quota: Split dquot_quota_sync() to writeback and cache flushing part

Split off part of dquot_quota_sync() which writes dquots into a quota file
to a separate function. In the next patch we will use the function from
filesystems and we do not want to abuse ->quota_sync quotactl callback more
than necessary.

Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

7 files changed, 29 insertions, 11 deletions

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index b97178e7d397..27b5cc7d6881 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -1108,7 +1108,7 @@ void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
         }
 }
 
-int gfs2_quota_sync(struct super_block *sb, int type, int wait)
+int gfs2_quota_sync(struct super_block *sb, int type)
 {
         struct gfs2_sbd *sdp = sb->s_fs_info;
         struct gfs2_quota_data **qda;
@@ -1154,7 +1154,7 @@ int gfs2_quota_sync(struct super_block *sb, int type, int wait)
 
 static int gfs2_quota_sync_timeo(struct super_block *sb, int type)
 {
-        return gfs2_quota_sync(sb, type, 0);
+        return gfs2_quota_sync(sb, type);
 }
 
 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
diff --git a/fs/gfs2/quota.h b/fs/gfs2/quota.h
index 90bf1c302a98..f25d98b87904 100644
--- a/fs/gfs2/quota.h
+++ b/fs/gfs2/quota.h
@@ -26,7 +26,7 @@ extern int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid);
 extern void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
                               u32 uid, u32 gid);
 
-extern int gfs2_quota_sync(struct super_block *sb, int type, int wait);
+extern int gfs2_quota_sync(struct super_block *sb, int type);
 extern int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id);
 
 extern int gfs2_quota_init(struct gfs2_sbd *sdp);
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 713e621c240b..313c329490e2 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -838,7 +838,7 @@ static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
         int error;
 
         flush_workqueue(gfs2_delete_workqueue);
-        gfs2_quota_sync(sdp->sd_vfs, 0, 1);
+        gfs2_quota_sync(sdp->sd_vfs, 0);
         gfs2_statfs_sync(sdp->sd_vfs, 0);
 
         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
diff --git a/fs/gfs2/sys.c b/fs/gfs2/sys.c
index 9c2592b1d5ff..73ecc34c4342 100644
--- a/fs/gfs2/sys.c
+++ b/fs/gfs2/sys.c
@@ -168,7 +168,7 @@ static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
         if (simple_strtol(buf, NULL, 0) != 1)
                 return -EINVAL;
 
-        gfs2_quota_sync(sdp->sd_vfs, 0, 1);
+        gfs2_quota_sync(sdp->sd_vfs, 0);
         return len;
 }
 
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 10cbe841cb7e..d679fc48ef27 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -595,12 +595,14 @@ out:
 }
 EXPORT_SYMBOL(dquot_scan_active);
 
-int dquot_quota_sync(struct super_block *sb, int type, int wait)
+/* Write all dquot structures to quota files */
+int dquot_writeback_dquots(struct super_block *sb, int type)
 {
         struct list_head *dirty;
         struct dquot *dquot;
         struct quota_info *dqopt = sb_dqopt(sb);
         int cnt;
+        int err, ret = 0;
 
         mutex_lock(&dqopt->dqonoff_mutex);
         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
@@ -624,7 +626,9 @@ int dquot_quota_sync(struct super_block *sb, int type, int wait)
                         atomic_inc(&dquot->dq_count);
                         spin_unlock(&dq_list_lock);
                         dqstats_inc(DQST_LOOKUPS);
-                        sb->dq_op->write_dquot(dquot);
+                        err = sb->dq_op->write_dquot(dquot);
+                        if (!ret && err)
+                                err = ret;
                         dqput(dquot);
                         spin_lock(&dq_list_lock);
                 }
@@ -638,7 +642,21 @@ int dquot_quota_sync(struct super_block *sb, int type, int wait)
         dqstats_inc(DQST_SYNCS);
         mutex_unlock(&dqopt->dqonoff_mutex);
 
-        if (!wait || (dqopt->flags & DQUOT_QUOTA_SYS_FILE))
+        return ret;
+}
+EXPORT_SYMBOL(dquot_writeback_dquots);
+
+/* Write all dquot structures to disk and make them visible from userspace */
+int dquot_quota_sync(struct super_block *sb, int type)
+{
+        struct quota_info *dqopt = sb_dqopt(sb);
+        int cnt;
+        int ret;
+
+        ret = dquot_writeback_dquots(sb, type);
+        if (ret)
+                return ret;
+        if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
                 return 0;
 
         /* This is not very clever (and fast) but currently I don't know about
diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index 9a391204ca27..c659f92298d3 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -47,7 +47,7 @@ static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
 static void quota_sync_one(struct super_block *sb, void *arg)
 {
         if (sb->s_qcop && sb->s_qcop->quota_sync)
-                sb->s_qcop->quota_sync(sb, *(int *)arg, 1);
+                sb->s_qcop->quota_sync(sb, *(int *)arg);
 }
 
 static int quota_sync_all(int type)
@@ -270,7 +270,7 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
         case Q_SYNC:
                 if (!sb->s_qcop->quota_sync)
                         return -ENOSYS;
-                return sb->s_qcop->quota_sync(sb, type, 1);
+                return sb->s_qcop->quota_sync(sb, type);
         case Q_XQUOTAON:
         case Q_XQUOTAOFF:
         case Q_XQUOTARM:
diff --git a/fs/sync.c b/fs/sync.c
index b3d2a001293f..cae145dd8018 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -30,7 +30,7 @@
 static int __sync_filesystem(struct super_block *sb, int wait)
 {
         if (sb->s_qcop && sb->s_qcop->quota_sync)
-                sb->s_qcop->quota_sync(sb, -1, wait);
+                sb->s_qcop->quota_sync(sb, -1);
 
         if (wait)
                 sync_inodes_sb(sb);