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linux/net/9p/client.c
Dominique Martinet cf7c33d332
9p: remove dead stores (variable set again without being read) 
The 9p code for some reason used to initialize variables outside of the
declaration, e.g. instead of just initializing the variable like this:

int retval = 0

We would be doing this:

int retval;
retval = 0;

This is perfectly fine and the compiler will just optimize dead stores
anyway, but scan-build seems to think this is a problem and there are
many of these warnings making the output of scan-build full of such
warnings:
fs/9p/vfs_inode.c:916:2: warning: Value stored to 'retval' is never read [deadcode.DeadStores]
        retval = 0;
        ^        ~

I have no strong opinion here, but if we want to regularly run
scan-build we should fix these just to silence the messages.

I've confirmed these all are indeed ok to remove.

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2023-07-20 19:14:50 +00:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* 9P Client
*
* Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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/slab.h>
#include <linux/sched/signal.h>
#include <linux/uaccess.h>
#include <linux/uio.h>
#include <net/9p/9p.h>
#include <linux/parser.h>
#include <linux/seq_file.h>
#include <net/9p/client.h>
#include <net/9p/transport.h>
#include "protocol.h"
#define CREATE_TRACE_POINTS
#include <trace/events/9p.h>
/* DEFAULT MSIZE = 32 pages worth of payload + P9_HDRSZ +
* room for write (16 extra) or read (11 extra) operands.
*/
#define DEFAULT_MSIZE ((128 * 1024) + P9_IOHDRSZ)
/* Client Option Parsing (code inspired by NFS code)
* - a little lazy - parse all client options
*/
enum {
Opt_msize,
Opt_trans,
Opt_legacy,
Opt_version,
Opt_err,
};
static const match_table_t tokens = {
{Opt_msize, "msize=%u"},
{Opt_legacy, "noextend"},
{Opt_trans, "trans=%s"},
{Opt_version, "version=%s"},
{Opt_err, NULL},
};
inline int p9_is_proto_dotl(struct p9_client *clnt)
{
return clnt->proto_version == p9_proto_2000L;
}
EXPORT_SYMBOL(p9_is_proto_dotl);
inline int p9_is_proto_dotu(struct p9_client *clnt)
{
return clnt->proto_version == p9_proto_2000u;
}
EXPORT_SYMBOL(p9_is_proto_dotu);
int p9_show_client_options(struct seq_file *m, struct p9_client *clnt)
{
if (clnt->msize != DEFAULT_MSIZE)
seq_printf(m, ",msize=%u", clnt->msize);
seq_printf(m, ",trans=%s", clnt->trans_mod->name);
switch (clnt->proto_version) {
case p9_proto_legacy:
seq_puts(m, ",noextend");
break;
case p9_proto_2000u:
seq_puts(m, ",version=9p2000.u");
break;
case p9_proto_2000L:
/* Default */
break;
}
if (clnt->trans_mod->show_options)
return clnt->trans_mod->show_options(m, clnt);
return 0;
}
EXPORT_SYMBOL(p9_show_client_options);
/* Some error codes are taken directly from the server replies,
* make sure they are valid.
*/
static int safe_errno(int err)
{
if (err > 0 || err < -MAX_ERRNO) {
p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
return -EPROTO;
}
return err;
}
/* Interpret mount option for protocol version */
static int get_protocol_version(char *s)
{
int version = -EINVAL;
if (!strcmp(s, "9p2000")) {
version = p9_proto_legacy;
p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
} else if (!strcmp(s, "9p2000.u")) {
version = p9_proto_2000u;
p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
} else if (!strcmp(s, "9p2000.L")) {
version = p9_proto_2000L;
p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
} else {
pr_info("Unknown protocol version %s\n", s);
}
return version;
}
/**
* parse_opts - parse mount options into client structure
* @opts: options string passed from mount
* @clnt: existing v9fs client information
*
* Return 0 upon success, -ERRNO upon failure
*/
static int parse_opts(char *opts, struct p9_client *clnt)
{
char *options, *tmp_options;
char *p;
substring_t args[MAX_OPT_ARGS];
int option;
char *s;
int ret = 0;
clnt->proto_version = p9_proto_2000L;
clnt->msize = DEFAULT_MSIZE;
if (!opts)
return 0;
tmp_options = kstrdup(opts, GFP_KERNEL);
if (!tmp_options)
return -ENOMEM;
options = tmp_options;
while ((p = strsep(&options, ",")) != NULL) {
int token, r;
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case Opt_msize:
r = match_int(&args[0], &option);
if (r < 0) {
p9_debug(P9_DEBUG_ERROR,
"integer field, but no integer?\n");
ret = r;
continue;
}
if (option < 4096) {
p9_debug(P9_DEBUG_ERROR,
"msize should be at least 4k\n");
ret = -EINVAL;
continue;
}
clnt->msize = option;
break;
case Opt_trans:
s = match_strdup(&args[0]);
if (!s) {
ret = -ENOMEM;
p9_debug(P9_DEBUG_ERROR,
"problem allocating copy of trans arg\n");
goto free_and_return;
}
v9fs_put_trans(clnt->trans_mod);
clnt->trans_mod = v9fs_get_trans_by_name(s);
if (!clnt->trans_mod) {
pr_info("Could not find request transport: %s\n",
s);
ret = -EINVAL;
}
kfree(s);
break;
case Opt_legacy:
clnt->proto_version = p9_proto_legacy;
break;
case Opt_version:
s = match_strdup(&args[0]);
if (!s) {
ret = -ENOMEM;
p9_debug(P9_DEBUG_ERROR,
"problem allocating copy of version arg\n");
goto free_and_return;
}
r = get_protocol_version(s);
if (r < 0)
ret = r;
else
clnt->proto_version = r;
kfree(s);
break;
default:
continue;
}
}
free_and_return:
if (ret)
v9fs_put_trans(clnt->trans_mod);
kfree(tmp_options);
return ret;
}
static int p9_fcall_init(struct p9_client *c, struct p9_fcall *fc,
int alloc_msize)
{
if (likely(c->fcall_cache) && alloc_msize == c->msize) {
fc->sdata = kmem_cache_alloc(c->fcall_cache, GFP_NOFS);
fc->cache = c->fcall_cache;
} else {
fc->sdata = kmalloc(alloc_msize, GFP_NOFS);
fc->cache = NULL;
}
if (!fc->sdata)
return -ENOMEM;
fc->capacity = alloc_msize;
return 0;
}
void p9_fcall_fini(struct p9_fcall *fc)
{
/* sdata can be NULL for interrupted requests in trans_rdma,
* and kmem_cache_free does not do NULL-check for us
*/
if (unlikely(!fc->sdata))
return;
if (fc->cache)
kmem_cache_free(fc->cache, fc->sdata);
else
kfree(fc->sdata);
}
EXPORT_SYMBOL(p9_fcall_fini);
static struct kmem_cache *p9_req_cache;
/**
* p9_tag_alloc - Allocate a new request.
