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-rw-r--r--fs/9p/mux.c475
1 files changed, 0 insertions, 475 deletions
diff --git a/fs/9p/mux.c b/fs/9p/mux.c
deleted file mode 100644
index 8835b576f74..00000000000
--- a/fs/9p/mux.c
+++ /dev/null
@@ -1,475 +0,0 @@
-/*
- * linux/fs/9p/mux.c
- *
- * Protocol Multiplexer
- *
- * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
- * Copyright (C) 2004 by Latchesar Ionkov <lucho@ionkov.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to:
- * Free Software Foundation
- * 51 Franklin Street, Fifth Floor
- * Boston, MA 02111-1301 USA
- *
- */
-
-#include <linux/config.h>
-#include <linux/module.h>
-#include <linux/errno.h>
-#include <linux/fs.h>
-#include <linux/kthread.h>
-#include <linux/idr.h>
-
-#include "debug.h"
-#include "v9fs.h"
-#include "9p.h"
-#include "transport.h"
-#include "conv.h"
-#include "mux.h"
-
-/**
- * dprintcond - print condition of session info
- * @v9ses: session info structure
- * @req: RPC request structure
- *
- */
-
-static inline int
-dprintcond(struct v9fs_session_info *v9ses, struct v9fs_rpcreq *req)
-{
- dprintk(DEBUG_MUX, "condition: %d, %p\n", v9ses->transport->status,
- req->rcall);
- return 0;
-}
-
-/**
- * xread - force read of a certain number of bytes
- * @v9ses: session info structure
- * @ptr: pointer to buffer
- * @sz: number of bytes to read
- *
- * Chuck Cranor CS-533 project1
- */
-
-static int xread(struct v9fs_session_info *v9ses, void *ptr, unsigned long sz)
-{
- int rd = 0;
- int ret = 0;
- while (rd < sz) {
- ret = v9ses->transport->read(v9ses->transport, ptr, sz - rd);
- if (ret <= 0) {
- dprintk(DEBUG_ERROR, "xread errno %d\n", ret);
- return ret;
- }
- rd += ret;
- ptr += ret;
- }
- return (rd);
-}
-
-/**
- * read_message - read a full 9P2000 fcall packet
- * @v9ses: session info structure
- * @rcall: fcall structure to read into
- * @rcalllen: size of fcall buffer
- *
- */
-
-static int
-read_message(struct v9fs_session_info *v9ses,
- struct v9fs_fcall *rcall, int rcalllen)
-{
- unsigned char buf[4];
- void *data;
- int size = 0;
- int res = 0;
-
- res = xread(v9ses, buf, sizeof(buf));
- if (res < 0) {
- dprintk(DEBUG_ERROR,
- "Reading of count field failed returned: %d\n", res);
- return res;
- }
-
- if (res < 4) {
- dprintk(DEBUG_ERROR,
- "Reading of count field failed returned: %d\n", res);
- return -EIO;
- }
-
- size = buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
- dprintk(DEBUG_MUX, "got a packet count: %d\n", size);
-
- /* adjust for the four bytes of size */
- size -= 4;
-
- if (size > v9ses->maxdata) {
- dprintk(DEBUG_ERROR, "packet too big: %d\n", size);
- return -E2BIG;
- }
-
- data = kmalloc(size, GFP_KERNEL);
- if (!data) {
- eprintk(KERN_WARNING, "out of memory\n");
- return -ENOMEM;
- }
-
- res = xread(v9ses, data, size);
- if (res < size) {
- dprintk(DEBUG_ERROR, "Reading of fcall failed returned: %d\n",
- res);
- kfree(data);
- return res;
- }
-
- /* we now have an in-memory string that is the reply.
- * deserialize it. There is very little to go wrong at this point
- * save for v9fs_alloc errors.
