[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);

static 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;
}

static size_t
pdu_write_urw(struct p9_fcall *pdu, const char *kdata, const char __user *udata,
		size_t size)
{
	BUG_ON(pdu->size > P9_IOHDRSZ);
	pdu->pubuf = (char __user *)udata;
	pdu->pkbuf = (char *)kdata;
	pdu->pbuf_size = size;
	return 0;
}

static size_t
pdu_write_readdir(struct p9_fcall *pdu, const char *kdata, size_t size)
{
	BUG_ON(pdu->size > P9_READDIRHDRSZ);
	pdu->pkbuf = (char *)kdata;
	pdu->pbuf_size = size;
	return 0;
}

/*
	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 'E':{
				 int32_t cnt = va_arg(ap, int32_t);
				 const char *k = va_arg(ap, const void *);
				 const char __user *u = va_arg(ap,
							const void __user *);
				 errcode = p9pdu_writef(pdu, proto_version, "d",
						 cnt);
				 if (!errcode && pdu_write_urw(pdu, k, u, cnt))
					errcode = -EFAULT;
			 }
			 break;
		case 'F':{
				 int32_t cnt = va_arg(ap, int32_t);
				 const char *k = va_arg(ap, const void *);
				 errcode = p9pdu_writef(pdu, proto_version, "d",
						 cnt);
				 if (!errcode && pdu_write_readdir(pdu, k, cnt))
					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;
	pdu->private = NULL;
	pdu->pubuf = NULL;
	pdu->pkbuf = NULL;
	pdu->pbuf_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
	84	static size_t pdu_read(struct p9_fcall pdu, void data, size_t size)
	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
bb2f8a55 VJJ	111	static size_t
	112	pdu_write_urw(struct p9_fcall pdu, const char kdata, const char __user *udata,
	113	size_t size)
	114	{
	115	BUG_ON(pdu->size > P9_IOHDRSZ);
	116	pdu->pubuf = (char __user *)udata;
	117	pdu->pkbuf = (char *)kdata;
	118	pdu->pbuf_size = size;
	119	return 0;
	120	}
	121
2c66523f VJJ	122	static size_t
	123	pdu_write_readdir(struct p9_fcall pdu, const char kdata, size_t size)
	124	{
	125	BUG_ON(pdu->size > P9_READDIRHDRSZ);
	126	pdu->pkbuf = (char *)kdata;
	127	pdu->pbuf_size = size;
	128	return 0;
	129	}
	130
ace51c4d EVH	131	/*
	132	b - int8_t
	133	w - int16_t
	134	d - int32_t
	135	q - int64_t
	136	s - string
	137	S - stat
	138	Q - qid
	139	D - data blob (int32_t size followed by void *, results are not freed)
	140	T - array of strings (int16_t count, followed by strings)
	141	R - array of qids (int16_t count, followed by qids)
f0853122	142	A - stat for 9p2000.L (p9_stat_dotl)
ace51c4d EVH	143	? - if optional = 1, continue parsing
	144	*/
	145
	146	static int
342fee1d SK	147	p9pdu_vreadf(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	148	va_list ap)
ace51c4d EVH	149	{
	150	const char *ptr;
	151	int errcode = 0;
	152
	153	for (ptr = fmt; *ptr; ptr++) {
	154	switch (*ptr) {
	155	case 'b':{
	156	int8_t val = va_arg(ap, int8_t );
	157	if (pdu_read(pdu, val, sizeof(*val))) {
	158	errcode = -EFAULT;
	159	break;
	160	}
	161	}
	162	break;
	163	case 'w':{
	164	int16_t val = va_arg(ap, int16_t );
beeebc92 EVH	165	__le16 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 = le16_to_cpu(le_val);
ace51c4d EVH	171	}
	172	break;
	173	case 'd':{
	174	int32_t val = va_arg(ap, int32_t );
beeebc92 EVH	175	__le32 le_val;
