1 files changed, 44 insertions, 36 deletions

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 5fe1ca8abc70..7c655f9a7a50 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -388,7 +388,7 @@ int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
         if (ret)
                 btrfs_err(fs_info, "kobj add dev failed %d", ret);
 
-        btrfs_wait_ordered_roots(fs_info, -1, 0, (u64)-1);
+        btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
 
         /* force writing the updated state information to disk */
         trans = btrfs_start_transaction(root, 0);
@@ -507,7 +507,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
                 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
                 return ret;
         }
-        btrfs_wait_ordered_roots(fs_info, -1, 0, (u64)-1);
+        btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
 
         trans = btrfs_start_transaction(root, 0);
         if (IS_ERR(trans)) {
@@ -639,11 +639,39 @@ static void btrfs_dev_replace_update_device_in_mapping_tree(
         write_unlock(&em_tree->lock);
 }
 
+/*
+ * Read progress of device replace status according to the state and last
+ * stored position. The value format is the same as for
+ * btrfs_dev_replace::progress_1000
+ */
+static u64 btrfs_dev_replace_progress(struct btrfs_fs_info *fs_info)
+{
+        struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
+        u64 ret = 0;
+
+        switch (dev_replace->replace_state) {
+        case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
+        case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
+                ret = 0;
+                break;
+        case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
+                ret = 1000;
+                break;
+        case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
+        case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
+                ret = div64_u64(dev_replace->cursor_left,
+                                div_u64(btrfs_device_get_total_bytes(
+                                                dev_replace->srcdev), 1000));
+                break;
+        }
+
+        return ret;
+}
+
 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
                               struct btrfs_ioctl_dev_replace_args *args)
 {
         struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
-        struct btrfs_device *srcdev;
 
         btrfs_dev_replace_lock(dev_replace, 0);
         /* even if !dev_replace_is_valid, the values are good enough for
@@ -656,21 +684,7 @@ void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
                 atomic64_read(&dev_replace->num_write_errors);
         args->status.num_uncorrectable_read_errors =
                 atomic64_read(&dev_replace->num_uncorrectable_read_errors);
-        switch (dev_replace->replace_state) {
-        case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
-        case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
-                args->status.progress_1000 = 0;
-                break;
-        case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
-                args->status.progress_1000 = 1000;
-                break;
-        case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
-        case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
-                srcdev = dev_replace->srcdev;
-                args->status.progress_1000 = div64_u64(dev_replace->cursor_left,
-                        div_u64(btrfs_device_get_total_bytes(srcdev), 1000));
-                break;
-        }
+        args->status.progress_1000 = btrfs_dev_replace_progress(fs_info);
         btrfs_dev_replace_unlock(dev_replace, 0);
 }
 
@@ -690,7 +704,7 @@ static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
         u64 result;
         int ret;
 
-        if (fs_info->sb->s_flags & MS_RDONLY)
+        if (sb_rdonly(fs_info->sb))
                 return -EROFS;
 
         mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
@@ -795,25 +809,19 @@ static int btrfs_dev_replace_kthread(void *data)
 {
         struct btrfs_fs_info *fs_info = data;
         struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
-        struct btrfs_ioctl_dev_replace_args *status_args;
         u64 progress;
 
-        status_args = kzalloc(sizeof(*status_args), GFP_KERNEL);
-        if (status_args) {
-                btrfs_dev_replace_status(fs_info, status_args);
-                progress = status_args->status.progress_1000;
-                kfree(status_args);
-                progress = div_u64(progress, 10);
-                btrfs_info_in_rcu(fs_info,
-                        "continuing dev_replace from %s (devid %llu) to %s @%u%%",
-                        dev_replace->srcdev->missing ? "<missing disk>" :
-                        rcu_str_deref(dev_replace->srcdev->name),
-                        dev_replace->srcdev->devid,
-                        dev_replace->tgtdev ?
-                        rcu_str_deref(dev_replace->tgtdev->name) :
-                        "<missing target disk>",
-                        (unsigned int)progress);
-        }
+        progress = btrfs_dev_replace_progress(fs_info);
+        progress = div_u64(progress, 10);
+        btrfs_info_in_rcu(fs_info,
+                "continuing dev_replace from %s (devid %llu) to %s @%u%%",
+                dev_replace->srcdev->missing ? "<missing disk>"
+                        : rcu_str_deref(dev_replace->srcdev->name),
+                dev_replace->srcdev->devid,
+                dev_replace->tgtdev ? rcu_str_deref(dev_replace->tgtdev->name)
+                        : "<missing target disk>",
+                (unsigned int)progress);
+
         btrfs_dev_replace_continue_on_mount(fs_info);
         clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);