1 files changed, 153 insertions, 127 deletions

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index e9a3c4c85594..02c7ad9d7a41 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -35,7 +35,6 @@
 #include <linux/kthread.h>
 #include <linux/poison.h>
 #include <linux/proc_fs.h>
-#include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/math64.h>
 #include <linux/hash.h>
@@ -51,6 +50,14 @@
 #include <asm/uaccess.h>
 #include <asm/page.h>
 
+#ifdef CONFIG_JBD2_DEBUG
+ushort jbd2_journal_enable_debug __read_mostly;
+EXPORT_SYMBOL(jbd2_journal_enable_debug);
+
+module_param_named(jbd2_debug, jbd2_journal_enable_debug, ushort, 0644);
+MODULE_PARM_DESC(jbd2_debug, "Debugging level for jbd2");
+#endif
+
 EXPORT_SYMBOL(jbd2_journal_extend);
 EXPORT_SYMBOL(jbd2_journal_stop);
 EXPORT_SYMBOL(jbd2_journal_lock_updates);
@@ -60,7 +67,6 @@ EXPORT_SYMBOL(jbd2_journal_get_create_access);
 EXPORT_SYMBOL(jbd2_journal_get_undo_access);
 EXPORT_SYMBOL(jbd2_journal_set_triggers);
 EXPORT_SYMBOL(jbd2_journal_dirty_metadata);
-EXPORT_SYMBOL(jbd2_journal_release_buffer);
 EXPORT_SYMBOL(jbd2_journal_forget);
 #if 0
 EXPORT_SYMBOL(journal_sync_buffer);
@@ -97,6 +103,24 @@ EXPORT_SYMBOL(jbd2_inode_cache);
 static void __journal_abort_soft (journal_t *journal, int errno);
 static int jbd2_journal_create_slab(size_t slab_size);
 
+#ifdef CONFIG_JBD2_DEBUG
+void __jbd2_debug(int level, const char *file, const char *func,
+		  unsigned int line, const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	if (level > jbd2_journal_enable_debug)
+		return;
+	va_start(args, fmt);
+	vaf.fmt = fmt;
+	vaf.va = &args;
+	printk(KERN_DEBUG "%s: (%s, %u): %pV\n", file, func, line, &vaf);
+	va_end(args);
+}
+EXPORT_SYMBOL(__jbd2_debug);
+#endif
+
 /* Checksumming functions */
 int jbd2_verify_csum_type(journal_t *j, journal_superblock_t *sb)
 {
@@ -304,14 +328,12 @@ static void journal_kill_thread(journal_t *journal)
  *
  * If the source buffer has already been modified by a new transaction
  * since we took the last commit snapshot, we use the frozen copy of
- * that data for IO.  If we end up using the existing buffer_head's data
- * for the write, then we *have* to lock the buffer to prevent anyone
- * else from using and possibly modifying it while the IO is in
- * progress.
- *
- * The function returns a pointer to the buffer_heads to be used for IO.
+ * that data for IO. If we end up using the existing buffer_head's data
+ * for the write, then we have to make sure nobody modifies it while the
+ * IO is in progress. do_get_write_access() handles this.
  *
- * We assume that the journal has already been locked in this function.
+ * The function returns a pointer to the buffer_head to be used for IO.
+ * 
  *
  * Return value:
  *  <0: Error
@@ -324,15 +346,14 @@ static void journal_kill_thread(journal_t *journal)
 
 int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
 				  struct journal_head  *jh_in,
-				  struct journal_head **jh_out,
-				  unsigned long long blocknr)
+				  struct buffer_head **bh_out,
+				  sector_t blocknr)
 {
 	int need_copy_out = 0;
 	int done_copy_out = 0;
 	int do_escape = 0;
 	char *mapped_data;
 	struct buffer_head *new_bh;
-	struct journal_head *new_jh;
 	struct page *new_page;
 	unsigned int new_offset;
 	struct buffer_head *bh_in = jh2bh(jh_in);
@@ -361,17 +382,14 @@ retry_alloc:
 	}
 
 	/* keep subsequent assertions sane */
-	new_bh->b_state = 0;
-	init_buffer(new_bh, NULL, NULL);
 	atomic_set(&new_bh->b_count, 1);
-	new_jh = jbd2_journal_add_journal_head(new_bh);	/* This sleeps */
 
