gfs2: perform quota checks against allocation parameters

Use struct gfs2_alloc_parms as an argument to gfs2_quota_check()
and gfs2_quota_lock_check() to check for quota violations while
accounting for the new blocks requested by the current operation
in ap->target.

Previously, the number of new blocks requested during an operation
were not accounted for during quota_check and would allow these
operations to exceed quota. This was not very apparent since most
operations allocated only 1 block at a time and quotas would get
violated in the next operation. i.e. quota excess would only be by
1 block or so. With fallocate, (where we allocate a bunch of blocks
at once) the quota excess is non-trivial and is addressed by this
patch.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/fs/gfs2/quota.h b/fs/gfs2/quota.h
index 55d506eb3c4a..ad04b3acae2b 100644
--- a/fs/gfs2/quota.h
+++ b/fs/gfs2/quota.h
@@ -24,7 +24,8 @@ extern void gfs2_quota_unhold(struct gfs2_inode *ip);
 extern int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid);
 extern void gfs2_quota_unlock(struct gfs2_inode *ip);
 
-extern int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid);
+extern int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
+                            struct gfs2_alloc_parms *ap);
 extern void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
                               kuid_t uid, kgid_t gid);
 
@@ -37,7 +38,8 @@ extern int gfs2_quotad(void *data);
 
 extern void gfs2_wake_up_statfs(struct gfs2_sbd *sdp);
 
-static inline int gfs2_quota_lock_check(struct gfs2_inode *ip)
+static inline int gfs2_quota_lock_check(struct gfs2_inode *ip,
+                                        struct gfs2_alloc_parms *ap)
 {
         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
         int ret;
@@ -48,7 +50,7 @@ static inline int gfs2_quota_lock_check(struct gfs2_inode *ip)
                 return ret;
         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
                 return 0;
-        ret = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
+        ret = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid, ap);
         if (ret)
                 gfs2_quota_unlock(ip);
         return ret;