OpenCloudOS-Kernel/net/9p/client.c

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/*
* net/9p/clnt.c
*
* 9P Client
*
* Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
*
* 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/fs.h>
#include <linux/poll.h>
#include <linux/idr.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <net/9p/9p.h>
#include <linux/parser.h>
#include <net/9p/transport.h>
#include <net/9p/client.h>
static struct p9_fid *p9_fid_create(struct p9_client *clnt);
static void p9_fid_destroy(struct p9_fid *fid);
static struct p9_stat *p9_clone_stat(struct p9_stat *st, int dotu);
/*
* Client Option Parsing (code inspired by NFS code)
* - a little lazy - parse all client options
*/
enum {
Opt_msize,
Opt_trans,
Opt_legacy,
Opt_err,
};
static match_table_t tokens = {
{Opt_msize, "msize=%u"},
{Opt_legacy, "noextend"},
{Opt_trans, "trans=%s"},
{Opt_err, NULL},
};
/**
* v9fs_parse_options - parse mount options into session structure
* @options: options string passed from mount
* @v9ses: existing v9fs session information
*
* Return 0 upon success, -ERRNO upon failure
*/
static int parse_opts(char *opts, struct p9_client *clnt)
{
char *options;
char *p;
substring_t args[MAX_OPT_ARGS];
int option;
int ret = 0;
clnt->trans_mod = v9fs_default_trans();
clnt->dotu = 1;
clnt->msize = 8192;
if (!opts)
return 0;
options = kstrdup(opts, GFP_KERNEL);
if (!options) {
P9_DPRINTK(P9_DEBUG_ERROR,
"failed to allocate copy of option string\n");
return -ENOMEM;
}
while ((p = strsep(&options, ",")) != NULL) {
int token;
if (!*p)
continue;
token = match_token(p, tokens, args);
if (token < Opt_trans) {
int r = match_int(&args[0], &option);
if (r < 0) {
P9_DPRINTK(P9_DEBUG_ERROR,
"integer field, but no integer?\n");
ret = r;
continue;
}
}
switch (token) {
case Opt_msize:
clnt->msize = option;
break;
case Opt_trans:
clnt->trans_mod = v9fs_match_trans(&args[0]);
break;
case Opt_legacy:
clnt->dotu = 0;
break;
default:
continue;
}
}
kfree(options);
return ret;
}
/**
* p9_client_rpc - sends 9P request and waits until a response is available.
* The function can be interrupted.
* @c: client data
* @tc: request to be sent
* @rc: pointer where a pointer to the response is stored
*/
int
p9_client_rpc(struct p9_client *c, struct p9_fcall *tc,
struct p9_fcall **rc)
{
return c->trans->rpc(c->trans, tc, rc);
}
struct p9_client *p9_client_create(const char *dev_name, char *options)
{
int err, n;
struct p9_client *clnt;
struct p9_fcall *tc, *rc;
struct p9_str *version;
err = 0;
tc = NULL;
rc = NULL;
clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
if (!clnt)
return ERR_PTR(-ENOMEM);
clnt->trans = NULL;
spin_lock_init(&clnt->lock);
INIT_LIST_HEAD(&clnt->fidlist);
clnt->fidpool = p9_idpool_create();
if (IS_ERR(clnt->fidpool)) {
err = PTR_ERR(clnt->fidpool);
clnt->fidpool = NULL;
goto error;
}
err = parse_opts(options, clnt);
if (err < 0)
goto error;
if (clnt->trans_mod == NULL) {
err = -EPROTONOSUPPORT;
P9_DPRINTK(P9_DEBUG_ERROR,
"No transport defined or default transport\n");
goto error;
}
P9_DPRINTK(P9_DEBUG_9P, "clnt %p trans %p msize %d dotu %d\n",
clnt, clnt->trans_mod, clnt->msize, clnt->dotu);
clnt->trans = clnt->trans_mod->create(dev_name, options, clnt->msize,
clnt->dotu);
if (IS_ERR(clnt->trans)) {
err = PTR_ERR(clnt->trans);
clnt->trans = NULL;
goto error;
}
if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
tc = p9_create_tversion(clnt->msize, clnt->dotu?"9P2000.u":"9P2000");
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
version = &rc->params.rversion.version;
if (version->len == 8 && !memcmp(version->str, "9P2000.u", 8))
clnt->dotu = 1;
else if (version->len == 6 && !memcmp(version->str, "9P2000", 6))
clnt->dotu = 0;
else {
err = -EREMOTEIO;
goto error;
}
n = rc->params.rversion.msize;
if (n < clnt->msize)
clnt->msize = n;
kfree(tc);
kfree(rc);
return clnt;
error:
kfree(tc);
kfree(rc);
p9_client_destroy(clnt);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_create);
void p9_client_destroy(struct p9_client *clnt)
{
struct p9_fid *fid, *fidptr;
P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
if (clnt->trans) {
clnt->trans->close(clnt->trans);
kfree(clnt->trans);
clnt->trans = NULL;
}
list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist)
p9_fid_destroy(fid);
if (clnt->fidpool)
p9_idpool_destroy(clnt->fidpool);
kfree(clnt);
}
EXPORT_SYMBOL(p9_client_destroy);
void p9_client_disconnect(struct p9_client *clnt)
{
P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
clnt->trans->status = Disconnected;
}
EXPORT_SYMBOL(p9_client_disconnect);
struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
