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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/smbfs/request.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
Diffstat (limited to 'fs/smbfs/request.c')
-rw-r--r--fs/smbfs/request.c823
1 files changed, 823 insertions, 0 deletions
diff --git a/fs/smbfs/request.c b/fs/smbfs/request.c
new file mode 100644
index 000000000000..2d85dd7415bb
--- /dev/null
+++ b/fs/smbfs/request.c
@@ -0,0 +1,823 @@
+/*
+ *  request.c
+ *
+ *  Copyright (C) 2001 by Urban Widmark
+ *
+ *  Please add a note about your changes to smbfs in the ChangeLog file.
+ */
+
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/net.h>
+
+#include <linux/smb_fs.h>
+#include <linux/smbno.h>
+#include <linux/smb_mount.h>
+
+#include "smb_debug.h"
+#include "request.h"
+#include "proto.h"
+
+/* #define SMB_SLAB_DEBUG	(SLAB_RED_ZONE | SLAB_POISON) */
+#define SMB_SLAB_DEBUG	0
+
+#define ROUND_UP(x) (((x)+3) & ~3)
+
+/* cache for request structures */
+static kmem_cache_t *req_cachep;
+
+static int smb_request_send_req(struct smb_request *req);
+
+/*
+  /proc/slabinfo:
+  name, active, num, objsize, active_slabs, num_slaps, #pages
+*/
+
+
+int smb_init_request_cache(void)
+{
+	req_cachep = kmem_cache_create("smb_request",
+				       sizeof(struct smb_request), 0,
+				       SMB_SLAB_DEBUG | SLAB_HWCACHE_ALIGN,
+				       NULL, NULL);
+	if (req_cachep == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+void smb_destroy_request_cache(void)
+{
+	if (kmem_cache_destroy(req_cachep))
+		printk(KERN_INFO "smb_destroy_request_cache: not all structures were freed\n");
+}
+
+/*
+ * Allocate and initialise a request structure
+ */
+static struct smb_request *smb_do_alloc_request(struct smb_sb_info *server,
+						int bufsize)
+{
+	struct smb_request *req;
+	unsigned char *buf = NULL;
+
+	req = kmem_cache_alloc(req_cachep, SLAB_KERNEL);
+	VERBOSE("allocating request: %p\n", req);
+	if (!req)
+		goto out;
+
+	if (bufsize > 0) {
+		buf = smb_kmalloc(bufsize, GFP_NOFS);
+		if (!buf) {
+			kmem_cache_free(req_cachep, req);
+			return NULL;
+		}
+	}
+
+	memset(req, 0, sizeof(struct smb_request));
+	req->rq_buffer = buf;
+	req->rq_bufsize = bufsize;
+	req->rq_server = server;
+	init_waitqueue_head(&req->rq_wait);
+	INIT_LIST_HEAD(&req->rq_queue);
+	atomic_set(&req->rq_count, 1);
+
+out:
+	return req;
+}
+
+struct smb_request *smb_alloc_request(struct smb_sb_info *server, int bufsize)
+{
+	struct smb_request *req = NULL;
+
+	for (;;) {
+		atomic_inc(&server->nr_requests);
+		if (atomic_read(&server->nr_requests) <= MAX_REQUEST_HARD) {
+			req = smb_do_alloc_request(server, bufsize);
+			if (req != NULL)
+				break;
+		}
+
+#if 0
+		/*
+		 * Try to free up at least one request in order to stay
+		 * below the hard limit
+		 */
+                if (nfs_try_to_free_pages(server))
+			continue;
+
+		if (signalled() && (server->flags & NFS_MOUNT_INTR))
+			return ERR_PTR(-ERESTARTSYS);
+		current->policy = SCHED_YIELD;
+		schedule();
+#else
+		/* FIXME: we want something like nfs does above, but that
+		   requires changes to all callers and can wait. */
+		break;
+#endif
+	}
+	return req;
+}
+
+static void smb_free_request(struct smb_request *req)
+{
+	atomic_dec(&req->rq_server->nr_requests);
+	if (req->rq_buffer && !(req->rq_flags & SMB_REQ_STATIC))
+		smb_kfree(req->rq_buffer);
+	if (req->rq_trans2buffer)
+		smb_kfree(req->rq_trans2buffer);
+	kmem_cache_free(req_cachep, req);
+}
+
+/*
+ * What prevents a rget to race with a rput? The count must never drop to zero
+ * while it is in use. Only rput if it is ok that it is free'd.