- */
- res = v9fs_deserialize_fcall(v9ses, size, data, v9ses->maxdata,
- rcall, rcalllen);
-
- kfree(data);
-
- if (res < 0)
- return res;
-
- return 0;
-}
-
-/**
- * v9fs_recv - receive an RPC response for a particular tag
- * @v9ses: session info structure
- * @req: RPC request structure
- *
- */
-
-static int v9fs_recv(struct v9fs_session_info *v9ses, struct v9fs_rpcreq *req)
-{
- int ret = 0;
-
- dprintk(DEBUG_MUX, "waiting for response: %d\n", req->tcall->tag);
- ret = wait_event_interruptible(v9ses->read_wait,
- ((v9ses->transport->status != Connected) ||
- (req->rcall != 0) || (req->err < 0) ||
- dprintcond(v9ses, req)));
-
- dprintk(DEBUG_MUX, "got it: rcall %p\n", req->rcall);
-
- spin_lock(&v9ses->muxlock);
- list_del(&req->next);
- spin_unlock(&v9ses->muxlock);
-
- if (req->err < 0)
- return req->err;
-
- if (v9ses->transport->status == Disconnected)
- return -ECONNRESET;
-
- return ret;
-}
-
-/**
- * v9fs_send - send a 9P request
- * @v9ses: session info structure
- * @req: RPC request to send
- *
- */
-
-static int v9fs_send(struct v9fs_session_info *v9ses, struct v9fs_rpcreq *req)
-{
- int ret = -1;
- void *data = NULL;
- struct v9fs_fcall *tcall = req->tcall;
-
- data = kmalloc(v9ses->maxdata + V9FS_IOHDRSZ, GFP_KERNEL);
- if (!data)
- return -ENOMEM;
-
- tcall->size = 0; /* enforce size recalculation */
- ret =
- v9fs_serialize_fcall(v9ses, tcall, data,
- v9ses->maxdata + V9FS_IOHDRSZ);
- if (ret < 0)
- goto free_data;
-
- spin_lock(&v9ses->muxlock);
- list_add(&req->next, &v9ses->mux_fcalls);
- spin_unlock(&v9ses->muxlock);
-
- dprintk(DEBUG_MUX, "sending message: tag %d size %d\n", tcall->tag,
- tcall->size);
- ret = v9ses->transport->write(v9ses->transport, data, tcall->size);
-
- if (ret != tcall->size) {
- spin_lock(&v9ses->muxlock);
- list_del(&req->next);
- kfree(req->rcall);
-
- spin_unlock(&v9ses->muxlock);
- if (ret >= 0)
- ret = -EREMOTEIO;
- } else
- ret = 0;
-
- free_data:
- kfree(data);
- return ret;
-}
-
-/**
- * v9fs_mux_rpc - send a request, receive a response
- * @v9ses: session info structure
- * @tcall: fcall to send
- * @rcall: buffer to place response into
- *
- */
-
-long
-v9fs_mux_rpc(struct v9fs_session_info *v9ses, struct v9fs_fcall *tcall,
- struct v9fs_fcall **rcall)
-{
- int tid = -1;
- struct v9fs_fcall *fcall = NULL;
- struct v9fs_rpcreq req;
- int ret = -1;
-
- if (!v9ses)
- return -EINVAL;
-
- if (!v9ses->transport || v9ses->transport->status != Connected)
- return -EIO;
-
- if (rcall)
- *rcall = NULL;
-
- if (tcall->id != TVERSION) {
- tid = v9fs_get_idpool(&v9ses->tidpool);
- if (tid < 0)
- return -ENOMEM;
- }
-
- tcall->tag = tid;
-
- req.tcall = tcall;
- req.err = 0;
- req.rcall = NULL;
-
- ret = v9fs_send(v9ses, &req);
-
- if (ret < 0) {
- if (tcall->id != TVERSION)
- v9fs_put_idpool(tid, &v9ses->tidpool);
- dprintk(DEBUG_MUX, "error %d\n", ret);
- return ret;
- }
-
- ret = v9fs_recv(v9ses, &req);
-
- fcall = req.rcall;
-
- dprintk(DEBUG_MUX, "received: tag=%x, ret=%d\n", tcall->tag, ret);
- if (ret == -ERESTARTSYS) {
- if (v9ses->transport->status != Disconnected
- && tcall->id != TFLUSH) {
- unsigned long flags;
-
- dprintk(DEBUG_MUX, "flushing the tag: %d\n",
- tcall->tag);
- clear_thread_flag(TIF_SIGPENDING);
- v9fs_t_flush(v9ses, tcall->tag);
- spin_lock_irqsave(&current->sighand->siglock, flags);
- recalc_sigpending();
- spin_unlock_irqrestore(&current->sighand->siglock,
- flags);
- dprintk(DEBUG_MUX, "flushing done\n");
- }
-
- goto release_req;
- } else if (ret < 0)
- goto release_req;
-
- if (!fcall)
- ret = -EIO;
- else {
- if (fcall->id == RERROR) {
- ret = v9fs_errstr2errno(fcall->params.rerror.error);
- if (ret == 0) { /* string match failed */
- if (fcall->params.rerror.errno)
- ret = -(fcall->params.rerror.errno);
- else
- ret = -ESERVERFAULT;
- }
