ext4: make trim/discard optional (and off by default)

[mirror_ubuntu-bionic-kernel.git] / fs / ext4 / super.c

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index f2d5ec77c1e95f64b1ef7c945c8b68cb2b660b52..2b382f6f80c1c888536119076dc65a41ed7fcd08 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -899,6 +899,9 @@ static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
        if (test_opt(sb, NO_AUTO_DA_ALLOC))
                seq_puts(seq, ",noauto_da_alloc");
 
+       if (test_opt(sb, DISCARD))
+               seq_puts(seq, ",discard");
+
        ext4_show_quota_options(seq, sb);
 
        return 0;
@@ -1079,7 +1082,8 @@ enum {
        Opt_usrquota, Opt_grpquota, Opt_i_version,
        Opt_stripe, Opt_delalloc, Opt_nodelalloc,
        Opt_block_validity, Opt_noblock_validity,
-       Opt_inode_readahead_blks, Opt_journal_ioprio
+       Opt_inode_readahead_blks, Opt_journal_ioprio,
+       Opt_discard, Opt_nodiscard,
 };
 
 static const match_table_t tokens = {
@@ -1144,6 +1148,8 @@ static const match_table_t tokens = {
        {Opt_auto_da_alloc, "auto_da_alloc=%u"},
        {Opt_auto_da_alloc, "auto_da_alloc"},
        {Opt_noauto_da_alloc, "noauto_da_alloc"},
+       {Opt_discard, "discard"},
+       {Opt_nodiscard, "nodiscard"},
        {Opt_err, NULL},
 };
 
@@ -1565,6 +1571,12 @@ set_qf_format:
                        else
                                set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
                        break;
+               case Opt_discard:
+                       set_opt(sbi->s_mount_opt, DISCARD);
+                       break;
+               case Opt_nodiscard:
+                       clear_opt(sbi->s_mount_opt, DISCARD);
+                       break;
                default:
                        ext4_msg(sb, KERN_ERR,
                               "Unrecognized mount option \"%s\" "