9p: attach-per-user The 9P2000 protocol requires the authentication and permission checks to be done in the file server. For that reason every user that accesses the file server tree has to authenticate and attach to the server separately. Multiple users can share the same connection to the server. Currently v9fs does a single attach and executes all I/O operations as a single user. This makes using v9fs in multiuser environment unsafe as it depends on the client doing the permission checking. This patch improves the 9P2000 support by allowing every user to attach separately. The patch defines three modes of access (new mount option 'access'): - attach-per-user (access=user) (default mode for 9P2000.u) If a user tries to access a file served by v9fs for the first time, v9fs sends an attach command to the server (Tattach) specifying the user. If the attach succeeds, the user can access the v9fs tree. As there is no uname->uid (string->integer) mapping yet, this mode works only with the 9P2000.u dialect. - allow only one user to access the tree (access=<uid>) Only the user with uid can access the v9fs tree. Other users that attempt to access it will get EPERM error. - do all operations as a single user (access=any) (default for 9P2000) V9fs does a single attach and all operations are done as a single user. If this mode is selected, the v9fs behavior is identical with the current one. Signed-off-by: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-18 03:31:07 +08:00
char *uname, u32 n_uname, char *aname)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_fid *fid;
P9_DPRINTK(P9_DEBUG_9P, "clnt %p afid %d uname %s aname %s\n",
clnt, afid?afid->fid:-1, uname, aname);
err = 0;
tc = NULL;
rc = NULL;
fid = p9_fid_create(clnt);
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
fid = NULL;
goto error;
}
9p: attach-per-user The 9P2000 protocol requires the authentication and permission checks to be done in the file server. For that reason every user that accesses the file server tree has to authenticate and attach to the server separately. Multiple users can share the same connection to the server. Currently v9fs does a single attach and executes all I/O operations as a single user. This makes using v9fs in multiuser environment unsafe as it depends on the client doing the permission checking. This patch improves the 9P2000 support by allowing every user to attach separately. The patch defines three modes of access (new mount option 'access'): - attach-per-user (access=user) (default mode for 9P2000.u) If a user tries to access a file served by v9fs for the first time, v9fs sends an attach command to the server (Tattach) specifying the user. If the attach succeeds, the user can access the v9fs tree. As there is no uname->uid (string->integer) mapping yet, this mode works only with the 9P2000.u dialect. - allow only one user to access the tree (access=<uid>) Only the user with uid can access the v9fs tree. Other users that attempt to access it will get EPERM error. - do all operations as a single user (access=any) (default for 9P2000) V9fs does a single attach and all operations are done as a single user. If this mode is selected, the v9fs behavior is identical with the current one. Signed-off-by: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-18 03:31:07 +08:00
tc = p9_create_tattach(fid->fid, afid?afid->fid:P9_NOFID, uname, aname,
n_uname, clnt->dotu);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
memmove(&fid->qid, &rc->params.rattach.qid, sizeof(struct p9_qid));
kfree(tc);
kfree(rc);
return fid;
error:
kfree(tc);
kfree(rc);
if (fid)
p9_fid_destroy(fid);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_attach);
9p: attach-per-user The 9P2000 protocol requires the authentication and permission checks to be done in the file server. For that reason every user that accesses the file server tree has to authenticate and attach to the server separately. Multiple users can share the same connection to the server. Currently v9fs does a single attach and executes all I/O operations as a single user. This makes using v9fs in multiuser environment unsafe as it depends on the client doing the permission checking. This patch improves the 9P2000 support by allowing every user to attach separately. The patch defines three modes of access (new mount option 'access'): - attach-per-user (access=user) (default mode for 9P2000.u) If a user tries to access a file served by v9fs for the first time, v9fs sends an attach command to the server (Tattach) specifying the user. If the attach succeeds, the user can access the v9fs tree. As there is no uname->uid (string->integer) mapping yet, this mode works only with the 9P2000.u dialect. - allow only one user to access the tree (access=<uid>) Only the user with uid can access the v9fs tree. Other users that attempt to access it will get EPERM error. - do all operations as a single user (access=any) (default for 9P2000) V9fs does a single attach and all operations are done as a single user. If this mode is selected, the v9fs behavior is identical with the current one. Signed-off-by: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-18 03:31:07 +08:00
