btrfs: refactor btrfs_dev_replace_start for reuse

A refactor patch, and avoids user input verification in the
btrfs_dev_replace_start(), and so this function can be reused.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 1a3d245..5aebedf 100644 (file)
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -302,8 +302,8 @@ void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info)
                dev_replace->cursor_left_last_write_of_item;
 }
 
-int btrfs_dev_replace_start(struct btrfs_root *root,
-                           struct btrfs_ioctl_dev_replace_args *args)
+int btrfs_dev_replace_start(struct btrfs_root *root, char *tgtdev_name,
+                               u64 srcdevid, char *srcdev_name, int read_src)
 {
        struct btrfs_trans_handle *trans;
        struct btrfs_fs_info *fs_info = root->fs_info;
@@ -312,25 +312,16 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
        struct btrfs_device *tgt_device = NULL;
        struct btrfs_device *src_device = NULL;
 
-       switch (args->start.cont_reading_from_srcdev_mode) {
-       case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS:
-       case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID:
-               break;
-       default:
-               return -EINVAL;
-       }
-
        /* the disk copy procedure reuses the scrub code */
        mutex_lock(&fs_info->volume_mutex);
-       ret = btrfs_find_device_by_devspec(root, args->start.srcdevid,
-                                           args->start.srcdev_name,
-                                           &src_device);
+       ret = btrfs_find_device_by_devspec(root, srcdevid,
+                                           srcdev_name, &src_device);
        if (ret) {
                mutex_unlock(&fs_info->volume_mutex);
                return ret;
        }
 
-       ret = btrfs_init_dev_replace_tgtdev(root, args->start.tgtdev_name,
+       ret = btrfs_init_dev_replace_tgtdev(root, tgtdev_name,
                                            src_device, &tgt_device);
        mutex_unlock(&fs_info->volume_mutex);
        if (ret)
@@ -357,12 +348,11 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
                break;
        case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
        case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
-               args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
+               ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
                goto leave;
        }
 
-       dev_replace->cont_reading_from_srcdev_mode =
-               args->start.cont_reading_from_srcdev_mode;
+       dev_replace->cont_reading_from_srcdev_mode = read_src;
        WARN_ON(!src_device);
        dev_replace->srcdev = src_device;
        WARN_ON(!tgt_device);
@@ -389,7 +379,6 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
        dev_replace->item_needs_writeback = 1;
        atomic64_set(&dev_replace->num_write_errors, 0);
        atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0);
-       args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
        btrfs_dev_replace_unlock(dev_replace, 1);
 
        ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device);
@@ -415,10 +404,8 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
                              &dev_replace->scrub_progress, 0, 1);
 
        ret = btrfs_dev_replace_finishing(fs_info, ret);
-       /* don't warn if EINPROGRESS, someone else might be running scrub */
        if (ret == -EINPROGRESS) {
-               args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS;
-               ret = 0;
+               ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS;
        } else {
                WARN_ON(ret);
        }
@@ -433,6 +420,35 @@ leave:
        return ret;
 }
 
+int btrfs_dev_replace_by_ioctl(struct btrfs_root *root,
+                           struct btrfs_ioctl_dev_replace_args *args)
+{
+       int ret;
+
+       switch (args->start.cont_reading_from_srcdev_mode) {
+       case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS:
+       case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID:
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') ||
+           args->start.tgtdev_name[0] == '\0')
+               return -EINVAL;
+
+       ret = btrfs_dev_replace_start(root, args->start.tgtdev_name,
+                                       args->start.srcdevid,
+                                       args->start.srcdev_name,
+                                       args->start.cont_reading_from_srcdev_mode);
+       args->result = ret;
+       /* don't warn if EINPROGRESS, someone else might be running scrub */
+       if (ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS)
+               ret = 0;
+
+       return ret;
+}
+
 /*
  * blocked until all flighting bios are finished.
  */

diff --git a/fs/btrfs/dev-replace.h b/fs/btrfs/dev-replace.h
index 29e3ef5..e922b42 100644 (file)
--- a/fs/btrfs/dev-replace.h
+++ b/fs/btrfs/dev-replace.h
@@ -25,8 +25,10 @@ int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info);
 int btrfs_run_dev_replace(struct btrfs_trans_handle *trans,
                          struct btrfs_fs_info *fs_info);
 void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info);
-int btrfs_dev_replace_start(struct btrfs_root *root,
+int btrfs_dev_replace_by_ioctl(struct btrfs_root *root,
                            struct btrfs_ioctl_dev_replace_args *args);
+int btrfs_dev_replace_start(struct btrfs_root *root, char *tgtdev_name,
+                               u64 srcdevid, char *srcdev_name, int read_src);
 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
                              struct btrfs_ioctl_dev_replace_args *args);
 int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info,

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 65903ec..36b1ed2 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4430,7 +4430,7 @@ static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
                        1)) {
                        ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
                } else {
-                       ret = btrfs_dev_replace_start(root, p);
+                       ret = btrfs_dev_replace_by_ioctl(root, p);
                        atomic_set(
                         &root->fs_info->mutually_exclusive_operation_running,
                         0);