/*
* linux/fs/transaction.c
- *
+ *
* Written by Stephen C. Tweedie <sct@redhat.com>, 1998
*
* Copyright 1998 Red Hat corp --- All Rights Reserved
* option, any later version, incorporated herein by reference.
*
* Generic filesystem transaction handling code; part of the ext2fs
- * journaling system.
+ * journaling system.
*
* This file manages transactions (compound commits managed by the
* journaling code) and handles (individual atomic operations by the
#include <linux/mm.h>
#include <linux/highmem.h>
+static void __journal_temp_unlink_buffer(struct journal_head *jh);
+
/*
* get_transaction: obtain a new transaction_t object.
*
transaction->t_state = T_RUNNING;
transaction->t_tid = journal->j_transaction_sequence++;
transaction->t_expires = jiffies + journal->j_commit_interval;
- INIT_LIST_HEAD(&transaction->t_jcb);
spin_lock_init(&transaction->t_handle_lock);
- spin_lock_init(&transaction->t_jcb_lock);
/* Set up the commit timer for the new transaction. */
- journal->j_commit_timer->expires = transaction->t_expires;
- add_timer(journal->j_commit_timer);
+ 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;
* start_this_handle: Given a handle, deal with any locking or stalling
* needed to make sure that there is enough journal space for the handle
* to begin. Attach the handle to a transaction and set up the
- * transaction's buffer credits.
+ * transaction's buffer credits.
*/
static int start_this_handle(journal_t *journal, handle_t *handle)
if (is_journal_aborted(journal) ||
(journal->j_errno != 0 && !(journal->j_flags & JFS_ACK_ERR))) {
spin_unlock(&journal->j_state_lock);
- ret = -EROFS;
+ ret = -EROFS;
goto out;
}
goto repeat;
}
- /*
+ /*
* The commit code assumes that it can get enough log space
* without forcing a checkpoint. This is *critical* for
* correctness: a checkpoint of a buffer which is also
*
* We must therefore ensure the necessary space in the journal
* *before* starting to dirty potentially checkpointed buffers
- * in the new transaction.
+ * in the new transaction.
*
* The worst part is, any transaction currently committing can
* reduce the free space arbitrarily. Be careful to account for
spin_unlock(&transaction->t_handle_lock);
spin_unlock(&journal->j_state_lock);
out:
- if (new_transaction)
+ if (unlikely(new_transaction)) /* It's usually NULL */
kfree(new_transaction);
return ret;
}
memset(handle, 0, sizeof(*handle));
handle->h_buffer_credits = nblocks;
handle->h_ref = 1;
- INIT_LIST_HEAD(&handle->h_jcb);
return handle;
}
/**
- * handle_t *journal_start() - Obtain a new handle.
+ * handle_t *journal_start() - Obtain a new handle.
* @journal: Journal to start transaction on.
* @nblocks: number of block buffer we might modify
*
* We make sure that the transaction can guarantee at least nblocks of
* modified buffers in the log. We block until the log can guarantee
- * that much space.
+ * that much space.
*
* This function is visible to journal users (like ext3fs), so is not
* called with the journal already locked.
* int journal_extend() - extend buffer credits.
* @handle: handle to 'extend'
* @nblocks: nr blocks to try to extend by.
- *
+ *
* Some transactions, such as large extends and truncates, can be done
* atomically all at once or in several stages. The operation requests
* a credit for a number of buffer modications in advance, but can
- * extend its credit if it needs more.
+ * extend its credit if it needs more.
*
* journal_extend tries to give the running handle more buffer credits.
* It does not guarantee that allocation - this is a best-effort only.
* int journal_restart() - restart a handle .
* @handle: handle to restart
* @nblocks: nr credits requested
- *
+ *
* Restart a handle for a multi-transaction filesystem
* operation.
*
* to make sure that we serialise special journal-locked operations
* too.
*/
- down(&journal->j_barrier);
+ mutex_lock(&journal->j_barrier);
}
/**
* void journal_unlock_updates (journal_t* journal) - release barrier
* @journal: Journal to release the barrier on.