+	jbd_lock_bh_state(bh_in);
+repeat:
 	/*
 	 * If a new transaction has already done a buffer copy-out, then
 	 * we use that version of the data for the commit.
 	 */
-	jbd_lock_bh_state(bh_in);
-repeat:
 	if (jh_in->b_frozen_data) {
 		done_copy_out = 1;
 		new_page = virt_to_page(jh_in->b_frozen_data);
@@ -411,7 +429,7 @@ repeat:
 		jbd_unlock_bh_state(bh_in);
 		tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS);
 		if (!tmp) {
-			jbd2_journal_put_journal_head(new_jh);
+			brelse(new_bh);
 			return -ENOMEM;
 		}
 		jbd_lock_bh_state(bh_in);
@@ -422,7 +440,7 @@ repeat:
 
 		jh_in->b_frozen_data = tmp;
 		mapped_data = kmap_atomic(new_page);
-		memcpy(tmp, mapped_data + new_offset, jh2bh(jh_in)->b_size);
+		memcpy(tmp, mapped_data + new_offset, bh_in->b_size);
 		kunmap_atomic(mapped_data);
 
 		new_page = virt_to_page(tmp);
@@ -448,14 +466,14 @@ repeat:
 	}
 
 	set_bh_page(new_bh, new_page, new_offset);
-	new_jh->b_transaction = NULL;
-	new_bh->b_size = jh2bh(jh_in)->b_size;
-	new_bh->b_bdev = transaction->t_journal->j_dev;
+	new_bh->b_size = bh_in->b_size;
+	new_bh->b_bdev = journal->j_dev;
 	new_bh->b_blocknr = blocknr;
+	new_bh->b_private = bh_in;
 	set_buffer_mapped(new_bh);
 	set_buffer_dirty(new_bh);
 
-	*jh_out = new_jh;
+	*bh_out = new_bh;
 
 	/*
 	 * The to-be-written buffer needs to get moved to the io queue,
@@ -466,11 +484,9 @@ repeat:
 	spin_lock(&journal->j_list_lock);
 	__jbd2_journal_file_buffer(jh_in, transaction, BJ_Shadow);
 	spin_unlock(&journal->j_list_lock);
+	set_buffer_shadow(bh_in);
 	jbd_unlock_bh_state(bh_in);
 
-	JBUFFER_TRACE(new_jh, "file as BJ_IO");
-	jbd2_journal_file_buffer(new_jh, transaction, BJ_IO);
-
 	return do_escape | (done_copy_out << 1);
 }
 
@@ -480,40 +496,15 @@ repeat:
  */
 
 /*
- * __jbd2_log_space_left: Return the number of free blocks left in the journal.
- *
- * Called with the journal already locked.
- *
- * Called under j_state_lock
- */
-
-int __jbd2_log_space_left(journal_t *journal)
-{
-	int left = journal->j_free;
-
-	/* assert_spin_locked(&journal->j_state_lock); */
-
-	/*
-	 * Be pessimistic here about the number of those free blocks which
-	 * might be required for log descriptor control blocks.
-	 */
-
-#define MIN_LOG_RESERVED_BLOCKS 32 /* Allow for rounding errors */
-
-	left -= MIN_LOG_RESERVED_BLOCKS;
-
-	if (left <= 0)
-		return 0;
-	left -= (left >> 3);
-	return left;
-}
-
-/*
  * Called with j_state_lock locked for writing.
  * Returns true if a transaction commit was started.
  */
 int __jbd2_log_start_commit(journal_t *journal, tid_t target)
 {
+	/* Return if the txn has already requested to be committed */
+	if (journal->j_commit_request == target)
+		return 0;
+
 	/*
 	 * The only transaction we can possibly wait upon is the
 	 * currently running transaction (if it exists).  Otherwise,
@@ -530,6 +521,7 @@ int __jbd2_log_start_commit(journal_t *journal, tid_t target)
 		jbd_debug(1, "JBD2: requesting commit %d/%d\n",
 			  journal->j_commit_request,
 			  journal->j_commit_sequence);
+		journal->j_running_transaction->t_requested = jiffies;
 		wake_up(&journal->j_wait_commit);
 		return 1;
 	} else if (!tid_geq(journal->j_commit_request, target))
@@ -555,20 +547,17 @@ int jbd2_log_start_commit(journal_t *journal, tid_t tid)
 }
 
