netfilter: xtables: constify args in compat copying functions
[safe/jmp/linux-2.6] / net / 9p / client.c
index 90ee9ef..8af95b2 100644 (file)
@@ -35,6 +35,7 @@
 #include <linux/parser.h>
 #include <net/9p/client.h>
 #include <net/9p/transport.h>
+#include "protocol.h"
 
 /*
   * Client Option Parsing (code inspired by NFS code)
@@ -55,13 +56,13 @@ static const match_table_t tokens = {
        {Opt_err, NULL},
 };
 
-static int
-p9_client_rpc(struct p9_client *c, struct p9_fcall *tc, struct p9_fcall **rc);
+static struct p9_req_t *
+p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 
 /**
- * v9fs_parse_options - parse mount options into session structure
- * @options: options string passed from mount
- * @v9ses: existing v9fs session information
+ * parse_options - parse mount options into client structure
+ * @opts: options string passed from mount
+ * @clnt: existing v9fs client information
  *
  * Return 0 upon success, -ERRNO upon failure
  */
@@ -116,9 +117,6 @@ static int parse_opts(char *opts, struct p9_client *clnt)
                }
        }
 
-       if (!clnt->trans_mod)
-               clnt->trans_mod = v9fs_get_default_trans();
-
        kfree(options);
        return ret;
 }
@@ -138,10 +136,11 @@ static int parse_opts(char *opts, struct p9_client *clnt)
  *
  */
 
-struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
+static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
 {
        unsigned long flags;
        int row, col;
+       struct p9_req_t *req;
 
        /* This looks up the original request by tag so we know which
         * buffer to read the data into */
@@ -157,19 +156,12 @@ struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
 
                        if (!c->reqs[row]) {
                                printk(KERN_ERR "Couldn't grow tag array\n");
-                               BUG();
+                               spin_unlock_irqrestore(&c->lock, flags);
+                               return ERR_PTR(-ENOMEM);
                        }
                        for (col = 0; col < P9_ROW_MAXTAG; col++) {
                                c->reqs[row][col].status = REQ_STATUS_IDLE;
-                               c->reqs[row][col].flush_tag = P9_NOTAG;
-                               c->reqs[row][col].wq = kmalloc(
-                                       sizeof(wait_queue_head_t), GFP_ATOMIC);
-                               if (!c->reqs[row][col].wq) {
-                                       printk(KERN_ERR
-                                               "Couldn't grow tag array\n");
-                                       BUG();
-                               }
-                               init_waitqueue_head(c->reqs[row][col].wq);
+                               c->reqs[row][col].tc = NULL;
                        }
                        c->max_tag += P9_ROW_MAXTAG;
                }
@@ -178,12 +170,41 @@ struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
        row = tag / P9_ROW_MAXTAG;
        col = tag % P9_ROW_MAXTAG;
 
-       c->reqs[row][col].status = REQ_STATUS_ALLOC;
-       c->reqs[row][col].flush_tag = P9_NOTAG;
+       req = &c->reqs[row][col];
+       if (!req->tc) {
+               req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
+               if (!req->wq) {
+                       printk(KERN_ERR "Couldn't grow tag array\n");
+                       return ERR_PTR(-ENOMEM);
+               }
+               init_waitqueue_head(req->wq);
+               req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
+                                                               GFP_KERNEL);
+               req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
+                                                               GFP_KERNEL);
+               if ((!req->tc) || (!req->rc)) {
+                       printk(KERN_ERR "Couldn't grow tag array\n");
+                       kfree(req->tc);
+                       kfree(req->rc);
+                       kfree(req->wq);
+                       req->tc = req->rc = NULL;
+                       req->wq = NULL;
+                       return ERR_PTR(-ENOMEM);
+               }
+               req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
+               req->tc->capacity = c->msize;
+               req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
+               req->rc->capacity = c->msize;
+       }
+
+       p9pdu_reset(req->tc);
+       p9pdu_reset(req->rc);
+
+       req->tc->tag = tag-1;
+       req->status = REQ_STATUS_ALLOC;
 
        return &c->reqs[row][col];
 }
-EXPORT_SYMBOL(p9_tag_alloc);
 
 /**
  * p9_tag_lookup - lookup a request by tag
@@ -211,7 +232,7 @@ EXPORT_SYMBOL(p9_tag_lookup);
 
 /**
  * p9_tag_init - setup tags structure and contents
- * @tags: tags structure from the client struct
+ * @c:  v9fs client struct
  *
  * This initializes the tags structure for each client instance.
  *
@@ -237,7 +258,7 @@ error:
 
 /**
  * p9_tag_cleanup - cleans up tags structure and reclaims resources
- * @tags: tags structure from the client struct
+ * @c:  v9fs client struct
  *
  * This frees resources associated with the tags structure
  *
@@ -264,129 +285,206 @@ static void p9_tag_cleanup(struct p9_client *c)
 
        /* free requests associated with tags */
        for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
-               for (col = 0; col < P9_ROW_MAXTAG; col++)
+               for (col = 0; col < P9_ROW_MAXTAG; col++) {
                        kfree(c->reqs[row][col].wq);
+                       kfree(c->reqs[row][col].tc);
+                       kfree(c->reqs[row][col].rc);
+               }
                kfree(c->reqs[row]);
        }
        c->max_tag = 0;
 }
 
