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linux/net/9p/protocol.c
Eric Van Hensbergen 51a87c552d 9p: rework client code to use new protocol support functions
Now that the new protocol functions are in place, this patch switches
the client code to using the new support code.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2008-10-17 11:04:45 -05:00

537 lines
11 KiB
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/uaccess.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include "protocol.h"
#ifndef MIN
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
#define MAX(a, b) (((a) > (b)) ? (a) : (b))
#endif
#ifndef offset_of
#define offset_of(type, memb) \
((unsigned long)(&((type *)0)->memb))
#endif
#ifndef container_of
#define container_of(obj, type, memb) \
((type *)(((char *)obj) - offset_of(type, memb)))
#endif
static int
p9pdu_writef(struct p9_fcall *pdu, int optional, const char *fmt, ...);
#define PACKET_DEBUG 0
void
p9pdu_dump(int way, struct p9_fcall *pdu)
{
int i, n;
u8 *data = pdu->sdata;
int datalen = pdu->size;
char buf[255];
int buflen = 255;
i = n = 0;
if (datalen > (buflen-16))
datalen = buflen-16;
while (i < datalen) {
n += scnprintf(buf + n, buflen - n, "%02x ", data[i]);
if (i%4 == 3)
n += scnprintf(buf + n, buflen - n, " ");
if (i%32 == 31)
n += scnprintf(buf + n, buflen - n, "\n");
i++;
}
n += scnprintf(buf + n, buflen - n, "\n");
if (way)
printk(KERN_NOTICE "[[(%d)[ %s\n", datalen, buf);
else
printk(KERN_NOTICE "]](%d)] %s\n", datalen, buf);
}
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);
int err = copy_from_user(&pdu->sdata[pdu->size], udata, len);
if (err)
printk(KERN_WARNING "pdu_write_u returning: %d\n", err);
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)
? - if optional = 1, continue parsing
*/
static int
p9pdu_vreadf(struct p9_fcall *pdu, int optional, 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 *);
if (pdu_read(pdu, val, sizeof(*val))) {
errcode = -EFAULT;
break;
}
*val = cpu_to_le16(*val);
}
break;
case 'd':{
int32_t *val = va_arg(ap, int32_t *);
if (pdu_read(pdu, val, sizeof(*val))) {
errcode = -EFAULT;
break;
}
*val = cpu_to_le32(*val);
}
break;
case 'q':{
int64_t *val = va_arg(ap, int64_t *);
if (pdu_read(pdu, val, sizeof(*val))) {
errcode = -EFAULT;
break;
}
*val = cpu_to_le64(*val);
}
break;
case 's':{
char **ptr = va_arg(ap, char **);
int16_t len;
int size;
errcode = p9pdu_readf(pdu, optional, "w", &len);
if (errcode)
break;
size = MAX(len, 0);
*ptr = kmalloc(size + 1, GFP_KERNEL);
if (*ptr == NULL) {
errcode = -EFAULT;
break;
}
if (pdu_read(pdu, *ptr, size)) {
errcode = -EFAULT;
kfree(*ptr);
*ptr = NULL;
} else
(*ptr)[size] = 0;
}
break;
case 'Q':{
struct p9_qid *qid =
va_arg(ap, struct p9_qid *);
errcode = p9pdu_readf(pdu, optional, "bdq",
&qid->type, &qid->version,
&qid->path);
}
break;
case 'S':{
struct p9_wstat *stbuf =
va_arg(ap, struct p9_wstat *);
stbuf->extension = NULL;
stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
-1;
errcode =
p9pdu_readf(pdu, optional,
"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':{
int32_t *count = va_arg(ap, int32_t *);
void **data = va_arg(ap, void **);
errcode =
p9pdu_readf(pdu, optional, "d", count);
if (!errcode) {
*count =
MIN(*count,
pdu->size - pdu->offset);