 /*
- * Force and wait upon a commit if the calling process is not within
- * transaction.  This is used for forcing out undo-protected data which contains
- * bitmaps, when the fs is running out of space.
- *
- * We can only force the running transaction if we don't have an active handle;
- * otherwise, we will deadlock.
- *
- * Returns true if a transaction was started.
+ * Force and wait any uncommitted transactions.  We can only force the running
+ * transaction if we don't have an active handle, otherwise, we will deadlock.
+ * Returns: <0 in case of error,
+ *           0 if nothing to commit,
+ *           1 if transaction was successfully committed.
  */
-int jbd2_journal_force_commit_nested(journal_t *journal)
+static int __jbd2_journal_force_commit(journal_t *journal)
 {
 	transaction_t *transaction = NULL;
 	tid_t tid;
-	int need_to_start = 0;
+	int need_to_start = 0, ret = 0;
 
 	read_lock(&journal->j_state_lock);
 	if (journal->j_running_transaction && !current->journal_info) {
@@ -579,16 +568,53 @@ int jbd2_journal_force_commit_nested(journal_t *journal)
 		transaction = journal->j_committing_transaction;
 
 	if (!transaction) {
+		/* Nothing to commit */
 		read_unlock(&journal->j_state_lock);
-		return 0;	/* Nothing to retry */
+		return 0;
 	}
-
 	tid = transaction->t_tid;
 	read_unlock(&journal->j_state_lock);
 	if (need_to_start)
 		jbd2_log_start_commit(journal, tid);
-	jbd2_log_wait_commit(journal, tid);
-	return 1;
+	ret = jbd2_log_wait_commit(journal, tid);
+	if (!ret)
+		ret = 1;
+
+	return ret;
+}
+
+/**
+ * Force and wait upon a commit if the calling process is not within
+ * transaction.  This is used for forcing out undo-protected data which contains
+ * bitmaps, when the fs is running out of space.
+ *
+ * @journal: journal to force
+ * Returns true if progress was made.
+ */
+int jbd2_journal_force_commit_nested(journal_t *journal)
+{
+	int ret;
+
+	ret = __jbd2_journal_force_commit(journal);
+	return ret > 0;
+}
+
+/**
+ * int journal_force_commit() - force any uncommitted transactions
+ * @journal: journal to force
+ *
+ * Caller want unconditional commit. We can only force the running transaction
+ * if we don't have an active handle, otherwise, we will deadlock.
+ */
+int jbd2_journal_force_commit(journal_t *journal)
+{
+	int ret;
+
+	J_ASSERT(!current->journal_info);
+	ret = __jbd2_journal_force_commit(journal);
+	if (ret > 0)
+		ret = 0;
+	return ret;
 }
 
 /*
@@ -612,8 +638,8 @@ int jbd2_journal_start_commit(journal_t *journal, tid_t *ptid)
 		ret = 1;
 	} else if (journal->j_committing_transaction) {
 		/*
-		 * If ext3_write_super() recently started a commit, then we
-		 * have to wait for completion of that transaction
+		 * If commit has been started, then we have to wait for
+		 * completion of that transaction.
 		 */
 		if (ptid)
 			*ptid = journal->j_committing_transaction->t_tid;
@@ -699,6 +725,37 @@ int jbd2_log_wait_commit(journal_t *journal, tid_t tid)
 }
 
 /*
+ * When this function returns the transaction corresponding to tid
+ * will be completed.  If the transaction has currently running, start
+ * committing that transaction before waiting for it to complete.  If
+ * the transaction id is stale, it is by definition already completed,
+ * so just return SUCCESS.
+ */
+int jbd2_complete_transaction(journal_t *journal, tid_t tid)
+{
+	int	need_to_wait = 1;
+
+	read_lock(&journal->j_state_lock);
+	if (journal->j_running_transaction &&
+	    journal->j_running_transaction->t_tid == tid) {
+		if (journal->j_commit_request != tid) {
+			/* transaction not yet started, so request it */
+			read_unlock(&journal->j_state_lock);
+			jbd2_log_start_commit(journal, tid);
+			goto wait_commit;
+		}
+	} else if (!(journal->j_committing_transaction &&
+		     journal->j_committing_transaction->t_tid == tid))
+		need_to_wait = 0;
+	read_unlock(&journal->j_state_lock);
+	if (!need_to_wait)
+		return 0;
+wait_commit:
+	return jbd2_log_wait_commit(journal, tid);
+}
+EXPORT_SYMBOL(jbd2_complete_transaction);
+
+/*
  * Log buffer allocation routines:
  */
 