* @c: Client session.
* @type: Transaction type.
* @t_size: Buffer size for holding this request
* (automatic calculation by format template if 0).
* @r_size: Buffer size for holding server's reply on this request
* (automatic calculation by format template if 0).
* @fmt: Format template for assembling 9p request message
* (see p9pdu_vwritef).
* @ap: Variable arguments to be fed to passed format template
* (see p9pdu_vwritef).
*
* Context: Process context.
* Return: Pointer to new request.
*/
static struct p9_req_t *
p9_tag_alloc(struct p9_client *c, int8_t type, uint t_size, uint r_size,
const char *fmt, va_list ap)
{
struct p9_req_t *req = kmem_cache_alloc(p9_req_cache, GFP_NOFS);
int alloc_tsize;
int alloc_rsize;
int tag;
va_list apc;
va_copy(apc, ap);
alloc_tsize = min_t(size_t, c->msize,
t_size ?: p9_msg_buf_size(c, type, fmt, apc));
va_end(apc);
alloc_rsize = min_t(size_t, c->msize,
r_size ?: p9_msg_buf_size(c, type + 1, fmt, ap));
if (!req)
return ERR_PTR(-ENOMEM);
if (p9_fcall_init(c, &req->tc, alloc_tsize))
goto free_req;
if (p9_fcall_init(c, &req->rc, alloc_rsize))
goto free;
p9pdu_reset(&req->tc);
p9pdu_reset(&req->rc);
req->t_err = 0;
req->status = REQ_STATUS_ALLOC;
/* refcount needs to be set to 0 before inserting into the idr
* so p9_tag_lookup does not accept a request that is not fully
* initialized. refcount_set to 2 below will mark request ready.
*/
refcount_set(&req->refcount, 0);
init_waitqueue_head(&req->wq);
INIT_LIST_HEAD(&req->req_list);
idr_preload(GFP_NOFS);
spin_lock_irq(&c->lock);
if (type == P9_TVERSION)
tag = idr_alloc(&c->reqs, req, P9_NOTAG, P9_NOTAG + 1,
GFP_NOWAIT);
else
tag = idr_alloc(&c->reqs, req, 0, P9_NOTAG, GFP_NOWAIT);
req->tc.tag = tag;
spin_unlock_irq(&c->lock);
idr_preload_end();
if (tag < 0)
goto free;
/* Init ref to two because in the general case there is one ref
* that is put asynchronously by a writer thread, one ref
* temporarily given by p9_tag_lookup and put by p9_client_cb
* in the recv thread, and one ref put by p9_req_put in the
* main thread. The only exception is virtio that does not use
* p9_tag_lookup but does not have a writer thread either
* (the write happens synchronously in the request/zc_request
* callback), so p9_client_cb eats the second ref there
* as the pointer is duplicated directly by virtqueue_add_sgs()
*/
refcount_set(&req->refcount, 2);
return req;
free:
p9_fcall_fini(&req->tc);
p9_fcall_fini(&req->rc);
free_req:
kmem_cache_free(p9_req_cache, req);
return ERR_PTR(-ENOMEM);
}
/**
* p9_tag_lookup - Look up a request by tag.
* @c: Client session.
* @tag: Transaction ID.
*
* Context: Any context.
* Return: A request, or %NULL if there is no request with that tag.
*/
struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
{
struct p9_req_t *req;
rcu_read_lock();
again:
req = idr_find(&c->reqs, tag);
if (req) {
/* We have to be careful with the req found under rcu_read_lock
* Thanks to SLAB_TYPESAFE_BY_RCU we can safely try to get the
* ref again without corrupting other data, then check again
* that the tag matches once we have the ref
*/
if (!p9_req_try_get(req))
goto again;
if (req->tc.tag != tag) {
p9_req_put(c, req);
goto again;
}
}
rcu_read_unlock();
return req;
}
EXPORT_SYMBOL(p9_tag_lookup);
/**
* p9_tag_remove - Remove a tag.
* @c: Client session.
* @r: Request of reference.
*
* Context: Any context.
