[PATCH 03/12] Get rid of pdflush_operation() in emergency sync and remount

[Jens Axboe <jens.axboe@oracle.com>]

Opencode a cheasy approach with kevent. The idea here is that we'll
add some generic delayed work infrastructure, which probably wont be
based on pdflush (or maybe it will, in which case we can just add it
back).

This is in preparation for getting rid of pdflush completely.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 fs/super.c |   11 +++++++++--
 fs/sync.c  |   14 +++++++++++++-
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/fs/super.c b/fs/super.c
index 6ce5014..dd4acb1 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -674,7 +674,7 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
 	return 0;
 }
 
-static void do_emergency_remount(unsigned long foo)
+static void do_emergency_remount(struct work_struct *work)
 {
 	struct super_block *sb;
 
@@ -697,12 +697,19 @@ static void do_emergency_remount(unsigned long foo)
 		spin_lock(&sb_lock);
 	}
 	spin_unlock(&sb_lock);
+	kfree(work);
 	printk("Emergency Remount complete\n");
 }
 
 void emergency_remount(void)
 {
-	pdflush_operation(do_emergency_remount, 0);
+	struct work_struct *work;
+
+	work = kmalloc(sizeof(*work), GFP_ATOMIC);
+	if (work) {
+		INIT_WORK(work, do_emergency_remount);
+		schedule_work(work);
+	}
 }
 
 /*
diff --git a/fs/sync.c b/fs/sync.c
index a16d53e..ec95a69 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -42,9 +42,21 @@ SYSCALL_DEFINE0(sync)
 	return 0;
 }
 
+static void do_sync_work(struct work_struct *work)
+{
+	do_sync(0);
+	kfree(work);
+}
+
 void emergency_sync(void)
 {
-	pdflush_operation(do_sync, 0);
+	struct work_struct *work;
+
+	work = kmalloc(sizeof(*work), GFP_ATOMIC);
+	if (work) {
+		INIT_WORK(work, do_sync_work);
+		schedule_work(work);
+	}
 }
 
 /*
-- 
1.6.2.12.g83676