/*
- * linux/fs/transaction.c
+ * linux/fs/jbd2/transaction.c
*
* Written by Stephen C. Tweedie <sct@redhat.com>, 1998
*
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/timer.h>
-#include <linux/smp_lock.h>
#include <linux/mm.h>
#include <linux/highmem.h>
* new transaction and we can't block without protecting against other
* processes trying to touch the journal while it is in transition.
*
- * Called under j_state_lock
*/
static transaction_t *
transaction->t_tid = journal->j_transaction_sequence++;
transaction->t_expires = jiffies + journal->j_commit_interval;
spin_lock_init(&transaction->t_handle_lock);
+ INIT_LIST_HEAD(&transaction->t_inode_list);
/* Set up the commit timer for the new transaction. */
- journal->j_commit_timer.expires = transaction->t_expires;
+ journal->j_commit_timer.expires = round_jiffies(transaction->t_expires);
add_timer(&journal->j_commit_timer);
J_ASSERT(journal->j_running_transaction == NULL);
journal->j_running_transaction = transaction;
+ transaction->t_max_wait = 0;
+ transaction->t_start = jiffies;
return transaction;
}
int nblocks = handle->h_buffer_credits;
transaction_t *new_transaction = NULL;
int ret = 0;
+ unsigned long ts = jiffies;
if (nblocks > journal->j_max_transaction_buffers) {
printk(KERN_ERR "JBD: %s wants too many credits (%d > %d)\n",
alloc_transaction:
if (!journal->j_running_transaction) {
- new_transaction = jbd_kmalloc(sizeof(*new_transaction),
- GFP_NOFS);
+ new_transaction = kzalloc(sizeof(*new_transaction),
+ GFP_NOFS|__GFP_NOFAIL);
if (!new_transaction) {
ret = -ENOMEM;
goto out;
}
- memset(new_transaction, 0, sizeof(*new_transaction));
}
jbd_debug(3, "New handle %p going live.\n", handle);
/* OK, account for the buffers that this operation expects to
* use and add the handle to the running transaction. */
+ if (time_after(transaction->t_start, ts)) {
+ ts = jbd2_time_diff(ts, transaction->t_start);
+ if (ts > transaction->t_max_wait)
+ transaction->t_max_wait = ts;
+ }
+
handle->h_transaction = transaction;
transaction->t_outstanding_credits += nblocks;
transaction->t_updates++;
return ret;
}
+static struct lock_class_key jbd2_handle_key;
+
/* Allocate a new handle. This should probably be in a slab... */
static handle_t *new_handle(int nblocks)
{
- handle_t *handle = jbd_alloc_handle(GFP_NOFS);
+ handle_t *handle = jbd2_alloc_handle(GFP_NOFS);
if (!handle)
return NULL;
memset(handle, 0, sizeof(*handle));
handle->h_buffer_credits = nblocks;
handle->h_ref = 1;
+ lockdep_init_map(&handle->h_lockdep_map, "jbd2_handle",
+ &jbd2_handle_key, 0);
+
return handle;
}
err = start_this_handle(journal, handle);
if (err < 0) {
- jbd_free_handle(handle);
+ jbd2_free_handle(handle);
current->journal_info = NULL;
handle = ERR_PTR(err);
+ goto out;
}
+
+ lock_acquire(&handle->h_lockdep_map, 0, 0, 0, 2, _THIS_IP_);
+out:
return handle;
}
goto done;
/*
+ * this is the first time this transaction is touching this buffer,
+ * reset the modified flag
+ */
+ jh->b_modified = 0;
+
+ /*
* If there is already a copy-out version of this buffer, then we don't
