CIFS: Add SMB2 support for cifs_iovec_read
authorPavel Shilovsky <pshilovsky@samba.org>
Tue, 18 Sep 2012 23:20:29 +0000 (16:20 -0700)
committerSteve French <smfrench@gmail.com>
Tue, 25 Sep 2012 02:46:27 +0000 (21:46 -0500)
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
fs/cifs/cifsglob.h
fs/cifs/cifsproto.h
fs/cifs/cifssmb.c
fs/cifs/file.c
fs/cifs/smb2glob.h
fs/cifs/smb2misc.c
fs/cifs/smb2ops.c
fs/cifs/smb2pdu.c
fs/cifs/smb2pdu.h
fs/cifs/smb2proto.h

index fcf81c0..93dd582 100644 (file)
@@ -857,12 +857,37 @@ struct cifsFileInfo {
 
 struct cifs_io_parms {
        __u16 netfid;
+#ifdef CONFIG_CIFS_SMB2
+       __u64 persistent_fid;   /* persist file id for smb2 */
+       __u64 volatile_fid;     /* volatile file id for smb2 */
+#endif
        __u32 pid;
        __u64 offset;
        unsigned int length;
        struct cifs_tcon *tcon;
 };
 
+struct cifs_readdata;
+
+/* asynchronous read support */
+struct cifs_readdata {
+       struct kref                     refcount;
+       struct list_head                list;
+       struct completion               done;
+       struct cifsFileInfo             *cfile;
+       struct address_space            *mapping;
+       __u64                           offset;
+       unsigned int                    bytes;
+       pid_t                           pid;
+       int                             result;
+       struct list_head                pages;
+       struct work_struct              work;
+       int (*marshal_iov) (struct cifs_readdata *rdata,
+                           unsigned int remaining);
+       unsigned int                    nr_iov;
+       struct kvec                     iov[1];
+};
+
 /*
  * Take a reference on the file private data. Must be called with
  * cifs_file_list_lock held.
index 2c6ad78..6656eb5 100644 (file)
@@ -464,27 +464,9 @@ extern int E_md4hash(const unsigned char *passwd, unsigned char *p16,
 extern int SMBencrypt(unsigned char *passwd, const unsigned char *c8,
                        unsigned char *p24);
 
-/* asynchronous read support */
-struct cifs_readdata {
-       struct kref                     refcount;
-       struct list_head                list;
-       struct completion               done;
-       struct cifsFileInfo             *cfile;
-       struct address_space            *mapping;
-       __u64                           offset;
-       unsigned int                    bytes;
-       pid_t                           pid;
-       int                             result;
-       struct list_head                pages;
-       struct work_struct              work;
-       int (*marshal_iov) (struct cifs_readdata *rdata,
-                           unsigned int remaining);
-       unsigned int                    nr_iov;
-       struct kvec                     iov[1];
-};
-
 void cifs_readdata_release(struct kref *refcount);
 int cifs_async_readv(struct cifs_readdata *rdata);
+int cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid);
 
 /* asynchronous write support */
 struct cifs_writedata {
index 4c48b9c..8a07f21 100644 (file)
@@ -1440,7 +1440,7 @@ cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
        return 0;
 }
 
-static int
+int
 cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 {
        int length, len;
index ec7c2e6..29ac8ee 100644 (file)
@@ -2732,6 +2732,10 @@ restart_loop:
        cifs_stats_bytes_read(tcon, total_read);
        *poffset += total_read;
 
+       /* mask nodata case */
+       if (rc == -ENODATA)
+               rc = 0;
+
        return total_read ? total_read : rc;
 }
 
index 33c1d89..11505d7 100644 (file)
 #define SMB2_OP_RENAME 6
 #define SMB2_OP_DELETE 7
 
+/* Used when constructing chained read requests. */
+#define CHAINED_REQUEST 1
+#define START_OF_CHAIN 2
+#define END_OF_CHAIN 4
+#define RELATED_REQUEST 8
+
 #endif /* _SMB2_GLOB_H */
index e4d3b99..9275883 100644 (file)
@@ -244,6 +244,9 @@ smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
                    ((struct smb2_query_info_rsp *)hdr)->OutputBufferLength);
                break;
        case SMB2_READ:
+               *off = ((struct smb2_read_rsp *)hdr)->DataOffset;
+               *len = le32_to_cpu(((struct smb2_read_rsp *)hdr)->DataLength);
+               break;
        case SMB2_QUERY_DIRECTORY:
        case SMB2_IOCTL:
        case SMB2_CHANGE_NOTIFY:
index 20afb75..d9ca357 100644 (file)
@@ -379,6 +379,20 @@ smb2_flush_file(const unsigned int xid, struct cifs_tcon *tcon,
        return SMB2_flush(xid, tcon, fid->persistent_fid, fid->volatile_fid);
 }
 