+ */
+static void smb_rget(struct smb_request *req)
+{
+	atomic_inc(&req->rq_count);
+}
+void smb_rput(struct smb_request *req)
+{
+	if (atomic_dec_and_test(&req->rq_count)) {
+		list_del_init(&req->rq_queue);
+		smb_free_request(req);
+	}
+}
+
+/* setup to receive the data part of the SMB */
+static int smb_setup_bcc(struct smb_request *req)
+{
+	int result = 0;
+	req->rq_rlen = smb_len(req->rq_header) + 4 - req->rq_bytes_recvd;
+
+	if (req->rq_rlen > req->rq_bufsize) {
+		PARANOIA("Packet too large %d > %d\n",
+			 req->rq_rlen, req->rq_bufsize);
+		return -ENOBUFS;
+	}
+
+	req->rq_iov[0].iov_base = req->rq_buffer;
+	req->rq_iov[0].iov_len  = req->rq_rlen;
+	req->rq_iovlen = 1;
+
+	return result;
+}
+
+/*
+ * Prepare a "normal" request structure.
+ */
+static int smb_setup_request(struct smb_request *req)
+{
+	int len = smb_len(req->rq_header) + 4;
+	req->rq_slen = len;
+
+	/* if we expect a data part in the reply we set the iov's to read it */
+	if (req->rq_resp_bcc)
+		req->rq_setup_read = smb_setup_bcc;
+
+	/* This tries to support re-using the same request */
+	req->rq_bytes_sent = 0;
+	req->rq_rcls = 0;
+	req->rq_err = 0;
+	req->rq_errno = 0;
+	req->rq_fragment = 0;
+	if (req->rq_trans2buffer)
+		smb_kfree(req->rq_trans2buffer);
+
+	return 0;
+}
+
+/*
+ * Prepare a transaction2 request structure
+ */
+static int smb_setup_trans2request(struct smb_request *req)
+{
+	struct smb_sb_info *server = req->rq_server;
+	int mparam, mdata;
+	static unsigned char padding[4];
+
+	/* I know the following is very ugly, but I want to build the
+	   smb packet as efficiently as possible. */
+
+	const int smb_parameters = 15;
+	const int header = SMB_HEADER_LEN + 2 * smb_parameters + 2;
+	const int oparam = ROUND_UP(header + 3);
+	const int odata  = ROUND_UP(oparam + req->rq_lparm);
+	const int bcc = (req->rq_data ? odata + req->rq_ldata :
+					oparam + req->rq_lparm) - header;
+
+	if ((bcc + oparam) > server->opt.max_xmit)
+		return -ENOMEM;
+	smb_setup_header(req, SMBtrans2, smb_parameters, bcc);
+
+	/*
+	 * max parameters + max data + max setup == bufsize to make NT4 happy
+	 * and not abort the transfer or split into multiple responses. It also
+	 * makes smbfs happy as handling packets larger than the buffer size
+	 * is extra work.
+	 *
+	 * OS/2 is probably going to hate me for this ...
