[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/jffs2/background.c b/ap/os/linux/linux-3.4.x/fs/jffs2/background.c
new file mode 100644
index 0000000..2e546e1
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/jffs2/background.c
@@ -0,0 +1,312 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright © 2001-2007 Red Hat, Inc.
+ * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
+ *
+ * Created by David Woodhouse <dwmw2@infradead.org>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/jffs2.h>
+#include <linux/mtd/mtd.h>
+#include <linux/completion.h>
+#include <linux/sched.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include <linux/syscalls.h>
+#include "nodelist.h"
+
+/* quick gc wait timeout 60 seconds*/
+#define QUICK_GC_TIMEOUT_MS  60000
+
+struct jffs2_quick_gc_manager {
+	char * name;
+	struct jffs2_sb_info *c;
+	struct completion  *waiting;
+	 struct semaphore wait_sem;
+};
+
+static struct jffs2_quick_gc_manager jffs2_quick_gc_mtd[] = { 
+                                                  {"imagefs", NULL, NULL}, 
+                                                  {"resource", NULL, NULL},
+                                                  {"nvrofs", NULL, NULL}
+                                                };
+
+
+static struct jffs2_quick_gc_manager * jffs2_quick_gc_find_manager(const char *mtd_name)
+{
+	int i;
+	struct jffs2_quick_gc_manager *m = NULL;
+
+	for(i=0; i<sizeof(jffs2_quick_gc_mtd)/sizeof(jffs2_quick_gc_mtd[0]); i++) {
+		if(strcmp(mtd_name, jffs2_quick_gc_mtd[i].name) == 0)
+			m = &jffs2_quick_gc_mtd[i];
+	}
+
+	return m;
+}
+
+static int jffs2_quick_gc_clean_manager(struct jffs2_sb_info *c)
+{
+	int i;
+
+	for(i=0; i<sizeof(jffs2_quick_gc_mtd)/sizeof(jffs2_quick_gc_mtd[0]); i++) {
+		if(strcmp(c->mtd->name, jffs2_quick_gc_mtd[i].name) == 0)
+			jffs2_quick_gc_mtd[i].c = NULL;
+	}
+
+	return 0;
+}
+
+int quick_gc_wait_done(const char *mtd_name)
+{
+	struct jffs2_sb_info *c = NULL;
+	struct jffs2_quick_gc_manager *m = NULL;
+	struct completion waiting_done;
+
+	m = jffs2_quick_gc_find_manager(mtd_name);
+	BUG_ON(!m);
+
+	c = m->c;
+	if(c == NULL)
+		return 1; /*partition not exist or not rw mode*/
+	if(!c->gc_task)
+		return 1; /*no gc_task, not  rw mode*/
+	BUG_ON(m->waiting); /*must no waiting*/
+
+	down(&(m->wait_sem));
+	spin_lock(&c->erase_completion_lock);
+	if(jffs2_thread_should_wake(c)) {
+		m->waiting = &waiting_done;
+		init_completion(m->waiting);
+		printk(KERN_ALERT "[zgp] %s quick gc waiting start\n", c->mtd->name);
+		jffs2_quick_garbage_collect_trigger(c);
+		spin_unlock(&c->erase_completion_lock);
+		wait_for_completion_timeout(m->waiting, msecs_to_jiffies(QUICK_GC_TIMEOUT_MS));
+		m->waiting = NULL;
+		printk(KERN_ALERT "[zgp] %s quick gc waiting return\n", c->mtd->name);
+		up(&(m->wait_sem));
+		return 1;
+	}
+	spin_unlock(&c->erase_completion_lock);
+	up(&(m->wait_sem));
+
+	return 1;
+}
+
+SYSCALL_DEFINE1(jffs2_quick_gc_wait_done, int __user, partition_no)
