]> nv-tegra.nvidia Code Review - linux-2.6.git/blobdiff - net/9p/client.c
net/9p: insulate the client against an invalid error code sent by a 9p server
[linux-2.6.git] / net / 9p / client.c
index f1a52a7ed7248d5fc919cd6420f195334386a6a3..5bf5f227dbe0d83eaf28cc400a665594c6452a22 100644 (file)
 #include <linux/parser.h>
 #include <net/9p/client.h>
 #include <net/9p/transport.h>
-
-static struct p9_fid *p9_fid_create(struct p9_client *clnt);
-static void p9_fid_destroy(struct p9_fid *fid);
-static struct p9_stat *p9_clone_stat(struct p9_stat *st, int dotu);
+#include "protocol.h"
 
 /*
   * Client Option Parsing (code inspired by NFS code)
@@ -59,10 +56,13 @@ static const match_table_t tokens = {
        {Opt_err, NULL},
 };
 
+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
  */
@@ -117,38 +117,549 @@ 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;
 }
 
+/**
+ * p9_tag_alloc - lookup/allocate a request by tag
+ * @c: client session to lookup tag within
+ * @tag: numeric id for transaction
+ *
+ * this is a simple array lookup, but will grow the
+ * request_slots as necessary to accomodate transaction
+ * ids which did not previously have a slot.
+ *
+ * this code relies on the client spinlock to manage locks, its
+ * possible we should switch to something else, but I'd rather
+ * stick with something low-overhead for the common case.
+ *
+ */
+
+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 */
+       tag++;
+
+       if (tag >= c->max_tag) {
+               spin_lock_irqsave(&c->lock, flags);
+               /* check again since original check was outside of lock */
+               while (tag >= c->max_tag) {
+                       row = (tag / P9_ROW_MAXTAG);
+                       c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
+                                       sizeof(struct p9_req_t), GFP_ATOMIC);
+
+                       if (!c->reqs[row]) {
+                               printk(KERN_ERR "Couldn't grow tag array\n");
+                               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].tc = NULL;
+                       }
+                       c->max_tag += P9_ROW_MAXTAG;
+               }
+               spin_unlock_irqrestore(&c->lock, flags);
+       }
+       row = tag / P9_ROW_MAXTAG;
+       col = tag % P9_ROW_MAXTAG;
+
+       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];
+}
+
+/**
+ * p9_tag_lookup - lookup a request by tag
+ * @c: client session to lookup tag within
+ * @tag: numeric id for transaction
+ *
+ */
+
+struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
+{
+       int row, col;
+
+       /* This looks up the original request by tag so we know which
+        * buffer to read the data into */
+       tag++;
+
+       BUG_ON(tag >= c->max_tag);
+
+       row = tag / P9_ROW_MAXTAG;
+       col = tag % P9_ROW_MAXTAG;
+
+       return &c->reqs[row][col];
+}
+EXPORT_SYMBOL(p9_tag_lookup);
+
+/**
+ * p9_tag_init - setup tags structure and contents
+ * @c:  v9fs client struct
+ *
+ * This initializes the tags structure for each client instance.
+ *
+ */
+
+static int p9_tag_init(struct p9_client *c)
+{
+       int err = 0;
+
+       c->tagpool = p9_idpool_create();
+       if (IS_ERR(c->tagpool)) {
+               err = PTR_ERR(c->tagpool);
+               c->tagpool = NULL;
+               goto error;
+       }
+
+       p9_idpool_get(c->tagpool); /* reserve tag 0 */
+
+       c->max_tag = 0;
+error:
+       return err;
+}
+
+/**
+ * p9_tag_cleanup - cleans up tags structure and reclaims resources
+ * @c:  v9fs client struct
+ *
+ * This frees resources associated with the tags structure
+ *
+ */
+static void p9_tag_cleanup(struct p9_client *c)
+{
+       int row, col;
+
+       /* check to insure all requests are idle */
+       for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
+               for (col = 0; col < P9_ROW_MAXTAG; col++) {
+                       if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
+                               P9_DPRINTK(P9_DEBUG_MUX,
+                                 "Attempting to cleanup non-free tag %d,%d\n",
+                                 row, col);
+                               /* TODO: delay execution of cleanup */
+                               return;
+                       }
+               }
+       }
+
+       if (c->tagpool)
+               p9_idpool_destroy(c->tagpool);
+
+       /* free requests associated with tags */
+       for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
+               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_free_req - free a request and clean-up as necessary
+ * c: client state
+ * r: request to release
+ *
+ */
+
+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);
 
