ceph: quota: support for ceph.quota.max_bytes

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

4 files changed, 44 insertions, 1 deletions

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index c3042330e0e9..0a2843fdebbd 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1378,6 +1378,11 @@ retry_snap:
 
         pos = iocb->ki_pos;
         count = iov_iter_count(from);
+        if (ceph_quota_is_max_bytes_exceeded(inode, pos + count)) {
+                err = -EDQUOT;
+                goto out;
+        }
+
         err = file_remove_privs(file);
         if (err)
                 goto out;
@@ -1708,6 +1713,12 @@ static long ceph_fallocate(struct file *file, int mode,
                 goto unlock;
         }
 
+        if (!(mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE)) &&
+            ceph_quota_is_max_bytes_exceeded(inode, offset + length)) {
+                ret = -EDQUOT;
+                goto unlock;
+        }
+
         if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) &&
             !(mode & FALLOC_FL_PUNCH_HOLE)) {
                 ret = -ENOSPC;
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 2c6f8be4ed63..50ccae151ea0 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2147,6 +2147,10 @@ int ceph_setattr(struct dentry *dentry, struct iattr *attr)
         if (err != 0)
                 return err;
 
+        if ((attr->ia_valid & ATTR_SIZE) &&
+            ceph_quota_is_max_bytes_exceeded(inode, attr->ia_size))
+                return -EDQUOT;
+
         err = __ceph_setattr(inode, attr);
 
         if (err >= 0 && (attr->ia_valid & ATTR_MODE))
diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c
index 5d7dada91a57..745f9f47027b 100644
--- a/fs/ceph/quota.c
+++ b/fs/ceph/quota.c
@@ -134,7 +134,8 @@ bool ceph_quota_is_same_realm(struct inode *old, struct inode *new)
 }
 
 enum quota_check_op {
-        QUOTA_CHECK_MAX_FILES_OP        /* check quota max_files limit */
+        QUOTA_CHECK_MAX_FILES_OP,       /* check quota max_files limit */
+        QUOTA_CHECK_MAX_BYTES_OP        /* check quota max_files limit */
 };
 
 /*
@@ -171,6 +172,9 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op,
                 if (op == QUOTA_CHECK_MAX_FILES_OP) {
                         max = ci->i_max_files;
                         rvalue = ci->i_rfiles + ci->i_rsubdirs;
+                } else {
+                        max = ci->i_max_bytes;
+                        rvalue = ci->i_rbytes;
                 }
                 is_root = (ci->i_vino.ino == CEPH_INO_ROOT);
                 spin_unlock(&ci->i_ceph_lock);
@@ -178,6 +182,9 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op,
                 case QUOTA_CHECK_MAX_FILES_OP:
                         exceeded = (max && (rvalue >= max));
                         break;
+                case QUOTA_CHECK_MAX_BYTES_OP:
+                        exceeded = (max && (rvalue + delta > max));
+                        break;
                 default:
                         /* Shouldn't happen */
                         pr_warn("Invalid quota check op (%d)\n", op);
@@ -212,3 +219,22 @@ bool ceph_quota_is_max_files_exceeded(struct inode *inode)
 
         return check_quota_exceeded(inode, QUOTA_CHECK_MAX_FILES_OP, 0);
 }
+
+/*
+ * ceph_quota_is_max_bytes_exceeded - check if we can write to a file
+ * @inode:      inode being written
+ * @newsize:    new size if write succeeds
+ *
+ * This functions returns true is max_bytes quota allows a file size to reach
+ * @newsize; it returns false otherwise.
+ */
+bool ceph_quota_is_max_bytes_exceeded(struct inode *inode, loff_t newsize)
+{
+        loff_t size = i_size_read(inode);
+
+        /* return immediately if we're decreasing file size */
+        if (newsize <= size)
+                return false;
+
+        return check_quota_exceeded(inode, QUOTA_CHECK_MAX_BYTES_OP, (newsize - size));
+}
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index eea6f70f3bf9..5870c225c2fc 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1079,5 +1079,7 @@ extern void ceph_handle_quota(struct ceph_mds_client *mdsc,
                               struct ceph_msg *msg);
 extern bool ceph_quota_is_max_files_exceeded(struct inode *inode);
 extern bool ceph_quota_is_same_realm(struct inode *old, struct inode *new);
+extern bool ceph_quota_is_max_bytes_exceeded(struct inode *inode,
+                                             loff_t newlen);
 
 #endif /* _FS_CEPH_SUPER_H */