* need to make another one
*/
JBUFFER_TRACE(jh, "allocate memory for buffer");
jbd_unlock_bh_state(bh);
frozen_buffer =
- jbd2_slab_alloc(jh2bh(jh)->b_size,
+ jbd2_alloc(jh2bh(jh)->b_size,
GFP_NOFS);
if (!frozen_buffer) {
printk(KERN_EMERG
"%s: OOM for frozen_buffer\n",
- __FUNCTION__);
+ __func__);
JBUFFER_TRACE(jh, "oom!");
error = -ENOMEM;
jbd_lock_bh_state(bh);
out:
if (unlikely(frozen_buffer)) /* It's usually NULL */
- jbd2_slab_free(frozen_buffer, bh->b_size);
+ jbd2_free(frozen_buffer, bh->b_size);
JBUFFER_TRACE(jh, "exit");
return error;
if (jh->b_transaction == NULL) {
jh->b_transaction = transaction;
+
+ /* first access by this transaction */
+ jh->b_modified = 0;
+
JBUFFER_TRACE(jh, "file as BJ_Reserved");
__jbd2_journal_file_buffer(jh, transaction, BJ_Reserved);
} else if (jh->b_transaction == journal->j_committing_transaction) {
+ /* first access by this transaction */
+ jh->b_modified = 0;
+
JBUFFER_TRACE(jh, "set next transaction");
jh->b_next_transaction = transaction;
}
repeat:
if (!jh->b_committed_data) {
- committed_data = jbd2_slab_alloc(jh2bh(jh)->b_size, GFP_NOFS);
+ committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS);
if (!committed_data) {
printk(KERN_EMERG "%s: No memory for committed data\n",
- __FUNCTION__);
+ __func__);
err = -ENOMEM;
goto out;
}
out:
jbd2_journal_put_journal_head(jh);
if (unlikely(committed_data))
- jbd2_slab_free(committed_data, bh->b_size);
+ jbd2_free(committed_data, bh->b_size);
return err;
}
/**
- * 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
}
/* That test should have eliminated the following case: */
- J_ASSERT_JH(jh, jh->b_frozen_data == 0);
+ J_ASSERT_JH(jh, jh->b_frozen_data == NULL);
JBUFFER_TRACE(jh, "file as BJ_Metadata");
spin_lock(&journal->j_list_lock);
struct journal_head *jh;
int drop_reserve = 0;
int err = 0;
+ int was_modified = 0;
BUFFER_TRACE(bh, "entry");
goto not_jbd;
}
+ /* keep track of wether or not this transaction modified us */
+ was_modified = jh->b_modified;
+
/*
* The buffer's going from the transaction, we must drop
* all references -bzzz
JBUFFER_TRACE(jh, "belongs to current transaction: unfile");
- drop_reserve = 1;
+ /*
+ * we only want to drop a reference if this transaction
+ * modified the buffer
+ */
+ if (was_modified)
+ drop_reserve = 1;
/*
* We are no longer going to journal this buffer.
if (jh->b_next_transaction) {
J_ASSERT(jh->b_next_transaction == transaction);
jh->b_next_transaction = NULL;
- drop_reserve = 1;
+
+ /*
+ * only drop a reference if this transaction modified
+ * the buffer
+ */
+ if (was_modified)
+ drop_reserve = 1;
}
}
spin_unlock(&journal->j_state_lock);
}
- jbd_free_handle(handle);
+ lock_release(&handle->h_lockdep_map, 1, _THIS_IP_);
+
+ jbd2_free_handle(handle);
return err;
}
-/**int jbd2_journal_force_commit() - force any uncommitted transactions
+/**
+ * int jbd2_journal_force_commit() - force any uncommitted transactions
* @journal: journal to force
*
* For synchronous operations: force any uncommitted transactions
* 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.