@@ -758,7 +815,7 @@ int jbd2_journal_bmap(journal_t *journal, unsigned long blocknr,
  * But we don't bother doing that, so there will be coherency problems with
  * mmaps of blockdevs which hold live JBD-controlled filesystems.
  */
-struct journal_head *jbd2_journal_get_descriptor_buffer(journal_t *journal)
+struct buffer_head *jbd2_journal_get_descriptor_buffer(journal_t *journal)
 {
 	struct buffer_head *bh;
 	unsigned long long blocknr;
@@ -777,7 +834,7 @@ struct journal_head *jbd2_journal_get_descriptor_buffer(journal_t *journal)
 	set_buffer_uptodate(bh);
 	unlock_buffer(bh);
 	BUFFER_TRACE(bh, "return this buffer");
-	return jbd2_journal_add_journal_head(bh);
+	return bh;
 }
 
 /*
@@ -895,13 +952,18 @@ static int jbd2_seq_info_show(struct seq_file *seq, void *v)
 
 	if (v != SEQ_START_TOKEN)
 		return 0;
-	seq_printf(seq, "%lu transaction, each up to %u blocks\n",
-			s->stats->ts_tid,
-			s->journal->j_max_transaction_buffers);
+	seq_printf(seq, "%lu transactions (%lu requested), "
+		   "each up to %u blocks\n",
+		   s->stats->ts_tid, s->stats->ts_requested,
+		   s->journal->j_max_transaction_buffers);
 	if (s->stats->ts_tid == 0)
 		return 0;
 	seq_printf(seq, "average: \n  %ums waiting for transaction\n",
 	    jiffies_to_msecs(s->stats->run.rs_wait / s->stats->ts_tid));
+	seq_printf(seq, "  %ums request delay\n",
+	    (s->stats->ts_requested == 0) ? 0 :
+	    jiffies_to_msecs(s->stats->run.rs_request_delay /
+			     s->stats->ts_requested));
 	seq_printf(seq, "  %ums running transaction\n",
 	    jiffies_to_msecs(s->stats->run.rs_running / s->stats->ts_tid));
 	seq_printf(seq, "  %ums transaction was being locked\n",
@@ -934,7 +996,7 @@ static const struct seq_operations jbd2_seq_info_ops = {
 
 static int jbd2_seq_info_open(struct inode *inode, struct file *file)
 {
-	journal_t *journal = PDE(inode)->data;
+	journal_t *journal = PDE_DATA(inode);
 	struct jbd2_stats_proc_session *s;
 	int rc, size;
 
@@ -1017,11 +1079,10 @@ static journal_t * journal_init_common (void)
 		return NULL;
 
 	init_waitqueue_head(&journal->j_wait_transaction_locked);
-	init_waitqueue_head(&journal->j_wait_logspace);
 	init_waitqueue_head(&journal->j_wait_done_commit);
-	init_waitqueue_head(&journal->j_wait_checkpoint);
 	init_waitqueue_head(&journal->j_wait_commit);
 	init_waitqueue_head(&journal->j_wait_updates);
+	init_waitqueue_head(&journal->j_wait_reserved);
 	mutex_init(&journal->j_barrier);
 	mutex_init(&journal->j_checkpoint_mutex);
 	spin_lock_init(&journal->j_revoke_lock);
@@ -1031,6 +1092,7 @@ static journal_t * journal_init_common (void)
 	journal->j_commit_interval = (HZ * JBD2_DEFAULT_MAX_COMMIT_AGE);
 	journal->j_min_batch_time = 0;
 	journal->j_max_batch_time = 15000; /* 15ms */
+	atomic_set(&journal->j_reserved_credits, 0);
 
 	/* The journal is marked for error until we succeed with recovery! */
 	journal->j_flags = JBD2_ABORT;
@@ -1273,6 +1335,7 @@ static int journal_reset(journal_t *journal)
 static void jbd2_write_superblock(journal_t *journal, int write_op)
 {
 	struct buffer_head *bh = journal->j_sb_buffer;
+	journal_superblock_t *sb = journal->j_superblock;
 	int ret;
 
 	trace_jbd2_write_superblock(journal, write_op);
@@ -1294,6 +1357,7 @@ static void jbd2_write_superblock(journal_t *journal, int write_op)
 		clear_buffer_write_io_error(bh);
 		set_buffer_uptodate(bh);
 	}
+	jbd2_superblock_csum_set(journal, sb);
 	get_bh(bh);
 	bh->b_end_io = end_buffer_write_sync;
 	ret = submit_bh(write_op, bh);
@@ -1354,6 +1418,11 @@ static void jbd2_mark_journal_empty(journal_t *journal)
 
