[linux-2.6-block.git] / net / 9p / protocol.c

/*
 * net/9p/protocol.c
 *
 * 9P Protocol Support Code
 *
 *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
 *
 *  Base on code from Anthony Liguori <aliguori@us.ibm.com>
 *  Copyright (C) 2008 by IBM, Corp.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  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/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include "protocol.h"

#include <trace/events/9p.h>

static int
p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);

void p9stat_free(struct p9_wstat *stbuf)
{
	kfree(stbuf->name);
	kfree(stbuf->uid);
	kfree(stbuf->gid);
	kfree(stbuf->muid);
	kfree(stbuf->extension);
}
EXPORT_SYMBOL(p9stat_free);

size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size)
{
	size_t len = min(pdu->size - pdu->offset, size);
	memcpy(data, &pdu->sdata[pdu->offset], len);
	pdu->offset += len;
	return size - len;
}

static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size)
{
	size_t len = min(pdu->capacity - pdu->size, size);
	memcpy(&pdu->sdata[pdu->size], data, len);
	pdu->size += len;
	return size - len;
}

static size_t
pdu_write_u(struct p9_fcall *pdu, const char __user *udata, size_t size)
{
	size_t len = min(pdu->capacity - pdu->size, size);
	if (copy_from_user(&pdu->sdata[pdu->size], udata, len))
		len = 0;

	pdu->size += len;
	return size - len;
}

/*
	b - int8_t
	w - int16_t
	d - int32_t
	q - int64_t
	s - string
	S - stat
	Q - qid
	D - data blob (int32_t size followed by void *, results are not freed)
	T - array of strings (int16_t count, followed by strings)
	R - array of qids (int16_t count, followed by qids)
	A - stat for 9p2000.L (p9_stat_dotl)
	? - if optional = 1, continue parsing
*/

static int
p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
	va_list ap)
{
	const char *ptr;
	int errcode = 0;

	for (ptr = fmt; *ptr; ptr++) {
		switch (*ptr) {
		case 'b':{
				int8_t *val = va_arg(ap, int8_t *);
				if (pdu_read(pdu, val, sizeof(*val))) {
					errcode = -EFAULT;
					break;
				}
			}
			break;
		case 'w':{
				int16_t *val = va_arg(ap, int16_t *);
				__le16 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*val = le16_to_cpu(le_val);
			}
			break;
		case 'd':{
				int32_t *val = va_arg(ap, int32_t *);
				__le32 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*val = le32_to_cpu(le_val);
			}
			break;
		case 'q':{
				int64_t *val = va_arg(ap, int64_t *);
				__le64 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*val = le64_to_cpu(le_val);
			}
			break;
		case 's':{
				char **sptr = va_arg(ap, char **);
				uint16_t len;

				errcode = p9pdu_readf(pdu, proto_version,
								"w", &len);
				if (errcode)
					break;

				*sptr = kmalloc(len + 1, GFP_NOFS);
				if (*sptr == NULL) {
					errcode = -EFAULT;
					break;
				}
				if (pdu_read(pdu, *sptr, len)) {
					errcode = -EFAULT;
					kfree(*sptr);
					*sptr = NULL;
				} else
					(*sptr)[len] = 0;
			}
			break;
		case 'Q':{
				struct p9_qid *qid =
				    va_arg(ap, struct p9_qid *);

				errcode = p9pdu_readf(pdu, proto_version, "bdq",
						      &qid->type, &qid->version,
						      &qid->path);
			}
			break;
		case 'S':{
				struct p9_wstat *stbuf =
				    va_arg(ap, struct p9_wstat *);

				memset(stbuf, 0, sizeof(struct p9_wstat));
				stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
									-1;
				errcode =
				    p9pdu_readf(pdu, proto_version,
						"wwdQdddqssss?sddd",
						&stbuf->size, &stbuf->type,
						&stbuf->dev, &stbuf->qid,
						&stbuf->mode, &stbuf->atime,
						&stbuf->mtime, &stbuf->length,
						&stbuf->name, &stbuf->uid,
						&stbuf->gid, &stbuf->muid,
						&stbuf->extension,
						&stbuf->n_uid, &stbuf->n_gid,
						&stbuf->n_muid);
				if (errcode)
					p9stat_free(stbuf);
			}
			break;
		case 'D':{
				uint32_t *count = va_arg(ap, uint32_t *);
				void **data = va_arg(ap, void **);

