[v4,6/6] btrfs: Enhance missing device kernel message

Commit Message

Qu Wenruo June 28, 2017, 5:43 a.m. UTC

For missing device, btrfs will just refuse to mount with almost
meaningless kernel message like:

 BTRFS info (device vdb6): disk space caching is enabled
 BTRFS info (device vdb6): has skinny extents
 BTRFS error (device vdb6): failed to read the system array: -5
 BTRFS error (device vdb6): open_ctree failed

This patch will add extra device missing output, making the result to:

 BTRFS info (device vdb6): disk space caching is enabled
 BTRFS info (device vdb6): has skinny extents
 BTRFS warning (device vdb6): devid 2 uuid 80470722-cad2-4b90-b7c3-fee294552f1b is missing
 BTRFS error (device vdb6): failed to read the system array: -5
 BTRFS error (device vdb6): open_ctree failed

Signed-off-by: Qu Wenruo <[e-mail]>
Reviewed-by: Anand Jain <[e-mail]>
---
 fs/btrfs/volumes.c | 24 +++++++++++++++++-------
 fs/btrfs/volumes.h |  2 ++
 2 files changed, 19 insertions(+), 7 deletions(-)

Patch

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 2cc68c74f701..a47e362de0eb 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6496,6 +6496,7 @@  static int read_one_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key,
 		if (!map->stripes[i].dev &&
 		    !btrfs_test_opt(fs_info, DEGRADED)) {
 			free_extent_map(em);
+			btrfs_report_missing_device(fs_info, devid, uuid);
 			return -EIO;
 		}
 		if (!map->stripes[i].dev) {
@@ -6506,8 +6507,7 @@  static int read_one_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key,
 				free_extent_map(em);
 				return -EIO;
 			}
-			btrfs_warn(fs_info, "devid %llu uuid %pU is missing",
-				   devid, uuid);
+			btrfs_report_missing_device(fs_info, devid, uuid);
 		}
 		map->stripes[i].dev->in_fs_metadata = 1;
 	}
@@ -6624,17 +6624,21 @@  static int read_one_dev(struct btrfs_fs_info *fs_info,
 
 	device = btrfs_find_device(fs_info, devid, dev_uuid, fs_uuid);
 	if (!device) {
-		if (!btrfs_test_opt(fs_info, DEGRADED))
+		if (!btrfs_test_opt(fs_info, DEGRADED)) {
+			btrfs_report_missing_device(fs_info, devid, dev_uuid);
 			return -EIO;
+		}
 
 		device = add_missing_dev(fs_devices, devid, dev_uuid);
 		if (!device)
 			return -ENOMEM;
-		btrfs_warn(fs_info, "devid %llu uuid %pU missing",
-				devid, dev_uuid);
+		btrfs_report_missing_device(fs_info, devid, dev_uuid);
 	} else {
-		if (!device->bdev && !btrfs_test_opt(fs_info, DEGRADED))
-			return -EIO;
+		if (!device->bdev) {
+			btrfs_report_missing_device(fs_info, devid, dev_uuid);
+			if (!btrfs_test_opt(fs_info, DEGRADED))
+				return -EIO;
+		}
 
 		if(!device->bdev && !device->missing) {
 			/*
@@ -6800,6 +6804,12 @@  int btrfs_read_sys_array(struct btrfs_fs_info *fs_info)
 	return -EIO;
 }
 
+void btrfs_report_missing_device(struct btrfs_fs_info *fs_info, u64 devid,
+				 u8 *uuid)
+{
+	btrfs_warn_rl(fs_info, "devid %llu uuid %pU is missing", devid, uuid);
+}
+
 /*
  * Check if all chunks in the fs is OK for read-write degraded mount
  *
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index a5897c7a7e86..9bd0447cffa8 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -544,4 +544,6 @@  void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
 
 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info);
+void btrfs_report_missing_device(struct btrfs_fs_info *fs_info, u64 devid,
+				 u8 *uuid);
 #endif