*/
static void p9_tag_remove(struct p9_client *c, struct p9_req_t *r)
{
unsigned long flags;
u16 tag = r->tc.tag;
p9_debug(P9_DEBUG_MUX, "freeing clnt %p req %p tag: %d\n", c, r, tag);
spin_lock_irqsave(&c->lock, flags);
idr_remove(&c->reqs, tag);
spin_unlock_irqrestore(&c->lock, flags);
}
int p9_req_put(struct p9_client *c, struct p9_req_t *r)
{
if (refcount_dec_and_test(&r->refcount)) {
p9_tag_remove(c, r);
p9_fcall_fini(&r->tc);
p9_fcall_fini(&r->rc);
kmem_cache_free(p9_req_cache, r);
return 1;
}
return 0;
}
EXPORT_SYMBOL(p9_req_put);
/**
* p9_tag_cleanup - cleans up tags structure and reclaims resources
* @c: v9fs client struct
*
* This frees resources associated with the tags structure
*
*/
static void p9_tag_cleanup(struct p9_client *c)
{
struct p9_req_t *req;
int id;
rcu_read_lock();
idr_for_each_entry(&c->reqs, req, id) {
pr_info("Tag %d still in use\n", id);
if (p9_req_put(c, req) == 0)
pr_warn("Packet with tag %d has still references",
req->tc.tag);
}
rcu_read_unlock();
}
/**
* p9_client_cb - call back from transport to client
* @c: client state
* @req: request received
* @status: request status, one of REQ_STATUS_*
*
*/
void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status)
{
p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc.tag);
/* This barrier is needed to make sure any change made to req before
* the status change is visible to another thread
*/
smp_wmb();
WRITE_ONCE(req->status, status);
wake_up(&req->wq);
p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc.tag);
p9_req_put(c, req);
}
EXPORT_SYMBOL(p9_client_cb);
/**
* p9_parse_header - parse header arguments out of a packet
* @pdu: packet to parse
* @size: size of packet
* @type: type of request
* @tag: tag of packet
* @rewind: set if we need to rewind offset afterwards
*/
int
p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type,
int16_t *tag, int rewind)
{
s8 r_type;
s16 r_tag;
s32 r_size;
int offset = pdu->offset;
int err;
pdu->offset = 0;
err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
if (err)
goto rewind_and_exit;
if (type)
*type = r_type;
if (tag)
*tag = r_tag;
if (size)
*size = r_size;
if (pdu->size != r_size || r_size < 7) {
err = -EINVAL;
goto rewind_and_exit;
}
pdu->id = r_type;
pdu->tag = r_tag;
p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
pdu->size, pdu->id, pdu->tag);
rewind_and_exit:
if (rewind)
pdu->offset = offset;
return err;
}
EXPORT_SYMBOL(p9_parse_header);
/**
* p9_check_errors - check 9p packet for error return and process it
* @c: current client instance
* @req: request to parse and check for error conditions
*
* returns error code if one is discovered, otherwise returns 0
*
* this will have to be more complicated if we have multiple
* error packet types
*/
static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
{
s8 type;
int err;
int ecode;
err = p9_parse_header(&req->rc, NULL, &type, NULL, 0);
if (req->rc.size > req->rc.capacity && !req->rc.zc) {
pr_err("requested packet size too big: %d does not fit %zu (type=%d)\n",
req->rc.size, req->rc.capacity, req->rc.id);
return -EIO;
}
/* dump the response from server
* This should be after check errors which poplulate pdu_fcall.
*/
trace_9p_protocol_dump(c, &req->rc);
if (err) {
p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
return err;
}
if (type != P9_RERROR && type != P9_RLERROR)
return 0;
if (!p9_is_proto_dotl(c)) {
char *ename;
err = p9pdu_readf(&req->rc, c->proto_version, "s?d",
&ename, &ecode);
if (err)
goto out_err;
if (p9_is_proto_dotu(c) && ecode < 512)
err = -ecode;
if (!err) {
err = p9_errstr2errno(ename, strlen(ename));
p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
-ecode, ename);
}
kfree(ename);
} else {
err = p9pdu_readf(&req->rc, c->proto_version, "d", &ecode);
if (err)
goto out_err;
err = -ecode;
p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
}
return err;
out_err:
p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
return err;
}
static struct p9_req_t *
p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
/**
* p9_client_flush - flush (cancel) a request
* @c: client state
* @oldreq: request to cancel
*
* This sents a flush for a particular request and links
* the flush request to the original request. The current
* code only supports a single flush request although the protocol
* allows for multiple flush requests to be sent for a single request.
*
*/
static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
{
struct p9_req_t *req;
s16 oldtag;
int err;
err = p9_parse_header(&oldreq->tc, NULL, NULL, &oldtag, 1);
if (err)
return err;
p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
if (IS_ERR(req))
return PTR_ERR(req);
/* if we haven't received a response for oldreq,
* remove it from the list
*/
if (READ_ONCE(oldreq->status) == REQ_STATUS_SENT) {
if (c->trans_mod->cancelled)
c->trans_mod->cancelled(c, oldreq);
}
p9_req_put(c, req);
return 0;
}
static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
int8_t type, uint t_size, uint r_size,
const char *fmt, va_list ap)
{
int err;
struct p9_req_t *req;
va_list apc;
p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
/* we allow for any status other than disconnected */
if (c->status == Disconnected)
return ERR_PTR(-EIO);
/* if status is begin_disconnected we allow only clunk request */
if (c->status == BeginDisconnect && type != P9_TCLUNK)
return ERR_PTR(-EIO);
va_copy(apc, ap);
req = p9_tag_alloc(c, type, t_size, r_size, fmt, apc);
va_end(apc);
if (IS_ERR(req))
return req;
/* marshall the data */
p9pdu_prepare(&req->tc, req->tc.tag, type);
err = p9pdu_vwritef(&req->tc, c->proto_version, fmt, ap);
if (err)
goto reterr;
p9pdu_finalize(c, &req->tc);
trace_9p_client_req(c, type, req->tc.tag);
return req;
reterr:
p9_req_put(c, req);
/* We have to put also the 2nd reference as it won't be used */
p9_req_put(c, req);
return ERR_PTR(err);
}
/**
* p9_client_rpc - issue a request and wait for a response
* @c: client session
* @type: type of request
* @fmt: protocol format string (see protocol.c)
*
* Returns request structure (which client must free using p9_req_put)
*/
static struct p9_req_t *
p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
{
va_list ap;
int sigpending, err;
unsigned long flags;
struct p9_req_t *req;
/* Passing zero for tsize/rsize to p9_client_prepare_req() tells it to
* auto determine an appropriate (small) request/response size
* according to actual message data being sent. Currently RDMA
* transport is excluded from this response message size optimization,
* as it would not cope with it, due to its pooled response buffers
* (using an optimized request size for RDMA as well though).
