CIFS: Process oplocks for SMB2
[pandora-kernel.git] / fs / cifs / smb2pdu.c
index 62b3f17..e97c256 100644 (file)
@@ -31,7 +31,9 @@
 #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/pagemap.h>
 #include <linux/xattr.h>
 #include "smb2pdu.h"
 #include "cifsglob.h"
@@ -42,6 +44,8 @@
 #include "cifs_debug.h"
 #include "ntlmssp.h"
 #include "smb2status.h"
+#include "smb2glob.h"
+#include "cifspdu.h"
 
 /*
  *  The following table defines the expected "StructureSize" of SMB2 requests
@@ -115,9 +119,9 @@ smb2_hdr_assemble(struct smb2_hdr *hdr, __le16 smb2_cmd /* command */ ,
        /* BB how does SMB2 do case sensitive? */
        /* if (tcon->nocase)
                hdr->Flags |= SMBFLG_CASELESS; */
-       /* if (tcon->ses && tcon->ses->server &&
+       if (tcon->ses && tcon->ses->server &&
            (tcon->ses->server->sec_mode & SECMODE_SIGN_REQUIRED))
-               hdr->Flags |= SMB2_FLAGS_SIGNED; */
+               hdr->Flags |= SMB2_FLAGS_SIGNED;
 out:
        pdu->StructureSize2 = cpu_to_le16(parmsize);
        return;
@@ -438,6 +442,38 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
                rc = -EIO;
                goto neg_exit;
        }
+
+       cFYI(1, "sec_flags 0x%x", sec_flags);
+       if (sec_flags & CIFSSEC_MUST_SIGN) {
+               cFYI(1, "Signing required");
+               if (!(server->sec_mode & (SMB2_NEGOTIATE_SIGNING_REQUIRED |
+                     SMB2_NEGOTIATE_SIGNING_ENABLED))) {
+                       cERROR(1, "signing required but server lacks support");
+                       rc = -EOPNOTSUPP;
+                       goto neg_exit;
+               }
+               server->sec_mode |= SECMODE_SIGN_REQUIRED;
+       } else if (sec_flags & CIFSSEC_MAY_SIGN) {
+               cFYI(1, "Signing optional");
+               if (server->sec_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) {
+                       cFYI(1, "Server requires signing");
+                       server->sec_mode |= SECMODE_SIGN_REQUIRED;
+               } else {
+                       server->sec_mode &=
+                               ~(SECMODE_SIGN_ENABLED | SECMODE_SIGN_REQUIRED);
+               }
+       } else {
+               cFYI(1, "Signing disabled");
+               if (server->sec_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) {
+                       cERROR(1, "Server requires packet signing to be enabled"
+                                 " in /proc/fs/cifs/SecurityFlags.");
+                       rc = -EOPNOTSUPP;
+                       goto neg_exit;
+               }
+               server->sec_mode &=
+                       ~(SECMODE_SIGN_ENABLED | SECMODE_SIGN_REQUIRED);
+       }
+
 #ifdef CONFIG_SMB2_ASN1  /* BB REMOVEME when updated asn1.c ready */
        rc = decode_neg_token_init(security_blob, blob_length,
                                   &server->sec_type);
@@ -666,6 +702,8 @@ SMB2_logoff(const unsigned int xid, struct cifs_ses *ses)
 
         /* since no tcon, smb2_init can not do this, so do here */
        req->hdr.SessionId = ses->Suid;
+       if (server->sec_mode & SECMODE_SIGN_REQUIRED)
+               req->hdr.Flags |= SMB2_FLAGS_SIGNED;
 
        rc = SendReceiveNoRsp(xid, ses, (char *) &req->hdr, 0);
        /*
@@ -833,7 +871,8 @@ SMB2_tdis(const unsigned int xid, struct cifs_tcon *tcon)
 int
 SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
          u64 *persistent_fid, u64 *volatile_fid, __u32 desired_access,
-         __u32 create_disposition, __u32 file_attributes, __u32 create_options)
+         __u32 create_disposition, __u32 file_attributes, __u32 create_options,
+         __u8 *oplock, struct smb2_file_all_info *buf)
 {