*/
J_ASSERT_JH(jh, jh->b_jlist < BJ_Types);
if (jh->b_jlist != BJ_None)
- J_ASSERT_JH(jh, transaction != 0);
+ J_ASSERT_JH(jh, transaction != NULL);
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);
case BJ_Reserved:
list = &transaction->t_reserved_list;
break;
- case BJ_Locked:
- list = &transaction->t_locked_list;
- break;
}
__blist_del_buffer(list, jh);
if (buffer_locked(bh) || buffer_dirty(bh))
goto out;
- if (jh->b_next_transaction != 0)
+ if (jh->b_next_transaction != NULL)
goto out;
spin_lock(&journal->j_list_lock);
- if (jh->b_transaction != 0 && jh->b_cp_transaction == 0) {
- 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 != 0 && jh->b_transaction == 0) {
+ 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");
return;
}
+/*
+ * jbd2_journal_try_to_free_buffers() could race with
+ * jbd2_journal_commit_transaction(). The later might still hold the
+ * reference count to the buffers when inspecting them on
+ * t_syncdata_list or t_locked_list.
+ *
+ * jbd2_journal_try_to_free_buffers() will call this function to
+ * wait for the current transaction to finish syncing data buffers, before
+ * try to free that buffer.
+ *
+ * Called with journal->j_state_lock hold.
+ */
+static void jbd2_journal_wait_for_transaction_sync_data(journal_t *journal)
+{
+ transaction_t *transaction;
+ tid_t tid;
+
+ spin_lock(&journal->j_state_lock);
+ transaction = journal->j_committing_transaction;
+
+ if (!transaction) {
+ spin_unlock(&journal->j_state_lock);
+ return;
+ }
+
+ tid = transaction->t_tid;
+ spin_unlock(&journal->j_state_lock);
+ jbd2_log_wait_commit(journal, tid);
+}
/**
* int jbd2_journal_try_to_free_buffers() - try to free page buffers.
* @journal: journal for operation
* @page: to try and free
- * @unused_gfp_mask: unused
+ * @gfp_mask: we use the mask to detect how hard should we try to release
+ * buffers. If __GFP_WAIT and __GFP_FS is set, we wait for commit code to
+ * release the buffers.
*
*
* For all the buffers on this page,
* journal_try_to_free_buffer() is changing its state. But that
* cannot happen because we never reallocate freed data as metadata
* while the data is part of a transaction. Yes?
+ *
+ * Return 0 on failure, 1 on success
*/
int jbd2_journal_try_to_free_buffers(journal_t *journal,
- struct page *page, gfp_t unused_gfp_mask)
+ struct page *page, gfp_t gfp_mask)
{
struct buffer_head *head;
struct buffer_head *bh;
/*
* We take our own ref against the journal_head here to avoid
* having to add tons of locking around each instance of
- * jbd2_journal_remove_journal_head() and jbd2_journal_put_journal_head().
+ * jbd2_journal_remove_journal_head() and
+ * jbd2_journal_put_journal_head().
*/
jh = jbd2_journal_grab_journal_head(bh);
if (!jh)
if (buffer_jbd(bh))
goto busy;
} while ((bh = bh->b_this_page) != head);
+
ret = try_to_free_buffers(page);
+
+ /*
+ * There are a number of places where jbd2_journal_try_to_free_buffers()
+ * could race with jbd2_journal_commit_transaction(), the later still
+ * holds the reference to the buffers to free while processing them.
+ * try_to_free_buffers() failed to free those buffers. Some of the
+ * caller of releasepage() request page buffers to be dropped, otherwise
+ * treat the fail-to-free as errors (such as generic_file_direct_IO())
+ *
+ * So, if the caller of try_to_release_page() wants the synchronous
+ * behaviour(i.e make sure buffers are dropped upon return),
+ * let's wait for the current transaction to finish flush of
+ * dirty data buffers, then try to free those buffers again,
+ * with the journal locked.