*/
const uint tsize = 0;
const uint rsize = c->trans_mod->pooled_rbuffers ? c->msize : 0;
va_start(ap, fmt);
req = p9_client_prepare_req(c, type, tsize, rsize, fmt, ap);
va_end(ap);
if (IS_ERR(req))
return req;
req->tc.zc = false;
req->rc.zc = false;
if (signal_pending(current)) {
sigpending = 1;
clear_thread_flag(TIF_SIGPENDING);
} else {
sigpending = 0;
}
err = c->trans_mod->request(c, req);
if (err < 0) {
/* write won't happen */
p9_req_put(c, req);
if (err != -ERESTARTSYS && err != -EFAULT)
c->status = Disconnected;
goto recalc_sigpending;
}
again:
/* Wait for the response */
err = wait_event_killable(req->wq,
READ_ONCE(req->status) >= REQ_STATUS_RCVD);
/* Make sure our req is coherent with regard to updates in other
* threads - echoes to wmb() in the callback
*/
smp_rmb();
if (err == -ERESTARTSYS && c->status == Connected &&
type == P9_TFLUSH) {
sigpending = 1;
clear_thread_flag(TIF_SIGPENDING);
goto again;
}
if (READ_ONCE(req->status) == REQ_STATUS_ERROR) {
p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
err = req->t_err;
}
if (err == -ERESTARTSYS && c->status == Connected) {
p9_debug(P9_DEBUG_MUX, "flushing\n");
sigpending = 1;
clear_thread_flag(TIF_SIGPENDING);
if (c->trans_mod->cancel(c, req))
p9_client_flush(c, req);
/* if we received the response anyway, don't signal error */
if (READ_ONCE(req->status) == REQ_STATUS_RCVD)
err = 0;
}
recalc_sigpending:
if (sigpending) {
spin_lock_irqsave(&current->sighand->siglock, flags);
recalc_sigpending();
spin_unlock_irqrestore(&current->sighand->siglock, flags);
}
if (err < 0)
goto reterr;
err = p9_check_errors(c, req);
trace_9p_client_res(c, type, req->rc.tag, err);
if (!err)
return req;
reterr:
p9_req_put(c, req);
return ERR_PTR(safe_errno(err));
}
/**
* p9_client_zc_rpc - issue a request and wait for a response
* @c: client session
* @type: type of request
* @uidata: destination for zero copy read
* @uodata: source for zero copy write
* @inlen: read buffer size
* @olen: write buffer size
* @in_hdrlen: reader header size, This is the size of response protocol data
* @fmt: protocol format string (see protocol.c)
*
* Returns request structure (which client must free using p9_req_put)
*/
static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
struct iov_iter *uidata,
struct iov_iter *uodata,
int inlen, int olen, int in_hdrlen,
const char *fmt, ...)
{
va_list ap;
int sigpending, err;
unsigned long flags;
struct p9_req_t *req;
va_start(ap, fmt);
/* We allocate a inline protocol data of only 4k bytes.
* The actual content is passed in zero-copy fashion.
*/
req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, P9_ZC_HDR_SZ, fmt, ap);
va_end(ap);
if (IS_ERR(req))
return req;
req->tc.zc = true;
req->rc.zc = true;
if (signal_pending(current)) {
sigpending = 1;
clear_thread_flag(TIF_SIGPENDING);
} else {
sigpending = 0;
}
err = c->trans_mod->zc_request(c, req, uidata, uodata,
inlen, olen, in_hdrlen);
if (err < 0) {
if (err == -EIO)
c->status = Disconnected;
if (err != -ERESTARTSYS)
goto recalc_sigpending;
}
if (READ_ONCE(req->status) == REQ_STATUS_ERROR) {
p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
err = req->t_err;
}
if (err == -ERESTARTSYS && c->status == Connected) {
p9_debug(P9_DEBUG_MUX, "flushing\n");
sigpending = 1;
clear_thread_flag(TIF_SIGPENDING);
if (c->trans_mod->cancel(c, req))
p9_client_flush(c, req);
/* if we received the response anyway, don't signal error */
if (READ_ONCE(req->status) == REQ_STATUS_RCVD)
err = 0;
}
recalc_sigpending:
if (sigpending) {
spin_lock_irqsave(&current->sighand->siglock, flags);
recalc_sigpending();
spin_unlock_irqrestore(&current->sighand->siglock, flags);
}
if (err < 0)
goto reterr;
err = p9_check_errors(c, req);
trace_9p_client_res(c, type, req->rc.tag, err);
if (!err)
return req;
reterr:
p9_req_put(c, req);
return ERR_PTR(safe_errno(err));
}
static struct p9_fid *p9_fid_create(struct p9_client *clnt)
{
int ret;
struct p9_fid *fid;
p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
fid = kzalloc(sizeof(*fid), GFP_KERNEL);
if (!fid)
return NULL;
fid->mode = -1;
fid->uid = current_fsuid();
fid->clnt = clnt;
refcount_set(&fid->count, 1);
idr_preload(GFP_KERNEL);
spin_lock_irq(&clnt->lock);
ret = idr_alloc_u32(&clnt->fids, fid, &fid->fid, P9_NOFID - 1,
GFP_NOWAIT);
spin_unlock_irq(&clnt->lock);
idr_preload_end();
if (!ret) {
trace_9p_fid_ref(fid, P9_FID_REF_CREATE);
return fid;
}
kfree(fid);
return NULL;
}
static void p9_fid_destroy(struct p9_fid *fid)
{
struct p9_client *clnt;
unsigned long flags;
p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
trace_9p_fid_ref(fid, P9_FID_REF_DESTROY);
clnt = fid->clnt;
spin_lock_irqsave(&clnt->lock, flags);
idr_remove(&clnt->fids, fid->fid);
spin_unlock_irqrestore(&clnt->lock, flags);
kfree(fid->rdir);
kfree(fid);
}
/* We also need to export tracepoint symbols for tracepoint_enabled() */
EXPORT_TRACEPOINT_SYMBOL(9p_fid_ref);
void do_trace_9p_fid_get(struct p9_fid *fid)
{
trace_9p_fid_ref(fid, P9_FID_REF_GET);
}
EXPORT_SYMBOL(do_trace_9p_fid_get);
void do_trace_9p_fid_put(struct p9_fid *fid)
{
trace_9p_fid_ref(fid, P9_FID_REF_PUT);
}
EXPORT_SYMBOL(do_trace_9p_fid_put);
static int p9_client_version(struct p9_client *c)
{
int err;
struct p9_req_t *req;
char *version = NULL;
int msize;
p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
c->msize, c->proto_version);
switch (c->proto_version) {
case p9_proto_2000L:
req = p9_client_rpc(c, P9_TVERSION, "ds",
c->msize, "9P2000.L");
break;
case p9_proto_2000u:
req = p9_client_rpc(c, P9_TVERSION, "ds",
c->msize, "9P2000.u");
break;
case p9_proto_legacy:
req = p9_client_rpc(c, P9_TVERSION, "ds",
c->msize, "9P2000");
break;
default:
return -EINVAL;
}
if (IS_ERR(req))
return PTR_ERR(req);
err = p9pdu_readf(&req->rc, c->proto_version, "ds", &msize, &version);
if (err) {
p9_debug(P9_DEBUG_9P, "version error %d\n", err);
trace_9p_protocol_dump(c, &req->rc);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
if (!strncmp(version, "9P2000.L", 8)) {
c->proto_version = p9_proto_2000L;
} else if (!strncmp(version, "9P2000.u", 8)) {
c->proto_version = p9_proto_2000u;
} else if (!strncmp(version, "9P2000", 6)) {
c->proto_version = p9_proto_legacy;
} else {
p9_debug(P9_DEBUG_ERROR,
"server returned an unknown version: %s\n", version);
err = -EREMOTEIO;
