Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 165 insertions, 0 deletions

diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c
new file mode 100644
index 000000000..bb0ee1a59
--- /dev/null
+++ b/fs/jffs2/background.c
@@ -0,0 +1,165 @@
+/*
+ * 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/signal.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include "nodelist.h"
+
+
+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))
+		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);
+
+	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: %pe\n",
+			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;
+	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);
+}
+
+static int jffs2_garbage_collect_thread(void *_c)
+{
+	struct jffs2_sb_info *c = _c;
+	sigset_t hupmask;
+
+	siginitset(&hupmask, sigmask(SIGHUP));
+	allow_signal(SIGKILL);
+	allow_signal(SIGSTOP);
+	allow_signal(SIGHUP);
+
+	c->gc_task = current;
+	complete(&c->gc_thread_start);
+
+	set_user_nice(current, 10);
+
+	set_freezable();
+	for (;;) {
+		sigprocmask(SIG_UNBLOCK, &hupmask, NULL);
+	again:
+		spin_lock(&c->erase_completion_lock);
+		if (!jffs2_thread_should_wake(c)) {
+			set_current_state (TASK_INTERRUPTIBLE);
+			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. */
+		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)) {
+			unsigned long signr;
+
+			if (try_to_freeze())
+				goto again;
+
+			signr = kernel_dequeue_signal();
+
+			switch(signr) {
+			case SIGSTOP:
+				jffs2_dbg(1, "%s(): SIGSTOP received\n",
+					  __func__);
+				kernel_signal_stop();
+				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. */
+		sigprocmask(SIG_BLOCK, &hupmask, NULL);
+
+		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);
+	kthread_complete_and_exit(&c->gc_thread_exit, 0);
+}