[deliverable/linux.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"

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

#ifdef CONFIG_NET_9P_DEBUG
void
p9pdu_dump(int way, struct p9_fcall *pdu)
{
	int len = pdu->size;

	if ((p9_debug_level & P9_DEBUG_VPKT) != P9_DEBUG_VPKT) {
		if ((p9_debug_level & P9_DEBUG_PKT) == P9_DEBUG_PKT) {
			if (len > 32)
				len = 32;
		} else {
			/* shouldn't happen */
			return;
		}
	}

	if (way)
		print_hex_dump_bytes("[9P] ", DUMP_PREFIX_OFFSET, pdu->sdata,
									len);
	else
		print_hex_dump_bytes("]9P[ ", DUMP_PREFIX_OFFSET, pdu->sdata,
									len);
}
#else
void
p9pdu_dump(int way, struct p9_fcall *pdu)
{
}
#endif
EXPORT_SYMBOL(p9pdu_dump);

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(char *buf, int len, struct p9_wstat *st, int proto_version)
{
	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, proto_version, "S", st);
	if (ret) {
		P9_DPRINTK(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
		P9_DUMP_PKT(0, &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_fcall *pdu)
{
	int size = pdu->size;
	int err;

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

	P9_DUMP_PKT(0, pdu);
	P9_DPRINTK(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(char *buf, int len, struct p9_dirent *dirent,
						int proto_version)
{
	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, proto_version, "Qqbs", &dirent->qid,
			&dirent->d_off, &dirent->d_type, &nameptr);
	if (ret) {
		P9_DPRINTK(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
		P9_DUMP_PKT(1, &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
ace51c4d	40	static int
342fee1d	41	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...);
ace51c4d	42
0b15a3a5	43	#ifdef CONFIG_NET_9P_DEBUG
51a87c55 EVH	44	void
	45	p9pdu_dump(int way, struct p9_fcall *pdu)
	46	{
e660a828 EVH	47	int len = pdu->size;
	48
	49	if ((p9_debug_level & P9_DEBUG_VPKT) != P9_DEBUG_VPKT) {
	50	if ((p9_debug_level & P9_DEBUG_PKT) == P9_DEBUG_PKT) {
	51	if (len > 32)
	52	len = 32;
	53	} else {
	54	/* shouldn't happen */
	55	return;
	56	}
51a87c55	57	}
51a87c55 EVH	58
51a87c55 EVH	59	if (way)
e660a828 EVH	60	print_hex_dump_bytes("[9P] ", DUMP_PREFIX_OFFSET, pdu->sdata,
e660a828 EVH	61	len);
51a87c55	62	else
e660a828 EVH	63	print_hex_dump_bytes("]9P[ ", DUMP_PREFIX_OFFSET, pdu->sdata,
e660a828 EVH	64	len);
51a87c55	65	}
0b15a3a5 EVH	66	#else
	67	void
	68	p9pdu_dump(int way, struct p9_fcall *pdu)
	69	{
	70	}
	71	#endif
51a87c55 EVH	72	EXPORT_SYMBOL(p9pdu_dump);
51a87c55 EVH	73
ace51c4d EVH	74	void p9stat_free(struct p9_wstat *stbuf)
	75	{
	76	kfree(stbuf->name);
	77	kfree(stbuf->uid);
	78	kfree(stbuf->gid);
	79	kfree(stbuf->muid);
	80	kfree(stbuf->extension);
	81	}
	82	EXPORT_SYMBOL(p9stat_free);
	83
abfa034e	84	size_t pdu_read(struct p9_fcall pdu, void data, size_t size)
ace51c4d	85	{
01b0c5cf	86	size_t len = min(pdu->size - pdu->offset, size);
ace51c4d EVH	87	memcpy(data, &pdu->sdata[pdu->offset], len);
	88	pdu->offset += len;
	89	return size - len;
	90	}
	91
	92	static size_t pdu_write(struct p9_fcall pdu, const void data, size_t size)
	93	{
01b0c5cf	94	size_t len = min(pdu->capacity - pdu->size, size);
ace51c4d EVH	95	memcpy(&pdu->sdata[pdu->size], data, len);
	96	pdu->size += len;
	97	return size - len;
	98	}
	99
51a87c55 EVH	100	static size_t
	101	pdu_write_u(struct p9_fcall pdu, const char __user udata, size_t size)