 /**
- * p9_client_rpc - sends 9P request and waits until a response is available.
- *      The function can be interrupted.
- * @c: client data
- * @tc: request to be sent
- * @rc: pointer where a pointer to the response is stored
+ * 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_client_rpc(struct p9_client *c, struct p9_fcall *tc,
-       struct p9_fcall **rc)
+p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
+                                                               int rewind)
+{
+       int8_t r_type;
+       int16_t r_tag;
+       int32_t r_size;
+       int offset = pdu->offset;
+       int err;
+
+       pdu->offset = 0;
+       if (pdu->size == 0)
+               pdu->size = 7;
+
+       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;
+
+       P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
+                                                       pdu->id, pdu->tag);
+
+       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_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
+ */
+
+static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
+{
+       int8_t type;
+       int err;
+
+       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_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.
+ *
+ */
+
+static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
+{
+       struct p9_req_t *req;
+       int16_t oldtag;
+       int err;
+
+       err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
+       if (err)
+               return err;
+
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
+
+       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;
+}
+
+/**
+ * p9_client_rpc - issue a request and wait for a response
+ * @c: client session
+ * @type: type of request
+ * @fmt: protocol format string (see protocol.c)
+ *
+ * Returns request structure (which client must free using p9_free_req)
+ */
+
+static struct p9_req_t *
+p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
+{
+       va_list ap;
+       int tag, err;
+       struct p9_req_t *req;
+       unsigned long flags;
+       int sigpending;
+
+       P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
+
+       if (c->status != Connected)
+               return ERR_PTR(-EIO);
+
+       if (signal_pending(current)) {
+               sigpending = 1;
+               clear_thread_flag(TIF_SIGPENDING);
+       } else
+               sigpending = 0;
+
+       tag = P9_NOTAG;
+       if (type != P9_TVERSION) {
+               tag = p9_idpool_get(c->tagpool);
+               if (tag < 0)
+                       return ERR_PTR(-ENOMEM);
+       }
+
+       req = p9_tag_alloc(c, tag);
+       if (IS_ERR(req))
+               return req;
+
+       /* 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) {
+               c->status = Disconnected;
+               goto reterr;
+       }
+
+       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_MUX, "wait %p tag: %d returned %d\n",
+                                               req->wq, tag, err);
+
+       if (req->status == REQ_STATUS_ERROR) {
+               P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
+               err = req->t_err;
+       }
+
+       if ((err == -ERESTARTSYS) && (c->status == Connected)) {
+               P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
+               sigpending = 1;
+               clear_thread_flag(TIF_SIGPENDING);
+
+               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) {
+               spin_lock_irqsave(&current->sighand->siglock, flags);
+               recalc_sigpending();
+               spin_unlock_irqrestore(&current->sighand->siglock, flags);
+       }
+
+       if (err < 0)
+               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;
+       }
+
+reterr:
+       P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
+                                                                       err);
+       p9_free_req(c, req);
+       return ERR_PTR(err);
+}
+
+static struct p9_fid *p9_fid_create(struct p9_client *clnt)
+{
+       int ret;
+       struct p9_fid *fid;
+       unsigned long flags;
+
+       P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
+       fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
+       if (!fid)
+               return ERR_PTR(-ENOMEM);
+
+       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->clnt = clnt;
+       fid->aux = NULL;
+
+       spin_lock_irqsave(&clnt->lock, flags);
+       list_add(&fid->flist, &clnt->fidlist);
+       spin_unlock_irqrestore(&clnt->lock, flags);
+
+       return fid;
+
+error:
+       kfree(fid);
+       return ERR_PTR(ret);
+}
+
+static void p9_fid_destroy(struct p9_fid *fid)
+{
+       struct p9_client *clnt;
+       unsigned long flags;
+
+       P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
+       clnt = fid->clnt;
+       p9_idpool_put(fid->fid, clnt->fidpool);
+       spin_lock_irqsave(&clnt->lock, flags);
+       list_del(&fid->flist);
+       spin_unlock_irqrestore(&clnt->lock, flags);
+       kfree(fid);
+}
+
+int p9_client_version(struct p9_client *c)
 {
-       return c->trans_mod->rpc(c, tc, rc);
+       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);
@@ -164,10 +675,15 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
                goto error;
        }
 