+static unsigned int
+smb2_read_data_offset(char *buf)
+{
+       struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;
+       return rsp->DataOffset;
+}
+
+static unsigned int
+smb2_read_data_length(char *buf)
+{
+       struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;
+       return le32_to_cpu(rsp->DataLength);
+}
+
 struct smb_version_operations smb21_operations = {
        .setup_request = smb2_setup_request,
        .setup_async_request = smb2_setup_async_request,
@@ -388,6 +402,9 @@ struct smb_version_operations smb21_operations = {
        .get_credits_field = smb2_get_credits_field,
        .get_credits = smb2_get_credits,
        .get_next_mid = smb2_get_next_mid,
+       .read_data_offset = smb2_read_data_offset,
+       .read_data_length = smb2_read_data_length,
+       .map_error = map_smb2_to_linux_error,
        .find_mid = smb2_find_mid,
        .check_message = smb2_check_message,
        .dump_detail = smb2_dump_detail,
@@ -416,12 +433,14 @@ struct smb_version_operations smb21_operations = {
        .set_fid = smb2_set_fid,
        .close = smb2_close_file,
        .flush = smb2_flush_file,
+       .async_readv = smb2_async_readv,
 };
 
 struct smb_version_values smb21_values = {
        .version_string = SMB21_VERSION_STRING,
        .header_size = sizeof(struct smb2_hdr),
        .max_header_size = MAX_SMB2_HDR_SIZE,
+       .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
index ff37406..e186718 100644 (file)
@@ -31,6 +31,7 @@
 #include <linux/fs.h>
 #include <linux/kernel.h>
 #include <linux/vfs.h>
+#include <linux/task_io_accounting_ops.h>
 #include <linux/uaccess.h>
 #include <linux/xattr.h>
 #include "smb2pdu.h"
@@ -42,6 +43,7 @@
 #include "cifs_debug.h"
 #include "ntlmssp.h"
 #include "smb2status.h"
+#include "smb2glob.h"
 