        struct smb2_create_req *req;
        struct smb2_create_rsp *rsp;
@@ -856,8 +895,8 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
        if (rc)
                return rc;
 
-       if (enable_oplocks)
-               req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_BATCH;
+       if (server->oplocks)
+               req->RequestedOplockLevel = *oplock;
        else
                req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_NONE;
        req->ImpersonationLevel = IL_IMPERSONATION;
@@ -906,6 +945,17 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
        }
        *persistent_fid = rsp->PersistentFileId;
        *volatile_fid = rsp->VolatileFileId;
+
+       if (buf) {
+               memcpy(buf, &rsp->CreationTime, 32);
+               buf->AllocationSize = rsp->AllocationSize;
+               buf->EndOfFile = rsp->EndofFile;
+               buf->Attributes = rsp->FileAttributes;
+               buf->NumberOfLinks = cpu_to_le32(1);
+               buf->DeletePending = 0;
+       }
+
+       *oplock = rsp->OplockLevel;
 creat_exit:
        free_rsp_buf(resp_buftype, rsp);
        return rc;
@@ -1019,10 +1069,10 @@ validate_and_copy_buf(unsigned int offset, unsigned int buffer_length,
        return 0;
 }
 
-int
-SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon,
-               u64 persistent_fid, u64 volatile_fid,
-               struct smb2_file_all_info *data)
+static int
+query_info(const unsigned int xid, struct cifs_tcon *tcon,
+          u64 persistent_fid, u64 volatile_fid, u8 info_class,
+          size_t output_len, size_t min_len, void *data)
 {
        struct smb2_query_info_req *req;
        struct smb2_query_info_rsp *rsp = NULL;
@@ -1044,14 +1094,13 @@ SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon,
                return rc;
 
        req->InfoType = SMB2_O_INFO_FILE;
-       req->FileInfoClass = FILE_ALL_INFORMATION;
+       req->FileInfoClass = info_class;
        req->PersistentFileId = persistent_fid;
        req->VolatileFileId = volatile_fid;
        /* 4 for rfc1002 length field and 1 for Buffer */
        req->InputBufferOffset =
                cpu_to_le16(sizeof(struct smb2_query_info_req) - 1 - 4);
-       req->OutputBufferLength =
-               cpu_to_le32(sizeof(struct smb2_file_all_info) + MAX_NAME * 2);
+       req->OutputBufferLength = cpu_to_le32(output_len);
 
        iov[0].iov_base = (char *)req;
        /* 4 for rfc1002 length field */
@@ -1067,14 +1116,34 @@ SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon,
 
        rc = validate_and_copy_buf(le16_to_cpu(rsp->OutputBufferOffset),
                                   le32_to_cpu(rsp->OutputBufferLength),
-                                  &rsp->hdr, sizeof(struct smb2_file_all_info),
-                                  (char *)data);
+                                  &rsp->hdr, min_len, data);
 
 qinf_exit:
        free_rsp_buf(resp_buftype, rsp);
        return rc;
 }
 
+int
+SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon,
+               u64 persistent_fid, u64 volatile_fid,
+               struct smb2_file_all_info *data)
+{
+       return query_info(xid, tcon, persistent_fid, volatile_fid,
+                         FILE_ALL_INFORMATION,
+                         sizeof(struct smb2_file_all_info) + MAX_NAME * 2,
+                         sizeof(struct smb2_file_all_info), data);
+}
+
+int
+SMB2_get_srv_num(const unsigned int xid, struct cifs_tcon *tcon,
+                u64 persistent_fid, u64 volatile_fid, __le64 *uniqueid)
+{
+       return query_info(xid, tcon, persistent_fid, volatile_fid,
+                         FILE_INTERNAL_INFORMATION,
+                         sizeof(struct smb2_file_internal_info),