				errcode =
				    p9pdu_readf(pdu, proto_version, "d", count);
				if (!errcode) {
					*count =
					    min_t(uint32_t, *count,
						  pdu->size - pdu->offset);
					*data = &pdu->sdata[pdu->offset];
				}
			}
			break;
		case 'T':{
				uint16_t *nwname = va_arg(ap, uint16_t *);
				char ***wnames = va_arg(ap, char ***);

				errcode = p9pdu_readf(pdu, proto_version,
								"w", nwname);
				if (!errcode) {
					*wnames =
					    kmalloc(sizeof(char *) * *nwname,
						    GFP_NOFS);
					if (!*wnames)
						errcode = -ENOMEM;
				}

				if (!errcode) {
					int i;

					for (i = 0; i < *nwname; i++) {
						errcode =
						    p9pdu_readf(pdu,
								proto_version,
								"s",
								&(*wnames)[i]);
						if (errcode)
							break;
					}
				}

				if (errcode) {
					if (*wnames) {
						int i;

						for (i = 0; i < *nwname; i++)
							kfree((*wnames)[i]);
					}
					kfree(*wnames);
					*wnames = NULL;
				}
			}
			break;
		case 'R':{
				int16_t *nwqid = va_arg(ap, int16_t *);
				struct p9_qid **wqids =
				    va_arg(ap, struct p9_qid **);

				*wqids = NULL;

				errcode =
				    p9pdu_readf(pdu, proto_version, "w", nwqid);
				if (!errcode) {
					*wqids =
					    kmalloc(*nwqid *
						    sizeof(struct p9_qid),
						    GFP_NOFS);
					if (*wqids == NULL)
						errcode = -ENOMEM;
				}

				if (!errcode) {
					int i;

					for (i = 0; i < *nwqid; i++) {
						errcode =
						    p9pdu_readf(pdu,
								proto_version,
								"Q",
								&(*wqids)[i]);
						if (errcode)
							break;
					}
				}

				if (errcode) {
					kfree(*wqids);
					*wqids = NULL;
				}
			}
			break;
		case 'A': {
				struct p9_stat_dotl *stbuf =
				    va_arg(ap, struct p9_stat_dotl *);

				memset(stbuf, 0, sizeof(struct p9_stat_dotl));
				errcode =
				    p9pdu_readf(pdu, proto_version,
					"qQdddqqqqqqqqqqqqqqq",
					&stbuf->st_result_mask,
					&stbuf->qid,
					&stbuf->st_mode,
					&stbuf->st_uid, &stbuf->st_gid,
					&stbuf->st_nlink,
					&stbuf->st_rdev, &stbuf->st_size,
					&stbuf->st_blksize, &stbuf->st_blocks,
					&stbuf->st_atime_sec,
					&stbuf->st_atime_nsec,
					&stbuf->st_mtime_sec,
					&stbuf->st_mtime_nsec,
					&stbuf->st_ctime_sec,
					&stbuf->st_ctime_nsec,
					&stbuf->st_btime_sec,
					&stbuf->st_btime_nsec,
					&stbuf->st_gen,
					&stbuf->st_data_version);
			}
			break;
		case '?':
			if ((proto_version != p9_proto_2000u) &&
				(proto_version != p9_proto_2000L))
				return 0;
			break;
		default:
			BUG();
			break;
		}

		if (errcode)
			break;
	}

	return errcode;
}

int
p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
	va_list ap)
{
	const char *ptr;
	int errcode = 0;

	for (ptr = fmt; *ptr; ptr++) {
		switch (*ptr) {
		case 'b':{
				int8_t val = va_arg(ap, int);
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 'w':{
				__le16 val = cpu_to_le16(va_arg(ap, int));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 'd':{
				__le32 val = cpu_to_le32(va_arg(ap, int32_t));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 'q':{
				__le64 val = cpu_to_le64(va_arg(ap, int64_t));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 's':{
				const char *sptr = va_arg(ap, const char *);
				uint16_t len = 0;
				if (sptr)
					len = min_t(uint16_t, strlen(sptr),
								USHRT_MAX);

