1 files changed, 228 insertions, 91 deletions

diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 005b0375d18c..18ef069197e5 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -1,37 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 2007 Oracle.  All rights reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License v2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
  */
 
-#ifndef __BTRFS_TRANSACTION__
-#define __BTRFS_TRANSACTION__
+#ifndef BTRFS_TRANSACTION_H
+#define BTRFS_TRANSACTION_H
+
+#include <linux/atomic.h>
+#include <linux/refcount.h>
+#include <linux/list.h>
+#include <linux/time64.h>
+#include <linux/mutex.h>
+#include <linux/wait.h>
 #include "btrfs_inode.h"
 #include "delayed-ref.h"
-#include "ctree.h"
+
+struct dentry;
+struct inode;
+struct btrfs_pending_snapshot;
+struct btrfs_fs_info;
+struct btrfs_root_item;
+struct btrfs_root;
+struct btrfs_path;
+
+/*
+ * Signal that a direct IO write is in progress, to avoid deadlock for sync
+ * direct IO writes when fsync is called during the direct IO write path.
+ */
+#define BTRFS_TRANS_DIO_WRITE_STUB	((void *) 1)
+
+/* Radix-tree tag for roots that are part of the transaction. */
+#define BTRFS_ROOT_TRANS_TAG			0
 
 enum btrfs_trans_state {
-	TRANS_STATE_RUNNING		= 0,
-	TRANS_STATE_BLOCKED		= 1,
-	TRANS_STATE_COMMIT_START	= 2,
-	TRANS_STATE_COMMIT_DOING	= 3,
-	TRANS_STATE_UNBLOCKED		= 4,
-	TRANS_STATE_COMPLETED		= 5,
-	TRANS_STATE_MAX			= 6,
+	TRANS_STATE_RUNNING,
+	TRANS_STATE_COMMIT_PREP,
+	TRANS_STATE_COMMIT_START,
+	TRANS_STATE_COMMIT_DOING,
+	TRANS_STATE_UNBLOCKED,
+	TRANS_STATE_SUPER_COMMITTED,
+	TRANS_STATE_COMPLETED,
+	TRANS_STATE_MAX,
 };
 
+#define BTRFS_TRANS_HAVE_FREE_BGS	0
+#define BTRFS_TRANS_DIRTY_BG_RUN	1
+#define BTRFS_TRANS_CACHE_ENOSPC	2
+
 struct btrfs_transaction {
 	u64 transid;
 	/*
@@ -45,127 +60,249 @@ struct btrfs_transaction {
 	 * transaction can end
 	 */
 	atomic_t num_writers;
-	atomic_t use_count;
+	refcount_t use_count;
+
+	unsigned long flags;
 
 	/* Be protected by fs_info->trans_lock when we want to change it. */
 	enum btrfs_trans_state state;
+	int aborted;
 	struct list_head list;
 	struct extent_io_tree dirty_pages;
-	unsigned long start_time;
+	time64_t start_time;
 	wait_queue_head_t writer_wait;
 	wait_queue_head_t commit_wait;
 	struct list_head pending_snapshots;
-	struct list_head ordered_operations;
-	struct list_head pending_chunks;
+	struct list_head dev_update_list;
+	struct list_head switch_commits;
+	struct list_head dirty_bgs;
+
+	/*
+	 * There is no explicit lock which protects io_bgs, rather its
+	 * consistency is implied by the fact that all the sites which modify
+	 * it do so under some form of transaction critical section, namely:
+	 *
+	 * - btrfs_start_dirty_block_groups - This function can only ever be
+	 *   run by one of the transaction committers. Refer to
+	 *   BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction
+	 *
+	 * - btrfs_write_dirty_blockgroups - this is called by
+	 *   commit_cowonly_roots from transaction critical section
+	 *   (TRANS_STATE_COMMIT_DOING)
+	 *
+	 * - btrfs_cleanup_dirty_bgs - called on transaction abort
+	 */
+	struct list_head io_bgs;
+	struct list_head dropped_roots;
+	struct extent_io_tree pinned_extents;
+
+	/*
+	 * we need to make sure block group deletion doesn't race with
+	 * free space cache writeout.  This mutex keeps them from stomping
+	 * on each other
+	 */
+	struct mutex cache_write_mutex;
+	spinlock_t dirty_bgs_lock;
+	/* Protected by spin lock fs_info->unused_bgs_lock. */
+	struct list_head deleted_bgs;
+	spinlock_t dropped_roots_lock;
 	struct btrfs_delayed_ref_root delayed_refs;
-	int aborted;
-};
+	struct btrfs_fs_info *fs_info;
 