+                         sizeof(struct smb2_file_internal_info), uniqueid);
+}
+
 /*
  * This is a no-op for now. We're not really interested in the reply, but
  * rather in the fact that the server sent one and that server->lstrp
@@ -1123,3 +1192,752 @@ SMB2_echo(struct TCP_Server_Info *server)
        cifs_small_buf_release(req);
        return rc;
 }
+
+int
+SMB2_flush(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
+          u64 volatile_fid)
+{
+       struct smb2_flush_req *req;
+       struct TCP_Server_Info *server;
+       struct cifs_ses *ses = tcon->ses;
+       struct kvec iov[1];
+       int resp_buftype;
+       int rc = 0;
+
+       cFYI(1, "Flush");
+
+       if (ses && (ses->server))
+               server = ses->server;
+       else
+               return -EIO;
+
+       rc = small_smb2_init(SMB2_FLUSH, tcon, (void **) &req);
+       if (rc)
+               return rc;
+
+       req->PersistentFileId = persistent_fid;
+       req->VolatileFileId = volatile_fid;
+
+       iov[0].iov_base = (char *)req;
+       /* 4 for rfc1002 length field */
+       iov[0].iov_len = get_rfc1002_length(req) + 4;
+
+       rc = SendReceive2(xid, ses, iov, 1, &resp_buftype, 0);
+
+       if ((rc != 0) && tcon)
+               cifs_stats_fail_inc(tcon, SMB2_FLUSH_HE);
+
+       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)) {
+                       int rc;
+
+                       rc = smb2_verify_signature2(rdata->iov, rdata->nr_iov,
+                                                   server);
+                       if (rc)
+                               cERROR(1, "SMB signature verification returned "
+                                      "error = %d", rc);
+               }
+               /* 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;
+}
+
+int
+SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms,
+         unsigned int *nbytes, char **buf, int *buf_type)
+{
+       int resp_buftype, rc = -EACCES;
+       struct smb2_read_rsp *rsp = NULL;
+       struct kvec iov[1];
+
+       *nbytes = 0;
+       rc = smb2_new_read_req(iov, io_parms, 0, 0);
+       if (rc)
+               return rc;
+
+       rc = SendReceive2(xid, io_parms->tcon->ses, iov, 1,
+                         &resp_buftype, CIFS_LOG_ERROR);
+
+       rsp = (struct smb2_read_rsp *)iov[0].iov_base;
+
+       if (rsp->hdr.Status == STATUS_END_OF_FILE) {
+               free_rsp_buf(resp_buftype, iov[0].iov_base);
+               return 0;
+       }
+
+       if (rc) {
+               cifs_stats_fail_inc(io_parms->tcon, SMB2_READ_HE);
+               cERROR(1, "Send error in read = %d", rc);
+       } else {
+               *nbytes = le32_to_cpu(rsp->DataLength);
+               if ((*nbytes > CIFS_MAX_MSGSIZE) ||
+                   (*nbytes > io_parms->length)) {
+                       cFYI(1, "bad length %d for count %d", *nbytes,
+                               io_parms->length);
+                       rc = -EIO;
+                       *nbytes = 0;
+               }
+       }
+
+       if (*buf) {
+               memcpy(*buf, (char *)rsp->hdr.ProtocolId + rsp->DataOffset,
+                      *nbytes);
+               free_rsp_buf(resp_buftype, iov[0].iov_base);
+       } else if (resp_buftype != CIFS_NO_BUFFER) {
+               *buf = iov[0].iov_base;
+               if (resp_buftype == CIFS_SMALL_BUFFER)
+                       *buf_type = CIFS_SMALL_BUFFER;
+               else if (resp_buftype == CIFS_LARGE_BUFFER)
+                       *buf_type = CIFS_LARGE_BUFFER;
+       }
+       return rc;
+}
+
+/*
+ * Check the mid_state and signature on received buffer (if any), and queue the
+ * workqueue completion task.