- } else if (fcall->id != tcall->id + 1) {
- dprintk(DEBUG_ERROR,
- "fcall mismatch: expected %d, got %d\n",
- tcall->id + 1, fcall->id);
- ret = -EIO;
- }
- }
-
- release_req:
- if (tcall->id != TVERSION)
- v9fs_put_idpool(tid, &v9ses->tidpool);
- if (rcall)
- *rcall = fcall;
- else
- kfree(fcall);
-
- return ret;
-}
-
-/**
- * v9fs_mux_cancel_requests - cancels all pending requests
- *
- * @v9ses: session info structure
- * @err: error code to return to the requests
- */
-void v9fs_mux_cancel_requests(struct v9fs_session_info *v9ses, int err)
-{
- struct v9fs_rpcreq *rptr;
- struct v9fs_rpcreq *rreq;
-
- dprintk(DEBUG_MUX, " %d\n", err);
- spin_lock(&v9ses->muxlock);
- list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
- rreq->err = err;
- }
- spin_unlock(&v9ses->muxlock);
- wake_up_all(&v9ses->read_wait);
-}
-
-/**
- * v9fs_recvproc - kproc to handle demultiplexing responses
- * @data: session info structure
- *
- */
-
-static int v9fs_recvproc(void *data)
-{
- struct v9fs_session_info *v9ses = (struct v9fs_session_info *)data;
- struct v9fs_fcall *rcall = NULL;
- struct v9fs_rpcreq *rptr;
- struct v9fs_rpcreq *req;
- struct v9fs_rpcreq *rreq;
- int err = 0;
-
- allow_signal(SIGKILL);
- set_current_state(TASK_INTERRUPTIBLE);
- complete(&v9ses->proccmpl);
- while (!kthread_should_stop() && err >= 0) {
- req = rptr = rreq = NULL;
-
- rcall = kmalloc(v9ses->maxdata + V9FS_IOHDRSZ, GFP_KERNEL);
- if (!rcall) {
- eprintk(KERN_ERR, "no memory for buffers\n");
- break;
- }
-
- err = read_message(v9ses, rcall, v9ses->maxdata + V9FS_IOHDRSZ);
- spin_lock(&v9ses->muxlock);
- if (err < 0) {
- list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
- rreq->err = err;
- }
- if(err != -ERESTARTSYS)
- eprintk(KERN_ERR,
- "Transport error while reading message %d\n", err);
- } else {
- list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
- if (rreq->tcall->tag == rcall->tag) {
- req = rreq;
- req->rcall = rcall;
- break;
- }
- }
- }
-
- if (req && (req->tcall->id == TFLUSH)) {
- struct v9fs_rpcreq *treq = NULL;
- list_for_each_entry_safe(treq, rptr, &v9ses->mux_fcalls, next) {
- if (treq->tcall->tag ==
- req->tcall->params.tflush.oldtag) {
- list_del(&rptr->next);
- kfree(treq->rcall);
- break;
- }
- }
- }
-
- spin_unlock(&v9ses->muxlock);
-
- if (!req) {
- if (err >= 0)
- dprintk(DEBUG_ERROR,
- "unexpected response: id %d tag %d\n",
- rcall->id, rcall->tag);
-
- kfree(rcall);
- }
-
- wake_up_all(&v9ses->read_wait);
- set_current_state(TASK_INTERRUPTIBLE);
- }
-
- v9ses->transport->close(v9ses->transport);
-
- /* Inform all pending processes about the failure */
- wake_up_all(&v9ses->read_wait);
-
- if (signal_pending(current))
- complete(&v9ses->proccmpl);
-
- dprintk(DEBUG_MUX, "recvproc: end\n");
- v9ses->recvproc = NULL;
-
- return err >= 0;
-}
-
-/**
- * v9fs_mux_init - initialize multiplexer (spawn kproc)
- * @v9ses: session info structure
- * @dev_name: mount device information (to create unique kproc)
- *
- */
-
-int v9fs_mux_init(struct v9fs_session_info *v9ses, const char *dev_name)
-{
- char procname[60];
-
- strncpy(procname, dev_name, sizeof(procname));
- procname[sizeof(procname) - 1] = 0;
-
- init_waitqueue_head(&v9ses->read_wait);
- init_completion(&v9ses->fcread);
- init_completion(&v9ses->proccmpl);
- spin_lock_init(&v9ses->muxlock);
- INIT_LIST_HEAD(&v9ses->mux_fcalls);
- v9ses->recvproc = NULL;
- v9ses->curfcall = NULL;
-
- v9ses->recvproc = kthread_create(v9fs_recvproc, v9ses,
- "v9fs_recvproc %s", procname);
-
- if (IS_ERR(v9ses->recvproc)) {
- eprintk(KERN_ERR, "cannot create receiving thread\n");
- v9fs_session_close(v9ses);
- return -ECONNABORTED;
- }
-
- wake_up_process(v9ses->recvproc);
- wait_for_completion(&v9ses->proccmpl);
-
- return 0;
-}
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