goto error;
}
if (msize < 4096) {
p9_debug(P9_DEBUG_ERROR,
"server returned a msize < 4096: %d\n", msize);
err = -EREMOTEIO;
goto error;
}
if (msize < c->msize)
c->msize = msize;
error:
kfree(version);
p9_req_put(c, req);
return err;
}
struct p9_client *p9_client_create(const char *dev_name, char *options)
{
int err;
struct p9_client *clnt;
char *client_id;
clnt = kmalloc(sizeof(*clnt), GFP_KERNEL);
if (!clnt)
return ERR_PTR(-ENOMEM);
clnt->trans_mod = NULL;
clnt->trans = NULL;
clnt->fcall_cache = NULL;
client_id = utsname()->nodename;
memcpy(clnt->name, client_id, strlen(client_id) + 1);
spin_lock_init(&clnt->lock);
idr_init(&clnt->fids);
idr_init(&clnt->reqs);
err = parse_opts(options, clnt);
if (err < 0)
goto free_client;
if (!clnt->trans_mod)
clnt->trans_mod = v9fs_get_default_trans();
if (!clnt->trans_mod) {
err = -EPROTONOSUPPORT;
p9_debug(P9_DEBUG_ERROR,
"No transport defined or default transport\n");
goto free_client;
}
p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
err = clnt->trans_mod->create(clnt, dev_name, options);
if (err)
goto put_trans;
if (clnt->msize > clnt->trans_mod->maxsize) {
clnt->msize = clnt->trans_mod->maxsize;
pr_info("Limiting 'msize' to %d as this is the maximum "
"supported by transport %s\n",
clnt->msize, clnt->trans_mod->name
);
}
if (clnt->msize < 4096) {
p9_debug(P9_DEBUG_ERROR,
"Please specify a msize of at least 4k\n");
err = -EINVAL;
goto close_trans;
}
err = p9_client_version(clnt);
if (err)
goto close_trans;
/* P9_HDRSZ + 4 is the smallest packet header we can have that is
* followed by data accessed from userspace by read
*/
clnt->fcall_cache =
kmem_cache_create_usercopy("9p-fcall-cache", clnt->msize,
0, 0, P9_HDRSZ + 4,
clnt->msize - (P9_HDRSZ + 4),
NULL);
return clnt;
close_trans:
clnt->trans_mod->close(clnt);
put_trans:
v9fs_put_trans(clnt->trans_mod);
free_client:
kfree(clnt);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_create);
void p9_client_destroy(struct p9_client *clnt)
{
struct p9_fid *fid;
int id;
p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
if (clnt->trans_mod)
clnt->trans_mod->close(clnt);
v9fs_put_trans(clnt->trans_mod);
idr_for_each_entry(&clnt->fids, fid, id) {
pr_info("Found fid %d not clunked\n", fid->fid);
p9_fid_destroy(fid);
}
p9_tag_cleanup(clnt);
kmem_cache_destroy(clnt->fcall_cache);
kfree(clnt);
}
EXPORT_SYMBOL(p9_client_destroy);
void p9_client_disconnect(struct p9_client *clnt)
{
p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
clnt->status = Disconnected;
}
EXPORT_SYMBOL(p9_client_disconnect);
void p9_client_begin_disconnect(struct p9_client *clnt)
{
p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
clnt->status = BeginDisconnect;
}
EXPORT_SYMBOL(p9_client_begin_disconnect);
struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
const char *uname, kuid_t n_uname,
const char *aname)
{
int err;
struct p9_req_t *req;
struct p9_fid *fid;
struct p9_qid qid;
p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
afid ? afid->fid : -1, uname, aname);
fid = p9_fid_create(clnt);
if (!fid) {
err = -ENOMEM;
goto error;
}
fid->uid = n_uname;
req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", &qid);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
qid.type, qid.path, qid.version);
memmove(&fid->qid, &qid, sizeof(struct p9_qid));
p9_req_put(clnt, req);
return fid;
error:
if (fid)
p9_fid_destroy(fid);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_attach);
struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
const unsigned char * const *wnames, int clone)
{
int err;
struct p9_client *clnt;
struct p9_fid *fid;
struct p9_qid *wqids;
struct p9_req_t *req;
u16 nwqids, count;
wqids = NULL;
clnt = oldfid->clnt;
if (clone) {
fid = p9_fid_create(clnt);
if (!fid) {
err = -ENOMEM;
goto error;
}
fid->uid = oldfid->uid;
} else {
fid = oldfid;
}
p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
nwname, wnames);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "R", &nwqids, &wqids);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
goto clunk_fid;
}
p9_req_put(clnt, req);
p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
if (nwqids != nwname) {
err = -ENOENT;
goto clunk_fid;
}
for (count = 0; count < nwqids; count++)
p9_debug(P9_DEBUG_9P, "<<< [%d] %x.%llx.%x\n",
count, wqids[count].type,
wqids[count].path,
wqids[count].version);
if (nwname)
memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
else
memmove(&fid->qid, &oldfid->qid, sizeof(struct p9_qid));
kfree(wqids);
return fid;
clunk_fid:
kfree(wqids);
p9_fid_put(fid);
fid = NULL;
error:
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_client *clnt;
struct p9_req_t *req;
struct p9_qid qid;
int iounit;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
if (fid->mode != -1)
return -EINVAL;
if (p9_is_proto_dotl(clnt))
req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode & P9L_MODE_MASK);
else
req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode & P9L_MODE_MASK);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", &qid, &iounit);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto free_and_error;
}
p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN", qid.type,
qid.path, qid.version, iounit);
memmove(&fid->qid, &qid, sizeof(struct p9_qid));
fid->mode = mode;
fid->iounit = iounit;
free_and_error:
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_open);
int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags,
u32 mode, kgid_t gid, struct p9_qid *qid)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
int iounit;
p9_debug(P9_DEBUG_9P,
">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
ofid->fid, name, flags, mode,
from_kgid(&init_user_ns, gid));
clnt = ofid->clnt;
if (ofid->mode != -1)
return -EINVAL;
req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
mode & P9L_MODE_MASK, gid);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", qid, &iounit);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto free_and_error;
}
p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
qid->type, qid->path, qid->version, iounit);
memmove(&ofid->qid, qid, sizeof(struct p9_qid));
ofid->mode = flags;
ofid->iounit = iounit;
free_and_error:
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_create_dotl);