+ */
+static void
+smb2_writev_callback(struct mid_q_entry *mid)
+{
+       struct cifs_writedata *wdata = mid->callback_data;
+       struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
+       unsigned int written;
+       struct smb2_write_rsp *rsp = (struct smb2_write_rsp *)mid->resp_buf;
+       unsigned int credits_received = 1;
+
+       switch (mid->mid_state) {
+       case MID_RESPONSE_RECEIVED:
+               credits_received = le16_to_cpu(rsp->hdr.CreditRequest);
+               wdata->result = smb2_check_receive(mid, tcon->ses->server, 0);
+               if (wdata->result != 0)
+                       break;
+
+               written = le32_to_cpu(rsp->DataLength);
+               /*
+                * Mask off high 16 bits when bytes written as returned
+                * by the server is greater than bytes requested by the
+                * client. OS/2 servers are known to set incorrect
+                * CountHigh values.
+                */
+               if (written > wdata->bytes)
+                       written &= 0xFFFF;
+
+               if (written < wdata->bytes)
+                       wdata->result = -ENOSPC;
+               else
+                       wdata->bytes = written;
+               break;
+       case MID_REQUEST_SUBMITTED:
+       case MID_RETRY_NEEDED:
+               wdata->result = -EAGAIN;
+               break;
+       default:
+               wdata->result = -EIO;
+               break;
+       }
+
+       if (wdata->result)
+               cifs_stats_fail_inc(tcon, SMB2_WRITE_HE);
+
+       queue_work(cifsiod_wq, &wdata->work);
+       DeleteMidQEntry(mid);
+       add_credits(tcon->ses->server, credits_received, 0);
+}
+
+/* smb2_async_writev - send an async write, and set up mid to handle result */
+int
+smb2_async_writev(struct cifs_writedata *wdata)
+{
+       int i, rc = -EACCES;
+       struct smb2_write_req *req = NULL;
+       struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
+       struct kvec *iov = NULL;
+
+       rc = small_smb2_init(SMB2_WRITE, tcon, (void **) &req);
+       if (rc)
+               goto async_writev_out;
+
+       /* 1 iov per page + 1 for header */
+       iov = kzalloc((wdata->nr_pages + 1) * sizeof(*iov), GFP_NOFS);
+       if (iov == NULL) {
+               rc = -ENOMEM;
+               goto async_writev_out;
+       }
+
+       req->hdr.ProcessId = cpu_to_le32(wdata->cfile->pid);
+
+       req->PersistentFileId = wdata->cfile->fid.persistent_fid;
+       req->VolatileFileId = wdata->cfile->fid.volatile_fid;
+       req->WriteChannelInfoOffset = 0;
+       req->WriteChannelInfoLength = 0;
+       req->Channel = 0;
+       req->Offset = cpu_to_le64(wdata->offset);
+       /* 4 for rfc1002 length field */
+       req->DataOffset = cpu_to_le16(
+                               offsetof(struct smb2_write_req, Buffer) - 4);
+       req->RemainingBytes = 0;
+
+       /* 4 for rfc1002 length field and 1 for Buffer */
+       iov[0].iov_len = get_rfc1002_length(req) + 4 - 1;
+       iov[0].iov_base = (char *)req;
+
+       /*
+        * This function should marshal up the page array into the kvec
+        * array, reserving [0] for the header. It should kmap the pages
+        * and set the iov_len properly for each one. It may also set
+        * wdata->bytes too.