beeebc92 EVH	176	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	177	errcode = -EFAULT;
	178	break;
	179	}
beeebc92	180	*val = le32_to_cpu(le_val);
ace51c4d EVH	181	}
	182	break;
	183	case 'q':{
	184	int64_t val = va_arg(ap, int64_t );
beeebc92 EVH	185	__le64 le_val;
beeebc92 EVH	186	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	187	errcode = -EFAULT;
	188	break;
	189	}
beeebc92	190	*val = le64_to_cpu(le_val);
ace51c4d EVH	191	}
	192	break;
	193	case 's':{
e45c5405	194	char sptr = va_arg(ap, char );
219fd58b	195	uint16_t len;
ace51c4d	196
342fee1d SK	197	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	198	"w", &len);
ace51c4d EVH	199	if (errcode)
	200	break;
	201
eeff66ef	202	*sptr = kmalloc(len + 1, GFP_NOFS);
e45c5405	203	if (*sptr == NULL) {
ace51c4d EVH	204	errcode = -EFAULT;
	205	break;
	206	}
219fd58b	207	if (pdu_read(pdu, *sptr, len)) {
ace51c4d	208	errcode = -EFAULT;
e45c5405 EVH	209	kfree(*sptr);
e45c5405 EVH	210	*sptr = NULL;
ace51c4d	211	} else
219fd58b	212	(*sptr)[len] = 0;
ace51c4d EVH	213	}
	214	break;
	215	case 'Q':{
	216	struct p9_qid *qid =
	217	va_arg(ap, struct p9_qid *);
	218
342fee1d	219	errcode = p9pdu_readf(pdu, proto_version, "bdq",
ace51c4d EVH	220	&qid->type, &qid->version,
	221	&qid->path);
	222	}
	223	break;
	224	case 'S':{
	225	struct p9_wstat *stbuf =
	226	va_arg(ap, struct p9_wstat *);
	227
f0a0ac2e	228	memset(stbuf, 0, sizeof(struct p9_wstat));
ace51c4d	229	stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
f0a0ac2e	230	-1;
ace51c4d	231	errcode =
342fee1d	232	p9pdu_readf(pdu, proto_version,
ace51c4d EVH	233	"wwdQdddqssss?sddd",
	234	&stbuf->size, &stbuf->type,
	235	&stbuf->dev, &stbuf->qid,
	236	&stbuf->mode, &stbuf->atime,
	237	&stbuf->mtime, &stbuf->length,
	238	&stbuf->name, &stbuf->uid,
	239	&stbuf->gid, &stbuf->muid,
	240	&stbuf->extension,
	241	&stbuf->n_uid, &stbuf->n_gid,
	242	&stbuf->n_muid);
	243	if (errcode)
	244	p9stat_free(stbuf);
	245	}
	246	break;
	247	case 'D':{
219fd58b	248	uint32_t count = va_arg(ap, uint32_t );
ace51c4d EVH	249	void data = va_arg(ap, void );
	250
	251	errcode =
342fee1d	252	p9pdu_readf(pdu, proto_version, "d", count);
ace51c4d EVH	253	if (!errcode) {
ace51c4d EVH	254	*count =
219fd58b	255	min_t(uint32_t, *count,
01b0c5cf	256	pdu->size - pdu->offset);
ace51c4d EVH	257	*data = &pdu->sdata[pdu->offset];
	258	}
	259	}
	260	break;
	261	case 'T':{
b76225e2	262	uint16_t nwname = va_arg(ap, uint16_t );
ace51c4d EVH	263	char *wnames = va_arg(ap, char *);
ace51c4d EVH	264
342fee1d SK	265	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	266	"w", nwname);
ace51c4d EVH	267	if (!errcode) {
	268	*wnames =
	269	kmalloc(sizeof(char ) *nwname,
eeff66ef	270	GFP_NOFS);
ace51c4d EVH	271	if (!*wnames)
	272	errcode = -ENOMEM;
	273	}
	274
	275	if (!errcode) {
	276	int i;
	277
	278	for (i = 0; i < *nwname; i++) {
	279	errcode =
342fee1d SK	280	p9pdu_readf(pdu,
342fee1d SK	281	proto_version,
ace51c4d EVH	282	"s",
	283	&(*wnames)[i]);
	284	if (errcode)
	285	break;
	286	}
	287	}
	288
	289	if (errcode) {
	290	if (*wnames) {
	291	int i;
	292
	293	for (i = 0; i < *nwname; i++)
	294	kfree((*wnames)[i]);
	295	}
	296	kfree(*wnames);
	297	*wnames = NULL;
	298	}
	299	}
	300	break;