	102	{
01b0c5cf	103	size_t len = min(pdu->capacity - pdu->size, size);
7b3bb3fe AK	104	if (copy_from_user(&pdu->sdata[pdu->size], udata, len))
7b3bb3fe AK	105	len = 0;
51a87c55 EVH	106
	107	pdu->size += len;
	108	return size - len;
	109	}
	110
ace51c4d EVH	111	/*
	112	b - int8_t
	113	w - int16_t
	114	d - int32_t
	115	q - int64_t
	116	s - string
	117	S - stat
	118	Q - qid
	119	D - data blob (int32_t size followed by void *, results are not freed)
	120	T - array of strings (int16_t count, followed by strings)
	121	R - array of qids (int16_t count, followed by qids)
f0853122	122	A - stat for 9p2000.L (p9_stat_dotl)
ace51c4d EVH	123	? - if optional = 1, continue parsing
	124	*/
	125
	126	static int
342fee1d SK	127	p9pdu_vreadf(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	128	va_list ap)
ace51c4d EVH	129	{
	130	const char *ptr;
	131	int errcode = 0;
	132
	133	for (ptr = fmt; *ptr; ptr++) {
	134	switch (*ptr) {
	135	case 'b':{
	136	int8_t val = va_arg(ap, int8_t );
	137	if (pdu_read(pdu, val, sizeof(*val))) {
	138	errcode = -EFAULT;
	139	break;
	140	}
	141	}
	142	break;
	143	case 'w':{
	144	int16_t val = va_arg(ap, int16_t );
beeebc92 EVH	145	__le16 le_val;
beeebc92 EVH	146	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	147	errcode = -EFAULT;
	148	break;
	149	}
beeebc92	150	*val = le16_to_cpu(le_val);
ace51c4d EVH	151	}
	152	break;
	153	case 'd':{
	154	int32_t val = va_arg(ap, int32_t );
beeebc92 EVH	155	__le32 le_val;
beeebc92 EVH	156	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	157	errcode = -EFAULT;
	158	break;
	159	}
beeebc92	160	*val = le32_to_cpu(le_val);
ace51c4d EVH	161	}
	162	break;
	163	case 'q':{
	164	int64_t val = va_arg(ap, int64_t );
beeebc92 EVH	165	__le64 le_val;
beeebc92 EVH	166	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	167	errcode = -EFAULT;
	168	break;
	169	}
beeebc92	170	*val = le64_to_cpu(le_val);
ace51c4d EVH	171	}
	172	break;
	173	case 's':{
e45c5405	174	char sptr = va_arg(ap, char );
219fd58b	175	uint16_t len;
ace51c4d	176
342fee1d SK	177	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	178	"w", &len);
ace51c4d EVH	179	if (errcode)
	180	break;
	181
eeff66ef	182	*sptr = kmalloc(len + 1, GFP_NOFS);
e45c5405	183	if (*sptr == NULL) {
ace51c4d EVH	184	errcode = -EFAULT;
	185	break;
	186	}
219fd58b	187	if (pdu_read(pdu, *sptr, len)) {
ace51c4d	188	errcode = -EFAULT;
e45c5405 EVH	189	kfree(*sptr);
e45c5405 EVH	190	*sptr = NULL;
ace51c4d	191	} else
219fd58b	192	(*sptr)[len] = 0;
ace51c4d EVH	193	}
	194	break;
	195	case 'Q':{
	196	struct p9_qid *qid =
	197	va_arg(ap, struct p9_qid *);
	198
342fee1d	199	errcode = p9pdu_readf(pdu, proto_version, "bdq",
ace51c4d EVH	200	&qid->type, &qid->version,
	201	&qid->path);
	202	}
	203	break;
	204	case 'S':{
	205	struct p9_wstat *stbuf =
	206	va_arg(ap, struct p9_wstat *);
	207
f0a0ac2e	208	memset(stbuf, 0, sizeof(struct p9_wstat));
ace51c4d	209	stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
f0a0ac2e	210	-1;
ace51c4d	211	errcode =
342fee1d	212	p9pdu_readf(pdu, proto_version,
ace51c4d EVH	213	"wwdQdddqssss?sddd",
	214	&stbuf->size, &stbuf->type,
	215	&stbuf->dev, &stbuf->qid,
	216	&stbuf->mode, &stbuf->atime,
	217	&stbuf->mtime, &stbuf->length,
	218	&stbuf->name, &stbuf->uid,
	219	&stbuf->gid, &stbuf->muid,
	220	&stbuf->extension,
	221	&stbuf->n_uid, &stbuf->n_gid,
	222	&stbuf->n_muid);