+        */
+       cifs_kmap_lock();
+       wdata->marshal_iov(iov, wdata);
+       cifs_kmap_unlock();
+
+       cFYI(1, "async write at %llu %u bytes", wdata->offset, wdata->bytes);
+
+       req->Length = cpu_to_le32(wdata->bytes);
+
+       inc_rfc1001_len(&req->hdr, wdata->bytes - 1 /* Buffer */);
+
+       kref_get(&wdata->refcount);
+       rc = cifs_call_async(tcon->ses->server, iov, wdata->nr_pages + 1,
+                            NULL, smb2_writev_callback, wdata, 0);
+
+       if (rc)
+               kref_put(&wdata->refcount, cifs_writedata_release);
+
+       /* send is done, unmap pages */
+       for (i = 0; i < wdata->nr_pages; i++)
+               kunmap(wdata->pages[i]);
+
+async_writev_out:
+       cifs_small_buf_release(req);
+       kfree(iov);
+       return rc;
+}
+
+/*
+ * SMB2_write function gets iov pointer to kvec array with n_vec as a length.
+ * The length field from io_parms must be at least 1 and indicates a number of
+ * elements with data to write that begins with position 1 in iov array. All
+ * data length is specified by count.
+ */
+int
+SMB2_write(const unsigned int xid, struct cifs_io_parms *io_parms,
+          unsigned int *nbytes, struct kvec *iov, int n_vec)
+{
+       int rc = 0;
+       struct smb2_write_req *req = NULL;
+       struct smb2_write_rsp *rsp = NULL;
+       int resp_buftype;
+       *nbytes = 0;
+
+       if (n_vec < 1)
+               return rc;
+
+       rc = small_smb2_init(SMB2_WRITE, 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->WriteChannelInfoOffset = 0;
+       req->WriteChannelInfoLength = 0;
+       req->Channel = 0;
+       req->Length = cpu_to_le32(io_parms->length);
+       req->Offset = cpu_to_le64(io_parms->offset);
+       /* 4 for rfc1002 length field */
+       req->DataOffset = cpu_to_le16(
+                               offsetof(struct smb2_write_req, Buffer) - 4);
+       req->RemainingBytes = 0;
+
+       iov[0].iov_base = (char *)req;
+       /* 4 for rfc1002 length field and 1 for Buffer */
+       iov[0].iov_len = get_rfc1002_length(req) + 4 - 1;
+
+       /* length of entire message including data to be written */
+       inc_rfc1001_len(req, io_parms->length - 1 /* Buffer */);
+
+       rc = SendReceive2(xid, io_parms->tcon->ses, iov, n_vec + 1,
+                         &resp_buftype, 0);
+
+       if (rc) {
+               cifs_stats_fail_inc(io_parms->tcon, SMB2_WRITE_HE);
+               cERROR(1, "Send error in write = %d", rc);
+       } else {
+               rsp = (struct smb2_write_rsp *)iov[0].iov_base;
+               *nbytes = le32_to_cpu(rsp->DataLength);
+               free_rsp_buf(resp_buftype, rsp);
+       }
+       return rc;
+}
+
+static unsigned int
+num_entries(char *bufstart, char *end_of_buf, char **lastentry, size_t size)
+{
+       int len;
+       unsigned int entrycount = 0;
+       unsigned int next_offset = 0;
+       FILE_DIRECTORY_INFO *entryptr;
+
+       if (bufstart == NULL)
+               return 0;
+
+       entryptr = (FILE_DIRECTORY_INFO *)bufstart;
+
+       while (1) {
+               entryptr = (FILE_DIRECTORY_INFO *)
+                                       ((char *)entryptr + next_offset);
+
+               if ((char *)entryptr + size > end_of_buf) {
+                       cERROR(1, "malformed search entry would overflow");
+                       break;
+               }
+
+               len = le32_to_cpu(entryptr->FileNameLength);
+               if ((char *)entryptr + len + size > end_of_buf) {