+       p9_tag_init(clnt);
+
        err = parse_opts(options, clnt);
        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,
@@ -175,10 +691,9 @@ 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;
@@ -186,38 +701,13 @@ 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);
 }
@@ -227,7 +717,7 @@ 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);
@@ -240,6 +730,8 @@ void p9_client_destroy(struct p9_client *clnt)
        if (clnt->fidpool)
                p9_idpool_destroy(clnt->fidpool);
 
+       p9_tag_cleanup(clnt);
+
        kfree(clnt);
 }
 EXPORT_SYMBOL(p9_client_destroy);
@@ -255,14 +747,13 @@ 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)) {
@@ -271,73 +762,81 @@ 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);
@@ -346,15 +845,13 @@ 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);
@@ -368,53 +865,50 @@ 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);
 
@@ -425,35 +919,41 @@ 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 = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               goto free_and_error;
        }
 
-       err = p9_client_rpc(clnt, tc, &rc);
-       if (err)
-               goto done;
+       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);
@@ -462,37 +962,43 @@ 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);
@@ -500,31 +1006,25 @@ 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);
@@ -532,157 +1032,41 @@ 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);
-       return err;
-}
-EXPORT_SYMBOL(p9_client_remove);
-
-int p9_client_read(struct p9_fid *fid, char *data, u64 offset, u32 count)
-{
-       int err, n, rsize, total;
-       struct p9_fcall *tc, *rc;
-       struct p9_client *clnt;
-
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu %d\n", fid->fid,
-                                       (long long unsigned) offset, count);
-       err = 0;
-       tc = NULL;
-       rc = NULL;
-       clnt = fid->clnt;
-       total = 0;
-
-       rsize = fid->iounit;
-       if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
-               rsize = clnt->msize - P9_IOHDRSZ;
-
-       do {
-               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;
-               }
-
-               err = p9_client_rpc(clnt, tc, &rc);
-               if (err)
-                       goto error;
-
-               n = rc->params.rread.count;
-               if (n > count)
-                       n = count;
-
-               memmove(data, rc->params.rread.data, n);
-               count -= n;
-               data += n;
-               offset += n;
-               total += n;
-               kfree(tc);
-               tc = NULL;
-               kfree(rc);
-               rc = NULL;
-       } while (count > 0 && n == rsize);
-
-       return total;
-
-error:
-       kfree(tc);
-       kfree(rc);
-       return err;
-}
-EXPORT_SYMBOL(p9_client_read);
-
-int p9_client_write(struct p9_fid *fid, char *data, u64 offset, u32 count)
-{
-       int err, n, rsize, total;
-       struct p9_fcall *tc, *rc;
-       struct p9_client *clnt;
-
-       P9_DPRINTK(P9_DEBUG_9P, "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;
-
-       rsize = fid->iounit;
-       if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
-               rsize = clnt->msize - P9_IOHDRSZ;
-
-       do {
-               if (count < rsize)
-                       rsize = count;
-
-               tc = p9_create_twrite(fid->fid, offset, rsize, data);
-               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;
-               data += n;
-               offset += n;
-               total += n;
-               kfree(tc);
-               tc = NULL;
-               kfree(rc);
-               rc = NULL;
-       } while (count > 0);
-
-       return total;
-
 error:
-       kfree(tc);
-       kfree(rc);
        return err;
 }
-EXPORT_SYMBOL(p9_client_write);
+EXPORT_SYMBOL(p9_client_remove);
 
 int
-p9_client_uread(struct p9_fid *fid, char __user *data, u64 offset, u32 count)
+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 count %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;
 