				errcode = p9pdu_writef(pdu, proto_version,
								"w", len);
				if (!errcode && pdu_write(pdu, sptr, len))
					errcode = -EFAULT;
			}
			break;
		case 'Q':{
				const struct p9_qid *qid =
				    va_arg(ap, const struct p9_qid *);
				errcode =
				    p9pdu_writef(pdu, proto_version, "bdq",
						 qid->type, qid->version,
						 qid->path);
			} break;
		case 'S':{
				const struct p9_wstat *stbuf =
				    va_arg(ap, const struct p9_wstat *);
				errcode =
				    p9pdu_writef(pdu, proto_version,
						 "wwdQdddqssss?sddd",
						 stbuf->size, stbuf->type,
						 stbuf->dev, &stbuf->qid,
						 stbuf->mode, stbuf->atime,
						 stbuf->mtime, stbuf->length,
						 stbuf->name, stbuf->uid,
						 stbuf->gid, stbuf->muid,
						 stbuf->extension, stbuf->n_uid,
						 stbuf->n_gid, stbuf->n_muid);
			} break;
		case 'D':{
				uint32_t count = va_arg(ap, uint32_t);
				const void *data = va_arg(ap, const void *);

				errcode = p9pdu_writef(pdu, proto_version, "d",
									count);
				if (!errcode && pdu_write(pdu, data, count))
					errcode = -EFAULT;
			}
			break;
		case 'U':{
				int32_t count = va_arg(ap, int32_t);
				const char __user *udata =
						va_arg(ap, const void __user *);
				errcode = p9pdu_writef(pdu, proto_version, "d",
									count);
				if (!errcode && pdu_write_u(pdu, udata, count))
					errcode = -EFAULT;
			}
			break;
		case 'T':{
				uint16_t nwname = va_arg(ap, int);
				const char **wnames = va_arg(ap, const char **);

				errcode = p9pdu_writef(pdu, proto_version, "w",
									nwname);
				if (!errcode) {
					int i;

					for (i = 0; i < nwname; i++) {
						errcode =
						    p9pdu_writef(pdu,
								proto_version,
								 "s",
								 wnames[i]);
						if (errcode)
							break;
					}
				}
			}
			break;
		case 'R':{
				int16_t nwqid = va_arg(ap, int);
				struct p9_qid *wqids =
				    va_arg(ap, struct p9_qid *);

				errcode = p9pdu_writef(pdu, proto_version, "w",
									nwqid);
				if (!errcode) {
					int i;

					for (i = 0; i < nwqid; i++) {
						errcode =
						    p9pdu_writef(pdu,
								proto_version,
								 "Q",
								 &wqids[i]);
						if (errcode)
							break;
					}
				}
			}
			break;
		case 'I':{
				struct p9_iattr_dotl *p9attr = va_arg(ap,
							struct p9_iattr_dotl *);

				errcode = p9pdu_writef(pdu, proto_version,
							"ddddqqqqq",
							p9attr->valid,
							p9attr->mode,
							p9attr->uid,
							p9attr->gid,
							p9attr->size,
							p9attr->atime_sec,
							p9attr->atime_nsec,
							p9attr->mtime_sec,
							p9attr->mtime_nsec);
			}
			break;
		case '?':
			if ((proto_version != p9_proto_2000u) &&
				(proto_version != p9_proto_2000L))
				return 0;
			break;
		default:
			BUG();
			break;
		}

		if (errcode)
			break;
	}

	return errcode;
}

int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
{
	va_list ap;
	int ret;

	va_start(ap, fmt);
	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
	va_end(ap);

	return ret;
}

static int
p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
{
	va_list ap;
	int ret;

	va_start(ap, fmt);
	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
	va_end(ap);

	return ret;
}

int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
{
	struct p9_fcall fake_pdu;
	int ret;

	fake_pdu.size = len;
	fake_pdu.capacity = len;
	fake_pdu.sdata = buf;
	fake_pdu.offset = 0;

	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
	if (ret) {
		p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
		trace_9p_protocol_dump(clnt, &fake_pdu);
	}

	return ret;
}
EXPORT_SYMBOL(p9stat_read);

int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
{
	pdu->id = type;
	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
}

int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu)
{
	int size = pdu->size;
	int err;

	pdu->size = 0;
	err = p9pdu_writef(pdu, 0, "d", size);
	pdu->size = size;

	trace_9p_protocol_dump(clnt, pdu);
	p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
		 pdu->size, pdu->id, pdu->tag);

	return err;
}

void p9pdu_reset(struct p9_fcall *pdu)
{
	pdu->offset = 0;
	pdu->size = 0;
}

int p9dirent_read(struct p9_client *clnt, char *buf, int len,
		  struct p9_dirent *dirent)
{
	struct p9_fcall fake_pdu;
	int ret;
	char *nameptr;

	fake_pdu.size = len;
	fake_pdu.capacity = len;
	fake_pdu.sdata = buf;
	fake_pdu.offset = 0;

