Allow setting per-file compression via CIFS protocol

An earlier patch allowed setting the per-file compression flag

"chattr +c filename"

on an smb2 or smb3 mount, and also allowed lsattr to return
whether a file on a cifs, or smb2/smb3 mount was compressed.

This patch extends the ability to set the per-file
compression flag to the cifs protocol, which uses a somewhat
different IOCTL mechanism than SMB2, although the payload
(the flags stored in the compression_state) are the same.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h
index f80f98f5ef9c..9e5ee34de986 100644
--- a/fs/cifs/cifspdu.h
+++ b/fs/cifs/cifspdu.h
@@ -1352,6 +1352,35 @@ typedef struct smb_com_transaction_ioctl_req {
         __u8 Data[1];
 } __attribute__((packed)) TRANSACT_IOCTL_REQ;
 
+typedef struct smb_com_transaction_compr_ioctl_req {
+        struct smb_hdr hdr;     /* wct = 23 */
+        __u8 MaxSetupCount;
+        __u16 Reserved;
+        __le32 TotalParameterCount;
+        __le32 TotalDataCount;
+        __le32 MaxParameterCount;
+        __le32 MaxDataCount;
+        __le32 ParameterCount;
+        __le32 ParameterOffset;
+        __le32 DataCount;
+        __le32 DataOffset;
+        __u8 SetupCount; /* four setup words follow subcommand */
+        /* SNIA spec incorrectly included spurious pad here */
+        __le16 SubCommand; /* 2 = IOCTL/FSCTL */
+        __le32 FunctionCode;
+        __u16 Fid;
+        __u8 IsFsctl;  /* 1 = File System Control 0 = device control (IOCTL) */
+        __u8 IsRootFlag; /* 1 = apply command to root of share (must be DFS) */
+        __le16 ByteCount;
+        __u8 Pad[3];
+        __le16 compression_state;  /* See below for valid flags */
+} __attribute__((packed)) TRANSACT_COMPR_IOCTL_REQ;
+
+/* compression state flags */
+#define COMPRESSION_FORMAT_NONE         0x0000
+#define COMPRESSION_FORMAT_DEFAULT      0x0001
+#define COMPRESSION_FORMAT_LZNT1        0x0002
+
 typedef struct smb_com_transaction_ioctl_rsp {
         struct smb_hdr hdr;     /* wct = 19 */
         __u8 Reserved[3];