	301	case 'R':{
	302	int16_t nwqid = va_arg(ap, int16_t );
	303	struct p9_qid **wqids =
	304	va_arg(ap, struct p9_qid **);
	305
	306	*wqids = NULL;
	307
	308	errcode =
342fee1d	309	p9pdu_readf(pdu, proto_version, "w", nwqid);
ace51c4d EVH	310	if (!errcode) {
	311	*wqids =
	312	kmalloc(nwqid
	313	sizeof(struct p9_qid),
eeff66ef	314	GFP_NOFS);
ace51c4d EVH	315	if (*wqids == NULL)
	316	errcode = -ENOMEM;
	317	}
	318
	319	if (!errcode) {
	320	int i;
	321
	322	for (i = 0; i < *nwqid; i++) {
	323	errcode =
342fee1d SK	324	p9pdu_readf(pdu,
342fee1d SK	325	proto_version,
ace51c4d EVH	326	"Q",
	327	&(*wqids)[i]);
	328	if (errcode)
	329	break;
	330	}
	331	}
	332
	333	if (errcode) {
	334	kfree(*wqids);
	335	*wqids = NULL;
	336	}
	337	}
	338	break;
f0853122 SK	339	case 'A': {
	340	struct p9_stat_dotl *stbuf =
	341	va_arg(ap, struct p9_stat_dotl *);
	342
	343	memset(stbuf, 0, sizeof(struct p9_stat_dotl));
	344	errcode =
	345	p9pdu_readf(pdu, proto_version,
	346	"qQdddqqqqqqqqqqqqqqq",
	347	&stbuf->st_result_mask,
	348	&stbuf->qid,
	349	&stbuf->st_mode,
	350	&stbuf->st_uid, &stbuf->st_gid,
	351	&stbuf->st_nlink,
	352	&stbuf->st_rdev, &stbuf->st_size,
	353	&stbuf->st_blksize, &stbuf->st_blocks,
	354	&stbuf->st_atime_sec,
	355	&stbuf->st_atime_nsec,
	356	&stbuf->st_mtime_sec,
	357	&stbuf->st_mtime_nsec,
	358	&stbuf->st_ctime_sec,
	359	&stbuf->st_ctime_nsec,
	360	&stbuf->st_btime_sec,
	361	&stbuf->st_btime_nsec,
	362	&stbuf->st_gen,
	363	&stbuf->st_data_version);
	364	}
	365	break;
ace51c4d	366	case '?':
c56e4acf SK	367	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	368	(proto_version != p9_proto_2000L))
ace51c4d EVH	369	return 0;
	370	break;
	371	default:
	372	BUG();
	373	break;
	374	}
	375
	376	if (errcode)
	377	break;
	378	}
	379
	380	return errcode;
	381	}
	382
	383	int
342fee1d SK	384	p9pdu_vwritef(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	385	va_list ap)
ace51c4d EVH	386	{
	387	const char *ptr;
	388	int errcode = 0;
	389
	390	for (ptr = fmt; *ptr; ptr++) {
	391	switch (*ptr) {
	392	case 'b':{
	393	int8_t val = va_arg(ap, int);
	394	if (pdu_write(pdu, &val, sizeof(val)))
	395	errcode = -EFAULT;
	396	}
	397	break;
	398	case 'w':{
beeebc92	399	__le16 val = cpu_to_le16(va_arg(ap, int));
ace51c4d EVH	400	if (pdu_write(pdu, &val, sizeof(val)))
	401	errcode = -EFAULT;
	402	}
	403	break;
	404	case 'd':{
beeebc92	405	__le32 val = cpu_to_le32(va_arg(ap, int32_t));
ace51c4d EVH	406	if (pdu_write(pdu, &val, sizeof(val)))
	407	errcode = -EFAULT;
	408	}
	409	break;
	410	case 'q':{
beeebc92	411	__le64 val = cpu_to_le64(va_arg(ap, int64_t));
ace51c4d EVH	412	if (pdu_write(pdu, &val, sizeof(val)))
	413	errcode = -EFAULT;
	414	}
	415	break;
	416	case 's':{
e45c5405	417	const char sptr = va_arg(ap, const char );
219fd58b	418	uint16_t len = 0;
e45c5405	419	if (sptr)
219fd58b MK	420	len = min_t(uint16_t, strlen(sptr),
219fd58b MK	421	USHRT_MAX);
ace51c4d	422
342fee1d SK	423	errcode = p9pdu_writef(pdu, proto_version,
342fee1d SK	424	"w", len);
e45c5405	425	if (!errcode && pdu_write(pdu, sptr, len))
ace51c4d EVH	426	errcode = -EFAULT;
	427	}
	428	break;
	429	case 'Q':{
	430	const struct p9_qid *qid =
	431	va_arg(ap, const struct p9_qid *);
