[PATCH] Orphan patch using i_mutex and removing s_orphan_lock.

[T Makphaibulchoke]

Signed-off-by: T. Makphaibulchoke <tmac@xxxxxx>
---
 fs/ext4/ext4.h  |   4 +-
 fs/ext4/namei.c | 140 +++++++++++++++++++++++++++++++++++++-------------------
 fs/ext4/super.c |   4 +-
 3 files changed, 98 insertions(+), 50 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index d3a534f..5222a6b 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -77,6 +77,7 @@
 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
 
+#define	EXT4_ORPHAN_OP_BITS	7
 /* data type for block offset of block group */
 typedef int ext4_grpblk_t;
 
@@ -1223,7 +1224,8 @@ struct ext4_sb_info {
 	/* Journaling */
 	struct journal_s *s_journal;
 	struct list_head s_orphan;
-	struct mutex s_orphan_lock;
+	spinlock_t s_orphan_lock;
+	struct mutex s_ondisk_orphan_lock;
 	unsigned long s_resize_flags;		/* Flags indicating if there
 						   is a resizer */
 	unsigned long s_commit_interval;
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index d050e04..4a1a6a0 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2552,11 +2552,16 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode)
 	struct super_block *sb = inode->i_sb;
 	struct ext4_iloc iloc;
 	int err = 0, rc;
+	int lock_mutex = 0;
 
 	if (!EXT4_SB(sb)->s_journal)
 		return 0;
 
-	mutex_lock(&EXT4_SB(sb)->s_orphan_lock);
+	if (!mutex_is_locked(&inode->i_mutex)) {
+		lock_mutex = 1;
+		mutex_lock(&inode->i_mutex);
+	}
+
 	if (!list_empty(&EXT4_I(inode)->i_orphan))
 		goto out_unlock;
 
@@ -2582,9 +2587,23 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode)
 	 * orphan list. If so skip on-disk list modification.
 	 */
 	if (NEXT_ORPHAN(inode) && NEXT_ORPHAN(inode) <=
-		(le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count)))
-			goto mem_insert;
-
+		(le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))) {
+			brelse(iloc.bh);
+			mutex_lock(&EXT4_SB(sb)->s_ondisk_orphan_lock);
+			////spin_lock(&EXT4_SB(sb)->s_orphan_lock);
+			list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->
+				s_orphan);
+			mutex_unlock(&EXT4_SB(sb)->s_ondisk_orphan_lock);
+			////spin_unlock(&EXT4_SB(sb)->s_orphan_lock);
+			jbd_debug(4, "superblock will point to %lu\n",
+				inode->i_ino);
+			jbd_debug(4, "orphan inode %lu will point to %d\n",
+				inode->i_ino, NEXT_ORPHAN(inode));
+			goto out_unlock;
+	}
+
+	mutex_lock(&EXT4_SB(sb)->s_ondisk_orphan_lock);
+	//***spin_lock(&EXT4_SB(sb)->s_orphan_lock);
 	/* Insert this inode at the head of the on-disk orphan list... */
 	NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan);
 	EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
@@ -2592,24 +2611,28 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode)
 	rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
 	if (!err)
 		err = rc;
-
-	/* Only add to the head of the in-memory list if all the
-	 * previous operations succeeded.  If the orphan_add is going to
-	 * fail (possibly taking the journal offline), we can't risk
-	 * leaving the inode on the orphan list: stray orphan-list
-	 * entries can cause panics at unmount time.
-	 *
-	 * This is safe: on error we're going to ignore the orphan list
-	 * anyway on the next recovery. */
-mem_insert:
-	if (!err)
+	if (!err) {
+		/* Only add to the head of the in-memory list if all the
+		 * previous operations succeeded.  If the orphan_add is going to
+		 * fail (possibly taking the journal offline), we can't risk
+		 * leaving the inode on the orphan list: stray orphan-list
+		 * entries can cause panics at unmount time.
+		 *
+		 * This is safe: on error we're going to ignore the orphan list
+		 * anyway on the next recovery. */
 		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
-
-	jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
-	jbd_debug(4, "orphan inode %lu will point to %d\n",
+		//***spin_unlock(&EXT4_SB(sb)->s_orphan_lock);
+		jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
+		jbd_debug(4, "orphan inode %lu will point to %d\n",
 			inode->i_ino, NEXT_ORPHAN(inode));
+	}
+	//**else
+		//***spin_unlock(&EXT4_SB(sb)->s_orphan_lock);
+	mutex_unlock(&EXT4_SB(sb)->s_ondisk_orphan_lock);
+
 out_unlock:
-	mutex_unlock(&EXT4_SB(sb)->s_orphan_lock);
+	if (lock_mutex)
+		mutex_unlock(&inode->i_mutex);
 	ext4_std_error(inode->i_sb, err);
 	return err;
 }
@@ -2622,45 +2645,65 @@ int ext4_orphan_del(handle_t *handle, struct inode *inode)
 {
 	struct list_head *prev;
 	struct ext4_inode_info *ei = EXT4_I(inode);
-	struct ext4_sb_info *sbi;
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	__u32 ino_next;
 	struct ext4_iloc iloc;
 	int err = 0;
+	int lock_mutex = 0;
 