@@ -690,63 +1074,56 @@ p9_client_uread(struct p9_fid *fid, char __user *data, u64 offset, u32 count)
        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;
+       }
+
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
 
-               n = rc->params.rread.count;
-               if (n > count)
-                       n = count;
+       if (data) {
+               memmove(data, dataptr, count);
+       }
 
-               err = copy_to_user(data, rc->params.rread.data, n);
+       if (udata) {
+               err = copy_to_user(udata, dataptr, count);
                if (err) {
                        err = -EFAULT;
-                       goto error;
+                       goto free_and_error;
                }
+       }
 
-               count -= n;
-               data += 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_uread);
+EXPORT_SYMBOL(p9_client_read);
 
 int
-p9_client_uwrite(struct p9_fid *fid, const char __user *data, u64 offset,
-                                                                  u32 count)
+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;
 
@@ -754,325 +1131,144 @@ p9_client_uwrite(struct p9_fid *fid, const char __user *data, u64 offset,
        if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
                rsize = clnt->msize - P9_IOHDRSZ;
 
-       do {
-               if (count < rsize)
-                       rsize = count;
-
-               tc = p9_create_twrite_u(fid->fid, offset, rsize, data);
-               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;
-               data += n;
-               offset += n;
-               total += n;
-               kfree(tc);
-               tc = NULL;
-               kfree(rc);
-               rc = NULL;
-       } while (count > 0);
-
-       return total;
-
-error:
-       kfree(tc);
-       kfree(rc);
-       return err;
-}
-EXPORT_SYMBOL(p9_client_uwrite);
-
-int p9_client_readn(struct p9_fid *fid, char *data, u64 offset, u32 count)
-{
-       int n, total;
-
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
-                                       (long long unsigned) offset, count);
-       n = 0;
-       total = 0;
-       while (count) {
-               n = p9_client_read(fid, data, offset, count);
-               if (n <= 0)
-                       break;
-
-               data += n;
-               offset += n;
-               count -= n;
-               total += n;
-       }
-
-       if (n < 0)
-               total = n;
-
-       return total;
-}
-EXPORT_SYMBOL(p9_client_readn);
-
-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;
+       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;
        }
 
-       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;
-               goto error;
+       err = p9pdu_readf(req->rc, clnt->dotu, "d", &count);
+       if (err) {
+               p9pdu_dump(1, req->rc);
+               goto free_and_error;
        }
 
-       kfree(tc);
-       kfree(rc);
-       return ret;
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
 
+       p9_free_req(clnt, req);
+       return count;
+
+free_and_error:
+       p9_free_req(clnt, req);
 error:
-       kfree(tc);
-       kfree(rc);
-       kfree(ret);
-       return ERR_PTR(err);
+       return err;
 }
-EXPORT_SYMBOL(p9_client_stat);
+EXPORT_SYMBOL(p9_client_write);
 
-int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
+struct p9_wstat *p9_client_stat(struct p9_fid *fid)
 {
        int err;
-       struct p9_fcall *tc, *rc;
        struct p9_client *clnt;
+       struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
+       struct p9_req_t *req;
+       u16 ignored;
 
-       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;
-       }
-
-       err = p9_client_rpc(clnt, tc, &rc);
-
-done:
-       kfree(tc);
-       kfree(rc);
-       return err;
-}
-EXPORT_SYMBOL(p9_client_wstat);
+       P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
 
-struct p9_stat *p9_client_dirread(struct p9_fid *fid, u64 offset)
-{
-       int err, n, m;
-       struct p9_fcall *tc, *rc;
-       struct p9_client *clnt;
-       struct p9_stat st, *ret;
+       if (!ret)
+               return ERR_PTR(-ENOMEM);
 
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu\n", fid->fid,
-                                               (long long unsigned) offset);
        err = 0;
-       tc = NULL;
-       rc = NULL;
-       ret = NULL;
        clnt = fid->clnt;
 