 /**
- * p9_client_flush - flush (cancel) a request
+ * p9_free_req - free a request and clean-up as necessary
  * c: client state
- * req: request to cancel
+ * r: request to release
  *
- * This sents a flush for a particular requests and links
- * the flush request to the original request.  The current
- * code only supports a single flush request although the protocol
- * allows for multiple flush requests to be sent for a single request.
+ */
+
+static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
+{
+       int tag = r->tc->tag;
+       P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
+
+       r->status = REQ_STATUS_IDLE;
+       if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
+               p9_idpool_put(tag, c->tagpool);
+}
+
+/**
+ * p9_client_cb - call back from transport to client
+ * c: client state
+ * req: request received
  *
  */
+void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
+{
+       P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
+       wake_up(req->wq);
+       P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
+}
+EXPORT_SYMBOL(p9_client_cb);
 
-static int p9_client_flush(struct p9_client *c, struct p9_req_t *req)
+/**
+ * p9_parse_header - parse header arguments out of a packet
+ * @pdu: packet to parse
+ * @size: size of packet
+ * @type: type of request
+ * @tag: tag of packet
+ * @rewind: set if we need to rewind offset afterwards
+ */
+
+int
+p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
+                                                               int rewind)
 {
-       struct p9_fcall *tc, *rc = NULL;
+       int8_t r_type;
+       int16_t r_tag;
+       int32_t r_size;
+       int offset = pdu->offset;
        int err;
 
-       P9_DPRINTK(P9_DEBUG_9P, "client %p tag %d\n", c, req->tc->tag);
+       pdu->offset = 0;
+       if (pdu->size == 0)
+               pdu->size = 7;
 
-       tc = p9_create_tflush(req->tc->tag);
-       if (IS_ERR(tc))
-               return PTR_ERR(tc);
+       err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
+       if (err)
+               goto rewind_and_exit;
+
+       pdu->size = r_size;
+       pdu->id = r_type;
+       pdu->tag = r_tag;
 
-       err = p9_client_rpc(c, tc, &rc);
+       P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
+                                                       pdu->id, pdu->tag);
 
-       /* we don't free anything here because RPC isn't complete */
+       if (type)
+               *type = r_type;
+       if (tag)
+               *tag = r_tag;
+       if (size)
+               *size = r_size;
 
+
+rewind_and_exit:
+       if (rewind)
+               pdu->offset = offset;
        return err;
 }
+EXPORT_SYMBOL(p9_parse_header);
 
 /**
- * p9_free_req - free a request and clean-up as necessary
- * c: client state
- * r: request to release
+ * p9_check_errors - check 9p packet for error return and process it
+ * @c: current client instance
+ * @req: request to parse and check for error conditions
  *
+ * returns error code if one is discovered, otherwise returns 0
+ *
+ * this will have to be more complicated if we have multiple
+ * error packet types
  */
 
-void p9_free_req(struct p9_client *c, struct p9_req_t *r)
+static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 {
-       r->flush_tag = P9_NOTAG;
-       r->status = REQ_STATUS_IDLE;
-       if (r->tc->tag != P9_NOTAG && p9_idpool_check(r->tc->tag, c->tagpool))
-               p9_idpool_put(r->tc->tag, c->tagpool);
+       int8_t type;
+       int err;
 
-       /* if this was a flush request we have to free response fcall */
-       if (r->tc->id == P9_TFLUSH) {
-               kfree(r->tc);
-               kfree(r->rc);
+       err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
+       if (err) {
+               P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
+               return err;
        }
+
+       if (type == P9_RERROR) {
+               int ecode;
+               char *ename;
+
+               err = p9pdu_readf(req->rc, c->dotu, "s?d", &ename, &ecode);
+               if (err) {
+                       P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
+                                                                       err);
+                       return err;
+               }
+
+               if (c->dotu)
+                       err = -ecode;
+
+               if (!err || !IS_ERR_VALUE(err))
+                       err = p9_errstr2errno(ename, strlen(ename));
+
+               P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
+
+               kfree(ename);
+       } else
+               err = 0;
+
+       return err;
 }
 
 /**
- * p9_client_cb - call back from transport to client
- * c: client state
- * req: request received
+ * p9_client_flush - flush (cancel) a request
+ * @c: client state
+ * @oldreq: request to cancel
+ *
+ * This sents a flush for a particular requests and links
+ * the flush request to the original request.  The current
+ * code only supports a single flush request although the protocol
+ * allows for multiple flush requests to be sent for a single request.
  *
  */
-void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
+
+static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 {
-       struct p9_req_t *other_req;
-       unsigned long flags;
+       struct p9_req_t *req;
+       int16_t oldtag;
+       int err;
 
-       P9_DPRINTK(P9_DEBUG_MUX, ": %d\n", req->tc->tag);
+       err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
+       if (err)
+               return err;
 