	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
			  &dirent->d_off, &dirent->d_type, &nameptr);
	if (ret) {
		p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
		trace_9p_protocol_dump(clnt, &fake_pdu);
		goto out;
	}

	strcpy(dirent->d_name, nameptr);
	kfree(nameptr);

out:
	return fake_pdu.offset;
}
EXPORT_SYMBOL(p9dirent_read);
Commit	Line	Data
ace51c4d EVH	1	/*
	2	* net/9p/protocol.c
	3	*
	4	* 9P Protocol Support Code
	5	*
	6	* Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
	7	*
	8	* Base on code from Anthony Liguori <aliguori@us.ibm.com>
	9	* Copyright (C) 2008 by IBM, Corp.
	10	*
	11	* This program is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License version 2
	13	* as published by the Free Software Foundation.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to:
	22	* Free Software Foundation
	23	* 51 Franklin Street, Fifth Floor
	24	* Boston, MA 02111-1301 USA
	25	*
	26	*/
	27
	28	#include <linux/module.h>
	29	#include <linux/errno.h>
01b0c5cf	30	#include <linux/kernel.h>
51a87c55	31	#include <linux/uaccess.h>
5a0e3ad6	32	#include <linux/slab.h>
e7f4b8f1	33	#include <linux/sched.h>
01b0c5cf	34	#include <linux/stddef.h>
beeebc92	35	#include <linux/types.h>
ace51c4d EVH	36	#include <net/9p/9p.h>
	37	#include <net/9p/client.h>
	38	#include "protocol.h"
	39
348b5901 AK	40	#include <trace/events/9p.h>
348b5901 AK	41
ace51c4d	42	static int
342fee1d	43	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...);
ace51c4d EVH	44
	45	void p9stat_free(struct p9_wstat *stbuf)
	46	{
	47	kfree(stbuf->name);
	48	kfree(stbuf->uid);
	49	kfree(stbuf->gid);
	50	kfree(stbuf->muid);
	51	kfree(stbuf->extension);
	52	}
	53	EXPORT_SYMBOL(p9stat_free);
	54
abfa034e	55	size_t pdu_read(struct p9_fcall pdu, void data, size_t size)
ace51c4d	56	{
01b0c5cf	57	size_t len = min(pdu->size - pdu->offset, size);
ace51c4d EVH	58	memcpy(data, &pdu->sdata[pdu->offset], len);
	59	pdu->offset += len;
	60	return size - len;
	61	}
	62
	63	static size_t pdu_write(struct p9_fcall pdu, const void data, size_t size)
	64	{
01b0c5cf	65	size_t len = min(pdu->capacity - pdu->size, size);
ace51c4d EVH	66	memcpy(&pdu->sdata[pdu->size], data, len);
	67	pdu->size += len;
	68	return size - len;
	69	}
	70
51a87c55 EVH	71	static size_t
	72	pdu_write_u(struct p9_fcall pdu, const char __user udata, size_t size)
	73	{
01b0c5cf	74	size_t len = min(pdu->capacity - pdu->size, size);
7b3bb3fe AK	75	if (copy_from_user(&pdu->sdata[pdu->size], udata, len))
7b3bb3fe AK	76	len = 0;
51a87c55 EVH	77
	78	pdu->size += len;
	79	return size - len;
	80	}
	81
ace51c4d EVH	82	/*
	83	b - int8_t
	84	w - int16_t
	85	d - int32_t
	86	q - int64_t
	87	s - string
	88	S - stat
	89	Q - qid
	90	D - data blob (int32_t size followed by void *, results are not freed)
	91	T - array of strings (int16_t count, followed by strings)
	92	R - array of qids (int16_t count, followed by qids)
f0853122	93	A - stat for 9p2000.L (p9_stat_dotl)
ace51c4d EVH	94	? - if optional = 1, continue parsing
	95	*/
	96
	97	static int
342fee1d SK	98	p9pdu_vreadf(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	99	va_list ap)
ace51c4d EVH	100	{
	101	const char *ptr;
	102	int errcode = 0;