+	 */
+	mparam = SMB_TRANS2_MAX_PARAM;
+	mdata = req->rq_bufsize - mparam;
+
+	mdata = server->opt.max_xmit - mparam - 100;
+	if (mdata < 1024) {
+		mdata = 1024;
+		mparam = 20;
+	}
+
+#if 0
+	/* NT/win2k has ~4k max_xmit, so with this we request more than it wants
+	   to return as one SMB. Useful for testing the fragmented trans2
+	   handling. */
+	mdata = 8192;
+#endif
+
+	WSET(req->rq_header, smb_tpscnt, req->rq_lparm);
+	WSET(req->rq_header, smb_tdscnt, req->rq_ldata);
+	WSET(req->rq_header, smb_mprcnt, mparam);
+	WSET(req->rq_header, smb_mdrcnt, mdata);
+	WSET(req->rq_header, smb_msrcnt, 0);    /* max setup always 0 ? */
+	WSET(req->rq_header, smb_flags, 0);
+	DSET(req->rq_header, smb_timeout, 0);
+	WSET(req->rq_header, smb_pscnt, req->rq_lparm);
+	WSET(req->rq_header, smb_psoff, oparam - 4);
+	WSET(req->rq_header, smb_dscnt, req->rq_ldata);
+	WSET(req->rq_header, smb_dsoff, req->rq_data ? odata - 4 : 0);
+	*(req->rq_header + smb_suwcnt) = 0x01;          /* setup count */
+	*(req->rq_header + smb_suwcnt + 1) = 0x00;      /* reserved */
+	WSET(req->rq_header, smb_setup0, req->rq_trans2_command);
+
+	req->rq_iovlen = 2;
+	req->rq_iov[0].iov_base = (void *) req->rq_header;
+	req->rq_iov[0].iov_len = oparam;
+	req->rq_iov[1].iov_base = (req->rq_parm==NULL) ? padding : req->rq_parm;
+	req->rq_iov[1].iov_len = req->rq_lparm;
+	req->rq_slen = oparam + req->rq_lparm;
+
+	if (req->rq_data) {
+		req->rq_iovlen += 2;
+		req->rq_iov[2].iov_base = padding;
+		req->rq_iov[2].iov_len = odata - oparam - req->rq_lparm;
+		req->rq_iov[3].iov_base = req->rq_data;
+		req->rq_iov[3].iov_len = req->rq_ldata;
+		req->rq_slen = odata + req->rq_ldata;
+	}
+
+	/* always a data part for trans2 replies */
+	req->rq_setup_read = smb_setup_bcc;
+
+	return 0;
+}
+
+/*
+ * Add a request and tell smbiod to process it
+ */
+int smb_add_request(struct smb_request *req)
+{
+	long timeleft;
+	struct smb_sb_info *server = req->rq_server;
+	int result = 0;
+
+	smb_setup_request(req);
+	if (req->rq_trans2_command) {
+		if (req->rq_buffer == NULL) {
+			PARANOIA("trans2 attempted without response buffer!\n");
+			return -EIO;
+		}
+		result = smb_setup_trans2request(req);
+	}
+	if (result < 0)
+		return result;
+
+#ifdef SMB_DEBUG_PACKET_SIZE
+	add_xmit_stats(req);
+#endif
+
+	/* add 'req' to the queue of requests */
+	if (smb_lock_server_interruptible(server))
+		return -EINTR;
+
+	/*
+	 * Try to send the request as the process. If that fails we queue the
+	 * request and let smbiod send it later.
+	 */
+
+	/* FIXME: each server has a number on the maximum number of parallel
+	   requests. 10, 50 or so. We should not allow more requests to be
+	   active. */
+	if (server->mid > 0xf000)
+		server->mid = 0;
+	req->rq_mid = server->mid++;
+	WSET(req->rq_header, smb_mid, req->rq_mid);
+
+	result = 0;
+	if (server->state == CONN_VALID) {
+		if (list_empty(&server->xmitq))
+			result = smb_request_send_req(req);
+		if (result < 0) {
+			/* Connection lost? */
+			server->conn_error = result;
+			server->state = CONN_INVALID;
+		}
+	}
+	if (result != 1)
+		list_add_tail(&req->rq_queue, &server->xmitq);
+	smb_rget(req);
+
+	if (server->state != CONN_VALID)
+		smbiod_retry(server);
+
+	smb_unlock_server(server);
+
+	smbiod_wake_up();
+
+	timeleft = wait_event_interruptible_timeout(req->rq_wait,
+				    req->rq_flags & SMB_REQ_RECEIVED, 30*HZ);
+	if (!timeleft || signal_pending(current)) {
+		/*
+		 * On timeout or on interrupt we want to try and remove the
+		 * request from the recvq/xmitq.