+                       cERROR(1, "directory entry name would overflow frame "
+                                 "end of buf %p", end_of_buf);
+                       break;
+               }
+
+               *lastentry = (char *)entryptr;
+               entrycount++;
+
+               next_offset = le32_to_cpu(entryptr->NextEntryOffset);
+               if (!next_offset)
+                       break;
+       }
+
+       return entrycount;
+}
+
+/*
+ * Readdir/FindFirst
+ */
+int
+SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon,
+                    u64 persistent_fid, u64 volatile_fid, int index,
+                    struct cifs_search_info *srch_inf)
+{
+       struct smb2_query_directory_req *req;
+       struct smb2_query_directory_rsp *rsp = NULL;
+       struct kvec iov[2];
+       int rc = 0;
+       int len;
+       int resp_buftype;
+       unsigned char *bufptr;
+       struct TCP_Server_Info *server;
+       struct cifs_ses *ses = tcon->ses;
+       __le16 asteriks = cpu_to_le16('*');
+       char *end_of_smb;
+       unsigned int output_size = CIFSMaxBufSize;
+       size_t info_buf_size;
+
+       if (ses && (ses->server))
+               server = ses->server;
+       else
+               return -EIO;
+
+       rc = small_smb2_init(SMB2_QUERY_DIRECTORY, tcon, (void **) &req);
+       if (rc)
+               return rc;
+
+       switch (srch_inf->info_level) {
+       case SMB_FIND_FILE_DIRECTORY_INFO:
+               req->FileInformationClass = FILE_DIRECTORY_INFORMATION;
+               info_buf_size = sizeof(FILE_DIRECTORY_INFO) - 1;
+               break;
+       case SMB_FIND_FILE_ID_FULL_DIR_INFO:
+               req->FileInformationClass = FILEID_FULL_DIRECTORY_INFORMATION;
+               info_buf_size = sizeof(SEARCH_ID_FULL_DIR_INFO) - 1;
+               break;
+       default:
+               cERROR(1, "info level %u isn't supported",
+                      srch_inf->info_level);
+               rc = -EINVAL;
+               goto qdir_exit;
+       }
+
+       req->FileIndex = cpu_to_le32(index);
+       req->PersistentFileId = persistent_fid;
+       req->VolatileFileId = volatile_fid;
+
+       len = 0x2;
+       bufptr = req->Buffer;
+       memcpy(bufptr, &asteriks, len);
+
+       req->FileNameOffset =
+               cpu_to_le16(sizeof(struct smb2_query_directory_req) - 1 - 4);
+       req->FileNameLength = cpu_to_le16(len);
+       /*
+        * BB could be 30 bytes or so longer if we used SMB2 specific
+        * buffer lengths, but this is safe and close enough.
+        */
+       output_size = min_t(unsigned int, output_size, server->maxBuf);
+       output_size = min_t(unsigned int, output_size, 2 << 15);
+       req->OutputBufferLength = cpu_to_le32(output_size);
+
+       iov[0].iov_base = (char *)req;
+       /* 4 for RFC1001 length and 1 for Buffer */
+       iov[0].iov_len = get_rfc1002_length(req) + 4 - 1;
+
+       iov[1].iov_base = (char *)(req->Buffer);
+       iov[1].iov_len = len;
+
+       inc_rfc1001_len(req, len - 1 /* Buffer */);
+
+       rc = SendReceive2(xid, ses, iov, 2, &resp_buftype, 0);
+       if (rc) {
+               cifs_stats_fail_inc(tcon, SMB2_QUERY_DIRECTORY_HE);
+               goto qdir_exit;
+       }
+       rsp = (struct smb2_query_directory_rsp *)iov[0].iov_base;
+
+       rc = validate_buf(le16_to_cpu(rsp->OutputBufferOffset),
+                         le32_to_cpu(rsp->OutputBufferLength), &rsp->hdr,