	432	errcode =
342fee1d	433	p9pdu_writef(pdu, proto_version, "bdq",
ace51c4d EVH	434	qid->type, qid->version,
	435	qid->path);
	436	} break;
	437	case 'S':{
	438	const struct p9_wstat *stbuf =
	439	va_arg(ap, const struct p9_wstat *);
	440	errcode =
342fee1d	441	p9pdu_writef(pdu, proto_version,
ace51c4d EVH	442	"wwdQdddqssss?sddd",
ace51c4d EVH	443	stbuf->size, stbuf->type,
51a87c55	444	stbuf->dev, &stbuf->qid,
ace51c4d EVH	445	stbuf->mode, stbuf->atime,
	446	stbuf->mtime, stbuf->length,
	447	stbuf->name, stbuf->uid,
	448	stbuf->gid, stbuf->muid,
	449	stbuf->extension, stbuf->n_uid,
	450	stbuf->n_gid, stbuf->n_muid);
	451	} break;
	452	case 'D':{
219fd58b	453	uint32_t count = va_arg(ap, uint32_t);
ace51c4d EVH	454	const void data = va_arg(ap, const void );
ace51c4d EVH	455
342fee1d SK	456	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	457	count);
ace51c4d EVH	458	if (!errcode && pdu_write(pdu, data, count))
	459	errcode = -EFAULT;
	460	}
	461	break;
bb2f8a55 VJJ	462	case 'E':{
	463	int32_t cnt = va_arg(ap, int32_t);
	464	const char k = va_arg(ap, const void );
bd8c8ade AK	465	const char __user *u = va_arg(ap,
bd8c8ade AK	466	const void __user *);
bb2f8a55 VJJ	467	errcode = p9pdu_writef(pdu, proto_version, "d",
	468	cnt);
	469	if (!errcode && pdu_write_urw(pdu, k, u, cnt))
	470	errcode = -EFAULT;
	471	}
	472	break;
2c66523f VJJ	473	case 'F':{
	474	int32_t cnt = va_arg(ap, int32_t);
	475	const char k = va_arg(ap, const void );
	476	errcode = p9pdu_writef(pdu, proto_version, "d",
	477	cnt);
	478	if (!errcode && pdu_write_readdir(pdu, k, cnt))
	479	errcode = -EFAULT;
	480	}
	481	break;
51a87c55 EVH	482	case 'U':{
	483	int32_t count = va_arg(ap, int32_t);
	484	const char __user *udata =
e45c5405	485	va_arg(ap, const void __user *);
342fee1d SK	486	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	487	count);
51a87c55 EVH	488	if (!errcode && pdu_write_u(pdu, udata, count))
	489	errcode = -EFAULT;
	490	}
	491	break;
ace51c4d	492	case 'T':{
b76225e2	493	uint16_t nwname = va_arg(ap, int);
ace51c4d EVH	494	const char wnames = va_arg(ap, const char );
ace51c4d EVH	495
342fee1d SK	496	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	497	nwname);
ace51c4d EVH	498	if (!errcode) {
	499	int i;
	500
	501	for (i = 0; i < nwname; i++) {
	502	errcode =
342fee1d SK	503	p9pdu_writef(pdu,
342fee1d SK	504	proto_version,
ace51c4d EVH	505	"s",
	506	wnames[i]);
	507	if (errcode)
	508	break;
	509	}
	510	}
	511	}
	512	break;
	513	case 'R':{
	514	int16_t nwqid = va_arg(ap, int);
	515	struct p9_qid *wqids =
	516	va_arg(ap, struct p9_qid *);
	517
342fee1d SK	518	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	519	nwqid);
ace51c4d EVH	520	if (!errcode) {
	521	int i;
	522
	523	for (i = 0; i < nwqid; i++) {
	524	errcode =
342fee1d SK	525	p9pdu_writef(pdu,
342fee1d SK	526	proto_version,
ace51c4d EVH	527	"Q",
	528	&wqids[i]);
	529	if (errcode)
	530	break;
	531	}
	532	}
	533	}
	534	break;
87d7845a SK	535	case 'I':{
	536	struct p9_iattr_dotl *p9attr = va_arg(ap,
	537	struct p9_iattr_dotl *);
	538
	539	errcode = p9pdu_writef(pdu, proto_version,
	540	"ddddqqqqq",
	541	p9attr->valid,
	542	p9attr->mode,
	543	p9attr->uid,
	544	p9attr->gid,