+		 */
+		smb_lock_server(server);
+		if (!(req->rq_flags & SMB_REQ_RECEIVED)) {
+			list_del_init(&req->rq_queue);
+			smb_rput(req);
+		}
+		smb_unlock_server(server);
+	}
+
+	if (!timeleft) {
+		PARANOIA("request [%p, mid=%d] timed out!\n",
+			 req, req->rq_mid);
+		VERBOSE("smb_com:  %02x\n", *(req->rq_header + smb_com));
+		VERBOSE("smb_rcls: %02x\n", *(req->rq_header + smb_rcls));
+		VERBOSE("smb_flg:  %02x\n", *(req->rq_header + smb_flg));
+		VERBOSE("smb_tid:  %04x\n", WVAL(req->rq_header, smb_tid));
+		VERBOSE("smb_pid:  %04x\n", WVAL(req->rq_header, smb_pid));
+		VERBOSE("smb_uid:  %04x\n", WVAL(req->rq_header, smb_uid));
+		VERBOSE("smb_mid:  %04x\n", WVAL(req->rq_header, smb_mid));
+		VERBOSE("smb_wct:  %02x\n", *(req->rq_header + smb_wct));
+
+		req->rq_rcls = ERRSRV;
+		req->rq_err  = ERRtimeout;
+
+		/* Just in case it was "stuck" */
+		smbiod_wake_up();
+	}
+	VERBOSE("woke up, rcls=%d\n", req->rq_rcls);
+
+	if (req->rq_rcls != 0)
+		req->rq_errno = smb_errno(req);
+	if (signal_pending(current))
+		req->rq_errno = -ERESTARTSYS;
+	return req->rq_errno;
+}
+
+/*
+ * Send a request and place it on the recvq if successfully sent.
+ * Must be called with the server lock held.
+ */
+static int smb_request_send_req(struct smb_request *req)
+{
+	struct smb_sb_info *server = req->rq_server;
+	int result;
+
+	if (req->rq_bytes_sent == 0) {
+		WSET(req->rq_header, smb_tid, server->opt.tid);
+		WSET(req->rq_header, smb_pid, 1);
+		WSET(req->rq_header, smb_uid, server->opt.server_uid);
+	}
+
+	result = smb_send_request(req);
+	if (result < 0 && result != -EAGAIN)
+		goto out;
+
+	result = 0;
+	if (!(req->rq_flags & SMB_REQ_TRANSMITTED))
+		goto out;
+
+	list_del_init(&req->rq_queue);
+	list_add_tail(&req->rq_queue, &server->recvq);
+	result = 1;
+out:
+	return result;
+}
+
+/*
+ * Sends one request for this server. (smbiod)
+ * Must be called with the server lock held.
+ * Returns: <0 on error
+ *           0 if no request could be completely sent
+ *           1 if all data for one request was sent
+ */
+int smb_request_send_server(struct smb_sb_info *server)
+{
+	struct list_head *head;
+	struct smb_request *req;
+	int result;
+
+	if (server->state != CONN_VALID)
+		return 0;
+
+	/* dequeue first request, if any */
+	req = NULL;
+	head = server->xmitq.next;
+	if (head != &server->xmitq) {
+		req = list_entry(head, struct smb_request, rq_queue);
+	}
+	if (!req)
+		return 0;
+
+	result = smb_request_send_req(req);
+	if (result < 0) {
+		server->conn_error = result;
+		list_del_init(&req->rq_queue);
+		list_add(&req->rq_queue, &server->xmitq);
+		result = -EIO;
+		goto out;
+	}
+
+out:
+	return result;
+}
+
+/*
+ * Try to find a request matching this "mid". Typically the first entry will
+ * be the matching one.
+ */
+static struct smb_request *find_request(struct smb_sb_info *server, int mid)
+{
+	struct list_head *tmp;
+	struct smb_request *req = NULL;
+
+	list_for_each(tmp, &server->recvq) {
+		req = list_entry(tmp, struct smb_request, rq_queue);
+		if (req->rq_mid == mid) {
+			break;
+		}
+		req = NULL;
+	}
+
+	if (!req) {
+		VERBOSE("received reply with mid %d but no request!\n",
+			WVAL(server->header, smb_mid));
+		server->rstate = SMB_RECV_DROP;
+	}
+
+	return req;
+}
+
+/*
+ * Called when we have read the smb header and believe this is a response.