+                         info_buf_size);
+       if (rc)
+               goto qdir_exit;
+
+       srch_inf->unicode = true;
+
+       if (srch_inf->ntwrk_buf_start) {
+               if (srch_inf->smallBuf)
+                       cifs_small_buf_release(srch_inf->ntwrk_buf_start);
+               else
+                       cifs_buf_release(srch_inf->ntwrk_buf_start);
+       }
+       srch_inf->ntwrk_buf_start = (char *)rsp;
+       srch_inf->srch_entries_start = srch_inf->last_entry = 4 /* rfclen */ +
+               (char *)&rsp->hdr + le16_to_cpu(rsp->OutputBufferOffset);
+       /* 4 for rfc1002 length field */
+       end_of_smb = get_rfc1002_length(rsp) + 4 + (char *)&rsp->hdr;
+       srch_inf->entries_in_buffer =
+                       num_entries(srch_inf->srch_entries_start, end_of_smb,
+                                   &srch_inf->last_entry, info_buf_size);
+       srch_inf->index_of_last_entry += srch_inf->entries_in_buffer;
+       cFYI(1, "num entries %d last_index %lld srch start %p srch end %p",
+               srch_inf->entries_in_buffer, srch_inf->index_of_last_entry,
+               srch_inf->srch_entries_start, srch_inf->last_entry);
+       if (resp_buftype == CIFS_LARGE_BUFFER)
+               srch_inf->smallBuf = false;
+       else if (resp_buftype == CIFS_SMALL_BUFFER)
+               srch_inf->smallBuf = true;
+       else
+               cERROR(1, "illegal search buffer type");
+
+       if (rsp->hdr.Status == STATUS_NO_MORE_FILES)
+               srch_inf->endOfSearch = 1;
+       else
+               srch_inf->endOfSearch = 0;
+
+       return rc;
+
+qdir_exit:
+       free_rsp_buf(resp_buftype, rsp);
+       return rc;
+}
+
+static int
+send_set_info(const unsigned int xid, struct cifs_tcon *tcon,
+              u64 persistent_fid, u64 volatile_fid, u32 pid, int info_class,
+              unsigned int num, void **data, unsigned int *size)
+{
+       struct smb2_set_info_req *req;
+       struct smb2_set_info_rsp *rsp = NULL;
+       struct kvec *iov;
+       int rc = 0;
+       int resp_buftype;
+       unsigned int i;
+       struct TCP_Server_Info *server;
+       struct cifs_ses *ses = tcon->ses;
+
+       if (ses && (ses->server))
+               server = ses->server;
+       else
+               return -EIO;
+
+       if (!num)
+               return -EINVAL;
+
+       iov = kmalloc(sizeof(struct kvec) * num, GFP_KERNEL);
+       if (!iov)
+               return -ENOMEM;
+
+       rc = small_smb2_init(SMB2_SET_INFO, tcon, (void **) &req);
+       if (rc) {
+               kfree(iov);
+               return rc;
+       }
+
+       req->hdr.ProcessId = cpu_to_le32(pid);
+
+       req->InfoType = SMB2_O_INFO_FILE;
+       req->FileInfoClass = info_class;
+       req->PersistentFileId = persistent_fid;
+       req->VolatileFileId = volatile_fid;
+
+       /* 4 for RFC1001 length and 1 for Buffer */
+       req->BufferOffset =
+                       cpu_to_le16(sizeof(struct smb2_set_info_req) - 1 - 4);
+       req->BufferLength = cpu_to_le32(*size);
+
+       inc_rfc1001_len(req, *size - 1 /* Buffer */);
+
+       memcpy(req->Buffer, *data, *size);
+
+       iov[0].iov_base = (char *)req;
+       /* 4 for RFC1001 length */
+       iov[0].iov_len = get_rfc1002_length(req) + 4;
+
+       for (i = 1; i < num; i++) {
+               inc_rfc1001_len(req, size[i]);
+               le32_add_cpu(&req->BufferLength, size[i]);
+               iov[i].iov_base = (char *)data[i];
