ext4: enable FITRIM ioctl on bigalloc file system

With a minor tweaks regarding minimum extent size to discard and
discarded bytes reporting the FITRIM can be enabled on bigalloc file
system and it works without any problem.

This patch fixes minlen handling and discarded bytes reporting to
take into consideration bigalloc enabled file systems and finally
removes the restriction and allow FITRIM to be used on file system with
bigalloc feature enabled.

Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

2 files changed, 3 insertions, 9 deletions

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 8b84fe28ccaf..4c8174aa685c 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -404,13 +404,6 @@ resizefs_out:
                 if (!blk_queue_discard(q))
                         return -EOPNOTSUPP;
 
-                if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
-                               EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
-                        ext4_msg(sb, KERN_ERR,
-                                 "FITRIM not supported with bigalloc");
-                        return -EOPNOTSUPP;
-                }
-
                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
                     sizeof(range)))
                         return -EFAULT;
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 8ec6f88b7a37..a415465f97a0 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4990,7 +4990,8 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
 
         start = range->start >> sb->s_blocksize_bits;
         end = start + (range->len >> sb->s_blocksize_bits) - 1;
-        minlen = range->minlen >> sb->s_blocksize_bits;
+        minlen = EXT4_NUM_B2C(EXT4_SB(sb),
+                              range->minlen >> sb->s_blocksize_bits);
 
         if (unlikely(minlen > EXT4_CLUSTERS_PER_GROUP(sb)) ||
             unlikely(start >= max_blks))
@@ -5050,6 +5051,6 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
                 atomic_set(&EXT4_SB(sb)->s_last_trim_minblks, minlen);
 
 out:
-        range->len = trimmed * sb->s_blocksize;
+        range->len = EXT4_C2B(EXT4_SB(sb), trimmed) << sb->s_blocksize_bits;
         return ret;
 }