-	if ((!EXT4_SB(inode->i_sb)->s_journal) &&
-	    !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS))
+	if ((!sbi->s_journal) &&
+		!(sbi->s_mount_state & EXT4_ORPHAN_FS))
 		return 0;
 
-	mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
-	if (list_empty(&ei->i_orphan))
-		goto out;
-
-	ino_next = NEXT_ORPHAN(inode);
-	prev = ei->i_orphan.prev;
-	sbi = EXT4_SB(inode->i_sb);
+	if (!mutex_is_locked(&inode->i_mutex)) {
+		lock_mutex = 1;
+		mutex_lock(&inode->i_mutex);
+	}
 
-	jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
+	if (list_empty(&ei->i_orphan)) {
+		if (lock_mutex)
+			mutex_unlock(&inode->i_mutex);
+		return 0;
+	}
 
-	list_del_init(&ei->i_orphan);
 
 	/* If we're on an error path, we may not have a valid
 	 * transaction handle with which to update the orphan list on
 	 * disk, but we still need to remove the inode from the linked
 	 * list in memory. */
-	if (!handle)
-		goto out;
+	if (!handle) {
+		jbd_debug(4, "remove inode %lu from orphan list\n",
+			inode->i_ino);
+		mutex_lock(&sbi->s_ondisk_orphan_lock);
+		////spin_lock(&sbi->s_orphan_lock);
+		list_del_init(&ei->i_orphan);
+		mutex_unlock(&sbi->s_ondisk_orphan_lock);
+		////spin_unlock(&sbi->s_orphan_lock);
+	} else
+		err = ext4_reserve_inode_write(handle, inode, &iloc);
 
-	err = ext4_reserve_inode_write(handle, inode, &iloc);
-	if (err)
-		goto out_err;
+	if (!handle || err) {
+		if (lock_mutex)
+			mutex_unlock(&inode->i_mutex);
+		goto out_set_err;
+	}
 
+	mutex_lock(&sbi->s_ondisk_orphan_lock);
+	ino_next = NEXT_ORPHAN(inode);
+	//***spin_lock(&sbi->s_orphan_lock);
+	prev = ei->i_orphan.prev;
+	jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
+	list_del_init(&ei->i_orphan);
+	//***spin_unlock(&sbi->s_orphan_lock);
 	if (prev == &sbi->s_orphan) {
 		jbd_debug(4, "superblock will point to %u\n", ino_next);
 		BUFFER_TRACE(sbi->s_sbh, "get_write_access");
 		err = ext4_journal_get_write_access(handle, sbi->s_sbh);
+		if (!err)
+			sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
+		mutex_unlock(&sbi->s_ondisk_orphan_lock);
 		if (err)
-			goto out_brelse;
-		sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
+			goto brelse;
 		err = ext4_handle_dirty_super(handle, inode->i_sb);
 	} else {
 		struct ext4_iloc iloc2;
@@ -2670,25 +2713,28 @@ int ext4_orphan_del(handle_t *handle, struct inode *inode)
 		jbd_debug(4, "orphan inode %lu will point to %u\n",
 			  i_prev->i_ino, ino_next);
 		err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
+		if (!err)
+			NEXT_ORPHAN(i_prev) = ino_next;
+		mutex_unlock(&sbi->s_ondisk_orphan_lock);
 		if (err)
-			goto out_brelse;
-		NEXT_ORPHAN(i_prev) = ino_next;
+			goto brelse;
 		err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
 	}
 	if (err)
-		goto out_brelse;
+		goto brelse;
 	NEXT_ORPHAN(inode) = 0;
+	if (lock_mutex)
+		mutex_unlock(&inode->i_mutex);
 	err = ext4_mark_iloc_dirty(handle, inode, &iloc);
-
-out_err:
+out_set_err:
 	ext4_std_error(inode->i_sb, err);
-out:
-	mutex_unlock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
 	return err;
 
-out_brelse:
+brelse:
+	if (lock_mutex)
+		mutex_unlock(&inode->i_mutex);
 	brelse(iloc.bh);
-	goto out_err;
+	goto out_set_err;
 }
 
 static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 710fed2..ad9c45d 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3921,8 +3921,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
 
 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
-	mutex_init(&sbi->s_orphan_lock);
-
+	spin_lock_init(&sbi->s_orphan_lock);
+	mutex_init(&sbi->s_ondisk_orphan_lock);
 	sb->s_root = NULL;
 
 	needs_recovery = (es->s_last_orphan != 0 ||
-- 
1.7.11.3


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