+               iov[i].iov_len = size[i];
+       }
+
+       rc = SendReceive2(xid, ses, iov, num, &resp_buftype, 0);
+       rsp = (struct smb2_set_info_rsp *)iov[0].iov_base;
+
+       if (rc != 0) {
+               cifs_stats_fail_inc(tcon, SMB2_SET_INFO_HE);
+               goto out;
+       }
+
+       if (rsp == NULL) {
+               rc = -EIO;
+               goto out;
+       }
+
+out:
+       free_rsp_buf(resp_buftype, rsp);
+       kfree(iov);
+       return rc;
+}
+
+int
+SMB2_rename(const unsigned int xid, struct cifs_tcon *tcon,
+           u64 persistent_fid, u64 volatile_fid, __le16 *target_file)
+{
+       struct smb2_file_rename_info info;
+       void **data;
+       unsigned int size[2];
+       int rc;
+       int len = (2 * UniStrnlen((wchar_t *)target_file, PATH_MAX));
+
+       data = kmalloc(sizeof(void *) * 2, GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       info.ReplaceIfExists = 1; /* 1 = replace existing target with new */
+                             /* 0 = fail if target already exists */
+       info.RootDirectory = 0;  /* MBZ for network ops (why does spec say?) */
+       info.FileNameLength = cpu_to_le32(len);
+
+       data[0] = &info;
+       size[0] = sizeof(struct smb2_file_rename_info);
+
+       data[1] = target_file;
+       size[1] = len + 2 /* null */;
+
+       rc = send_set_info(xid, tcon, persistent_fid, volatile_fid,
+                          current->tgid, FILE_RENAME_INFORMATION, 2, data,
+                          size);
+       kfree(data);
+       return rc;
+}
+
+int
+SMB2_set_hardlink(const unsigned int xid, struct cifs_tcon *tcon,
+                 u64 persistent_fid, u64 volatile_fid, __le16 *target_file)
+{
+       struct smb2_file_link_info info;
+       void **data;
+       unsigned int size[2];
+       int rc;
+       int len = (2 * UniStrnlen((wchar_t *)target_file, PATH_MAX));
+
+       data = kmalloc(sizeof(void *) * 2, GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       info.ReplaceIfExists = 0; /* 1 = replace existing link with new */
+                             /* 0 = fail if link already exists */
+       info.RootDirectory = 0;  /* MBZ for network ops (why does spec say?) */
+       info.FileNameLength = cpu_to_le32(len);
+
+       data[0] = &info;
+       size[0] = sizeof(struct smb2_file_link_info);
+
+       data[1] = target_file;
+       size[1] = len + 2 /* null */;
+
+       rc = send_set_info(xid, tcon, persistent_fid, volatile_fid,
+                          current->tgid, FILE_LINK_INFORMATION, 2, data, size);
+       kfree(data);
+       return rc;
+}
+
+int
+SMB2_set_eof(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
+            u64 volatile_fid, u32 pid, __le64 *eof)
+{
+       struct smb2_file_eof_info info;
+       void *data;
+       unsigned int size;
+
+       info.EndOfFile = *eof;
+
+       data = &info;
+       size = sizeof(struct smb2_file_eof_info);
+
+       return send_set_info(xid, tcon, persistent_fid, volatile_fid, pid,
+                            FILE_END_OF_FILE_INFORMATION, 1, &data, &size);
+}
+
+int
+SMB2_set_info(const unsigned int xid, struct cifs_tcon *tcon,
+             u64 persistent_fid, u64 volatile_fid, FILE_BASIC_INFO *buf)
+{
+       unsigned int size;
+       size = sizeof(FILE_BASIC_INFO);
+       return send_set_info(xid, tcon, persistent_fid, volatile_fid,
+                            current->tgid, FILE_BASIC_INFORMATION, 1,
+                            (void **)&buf, &size);
+}