- *
+ *
* Release a transaction barrier obtained with journal_lock_updates().
*
* Should be called without the journal lock held.
{
J_ASSERT(journal->j_barrier_count != 0);
- up(&journal->j_barrier);
+ mutex_unlock(&journal->j_barrier);
spin_lock(&journal->j_state_lock);
--journal->j_barrier_count;
spin_unlock(&journal->j_state_lock);
*/
static void jbd_unexpected_dirty_buffer(struct journal_head *jh)
{
- struct buffer_head *bh = jh2bh(jh);
int jlist;
- if (buffer_dirty(bh)) {
- /* If this buffer is one which might reasonably be dirty
- * --- ie. data, or not part of this journal --- then
- * we're OK to leave it alone, but otherwise we need to
- * move the dirty bit to the journal's own internal
- * JBDDirty bit. */
- jlist = jh->b_jlist;
-
- if (jlist == BJ_Metadata || jlist == BJ_Reserved ||
- jlist == BJ_Shadow || jlist == BJ_Forget) {
- if (test_clear_buffer_dirty(jh2bh(jh))) {
- set_bit(BH_JBDDirty, &jh2bh(jh)->b_state);
- }
- }
+ /* If this buffer is one which might reasonably be dirty
+ * --- ie. data, or not part of this journal --- then
+ * we're OK to leave it alone, but otherwise we need to
+ * move the dirty bit to the journal's own internal
+ * JBDDirty bit. */
+ jlist = jh->b_jlist;
+
+ if (jlist == BJ_Metadata || jlist == BJ_Reserved ||
+ jlist == BJ_Shadow || jlist == BJ_Forget) {
+ struct buffer_head *bh = jh2bh(jh);
+
+ if (test_clear_buffer_dirty(bh))
+ set_buffer_jbddirty(bh);
}
}
*/
static int
do_get_write_access(handle_t *handle, struct journal_head *jh,
- int force_copy, int *credits)
+ int force_copy)
{
struct buffer_head *bh;
transaction_t *transaction;
jbd_lock_bh_state(bh);
/* We now hold the buffer lock so it is safe to query the buffer
- * state. Is the buffer dirty?
- *
+ * state. Is the buffer dirty?
+ *
* If so, there are two possibilities. The buffer may be
* non-journaled, and undergoing a quite legitimate writeback.
* Otherwise, it is journaled, and we don't expect dirty buffers
*/
if (jh->b_transaction) {
J_ASSERT_JH(jh,
- jh->b_transaction == transaction ||
+ jh->b_transaction == transaction ||
jh->b_transaction ==
journal->j_committing_transaction);
if (jh->b_next_transaction)
J_ASSERT_JH(jh, jh->b_next_transaction ==
transaction);
- JBUFFER_TRACE(jh, "Unexpected dirty buffer");
- jbd_unexpected_dirty_buffer(jh);
- }
- }
+ }
+ /*
+ * In any case we need to clean the dirty flag and we must
+ * do it under the buffer lock to be sure we don't race
+ * with running write-out.
+ */
+ JBUFFER_TRACE(jh, "Unexpected dirty buffer");
+ jbd_unexpected_dirty_buffer(jh);
+ }
unlock_buffer(bh);
JBUFFER_TRACE(jh, "has frozen data");
J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
jh->b_next_transaction = transaction;
-
- J_ASSERT_JH(jh, handle->h_buffer_credits > 0);
- handle->h_buffer_credits--;
- if (credits)
- (*credits)++;
goto done;
}
* disk then we cannot do copy-out here. */
if (jh->b_jlist == BJ_Shadow) {
+ DEFINE_WAIT_BIT(wait, &bh->b_state, BH_Unshadow);
wait_queue_head_t *wqh;
- DEFINE_WAIT(wait);
+
+ wqh = bit_waitqueue(&bh->b_state, BH_Unshadow);
JBUFFER_TRACE(jh, "on shadow: sleep");
jbd_unlock_bh_state(bh);
/* commit wakes up all shadow buffers after IO */
- wqh = bh_waitq_head(bh);
for ( ; ; ) {
- prepare_to_wait(wqh, &wait,
+ prepare_to_wait(wqh, &wait.wait,
TASK_UNINTERRUPTIBLE);
if (jh->b_jlist != BJ_Shadow)
break;
schedule();
}
- finish_wait(wqh, &wait);
+ finish_wait(wqh, &wait.wait);
goto repeat;
}
* buffer had better remain locked during the kmalloc,
* but that should be true --- we hold the journal lock
* still and the buffer is already on the BUF_JOURNAL
- * list so won't be flushed.