-       /* if the offset is below or above the current response, free it */
-       if (offset < fid->rdir_fpos || (fid->rdir_fcall &&
-               offset >= fid->rdir_fpos+fid->rdir_fcall->params.rread.count)) {
-               fid->rdir_pos = 0;
-               if (fid->rdir_fcall)
-                       fid->rdir_fpos += fid->rdir_fcall->params.rread.count;
-
-               kfree(fid->rdir_fcall);
-               fid->rdir_fcall = NULL;
-               if (offset < fid->rdir_fpos)
-                       fid->rdir_fpos = 0;
-       }
-
-       if (!fid->rdir_fcall) {
-               n = fid->iounit;
-               if (!n || n > clnt->msize-P9_IOHDRSZ)
-                       n = clnt->msize - P9_IOHDRSZ;
-
-               while (1) {
-                       if (fid->rdir_fcall) {
-                               fid->rdir_fpos +=
-                                       fid->rdir_fcall->params.rread.count;
-                               kfree(fid->rdir_fcall);
-                               fid->rdir_fcall = NULL;
-                       }
-
-                       tc = p9_create_tread(fid->fid, fid->rdir_fpos, n);
-                       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;
-                       if (n == 0)
-                               goto done;
-
-                       fid->rdir_fcall = rc;
-                       rc = NULL;
-                       if (offset >= fid->rdir_fpos &&
-                                               offset < fid->rdir_fpos+n)
-                               break;
-               }
-
-               fid->rdir_pos = 0;
-       }
-
-       m = offset - fid->rdir_fpos;
-       if (m < 0)
-               goto done;
-
-       n = p9_deserialize_stat(fid->rdir_fcall->params.rread.data + m,
-               fid->rdir_fcall->params.rread.count - m, &st, clnt->dotu);
-
-       if (!n) {
-               err = -EIO;
+       req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
+       if (IS_ERR(req)) {
+               err = PTR_ERR(req);
                goto error;
        }
 
-       fid->rdir_pos += n;
-       st.size = n;
-       ret = p9_clone_stat(&st, 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;
        }
 
-done:
-       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_dirread);
+EXPORT_SYMBOL(p9_client_stat);
 
-static struct p9_stat *p9_clone_stat(struct p9_stat *st, int dotu)
+static int p9_client_statsize(struct p9_wstat *wst, int optional)
 {
-       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;
-
-       if (dotu)
-               n += st->extension.len;
-
-       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;
+       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;
 }
 
-static struct p9_fid *p9_fid_create(struct p9_client *clnt)
+int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
 {
        int err;
-       struct p9_fid *fid;
-
-       P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
-       fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
-       if (!fid)
-               return ERR_PTR(-ENOMEM);
+       struct p9_req_t *req;
+       struct p9_client *clnt;
 
-       fid->fid = p9_idpool_get(clnt->fidpool);
-       if (fid->fid < 0) {
-               err = -ENOSPC;
+       err = 0;
+       clnt = fid->clnt;
+       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;
        }
 
-       memset(&fid->qid, 0, sizeof(struct p9_qid));
-       fid->mode = -1;
-       fid->rdir_fpos = 0;
-       fid->rdir_pos = 0;
-       fid->rdir_fcall = NULL;
-       fid->uid = current->fsuid;
-       fid->clnt = clnt;
-       fid->aux = NULL;
-
-       spin_lock(&clnt->lock);
-       list_add(&fid->flist, &clnt->fidlist);
-       spin_unlock(&clnt->lock);
-
-       return fid;
+       P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
 
+       p9_free_req(clnt, req);
 error:
-       kfree(fid);
-       return ERR_PTR(err);
-}
-
-static void p9_fid_destroy(struct p9_fid *fid)
-{
-       struct p9_client *clnt;
-
-       P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
-       clnt = fid->clnt;
-       p9_idpool_put(fid->fid, clnt->fidpool);
-       spin_lock(&clnt->lock);
-       list_del(&fid->flist);
-       spin_unlock(&clnt->lock);
-       kfree(fid->rdir_fcall);
-       kfree(fid);
+       return err;
 }
+EXPORT_SYMBOL(p9_client_wstat);