int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
char *extension)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
struct p9_qid qid;
int iounit;
p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
fid->fid, name, perm, mode);
clnt = fid->clnt;
if (fid->mode != -1)
return -EINVAL;
req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
mode & P9L_MODE_MASK, extension);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", &qid, &iounit);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto free_and_error;
}
p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
qid.type, qid.path, qid.version, iounit);
memmove(&fid->qid, &qid, sizeof(struct p9_qid));
fid->mode = mode;
fid->iounit = iounit;
free_and_error:
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_fcreate);
int p9_client_symlink(struct p9_fid *dfid, const char *name,
const char *symtgt, kgid_t gid, struct p9_qid *qid)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s symtgt %s\n",
dfid->fid, name, symtgt);
clnt = dfid->clnt;
req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
gid);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto free_and_error;
}
p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
qid->type, qid->path, qid->version);
free_and_error:
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_symlink);
int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, const char *newname)
{
struct p9_client *clnt;
struct p9_req_t *req;
p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
dfid->fid, oldfid->fid, newname);
clnt = dfid->clnt;
req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
newname);
if (IS_ERR(req))
return PTR_ERR(req);
p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
p9_req_put(clnt, req);
return 0;
}
EXPORT_SYMBOL(p9_client_link);
int p9_client_fsync(struct p9_fid *fid, int datasync)
{
int err = 0;
struct p9_client *clnt;
struct p9_req_t *req;
p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
fid->fid, datasync);
clnt = fid->clnt;
req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_fsync);
int p9_client_clunk(struct p9_fid *fid)
{
int err = 0;
struct p9_client *clnt;
struct p9_req_t *req;
int retries = 0;
again:
p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n",
fid->fid, retries);
clnt = fid->clnt;
req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
p9_req_put(clnt, req);
error:
/* Fid is not valid even after a failed clunk
* If interrupted, retry once then give up and
* leak fid until umount.
*/
if (err == -ERESTARTSYS) {
if (retries++ == 0)
goto again;
} else {
p9_fid_destroy(fid);
}
return err;
}
EXPORT_SYMBOL(p9_client_clunk);
int p9_client_remove(struct p9_fid *fid)
{
int err = 0;
struct p9_client *clnt;
struct p9_req_t *req;
p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
clnt = fid->clnt;
req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
p9_req_put(clnt, req);
error:
if (err == -ERESTARTSYS)
p9_fid_put(fid);
else
p9_fid_destroy(fid);
return err;
}
EXPORT_SYMBOL(p9_client_remove);
int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
{
int err = 0;
struct p9_req_t *req;
struct p9_client *clnt;
p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
dfid->fid, name, flags);
clnt = dfid->clnt;
req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_unlinkat);
int
p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
{
int total = 0;
*err = 0;
while (iov_iter_count(to)) {
int count;
count = p9_client_read_once(fid, offset, to, err);
if (!count || *err)
break;
offset += count;
total += count;
}
return total;
}
EXPORT_SYMBOL(p9_client_read);
int
p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to,
int *err)
{
struct p9_client *clnt = fid->clnt;
struct p9_req_t *req;
int count = iov_iter_count(to);
int rsize, received, non_zc = 0;
char *dataptr;
*err = 0;
p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %zu\n",
fid->fid, offset, iov_iter_count(to));
rsize = fid->iounit;
if (!rsize || rsize > clnt->msize - P9_IOHDRSZ)
rsize = clnt->msize - P9_IOHDRSZ;
if (count < rsize)
rsize = count;
/* Don't bother zerocopy for small IO (< 1024) */
if (clnt->trans_mod->zc_request && rsize > 1024) {
/* response header len is 11
* PDU Header(7) + IO Size (4)
*/
req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
0, 11, "dqd", fid->fid,
offset, rsize);
} else {
non_zc = 1;
req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
rsize);
}
if (IS_ERR(req)) {
*err = PTR_ERR(req);
if (!non_zc)
iov_iter_revert(to, count - iov_iter_count(to));
return 0;
}
*err = p9pdu_readf(&req->rc, clnt->proto_version,
"D", &received, &dataptr);
if (*err) {
if (!non_zc)
iov_iter_revert(to, count - iov_iter_count(to));
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
return 0;
}
if (rsize < received) {
pr_err("bogus RREAD count (%d > %d)\n", received, rsize);
received = rsize;
}
p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
if (non_zc) {
int n = copy_to_iter(dataptr, received, to);
if (n != received) {
*err = -EFAULT;
p9_req_put(clnt, req);
return n;
}
} else {
iov_iter_revert(to, count - received - iov_iter_count(to));
}
p9_req_put(clnt, req);
return received;
}
EXPORT_SYMBOL(p9_client_read_once);
int
p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
{
struct p9_client *clnt = fid->clnt;
struct p9_req_t *req;
int total = 0;
*err = 0;
p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
fid->fid, offset, iov_iter_count(from));
while (iov_iter_count(from)) {
int count = iov_iter_count(from);
int rsize = fid->iounit;
int written;
if (!rsize || rsize > clnt->msize - P9_IOHDRSZ)
rsize = clnt->msize - P9_IOHDRSZ;
if (count < rsize)
rsize = count;
/* Don't bother zerocopy for small IO (< 1024) */
if (clnt->trans_mod->zc_request && rsize > 1024) {
req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
rsize, P9_ZC_HDR_SZ, "dqd",
fid->fid, offset, rsize);
} else {
req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
offset, rsize, from);
}
if (IS_ERR(req)) {
iov_iter_revert(from, count - iov_iter_count(from));
*err = PTR_ERR(req);
break;
}
*err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &written);
if (*err) {
iov_iter_revert(from, count - iov_iter_count(from));
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
break;
}
if (rsize < written) {
pr_err("bogus RWRITE count (%d > %d)\n", written, rsize);