+ */
+ if (ret == 0 && (gfp_mask & __GFP_WAIT) && (gfp_mask & __GFP_FS)) {
+ jbd2_journal_wait_for_transaction_sync_data(journal);
+ ret = try_to_free_buffers(page);
+ }
+
busy:
return ret;
}
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);
}
} 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
J_ASSERT_JH(jh, jh->b_jlist < BJ_Types);
J_ASSERT_JH(jh, jh->b_transaction == transaction ||
- jh->b_transaction == 0);
+ jh->b_transaction == NULL);
if (jh->b_transaction && jh->b_jlist == jlist)
return;
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;
case BJ_Reserved:
list = &transaction->t_reserved_list;
break;
- case BJ_Locked:
- list = &transaction->t_locked_list;
- break;
}
__blist_add_buffer(list, jh);
jh->b_transaction = jh->b_next_transaction;
jh->b_next_transaction = NULL;
__jbd2_journal_file_buffer(jh, jh->b_transaction,
- was_dirty ? BJ_Metadata : BJ_Reserved);
+ jh->b_modified ? BJ_Metadata : BJ_Reserved);
J_ASSERT_JH(jh, jh->b_transaction->t_state == T_RUNNING);
if (was_dirty)
spin_unlock(&journal->j_list_lock);
__brelse(bh);
}
+
+/*
+ * File inode in the inode list of the handle's transaction
+ */
+int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *jinode)
+{
+ transaction_t *transaction = handle->h_transaction;
+ journal_t *journal = transaction->t_journal;
+
+ if (is_handle_aborted(handle))
+ return -EIO;
+
+ jbd_debug(4, "Adding inode %lu, tid:%d\n", jinode->i_vfs_inode->i_ino,
+ transaction->t_tid);
+
+ /*
+ * First check whether inode isn't already on the transaction's
+ * lists without taking the lock. Note that this check is safe
+ * without the lock as we cannot race with somebody removing inode
+ * from the transaction. The reason is that we remove inode from the
+ * transaction only in journal_release_jbd_inode() and when we commit
+ * the transaction. We are guarded from the first case by holding
+ * a reference to the inode. We are safe against the second case
+ * because if jinode->i_transaction == transaction, commit code
+ * cannot touch the transaction because we hold reference to it,
+ * and if jinode->i_next_transaction == transaction, commit code
+ * will only file the inode where we want it.
+ */
+ if (jinode->i_transaction == transaction ||
+ jinode->i_next_transaction == transaction)
+ return 0;
+
+ spin_lock(&journal->j_list_lock);
+
+ if (jinode->i_transaction == transaction ||
+ jinode->i_next_transaction == transaction)
+ goto done;
+
+ /* On some different transaction's list - should be
+ * the committing one */
+ if (jinode->i_transaction) {
+ J_ASSERT(jinode->i_next_transaction == NULL);
+ J_ASSERT(jinode->i_transaction ==
+ journal->j_committing_transaction);
+ jinode->i_next_transaction = transaction;
+ goto done;
+ }
+ /* Not on any transaction list... */
+ J_ASSERT(!jinode->i_next_transaction);
+ jinode->i_transaction = transaction;
+ list_add(&jinode->i_list, &transaction->t_inode_list);
+done:
+ spin_unlock(&journal->j_list_lock);
+
+ return 0;
+}
+
+/*
+ * This function must be called when inode is journaled in ordered mode
+ * before truncation happens. It starts writeout of truncated part in
+ * case it is in the committing transaction so that we stand to ordered
+ * mode consistency guarantees.
+ */
+int jbd2_journal_begin_ordered_truncate(struct jbd2_inode *inode,
+ loff_t new_size)
+{
+ journal_t *journal;
+ transaction_t *commit_trans;
+ int ret = 0;
+
+ if (!inode->i_transaction && !inode->i_next_transaction)
+ goto out;
+ journal = inode->i_transaction->t_journal;
+ spin_lock(&journal->j_state_lock);
+ commit_trans = journal->j_committing_transaction;
+ spin_unlock(&journal->j_state_lock);
+ if (inode->i_transaction == commit_trans) {
+ ret = filemap_fdatawrite_range(inode->i_vfs_inode->i_mapping,
+ new_size, LLONG_MAX);
+ if (ret)
+ jbd2_journal_abort(journal, ret);
+ }
+out:
+ return ret;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff