[mirror_ubuntu-artful-kernel.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
	u - numeric uid
	g - numeric gid
	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 'u': {
				kuid_t *uid = va_arg(ap, kuid_t *);
				__le32 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*uid = make_kuid(&init_user_ns,
						 le32_to_cpu(le_val));
			} break;
		case 'g': {
				kgid_t *gid = va_arg(ap, kgid_t *);
				__le32 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*gid = make_kgid(&init_user_ns,
						 le32_to_cpu(le_val));
			} 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_muid = INVALID_UID;
				stbuf->n_gid = INVALID_GID;

				errcode =
				    p9pdu_readf(pdu, proto_version,
						"wwdQdddqssss?sugu",
						&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,
					"qQdugqqqqqqqqqqqqqqq",
					&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(size_t, strlen(sptr),
								USHRT_MAX);

				errcode = p9pdu_writef(pdu, proto_version,
								"w", len);
				if (!errcode && pdu_write(pdu, sptr, len))
					errcode = -EFAULT;
			}
			break;
		case 'u': {
				kuid_t uid = va_arg(ap, kuid_t);
				__le32 val = cpu_to_le32(
						from_kuid(&init_user_ns, uid));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			} break;
		case 'g': {
				kgid_t gid = va_arg(ap, kgid_t);
				__le32 val = cpu_to_le32(
						from_kgid(&init_user_ns, gid));
				if (pdu_write(pdu, &val, sizeof(val)))
					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?sugu",
						 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,
							"ddugqqqqq",
							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
97fc8b1e EB	88	u - numeric uid
97fc8b1e EB	89	g - numeric gid
ace51c4d EVH	90	S - stat
	91	Q - qid
	92	D - data blob (int32_t size followed by void *, results are not freed)
	93	T - array of strings (int16_t count, followed by strings)
	94	R - array of qids (int16_t count, followed by qids)
f0853122	95	A - stat for 9p2000.L (p9_stat_dotl)
ace51c4d EVH	96	? - if optional = 1, continue parsing
	97	*/
	98
	99	static int
342fee1d SK	100	p9pdu_vreadf(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	101	va_list ap)
ace51c4d EVH	102	{
	103	const char *ptr;
	104	int errcode = 0;
	105
	106	for (ptr = fmt; *ptr; ptr++) {
	107	switch (*ptr) {
	108	case 'b':{
	109	int8_t val = va_arg(ap, int8_t );
	110	if (pdu_read(pdu, val, sizeof(*val))) {
	111	errcode = -EFAULT;
	112	break;
	113	}
	114	}
	115	break;
	116	case 'w':{
	117	int16_t val = va_arg(ap, int16_t );
beeebc92 EVH	118	__le16 le_val;
beeebc92 EVH	119	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	120	errcode = -EFAULT;
	121	break;
	122	}
beeebc92	123	*val = le16_to_cpu(le_val);
ace51c4d EVH	124	}
	125	break;
	126	case 'd':{
	127	int32_t val = va_arg(ap, int32_t );
beeebc92 EVH	128	__le32 le_val;
beeebc92 EVH	129	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	130	errcode = -EFAULT;
	131	break;
	132	}
beeebc92	133	*val = le32_to_cpu(le_val);
ace51c4d EVH	134	}
	135	break;
	136	case 'q':{
	137	int64_t val = va_arg(ap, int64_t );
beeebc92 EVH	138	__le64 le_val;
beeebc92 EVH	139	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	140	errcode = -EFAULT;
	141	break;
	142	}
beeebc92	143	*val = le64_to_cpu(le_val);
ace51c4d EVH	144	}
	145	break;
	146	case 's':{
e45c5405	147	char sptr = va_arg(ap, char );
219fd58b	148	uint16_t len;
ace51c4d	149
342fee1d SK	150	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	151	"w", &len);
ace51c4d EVH	152	if (errcode)
	153	break;
	154
eeff66ef	155	*sptr = kmalloc(len + 1, GFP_NOFS);
e45c5405	156	if (*sptr == NULL) {
ace51c4d EVH	157	errcode = -EFAULT;
	158	break;
	159	}
219fd58b	160	if (pdu_read(pdu, *sptr, len)) {
ace51c4d	161	errcode = -EFAULT;
e45c5405 EVH	162	kfree(*sptr);
e45c5405 EVH	163	*sptr = NULL;
ace51c4d	164	} else
219fd58b	165	(*sptr)[len] = 0;
ace51c4d EVH	166	}
ace51c4d EVH	167	break;
97fc8b1e EB	168	case 'u': {
	169	kuid_t uid = va_arg(ap, kuid_t );
	170	__le32 le_val;
	171	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
	172	errcode = -EFAULT;
	173	break;
	174	}
	175	*uid = make_kuid(&init_user_ns,
	176	le32_to_cpu(le_val));
	177	} break;
	178	case 'g': {
	179	kgid_t gid = va_arg(ap, kgid_t );
	180	__le32 le_val;
	181	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
	182	errcode = -EFAULT;
	183	break;
	184	}
	185	*gid = make_kgid(&init_user_ns,
	186	le32_to_cpu(le_val));
	187	} break;
ace51c4d EVH	188	case 'Q':{
	189	struct p9_qid *qid =
	190	va_arg(ap, struct p9_qid *);
	191
342fee1d	192	errcode = p9pdu_readf(pdu, proto_version, "bdq",
ace51c4d EVH	193	&qid->type, &qid->version,
	194	&qid->path);
	195	}
	196	break;
	197	case 'S':{
	198	struct p9_wstat *stbuf =
	199	va_arg(ap, struct p9_wstat *);
	200
f0a0ac2e	201	memset(stbuf, 0, sizeof(struct p9_wstat));
447c5094 EB	202	stbuf->n_uid = stbuf->n_muid = INVALID_UID;
	203	stbuf->n_gid = INVALID_GID;
	204
ace51c4d	205	errcode =
342fee1d	206	p9pdu_readf(pdu, proto_version,
447c5094	207	"wwdQdddqssss?sugu",
ace51c4d EVH	208	&stbuf->size, &stbuf->type,
	209	&stbuf->dev, &stbuf->qid,
	210	&stbuf->mode, &stbuf->atime,
	211	&stbuf->mtime, &stbuf->length,
	212	&stbuf->name, &stbuf->uid,
	213	&stbuf->gid, &stbuf->muid,
	214	&stbuf->extension,
	215	&stbuf->n_uid, &stbuf->n_gid,
	216	&stbuf->n_muid);
	217	if (errcode)
	218	p9stat_free(stbuf);
	219	}
	220	break;
	221	case 'D':{
219fd58b	222	uint32_t count = va_arg(ap, uint32_t );
ace51c4d EVH	223	void data = va_arg(ap, void );
	224
	225	errcode =
342fee1d	226	p9pdu_readf(pdu, proto_version, "d", count);
ace51c4d EVH	227	if (!errcode) {
ace51c4d EVH	228	*count =
219fd58b	229	min_t(uint32_t, *count,
01b0c5cf	230	pdu->size - pdu->offset);
ace51c4d EVH	231	*data = &pdu->sdata[pdu->offset];
	232	}
	233	}
	234	break;
	235	case 'T':{
b76225e2	236	uint16_t nwname = va_arg(ap, uint16_t );
ace51c4d EVH	237	char *wnames = va_arg(ap, char *);
ace51c4d EVH	238
342fee1d SK	239	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	240	"w", nwname);
ace51c4d EVH	241	if (!errcode) {
	242	*wnames =
	243	kmalloc(sizeof(char ) *nwname,
eeff66ef	244	GFP_NOFS);
ace51c4d EVH	245	if (!*wnames)
	246	errcode = -ENOMEM;
	247	}
	248
	249	if (!errcode) {
	250	int i;
	251
	252	for (i = 0; i < *nwname; i++) {
	253	errcode =
342fee1d SK	254	p9pdu_readf(pdu,
342fee1d SK	255	proto_version,
ace51c4d EVH	256	"s",
	257	&(*wnames)[i]);
	258	if (errcode)
	259	break;
	260	}
	261	}
	262
	263	if (errcode) {
	264	if (*wnames) {
	265	int i;
	266
	267	for (i = 0; i < *nwname; i++)
	268	kfree((*wnames)[i]);
	269	}
	270	kfree(*wnames);
	271	*wnames = NULL;
	272	}
	273	}
	274	break;
	275	case 'R':{
	276	int16_t nwqid = va_arg(ap, int16_t );
	277	struct p9_qid **wqids =
	278	va_arg(ap, struct p9_qid **);
	279
	280	*wqids = NULL;
	281
	282	errcode =
342fee1d	283	p9pdu_readf(pdu, proto_version, "w", nwqid);
ace51c4d EVH	284	if (!errcode) {
	285	*wqids =
	286	kmalloc(nwqid
	287	sizeof(struct p9_qid),
eeff66ef	288	GFP_NOFS);
ace51c4d EVH	289	if (*wqids == NULL)
	290	errcode = -ENOMEM;
	291	}
	292
	293	if (!errcode) {
	294	int i;
	295
	296	for (i = 0; i < *nwqid; i++) {
	297	errcode =
342fee1d SK	298	p9pdu_readf(pdu,
342fee1d SK	299	proto_version,
ace51c4d EVH	300	"Q",
	301	&(*wqids)[i]);
	302	if (errcode)
	303	break;
	304	}
	305	}
	306
	307	if (errcode) {
	308	kfree(*wqids);
	309	*wqids = NULL;
	310	}
	311	}
	312	break;
f0853122 SK	313	case 'A': {
	314	struct p9_stat_dotl *stbuf =
	315	va_arg(ap, struct p9_stat_dotl *);
	316
	317	memset(stbuf, 0, sizeof(struct p9_stat_dotl));
	318	errcode =
	319	p9pdu_readf(pdu, proto_version,
447c5094	320	"qQdugqqqqqqqqqqqqqqq",
f0853122 SK	321	&stbuf->st_result_mask,
	322	&stbuf->qid,
	323	&stbuf->st_mode,
	324	&stbuf->st_uid, &stbuf->st_gid,
	325	&stbuf->st_nlink,
	326	&stbuf->st_rdev, &stbuf->st_size,
	327	&stbuf->st_blksize, &stbuf->st_blocks,
	328	&stbuf->st_atime_sec,
	329	&stbuf->st_atime_nsec,
	330	&stbuf->st_mtime_sec,
	331	&stbuf->st_mtime_nsec,
	332	&stbuf->st_ctime_sec,
	333	&stbuf->st_ctime_nsec,
	334	&stbuf->st_btime_sec,
	335	&stbuf->st_btime_nsec,
	336	&stbuf->st_gen,
	337	&stbuf->st_data_version);
	338	}
	339	break;
ace51c4d	340	case '?':
c56e4acf SK	341	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	342	(proto_version != p9_proto_2000L))
ace51c4d EVH	343	return 0;
	344	break;
	345	default:
	346	BUG();
	347	break;
	348	}
	349
	350	if (errcode)
	351	break;
	352	}
	353
	354	return errcode;
	355	}
	356
	357	int
342fee1d SK	358	p9pdu_vwritef(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	359	va_list ap)
ace51c4d EVH	360	{
	361	const char *ptr;
	362	int errcode = 0;
	363
	364	for (ptr = fmt; *ptr; ptr++) {
	365	switch (*ptr) {
	366	case 'b':{
	367	int8_t val = va_arg(ap, int);
	368	if (pdu_write(pdu, &val, sizeof(val)))
	369	errcode = -EFAULT;
	370	}
	371	break;
	372	case 'w':{
beeebc92	373	__le16 val = cpu_to_le16(va_arg(ap, int));
ace51c4d EVH	374	if (pdu_write(pdu, &val, sizeof(val)))
	375	errcode = -EFAULT;
	376	}
	377	break;
	378	case 'd':{
beeebc92	379	__le32 val = cpu_to_le32(va_arg(ap, int32_t));
ace51c4d EVH	380	if (pdu_write(pdu, &val, sizeof(val)))
	381	errcode = -EFAULT;
	382	}
	383	break;
	384	case 'q':{
beeebc92	385	__le64 val = cpu_to_le64(va_arg(ap, int64_t));
ace51c4d EVH	386	if (pdu_write(pdu, &val, sizeof(val)))
	387	errcode = -EFAULT;
	388	}
	389	break;
	390	case 's':{
e45c5405	391	const char sptr = va_arg(ap, const char );
219fd58b	392	uint16_t len = 0;
e45c5405	393	if (sptr)
d31bb4f0	394	len = min_t(size_t, strlen(sptr),
219fd58b	395	USHRT_MAX);
ace51c4d	396
342fee1d SK	397	errcode = p9pdu_writef(pdu, proto_version,
342fee1d SK	398	"w", len);
