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>

8 files changed, 32 insertions, 27 deletions

diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 4ad4f94edebe..7bc5c82423ea 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -671,12 +671,12 @@ static int gfs2_write_begin(struct file *file, struct address_space *mapping,
 
         if (alloc_required) {
                 struct gfs2_alloc_parms ap = { .aflags = 0, };
-                error = gfs2_quota_lock_check(ip);
+                requested = data_blocks + ind_blocks;
+                ap.target = requested;
+                error = gfs2_quota_lock_check(ip, &ap);
                 if (error)
                         goto out_unlock;
 
-                requested = data_blocks + ind_blocks;
-                ap.target = requested;
                 error = gfs2_inplace_reserve(ip, &ap);
                 if (error)
                         goto out_qunlock;
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index f0b945ab853e..61296ecbd0e2 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -1224,7 +1224,7 @@ static int do_grow(struct inode *inode, u64 size)
 
         if (gfs2_is_stuffed(ip) &&
             (size > (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)))) {
-                error = gfs2_quota_lock_check(ip);
+                error = gfs2_quota_lock_check(ip, &ap);
                 if (error)
                         return error;
 
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 7353c0a01a1e..c569adbc1431 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -429,11 +429,11 @@ static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
         if (ret)
                 goto out_unlock;
 
-        ret = gfs2_quota_lock_check(ip);
-        if (ret)
-                goto out_unlock;
         gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
         ap.target = data_blocks + ind_blocks;
+        ret = gfs2_quota_lock_check(ip, &ap);
+        if (ret)
+                goto out_unlock;
         ret = gfs2_inplace_reserve(ip, &ap);
         if (ret)
                 goto out_quota_unlock;
@@ -827,13 +827,13 @@ static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t
                         offset += bytes;
                         continue;
                 }
-                error = gfs2_quota_lock_check(ip);
-                if (error)
-                        return error;
 retry:
                 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
-
                 ap.target = data_blocks + ind_blocks;
+
+                error = gfs2_quota_lock_check(ip, &ap);
+                if (error)
+                        return error;
                 error = gfs2_inplace_reserve(ip, &ap);
                 if (error) {
                         if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
@@ -841,6 +841,7 @@ retry:
                                 bytes &= bsize_mask;
                                 if (bytes == 0)
                                         bytes = sdp->sd_sb.sb_bsize;
+                                gfs2_quota_unlock(ip);
                                 goto retry;
                         }
                         goto out_qunlock;
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 7a2dbbc0d634..3a4ea50c9113 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -301,7 +301,7 @@ struct gfs2_blkreserv {
  * to the allocation code.
  */
 struct gfs2_alloc_parms {
-        u32 target;
+        u64 target;
         u32 aflags;
 };
 
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 73c72253faac..08bc84d7e768 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -382,7 +382,7 @@ static int alloc_dinode(struct gfs2_inode *ip, u32 flags, unsigned *dblocks)
         struct gfs2_alloc_parms ap = { .target = *dblocks, .aflags = flags, };
         int error;
 
-        error = gfs2_quota_lock_check(ip);
+        error = gfs2_quota_lock_check(ip, &ap);
         if (error)
                 goto out;
 
@@ -525,7 +525,7 @@ static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
         int error;
 
         if (da->nr_blocks) {
-                error = gfs2_quota_lock_check(dip);
+                error = gfs2_quota_lock_check(dip, &ap);
                 if (error)
                         goto fail_quota_locks;
 
@@ -953,7 +953,7 @@ static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
 
         if (da.nr_blocks) {
                 struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
-                error = gfs2_quota_lock_check(dip);
+                error = gfs2_quota_lock_check(dip, &ap);
                 if (error)
                         goto out_gunlock;
 
@@ -1470,7 +1470,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 
         if (da.nr_blocks) {
                 struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
-                error = gfs2_quota_lock_check(ndip);
+                error = gfs2_quota_lock_check(ndip, &ap);
                 if (error)
                         goto out_gunlock;
 
@@ -1669,6 +1669,7 @@ static int setattr_chown(struct inode *inode, struct iattr *attr)
         kuid_t ouid, nuid;
         kgid_t ogid, ngid;
         int error;
+        struct gfs2_alloc_parms ap;
 
         ouid = inode->i_uid;
         ogid = inode->i_gid;
@@ -1696,9 +1697,11 @@ static int setattr_chown(struct inode *inode, struct iattr *attr)
         if (error)
                 goto out;
 
+        ap.target = gfs2_get_inode_blocks(&ip->i_inode);
+
         if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
             !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
-                error = gfs2_quota_check(ip, nuid, ngid);
+                error = gfs2_quota_check(ip, nuid, ngid, &ap);
                 if (error)
                         goto out_gunlock_q;
         }
@@ -1713,9 +1716,8 @@ static int setattr_chown(struct inode *inode, struct iattr *attr)
 
         if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
             !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
-                u64 blocks = gfs2_get_inode_blocks(&ip->i_inode);
-                gfs2_quota_change(ip, -blocks, ouid, ogid);
-                gfs2_quota_change(ip, blocks, nuid, ngid);
+                gfs2_quota_change(ip, -ap.target, ouid, ogid);
+                gfs2_quota_change(ip, ap.target, nuid, ngid);
         }
 
 out_end_trans:
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 3aa17d4d1cfc..964a769a7a86 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -1094,7 +1094,8 @@ static int print_message(struct gfs2_quota_data *qd, char *type)
         return 0;
 }
 
-int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
+int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
+                     struct gfs2_alloc_parms *ap)
 {
         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
         struct gfs2_quota_data *qd;
@@ -1117,14 +1118,13 @@ int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 
                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
                 spin_lock(&qd_lock);
-                value += qd->qd_change;
+                value += qd->qd_change + ap->target;
                 spin_unlock(&qd_lock);
 
                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
                         print_message(qd, "exceeded");
                         quota_send_warning(qd->qd_id,
                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
-
                         error = -EDQUOT;
                         break;
                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
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;
diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c
index 0b81f783f787..fd260ce8869a 100644
--- a/fs/gfs2/xattr.c
+++ b/fs/gfs2/xattr.c
@@ -732,7 +732,7 @@ static int ea_alloc_skeleton(struct gfs2_inode *ip, struct gfs2_ea_request *er,
         if (error)
                 return error;
 
-        error = gfs2_quota_lock_check(ip);
+        error = gfs2_quota_lock_check(ip, &ap);
         if (error)
                 return error;