+ * list so won't be flushed.
*
* Subtle point, though: if this is a get_undo_access,
* then we will be relying on the frozen_data to contain
if (!frozen_buffer) {
JBUFFER_TRACE(jh, "allocate memory for buffer");
jbd_unlock_bh_state(bh);
- frozen_buffer = jbd_kmalloc(jh2bh(jh)->b_size,
- GFP_NOFS);
+ frozen_buffer =
+ jbd_slab_alloc(jh2bh(jh)->b_size,
+ GFP_NOFS);
if (!frozen_buffer) {
printk(KERN_EMERG
"%s: OOM for frozen_buffer\n",
jh->b_next_transaction = transaction;
}
- J_ASSERT(handle->h_buffer_credits > 0);
- handle->h_buffer_credits--;
- if (credits)
- (*credits)++;
/*
* Finally, if the buffer is not journaled right now, we need to make
journal_cancel_revoke(handle, jh);
out:
- if (frozen_buffer)
- kfree(frozen_buffer);
+ if (unlikely(frozen_buffer)) /* It's usually NULL */
+ jbd_slab_free(frozen_buffer, bh->b_size);
JBUFFER_TRACE(jh, "exit");
return error;
* int journal_get_write_access() - notify intent to modify a buffer for metadata (not data) update.
* @handle: transaction to add buffer modifications to
* @bh: bh to be used for metadata writes
+ * @credits: variable that will receive credits for the buffer
*
* Returns an error code or 0 on success.
*
* because we're write()ing a buffer which is also part of a shared mapping.
*/
-int journal_get_write_access(handle_t *handle,
- struct buffer_head *bh, int *credits)
+int journal_get_write_access(handle_t *handle, struct buffer_head *bh)
{
struct journal_head *jh = journal_add_journal_head(bh);
int rc;
/* We do not want to get caught playing with fields which the
* log thread also manipulates. Make sure that the buffer
* completes any outstanding IO before proceeding. */
- rc = do_get_write_access(handle, jh, 0, credits);
+ rc = do_get_write_access(handle, jh, 0);
journal_put_journal_head(jh);
return rc;
}
* manually rather than reading off disk), then we need to keep the
* buffer_head locked until it has been completely filled with new
* data. In this case, we should be able to make the assertion that
- * the bh is not already part of an existing transaction.
- *
+ * the bh is not already part of an existing transaction.
+ *
* The buffer should already be locked by the caller by this point.
* There is no lock ranking violation: it was a newly created,
* unlocked buffer beforehand. */
*
* Call this if you create a new bh.
*/
-int journal_get_create_access(handle_t *handle, struct buffer_head *bh)
+int journal_get_create_access(handle_t *handle, struct buffer_head *bh)
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal = transaction->t_journal;
J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
J_ASSERT_JH(jh, buffer_locked(jh2bh(jh)));
- J_ASSERT_JH(jh, handle->h_buffer_credits > 0);
- handle->h_buffer_credits--;
-
if (jh->b_transaction == NULL) {
jh->b_transaction = transaction;
JBUFFER_TRACE(jh, "file as BJ_Reserved");
* do not reuse freed space until the deallocation has been committed,
* since if we overwrote that space we would make the delete
* un-rewindable in case of a crash.
- *
+ *
* To deal with that, journal_get_undo_access requests write access to a
* buffer for parts of non-rewindable operations such as delete
* operations on the bitmaps. The journaling code must keep a copy of
* the buffer's contents prior to the undo_access call until such time
* as we know that the buffer has definitely been committed to disk.