-       if (req->status == REQ_STATUS_ERROR)
-               wake_up(req->wq);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 
-       if (req->tc->id == P9_TFLUSH) { /* flush receive path */
-               P9_DPRINTK(P9_DEBUG_MUX, "flush: %d\n", req->tc->tag);
-               spin_lock_irqsave(&c->lock, flags);
-               other_req = p9_tag_lookup(c, req->tc->params.tflush.oldtag);
-               if (other_req->flush_tag != req->tc->tag) /* stale flush */
-                       spin_unlock_irqrestore(&c->lock, flags);
-               else {
-                       BUG_ON(other_req->status != REQ_STATUS_FLSH);
-                       other_req->status = REQ_STATUS_FLSHD;
-                       spin_unlock_irqrestore(&c->lock, flags);
-                       wake_up(other_req->wq);
-               }
-               p9_free_req(c, req);
-       } else {                                /* normal receive path */
-               P9_DPRINTK(P9_DEBUG_MUX, "normal: %d\n", req->tc->tag);
-               spin_lock_irqsave(&c->lock, flags);
-               if (req->status != REQ_STATUS_FLSHD)
-                       req->status = REQ_STATUS_RCVD;
-               req->flush_tag = P9_NOTAG;
-               spin_unlock_irqrestore(&c->lock, flags);
-               wake_up(req->wq);
-               P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
-       }
+       req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
+       if (IS_ERR(req))
+               return PTR_ERR(req);
+
+
+       /* if we haven't received a response for oldreq,
+          remove it from the list. */
+       spin_lock(&c->lock);
+       if (oldreq->status == REQ_STATUS_FLSH)
+               list_del(&oldreq->req_list);
+       spin_unlock(&c->lock);
+
+       p9_free_req(c, req);
+       return 0;
 }
-EXPORT_SYMBOL(p9_client_cb);
 
 /**
  * p9_client_rpc - issue a request and wait for a response
  * @c: client session
- * @tc: &p9_fcall request to transmit
- * @rc: &p9_fcall to put reponse into
+ * @type: type of request
+ * @fmt: protocol format string (see protocol.c)
  *
- * Returns 0 on success, error code on failure
+ * Returns request structure (which client must free using p9_free_req)
  */
 
-static int
-p9_client_rpc(struct p9_client *c, struct p9_fcall *tc, struct p9_fcall **rc)
+static struct p9_req_t *
+p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 {
-       int tag, err, size;
-       char *rdata;
+       va_list ap;
+       int tag, err;
        struct p9_req_t *req;
        unsigned long flags;
        int sigpending;
-       int flushed = 0;
 
-       P9_DPRINTK(P9_DEBUG_9P, "client %p tc %p rc %p\n", c, tc, rc);
+       P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 
        if (c->status != Connected)
-               return -EIO;
+               return ERR_PTR(-EIO);
 
        if (signal_pending(current)) {
                sigpending = 1;
@@ -395,50 +493,22 @@ p9_client_rpc(struct p9_client *c, struct p9_fcall *tc, struct p9_fcall **rc)
                sigpending = 0;
 
        tag = P9_NOTAG;
-       if (tc->id != P9_TVERSION) {
+       if (type != P9_TVERSION) {
                tag = p9_idpool_get(c->tagpool);
                if (tag < 0)
-                       return -ENOMEM;
+                       return ERR_PTR(-ENOMEM);
        }
 
        req = p9_tag_alloc(c, tag);
+       if (IS_ERR(req))
+               return req;
 
-       /* if this is a flush request, backlink flush request now to
-        * avoid race conditions later. */
-       if (tc->id == P9_TFLUSH) {
-               struct p9_req_t *other_req =
-                               p9_tag_lookup(c, tc->params.tflush.oldtag);
-               if (other_req->status == REQ_STATUS_FLSH)
-                       other_req->flush_tag = tag;
-       }
-
-       p9_set_tag(tc, tag);
-
-       /*
-        * if client passed in a pre-allocated response fcall struct
-        * then we just use that, otherwise we allocate one.
-        */
-
-       if (rc == NULL)
-               req->rc = NULL;
-       else
-               req->rc = *rc;
-       if (req->rc == NULL) {
-               req->rc = kmalloc(sizeof(struct p9_fcall) + c->msize,
-                                                               GFP_KERNEL);
-               if (!req->rc) {
-                       err = -ENOMEM;
-                       p9_idpool_put(tag, c->tagpool);
-                       p9_free_req(c, req);
-                       goto reterr;
-               }
-               *rc = req->rc;
-       }
-
-       rdata = (char *)req->rc+sizeof(struct p9_fcall);
-
-       req->tc = tc;
-       P9_DPRINTK(P9_DEBUG_9P, "request: tc: %p rc: %p\n", req->tc, req->rc);
+       /* marshall the data */
+       p9pdu_prepare(req->tc, tag, type);
+       va_start(ap, fmt);
+       err = p9pdu_vwritef(req->tc, c->dotu, fmt, ap);
+       va_end(ap);
+       p9pdu_finalize(req->tc);
 
        err = c->trans_mod->request(c, req);
        if (err < 0) {
@@ -446,42 +516,28 @@ p9_client_rpc(struct p9_client *c, struct p9_fcall *tc, struct p9_fcall **rc)
                goto reterr;
        }
 
-       /* if it was a flush we just transmitted, return our tag */
-       if (tc->id == P9_TFLUSH)
-               return 0;
-again:
-       P9_DPRINTK(P9_DEBUG_9P, "wait %p tag: %d\n", req->wq, tag);
+       P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
        err = wait_event_interruptible(*req->wq,
                                                req->status >= REQ_STATUS_RCVD);
-       P9_DPRINTK(P9_DEBUG_9P, "wait %p tag: %d returned %d (flushed=%d)\n",
-                                               req->wq, tag, err, flushed);
+       P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
+                                               req->wq, tag, err);
 
        if (req->status == REQ_STATUS_ERROR) {
-               P9_DPRINTK(P9_DEBUG_9P, "req_status error %d\n", req->t_err);
+               P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
                err = req->t_err;
-       } else if (err == -ERESTARTSYS && flushed) {
-               P9_DPRINTK(P9_DEBUG_9P, "flushed - going again\n");
-               goto again;
-       } else if (req->status == REQ_STATUS_FLSHD) {
-               P9_DPRINTK(P9_DEBUG_9P, "flushed - erestartsys\n");
-               err = -ERESTARTSYS;
        }
 