e45c5405	399	if (!errcode && pdu_write(pdu, sptr, len))
ace51c4d EVH	400	errcode = -EFAULT;
	401	}
	402	break;
97fc8b1e EB	403	case 'u': {
	404	kuid_t uid = va_arg(ap, kuid_t);
	405	__le32 val = cpu_to_le32(
	406	from_kuid(&init_user_ns, uid));
	407	if (pdu_write(pdu, &val, sizeof(val)))
	408	errcode = -EFAULT;
	409	} break;
	410	case 'g': {
	411	kgid_t gid = va_arg(ap, kgid_t);
	412	__le32 val = cpu_to_le32(
	413	from_kgid(&init_user_ns, gid));
	414	if (pdu_write(pdu, &val, sizeof(val)))
	415	errcode = -EFAULT;
	416	} break;
ace51c4d EVH	417	case 'Q':{
	418	const struct p9_qid *qid =
	419	va_arg(ap, const struct p9_qid *);
	420	errcode =
342fee1d	421	p9pdu_writef(pdu, proto_version, "bdq",
ace51c4d EVH	422	qid->type, qid->version,
	423	qid->path);
	424	} break;
	425	case 'S':{
	426	const struct p9_wstat *stbuf =
	427	va_arg(ap, const struct p9_wstat *);
	428	errcode =
342fee1d	429	p9pdu_writef(pdu, proto_version,
447c5094	430	"wwdQdddqssss?sugu",
ace51c4d	431	stbuf->size, stbuf->type,
51a87c55	432	stbuf->dev, &stbuf->qid,
ace51c4d EVH	433	stbuf->mode, stbuf->atime,
	434	stbuf->mtime, stbuf->length,
	435	stbuf->name, stbuf->uid,
	436	stbuf->gid, stbuf->muid,
	437	stbuf->extension, stbuf->n_uid,
	438	stbuf->n_gid, stbuf->n_muid);
	439	} break;
	440	case 'D':{
219fd58b	441	uint32_t count = va_arg(ap, uint32_t);
ace51c4d EVH	442	const void data = va_arg(ap, const void );
ace51c4d EVH	443
342fee1d SK	444	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	445	count);
ace51c4d EVH	446	if (!errcode && pdu_write(pdu, data, count))
	447	errcode = -EFAULT;
	448	}
	449	break;
51a87c55 EVH	450	case 'U':{
	451	int32_t count = va_arg(ap, int32_t);
	452	const char __user *udata =
e45c5405	453	va_arg(ap, const void __user *);
342fee1d SK	454	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	455	count);
51a87c55 EVH	456	if (!errcode && pdu_write_u(pdu, udata, count))
	457	errcode = -EFAULT;
	458	}
	459	break;
ace51c4d	460	case 'T':{
b76225e2	461	uint16_t nwname = va_arg(ap, int);
ace51c4d EVH	462	const char wnames = va_arg(ap, const char );
ace51c4d EVH	463
342fee1d SK	464	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	465	nwname);
ace51c4d EVH	466	if (!errcode) {
	467	int i;
	468
	469	for (i = 0; i < nwname; i++) {
	470	errcode =
342fee1d SK	471	p9pdu_writef(pdu,
342fee1d SK	472	proto_version,
ace51c4d EVH	473	"s",
	474	wnames[i]);
	475	if (errcode)
	476	break;
	477	}
	478	}
	479	}
	480	break;
	481	case 'R':{
	482	int16_t nwqid = va_arg(ap, int);
	483	struct p9_qid *wqids =
	484	va_arg(ap, struct p9_qid *);
	485
342fee1d SK	486	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	487	nwqid);
ace51c4d EVH	488	if (!errcode) {
	489	int i;
	490
	491	for (i = 0; i < nwqid; i++) {
	492	errcode =
342fee1d SK	493	p9pdu_writef(pdu,
342fee1d SK	494	proto_version,
ace51c4d EVH	495	"Q",
	496	&wqids[i]);
	497	if (errcode)
	498	break;
	499	}
	500	}
	501	}
	502	break;
87d7845a SK	503	case 'I':{
	504	struct p9_iattr_dotl *p9attr = va_arg(ap,
	505	struct p9_iattr_dotl *);
	506
	507	errcode = p9pdu_writef(pdu, proto_version,
447c5094	508	"ddugqqqqq",
87d7845a SK	509	p9attr->valid,
	510	p9attr->mode,
	511	p9attr->uid,
	512	p9attr->gid,