	223	if (errcode)
	224	p9stat_free(stbuf);
	225	}
	226	break;
	227	case 'D':{
219fd58b	228	uint32_t count = va_arg(ap, uint32_t );
ace51c4d EVH	229	void data = va_arg(ap, void );
	230
	231	errcode =
342fee1d	232	p9pdu_readf(pdu, proto_version, "d", count);
ace51c4d EVH	233	if (!errcode) {
ace51c4d EVH	234	*count =
219fd58b	235	min_t(uint32_t, *count,
01b0c5cf	236	pdu->size - pdu->offset);
ace51c4d EVH	237	*data = &pdu->sdata[pdu->offset];
	238	}
	239	}
	240	break;
	241	case 'T':{
b76225e2	242	uint16_t nwname = va_arg(ap, uint16_t );
ace51c4d EVH	243	char *wnames = va_arg(ap, char *);
ace51c4d EVH	244
342fee1d SK	245	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	246	"w", nwname);
ace51c4d EVH	247	if (!errcode) {
	248	*wnames =
	249	kmalloc(sizeof(char ) *nwname,
eeff66ef	250	GFP_NOFS);
ace51c4d EVH	251	if (!*wnames)
	252	errcode = -ENOMEM;
	253	}
	254
	255	if (!errcode) {
	256	int i;
	257
	258	for (i = 0; i < *nwname; i++) {
	259	errcode =
342fee1d SK	260	p9pdu_readf(pdu,
342fee1d SK	261	proto_version,
ace51c4d EVH	262	"s",
	263	&(*wnames)[i]);
	264	if (errcode)
	265	break;
	266	}
	267	}
	268
	269	if (errcode) {
	270	if (*wnames) {
	271	int i;
	272
	273	for (i = 0; i < *nwname; i++)
	274	kfree((*wnames)[i]);
	275	}
	276	kfree(*wnames);
	277	*wnames = NULL;
	278	}
	279	}
	280	break;
	281	case 'R':{
	282	int16_t nwqid = va_arg(ap, int16_t );
	283	struct p9_qid **wqids =
	284	va_arg(ap, struct p9_qid **);
	285
	286	*wqids = NULL;
	287
	288	errcode =
342fee1d	289	p9pdu_readf(pdu, proto_version, "w", nwqid);
ace51c4d EVH	290	if (!errcode) {
	291	*wqids =
	292	kmalloc(nwqid
	293	sizeof(struct p9_qid),
eeff66ef	294	GFP_NOFS);
ace51c4d EVH	295	if (*wqids == NULL)
	296	errcode = -ENOMEM;
	297	}
	298
	299	if (!errcode) {
	300	int i;
	301
	302	for (i = 0; i < *nwqid; i++) {
	303	errcode =
342fee1d SK	304	p9pdu_readf(pdu,
342fee1d SK	305	proto_version,
ace51c4d EVH	306	"Q",
	307	&(*wqids)[i]);
	308	if (errcode)
	309	break;
	310	}
	311	}
	312
	313	if (errcode) {
	314	kfree(*wqids);
	315	*wqids = NULL;
	316	}
	317	}
	318	break;
f0853122 SK	319	case 'A': {
	320	struct p9_stat_dotl *stbuf =
	321	va_arg(ap, struct p9_stat_dotl *);
	322
	323	memset(stbuf, 0, sizeof(struct p9_stat_dotl));
	324	errcode =
	325	p9pdu_readf(pdu, proto_version,
	326	"qQdddqqqqqqqqqqqqqqq",
	327	&stbuf->st_result_mask,
	328	&stbuf->qid,
	329	&stbuf->st_mode,
	330	&stbuf->st_uid, &stbuf->st_gid,
	331	&stbuf->st_nlink,
	332	&stbuf->st_rdev, &stbuf->st_size,
	333	&stbuf->st_blksize, &stbuf->st_blocks,
	334	&stbuf->st_atime_sec,
	335	&stbuf->st_atime_nsec,
	336	&stbuf->st_mtime_sec,
	337	&stbuf->st_mtime_nsec,
	338	&stbuf->st_ctime_sec,
	339	&stbuf->st_ctime_nsec,
	340	&stbuf->st_btime_sec,
	341	&stbuf->st_btime_nsec,
	342	&stbuf->st_gen,
	343	&stbuf->st_data_version);
	344	}
	345	break;
ace51c4d	346	case '?':
c56e4acf SK	347	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	348	(proto_version != p9_proto_2000L))
ace51c4d EVH	349	return 0;
	350	break;
	351	default:
	352	BUG();
	353	break;
	354	}
	355
	356	if (errcode)
	357	break;
	358	}
	359
	360	return errcode;
	361	}
	362
	363	int
342fee1d SK	364	p9pdu_vwritef(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	365	va_list ap)
ace51c4d EVH	366	{
	367	const char *ptr;
	368	int errcode = 0;
	369
	370	for (ptr = fmt; *ptr; ptr++) {
	371	switch (*ptr) {
	372	case 'b':{
