1 files changed, 123 insertions, 139 deletions

diff --git a/net/9p/client.c b/net/9p/client.c
index e86a9bea1d16..6f4c4c88db84 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -34,6 +34,7 @@
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/uaccess.h>
+#include <linux/uio.h>
 #include <net/9p/9p.h>
 #include <linux/parser.h>
 #include <net/9p/client.h>
@@ -555,7 +556,7 @@ out_err:
  */
 
 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
-			      char *uidata, int in_hdrlen, int kern_buf)
+			      struct iov_iter *uidata, int in_hdrlen)
 {
 	int err;
 	int ecode;
@@ -591,16 +592,11 @@ static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 		ename = &req->rc->sdata[req->rc->offset];
 		if (len > inline_len) {
 			/* We have error in external buffer */
-			if (kern_buf) {
-				memcpy(ename + inline_len, uidata,
-				       len - inline_len);
-			} else {
-				err = copy_from_user(ename + inline_len,
-						     uidata, len - inline_len);
-				if (err) {
-					err = -EFAULT;
-					goto out_err;
-				}
+			err = copy_from_iter(ename + inline_len,
+					     len - inline_len, uidata);
+			if (err != len - inline_len) {
+				err = -EFAULT;
+				goto out_err;
 			}
 		}
 		ename = NULL;
@@ -806,8 +802,8 @@ reterr:
  * p9_client_zc_rpc - issue a request and wait for a response
  * @c: client session
  * @type: type of request
- * @uidata: user bffer that should be ued for zero copy read
- * @uodata: user buffer that shoud be user for zero copy write
+ * @uidata: destination for zero copy read
+ * @uodata: source for zero copy write
  * @inlen: read buffer size
  * @olen: write buffer size
  * @hdrlen: reader header size, This is the size of response protocol data
@@ -816,9 +812,10 @@ reterr:
  * Returns request structure (which client must free using p9_free_req)
  */
 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
-					 char *uidata, char *uodata,
+					 struct iov_iter *uidata,
+					 struct iov_iter *uodata,
 					 int inlen, int olen, int in_hdrlen,
-					 int kern_buf, const char *fmt, ...)
+					 const char *fmt, ...)
 {
 	va_list ap;
 	int sigpending, err;
@@ -841,12 +838,8 @@ static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 	} else
 		sigpending = 0;
 
-	/* If we are called with KERNEL_DS force kern_buf */
-	if (segment_eq(get_fs(), KERNEL_DS))
-		kern_buf = 1;
-
 	err = c->trans_mod->zc_request(c, req, uidata, uodata,
-				       inlen, olen, in_hdrlen, kern_buf);
+				       inlen, olen, in_hdrlen);
 	if (err < 0) {
 		if (err == -EIO)
 			c->status = Disconnected;
@@ -876,7 +869,7 @@ static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 	if (err < 0)
 		goto reterr;
 
-	err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
+	err = p9_check_zc_errors(c, req, uidata, in_hdrlen);
 	trace_9p_client_res(c, type, req->rc->tag, err);
 	if (!err)
 		return req;
@@ -1123,6 +1116,7 @@ struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
 		fid = NULL;
 		goto error;
 	}
+	fid->uid = n_uname;
 
 	req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
 			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
@@ -1541,142 +1535,128 @@ error:
 EXPORT_SYMBOL(p9_client_unlinkat);
 
 int
-p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
-								u32 count)
+p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
 {
-	char *dataptr;
-	int kernel_buf = 0;
+	struct p9_client *clnt = fid->clnt;
 	struct p9_req_t *req;
-	struct p9_client *clnt;
-	int err, rsize, non_zc = 0;
-
+	int total = 0;
 
 	p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
-		   fid->fid, (unsigned long long) offset, count);
-	err = 0;
-	clnt = fid->clnt;
-
-	rsize = fid->iounit;
-	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
-		rsize = clnt->msize - P9_IOHDRSZ;
-
-	if (count < rsize)
-		rsize = count;
-
-	/* Don't bother zerocopy for small IO (< 1024) */
-	if (clnt->trans_mod->zc_request && rsize > 1024) {
-		char *indata;
-		if (data) {
-			kernel_buf = 1;
-			indata = data;
-		} else
-			indata = (__force char *)udata;
-		/*
-		 * response header len is 11
-		 * PDU Header(7) + IO Size (4)
-		 */
-		req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
-				       11, kernel_buf, "dqd", fid->fid,
-				       offset, rsize);
-	} else {
-		non_zc = 1;
-		req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
-				    rsize);
-	}
-	if (IS_ERR(req)) {
-		err = PTR_ERR(req);
-		goto error;
-	}
+		   fid->fid, (unsigned long long) offset, (int)iov_iter_count(to));
+
+	while (iov_iter_count(to)) {
+		int count = iov_iter_count(to);
+		int rsize, non_zc = 0;
+		char *dataptr;
+			
+		rsize = fid->iounit;
+		if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
+			rsize = clnt->msize - P9_IOHDRSZ;
+
+		if (count < rsize)
+			rsize = count;
+
+		/* Don't bother zerocopy for small IO (< 1024) */
+		if (clnt->trans_mod->zc_request && rsize > 1024) {
+			/*
+			 * response header len is 11
+			 * PDU Header(7) + IO Size (4)
+			 */
+			req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
+					       0, 11, "dqd", fid->fid,
+					       offset, rsize);
+		} else {
+			non_zc = 1;
+			req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
+					    rsize);
+		}
+		if (IS_ERR(req)) {
+			*err = PTR_ERR(req);
+			break;
+		}
 