- *
+ *
* We never need to know which transaction the committed data is part
* of, buffers touched here are guaranteed to be dirtied later and so
* will be committed to a new transaction in due course, at which point
*
* Returns error number or 0 on success.
*/
-int journal_get_undo_access(handle_t *handle, struct buffer_head *bh,
- int *credits)
+int journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
{
int err;
struct journal_head *jh = journal_add_journal_head(bh);
* make sure that obtaining the committed_data is done
* atomically wrt. completion of any outstanding commits.
*/
- err = do_get_write_access(handle, jh, 1, credits);
+ err = do_get_write_access(handle, jh, 1);
if (err)
goto out;
repeat:
if (!jh->b_committed_data) {
- committed_data = jbd_kmalloc(jh2bh(jh)->b_size, GFP_NOFS);
+ committed_data = jbd_slab_alloc(jh2bh(jh)->b_size, GFP_NOFS);
if (!committed_data) {
printk(KERN_EMERG "%s: No memory for committed data\n",
__FUNCTION__);
jbd_unlock_bh_state(bh);
out:
journal_put_journal_head(jh);
- if (committed_data)
- kfree(committed_data);
+ if (unlikely(committed_data))
+ jbd_slab_free(committed_data, bh->b_size);
return err;
}
-/**
+/**
* int journal_dirty_data() - mark a buffer as containing dirty data which
* needs to be flushed before we can commit the
- * current transaction.
+ * 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.
*
/*
* 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.
+ * 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
+ * being sure that the *previous* transaction has this same
* property is sufficient for us! Just leave it on its old
* transaction.
*
*/
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) {
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");
- __journal_unfile_buffer(jh);
+ __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 */
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);
- __journal_unfile_buffer(jh);
+ __journal_temp_unlink_buffer(jh);
+ jh->b_transaction = handle->h_transaction;
JBUFFER_TRACE(jh, "file as data");
__journal_file_buffer(jh, handle->h_transaction,
BJ_SyncData);
return 0;
}
-/**
+/**
* int journal_dirty_metadata() - mark a buffer as containing dirty metadata
* @handle: transaction to add buffer to.
- * @bh: buffer to mark
- *
+ * @bh: buffer to mark
+ *
* mark dirty metadata which needs to be journaled as part of the current
* transaction.
*
* The buffer is placed on the transaction's metadata list and is marked
- * as belonging to the transaction.
+ * as belonging to the transaction.
*
- * Returns error number or 0 on success.
+ * Returns error number or 0 on success.
*
* Special care needs to be taken if the buffer already belongs to the
* current committing transaction (in which case we should have frozen
jbd_lock_bh_state(bh);
+ if (jh->b_modified == 0) {
+ /*
+ * This buffer's got modified and becoming part
+ * of the transaction. This needs to be done
+ * once a transaction -bzzz
+ */
+ jh->b_modified = 1;
+ J_ASSERT_JH(jh, handle->h_buffer_credits > 0);
+ handle->h_buffer_credits--;
+ }
+
/*
* fastpath, to avoid expensive locking. If this buffer is already
* on the running transaction's metadata list there is nothing to do.
set_buffer_jbddirty(bh);
- /*
+ /*
* Metadata already on the current transaction list doesn't
* need to be filed. Metadata on another transaction's list must
* be committing, and will be refiled once the commit completes:
- * leave it alone for now.
+ * leave it alone for now.
*/
if (jh->b_transaction != transaction) {
JBUFFER_TRACE(jh, "already on other transaction");
return 0;
}
-/*
+/*
* journal_release_buffer: undo a get_write_access without any buffer
* updates, if the update decided in the end that it didn't need access.
*
- * The caller passes in the number of credits which should be put back for
- * this buffer (zero or one).
- *
- * We leave the buffer attached to t_reserved_list because even though this
- * handle doesn't want it, some other concurrent handle may want to journal
- * this buffer. If that handle is curently in between get_write_access() and
- * journal_dirty_metadata() then it expects the buffer to be reserved. If
- * we were to rip it off t_reserved_list here, the other handle will explode
- * when journal_dirty_metadata is presented with a non-reserved buffer.