-       if ((err == -ERESTARTSYS) && (c->status == Connected) && (!flushed)) {
-               P9_DPRINTK(P9_DEBUG_9P, "flushing\n");
-               spin_lock_irqsave(&c->lock, flags);
-               if (req->status == REQ_STATUS_SENT)
-                       req->status = REQ_STATUS_FLSH;
-               spin_unlock_irqrestore(&c->lock, flags);
+       if ((err == -ERESTARTSYS) && (c->status == Connected)) {
+               P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
                sigpending = 1;
-               flushed = 1;
                clear_thread_flag(TIF_SIGPENDING);
 
-               if (c->trans_mod->cancel(c, req)) {
-                       err = p9_client_flush(c, req);
-                       if (err == 0)
-                               goto again;
-               }
+               if (c->trans_mod->cancel(c, req))
+                       p9_client_flush(c, req);
+
+               /* if we received the response anyway, don't signal error */
+               if (req->status == REQ_STATUS_RCVD)
+                       err = 0;
        }
 
        if (sigpending) {
@@ -493,110 +549,116 @@ again:
        if (err < 0)
                goto reterr;
 
-       size = le32_to_cpu(*(__le32 *) rdata);
-
-       err = p9_deserialize_fcall(rdata, size, req->rc, c->dotu);
-       if (err < 0) {
-               P9_DPRINTK(P9_DEBUG_9P,
-                       "9p debug: client rpc deserialize returned %d\n", err);
-               goto reterr;
+       err = p9_check_errors(c, req);
+       if (!err) {
+               P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
+               return req;
        }
 
-#ifdef CONFIG_NET_9P_DEBUG
-       if ((p9_debug_level&P9_DEBUG_FCALL) == P9_DEBUG_FCALL) {
-               char buf[150];
-
-               p9_printfcall(buf, sizeof(buf), req->rc, c->dotu);
-               printk(KERN_NOTICE ">>> %p %s\n", c, buf);
-       }
-#endif
-
-       if (req->rc->id == P9_RERROR) {
-               int ecode = req->rc->params.rerror.errno;
-               struct p9_str *ename = &req->rc->params.rerror.error;
-
-               P9_DPRINTK(P9_DEBUG_MUX, "Rerror %.*s\n", ename->len,
-                                                               ename->str);
-
-               if (c->dotu)
-                       err = -ecode;
-
-               if (!err) {
-                       err = p9_errstr2errno(ename->str, ename->len);
-
-                       /* string match failed */
-                       if (!err) {
-                               PRINT_FCALL_ERROR("unknown error", req->rc);
-                               err = -ESERVERFAULT;
-                       }
-               }
-       } else
-               err = 0;
-
 reterr:
+       P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
+                                                                       err);
        p9_free_req(c, req);
-
-       P9_DPRINTK(P9_DEBUG_9P, "returning %d\n", err);
-       return err;
+       return ERR_PTR(err);
 }
 
 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 {
-       int err;
+       int ret;
        struct p9_fid *fid;
+       unsigned long flags;
 
-       P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
+       P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
        fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
        if (!fid)
                return ERR_PTR(-ENOMEM);
 
-       fid->fid = p9_idpool_get(clnt->fidpool);
-       if (fid->fid < 0) {
-               err = -ENOSPC;
+       ret = p9_idpool_get(clnt->fidpool);
+       if (ret < 0) {
+               ret = -ENOSPC;
                goto error;
        }
+       fid->fid = ret;
 
        memset(&fid->qid, 0, sizeof(struct p9_qid));
        fid->mode = -1;
-       fid->rdir_fpos = 0;
-       fid->uid = current->fsuid;
+       fid->uid = current_fsuid();
        fid->clnt = clnt;
-       fid->aux = NULL;
-
-       spin_lock(&clnt->lock);
+       fid->rdir = NULL;
+       spin_lock_irqsave(&clnt->lock, flags);
        list_add(&fid->flist, &clnt->fidlist);
-       spin_unlock(&clnt->lock);
+       spin_unlock_irqrestore(&clnt->lock, flags);
 
        return fid;
 
 error:
        kfree(fid);
-       return ERR_PTR(err);
+       return ERR_PTR(ret);
 }
 
 static void p9_fid_destroy(struct p9_fid *fid)
 {
        struct p9_client *clnt;
+       unsigned long flags;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
+       P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
        clnt = fid->clnt;
        p9_idpool_put(fid->fid, clnt->fidpool);
-       spin_lock(&clnt->lock);
+       spin_lock_irqsave(&clnt->lock, flags);
        list_del(&fid->flist);
-       spin_unlock(&clnt->lock);
+       spin_unlock_irqrestore(&clnt->lock, flags);
+       kfree(fid->rdir);
        kfree(fid);
 }
 