 	BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex));
 	read_lock(&journal->j_state_lock);
+	/* Is it already empty? */
+	if (sb->s_start == 0) {
+		read_unlock(&journal->j_state_lock);
+		return;
+	}
 	jbd_debug(1, "JBD2: Marking journal as empty (seq %d)\n",
 		  journal->j_tail_sequence);
 
@@ -1377,7 +1446,7 @@ static void jbd2_mark_journal_empty(journal_t *journal)
  * Update a journal's errno.  Write updated superblock to disk waiting for IO
  * to complete.
  */
-static void jbd2_journal_update_sb_errno(journal_t *journal)
+void jbd2_journal_update_sb_errno(journal_t *journal)
 {
 	journal_superblock_t *sb = journal->j_superblock;
 
@@ -1385,11 +1454,11 @@ static void jbd2_journal_update_sb_errno(journal_t *journal)
 	jbd_debug(1, "JBD2: updating superblock error (errno %d)\n",
 		  journal->j_errno);
 	sb->s_errno    = cpu_to_be32(journal->j_errno);
-	jbd2_superblock_csum_set(journal, sb);
 	read_unlock(&journal->j_state_lock);
 
 	jbd2_write_superblock(journal, WRITE_SYNC);
 }
+EXPORT_SYMBOL(jbd2_journal_update_sb_errno);
 
 /*
  * Read the superblock for a given journal, performing initial
@@ -2274,13 +2343,13 @@ static struct journal_head *journal_alloc_journal_head(void)
 #ifdef CONFIG_JBD2_DEBUG
 	atomic_inc(&nr_journal_heads);
 #endif
-	ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS);
+	ret = kmem_cache_zalloc(jbd2_journal_head_cache, GFP_NOFS);
 	if (!ret) {
 		jbd_debug(1, "out of memory for journal_head\n");
 		pr_notice_ratelimited("ENOMEM in %s, retrying.\n", __func__);
 		while (!ret) {
 			yield();
-			ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS);
+			ret = kmem_cache_zalloc(jbd2_journal_head_cache, GFP_NOFS);
 		}
 	}
 	return ret;
@@ -2342,10 +2411,8 @@ struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh)
 	struct journal_head *new_jh = NULL;
 
 repeat:
-	if (!buffer_jbd(bh)) {
+	if (!buffer_jbd(bh))
 		new_jh = journal_alloc_journal_head();
-		memset(new_jh, 0, sizeof(*new_jh));
-	}
 
 	jbd_lock_bh_journal_head(bh);
 	if (buffer_jbd(bh)) {
@@ -2480,45 +2547,6 @@ restart:
 	spin_unlock(&journal->j_list_lock);
 }
 
-/*
- * debugfs tunables
- */
-#ifdef CONFIG_JBD2_DEBUG
-u8 jbd2_journal_enable_debug __read_mostly;
-EXPORT_SYMBOL(jbd2_journal_enable_debug);
-
-#define JBD2_DEBUG_NAME "jbd2-debug"
-
-static struct dentry *jbd2_debugfs_dir;
-static struct dentry *jbd2_debug;
-
-static void __init jbd2_create_debugfs_entry(void)
-{
-	jbd2_debugfs_dir = debugfs_create_dir("jbd2", NULL);
-	if (jbd2_debugfs_dir)
-		jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME,
-					       S_IRUGO | S_IWUSR,
-					       jbd2_debugfs_dir,
-					       &jbd2_journal_enable_debug);
-}
-
-static void __exit jbd2_remove_debugfs_entry(void)
-{
-	debugfs_remove(jbd2_debug);
-	debugfs_remove(jbd2_debugfs_dir);
-}
-
-#else
-
-static void __init jbd2_create_debugfs_entry(void)
-{
-}
-
-static void __exit jbd2_remove_debugfs_entry(void)
-{
-}
-
-#endif
 
 #ifdef CONFIG_PROC_FS
 
@@ -2604,7 +2632,6 @@ static int __init journal_init(void)
 
 	ret = journal_init_caches();
 	if (ret == 0) {
-		jbd2_create_debugfs_entry();
 		jbd2_create_jbd_stats_proc_entry();
 	} else {
 		jbd2_journal_destroy_caches();
@@ -2619,7 +2646,6 @@ static void __exit journal_exit(void)
 	if (n)
 		printk(KERN_EMERG "JBD2: leaked %d journal_heads!\n", n);
 #endif
-	jbd2_remove_debugfs_entry();
 	jbd2_remove_jbd_stats_proc_entry();
 	jbd2_journal_destroy_caches();
 }