+ */
+static int smb_init_request(struct smb_sb_info *server, struct smb_request *req)
+{
+	int hdrlen, wct;
+
+	memcpy(req->rq_header, server->header, SMB_HEADER_LEN);
+
+	wct = *(req->rq_header + smb_wct);
+	if (wct > 20) {	
+		PARANOIA("wct too large, %d > 20\n", wct);
+		server->rstate = SMB_RECV_DROP;
+		return 0;
+	}
+
+	req->rq_resp_wct = wct;
+	hdrlen = SMB_HEADER_LEN + wct*2 + 2;
+	VERBOSE("header length: %d   smb_wct: %2d\n", hdrlen, wct);
+
+	req->rq_bytes_recvd = SMB_HEADER_LEN;
+	req->rq_rlen = hdrlen;
+	req->rq_iov[0].iov_base = req->rq_header;
+	req->rq_iov[0].iov_len  = hdrlen;
+	req->rq_iovlen = 1;
+	server->rstate = SMB_RECV_PARAM;
+
+#ifdef SMB_DEBUG_PACKET_SIZE
+	add_recv_stats(smb_len(server->header));
+#endif
+	return 0;
+}
+
+/*
+ * Reads the SMB parameters
+ */
+static int smb_recv_param(struct smb_sb_info *server, struct smb_request *req)
+{
+	int result;
+
+	result = smb_receive(server, req);
+	if (result < 0)
+		return result;
+	if (req->rq_bytes_recvd < req->rq_rlen)
+		return 0;
+
+	VERBOSE("result: %d   smb_bcc:  %04x\n", result,
+		WVAL(req->rq_header, SMB_HEADER_LEN +
+		     (*(req->rq_header + smb_wct) * 2)));
+
+	result = 0;
+	req->rq_iov[0].iov_base = NULL;
+	req->rq_rlen = 0;
+	if (req->rq_callback)
+		req->rq_callback(req);
+	else if (req->rq_setup_read)
+		result = req->rq_setup_read(req);
+	if (result < 0) {
+		server->rstate = SMB_RECV_DROP;
+		return result;
+	}
+
+	server->rstate = req->rq_rlen > 0 ? SMB_RECV_DATA : SMB_RECV_END;
+
+	req->rq_bytes_recvd = 0;	// recvd out of the iov
+
+	VERBOSE("rlen: %d\n", req->rq_rlen);
+	if (req->rq_rlen < 0) {
+		PARANOIA("Parameters read beyond end of packet!\n");
+		server->rstate = SMB_RECV_END;
+		return -EIO;
+	}
+	return 0;
+}
+
+/*
+ * Reads the SMB data
+ */
+static int smb_recv_data(struct smb_sb_info *server, struct smb_request *req)
+{
+	int result;
+
+	result = smb_receive(server, req);
+	if (result < 0)
+		goto out;
+	if (req->rq_bytes_recvd < req->rq_rlen)
+		goto out;
+	server->rstate = SMB_RECV_END;
+out:
+	VERBOSE("result: %d\n", result);
+	return result;
+}
+
+/*
+ * Receive a transaction2 response
+ * Return: 0 if the response has been fully read
+ *         1 if there are further "fragments" to read
+ *        <0 if there is an error
+ */
+static int smb_recv_trans2(struct smb_sb_info *server, struct smb_request *req)
+{
+	unsigned char *inbuf;
+	unsigned int parm_disp, parm_offset, parm_count, parm_tot;
+	unsigned int data_disp, data_offset, data_count, data_tot;
+	int hdrlen = SMB_HEADER_LEN + req->rq_resp_wct*2 - 2;
+
+	VERBOSE("handling trans2\n");
+
+	inbuf = req->rq_header;
+	data_tot    = WVAL(inbuf, smb_tdrcnt);
+	parm_tot    = WVAL(inbuf, smb_tprcnt);
+	parm_disp   = WVAL(inbuf, smb_prdisp);
+	parm_offset = WVAL(inbuf, smb_proff);
+	parm_count  = WVAL(inbuf, smb_prcnt);
+	data_disp   = WVAL(inbuf, smb_drdisp);
+	data_offset = WVAL(inbuf, smb_droff);
+	data_count  = WVAL(inbuf, smb_drcnt);
+
+	/* Modify offset for the split header/buffer we use */
+	if (data_count || data_offset) {
+		if (unlikely(data_offset < hdrlen))
+			goto out_bad_data;
+		else
+			data_offset -= hdrlen;
+	}
+	if (parm_count || parm_offset) {
+		if (unlikely(parm_offset < hdrlen))
+			goto out_bad_parm;
+		else
+			parm_offset -= hdrlen;
+	}
+
+	if (parm_count == parm_tot && data_count == data_tot) {
+		/*
+		 * This packet has all the trans2 data.