-#define __TRANS_FREEZABLE	(1U << 0)
+	/*
+	 * Number of ordered extents the transaction must wait for before
+	 * committing. These are ordered extents started by a fast fsync.
+	 */
+	atomic_t pending_ordered;
+	wait_queue_head_t pending_wait;
+};
 
-#define __TRANS_USERSPACE	(1U << 8)
-#define __TRANS_START		(1U << 9)
-#define __TRANS_ATTACH		(1U << 10)
-#define __TRANS_JOIN		(1U << 11)
-#define __TRANS_JOIN_NOLOCK	(1U << 12)
+enum {
+	ENUM_BIT(__TRANS_FREEZABLE),
+	ENUM_BIT(__TRANS_START),
+	ENUM_BIT(__TRANS_ATTACH),
+	ENUM_BIT(__TRANS_JOIN),
+	ENUM_BIT(__TRANS_JOIN_NOLOCK),
+	ENUM_BIT(__TRANS_DUMMY),
+	ENUM_BIT(__TRANS_JOIN_NOSTART),
+};
 
-#define TRANS_USERSPACE		(__TRANS_USERSPACE | __TRANS_FREEZABLE)
 #define TRANS_START		(__TRANS_START | __TRANS_FREEZABLE)
 #define TRANS_ATTACH		(__TRANS_ATTACH)
 #define TRANS_JOIN		(__TRANS_JOIN | __TRANS_FREEZABLE)
 #define TRANS_JOIN_NOLOCK	(__TRANS_JOIN_NOLOCK)
+#define TRANS_JOIN_NOSTART	(__TRANS_JOIN_NOSTART)
 
-#define TRANS_EXTWRITERS	(__TRANS_USERSPACE | __TRANS_START |	\
-				 __TRANS_ATTACH)
+#define TRANS_EXTWRITERS	(__TRANS_START | __TRANS_ATTACH)
 
 struct btrfs_trans_handle {
 	u64 transid;
 	u64 bytes_reserved;
-	u64 qgroup_reserved;
-	unsigned long use_count;
-	unsigned long blocks_reserved;
-	unsigned long blocks_used;
+	u64 delayed_refs_bytes_reserved;
+	u64 chunk_bytes_reserved;
 	unsigned long delayed_ref_updates;
+	unsigned long delayed_ref_csum_deletions;
 	struct btrfs_transaction *transaction;
 	struct btrfs_block_rsv *block_rsv;
 	struct btrfs_block_rsv *orig_rsv;
-	short aborted;
-	short adding_csums;
-	bool allocating_chunk;
+	/* Set by a task that wants to create a snapshot. */
+	struct btrfs_pending_snapshot *pending_snapshot;
+	refcount_t use_count;
 	unsigned int type;
 	/*
-	 * this root is only needed to validate that the root passed to
-	 * start_transaction is the same as the one passed to end_transaction.
-	 * Subvolume quota depends on this
+	 * Error code of transaction abort, set outside of locks and must use
+	 * the READ_ONCE/WRITE_ONCE access
 	 */
-	struct btrfs_root *root;
-	struct seq_list delayed_ref_elem;
-	struct list_head qgroup_ref_list;
+	short aborted;
+	bool adding_csums;
+	bool allocating_chunk;
+	bool removing_chunk;
+	bool reloc_reserved;
+	bool in_fsync;
+	struct btrfs_fs_info *fs_info;
 	struct list_head new_bgs;
+	struct btrfs_block_rsv delayed_rsv;
 };
 
+/*
+ * The abort status can be changed between calls and is not protected by locks.
+ * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's
+ * set to a non-zero value it does not change, so the macro should be in checks
+ * but is not necessary for further reads of the value.
+ */
+#define TRANS_ABORTED(trans)		(unlikely(READ_ONCE((trans)->aborted)))
+
 struct btrfs_pending_snapshot {
 	struct dentry *dentry;
-	struct inode *dir;
+	struct btrfs_inode *dir;
 	struct btrfs_root *root;
+	struct btrfs_root_item *root_item;
 	struct btrfs_root *snap;
 	struct btrfs_qgroup_inherit *inherit;
+	struct btrfs_path *path;
 	/* block reservation for the operation */
 	struct btrfs_block_rsv block_rsv;
-	u64 qgroup_reserved;
-	/* extra metadata reseration for relocation */
+	/* extra metadata reservation for relocation */
 	int error;
+	/* Preallocated anonymous block device number */
+	dev_t anon_dev;
 	bool readonly;
 	struct list_head list;
 };
 