	103
	104	for (ptr = fmt; *ptr; ptr++) {
	105	switch (*ptr) {
	106	case 'b':{
	107	int8_t val = va_arg(ap, int8_t );
	108	if (pdu_read(pdu, val, sizeof(*val))) {
	109	errcode = -EFAULT;
	110	break;
	111	}
	112	}
	113	break;
	114	case 'w':{
	115	int16_t val = va_arg(ap, int16_t );
beeebc92 EVH	116	__le16 le_val;
beeebc92 EVH	117	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	118	errcode = -EFAULT;
	119	break;
	120	}
beeebc92	121	*val = le16_to_cpu(le_val);
ace51c4d EVH	122	}
	123	break;
	124	case 'd':{
	125	int32_t val = va_arg(ap, int32_t );
beeebc92 EVH	126	__le32 le_val;
beeebc92 EVH	127	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	128	errcode = -EFAULT;
	129	break;
	130	}
beeebc92	131	*val = le32_to_cpu(le_val);
ace51c4d EVH	132	}
	133	break;
	134	case 'q':{
	135	int64_t val = va_arg(ap, int64_t );
beeebc92 EVH	136	__le64 le_val;
beeebc92 EVH	137	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	138	errcode = -EFAULT;
	139	break;
	140	}
beeebc92	141	*val = le64_to_cpu(le_val);
ace51c4d EVH	142	}
	143	break;
	144	case 's':{
e45c5405	145	char sptr = va_arg(ap, char );
219fd58b	146	uint16_t len;
ace51c4d	147
342fee1d SK	148	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	149	"w", &len);
ace51c4d EVH	150	if (errcode)
	151	break;
	152
eeff66ef	153	*sptr = kmalloc(len + 1, GFP_NOFS);
e45c5405	154	if (*sptr == NULL) {
ace51c4d EVH	155	errcode = -EFAULT;
	156	break;
	157	}
219fd58b	158	if (pdu_read(pdu, *sptr, len)) {
ace51c4d	159	errcode = -EFAULT;
e45c5405 EVH	160	kfree(*sptr);
e45c5405 EVH	161	*sptr = NULL;
ace51c4d	162	} else
219fd58b	163	(*sptr)[len] = 0;
ace51c4d EVH	164	}
	165	break;
	166	case 'Q':{
	167	struct p9_qid *qid =
	168	va_arg(ap, struct p9_qid *);
	169
342fee1d	170	errcode = p9pdu_readf(pdu, proto_version, "bdq",
ace51c4d EVH	171	&qid->type, &qid->version,
	172	&qid->path);
	173	}
	174	break;
	175	case 'S':{
	176	struct p9_wstat *stbuf =
	177	va_arg(ap, struct p9_wstat *);
	178
f0a0ac2e	179	memset(stbuf, 0, sizeof(struct p9_wstat));
ace51c4d	180	stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
f0a0ac2e	181	-1;
ace51c4d	182	errcode =
342fee1d	183	p9pdu_readf(pdu, proto_version,
ace51c4d EVH	184	"wwdQdddqssss?sddd",
	185	&stbuf->size, &stbuf->type,
	186	&stbuf->dev, &stbuf->qid,
	187	&stbuf->mode, &stbuf->atime,
	188	&stbuf->mtime, &stbuf->length,
	189	&stbuf->name, &stbuf->uid,
	190	&stbuf->gid, &stbuf->muid,
	191	&stbuf->extension,
	192	&stbuf->n_uid, &stbuf->n_gid,
	193	&stbuf->n_muid);
	194	if (errcode)
	195	p9stat_free(stbuf);
	196	}
	197	break;
	198	case 'D':{
219fd58b	199	uint32_t count = va_arg(ap, uint32_t );
ace51c4d EVH	200	void data = va_arg(ap, void );
	201
	202	errcode =
342fee1d	203	p9pdu_readf(pdu, proto_version, "d", count);
ace51c4d EVH	204	if (!errcode) {
ace51c4d EVH	205	*count =
219fd58b	206	min_t(uint32_t, *count,
01b0c5cf	207	pdu->size - pdu->offset);
ace51c4d EVH	208	*data = &pdu->sdata[pdu->offset];
	209	}
	210	}
	211	break;
	212	case 'T':{
b76225e2	213	uint16_t nwname = va_arg(ap, uint16_t );
ace51c4d EVH	214	char *wnames = va_arg(ap, char *);
ace51c4d EVH	215
342fee1d SK	216	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	217	"w", nwname);