	513	p9attr->size,
	514	p9attr->atime_sec,
	515	p9attr->atime_nsec,
	516	p9attr->mtime_sec,
	517	p9attr->mtime_nsec);
	518	}
	519	break;
ace51c4d	520	case '?':
c56e4acf SK	521	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	522	(proto_version != p9_proto_2000L))
ace51c4d EVH	523	return 0;
	524	break;
	525	default:
	526	BUG();
	527	break;
	528	}
	529
	530	if (errcode)
	531	break;
	532	}
	533
	534	return errcode;
	535	}
	536
342fee1d	537	int p9pdu_readf(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	538	{
	539	va_list ap;
	540	int ret;
	541
	542	va_start(ap, fmt);
342fee1d	543	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
ace51c4d EVH	544	va_end(ap);
	545
	546	return ret;
	547	}
	548
	549	static int
342fee1d	550	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	551	{
	552	va_list ap;
	553	int ret;
	554
	555	va_start(ap, fmt);
342fee1d	556	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
ace51c4d EVH	557	va_end(ap);
	558
	559	return ret;
	560	}
51a87c55	561
348b5901	562	int p9stat_read(struct p9_client clnt, char buf, int len, struct p9_wstat *st)
02da398b EVH	563	{
02da398b EVH	564	struct p9_fcall fake_pdu;
e7f4b8f1	565	int ret;
02da398b EVH	566
	567	fake_pdu.size = len;
	568	fake_pdu.capacity = len;
	569	fake_pdu.sdata = buf;
	570	fake_pdu.offset = 0;
	571
348b5901	572	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
e7f4b8f1	573	if (ret) {
5d385153	574	p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
348b5901	575	trace_9p_protocol_dump(clnt, &fake_pdu);
e7f4b8f1 EVH	576	}
	577
	578	return ret;
02da398b EVH	579	}
	580	EXPORT_SYMBOL(p9stat_read);
	581
51a87c55 EVH	582	int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
51a87c55 EVH	583	{
9bb6c10a	584	pdu->id = type;
51a87c55 EVH	585	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
	586	}
	587
348b5901	588	int p9pdu_finalize(struct p9_client clnt, struct p9_fcall pdu)
51a87c55 EVH	589	{
	590	int size = pdu->size;
	591	int err;
	592
	593	pdu->size = 0;
	594	err = p9pdu_writef(pdu, 0, "d", size);
	595	pdu->size = size;
	596
348b5901	597	trace_9p_protocol_dump(clnt, pdu);
5d385153 JP	598	p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
5d385153 JP	599	pdu->size, pdu->id, pdu->tag);
e7f4b8f1	600
51a87c55 EVH	601	return err;
	602	}
	603
	604	void p9pdu_reset(struct p9_fcall *pdu)
	605	{
	606	pdu->offset = 0;
	607	pdu->size = 0;
	608	}
7751bdb3	609
348b5901 AK	610	int p9dirent_read(struct p9_client clnt, char buf, int len,
348b5901 AK	611	struct p9_dirent *dirent)
7751bdb3 SK	612	{
	613	struct p9_fcall fake_pdu;
	614	int ret;
	615	char *nameptr;
	616
	617	fake_pdu.size = len;
	618	fake_pdu.capacity = len;
	619	fake_pdu.sdata = buf;
	620	fake_pdu.offset = 0;
	621
348b5901 AK	622	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
348b5901 AK	623	&dirent->d_off, &dirent->d_type, &nameptr);
7751bdb3	624	if (ret) {
5d385153	625	p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
348b5901	626	trace_9p_protocol_dump(clnt, &fake_pdu);
7751bdb3 SK	627	goto out;
	628	}
	629
	630	strcpy(dirent->d_name, nameptr);
1b0bcbcf	631	kfree(nameptr);
7751bdb3 SK	632
	633	out:
	634	return fake_pdu.offset;
	635	}
	636	EXPORT_SYMBOL(p9dirent_read);