struct p9_fid *p9_client_auth(struct p9_client *clnt, char *uname,
u32 n_uname, char *aname)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_fid *fid;
P9_DPRINTK(P9_DEBUG_9P, "clnt %p uname %s aname %s\n", clnt, uname,
aname);
err = 0;
tc = NULL;
rc = NULL;
fid = p9_fid_create(clnt);
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
fid = NULL;
goto error;
}
9p: attach-per-user The 9P2000 protocol requires the authentication and permission checks to be done in the file server. For that reason every user that accesses the file server tree has to authenticate and attach to the server separately. Multiple users can share the same connection to the server. Currently v9fs does a single attach and executes all I/O operations as a single user. This makes using v9fs in multiuser environment unsafe as it depends on the client doing the permission checking. This patch improves the 9P2000 support by allowing every user to attach separately. The patch defines three modes of access (new mount option 'access'): - attach-per-user (access=user) (default mode for 9P2000.u) If a user tries to access a file served by v9fs for the first time, v9fs sends an attach command to the server (Tattach) specifying the user. If the attach succeeds, the user can access the v9fs tree. As there is no uname->uid (string->integer) mapping yet, this mode works only with the 9P2000.u dialect. - allow only one user to access the tree (access=<uid>) Only the user with uid can access the v9fs tree. Other users that attempt to access it will get EPERM error. - do all operations as a single user (access=any) (default for 9P2000) V9fs does a single attach and all operations are done as a single user. If this mode is selected, the v9fs behavior is identical with the current one. Signed-off-by: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-18 03:31:07 +08:00
tc = p9_create_tauth(fid->fid, uname, aname, n_uname, clnt->dotu);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
memmove(&fid->qid, &rc->params.rauth.qid, sizeof(struct p9_qid));
kfree(tc);
kfree(rc);
return fid;
error:
kfree(tc);
kfree(rc);
if (fid)
p9_fid_destroy(fid);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_auth);
struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
int clone)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
struct p9_fid *fid;
P9_DPRINTK(P9_DEBUG_9P, "fid %d nwname %d wname[0] %s\n",
oldfid->fid, nwname, wnames?wnames[0]:NULL);
err = 0;
tc = NULL;
rc = NULL;
clnt = oldfid->clnt;
if (clone) {
fid = p9_fid_create(clnt);
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
fid = NULL;
goto error;
}
fid->uid = oldfid->uid;
} else
fid = oldfid;
tc = p9_create_twalk(oldfid->fid, fid->fid, nwname, wnames);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err) {
if (rc && rc->id == P9_RWALK)
goto clunk_fid;
else
goto error;
}
if (rc->params.rwalk.nwqid != nwname) {
err = -ENOENT;
goto clunk_fid;
}
if (nwname)
memmove(&fid->qid,
&rc->params.rwalk.wqids[rc->params.rwalk.nwqid - 1],
sizeof(struct p9_qid));
else
fid->qid = oldfid->qid;
kfree(tc);
kfree(rc);
return fid;
clunk_fid:
kfree(tc);
kfree(rc);
rc = NULL;
tc = p9_create_tclunk(fid->fid);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
p9_client_rpc(clnt, tc, &rc);
error:
kfree(tc);
kfree(rc);
if (fid && (fid != oldfid))
p9_fid_destroy(fid);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_walk);
int p9_client_open(struct p9_fid *fid, int mode)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d mode %d\n", fid->fid, mode);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
if (fid->mode != -1)
return -EINVAL;
tc = p9_create_topen(fid->fid, mode);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto done;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto done;
fid->mode = mode;
fid->iounit = rc->params.ropen.iounit;
done:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_open);
int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
char *extension)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d name %s perm %d mode %d\n", fid->fid,