 /*
  *  The following table defines the expected "StructureSize" of SMB2 requests
@@ -1190,3 +1192,138 @@ SMB2_flush(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
        free_rsp_buf(resp_buftype, iov[0].iov_base);
        return rc;
 }
+
+/*
+ * To form a chain of read requests, any read requests after the first should
+ * have the end_of_chain boolean set to true.
+ */
+static int
+smb2_new_read_req(struct kvec *iov, struct cifs_io_parms *io_parms,
+                 unsigned int remaining_bytes, int request_type)
+{
+       int rc = -EACCES;
+       struct smb2_read_req *req = NULL;
+
+       rc = small_smb2_init(SMB2_READ, io_parms->tcon, (void **) &req);
+       if (rc)
+               return rc;
+       if (io_parms->tcon->ses->server == NULL)
+               return -ECONNABORTED;
+
+       req->hdr.ProcessId = cpu_to_le32(io_parms->pid);
+
+       req->PersistentFileId = io_parms->persistent_fid;
+       req->VolatileFileId = io_parms->volatile_fid;
+       req->ReadChannelInfoOffset = 0; /* reserved */
+       req->ReadChannelInfoLength = 0; /* reserved */
+       req->Channel = 0; /* reserved */
+       req->MinimumCount = 0;
+       req->Length = cpu_to_le32(io_parms->length);
+       req->Offset = cpu_to_le64(io_parms->offset);
+
+       if (request_type & CHAINED_REQUEST) {
+               if (!(request_type & END_OF_CHAIN)) {
+                       /* 4 for rfc1002 length field */
+                       req->hdr.NextCommand =
+                               cpu_to_le32(get_rfc1002_length(req) + 4);
+               } else /* END_OF_CHAIN */
+                       req->hdr.NextCommand = 0;
+               if (request_type & RELATED_REQUEST) {
+                       req->hdr.Flags |= SMB2_FLAGS_RELATED_OPERATIONS;
+                       /*
+                        * Related requests use info from previous read request
+                        * in chain.
+                        */
+                       req->hdr.SessionId = 0xFFFFFFFF;
+                       req->hdr.TreeId = 0xFFFFFFFF;
+                       req->PersistentFileId = 0xFFFFFFFF;
+                       req->VolatileFileId = 0xFFFFFFFF;
+               }
+       }
+       if (remaining_bytes > io_parms->length)
+               req->RemainingBytes = cpu_to_le32(remaining_bytes);
+       else
+               req->RemainingBytes = 0;
+
+       iov[0].iov_base = (char *)req;
+       /* 4 for rfc1002 length field */
+       iov[0].iov_len = get_rfc1002_length(req) + 4;
+       return rc;
+}
+
+static void
+smb2_readv_callback(struct mid_q_entry *mid)
+{
+       struct cifs_readdata *rdata = mid->callback_data;
+       struct cifs_tcon *tcon = tlink_tcon(rdata->cfile->tlink);
+       struct TCP_Server_Info *server = tcon->ses->server;
+       struct smb2_hdr *buf = (struct smb2_hdr *)rdata->iov[0].iov_base;
+       unsigned int credits_received = 1;
+
+       cFYI(1, "%s: mid=%llu state=%d result=%d bytes=%u", __func__,
+               mid->mid, mid->mid_state, rdata->result, rdata->bytes);
+
+       switch (mid->mid_state) {
+       case MID_RESPONSE_RECEIVED:
+               credits_received = le16_to_cpu(buf->CreditRequest);
+               /* result already set, check signature */
+               /* if (server->sec_mode &
+                   (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
+                       if (smb2_verify_signature(mid->resp_buf, server))
+                               cERROR(1, "Unexpected SMB signature"); */
+               /* FIXME: should this be counted toward the initiating task? */
+               task_io_account_read(rdata->bytes);
+               cifs_stats_bytes_read(tcon, rdata->bytes);
+               break;
+       case MID_REQUEST_SUBMITTED:
+       case MID_RETRY_NEEDED:
+               rdata->result = -EAGAIN;
+               break;
+       default:
+               if (rdata->result != -ENODATA)
+                       rdata->result = -EIO;
+       }
+
+       if (rdata->result)
+               cifs_stats_fail_inc(tcon, SMB2_READ_HE);
+
+       queue_work(cifsiod_wq, &rdata->work);
+       DeleteMidQEntry(mid);
+       add_credits(server, credits_received, 0);
+}
+
+/* smb2_async_readv - send an async write, and set up mid to handle result */
+int
+smb2_async_readv(struct cifs_readdata *rdata)
+{
+       int rc;
+       struct smb2_hdr *buf;
+       struct cifs_io_parms io_parms;
+
+       cFYI(1, "%s: offset=%llu bytes=%u", __func__,
+               rdata->offset, rdata->bytes);
+
+       io_parms.tcon = tlink_tcon(rdata->cfile->tlink);
+       io_parms.offset = rdata->offset;
+       io_parms.length = rdata->bytes;
+       io_parms.persistent_fid = rdata->cfile->fid.persistent_fid;
+       io_parms.volatile_fid = rdata->cfile->fid.volatile_fid;
+       io_parms.pid = rdata->pid;
+       rc = smb2_new_read_req(&rdata->iov[0], &io_parms, 0, 0);
+       if (rc)
+               return rc;
+
+       buf = (struct smb2_hdr *)rdata->iov[0].iov_base;
+       /* 4 for rfc1002 length field */
+       rdata->iov[0].iov_len = get_rfc1002_length(rdata->iov[0].iov_base) + 4;
+
+       kref_get(&rdata->refcount);
+       rc = cifs_call_async(io_parms.tcon->ses->server, rdata->iov, 1,
+                            cifs_readv_receive, smb2_readv_callback,
+                            rdata, 0);
+       if (rc)
+               kref_put(&rdata->refcount, cifs_readdata_release);
+
+       cifs_small_buf_release(buf);
+       return rc;
+}
index f5bf63f..4abb581 100644 (file)
@@ -468,6 +468,34 @@ struct smb2_flush_rsp {
        __le16 Reserved;
 } __packed;
 
+struct smb2_read_req {
+       struct smb2_hdr hdr;
+       __le16 StructureSize; /* Must be 49 */
+       __u8   Padding; /* offset from start of SMB2 header to place read */
+       __u8   Reserved;
+       __le32 Length;
+       __le64 Offset;
+       __u64  PersistentFileId; /* opaque endianness */
+       __u64  VolatileFileId; /* opaque endianness */
+       __le32 MinimumCount;
+       __le32 Channel; /* Reserved MBZ */
+       __le32 RemainingBytes;
+       __le16 ReadChannelInfoOffset; /* Reserved MBZ */
+       __le16 ReadChannelInfoLength; /* Reserved MBZ */
+       __u8   Buffer[1];
+} __packed;
+
+struct smb2_read_rsp {
+       struct smb2_hdr hdr;
+       __le16 StructureSize; /* Must be 17 */
+       __u8   DataOffset;
+       __u8   Reserved;
+       __le32 DataLength;
+       __le32 DataRemaining;
+       __u32  Reserved2;
+       __u8   Buffer[1];
+} __packed;
+
 struct smb2_echo_req {
        struct smb2_hdr hdr;
        __le16 StructureSize;   /* Must be 4 */
index 51e6cd1..f442e46 100644 (file)
@@ -97,6 +97,7 @@ extern int SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon,
 extern int SMB2_get_srv_num(const unsigned int xid, struct cifs_tcon *tcon,
                            u64 persistent_fid, u64 volatile_fid,
                            __le64 *uniqueid);
+extern int smb2_async_readv(struct cifs_readdata *rdata);
 extern int SMB2_echo(struct TCP_Server_Info *server);
 
 #endif                 /* _SMB2PROTO_H */