written = rsize;
}
p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
p9_req_put(clnt, req);
iov_iter_revert(from, count - written - iov_iter_count(from));
total += written;
offset += written;
}
return total;
}
EXPORT_SYMBOL(p9_client_write);
struct p9_wstat *p9_client_stat(struct p9_fid *fid)
{
int err;
struct p9_client *clnt;
struct p9_wstat *ret;
struct p9_req_t *req;
u16 ignored;
p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
ret = kmalloc(sizeof(*ret), GFP_KERNEL);
if (!ret)
return ERR_PTR(-ENOMEM);
clnt = fid->clnt;
req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "wS", &ignored, ret);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
goto error;
}
p9_debug(P9_DEBUG_9P,
"<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
"<<< mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
"<<< name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
"<<< uid=%d gid=%d n_muid=%d\n",
ret->size, ret->type, ret->dev, ret->qid.type, ret->qid.path,
ret->qid.version, ret->mode,
ret->atime, ret->mtime, ret->length,
ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
from_kuid(&init_user_ns, ret->n_uid),
from_kgid(&init_user_ns, ret->n_gid),
from_kuid(&init_user_ns, ret->n_muid));
p9_req_put(clnt, req);
return ret;
error:
kfree(ret);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_stat);
struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
u64 request_mask)
{
int err;
struct p9_client *clnt;
struct p9_stat_dotl *ret;
struct p9_req_t *req;
p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
fid->fid, request_mask);
ret = kmalloc(sizeof(*ret), GFP_KERNEL);
if (!ret)
return ERR_PTR(-ENOMEM);
clnt = fid->clnt;
req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "A", ret);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RGETATTR st_result_mask=%lld\n"
"<<< qid=%x.%llx.%x\n"
"<<< st_mode=%8.8x st_nlink=%llu\n"
"<<< st_uid=%d st_gid=%d\n"
"<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
"<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
"<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
"<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
"<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
"<<< st_gen=%lld st_data_version=%lld\n",
ret->st_result_mask,
ret->qid.type, ret->qid.path, ret->qid.version,
ret->st_mode, ret->st_nlink,
from_kuid(&init_user_ns, ret->st_uid),
from_kgid(&init_user_ns, ret->st_gid),
ret->st_rdev, ret->st_size, ret->st_blksize, ret->st_blocks,
ret->st_atime_sec, ret->st_atime_nsec,
ret->st_mtime_sec, ret->st_mtime_nsec,
ret->st_ctime_sec, ret->st_ctime_nsec,
ret->st_btime_sec, ret->st_btime_nsec,
ret->st_gen, ret->st_data_version);
p9_req_put(clnt, req);
return ret;
error:
kfree(ret);
return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_getattr_dotl);
static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
{
int ret;
/* NOTE: size shouldn't include its own length */
/* size[2] type[2] dev[4] qid[13] */
/* mode[4] atime[4] mtime[4] length[8]*/
/* name[s] uid[s] gid[s] muid[s] */
ret = 2 + 4 + 13 + 4 + 4 + 4 + 8 + 2 + 2 + 2 + 2;
if (wst->name)
ret += strlen(wst->name);
if (wst->uid)
ret += strlen(wst->uid);
if (wst->gid)
ret += strlen(wst->gid);
if (wst->muid)
ret += strlen(wst->muid);
if (proto_version == p9_proto_2000u ||
proto_version == p9_proto_2000L) {
/* extension[s] n_uid[4] n_gid[4] n_muid[4] */
ret += 2 + 4 + 4 + 4;
if (wst->extension)
ret += strlen(wst->extension);
}
return ret;
}
int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
{
int err = 0;
struct p9_req_t *req;
struct p9_client *clnt;
clnt = fid->clnt;
wst->size = p9_client_statsize(wst, clnt->proto_version);
p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n",
fid->fid);
p9_debug(P9_DEBUG_9P,
" sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
" mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
" name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
" uid=%d gid=%d n_muid=%d\n",
wst->size, wst->type, wst->dev, wst->qid.type,
wst->qid.path, wst->qid.version,
wst->mode, wst->atime, wst->mtime, wst->length,
wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
from_kuid(&init_user_ns, wst->n_uid),
from_kgid(&init_user_ns, wst->n_gid),
from_kuid(&init_user_ns, wst->n_muid));
req = p9_client_rpc(clnt, P9_TWSTAT, "dwS",
fid->fid, wst->size + 2, wst);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_wstat);
int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
{
int err = 0;
struct p9_req_t *req;
struct p9_client *clnt;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
p9_debug(P9_DEBUG_9P, " valid=%x mode=%x uid=%d gid=%d size=%lld\n",
p9attr->valid, p9attr->mode,
from_kuid(&init_user_ns, p9attr->uid),
from_kgid(&init_user_ns, p9attr->gid),
p9attr->size);
p9_debug(P9_DEBUG_9P, " atime_sec=%lld atime_nsec=%lld\n",
p9attr->atime_sec, p9attr->atime_nsec);
p9_debug(P9_DEBUG_9P, " mtime_sec=%lld mtime_nsec=%lld\n",
p9attr->mtime_sec, p9attr->mtime_nsec);
req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_setattr);
int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
{
int err;
struct p9_req_t *req;
struct p9_client *clnt;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
&sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
&sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
goto error;
}
p9_debug(P9_DEBUG_9P,
"<<< RSTATFS fid %d type 0x%x bsize %u blocks %llu bfree %llu bavail %llu files %llu ffree %llu fsid %llu namelen %u\n",
fid->fid, sb->type, sb->bsize, sb->blocks, sb->bfree,
sb->bavail, sb->files, sb->ffree, sb->fsid, sb->namelen);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_statfs);
int p9_client_rename(struct p9_fid *fid,
struct p9_fid *newdirfid, const char *name)
{
int err = 0;
struct p9_req_t *req;
struct p9_client *clnt;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
fid->fid, newdirfid->fid, name);
req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
newdirfid->fid, name);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_rename);
int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
struct p9_fid *newdirfid, const char *new_name)
{
int err = 0;
struct p9_req_t *req;
struct p9_client *clnt;
clnt = olddirfid->clnt;
p9_debug(P9_DEBUG_9P,
">>> TRENAMEAT olddirfid %d old name %s newdirfid %d new name %s\n",