+{
+	BUG_ON(partition_no >= sizeof(jffs2_quick_gc_mtd)/sizeof(jffs2_quick_gc_mtd[0]));
+
+	//printk(KERN_ALERT "[zgp]syscall %s wait done GC\n ", jffs2_quick_gc_mtd[partition_no].name);
+
+	return quick_gc_wait_done(jffs2_quick_gc_mtd[partition_no].name);
+}
+
+void jffs2_quick_gc_done(struct jffs2_sb_info *c)
+{
+	struct jffs2_quick_gc_manager *m = NULL;
+
+	assert_spin_locked(&c->erase_completion_lock);
+
+	m = jffs2_quick_gc_find_manager(c->mtd->name);
+	BUG_ON(!m);
+
+	if(m->waiting) {
+		//printk(KERN_ALERT "[zgp] mtd %s quck gc done\n", c->mtd->name);
+		complete(m->waiting);
+	}
+}
+
+static int jffs2_garbage_collect_thread(void *);
+
+void jffs2_garbage_collect_trigger(struct jffs2_sb_info *c)
+{
+	assert_spin_locked(&c->erase_completion_lock);
+	if (c->gc_task && jffs2_thread_should_wake(c)) {
+		//c->quick_gcblock_count = 0;
+		send_sig(SIGHUP, c->gc_task, 1);
+	}
+}
+
+/* add quick garbage collect trigger zgp*/
+void jffs2_quick_garbage_collect_trigger(struct jffs2_sb_info *c)
+{
+	assert_spin_locked(&c->erase_completion_lock);
+	if (c->gc_task) {
+		c->quick_wait = 1;
+		c->quick_gcblock_count = 0;
+		send_sig(SIGHUP, c->gc_task, 1);
+	}
+}
+
+/* This must only ever be called when no GC thread is currently running */
+int jffs2_start_garbage_collect_thread(struct jffs2_sb_info *c)
+{
+	struct task_struct *tsk;
+	int ret = 0;
+
+	BUG_ON(c->gc_task);
+
+	init_completion(&c->gc_thread_start);
+	init_completion(&c->gc_thread_exit);
+
+	for(ret = 0; ret < sizeof(jffs2_quick_gc_mtd)/sizeof(jffs2_quick_gc_mtd[0]); ret++) {
+		if(strcmp(c->mtd->name, jffs2_quick_gc_mtd[ret].name) == 0) {
+			c->flags |= JFFS2_SB_FLAG_QUICK_GC;
+			c->quick_gcblock_count = 0;
+			c->quick_wait = 0;
+			jffs2_quick_gc_mtd[ret].c = c;
+			sema_init(&(jffs2_quick_gc_mtd[ret].wait_sem), 1);
+			//printk(KERN_ALERT "[zgp]partition %s enable quick GC\n ", c->mtd->name);
+		}
+	}
+
+	tsk = kthread_run(jffs2_garbage_collect_thread, c, "jffs2_gcd_mtd%d", c->mtd->index);
+	if (IS_ERR(tsk)) {
+		pr_warn("fork failed for JFFS2 garbage collect thread: %ld\n",
+			-PTR_ERR(tsk));
+		complete(&c->gc_thread_exit);
+		ret = PTR_ERR(tsk);
+	} else {
+		/* Wait for it... */
+		jffs2_dbg(1, "Garbage collect thread is pid %d\n", tsk->pid);
+		wait_for_completion(&c->gc_thread_start);
+		ret = tsk->pid;
+	}
+
+	return ret;
+}
+
+void jffs2_stop_garbage_collect_thread(struct jffs2_sb_info *c)
+{
+	int wait = 0;
+	struct jffs2_quick_gc_manager *m = NULL;
+
+	if(c->flags & JFFS2_SB_FLAG_QUICK_GC) {
+		m = jffs2_quick_gc_find_manager(c->mtd->name);
+		BUG_ON(!m);
+		BUG_ON(m->waiting); /*some one wait for GC*/
+	}
+
+	spin_lock(&c->erase_completion_lock);
+	if (c->gc_task) {
+		jffs2_dbg(1, "Killing GC task %d\n", c->gc_task->pid);
+		send_sig(SIGKILL, c->gc_task, 1);
+		wait = 1;
+	}
+	spin_unlock(&c->erase_completion_lock);
+	if (wait)
+		wait_for_completion(&c->gc_thread_exit);
+