+int p9_client_version(struct p9_client *c)
+{
+       int err = 0;
+       struct p9_req_t *req;
+       char *version;
+       int msize;
+
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d extended %d\n",
+                                                       c->msize, c->dotu);
+       req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize,
+                               c->dotu ? "9P2000.u" : "9P2000");
+       if (IS_ERR(req))
+               return PTR_ERR(req);
+
+       err = p9pdu_readf(req->rc, c->dotu, "ds", &msize, &version);
+       if (err) {
+               P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
+               p9pdu_dump(1, req->rc);
+               goto error;
+       }
+
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
+       if (!memcmp(version, "9P2000.u", 8))
+               c->dotu = 1;
+       else if (!memcmp(version, "9P2000", 6))
+               c->dotu = 0;
+       else {
+               err = -EREMOTEIO;
+               goto error;
+       }
+
+       if (msize < c->msize)
+               c->msize = msize;
+
+error:
+       kfree(version);
+       p9_free_req(c, req);
+
+       return err;
+}
+EXPORT_SYMBOL(p9_client_version);
+
 struct p9_client *p9_client_create(const char *dev_name, char *options)
 {
-       int err, n;
+       int err;
        struct p9_client *clnt;
-       struct p9_fcall *tc, *rc;
-       struct p9_str *version;
 
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
        if (!clnt)
                return ERR_PTR(-ENOMEM);
@@ -618,6 +680,9 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
        if (err < 0)
                goto error;
 
+       if (!clnt->trans_mod)
+               clnt->trans_mod = v9fs_get_default_trans();
+
        if (clnt->trans_mod == NULL) {
                err = -EPROTONOSUPPORT;
                P9_DPRINTK(P9_DEBUG_ERROR,
@@ -625,10 +690,9 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
                goto error;
        }
 
-       P9_DPRINTK(P9_DEBUG_9P, "clnt %p trans %p msize %d dotu %d\n",
+       P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d dotu %d\n",
                clnt, clnt->trans_mod, clnt->msize, clnt->dotu);
 
-
        err = clnt->trans_mod->create(clnt, dev_name, options);
        if (err)
                goto error;
@@ -636,38 +700,13 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
        if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
                clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
 
-       tc = p9_create_tversion(clnt->msize, clnt->dotu?"9P2000.u":"9P2000");
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
-               goto error;
-       }
-
-       err = p9_client_rpc(clnt, tc, &rc);
+       err = p9_client_version(clnt);
        if (err)
                goto error;
 
-       version = &rc->params.rversion.version;
-       if (version->len == 8 && !memcmp(version->str, "9P2000.u", 8))
-               clnt->dotu = 1;
-       else if (version->len == 6 && !memcmp(version->str, "9P2000", 6))
-               clnt->dotu = 0;
-       else {
-               err = -EREMOTEIO;
-               goto error;
-       }
-
-       n = rc->params.rversion.msize;
-       if (n < clnt->msize)
-               clnt->msize = n;
-
-       kfree(tc);
-       kfree(rc);
        return clnt;
 
 error:
-       kfree(tc);
-       kfree(rc);
        p9_client_destroy(clnt);
        return ERR_PTR(err);
 }
@@ -677,7 +716,7 @@ void p9_client_destroy(struct p9_client *clnt)
 {
        struct p9_fid *fid, *fidptr;
 
-       P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
+       P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
 
        if (clnt->trans_mod)
                clnt->trans_mod->close(clnt);
@@ -707,14 +746,13 @@ struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
        char *uname, u32 n_uname, char *aname)
 {
        int err;
-       struct p9_fcall *tc, *rc;
+       struct p9_req_t *req;
        struct p9_fid *fid;
+       struct p9_qid qid;
 
-       P9_DPRINTK(P9_DEBUG_9P, "clnt %p afid %d uname %s aname %s\n",
-               clnt, afid?afid->fid:-1, uname, aname);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
+                                       afid ? afid->fid : -1, uname, aname);
        err = 0;
-       tc = NULL;
-       rc = NULL;
 
        fid = p9_fid_create(clnt);
        if (IS_ERR(fid)) {
@@ -723,73 +761,81 @@ struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
                goto error;
        }
 
-       tc = p9_create_tattach(fid->fid, afid?afid->fid:P9_NOFID, uname, aname,
-               n_uname, clnt->dotu);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
+       req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
+                       afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
                goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
+       err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               p9_free_req(clnt, req);
                goto error;
+       }
 
-       memmove(&fid->qid, &rc->params.rattach.qid, sizeof(struct p9_qid));
-       kfree(tc);
-       kfree(rc);
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
+                                       qid.type,
+                                       (unsigned long long)qid.path,
+                                       qid.version);
+
+       memmove(&fid->qid, &qid, sizeof(struct p9_qid));
+
+       p9_free_req(clnt, req);
        return fid;
 
 error:
-       kfree(tc);
-       kfree(rc);
        if (fid)
                p9_fid_destroy(fid);
        return ERR_PTR(err);
 }
 EXPORT_SYMBOL(p9_client_attach);
 
-struct p9_fid *p9_client_auth(struct p9_client *clnt, char *uname,
-       u32 n_uname, char *aname)
+struct p9_fid *
+p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
 {
        int err;
-       struct p9_fcall *tc, *rc;
-       struct p9_fid *fid;
+       struct p9_req_t *req;
+       struct p9_qid qid;
+       struct p9_fid *afid;
 
-       P9_DPRINTK(P9_DEBUG_9P, "clnt %p uname %s aname %s\n", clnt, uname,
-                                                                       aname);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
        err = 0;
-       tc = NULL;
-       rc = NULL;
 
-       fid = p9_fid_create(clnt);
-       if (IS_ERR(fid)) {
-               err = PTR_ERR(fid);
-               fid = NULL;
+       afid = p9_fid_create(clnt);
+       if (IS_ERR(afid)) {
+               err = PTR_ERR(afid);
+               afid = NULL;
                goto error;
        }
 