- *
- * If nobody really wants to journal this buffer then it will be thrown
- * away at the start of commit.
*/
void
-journal_release_buffer(handle_t *handle, struct buffer_head *bh, int credits)
+journal_release_buffer(handle_t *handle, struct buffer_head *bh)
{
BUFFER_TRACE(bh, "entry");
- handle->h_buffer_credits += credits;
}
-/**
+/**
* void journal_forget() - bforget() for potentially-journaled buffers.
* @handle: transaction handle
* @bh: bh to 'forget'
*
* We can only do the bforget if there are no commits pending against the
* buffer. If the buffer is dirty in the current running transaction we
- * can safely unlink it.
+ * can safely unlink it.
*
* bh may not be a journalled buffer at all - it may be a non-JBD
* buffer which came off the hashtable. Check for this.
*
* Decrements bh->b_count by one.
- *
+ *
* Allow this call even if the handle has aborted --- it may be part of
* the caller's cleanup after an abort.
*/
-void journal_forget(handle_t *handle, struct buffer_head *bh)
+int journal_forget (handle_t *handle, struct buffer_head *bh)
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal = transaction->t_journal;
struct journal_head *jh;
+ int drop_reserve = 0;
+ int err = 0;
BUFFER_TRACE(bh, "entry");
goto not_jbd;
jh = bh2jh(bh);
+ /* Critical error: attempting to delete a bitmap buffer, maybe?
+ * Don't do any jbd operations, and return an error. */
+ if (!J_EXPECT_JH(jh, !jh->b_committed_data,
+ "inconsistent data on disk")) {
+ err = -EIO;
+ goto not_jbd;
+ }
+
+ /*
+ * The buffer's going from the transaction, we must drop
+ * all references -bzzz
+ */
+ jh->b_modified = 0;
+
if (jh->b_transaction == handle->h_transaction) {
J_ASSERT_JH(jh, !jh->b_frozen_data);
clear_buffer_jbddirty(bh);
JBUFFER_TRACE(jh, "belongs to current transaction: unfile");
- J_ASSERT_JH(jh, !jh->b_committed_data);
- __journal_unfile_buffer(jh);
+ drop_reserve = 1;
- /*
+ /*
* We are no longer going to journal this buffer.
* However, the commit of this transaction is still
* important to the buffer: the delete that we are now
*
* So, if we have a checkpoint on the buffer, we should
* now refile the buffer on our BJ_Forget list so that
- * we know to remove the checkpoint after we commit.
+ * we know to remove the checkpoint after we commit.
*/
if (jh->b_cp_transaction) {
+ __journal_temp_unlink_buffer(jh);
__journal_file_buffer(jh, transaction, BJ_Forget);
} else {
+ __journal_unfile_buffer(jh);
journal_remove_journal_head(bh);
__brelse(bh);
if (!buffer_jbd(bh)) {
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
__bforget(bh);
- return;
+ goto drop;
}
}
} else if (jh->b_transaction) {
- J_ASSERT_JH(jh, (jh->b_transaction ==
+ J_ASSERT_JH(jh, (jh->b_transaction ==
journal->j_committing_transaction));
/* However, if the buffer is still owned by a prior
* (committing) transaction, we can't drop it yet... */
if (jh->b_next_transaction) {
J_ASSERT(jh->b_next_transaction == transaction);
jh->b_next_transaction = NULL;
+ drop_reserve = 1;
}
}
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
__brelse(bh);
- return;
-}
-
-/**
- * void journal_callback_set() - Register a callback function for this handle.
- * @handle: handle to attach the callback to.
- * @func: function to callback.
- * @jcb: structure with additional information required by func() , and
- * some space for jbd internal information.
- *
- * The function will be
- * called when the transaction that this handle is part of has been
- * committed to disk with the original callback data struct and the
- * error status of the journal as parameters. There is no guarantee of
- * ordering between handles within a single transaction, nor between
- * callbacks registered on the same handle.
