smb: move FILE_SYSTEM_ATTRIBUTE_INFO to common/fscc.h

Modify the following places:

- struct filesystem_attribute_info -> FILE_SYSTEM_ATTRIBUTE_INFO
- Remove MIN_FS_ATTR_INFO_SIZE definition
- Introduce MAX_FS_NAME_LEN
- max_len of FileFsAttributeInformation -> sizeof(FILE_SYSTEM_ATTRIBUTE_INFO) + MAX_FS_NAME_LEN
- min_len of FileFsAttributeInformation -> sizeof(FILE_SYSTEM_ATTRIBUTE_INFO)
- SMB2_QFS_attr(): memcpy(..., min_len)

Then move FILE_SYSTEM_ATTRIBUTE_INFO to common header file.

I have tested the relevant code related to FILE_SYSTEM_ATTRIBUTE_INFO (Link[1]).

Link[1]: https://chenxiaosong.com/en/FILE_SYSTEM_ATTRIBUTE_INFO.html
Suggested-by: Namjae Jeon <[e-mail]>
Tested-by: ChenXiaoSong <[e-mail]>
Signed-off-by: ChenXiaoSong <[e-mail]>
Acked-by: Namjae Jeon <[e-mail]>
Signed-off-by: Steve French <[e-mail]>

fs/smb/client/cifspdu.h

···
 #define FILE_PORTABLE_DEVICE			0x00004000
 #define FILE_DEVICE_ALLOW_APPCONTAINER_TRAVERSAL 0x00020000
 
-/* minimum includes first three fields, and empty FS Name */
-#define MIN_FS_ATTR_INFO_SIZE 12
-
-typedef struct {
-	__le32 Attributes;
-	__le32 MaxPathNameComponentLength;
-	__le32 FileSystemNameLen;
-	char FileSystemName[52]; /* do not have to save this - get subset? */
-} __attribute__((packed)) FILE_SYSTEM_ATTRIBUTE_INFO;
-
 /******************************************************************************/
 /* QueryFileInfo/QueryPathinfo (also for SetPath/SetFile) data buffer formats */
 /******************************************************************************/

fs/smb/client/smb2pdu.c

···
 		max_len = sizeof(FILE_SYSTEM_DEVICE_INFO);
 		min_len = sizeof(FILE_SYSTEM_DEVICE_INFO);
 	} else if (level == FS_ATTRIBUTE_INFORMATION) {
-		max_len = sizeof(FILE_SYSTEM_ATTRIBUTE_INFO);
-		min_len = MIN_FS_ATTR_INFO_SIZE;
+		max_len = sizeof(FILE_SYSTEM_ATTRIBUTE_INFO) + MAX_FS_NAME_LEN;
+		min_len = sizeof(FILE_SYSTEM_ATTRIBUTE_INFO);
 	} else if (level == FS_SECTOR_SIZE_INFORMATION) {
 		max_len = sizeof(struct smb3_fs_ss_info);
 		min_len = sizeof(struct smb3_fs_ss_info);
···
 	if (level == FS_ATTRIBUTE_INFORMATION)
 		memcpy(&tcon->fsAttrInfo, offset
 			+ (char *)rsp, min_t(unsigned int,
-			rsp_len, max_len));
+			rsp_len, min_len));
 	else if (level == FS_DEVICE_INFORMATION)
 		memcpy(&tcon->fsDevInfo, offset
 			+ (char *)rsp, sizeof(FILE_SYSTEM_DEVICE_INFO));

fs/smb/common/fscc.h

···
 	__le32 Reserved;
 } __packed; /* level 34 Query also similar returned in close rsp and open rsp */
 
+/* See MS-FSCC 2.5.1 */
+#define MAX_FS_NAME_LEN		52
+typedef struct {
+	__le32 Attributes;
+	__le32 MaxPathNameComponentLength;
+	__le32 FileSystemNameLen;
+	__le16 FileSystemName[]; /* do not have to save this - get subset? */
+} __packed FILE_SYSTEM_ATTRIBUTE_INFO;
+
 /* List of FileSystemAttributes - see MS-FSCC 2.5.1 */
 #define FILE_SUPPORTS_SPARSE_VDL	0x10000000 /* faster nonsparse extend */
 #define FILE_SUPPORTS_BLOCK_REFCOUNTING	0x08000000 /* allow ioctl dup extents */

fs/smb/server/smb2pdu.c

···
 	}
 	case FS_ATTRIBUTE_INFORMATION:
 	{
-		struct filesystem_attribute_info *info;
+		FILE_SYSTEM_ATTRIBUTE_INFO *info;
 		size_t sz;
 
-		info = (struct filesystem_attribute_info *)rsp->Buffer;
+		info = (FILE_SYSTEM_ATTRIBUTE_INFO *)rsp->Buffer;
 		info->Attributes = cpu_to_le32(FILE_SUPPORTS_OBJECT_IDS |
 					       FILE_PERSISTENT_ACLS |
 					       FILE_UNICODE_ON_DISK |
···
 					"NTFS", PATH_MAX, conn->local_nls, 0);
 		len = len * 2;
 		info->FileSystemNameLen = cpu_to_le32(len);
-		sz = sizeof(struct filesystem_attribute_info) + len;
+		sz = sizeof(FILE_SYSTEM_ATTRIBUTE_INFO) + len;
 		rsp->OutputBufferLength = cpu_to_le32(sz);
 		break;
 	}

fs/smb/server/smb_common.h

···
 	__le16 ByteCount;
 } __packed;
 
-struct filesystem_attribute_info {
-	__le32 Attributes;
-	__le32 MaxPathNameComponentLength;
-	__le32 FileSystemNameLen;
-	__le16 FileSystemName[]; /* do not have to save this - get subset? */
-} __packed;
-
 struct filesystem_vol_info {
 	__le64 VolumeCreationTime;
 	__le32 SerialNumber;