[PATCH v3 1/2] ext4: add helpers for checking whether quota can be enabled/is journalled

[PATCH v3 1/2] ext4: add helpers for checking whether quota can be enabled/is journalled

[Roman Anufriev]

Right now, there are several places, where we check whether fs is
capable of enabling quota or if quota is journalled with quite long
and non-self-descriptive condition statements.

This patch wraps these statements into helpers for better readability
and easier usage.

Signed-off-by: Roman Anufriev <dotdot@yandex-team.ru>
---
Changes in v3:
  - nothing
Changes in v2:
  - Fix misleading helper name 'ext4_any_quota_enabled()' ->
    'ext4_quota_capable()'.

 fs/ext4/ext4.h      | 15 +++++++++++++++
 fs/ext4/ext4_jbd2.h |  9 +++------
 fs/ext4/super.c     |  5 +----
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 250e905..897df24 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3251,6 +3251,21 @@ static inline void ext4_unlock_group(struct super_block *sb,
 	spin_unlock(ext4_group_lock_ptr(sb, group));
 }
 
+#ifdef CONFIG_QUOTA
+static inline bool ext4_quota_capable(struct super_block *sb)
+{
+	return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
+}
+
+static inline bool ext4_is_quota_journalled(struct super_block *sb)
+{
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+	return (ext4_has_feature_quota(sb) ||
+		sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
+}
+#endif
+
 /*
  * Block validity checking
  */
diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h
index 00dc668..a124c68 100644
--- a/fs/ext4/ext4_jbd2.h
+++ b/fs/ext4/ext4_jbd2.h
@@ -86,17 +86,14 @@
 #ifdef CONFIG_QUOTA
 /* Amount of blocks needed for quota update - we know that the structure was
  * allocated so we need to update only data block */
-#define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
-		ext4_has_feature_quota(sb)) ? 1 : 0)
+#define EXT4_QUOTA_TRANS_BLOCKS(sb) ((ext4_quota_capable(sb)) ? 1 : 0)
 /* Amount of blocks needed for quota insert/delete - we do some block writes
  * but inode, sb and group updates are done only once */
-#define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
-		ext4_has_feature_quota(sb)) ?\
+#define EXT4_QUOTA_INIT_BLOCKS(sb) ((ext4_quota_capable(sb)) ?\
 		(DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
 		 +3+DQUOT_INIT_REWRITE) : 0)
 
-#define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
-		ext4_has_feature_quota(sb)) ?\
+#define EXT4_QUOTA_DEL_BLOCKS(sb) ((ext4_quota_capable(sb)) ?\
 		(DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
 		 +3+DQUOT_DEL_REWRITE) : 0)
 #else
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 9d01318..a988cf3 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -6158,11 +6158,8 @@ static int ext4_release_dquot(struct dquot *dquot)
 static int ext4_mark_dquot_dirty(struct dquot *dquot)
 {
 	struct super_block *sb = dquot->dq_sb;
-	struct ext4_sb_info *sbi = EXT4_SB(sb);
 
-	/* Are we journaling quotas? */
-	if (ext4_has_feature_quota(sb) ||
-	    sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
+	if (ext4_is_quota_journalled(sb)) {
 		dquot_mark_dquot_dirty(dquot);
 		return ext4_write_dquot(dquot);
 	} else {
-- 
2.7.4

[PATCH v3 2/2] ext4: print quota journalling mode on (re-)mount

[Roman Anufriev]

Right now, it is hard to understand what quota journalling type is enabled:
you need to be quite familiar with kernel code and trace it or really
understand what different combinations of fs flags/mount options lead to.

This patch adds printing of current quota jounalling mode on each
mount/remount, thus making it easier to check it at a glance/in autotests.
The semantics is similar to ext4 data journalling modes:

* journalled - quota accounting and journaling are enabled
* writeback  - quota accounting is enabled, but journalling is disabled
* none       - quota accounting is disabled
* disabled   - kernel compiled without CONFIG_QUOTA feature

Signed-off-by: Roman Anufriev <dotdot@yandex-team.ru>
---
Changes in v3:
  - Fix missing semicolon
Changes in v2:
  - Print quota journalling mode instead of exporting it via sysfs.

 fs/ext4/super.c | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index a988cf3..01815d3 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3985,6 +3985,21 @@ static void ext4_set_resv_clusters(struct super_block *sb)
 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
 }
 
+static const char *ext4_quota_mode(struct super_block *sb)
+{
+#ifdef CONFIG_QUOTA
+	if (!ext4_quota_capable(sb))
+		return "none";
+
+	if (ext4_is_quota_journalled(sb))
+		return "journalled";
+	else
+		return "writeback";
+#else
+	return "disabled";
+#endif
+}
+
 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 {
 	struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
@@ -5039,10 +5054,11 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 
 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
 		ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
-			 "Opts: %.*s%s%s", descr,
+			 "Opts: %.*s%s%s. Quota mode: %s.", descr,
 			 (int) sizeof(sbi->s_es->s_mount_opts),
 			 sbi->s_es->s_mount_opts,
-			 *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
+			 *sbi->s_es->s_mount_opts ? "; " : "", orig_data,
+			 ext4_quota_mode(sb));
 
 	if (es->s_error_count)
 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
@@ -5979,7 +5995,8 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data)
 	 */
 	*flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
 
-	ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
+	ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s. Quota mode: %s.",
+		 orig_data, ext4_quota_mode(sb));
 	kfree(orig_data);
 	return 0;
 
-- 
2.7.4