name, perm, mode);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
if (fid->mode != -1)
return -EINVAL;
tc = p9_create_tcreate(fid->fid, name, perm, mode, extension,
clnt->dotu);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto done;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto done;
fid->mode = mode;
fid->iounit = rc->params.ropen.iounit;
done:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_fcreate);
int p9_client_clunk(struct p9_fid *fid)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
tc = p9_create_tclunk(fid->fid);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto done;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto done;
p9_fid_destroy(fid);
done:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_clunk);
int p9_client_remove(struct p9_fid *fid)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
tc = p9_create_tremove(fid->fid);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto done;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto done;
p9_fid_destroy(fid);
done:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_remove);
int p9_client_read(struct p9_fid *fid, char *data, u64 offset, u32 count)
{
int err, n, rsize, total;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu %d\n", fid->fid,
(long long unsigned) offset, count);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
total = 0;
rsize = fid->iounit;
if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
rsize = clnt->msize - P9_IOHDRSZ;
do {
if (count < rsize)
rsize = count;
tc = p9_create_tread(fid->fid, offset, rsize);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
n = rc->params.rread.count;
if (n > count)
n = count;
memmove(data, rc->params.rread.data, n);
count -= n;
data += n;
offset += n;
total += n;
kfree(tc);
tc = NULL;
kfree(rc);
rc = NULL;
} while (count > 0 && n == rsize);
return total;
error:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_read);
int p9_client_write(struct p9_fid *fid, char *data, u64 offset, u32 count)
{
int err, n, rsize, total;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
(long long unsigned) offset, count);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
total = 0;
rsize = fid->iounit;
if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
rsize = clnt->msize - P9_IOHDRSZ;
do {
if (count < rsize)
rsize = count;
tc = p9_create_twrite(fid->fid, offset, rsize, data);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
n = rc->params.rread.count;
count -= n;
data += n;
offset += n;
total += n;
kfree(tc);
tc = NULL;
kfree(rc);
rc = NULL;
} while (count > 0);
return total;
error:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_write);
int
p9_client_uread(struct p9_fid *fid, char __user *data, u64 offset, u32 count)
{
int err, n, rsize, total;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
(long long unsigned) offset, count);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
total = 0;
rsize = fid->iounit;
if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
rsize = clnt->msize - P9_IOHDRSZ;
do {
if (count < rsize)
rsize = count;
tc = p9_create_tread(fid->fid, offset, rsize);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
n = rc->params.rread.count;
if (n > count)
n = count;
err = copy_to_user(data, rc->params.rread.data, n);
if (err) {
err = -EFAULT;
goto error;
}
count -= n;
data += n;
offset += n;
total += n;
kfree(tc);
tc = NULL;
kfree(rc);
rc = NULL;
} while (count > 0 && n == rsize);
return total;
error:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_uread);
int
p9_client_uwrite(struct p9_fid *fid, const char __user *data, u64 offset,
u32 count)
{
int err, n, rsize, total;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
(long long unsigned) offset, count);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
total = 0;
rsize = fid->iounit;
if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
rsize = clnt->msize - P9_IOHDRSZ;
do {
if (count < rsize)
rsize = count;
tc = p9_create_twrite_u(fid->fid, offset, rsize, data);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
n = rc->params.rread.count;
count -= n;
data += n;
offset += n;
total += n;
kfree(tc);
tc = NULL;
kfree(rc);
rc = NULL;
} while (count > 0);
return total;
error:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_uwrite);
int p9_client_readn(struct p9_fid *fid, char *data, u64 offset, u32 count)
{
int n, total;
P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
(long long unsigned) offset, count);
n = 0;
total = 0;
while (count) {
n = p9_client_read(fid, data, offset, count);