+	if(c->flags & JFFS2_SB_FLAG_QUICK_GC)
+		jffs2_quick_gc_clean_manager(c);
+
+}
+
+static int jffs2_garbage_collect_thread(void *_c)
+{
+	struct jffs2_sb_info *c = _c;
+
+	allow_signal(SIGKILL);
+	allow_signal(SIGSTOP);
+	allow_signal(SIGCONT);
+
+	c->gc_task = current;
+	complete(&c->gc_thread_start);
+
+	set_user_nice(current, 10);
+
+	set_freezable();
+	for (;;) {
+		allow_signal(SIGHUP);
+	again:
+		spin_lock(&c->erase_completion_lock);
+		if (!jffs2_thread_should_wake(c)) {
+			set_current_state (TASK_INTERRUPTIBLE);
+			if (c->flags & JFFS2_SB_FLAG_QUICK_GC) {
+				printk(KERN_ALERT "[zgp] mtd %s quck gc done and sleep,gcblock_cnt:%d\n", c->mtd->name, c->quick_gcblock_count);
+				jffs2_quick_gc_done(c);
+			}
+			spin_unlock(&c->erase_completion_lock);
+			jffs2_dbg(1, "%s(): sleeping...\n", __func__);
+			schedule();
+		} else
+			spin_unlock(&c->erase_completion_lock);
+			
+
+		/* Problem - immediately after bootup, the GCD spends a lot
+		 * of time in places like jffs2_kill_fragtree(); so much so
+		 * that userspace processes (like gdm and X) are starved
+		 * despite plenty of cond_resched()s and renicing.  Yield()
+		 * doesn't help, either (presumably because userspace and GCD
+		 * are generally competing for a higher latency resource -
+		 * disk).
+		 * This forces the GCD to slow the hell down.   Pulling an
+		 * inode in with read_inode() is much preferable to having
+		 * the GC thread get there first. */
+		if (c->flags & JFFS2_SB_FLAG_QUICK_GC) {
+			if(c->quick_wait != 2)
+				schedule_timeout_interruptible(msecs_to_jiffies(10));
+		} else
+			schedule_timeout_interruptible(msecs_to_jiffies(50));
+
+		if (kthread_should_stop()) {
+			jffs2_dbg(1, "%s(): kthread_stop() called\n", __func__);
+			goto die;
+		}
+
+		/* Put_super will send a SIGKILL and then wait on the sem.
+		 */
+		while (signal_pending(current) || freezing(current)) {
+			siginfo_t info;
+			unsigned long signr;
+
+			if (try_to_freeze())
+				goto again;
+
+			signr = dequeue_signal_lock(current, &current->blocked, &info);
+
+			switch(signr) {
+			case SIGSTOP:
+				jffs2_dbg(1, "%s(): SIGSTOP received\n",
+					  __func__);
+				set_current_state(TASK_STOPPED);
+				schedule();
+				break;
+
+			case SIGKILL:
+				jffs2_dbg(1, "%s(): SIGKILL received\n",
+					  __func__);
+				goto die;
+
+			case SIGHUP:
+				jffs2_dbg(1, "%s(): SIGHUP received\n",
+					  __func__);
+				break;
+			default:
+				jffs2_dbg(1, "%s(): signal %ld received\n",
+					  __func__, signr);
+			}
+		}
+		/* We don't want SIGHUP to interrupt us. STOP and KILL are OK though. */
+		disallow_signal(SIGHUP);
+
+		jffs2_dbg(1, "%s(): pass\n", __func__);
+		if (jffs2_garbage_collect_pass(c) == -ENOSPC) {
+			pr_notice("No space for garbage collection. Aborting GC thread\n");
+			goto die;
+		}
+	}
+ die:
+	spin_lock(&c->erase_completion_lock);
+	c->gc_task = NULL;
+	spin_unlock(&c->erase_completion_lock);
+	complete_and_exit(&c->gc_thread_exit, 0);
+}