+		 *
+		 * We setup the request so that this will be the common
+		 * case. It may be a server error to not return a
+		 * response that fits.
+		 */
+		VERBOSE("single trans2 response  "
+			"dcnt=%u, pcnt=%u, doff=%u, poff=%u\n",
+			data_count, parm_count,
+			data_offset, parm_offset);
+		req->rq_ldata = data_count;
+		req->rq_lparm = parm_count;
+		req->rq_data = req->rq_buffer + data_offset;
+		req->rq_parm = req->rq_buffer + parm_offset;
+		if (unlikely(parm_offset + parm_count > req->rq_rlen))
+			goto out_bad_parm;
+		if (unlikely(data_offset + data_count > req->rq_rlen))
+			goto out_bad_data;
+		return 0;
+	}
+
+	VERBOSE("multi trans2 response  "
+		"frag=%d, dcnt=%u, pcnt=%u, doff=%u, poff=%u\n",
+		req->rq_fragment,
+		data_count, parm_count,
+		data_offset, parm_offset);
+
+	if (!req->rq_fragment) {
+		int buf_len;
+
+		/* We got the first trans2 fragment */
+		req->rq_fragment = 1;
+		req->rq_total_data = data_tot;
+		req->rq_total_parm = parm_tot;
+		req->rq_ldata = 0;
+		req->rq_lparm = 0;
+
+		buf_len = data_tot + parm_tot;
+		if (buf_len > SMB_MAX_PACKET_SIZE)
+			goto out_too_long;
+
+		req->rq_trans2bufsize = buf_len;
+		req->rq_trans2buffer = smb_kmalloc(buf_len, GFP_NOFS);
+		if (!req->rq_trans2buffer)
+			goto out_no_mem;
+		memset(req->rq_trans2buffer, 0, buf_len);
+
+		req->rq_parm = req->rq_trans2buffer;
+		req->rq_data = req->rq_trans2buffer + parm_tot;
+	} else if (unlikely(req->rq_total_data < data_tot ||
+			    req->rq_total_parm < parm_tot))
+		goto out_data_grew;
+
+	if (unlikely(parm_disp + parm_count > req->rq_total_parm ||
+		     parm_offset + parm_count > req->rq_rlen))
+		goto out_bad_parm;
+	if (unlikely(data_disp + data_count > req->rq_total_data ||
+		     data_offset + data_count > req->rq_rlen))
+		goto out_bad_data;
+
+	inbuf = req->rq_buffer;
+	memcpy(req->rq_parm + parm_disp, inbuf + parm_offset, parm_count);
+	memcpy(req->rq_data + data_disp, inbuf + data_offset, data_count);
+
+	req->rq_ldata += data_count;
+	req->rq_lparm += parm_count;
+
+	/*
+	 * Check whether we've received all of the data. Note that
+	 * we use the packet totals -- total lengths might shrink!
+	 */
+	if (req->rq_ldata >= data_tot && req->rq_lparm >= parm_tot) {
+		req->rq_ldata = data_tot;
+		req->rq_lparm = parm_tot;
+		return 0;
+	}
+	return 1;
+
+out_too_long:
+	printk(KERN_ERR "smb_trans2: data/param too long, data=%u, parm=%u\n",
+		data_tot, parm_tot);
+	goto out_EIO;
+out_no_mem:
+	printk(KERN_ERR "smb_trans2: couldn't allocate data area of %d bytes\n",
+	       req->rq_trans2bufsize);
+	req->rq_errno = -ENOMEM;
+	goto out;
+out_data_grew:
+	printk(KERN_ERR "smb_trans2: data/params grew!\n");
+	goto out_EIO;
+out_bad_parm:
+	printk(KERN_ERR "smb_trans2: invalid parms, disp=%u, cnt=%u, tot=%u, ofs=%u\n",
+	       parm_disp, parm_count, parm_tot, parm_offset);
+	goto out_EIO;
+out_bad_data:
+	printk(KERN_ERR "smb_trans2: invalid data, disp=%u, cnt=%u, tot=%u, ofs=%u\n",
+	       data_disp, data_count, data_tot, data_offset);
+out_EIO:
+	req->rq_errno = -EIO;
+out:
+	return req->rq_errno;
+}
+
+/*
+ * State machine for receiving responses. We handle the fact that we can't
+ * read the full response in one try by having states telling us how much we
+ * have read.
