Update Linux to v5.4.148
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz
Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c
index ee6f605..2656dc8 100644
--- a/fs/btrfs/reada.c
+++ b/fs/btrfs/reada.c
@@ -421,6 +421,9 @@
if (!dev->bdev)
continue;
+ if (test_bit(BTRFS_DEV_STATE_NO_READA, &dev->dev_state))
+ continue;
+
if (dev_replace_is_ongoing &&
dev == fs_info->dev_replace.tgtdev) {
/*
@@ -445,6 +448,8 @@
}
have_zone = 1;
}
+ if (!have_zone)
+ radix_tree_delete(&fs_info->reada_tree, index);
spin_unlock(&fs_info->reada_lock);
up_read(&fs_info->dev_replace.rwsem);
@@ -752,21 +757,19 @@
static void reada_start_machine_worker(struct btrfs_work *work)
{
struct reada_machine_work *rmw;
- struct btrfs_fs_info *fs_info;
int old_ioprio;
rmw = container_of(work, struct reada_machine_work, work);
- fs_info = rmw->fs_info;
-
- kfree(rmw);
old_ioprio = IOPRIO_PRIO_VALUE(task_nice_ioclass(current),
task_nice_ioprio(current));
set_task_ioprio(current, BTRFS_IOPRIO_READA);
- __reada_start_machine(fs_info);
+ __reada_start_machine(rmw->fs_info);
set_task_ioprio(current, old_ioprio);
- atomic_dec(&fs_info->reada_works_cnt);
+ atomic_dec(&rmw->fs_info->reada_works_cnt);
+
+ kfree(rmw);
}
static void __reada_start_machine(struct btrfs_fs_info *fs_info)
@@ -821,8 +824,7 @@
/* FIXME we cannot handle this properly right now */
BUG();
}
- btrfs_init_work(&rmw->work, btrfs_readahead_helper,
- reada_start_machine_worker, NULL, NULL);
+ btrfs_init_work(&rmw->work, reada_start_machine_worker, NULL, NULL);
rmw->fs_info = fs_info;
btrfs_queue_work(fs_info->readahead_workers, &rmw->work);
@@ -1015,3 +1017,45 @@
kref_put(&rc->refcnt, reada_control_release);
}
+
+/*
+ * Before removing a device (device replace or device remove ioctls), call this
+ * function to wait for all existing readahead requests on the device and to
+ * make sure no one queues more readahead requests for the device.
+ *
+ * Must be called without holding neither the device list mutex nor the device
+ * replace semaphore, otherwise it will deadlock.
+ */
+void btrfs_reada_remove_dev(struct btrfs_device *dev)
+{
+ struct btrfs_fs_info *fs_info = dev->fs_info;
+
+ /* Serialize with readahead extent creation at reada_find_extent(). */
+ spin_lock(&fs_info->reada_lock);
+ set_bit(BTRFS_DEV_STATE_NO_READA, &dev->dev_state);
+ spin_unlock(&fs_info->reada_lock);
+
+ /*
+ * There might be readahead requests added to the radix trees which
+ * were not yet added to the readahead work queue. We need to start
+ * them and wait for their completion, otherwise we can end up with
+ * use-after-free problems when dropping the last reference on the
+ * readahead extents and their zones, as they need to access the
+ * device structure.
+ */
+ reada_start_machine(fs_info);
+ btrfs_flush_workqueue(fs_info->readahead_workers);
+}
+
+/*
+ * If when removing a device (device replace or device remove ioctls) an error
+ * happens after calling btrfs_reada_remove_dev(), call this to undo what that
+ * function did. This is safe to call even if btrfs_reada_remove_dev() was not
+ * called before.
+ */
+void btrfs_reada_undo_remove_dev(struct btrfs_device *dev)
+{
+ spin_lock(&dev->fs_info->reada_lock);
+ clear_bit(BTRFS_DEV_STATE_NO_READA, &dev->dev_state);
+ spin_unlock(&dev->fs_info->reada_lock);
+}