list_lock); - if (jh->b_transaction != NULL && jh->b_cp_transaction == NULL) { - if (jh->b_jlist == BJ_SyncData || jh->b_jlist == BJ_Locked) { - /* A written-back ordered data buffer */ - JBUFFER_TRACE(jh, "release data"); - __jbd2_journal_unfile_buffer(jh); - jbd2_journal_remove_journal_head(bh); - __brelse(bh); - } - } else if (jh->b_cp_transaction != NULL && jh->b_transaction == NULL) { + if (jh->b_cp_transaction != NULL && jh->b_transaction == NULL) { /* written-back checkpointed metadata buffer */ if (jh->b_jlist == BJ_None) { JBUFFER_TRACE(jh, "remove from checkpoint list"); @@ -1878,6 +1687,7 @@ static int journal_unmap_buffer(journal_ if (!buffer_jbd(bh)) goto zap_buffer_unlocked; + /* OK, we have data buffer in journaled mode */ spin_lock(&journal->j_state_lock); jbd_lock_bh_state(bh); spin_lock(&journal->j_list_lock); @@ -1941,15 +1751,6 @@ static int journal_unmap_buffer(journal_ } } else if (transaction == journal->j_committing_transaction) { JBUFFER_TRACE(jh, "on committing transaction"); - if (jh->b_jlist == BJ_Locked) { - /* - * The buffer is on the committing transaction's locked - * list. We have the buffer locked, so I/O has - * completed. So we can nail the buffer now. - */ - may_free = __dispose_buffer(jh, transaction); - goto zap_buffer; - } /* * If it is committing, we simply cannot touch it. We * can remove it's next_transaction pointer from the @@ -2082,9 +1883,6 @@ void __jbd2_journal_file_buffer(struct j J_ASSERT_JH(jh, !jh->b_committed_data); J_ASSERT_JH(jh, !jh->b_frozen_data); return; - case BJ_SyncData: - list = &transaction->t_sync_datalist; - break; case BJ_Metadata: transaction->t_nr_buffers++; list = &transaction->t_buffers; @@ -2104,9 +1902,6 @@ void __jbd2_journal_file_buffer(struct j case BJ_Reserved: list = &transaction->t_reserved_list; break; - case BJ_Locked: - list = &transaction->t_locked_list; - break; } __blist_add_buffer(list, jh); Index: linux-2.6-linus/include/linux/jbd2.h =================================================================== --- linux-2.6-linus.orig/include/linux/jbd2.h +++ linux-2.6-linus/include/linux/jbd2.h @@ -543,24 +543,12 @@ struct transaction_s struct journal_head *t_reserved_list; /* - * Doubly-linked circular list of all buffers under writeout during - * commit [j_list_lock] - */ - struct journal_head *t_locked_list; - - /* * Doubly-linked circular list of all metadata buffers owned by this * transaction [j_list_lock] */ struct journal_head *t_buffers; /* - * Doubly-linked circular list of all data buffers still to be - * flushed before this transaction can be committed [j_list_lock] - */ - struct journal_head *t_sync_datalist; - - /* * Doubly-linked circular list of all forget buffers (superseded * buffers which we can un-checkpoint once this transaction commits) * [j_list_lock] @@ -1041,7 +1029,6 @@ extern int jbd2_journal_extend (handle_ extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); -extern int jbd2_journal_dirty_data (handle_t *, struct buffer_head *); extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); extern void jbd2_journal_release_buffer (handle_t *, struct buffer_head *); extern int jbd2_journal_forget (handle_t *, struct buffer_head *); @@ -1220,15 +1207,13 @@ static inline int jbd_space_needed(journ /* journaling buffer types */ #define BJ_None 0 /* Not journaled */ -#define BJ_SyncData 1 /* Normal data: flush before commit */ -#define BJ_Metadata 2 /* Normal journaled metadata */ -#define BJ_Forget 3 /* Buffer superseded by this transaction */ -#define BJ_IO 4 /* Buffer is for temporary IO use */ -#define BJ_Shadow 5 /* Buffer contents being shadowed to the log */ -#define BJ_LogCtl 6 /* Buffer contains log descriptors */ -#define BJ_Reserved 7 /* Buffer is reserved for access by journal */ -#define BJ_Locked 8 /* Locked for I/O during commit */ -#define BJ_Types 9 +#define BJ_Metadata 1 /* Normal journaled metadata */ +#define BJ_Forget 2 /* Buffer superseded by this transaction */ +#define BJ_IO 3 /* Buffer is for temporary IO use */ +#define BJ_Shadow 4 /* Buffer contents being shadowed to the log */ +#define BJ_LogCtl 5 /* Buffer contains log descriptors */ +#define BJ_Reserved 6 /* Buffer is reserved for access by journal */ +#define BJ_Types 7 extern int jbd_blocks_per_page(struct inode *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