olddirfid->fid, old_name, newdirfid->fid, new_name);
req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
old_name, newdirfid->fid, new_name);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
newdirfid->fid, new_name);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_renameat);
/* An xattrwalk without @attr_name gives the fid for the lisxattr namespace
*/
struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
const char *attr_name, u64 *attr_size)
{
int err;
struct p9_req_t *req;
struct p9_client *clnt;
struct p9_fid *attr_fid;
clnt = file_fid->clnt;
attr_fid = p9_fid_create(clnt);
if (!attr_fid) {
err = -ENOMEM;
goto error;
}
p9_debug(P9_DEBUG_9P,
">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
file_fid->fid, attr_fid->fid, attr_name);
req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
file_fid->fid, attr_fid->fid, attr_name);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "q", attr_size);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
p9_req_put(clnt, req);
goto clunk_fid;
}
p9_req_put(clnt, req);
p9_debug(P9_DEBUG_9P, "<<< RXATTRWALK fid %d size %llu\n",
attr_fid->fid, *attr_size);
return attr_fid;
clunk_fid:
p9_fid_put(attr_fid);
attr_fid = NULL;
error:
if (attr_fid && attr_fid != file_fid)
p9_fid_destroy(attr_fid);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
u64 attr_size, int flags)
{
int err = 0;
struct p9_req_t *req;
struct p9_client *clnt;
p9_debug(P9_DEBUG_9P,
">>> TXATTRCREATE fid %d name %s size %llu flag %d\n",
fid->fid, name, attr_size, flags);
clnt = fid->clnt;
req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
fid->fid, name, attr_size, flags);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
{
int err, rsize, non_zc = 0;
struct p9_client *clnt;
struct p9_req_t *req;
char *dataptr;
struct kvec kv = {.iov_base = data, .iov_len = count};
struct iov_iter to;
iov_iter_kvec(&to, ITER_DEST, &kv, 1, count);
p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
fid->fid, offset, count);
clnt = fid->clnt;
rsize = fid->iounit;
if (!rsize || rsize > clnt->msize - P9_READDIRHDRSZ)
rsize = clnt->msize - P9_READDIRHDRSZ;
if (count < rsize)
rsize = count;
/* Don't bother zerocopy for small IO (< 1024) */
if (clnt->trans_mod->zc_request && rsize > 1024) {
/* response header len is 11
* PDU Header(7) + IO Size (4)
*/
req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
11, "dqd", fid->fid, offset, rsize);
} else {
non_zc = 1;
req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
offset, rsize);
}
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(&req->rc, clnt->proto_version, "D", &count, &dataptr);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto free_and_error;
}
if (rsize < count) {
pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize);
count = rsize;
}
p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
if (non_zc)
memmove(data, dataptr, count);
p9_req_put(clnt, req);
return count;
free_and_error:
p9_req_put(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_readdir);
int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode,
dev_t rdev, kgid_t gid, struct p9_qid *qid)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P,
">>> TMKNOD fid %d name %s mode %d major %d minor %d\n",
fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
MAJOR(rdev), MINOR(rdev), gid);
if (IS_ERR(req))
return PTR_ERR(req);
err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n",
qid->type, qid->path, qid->version);
error:
p9_req_put(clnt, req);
return err;
}
EXPORT_SYMBOL(p9_client_mknod_dotl);
int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
kgid_t gid, struct p9_qid *qid)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
fid->fid, name, mode, from_kgid(&init_user_ns, gid));
req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg",
fid->fid, name, mode, gid);
if (IS_ERR(req))
return PTR_ERR(req);
err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
qid->path, qid->version);
error:
p9_req_put(clnt, req);
return err;
}
EXPORT_SYMBOL(p9_client_mkdir_dotl);
int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P,
">>> TLOCK fid %d type %i flags %d start %lld length %lld proc_id %d client_id %s\n",
fid->fid, flock->type, flock->flags, flock->start,
flock->length, flock->proc_id, flock->client_id);
req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
flock->flags, flock->start, flock->length,
flock->proc_id, flock->client_id);
if (IS_ERR(req))
return PTR_ERR(req);
err = p9pdu_readf(&req->rc, clnt->proto_version, "b", status);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
error:
p9_req_put(clnt, req);
return err;
}
EXPORT_SYMBOL(p9_client_lock_dotl);
int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P,
">>> TGETLOCK fid %d, type %i start %lld length %lld proc_id %d client_id %s\n",
fid->fid, glock->type, glock->start, glock->length,
glock->proc_id, glock->client_id);
req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,
glock->type, glock->start, glock->length,
glock->proc_id, glock->client_id);
if (IS_ERR(req))
return PTR_ERR(req);
err = p9pdu_readf(&req->rc, clnt->proto_version, "bqqds", &glock->type,
&glock->start, &glock->length, &glock->proc_id,
&glock->client_id);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto error;
}
p9_debug(P9_DEBUG_9P,
"<<< RGETLOCK type %i start %lld length %lld proc_id %d client_id %s\n",
glock->type, glock->start, glock->length,
glock->proc_id, glock->client_id);
error:
p9_req_put(clnt, req);
return err;
}
EXPORT_SYMBOL(p9_client_getlock_dotl);
int p9_client_readlink(struct p9_fid *fid, char **target)
{
int err;
struct p9_client *clnt;
struct p9_req_t *req;
clnt = fid->clnt;
p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
if (IS_ERR(req))
return PTR_ERR(req);
err = p9pdu_readf(&req->rc, clnt->proto_version, "s", target);
if (err) {
trace_9p_protocol_dump(clnt, &req->rc);
goto error;
}
p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
error:
p9_req_put(clnt, req);
return err;
}
EXPORT_SYMBOL(p9_client_readlink);
int __init p9_client_init(void)
{
p9_req_cache = KMEM_CACHE(p9_req_t, SLAB_TYPESAFE_BY_RCU);
return p9_req_cache ? 0 : -ENOMEM;
}
void __exit p9_client_exit(void)
{
kmem_cache_destroy(p9_req_cache);
}
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