ext4: add a mount opt to forcefully turn fast commits on

This is a debug only mount option that forcefully turns fast commits
on at mount time.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-9-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 9fcf1e3dfe764c8691eb07a3693657267e8b988d..5308f0d5fb5a5b3d56c3e304b8a5fba7ca65cdaf 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1719,8 +1719,9 @@ enum {
        Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
        Opt_prefetch_block_bitmaps, Opt_no_fc,
 #ifdef CONFIG_EXT4_DEBUG
-       Opt_fc_debug_max_replay
+       Opt_fc_debug_max_replay,
 #endif
+       Opt_fc_debug_force
 };
 
 static const match_table_t tokens = {
@@ -1808,6 +1809,7 @@ static const match_table_t tokens = {
        {Opt_init_itable, "init_itable"},
        {Opt_noinit_itable, "noinit_itable"},
        {Opt_no_fc, "no_fc"},
+       {Opt_fc_debug_force, "fc_debug_force"},
 #ifdef CONFIG_EXT4_DEBUG
        {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
 #endif
@@ -2040,6 +2042,8 @@ static const struct mount_opts {
         MOPT_SET},
        {Opt_no_fc, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
         MOPT_CLEAR | MOPT_2 | MOPT_EXT4_ONLY},
+       {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
+        MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
 #ifdef CONFIG_EXT4_DEBUG
        {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
 #endif