-       tc = p9_create_tauth(fid->fid, uname, aname, n_uname, clnt->dotu);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
+       req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
+                       afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
                goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
+       err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               p9_free_req(clnt, req);
                goto error;
+       }
 
-       memmove(&fid->qid, &rc->params.rauth.qid, sizeof(struct p9_qid));
-       kfree(tc);
-       kfree(rc);
-       return fid;
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
+                                       qid.type,
+                                       (unsigned long long)qid.path,
+                                       qid.version);
+
+       memmove(&afid->qid, &qid, sizeof(struct p9_qid));
+       p9_free_req(clnt, req);
+       return afid;
 
 error:
-       kfree(tc);
-       kfree(rc);
-       if (fid)
-               p9_fid_destroy(fid);
+       if (afid)
+               p9_fid_destroy(afid);
        return ERR_PTR(err);
 }
 EXPORT_SYMBOL(p9_client_auth);
@@ -798,15 +844,13 @@ struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
        int clone)
 {
        int err;
-       struct p9_fcall *tc, *rc;
        struct p9_client *clnt;
        struct p9_fid *fid;
+       struct p9_qid *wqids;
+       struct p9_req_t *req;
+       int16_t nwqids, count;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d nwname %d wname[0] %s\n",
-               oldfid->fid, nwname, wnames?wnames[0]:NULL);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = oldfid->clnt;
        if (clone) {
                fid = p9_fid_create(clnt);
@@ -820,53 +864,50 @@ struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
        } else
                fid = oldfid;
 
-       tc = p9_create_twalk(oldfid->fid, fid->fid, nwname, wnames);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
+
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
+               oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
+
+       req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
+                                                               nwname, wnames);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
                goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
+       err = p9pdu_readf(req->rc, clnt->dotu, "R", &nwqids, &wqids);
        if (err) {
-               if (rc && rc->id == P9_RWALK)
-                       goto clunk_fid;
-               else
-                       goto error;
+               p9pdu_dump(1, req->rc);
+               p9_free_req(clnt, req);
+               goto clunk_fid;
        }
+       p9_free_req(clnt, req);
+
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
 
-       if (rc->params.rwalk.nwqid != nwname) {
+       if (nwqids != nwname) {
                err = -ENOENT;
                goto clunk_fid;
        }
 
+       for (count = 0; count < nwqids; count++)
+               P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
+                       count, wqids[count].type,
+                       (unsigned long long)wqids[count].path,
+                       wqids[count].version);
+
        if (nwname)
-               memmove(&fid->qid,
-                       &rc->params.rwalk.wqids[rc->params.rwalk.nwqid - 1],
-                       sizeof(struct p9_qid));
+               memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
        else
                fid->qid = oldfid->qid;
 
-       kfree(tc);
-       kfree(rc);
        return fid;
 
 clunk_fid:
-       kfree(tc);
-       kfree(rc);
-       rc = NULL;
-       tc = p9_create_tclunk(fid->fid);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
-               goto error;
-       }
-
-       p9_client_rpc(clnt, tc, &rc);
+       p9_client_clunk(fid);
+       fid = NULL;
 
 error:
-       kfree(tc);
-       kfree(rc);
        if (fid && (fid != oldfid))
                p9_fid_destroy(fid);
 
@@ -877,35 +918,41 @@ EXPORT_SYMBOL(p9_client_walk);
 int p9_client_open(struct p9_fid *fid, int mode)
 {
        int err;
-       struct p9_fcall *tc, *rc;
        struct p9_client *clnt;
+       struct p9_req_t *req;
+       struct p9_qid qid;
+       int iounit;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d mode %d\n", fid->fid, mode);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TOPEN fid %d mode %d\n", fid->fid, mode);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = fid->clnt;
 
        if (fid->mode != -1)
                return -EINVAL;
 
-       tc = p9_create_topen(fid->fid, mode);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
-               goto done;
+       req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
+               goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
-               goto done;
+       err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               goto free_and_error;
+       }
+
+       P9_DPRINTK(P9_DEBUG_9P, "<<< ROPEN qid %x.%llx.%x iounit %x\n",
+                               qid.type,
+                               (unsigned long long)qid.path,
+                               qid.version, iounit);
 
        fid->mode = mode;
-       fid->iounit = rc->params.ropen.iounit;
+       fid->iounit = iounit;
 
-done:
-       kfree(tc);
-       kfree(rc);
+free_and_error:
+       p9_free_req(clnt, req);
+error:
        return err;
 }
 EXPORT_SYMBOL(p9_client_open);
@@ -914,37 +961,43 @@ int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
                     char *extension)
 {
        int err;
-       struct p9_fcall *tc, *rc;
        struct p9_client *clnt;
+       struct p9_req_t *req;
+       struct p9_qid qid;
+       int iounit;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d name %s perm %d mode %d\n", fid->fid,
-               name, perm, mode);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
+                                               fid->fid, name, perm, mode);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = fid->clnt;
 
        if (fid->mode != -1)
                return -EINVAL;
 
-       tc = p9_create_tcreate(fid->fid, name, perm, mode, extension,
-                                                              clnt->dotu);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
-               goto done;
+       req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
+                               mode, extension);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
+               goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
-               goto done;
+       err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               goto free_and_error;
+       }
+
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
+                               qid.type,
+                               (unsigned long long)qid.path,
+                               qid.version, iounit);
 
        fid->mode = mode;
-       fid->iounit = rc->params.ropen.iounit;
+       fid->iounit = iounit;
 