*data = &pdu->sdata[pdu->offset];
}
}
break;
case 'T':{
int16_t *nwname = va_arg(ap, int16_t *);
char ***wnames = va_arg(ap, char ***);
errcode =
p9pdu_readf(pdu, optional, "w", nwname);
if (!errcode) {
*wnames =
kmalloc(sizeof(char *) * *nwname,
GFP_KERNEL);
if (!*wnames)
errcode = -ENOMEM;
}
if (!errcode) {
int i;
for (i = 0; i < *nwname; i++) {
errcode =
p9pdu_readf(pdu, optional,
"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, optional, "w", nwqid);
if (!errcode) {
*wqids =
kmalloc(*nwqid *
sizeof(struct p9_qid),
GFP_KERNEL);
if (*wqids == NULL)
errcode = -ENOMEM;
}
if (!errcode) {
int i;
for (i = 0; i < *nwqid; i++) {
errcode =
p9pdu_readf(pdu, optional,
"Q",
&(*wqids)[i]);
if (errcode)
break;
}
}
if (errcode) {
kfree(*wqids);
*wqids = NULL;
}
}
break;
case '?':
if (!optional)
return 0;
break;
default:
BUG();
break;
}
if (errcode)
break;
}
return errcode;
}
int
p9pdu_vwritef(struct p9_fcall *pdu, int optional, 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':{
int16_t val = va_arg(ap, int);
if (pdu_write(pdu, &val, sizeof(val)))
errcode = -EFAULT;
}
break;
case 'd':{
int32_t val = va_arg(ap, int32_t);
if (pdu_write(pdu, &val, sizeof(val)))
errcode = -EFAULT;
}
break;
case 'q':{
int64_t val = va_arg(ap, int64_t);
if (pdu_write(pdu, &val, sizeof(val)))
errcode = -EFAULT;
}
break;
case 's':{
const char *ptr = va_arg(ap, const char *);
int16_t len = 0;
if (ptr)
len = MIN(strlen(ptr), USHORT_MAX);
errcode = p9pdu_writef(pdu, optional, "w", len);
if (!errcode && pdu_write(pdu, ptr, len))
errcode = -EFAULT;
}
break;
case 'Q':{
const struct p9_qid *qid =
va_arg(ap, const struct p9_qid *);
errcode =
p9pdu_writef(pdu, optional, "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, optional,
"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':{
int32_t count = va_arg(ap, int32_t);
const void *data = va_arg(ap, const void *);
errcode =
p9pdu_writef(pdu, optional, "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 *);
errcode =
p9pdu_writef(pdu, optional, "d", count);
if (!errcode && pdu_write_u(pdu, udata, count))
errcode = -EFAULT;
}
break;
case 'T':{
int16_t nwname = va_arg(ap, int);
const char **wnames = va_arg(ap, const char **);
errcode =
p9pdu_writef(pdu, optional, "w", nwname);
if (!errcode) {
int i;
for (i = 0; i < nwname; i++) {
errcode =
p9pdu_writef(pdu, optional,
"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, optional, "w", nwqid);
if (!errcode) {
int i;
for (i = 0; i < nwqid; i++) {
errcode =
p9pdu_writef(pdu, optional,
"Q",
&wqids[i]);
if (errcode)
break;
}
}
}
break;
case '?':
if (!optional)
return 0;
break;
default:
BUG();
break;
}
if (errcode)
break;
}
return errcode;
}
int p9pdu_readf(struct p9_fcall *pdu, int optional, const char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
ret = p9pdu_vreadf(pdu, optional, fmt, ap);
va_end(ap);
return ret;
}
static int
p9pdu_writef(struct p9_fcall *pdu, int optional, const char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
ret = p9pdu_vwritef(pdu, optional, fmt, ap);
va_end(ap);
return ret;
}
int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t 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;
if (PACKET_DEBUG)
p9pdu_dump(0, pdu);
return err;
}
void p9pdu_reset(struct p9_fcall *pdu)
{
pdu->offset = 0;
pdu->size = 0;
}