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>

5 files changed, 94 insertions, 4 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];
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index b5ec2a268f56..aa3397620342 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -360,6 +360,8 @@ extern int CIFSSMBUnixQuerySymLink(const unsigned int xid,
 extern int CIFSSMBQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
                                __u16 fid, char **symlinkinfo,
                                const struct nls_table *nls_codepage);
+extern int CIFSSMB_set_compression(const unsigned int xid,
+                                   struct cifs_tcon *tcon, __u16 fid);
 extern int CIFSSMBOpen(const unsigned int xid, struct cifs_tcon *tcon,
                         const char *fileName, const int disposition,
                         const int access_flags, const int omode,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index ccd31ab815d4..93b29474714a 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -3199,6 +3199,60 @@ qreparse_out:
         return rc;
 }
 
+int
+CIFSSMB_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
+                    __u16 fid)
+{
+        int rc = 0;
+        int bytes_returned;
+        struct smb_com_transaction_compr_ioctl_req *pSMB;
+        struct smb_com_transaction_ioctl_rsp *pSMBr;
+
+        cifs_dbg(FYI, "Set compression for %u\n", fid);
+        rc = smb_init(SMB_COM_NT_TRANSACT, 23, tcon, (void **) &pSMB,
+                      (void **) &pSMBr);
+        if (rc)
+                return rc;
+
+        pSMB->compression_state = cpu_to_le16(COMPRESSION_FORMAT_DEFAULT);
+
+        pSMB->TotalParameterCount = 0;
+        pSMB->TotalDataCount = __constant_cpu_to_le32(2);
+        pSMB->MaxParameterCount = 0;
+        pSMB->MaxDataCount = 0;
+        pSMB->MaxSetupCount = 4;
+        pSMB->Reserved = 0;
+        pSMB->ParameterOffset = 0;
+        pSMB->DataCount = __constant_cpu_to_le32(2);
+        pSMB->DataOffset =
+                cpu_to_le32(offsetof(struct smb_com_transaction_compr_ioctl_req,
+                                compression_state) - 4);  /* 84 */
+        pSMB->SetupCount = 4;
+        pSMB->SubCommand = __constant_cpu_to_le16(NT_TRANSACT_IOCTL);
+        pSMB->ParameterCount = 0;
+        pSMB->FunctionCode = __constant_cpu_to_le32(FSCTL_SET_COMPRESSION);
+        pSMB->IsFsctl = 1; /* FSCTL */
+        pSMB->IsRootFlag = 0;
+        pSMB->Fid = fid; /* file handle always le */
+        /* 3 byte pad, followed by 2 byte compress state */
+        pSMB->ByteCount = __constant_cpu_to_le16(5);
+        inc_rfc1001_len(pSMB, 5);
+
+        rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+                         (struct smb_hdr *) pSMBr, &bytes_returned, 0);
+        if (rc)
+                cifs_dbg(FYI, "Send error in SetCompression = %d\n", rc);
+
+        cifs_buf_release(pSMB);
+
+        /*
+         * Note: On -EAGAIN error only caller can retry on handle based calls
+         * since file handle passed in no longer valid.
+         */
+        return rc;
+}
+
+
 #ifdef CONFIG_CIFS_POSIX
 
 /*Convert an Access Control Entry from wire format to local POSIX xattr format*/
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index 09ef8f322c2a..384cffe42850 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -807,6 +807,13 @@ out:
 }
 
 static int
+cifs_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
+                   struct cifsFileInfo *cfile)
+{
+        return CIFSSMB_set_compression(xid, tcon, cfile->fid.netfid);
+}
+
+static int
 cifs_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
                      const char *path, struct cifs_sb_info *cifs_sb,
                      struct cifs_fid *fid, __u16 search_flags,
@@ -956,6 +963,7 @@ struct smb_version_operations smb1_operations = {
         .set_path_size = CIFSSMBSetEOF,
         .set_file_size = CIFSSMBSetFileSize,
         .set_file_info = smb_set_file_info,
+        .set_compression = cifs_set_compression,
         .echo = CIFSSMBEcho,
         .mkdir = CIFSSMBMkDir,
         .mkdir_setinfo = cifs_mkdir_setinfo,
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 7e44f18cc169..6183b1b7550f 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -570,12 +570,9 @@ struct network_interface_info_ioctl_rsp {
 #define NO_FILE_ID 0xFFFFFFFFFFFFFFFFULL /* general ioctls to srv not to file */
 
 struct compress_ioctl {
-        __le16 CompressionState;
+        __le16 CompressionState; /* See cifspdu.h for possible flag values */
 } __packed;
 
-#define COMPRESSION_FORMAT_NONE         0x0000
-#define COMPRESSION_FORMAT_DEFAULT      0x0001
-#define COMPRESSION_FORMAT_LZNT1        0x0002
 struct smb2_ioctl_req {
         struct smb2_hdr hdr;
         __le16 StructureSize;   /* Must be 57 */