- *
- * The caller is responsible for allocating the journal_callback struct.
- * This is to allow the caller to add as much extra data to the callback
- * as needed, but reduce the overhead of multiple allocations. The caller
- * allocated struct must start with a struct journal_callback at offset 0,
- * and has the caller-specific data afterwards.
- */
-void journal_callback_set(handle_t *handle,
- void (*func)(struct journal_callback *jcb, int error),
- struct journal_callback *jcb)
-{
- spin_lock(&handle->h_transaction->t_jcb_lock);
- list_add_tail(&jcb->jcb_list, &handle->h_jcb);
- spin_unlock(&handle->h_transaction->t_jcb_lock);
- jcb->jcb_func = func;
+drop:
+ if (drop_reserve) {
+ /* no need to reserve log space for this block -bzzz */
+ handle->h_buffer_credits++;
+ }
+ return err;
}
/**
* int journal_stop() - complete a transaction
* @handle: tranaction to complete.
- *
+ *
* All done for a particular handle.
*
* There is not much action needed here. We just return any remaining
* filesystem is marked for synchronous update.
*
* journal_stop itself will not usually return an error, but it may
- * do so in unusual circumstances. In particular, expect it to
+ * do so in unusual circumstances. In particular, expect it to
* return -EIO if a journal_abort has been executed since the
* transaction began.
*/
transaction_t *transaction = handle->h_transaction;
journal_t *journal = transaction->t_journal;
int old_handle_count, err;
+ pid_t pid;
- J_ASSERT(transaction->t_updates > 0);
J_ASSERT(journal_current_handle() == handle);
if (is_handle_aborted(handle))
err = -EIO;
- else
+ else {
+ J_ASSERT(transaction->t_updates > 0);
err = 0;
+ }
if (--handle->h_ref > 0) {
jbd_debug(4, "h_ref %d -> %d\n", handle->h_ref + 1,
* It doesn't cost much - we're about to run a commit and sleep
* on IO anyway. Speeds up many-threaded, many-dir operations
* by 30x or more...
+ *
+ * But don't do this if this process was the most recent one to
+ * perform a synchronous write. We do this to detect the case where a
+ * single process is doing a stream of sync writes. No point in waiting
+ * for joiners in that case.
*/
- if (handle->h_sync) {
+ pid = current->pid;
+ if (handle->h_sync && journal->j_last_sync_writer != pid) {
+ journal->j_last_sync_writer = pid;
do {
old_handle_count = transaction->t_handle_count;
- set_current_state(TASK_UNINTERRUPTIBLE);
- schedule_timeout(1);
+ schedule_timeout_uninterruptible(1);
} while (old_handle_count != transaction->t_handle_count);
}
wake_up(&journal->j_wait_transaction_locked);
}
- /* Move callbacks from the handle to the transaction. */
- spin_lock(&transaction->t_jcb_lock);
- list_splice(&handle->h_jcb, &transaction->t_jcb);
- spin_unlock(&transaction->t_jcb_lock);
-
/*
* If the handle is marked SYNC, we need to set another commit
* going! We also want to force a commit if the current
if (handle->h_sync ||
transaction->t_outstanding_credits >
journal->j_max_transaction_buffers ||
- time_after_eq(jiffies, transaction->t_expires)) {
+ time_after_eq(jiffies, transaction->t_expires)) {
/* Do this even for aborted journals: an abort still
* completes the commit thread, it just doesn't write
* anything to disk. */
/*
* Special case: JFS_SYNC synchronous updates require us
- * to wait for the commit to complete.
+ * to wait for the commit to complete.
*/
if (handle->h_sync && !(current->flags & PF_MEMALLOC))
err = log_wait_commit(journal, tid);
* jbd_lock_bh_state(jh2bh(jh)) is held.
*/
-static inline void
+static inline void
__blist_add_buffer(struct journal_head **list, struct journal_head *jh)
{
if (!*list) {
}
}
-/*
+/*
* Remove a buffer from a transaction list, given the transaction's list
* head pointer.