-done:
-       kfree(tc);
-       kfree(rc);
+free_and_error:
+       p9_free_req(clnt, req);
+error:
        return err;
 }
 EXPORT_SYMBOL(p9_client_fcreate);
@@ -952,31 +1005,25 @@ EXPORT_SYMBOL(p9_client_fcreate);
 int p9_client_clunk(struct p9_fid *fid)
 {
        int err;
-       struct p9_fcall *tc, *rc;
        struct p9_client *clnt;
+       struct p9_req_t *req;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = fid->clnt;
 
-       tc = p9_create_tclunk(fid->fid);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
-               goto done;
+       req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
+               goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
-               goto done;
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
 
+       p9_free_req(clnt, req);
        p9_fid_destroy(fid);
 
-done:
-       kfree(tc);
-       kfree(rc);
+error:
        return err;
 }
 EXPORT_SYMBOL(p9_client_clunk);
@@ -984,31 +1031,25 @@ EXPORT_SYMBOL(p9_client_clunk);
 int p9_client_remove(struct p9_fid *fid)
 {
        int err;
-       struct p9_fcall *tc, *rc;
        struct p9_client *clnt;
+       struct p9_req_t *req;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = fid->clnt;
 
-       tc = p9_create_tremove(fid->fid);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
-               goto done;
+       req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
+               goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
-               goto done;
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
 
+       p9_free_req(clnt, req);
        p9_fid_destroy(fid);
 
-done:
-       kfree(tc);
-       kfree(rc);
+error:
        return err;
 }
 EXPORT_SYMBOL(p9_client_remove);
@@ -1017,15 +1058,14 @@ int
 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
                                                                u32 count)
 {
-       int err, n, rsize, total;
-       struct p9_fcall *tc, *rc;
+       int err, rsize, total;
        struct p9_client *clnt;
+       struct p9_req_t *req;
+       char *dataptr;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu %d\n", fid->fid,
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
                                        (long long unsigned) offset, count);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = fid->clnt;
        total = 0;
 
@@ -1033,53 +1073,41 @@ p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
        if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
                rsize = clnt->msize - P9_IOHDRSZ;
 
-       do {
-               if (count < rsize)
-                       rsize = count;
+       if (count < rsize)
+               rsize = count;
 
-               tc = p9_create_tread(fid->fid, offset, rsize);
-               if (IS_ERR(tc)) {
-                       err = PTR_ERR(tc);
-                       tc = NULL;
-                       goto error;
-               }
+       req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
+               goto error;
+       }
 
-               err = p9_client_rpc(clnt, tc, &rc);
-               if (err)
-                       goto error;
+       err = p9pdu_readf(req->rc, clnt->dotu, "D", &count, &dataptr);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               goto free_and_error;
+       }
 
-               n = rc->params.rread.count;
-               if (n > count)
-                       n = count;
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
 
-               if (data) {
-                       memmove(data, rc->params.rread.data, n);
-                       data += n;
-               }
+       if (data) {
+               memmove(data, dataptr, count);
+       }
 
-               if (udata) {
-                       err = copy_to_user(udata, rc->params.rread.data, n);
-                       if (err) {
-                               err = -EFAULT;
-                               goto error;
-                       }
-                       udata += n;
+       if (udata) {
+               err = copy_to_user(udata, dataptr, count);
+               if (err) {
+                       err = -EFAULT;
+                       goto free_and_error;
                }
+       }
 
-               count -= n;
-               offset += n;
-               total += n;
-               kfree(tc);
-               tc = NULL;
-               kfree(rc);
-               rc = NULL;
-       } while (count > 0 && n == rsize);
-
-       return total;
+       p9_free_req(clnt, req);
+       return count;
 
+free_and_error:
+       p9_free_req(clnt, req);
 error:
-       kfree(tc);
-       kfree(rc);
        return err;
 }
 EXPORT_SYMBOL(p9_client_read);
@@ -1088,15 +1116,13 @@ int
 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
                                                        u64 offset, u32 count)
 {
-       int err, n, rsize, total;
-       struct p9_fcall *tc, *rc;
+       int err, rsize, total;
        struct p9_client *clnt;
+       struct p9_req_t *req;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
-                                       (long long unsigned) offset, count);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
+                               fid->fid, (long long unsigned) offset, count);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = fid->clnt;
        total = 0;
 
@@ -1104,157 +1130,144 @@ p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
        if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
                rsize = clnt->msize - P9_IOHDRSZ;
 
-       do {
-               if (count < rsize)
-                       rsize = count;
-
-               if (data)
-                       tc = p9_create_twrite(fid->fid, offset, rsize, data);
-               else
-                       tc = p9_create_twrite_u(fid->fid, offset, rsize, udata);
-               if (IS_ERR(tc)) {
-                       err = PTR_ERR(tc);
-                       tc = NULL;
-                       goto error;
-               }
-
-               err = p9_client_rpc(clnt, tc, &rc);
-               if (err)
-                       goto error;
-
-               n = rc->params.rread.count;
-               count -= n;
+       if (count < rsize)
+               rsize = count;
+       if (data)
+               req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
+                                                               rsize, data);
+       else
+               req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
+                                                               rsize, udata);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
+               goto error;
+       }
 
-               if (data)
-                       data += n;
-               else
-                       udata += n;
+       err = p9pdu_readf(req->rc, clnt->dotu, "d", &count);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               goto free_and_error;
+       }
 