+ *
+ * Must be called with the server lock held (only called from smbiod).
+ *
+ * Return: <0 on error
+ */
+int smb_request_recv(struct smb_sb_info *server)
+{
+	struct smb_request *req = NULL;
+	int result = 0;
+
+	if (smb_recv_available(server) <= 0)
+		return 0;
+
+	VERBOSE("state: %d\n", server->rstate);
+	switch (server->rstate) {
+	case SMB_RECV_DROP:
+		result = smb_receive_drop(server);
+		if (result < 0)
+			break;
+		if (server->rstate == SMB_RECV_DROP)
+			break;
+		server->rstate = SMB_RECV_START;
+		/* fallthrough */
+	case SMB_RECV_START:
+		server->smb_read = 0;
+		server->rstate = SMB_RECV_HEADER;
+		/* fallthrough */
+	case SMB_RECV_HEADER:
+		result = smb_receive_header(server);
+		if (result < 0)
+			break;
+		if (server->rstate == SMB_RECV_HEADER)
+			break;
+		if (! (*(server->header + smb_flg) & SMB_FLAGS_REPLY) ) {
+			server->rstate = SMB_RECV_REQUEST;
+			break;
+		}
+		if (server->rstate != SMB_RECV_HCOMPLETE)
+			break;
+		/* fallthrough */
+	case SMB_RECV_HCOMPLETE:
+		req = find_request(server, WVAL(server->header, smb_mid));
+		if (!req)
+			break;
+		smb_init_request(server, req);
+		req->rq_rcls = *(req->rq_header + smb_rcls);
+		req->rq_err  = WVAL(req->rq_header, smb_err);
+		if (server->rstate != SMB_RECV_PARAM)
+			break;
+		/* fallthrough */
+	case SMB_RECV_PARAM:
+		if (!req)
+			req = find_request(server,WVAL(server->header,smb_mid));
+		if (!req)
+			break;
+		result = smb_recv_param(server, req);
+		if (result < 0)
+			break;
+		if (server->rstate != SMB_RECV_DATA)
+			break;
+		/* fallthrough */
+	case SMB_RECV_DATA:
+		if (!req)
+			req = find_request(server,WVAL(server->header,smb_mid));
+		if (!req)
+			break;
+		result = smb_recv_data(server, req);
+		if (result < 0)
+			break;
+		break;
+
+		/* We should never be called with any of these states */
+	case SMB_RECV_END:
+	case SMB_RECV_REQUEST:
+		server->rstate = SMB_RECV_END;
+		break;
+	}
+
+	if (result < 0) {
+		/* We saw an error */
+		return result;
+	}
+
+	if (server->rstate != SMB_RECV_END)
+		return 0;
+
+	result = 0;
+	if (req->rq_trans2_command && req->rq_rcls == SUCCESS)
+		result = smb_recv_trans2(server, req);
+
+	/*
+	 * Response completely read. Drop any extra bytes sent by the server.
+	 * (Yes, servers sometimes add extra bytes to responses)
+	 */
+	VERBOSE("smb_len: %d   smb_read: %d\n",
+		server->smb_len, server->smb_read);
+	if (server->smb_read < server->smb_len)
+		smb_receive_drop(server);
+
+	server->rstate = SMB_RECV_START;
+
+	if (!result) {
+		list_del_init(&req->rq_queue);
+		req->rq_flags |= SMB_REQ_RECEIVED;
+		smb_rput(req);
+		wake_up_interruptible(&req->rq_wait);
+	}
+	return 0;
+}