ace51c4d EVH	218	if (!errcode) {
	219	*wnames =
	220	kmalloc(sizeof(char ) *nwname,
eeff66ef	221	GFP_NOFS);
ace51c4d EVH	222	if (!*wnames)
	223	errcode = -ENOMEM;
	224	}
	225
	226	if (!errcode) {
	227	int i;
	228
	229	for (i = 0; i < *nwname; i++) {
	230	errcode =
342fee1d SK	231	p9pdu_readf(pdu,
342fee1d SK	232	proto_version,
ace51c4d EVH	233	"s",
	234	&(*wnames)[i]);
	235	if (errcode)
	236	break;
	237	}
	238	}
	239
	240	if (errcode) {
	241	if (*wnames) {
	242	int i;
	243
	244	for (i = 0; i < *nwname; i++)
	245	kfree((*wnames)[i]);
	246	}
	247	kfree(*wnames);
	248	*wnames = NULL;
	249	}
	250	}
	251	break;
	252	case 'R':{
	253	int16_t nwqid = va_arg(ap, int16_t );
	254	struct p9_qid **wqids =
	255	va_arg(ap, struct p9_qid **);
	256
	257	*wqids = NULL;
	258
	259	errcode =
342fee1d	260	p9pdu_readf(pdu, proto_version, "w", nwqid);
ace51c4d EVH	261	if (!errcode) {
	262	*wqids =
	263	kmalloc(nwqid
	264	sizeof(struct p9_qid),
eeff66ef	265	GFP_NOFS);
ace51c4d EVH	266	if (*wqids == NULL)
	267	errcode = -ENOMEM;
	268	}
	269
	270	if (!errcode) {
	271	int i;
	272
	273	for (i = 0; i < *nwqid; i++) {
	274	errcode =
342fee1d SK	275	p9pdu_readf(pdu,
342fee1d SK	276	proto_version,
ace51c4d EVH	277	"Q",
	278	&(*wqids)[i]);
	279	if (errcode)
	280	break;
	281	}
	282	}
	283
	284	if (errcode) {
	285	kfree(*wqids);
	286	*wqids = NULL;
	287	}
	288	}
	289	break;
f0853122 SK	290	case 'A': {
	291	struct p9_stat_dotl *stbuf =
	292	va_arg(ap, struct p9_stat_dotl *);
	293
	294	memset(stbuf, 0, sizeof(struct p9_stat_dotl));
	295	errcode =
	296	p9pdu_readf(pdu, proto_version,
	297	"qQdddqqqqqqqqqqqqqqq",
	298	&stbuf->st_result_mask,
	299	&stbuf->qid,
	300	&stbuf->st_mode,
	301	&stbuf->st_uid, &stbuf->st_gid,
	302	&stbuf->st_nlink,
	303	&stbuf->st_rdev, &stbuf->st_size,
	304	&stbuf->st_blksize, &stbuf->st_blocks,
	305	&stbuf->st_atime_sec,
	306	&stbuf->st_atime_nsec,
	307	&stbuf->st_mtime_sec,
	308	&stbuf->st_mtime_nsec,
	309	&stbuf->st_ctime_sec,
	310	&stbuf->st_ctime_nsec,
	311	&stbuf->st_btime_sec,
	312	&stbuf->st_btime_nsec,
	313	&stbuf->st_gen,
	314	&stbuf->st_data_version);
	315	}
	316	break;
ace51c4d	317	case '?':
c56e4acf SK	318	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	319	(proto_version != p9_proto_2000L))
ace51c4d EVH	320	return 0;
	321	break;
	322	default:
	323	BUG();
	324	break;
	325	}
	326
	327	if (errcode)
	328	break;
	329	}
	330
	331	return errcode;
	332	}
	333
	334	int
342fee1d SK	335	p9pdu_vwritef(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	336	va_list ap)
ace51c4d EVH	337	{
	338	const char *ptr;
	339	int errcode = 0;
	340
	341	for (ptr = fmt; *ptr; ptr++) {
	342	switch (*ptr) {
	343	case 'b':{
	344	int8_t val = va_arg(ap, int);
	345	if (pdu_write(pdu, &val, sizeof(val)))
	346	errcode = -EFAULT;
	347	}
	348	break;
	349	case 'w':{
beeebc92	350	__le16 val = cpu_to_le16(va_arg(ap, int));
ace51c4d EVH	351	if (pdu_write(pdu, &val, sizeof(val)))
	352	errcode = -EFAULT;
	353	}
	354	break;
	355	case 'd':{
beeebc92	356	__le32 val = cpu_to_le32(va_arg(ap, int32_t));
ace51c4d EVH	357	if (pdu_write(pdu, &val, sizeof(val)))
	358	errcode = -EFAULT;
	359	}
	360	break;
	361	case 'q':{
beeebc92	362	__le64 val = cpu_to_le64(va_arg(ap, int64_t));