-               offset += n;
-               total += n;
-               kfree(tc);
-               tc = NULL;
-               kfree(rc);
-               rc = NULL;
-       } while (count > 0);
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
 
-       return total;
+       p9_free_req(clnt, req);
+       return count;
 
+free_and_error:
+       p9_free_req(clnt, req);
 error:
-       kfree(tc);
-       kfree(rc);
        return err;
 }
 EXPORT_SYMBOL(p9_client_write);
 
-static struct p9_stat *p9_clone_stat(struct p9_stat *st, int dotu)
+struct p9_wstat *p9_client_stat(struct p9_fid *fid)
 {
-       int n;
-       char *p;
-       struct p9_stat *ret;
-
-       n = sizeof(struct p9_stat) + st->name.len + st->uid.len + st->gid.len +
-               st->muid.len;
+       int err;
+       struct p9_client *clnt;
+       struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
+       struct p9_req_t *req;
+       u16 ignored;
 
-       if (dotu)
-               n += st->extension.len;
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
 
-       ret = kmalloc(n, GFP_KERNEL);
        if (!ret)
                return ERR_PTR(-ENOMEM);
 
-       memmove(ret, st, sizeof(struct p9_stat));
-       p = ((char *) ret) + sizeof(struct p9_stat);
-       memmove(p, st->name.str, st->name.len);
-       ret->name.str = p;
-       p += st->name.len;
-       memmove(p, st->uid.str, st->uid.len);
-       ret->uid.str = p;
-       p += st->uid.len;
-       memmove(p, st->gid.str, st->gid.len);
-       ret->gid.str = p;
-       p += st->gid.len;
-       memmove(p, st->muid.str, st->muid.len);
-       ret->muid.str = p;
-       p += st->muid.len;
-
-       if (dotu) {
-               memmove(p, st->extension.str, st->extension.len);
-               ret->extension.str = p;
-               p += st->extension.len;
-       }
-
-       return ret;
-}
-
-struct p9_stat *p9_client_stat(struct p9_fid *fid)
-{
-       int err;
-       struct p9_fcall *tc, *rc;
-       struct p9_client *clnt;
-       struct p9_stat *ret;
-
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
        err = 0;
-       tc = NULL;
-       rc = NULL;
-       ret = NULL;
        clnt = fid->clnt;
 
-       tc = p9_create_tstat(fid->fid);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
+       req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
                goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
-               goto error;
-
-       ret = p9_clone_stat(&rc->params.rstat.stat, clnt->dotu);
-       if (IS_ERR(ret)) {
-               err = PTR_ERR(ret);
-               ret = NULL;
+       err = p9pdu_readf(req->rc, clnt->dotu, "wS", &ignored, ret);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               p9_free_req(clnt, req);
                goto error;
        }
 
-       kfree(tc);
-       kfree(rc);
+       P9_DPRINTK(P9_DEBUG_9P,
+               "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
+               "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
+               "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
+               "<<<    uid=%d gid=%d n_muid=%d\n",
+               ret->size, ret->type, ret->dev, ret->qid.type,
+               (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
+               ret->atime, ret->mtime, (unsigned long long)ret->length,
+               ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
+               ret->n_uid, ret->n_gid, ret->n_muid);
+
+       p9_free_req(clnt, req);
        return ret;
 
 error:
-       kfree(tc);
-       kfree(rc);
        kfree(ret);
        return ERR_PTR(err);
 }
 EXPORT_SYMBOL(p9_client_stat);
 
+static int p9_client_statsize(struct p9_wstat *wst, int optional)
+{
+       int ret;
+
+       /* size[2] type[2] dev[4] qid[13] */
+       /* mode[4] atime[4] mtime[4] length[8]*/
+       /* name[s] uid[s] gid[s] muid[s] */
+       ret = 2+2+4+13+4+4+4+8+2+2+2+2;
+
+       if (wst->name)
+               ret += strlen(wst->name);
+       if (wst->uid)
+               ret += strlen(wst->uid);
+       if (wst->gid)
+               ret += strlen(wst->gid);
+       if (wst->muid)
+               ret += strlen(wst->muid);
+
+       if (optional) {
+               ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
+               if (wst->extension)
+                       ret += strlen(wst->extension);
+       }
+
+       return ret;
+}
+
 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
 {
        int err;
-       struct p9_fcall *tc, *rc;
+       struct p9_req_t *req;
        struct p9_client *clnt;
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
        err = 0;
-       tc = NULL;
-       rc = NULL;
        clnt = fid->clnt;
-
-       tc = p9_create_twstat(fid->fid, wst, clnt->dotu);
-       if (IS_ERR(tc)) {
-               err = PTR_ERR(tc);
-               tc = NULL;
-               goto done;
+       wst->size = p9_client_statsize(wst, clnt->dotu);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
+       P9_DPRINTK(P9_DEBUG_9P,
+               "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
+               "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
+               "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
+               "     uid=%d gid=%d n_muid=%d\n",
+               wst->size, wst->type, wst->dev, wst->qid.type,
+               (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
+               wst->atime, wst->mtime, (unsigned long long)wst->length,
+               wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
+               wst->n_uid, wst->n_gid, wst->n_muid);
+
+       req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size, wst);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
+               goto error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
 
-done:
-       kfree(tc);
-       kfree(rc);
+       p9_free_req(clnt, req);
+error:
        return err;
 }
 EXPORT_SYMBOL(p9_client_wstat);