	373	int8_t val = va_arg(ap, int);
	374	if (pdu_write(pdu, &val, sizeof(val)))
	375	errcode = -EFAULT;
	376	}
	377	break;
	378	case 'w':{
beeebc92	379	__le16 val = cpu_to_le16(va_arg(ap, int));
ace51c4d EVH	380	if (pdu_write(pdu, &val, sizeof(val)))
	381	errcode = -EFAULT;
	382	}
	383	break;
	384	case 'd':{
beeebc92	385	__le32 val = cpu_to_le32(va_arg(ap, int32_t));
ace51c4d EVH	386	if (pdu_write(pdu, &val, sizeof(val)))
	387	errcode = -EFAULT;
	388	}
	389	break;
	390	case 'q':{
beeebc92	391	__le64 val = cpu_to_le64(va_arg(ap, int64_t));
ace51c4d EVH	392	if (pdu_write(pdu, &val, sizeof(val)))
	393	errcode = -EFAULT;
	394	}
	395	break;
	396	case 's':{
e45c5405	397	const char sptr = va_arg(ap, const char );
219fd58b	398	uint16_t len = 0;
e45c5405	399	if (sptr)
219fd58b MK	400	len = min_t(uint16_t, strlen(sptr),
219fd58b MK	401	USHRT_MAX);
ace51c4d	402
342fee1d SK	403	errcode = p9pdu_writef(pdu, proto_version,
342fee1d SK	404	"w", len);
e45c5405	405	if (!errcode && pdu_write(pdu, sptr, len))
ace51c4d EVH	406	errcode = -EFAULT;
	407	}
	408	break;
	409	case 'Q':{
	410	const struct p9_qid *qid =
	411	va_arg(ap, const struct p9_qid *);
	412	errcode =
342fee1d	413	p9pdu_writef(pdu, proto_version, "bdq",
ace51c4d EVH	414	qid->type, qid->version,
	415	qid->path);
	416	} break;
	417	case 'S':{
	418	const struct p9_wstat *stbuf =
	419	va_arg(ap, const struct p9_wstat *);
	420	errcode =
342fee1d	421	p9pdu_writef(pdu, proto_version,
ace51c4d EVH	422	"wwdQdddqssss?sddd",
ace51c4d EVH	423	stbuf->size, stbuf->type,
51a87c55	424	stbuf->dev, &stbuf->qid,
ace51c4d EVH	425	stbuf->mode, stbuf->atime,
	426	stbuf->mtime, stbuf->length,
	427	stbuf->name, stbuf->uid,
	428	stbuf->gid, stbuf->muid,
	429	stbuf->extension, stbuf->n_uid,
	430	stbuf->n_gid, stbuf->n_muid);
	431	} break;
	432	case 'D':{
219fd58b	433	uint32_t count = va_arg(ap, uint32_t);
ace51c4d EVH	434	const void data = va_arg(ap, const void );
ace51c4d EVH	435
342fee1d SK	436	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	437	count);
ace51c4d EVH	438	if (!errcode && pdu_write(pdu, data, count))
	439	errcode = -EFAULT;
	440	}
	441	break;
51a87c55 EVH	442	case 'U':{
	443	int32_t count = va_arg(ap, int32_t);
	444	const char __user *udata =
e45c5405	445	va_arg(ap, const void __user *);
342fee1d SK	446	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	447	count);
51a87c55 EVH	448	if (!errcode && pdu_write_u(pdu, udata, count))
	449	errcode = -EFAULT;
	450	}
	451	break;
ace51c4d	452	case 'T':{
b76225e2	453	uint16_t nwname = va_arg(ap, int);
ace51c4d EVH	454	const char wnames = va_arg(ap, const char );
ace51c4d EVH	455
342fee1d SK	456	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	457	nwname);
ace51c4d EVH	458	if (!errcode) {
	459	int i;
	460
	461	for (i = 0; i < nwname; i++) {
	462	errcode =
342fee1d SK	463	p9pdu_writef(pdu,
342fee1d SK	464	proto_version,
ace51c4d EVH	465	"s",
	466	wnames[i]);
	467	if (errcode)
	468	break;
	469	}
	470	}
	471	}
	472	break;
	473	case 'R':{
	474	int16_t nwqid = va_arg(ap, int);
	475	struct p9_qid *wqids =
	476	va_arg(ap, struct p9_qid *);
	477
342fee1d SK	478	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	479	nwqid);
ace51c4d EVH	480	if (!errcode) {
	481	int i;
	482
	483	for (i = 0; i < nwqid; i++) {
	484	errcode =
342fee1d SK	485	p9pdu_writef(pdu,
342fee1d SK	486	proto_version,
ace51c4d EVH	487	"Q",
	488	&wqids[i]);
	489	if (errcode)