ace51c4d EVH	363	if (pdu_write(pdu, &val, sizeof(val)))
	364	errcode = -EFAULT;
	365	}
	366	break;
	367	case 's':{
e45c5405	368	const char sptr = va_arg(ap, const char );
219fd58b	369	uint16_t len = 0;
e45c5405	370	if (sptr)
219fd58b MK	371	len = min_t(uint16_t, strlen(sptr),
219fd58b MK	372	USHRT_MAX);
ace51c4d	373
342fee1d SK	374	errcode = p9pdu_writef(pdu, proto_version,
342fee1d SK	375	"w", len);
e45c5405	376	if (!errcode && pdu_write(pdu, sptr, len))
ace51c4d EVH	377	errcode = -EFAULT;
	378	}
	379	break;
	380	case 'Q':{
	381	const struct p9_qid *qid =
	382	va_arg(ap, const struct p9_qid *);
	383	errcode =
342fee1d	384	p9pdu_writef(pdu, proto_version, "bdq",
ace51c4d EVH	385	qid->type, qid->version,
	386	qid->path);
	387	} break;
	388	case 'S':{
	389	const struct p9_wstat *stbuf =
	390	va_arg(ap, const struct p9_wstat *);
	391	errcode =
342fee1d	392	p9pdu_writef(pdu, proto_version,
ace51c4d EVH	393	"wwdQdddqssss?sddd",
ace51c4d EVH	394	stbuf->size, stbuf->type,
51a87c55	395	stbuf->dev, &stbuf->qid,
ace51c4d EVH	396	stbuf->mode, stbuf->atime,
	397	stbuf->mtime, stbuf->length,
	398	stbuf->name, stbuf->uid,
	399	stbuf->gid, stbuf->muid,
	400	stbuf->extension, stbuf->n_uid,
	401	stbuf->n_gid, stbuf->n_muid);
	402	} break;
	403	case 'D':{
219fd58b	404	uint32_t count = va_arg(ap, uint32_t);
ace51c4d EVH	405	const void data = va_arg(ap, const void );
ace51c4d EVH	406
342fee1d SK	407	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	408	count);
ace51c4d EVH	409	if (!errcode && pdu_write(pdu, data, count))
	410	errcode = -EFAULT;
	411	}
	412	break;
51a87c55 EVH	413	case 'U':{
	414	int32_t count = va_arg(ap, int32_t);
	415	const char __user *udata =
e45c5405	416	va_arg(ap, const void __user *);
342fee1d SK	417	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	418	count);
51a87c55 EVH	419	if (!errcode && pdu_write_u(pdu, udata, count))
	420	errcode = -EFAULT;
	421	}
	422	break;
ace51c4d	423	case 'T':{
b76225e2	424	uint16_t nwname = va_arg(ap, int);
ace51c4d EVH	425	const char wnames = va_arg(ap, const char );
ace51c4d EVH	426
342fee1d SK	427	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	428	nwname);
ace51c4d EVH	429	if (!errcode) {
	430	int i;
	431
	432	for (i = 0; i < nwname; i++) {
	433	errcode =
342fee1d SK	434	p9pdu_writef(pdu,
342fee1d SK	435	proto_version,
ace51c4d EVH	436	"s",
	437	wnames[i]);
	438	if (errcode)
	439	break;
	440	}
	441	}
	442	}
	443	break;
	444	case 'R':{
	445	int16_t nwqid = va_arg(ap, int);
	446	struct p9_qid *wqids =
	447	va_arg(ap, struct p9_qid *);
	448
342fee1d SK	449	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	450	nwqid);
ace51c4d EVH	451	if (!errcode) {
	452	int i;
	453
	454	for (i = 0; i < nwqid; i++) {
	455	errcode =
342fee1d SK	456	p9pdu_writef(pdu,
342fee1d SK	457	proto_version,
ace51c4d EVH	458	"Q",
	459	&wqids[i]);
	460	if (errcode)
	461	break;
	462	}
	463	}
	464	}
	465	break;
87d7845a SK	466	case 'I':{
	467	struct p9_iattr_dotl *p9attr = va_arg(ap,
	468	struct p9_iattr_dotl *);
	469
	470	errcode = p9pdu_writef(pdu, proto_version,
	471	"ddddqqqqq",
	472	p9attr->valid,
	473	p9attr->mode,
	474	p9attr->uid,
	475	p9attr->gid,
	476	p9attr->size,
