ceph: quota: support for ceph.quota.max_bytes

[mirror_ubuntu-bionic-kernel.git] / fs / ceph / quota.c

diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c
index fd27e7113731c81f39bcab956e5b5001802386a0..e324593a97714136d25e127cad58665e5c2463b3 100644 (file)
--- a/fs/ceph/quota.c
+++ b/fs/ceph/quota.c
@@ -136,7 +136,8 @@ 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 */
 };
 
 /*
@@ -172,12 +173,18 @@ 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;
                }
                spin_unlock(&ci->i_ceph_lock);
                switch (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));
+}