CIFS: Add statfs support for SMB2

Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 81 insertions, 0 deletions

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 566d86b0ad9..994c184ac9a 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1971,3 +1971,84 @@ SMB2_oplock_break(const unsigned int xid, struct cifs_tcon *tcon,
 
 	return rc;
 }
+
+static void
+copy_fs_info_to_kstatfs(struct smb2_fs_full_size_info *pfs_inf,
+			struct kstatfs *kst)
+{
+	kst->f_bsize = le32_to_cpu(pfs_inf->BytesPerSector) *
+			  le32_to_cpu(pfs_inf->SectorsPerAllocationUnit);
+	kst->f_blocks = le64_to_cpu(pfs_inf->TotalAllocationUnits);
+	kst->f_bfree  = le64_to_cpu(pfs_inf->ActualAvailableAllocationUnits);
+	kst->f_bavail = le64_to_cpu(pfs_inf->CallerAvailableAllocationUnits);
+	return;
+}
+
+static int
+build_qfs_info_req(struct kvec *iov, struct cifs_tcon *tcon, int level,
+		   int outbuf_len, u64 persistent_fid, u64 volatile_fid)
+{
+	int rc;
+	struct smb2_query_info_req *req;
+
+	cFYI(1, "Query FSInfo level %d", level);
+
+	if ((tcon->ses == NULL) || (tcon->ses->server == NULL))
+		return -EIO;
+
+	rc = small_smb2_init(SMB2_QUERY_INFO, tcon, (void **) &req);
+	if (rc)
+		return rc;
+
+	req->InfoType = SMB2_O_INFO_FILESYSTEM;
+	req->FileInfoClass = level;
+	req->PersistentFileId = persistent_fid;
+	req->VolatileFileId = volatile_fid;
+	/* 4 for rfc1002 length field and 1 for pad */
+	req->InputBufferOffset =
+			cpu_to_le16(sizeof(struct smb2_query_info_req) - 1 - 4);
+	req->OutputBufferLength = cpu_to_le32(
+		outbuf_len + sizeof(struct smb2_query_info_rsp) - 1 - 4);
+
+	iov->iov_base = (char *)req;
+	/* 4 for rfc1002 length field */
+	iov->iov_len = get_rfc1002_length(req) + 4;
+	return 0;
+}
+
+int
+SMB2_QFS_info(const unsigned int xid, struct cifs_tcon *tcon,
+	      u64 persistent_fid, u64 volatile_fid, struct kstatfs *fsdata)
+{
+	struct smb2_query_info_rsp *rsp = NULL;
+	struct kvec iov;
+	int rc = 0;
+	int resp_buftype;
+	struct cifs_ses *ses = tcon->ses;
+	struct smb2_fs_full_size_info *info = NULL;
+
+	rc = build_qfs_info_req(&iov, tcon, FS_FULL_SIZE_INFORMATION,
+				sizeof(struct smb2_fs_full_size_info),
+				persistent_fid, volatile_fid);
+	if (rc)
+		return rc;
+
+	rc = SendReceive2(xid, ses, &iov, 1, &resp_buftype, 0);
+	if (rc) {
+		cifs_stats_fail_inc(tcon, SMB2_QUERY_INFO_HE);
+		goto qinf_exit;
+	}
+	rsp = (struct smb2_query_info_rsp *)iov.iov_base;
+
+	info = (struct smb2_fs_full_size_info *)(4 /* RFC1001 len */ +
+		le16_to_cpu(rsp->OutputBufferOffset) + (char *)&rsp->hdr);
+	rc = validate_buf(le16_to_cpu(rsp->OutputBufferOffset),
+			  le32_to_cpu(rsp->OutputBufferLength), &rsp->hdr,
+			  sizeof(struct smb2_fs_full_size_info));
+	if (!rc)
+		copy_fs_info_to_kstatfs(info, fsdata);
+
+qinf_exit:
+	free_rsp_buf(resp_buftype, iov.iov_base);
+	return rc;
+}