	545	p9attr->size,
	546	p9attr->atime_sec,
	547	p9attr->atime_nsec,
	548	p9attr->mtime_sec,
	549	p9attr->mtime_nsec);
	550	}
	551	break;
ace51c4d	552	case '?':
c56e4acf SK	553	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	554	(proto_version != p9_proto_2000L))
ace51c4d EVH	555	return 0;
	556	break;
	557	default:
	558	BUG();
	559	break;
	560	}
	561
	562	if (errcode)
	563	break;
	564	}
	565
	566	return errcode;
	567	}
	568
342fee1d	569	int p9pdu_readf(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	570	{
	571	va_list ap;
	572	int ret;
	573
	574	va_start(ap, fmt);
342fee1d	575	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
ace51c4d EVH	576	va_end(ap);
	577
	578	return ret;
	579	}
	580
	581	static int
342fee1d	582	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	583	{
	584	va_list ap;
	585	int ret;
	586
	587	va_start(ap, fmt);
342fee1d	588	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
ace51c4d EVH	589	va_end(ap);
	590
	591	return ret;
	592	}
51a87c55	593
342fee1d	594	int p9stat_read(char buf, int len, struct p9_wstat st, int proto_version)
02da398b EVH	595	{
02da398b EVH	596	struct p9_fcall fake_pdu;
e7f4b8f1	597	int ret;
02da398b EVH	598
	599	fake_pdu.size = len;
	600	fake_pdu.capacity = len;
	601	fake_pdu.sdata = buf;
	602	fake_pdu.offset = 0;
	603
342fee1d	604	ret = p9pdu_readf(&fake_pdu, proto_version, "S", st);
e7f4b8f1 EVH	605	if (ret) {
e7f4b8f1 EVH	606	P9_DPRINTK(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
e660a828	607	P9_DUMP_PKT(0, &fake_pdu);
e7f4b8f1 EVH	608	}
	609
	610	return ret;
02da398b EVH	611	}
	612	EXPORT_SYMBOL(p9stat_read);
	613
51a87c55 EVH	614	int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
51a87c55 EVH	615	{
9bb6c10a	616	pdu->id = type;
51a87c55 EVH	617	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
	618	}
	619
	620	int p9pdu_finalize(struct p9_fcall *pdu)
	621	{
	622	int size = pdu->size;
	623	int err;
	624
	625	pdu->size = 0;
	626	err = p9pdu_writef(pdu, 0, "d", size);
	627	pdu->size = size;
	628
e660a828	629	P9_DUMP_PKT(0, pdu);
e7f4b8f1 EVH	630	P9_DPRINTK(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n", pdu->size,
	631	pdu->id, pdu->tag);
	632
51a87c55 EVH	633	return err;
	634	}
	635
	636	void p9pdu_reset(struct p9_fcall *pdu)
	637	{
	638	pdu->offset = 0;
	639	pdu->size = 0;
022cae36 VJJ	640	pdu->private = NULL;
	641	pdu->pubuf = NULL;
	642	pdu->pkbuf = NULL;
	643	pdu->pbuf_size = 0;
51a87c55	644	}
7751bdb3 SK	645
	646	int p9dirent_read(char buf, int len, struct p9_dirent dirent,
	647	int proto_version)
	648	{
	649	struct p9_fcall fake_pdu;
	650	int ret;
	651	char *nameptr;
	652
	653	fake_pdu.size = len;
	654	fake_pdu.capacity = len;
	655	fake_pdu.sdata = buf;
	656	fake_pdu.offset = 0;
	657
	658	ret = p9pdu_readf(&fake_pdu, proto_version, "Qqbs", &dirent->qid,
	659	&dirent->d_off, &dirent->d_type, &nameptr);
	660	if (ret) {
	661	P9_DPRINTK(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
e660a828	662	P9_DUMP_PKT(1, &fake_pdu);
7751bdb3 SK	663	goto out;
	664	}
	665
	666	strcpy(dirent->d_name, nameptr);
1b0bcbcf	667	kfree(nameptr);
7751bdb3 SK	668
	669	out:
	670	return fake_pdu.offset;
	671	}
	672	EXPORT_SYMBOL(p9dirent_read);