	477	p9attr->atime_sec,
	478	p9attr->atime_nsec,
	479	p9attr->mtime_sec,
	480	p9attr->mtime_nsec);
	481	}
	482	break;
ace51c4d	483	case '?':
c56e4acf SK	484	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	485	(proto_version != p9_proto_2000L))
ace51c4d EVH	486	return 0;
	487	break;
	488	default:
	489	BUG();
	490	break;
	491	}
	492
	493	if (errcode)
	494	break;
	495	}
	496
	497	return errcode;
	498	}
	499
342fee1d	500	int p9pdu_readf(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	501	{
	502	va_list ap;
	503	int ret;
	504
	505	va_start(ap, fmt);
342fee1d	506	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
ace51c4d EVH	507	va_end(ap);
	508
	509	return ret;
	510	}
	511
	512	static int
342fee1d	513	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	514	{
	515	va_list ap;
	516	int ret;
	517
	518	va_start(ap, fmt);
342fee1d	519	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
ace51c4d EVH	520	va_end(ap);
	521
	522	return ret;
	523	}
51a87c55	524
348b5901	525	int p9stat_read(struct p9_client clnt, char buf, int len, struct p9_wstat *st)
02da398b EVH	526	{
02da398b EVH	527	struct p9_fcall fake_pdu;
e7f4b8f1	528	int ret;
02da398b EVH	529
	530	fake_pdu.size = len;
	531	fake_pdu.capacity = len;
	532	fake_pdu.sdata = buf;
	533	fake_pdu.offset = 0;
	534
348b5901	535	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
e7f4b8f1	536	if (ret) {
5d385153	537	p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
348b5901	538	trace_9p_protocol_dump(clnt, &fake_pdu);
e7f4b8f1 EVH	539	}
	540
	541	return ret;
02da398b EVH	542	}
	543	EXPORT_SYMBOL(p9stat_read);
	544
51a87c55 EVH	545	int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
51a87c55 EVH	546	{
9bb6c10a	547	pdu->id = type;
51a87c55 EVH	548	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
	549	}
	550
348b5901	551	int p9pdu_finalize(struct p9_client clnt, struct p9_fcall pdu)
51a87c55 EVH	552	{
	553	int size = pdu->size;
	554	int err;
	555
	556	pdu->size = 0;
	557	err = p9pdu_writef(pdu, 0, "d", size);
	558	pdu->size = size;
	559
348b5901	560	trace_9p_protocol_dump(clnt, pdu);
5d385153 JP	561	p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
5d385153 JP	562	pdu->size, pdu->id, pdu->tag);
e7f4b8f1	563
51a87c55 EVH	564	return err;
	565	}
	566
	567	void p9pdu_reset(struct p9_fcall *pdu)
	568	{
	569	pdu->offset = 0;
	570	pdu->size = 0;
	571	}
7751bdb3	572
348b5901 AK	573	int p9dirent_read(struct p9_client clnt, char buf, int len,
348b5901 AK	574	struct p9_dirent *dirent)
7751bdb3 SK	575	{
	576	struct p9_fcall fake_pdu;
	577	int ret;
	578	char *nameptr;
	579
	580	fake_pdu.size = len;
	581	fake_pdu.capacity = len;
	582	fake_pdu.sdata = buf;
	583	fake_pdu.offset = 0;
	584
348b5901 AK	585	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
348b5901 AK	586	&dirent->d_off, &dirent->d_type, &nameptr);
7751bdb3	587	if (ret) {
5d385153	588	p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
348b5901	589	trace_9p_protocol_dump(clnt, &fake_pdu);
7751bdb3 SK	590	goto out;
	591	}
	592
	593	strcpy(dirent->d_name, nameptr);
1b0bcbcf	594	kfree(nameptr);
7751bdb3 SK	595
	596	out:
	597	return fake_pdu.offset;
	598	}
	599	EXPORT_SYMBOL(p9dirent_read);