*
jh->b_tnext->b_tprev = jh->b_tprev;
}
-/*
+/*
* Remove a buffer from the appropriate transaction list.
*
* Note that this function can *change* the value of
*
* Called under j_list_lock. The journal may not be locked.
*/
-void __journal_unfile_buffer(struct journal_head *jh)
+static void __journal_temp_unlink_buffer(struct journal_head *jh)
{
struct journal_head **list = NULL;
transaction_t *transaction;
switch (jh->b_jlist) {
case BJ_None:
- goto out;
+ return;
case BJ_SyncData:
list = &transaction->t_sync_datalist;
break;
jh->b_jlist = BJ_None;
if (test_clear_buffer_jbddirty(bh))
mark_buffer_dirty(bh); /* Expose it to the VM */
-out:
+}
+
+void __journal_unfile_buffer(struct journal_head *jh)
+{
+ __journal_temp_unlink_buffer(jh);
jh->b_transaction = NULL;
}
}
-/**
+/**
* int journal_try_to_free_buffers() - try to free page buffers.
* @journal: journal for operation
* @page: to try and free
- * @gfp_mask: 'IO' mode for try_to_free_buffers()
+ * @unused_gfp_mask: unused
+ *
*
- *
* For all the buffers on this page,
* if they are fully written out ordered data, move them onto BUF_CLEAN
* so try_to_free_buffers() can reap them.
- *
+ *
* This function returns non-zero if we wish try_to_free_buffers()
* to be called. We do this if the page is releasable by try_to_free_buffers().
* We also do it if the page has locked or dirty buffers and the caller wants
* cannot happen because we never reallocate freed data as metadata
* while the data is part of a transaction. Yes?
*/
-int journal_try_to_free_buffers(journal_t *journal,
- struct page *page, int unused_gfp_mask)
+int journal_try_to_free_buffers(journal_t *journal,
+ struct page *page, gfp_t unused_gfp_mask)
{
struct buffer_head *head;
struct buffer_head *bh;
}
/*
- * journal_invalidatepage
+ * journal_invalidatepage
*
* This code is tricky. It has a number of cases to deal with.
*
*
* i_size must be updated on disk before we start calling invalidatepage on the
* data.
- *
+ *
* This is done in ext3 by defining an ext3_setattr method which
* updates i_size before truncate gets going. By maintaining this
* invariant, we can be sure that it is safe to throw away any buffers
* attached to the current transaction: once the transaction commits,
* we know that the data will not be needed.
- *
+ *
* Note however that we can *not* throw away data belonging to the
- * previous, committing transaction!
+ * previous, committing transaction!
*
* Any disk blocks which *are* part of the previous, committing
* transaction (and which therefore cannot be discarded immediately) are
* don't make guarantees about the order in which data hits disk --- in
* particular we don't guarantee that new dirty data is flushed before
* transaction commit --- so it is always safe just to discard data
- * immediately in that mode. --sct
+ * immediately in that mode. --sct
*/
/*
JBUFFER_TRACE(jh, "checkpointed: add to BJ_Forget");
ret = __dispose_buffer(jh,
journal->j_running_transaction);
+ journal_put_journal_head(jh);
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
spin_unlock(&journal->j_state_lock);
- journal_put_journal_head(jh);
return ret;
} else {
/* There is no currently-running transaction. So the
JBUFFER_TRACE(jh, "give to committing trans");
ret = __dispose_buffer(jh,
journal->j_committing_transaction);
+ journal_put_journal_head(jh);
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
spin_unlock(&journal->j_state_lock);
- journal_put_journal_head(jh);
return ret;
} else {
/* The orphan record's transaction has
}
}
} else if (transaction == journal->j_committing_transaction) {
- /* If it is committing, we simply cannot touch it. We
+ 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
* running transaction if that is set, but nothing
* else. */
- JBUFFER_TRACE(jh, "on committing transaction");
set_buffer_freed(bh);
if (jh->b_next_transaction) {
J_ASSERT(jh->b_next_transaction ==
journal->j_running_transaction);
jh->b_next_transaction = NULL;
}
+ journal_put_journal_head(jh);
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
spin_unlock(&journal->j_state_lock);
- journal_put_journal_head(jh);
return 0;
} else {
/* Good, the buffer belongs to the running transaction.