	490	break;
	491	}
	492	}
	493	}
	494	break;
87d7845a SK	495	case 'I':{
	496	struct p9_iattr_dotl *p9attr = va_arg(ap,
	497	struct p9_iattr_dotl *);
	498
	499	errcode = p9pdu_writef(pdu, proto_version,
	500	"ddddqqqqq",
	501	p9attr->valid,
	502	p9attr->mode,
	503	p9attr->uid,
	504	p9attr->gid,
	505	p9attr->size,
	506	p9attr->atime_sec,
	507	p9attr->atime_nsec,
	508	p9attr->mtime_sec,
	509	p9attr->mtime_nsec);
	510	}
	511	break;
ace51c4d	512	case '?':
c56e4acf SK	513	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	514	(proto_version != p9_proto_2000L))
ace51c4d EVH	515	return 0;
	516	break;
	517	default:
	518	BUG();
	519	break;
	520	}
	521
	522	if (errcode)
	523	break;
	524	}
	525
	526	return errcode;
	527	}
	528
342fee1d	529	int p9pdu_readf(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	530	{
	531	va_list ap;
	532	int ret;
	533
	534	va_start(ap, fmt);
342fee1d	535	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
ace51c4d EVH	536	va_end(ap);
	537
	538	return ret;
	539	}
	540
	541	static int
342fee1d	542	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	543	{
	544	va_list ap;
	545	int ret;
	546
	547	va_start(ap, fmt);
342fee1d	548	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
ace51c4d EVH	549	va_end(ap);
	550
	551	return ret;
	552	}
51a87c55	553
342fee1d	554	int p9stat_read(char buf, int len, struct p9_wstat st, int proto_version)
02da398b EVH	555	{
02da398b EVH	556	struct p9_fcall fake_pdu;
e7f4b8f1	557	int ret;
02da398b EVH	558
	559	fake_pdu.size = len;
	560	fake_pdu.capacity = len;
	561	fake_pdu.sdata = buf;
	562	fake_pdu.offset = 0;
	563
342fee1d	564	ret = p9pdu_readf(&fake_pdu, proto_version, "S", st);
e7f4b8f1 EVH	565	if (ret) {
e7f4b8f1 EVH	566	P9_DPRINTK(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
e660a828	567	P9_DUMP_PKT(0, &fake_pdu);
e7f4b8f1 EVH	568	}
	569
	570	return ret;
02da398b EVH	571	}
	572	EXPORT_SYMBOL(p9stat_read);
	573
51a87c55 EVH	574	int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
51a87c55 EVH	575	{
9bb6c10a	576	pdu->id = type;
51a87c55 EVH	577	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
	578	}
	579
	580	int p9pdu_finalize(struct p9_fcall *pdu)
	581	{
	582	int size = pdu->size;
	583	int err;
	584
	585	pdu->size = 0;
	586	err = p9pdu_writef(pdu, 0, "d", size);
	587	pdu->size = size;
	588
e660a828	589	P9_DUMP_PKT(0, pdu);
e7f4b8f1 EVH	590	P9_DPRINTK(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n", pdu->size,
	591	pdu->id, pdu->tag);
	592
51a87c55 EVH	593	return err;
	594	}
	595
	596	void p9pdu_reset(struct p9_fcall *pdu)
	597	{
	598	pdu->offset = 0;
	599	pdu->size = 0;
	600	}
7751bdb3 SK	601
	602	int p9dirent_read(char buf, int len, struct p9_dirent dirent,
	603	int proto_version)
	604	{
	605	struct p9_fcall fake_pdu;
	606	int ret;
	607	char *nameptr;
	608
	609	fake_pdu.size = len;
	610	fake_pdu.capacity = len;
	611	fake_pdu.sdata = buf;
	612	fake_pdu.offset = 0;
	613
	614	ret = p9pdu_readf(&fake_pdu, proto_version, "Qqbs", &dirent->qid,
	615	&dirent->d_off, &dirent->d_type, &nameptr);
	616	if (ret) {
	617	P9_DPRINTK(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
e660a828	618	P9_DUMP_PKT(1, &fake_pdu);
7751bdb3 SK	619	goto out;
	620	}
	621
	622	strcpy(dirent->d_name, nameptr);
1b0bcbcf	623	kfree(nameptr);
7751bdb3 SK	624
	625	out:
	626	return fake_pdu.offset;
	627	}
	628	EXPORT_SYMBOL(p9dirent_read);