-	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
-	if (err) {
-		trace_9p_protocol_dump(clnt, req->rc);
-		goto free_and_error;
-	}
+		*err = p9pdu_readf(req->rc, clnt->proto_version,
+				   "D", &count, &dataptr);
+		if (*err) {
+			trace_9p_protocol_dump(clnt, req->rc);
+			p9_free_req(clnt, req);
+			break;
+		}
 
-	p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
+		p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
+		if (!count) {
+			p9_free_req(clnt, req);
+			break;
+		}
 
-	if (non_zc) {
-		if (data) {
-			memmove(data, dataptr, count);
-		} else {
-			err = copy_to_user(udata, dataptr, count);
-			if (err) {
-				err = -EFAULT;
-				goto free_and_error;
+		if (non_zc) {
+			int n = copy_to_iter(dataptr, count, to);
+			total += n;
+			offset += n;
+			if (n != count) {
+				*err = -EFAULT;
+				p9_free_req(clnt, req);
+				break;
 			}
+		} else {
+			iov_iter_advance(to, count);
+			total += count;
+			offset += count;
 		}
+		p9_free_req(clnt, req);
 	}
-	p9_free_req(clnt, req);
-	return count;
-
-free_and_error:
-	p9_free_req(clnt, req);
-error:
-	return err;
+	return total;
 }
 EXPORT_SYMBOL(p9_client_read);
 
 int
-p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
-							u64 offset, u32 count)
+p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
 {
-	int err, rsize;
-	int kernel_buf = 0;
-	struct p9_client *clnt;
+	struct p9_client *clnt = fid->clnt;
 	struct p9_req_t *req;
+	int total = 0;
+
+	p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
+				fid->fid, (unsigned long long) offset,
+				iov_iter_count(from));
+
+	while (iov_iter_count(from)) {
+		int count = iov_iter_count(from);
+		int rsize = fid->iounit;
+		if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
+			rsize = clnt->msize - P9_IOHDRSZ;
+
+		if (count < rsize)
+			rsize = count;
+
+		/* Don't bother zerocopy for small IO (< 1024) */
+		if (clnt->trans_mod->zc_request && rsize > 1024) {
+			req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
+					       rsize, P9_ZC_HDR_SZ, "dqd",
+					       fid->fid, offset, rsize);
+		} else {
+			req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
+						    offset, rsize, from);
+		}
+		if (IS_ERR(req)) {
+			*err = PTR_ERR(req);
+			break;
+		}
 
-	p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
-				fid->fid, (unsigned long long) offset, count);
-	err = 0;
-	clnt = fid->clnt;
-
-	rsize = fid->iounit;
-	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
-		rsize = clnt->msize - P9_IOHDRSZ;
+		*err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
+		if (*err) {
+			trace_9p_protocol_dump(clnt, req->rc);
+			p9_free_req(clnt, req);
+		}
 
-	if (count < rsize)
-		rsize = count;
+		p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
 
-	/* Don't bother zerocopy for small IO (< 1024) */
-	if (clnt->trans_mod->zc_request && rsize > 1024) {
-		char *odata;
-		if (data) {
-			kernel_buf = 1;
-			odata = data;
-		} else
-			odata = (char *)udata;
-		req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
-				       P9_ZC_HDR_SZ, kernel_buf, "dqd",
-				       fid->fid, offset, rsize);
-	} else {
-		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 = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
-	if (err) {
-		trace_9p_protocol_dump(clnt, req->rc);
-		goto free_and_error;
+		p9_free_req(clnt, req);
+		iov_iter_advance(from, count);
+		total += count;
+		offset += count;
 	}
-
-	p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
-
-	p9_free_req(clnt, req);
-	return count;
-
-free_and_error:
-	p9_free_req(clnt, req);
-error:
-	return err;
+	return total;
 }
 EXPORT_SYMBOL(p9_client_write);
 
@@ -2068,6 +2048,10 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 	char *dataptr;
+	struct kvec kv = {.iov_base = data, .iov_len = count};
+	struct iov_iter to;
+
+	iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
 
 	p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
 				fid->fid, (unsigned long long) offset, count);
@@ -2088,8 +2072,8 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
 		 * response header len is 11
 		 * PDU Header(7) + IO Size (4)
 		 */
-		req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
-				       11, 1, "dqd", fid->fid, offset, rsize);
+		req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
+				       11, "dqd", fid->fid, offset, rsize);
 	} else {
 		non_zc = 1;
 		req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,