* i_size already for this truncate so recovery will not
* expose the disk blocks we are discarding here.) */
J_ASSERT_JH(jh, transaction == journal->j_running_transaction);
+ JBUFFER_TRACE(jh, "on running transaction");
may_free = __dispose_buffer(jh, transaction);
}
return may_free;
}
-/**
- * int journal_invalidatepage()
- * @journal: journal to use for flush...
+/**
+ * void journal_invalidatepage()
+ * @journal: journal to use for flush...
* @page: page to flush
* @offset: length of page to invalidate.
*
* Reap page buffers containing data after offset in page.
*
- * Return non-zero if the page's buffers were successfully reaped.
*/
-int journal_invalidatepage(journal_t *journal,
- struct page *page,
+void journal_invalidatepage(journal_t *journal,
+ struct page *page,
unsigned long offset)
{
struct buffer_head *head, *bh, *next;
if (!PageLocked(page))
BUG();
if (!page_has_buffers(page))
- return 1;
+ return;
/* We will potentially be playing with lists other than just the
* data lists (especially for journaled data mode), so be
unsigned int next_off = curr_off + bh->b_size;
next = bh->b_this_page;
- /* AKPM: doing lock_buffer here may be overly paranoid */
if (offset <= curr_off) {
- /* This block is wholly outside the truncation point */
+ /* This block is wholly outside the truncation point */
lock_buffer(bh);
may_free &= journal_unmap_buffer(journal, bh);
unlock_buffer(bh);
} while (bh != head);
if (!offset) {
- if (!may_free || !try_to_free_buffers(page))
- return 0;
- J_ASSERT(!page_has_buffers(page));
+ if (may_free && try_to_free_buffers(page))
+ J_ASSERT(!page_has_buffers(page));
}
- return 1;
}
-/*
- * File a buffer on the given transaction list.
+/*
+ * File a buffer on the given transaction list.
*/
void __journal_file_buffer(struct journal_head *jh,
transaction_t *transaction, int jlist)
* with __jbd_unexpected_dirty_buffer()'s handling of dirty
* state. */
- if (jlist == BJ_Metadata || jlist == BJ_Reserved ||
+ if (jlist == BJ_Metadata || jlist == BJ_Reserved ||
jlist == BJ_Shadow || jlist == BJ_Forget) {
if (test_clear_buffer_dirty(bh) ||
test_clear_buffer_jbddirty(bh))
}
if (jh->b_transaction)
- __journal_unfile_buffer(jh);
+ __journal_temp_unlink_buffer(jh);
jh->b_transaction = transaction;
switch (jlist) {
jbd_unlock_bh_state(jh2bh(jh));
}
-/*
+/*
* Remove a buffer from its current buffer list in preparation for
* dropping it from its current transaction entirely. If the buffer has
* already started to be used by a subsequent transaction, refile the
*/
was_dirty = test_clear_buffer_jbddirty(bh);
- __journal_unfile_buffer(jh);
+ __journal_temp_unlink_buffer(jh);
jh->b_transaction = jh->b_next_transaction;
jh->b_next_transaction = NULL;
- __journal_file_buffer(jh, jh->b_transaction, BJ_Metadata);
+ __journal_file_buffer(jh, jh->b_transaction,
+ was_dirty ? BJ_Metadata : BJ_Reserved);
J_ASSERT_JH(jh, jh->b_transaction->t_state == T_RUNNING);
if (was_dirty)
* to the caller to remove the journal_head if necessary. For the
* unlocked journal_refile_buffer call, the caller isn't going to be
* doing anything else to the buffer so we need to do the cleanup
- * ourselves to avoid a jh leak.
+ * ourselves to avoid a jh leak.
*
* *** The journal_head may be freed by this call! ***
*/
git://git.onelab.eu / linux-2.6.git / blobdiff