 static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
-					      struct inode *inode)
+					      struct btrfs_inode *inode)
+{
+	spin_lock(&inode->lock);
+	inode->last_trans = trans->transaction->transid;
+	inode->last_sub_trans = btrfs_get_root_log_transid(inode->root);
+	inode->last_log_commit = inode->last_sub_trans - 1;
+	spin_unlock(&inode->lock);
+}
+
+/*
+ * Make qgroup codes to skip given qgroupid, means the old/new_roots for
+ * qgroup won't contain the qgroupid in it.
+ */
+static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,
+					 u64 qgroupid)
+{
+	struct btrfs_delayed_ref_root *delayed_refs;
+
+	delayed_refs = &trans->transaction->delayed_refs;
+	WARN_ON(delayed_refs->qgroup_to_skip);
+	delayed_refs->qgroup_to_skip = qgroupid;
+}
+
+static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)
+{
+	struct btrfs_delayed_ref_root *delayed_refs;
+
+	delayed_refs = &trans->transaction->delayed_refs;
+	WARN_ON(!delayed_refs->qgroup_to_skip);
+	delayed_refs->qgroup_to_skip = 0;
+}
+
+/*
+ * We want the transaction abort to print stack trace only for errors where the
+ * cause could be a bug, eg. due to ENOSPC, and not for common errors that are
+ * caused by external factors.
+ */
+static inline bool btrfs_abort_should_print_stack(int error)
 {
-	BTRFS_I(inode)->last_trans = trans->transaction->transid;
-	BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
-	BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
+	switch (error) {
+	case -EIO:
+	case -EROFS:
+	case -ENOMEM:
+		return false;
+	}
+	return true;
 }
 
-int btrfs_end_transaction(struct btrfs_trans_handle *trans,
-			  struct btrfs_root *root);
+/*
+ * Call btrfs_abort_transaction as early as possible when an error condition is
+ * detected, that way the exact stack trace is reported for some errors.
+ */
+#define btrfs_abort_transaction(trans, error)		\
+do {								\
+	bool __first = false;					\
+	/* Report first abort since mount */			\
+	if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED,	\
+			&((trans)->fs_info->fs_state))) {	\
+		__first = true;					\
+		if (WARN(btrfs_abort_should_print_stack(error),	\
+			KERN_ERR				\
+			"BTRFS: Transaction aborted (error %d)\n",	\
+			(error))) {					\
+			/* Stack trace printed. */			\
+		} else {						\
+			btrfs_err((trans)->fs_info,			\
+				  "Transaction aborted (error %d)",	\
+				  (error));			\
+		}						\
+	}							\
+	__btrfs_abort_transaction((trans), __func__,		\
+				  __LINE__, (error), __first);	\
+} while (0)
+
+int btrfs_end_transaction(struct btrfs_trans_handle *trans);
 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
-						   int num_items);
-struct btrfs_trans_handle *btrfs_start_transaction_lflush(
-					struct btrfs_root *root, int num_items);
+						   unsigned int num_items);
+struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
+					struct btrfs_root *root,
+					unsigned int num_items);
 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
-struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);
+struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root);
+struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
 					struct btrfs_root *root);
-struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root);
-int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid);
-int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
-				     struct btrfs_root *root);
-
-int btrfs_add_dead_root(struct btrfs_root *root);
-int btrfs_defrag_root(struct btrfs_root *root);
-int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
-int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
-			     struct btrfs_root *root);
-int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
-				   struct btrfs_root *root,
-				   int wait_for_unblock);
-int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans,
-				   struct btrfs_root *root);
-int btrfs_end_transaction_dmeta(struct btrfs_trans_handle *trans,
-				struct btrfs_root *root);
-int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root);
-void btrfs_throttle(struct btrfs_root *root);
+int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
+
+void btrfs_add_dead_root(struct btrfs_root *root);
+void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info);
+int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info *fs_info);
+int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
+void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans);
+int btrfs_commit_current_transaction(struct btrfs_root *root);
+int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans);
+bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans);
+void btrfs_throttle(struct btrfs_fs_info *fs_info);
 int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root);
-int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
-				struct extent_io_tree *dirty_pages, int mark);
-int btrfs_write_marked_extents(struct btrfs_root *root,
-				struct extent_io_tree *dirty_pages, int mark);
-int btrfs_wait_marked_extents(struct btrfs_root *root,
+int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
 				struct extent_io_tree *dirty_pages, int mark);
+int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark);
 int btrfs_transaction_blocked(struct btrfs_fs_info *info);
-int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
+void btrfs_put_transaction(struct btrfs_transaction *transaction);
+void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
+			    struct btrfs_root *root);
+void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans);
+void __cold __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
+				      const char *function,
+				      unsigned int line, int error, bool first_hit);
+
+int __init btrfs_transaction_init(void);
+void __cold btrfs_transaction_exit(void);
+
 #endif