if (n <= 0)
break;
data += n;
offset += n;
count -= n;
total += n;
}
if (n < 0)
total = n;
return total;
}
EXPORT_SYMBOL(p9_client_readn);
struct p9_stat *p9_client_stat(struct p9_fid *fid)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
struct p9_stat *ret;
P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
err = 0;
tc = NULL;
rc = NULL;
ret = NULL;
clnt = fid->clnt;
tc = p9_create_tstat(fid->fid);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
ret = p9_clone_stat(&rc->params.rstat.stat, clnt->dotu);
if (IS_ERR(ret)) {
err = PTR_ERR(ret);
ret = NULL;
goto error;
}
kfree(tc);
kfree(rc);
return ret;
error:
kfree(tc);
kfree(rc);
kfree(ret);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_stat);
int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
{
int err;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
err = 0;
tc = NULL;
rc = NULL;
clnt = fid->clnt;
tc = p9_create_twstat(fid->fid, wst, clnt->dotu);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto done;
}
err = p9_client_rpc(clnt, tc, &rc);
done:
kfree(tc);
kfree(rc);
return err;
}
EXPORT_SYMBOL(p9_client_wstat);
struct p9_stat *p9_client_dirread(struct p9_fid *fid, u64 offset)
{
int err, n, m;
struct p9_fcall *tc, *rc;
struct p9_client *clnt;
struct p9_stat st, *ret;
P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu\n", fid->fid,
(long long unsigned) offset);
err = 0;
tc = NULL;
rc = NULL;
ret = NULL;
clnt = fid->clnt;
/* if the offset is below or above the current response, free it */
if (offset < fid->rdir_fpos || (fid->rdir_fcall &&
offset >= fid->rdir_fpos+fid->rdir_fcall->params.rread.count)) {
fid->rdir_pos = 0;
if (fid->rdir_fcall)
fid->rdir_fpos += fid->rdir_fcall->params.rread.count;
kfree(fid->rdir_fcall);
fid->rdir_fcall = NULL;
if (offset < fid->rdir_fpos)
fid->rdir_fpos = 0;
}
if (!fid->rdir_fcall) {
n = fid->iounit;
if (!n || n > clnt->msize-P9_IOHDRSZ)
n = clnt->msize - P9_IOHDRSZ;
while (1) {
if (fid->rdir_fcall) {
fid->rdir_fpos +=
fid->rdir_fcall->params.rread.count;
kfree(fid->rdir_fcall);
fid->rdir_fcall = NULL;
}
tc = p9_create_tread(fid->fid, fid->rdir_fpos, n);
if (IS_ERR(tc)) {
err = PTR_ERR(tc);
tc = NULL;
goto error;
}
err = p9_client_rpc(clnt, tc, &rc);
if (err)
goto error;
n = rc->params.rread.count;
if (n == 0)
goto done;
fid->rdir_fcall = rc;
rc = NULL;
if (offset >= fid->rdir_fpos &&
offset < fid->rdir_fpos+n)
break;
}
fid->rdir_pos = 0;
}
m = offset - fid->rdir_fpos;
if (m < 0)
goto done;
n = p9_deserialize_stat(fid->rdir_fcall->params.rread.data + m,
fid->rdir_fcall->params.rread.count - m, &st, clnt->dotu);
if (!n) {
err = -EIO;
goto error;
}
fid->rdir_pos += n;
st.size = n;
ret = p9_clone_stat(&st, clnt->dotu);
if (IS_ERR(ret)) {
err = PTR_ERR(ret);
ret = NULL;
goto error;
}
done:
kfree(tc);
kfree(rc);
return ret;
error:
kfree(tc);
kfree(rc);
kfree(ret);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_dirread);
static struct p9_stat *p9_clone_stat(struct p9_stat *st, int dotu)
{
int n;
char *p;
struct p9_stat *ret;
n = sizeof(struct p9_stat) + st->name.len + st->uid.len + st->gid.len +
st->muid.len;
if (dotu)
n += st->extension.len;
ret = kmalloc(n, GFP_KERNEL);
if (!ret)
return ERR_PTR(-ENOMEM);
memmove(ret, st, sizeof(struct p9_stat));
p = ((char *) ret) + sizeof(struct p9_stat);
memmove(p, st->name.str, st->name.len);
ret->name.str = p;
p += st->name.len;
memmove(p, st->uid.str, st->uid.len);
ret->uid.str = p;
p += st->uid.len;
memmove(p, st->gid.str, st->gid.len);
ret->gid.str = p;
p += st->gid.len;
memmove(p, st->muid.str, st->muid.len);
ret->muid.str = p;
p += st->muid.len;
if (dotu) {
memmove(p, st->extension.str, st->extension.len);
ret->extension.str = p;
p += st->extension.len;
}
return ret;
}
static struct p9_fid *p9_fid_create(struct p9_client *clnt)
{
int err;
struct p9_fid *fid;
P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
if (!fid)
return ERR_PTR(-ENOMEM);
fid->fid = p9_idpool_get(clnt->fidpool);
if (fid->fid < 0) {
err = -ENOSPC;
goto error;
}
memset(&fid->qid, 0, sizeof(struct p9_qid));
fid->mode = -1;
fid->rdir_fpos = 0;
fid->rdir_pos = 0;
fid->rdir_fcall = NULL;
fid->uid = current->fsuid;
fid->clnt = clnt;
fid->aux = NULL;
spin_lock(&clnt->lock);
list_add(&fid->flist, &clnt->fidlist);
spin_unlock(&clnt->lock);
return fid;
error:
kfree(fid);
return ERR_PTR(err);
}
static void p9_fid_destroy(struct p9_fid *fid)
{
struct p9_client *clnt;
P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
clnt = fid->clnt;
p9_idpool_put(fid->fid, clnt->fidpool);
spin_lock(&clnt->lock);
list_del(&fid->flist);
spin_unlock(&clnt->lock);
kfree(fid->rdir_fcall);
kfree(fid);
}