/* * linux/fs/9p/trans_fd.c * * Fd transport layer. Includes deprecated socket layer. * * Copyright (C) 2006 by Russ Cox * Copyright (C) 2004-2005 by Latchesar Ionkov * Copyright (C) 2004-2008 by Eric Van Hensbergen * Copyright (C) 1997-2002 by Ron Minnich * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define P9_PORT 564 #define MAX_SOCK_BUF (64*1024) #define ERREQFLUSH 1 #define MAXPOLLWADDR 2 /** * struct p9_fd_opts - per-transport options * @rfd: file descriptor for reading (trans=fd) * @wfd: file descriptor for writing (trans=fd) * @port: port to connect to (trans=tcp) * */ struct p9_fd_opts { int rfd; int wfd; u16 port; }; /** * struct p9_trans_fd - transport state * @rd: reference to file to read from * @wr: reference of file to write to * @conn: connection state reference * */ struct p9_trans_fd { struct file *rd; struct file *wr; struct p9_conn *conn; }; /* * Option Parsing (code inspired by NFS code) * - a little lazy - parse all fd-transport options */ enum { /* Options that take integer arguments */ Opt_port, Opt_rfdno, Opt_wfdno, Opt_err, }; static const match_table_t tokens = { {Opt_port, "port=%u"}, {Opt_rfdno, "rfdno=%u"}, {Opt_wfdno, "wfdno=%u"}, {Opt_err, NULL}, }; enum { Rworksched = 1, /* read work scheduled or running */ Rpending = 2, /* can read */ Wworksched = 4, /* write work scheduled or running */ Wpending = 8, /* can write */ }; enum { None, Flushing, Flushed, }; /** * struct p9_req - fd mux encoding of an rpc transaction * @lock: protects req_list * @tag: numeric tag for rpc transaction * @tcall: request &p9_fcall structure * @rcall: response &p9_fcall structure * @err: error state * @flush: flag to indicate RPC has been flushed * @req_list: list link for higher level objects to chain requests * @m: connection this request was issued on * @wqueue: wait queue that client is blocked on for this rpc * */ struct p9_req { spinlock_t lock; int tag; struct p9_fcall *tcall; struct p9_fcall *rcall; int err; int flush; struct list_head req_list; struct p9_conn *m; wait_queue_head_t wqueue; }; struct p9_poll_wait { struct p9_conn *conn; wait_queue_t wait; wait_queue_head_t *wait_addr; }; /** * struct p9_conn - fd mux connection state information * @lock: protects mux_list (?) * @mux_list: list link for mux to manage multiple connections (?) * @client: reference to client instance for this connection * @err: error state * @req_list: accounting for requests which have been sent * @unsent_req_list: accounting for requests that haven't been sent * @rcall: current response &p9_fcall structure * @rpos: read position in current frame * @rbuf: current read buffer * @wpos: write position for current frame * @wsize: amount of data to write for current frame * @wbuf: current write buffer * @poll_wait: array of wait_q's for various worker threads * @poll_waddr: ???? * @pt: poll state * @rq: current read work * @wq: current write work * @wsched: ???? * */ struct p9_conn { spinlock_t lock; /* protect lock structure */ struct list_head mux_list; struct p9_client *client; int err; struct list_head req_list; struct list_head unsent_req_list; struct p9_fcall *rcall; int rpos; char *rbuf; int wpos; int wsize; char *wbuf; struct list_head poll_pending_link; struct p9_poll_wait poll_wait[MAXPOLLWADDR]; poll_table pt; struct work_struct rq; struct work_struct wq; unsigned long wsched; }; static DEFINE_SPINLOCK(p9_poll_lock); static LIST_HEAD(p9_poll_pending_list); static struct workqueue_struct *p9_mux_wq; static struct task_struct *p9_poll_task; static void p9_mux_poll_stop(struct p9_conn *m) { unsigned long flags; int i; for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { struct p9_poll_wait *pwait = &m->poll_wait[i]; if (pwait->wait_addr) { remove_wait_queue(pwait->wait_addr, &pwait->wait); pwait->wait_addr = NULL; } } spin_lock_irqsave(&p9_poll_lock, flags); list_del_init(&m->poll_pending_link); spin_unlock_irqrestore(&p9_poll_lock, flags); } static void p9_mux_free_request(struct p9_conn *m, struct p9_req *req) { if (req->tag != P9_NOTAG && p9_idpool_check(req->tag, m->client->tagpool)) p9_idpool_put(req->tag, m->client->tagpool); kfree(req); } static void p9_conn_rpc_cb(struct p9_req *req); static void p9_mux_flush_cb(struct p9_req *freq) { int tag; struct p9_conn *m = freq->m; struct p9_req *req, *rreq, *rptr; P9_DPRINTK(P9_DEBUG_MUX, "mux %p tc %p rc %p err %d oldtag %d\n", m, freq->tcall, freq->rcall, freq->err, freq->tcall->params.tflush.oldtag); spin_lock(&m->lock); tag = freq->tcall->params.tflush.oldtag; req = NULL; list_for_each_entry_safe(rreq, rptr, &m->req_list, req_list) { if (rreq->tag == tag) { req = rreq; list_del(&req->req_list); break; } } spin_unlock(&m->lock); if (req) { spin_lock(&req->lock); req->flush = Flushed; spin_unlock(&req->lock); p9_conn_rpc_cb(req); } kfree(freq->tcall); kfree(freq->rcall); p9_mux_free_request(m, freq); } static void p9_conn_rpc_cb(struct p9_req *req) { P9_DPRINTK(P9_DEBUG_MUX, "req %p\n", req); if (req->tcall->id == P9_TFLUSH) { /* flush callback */ P9_DPRINTK(P9_DEBUG_MUX, "flush req %p\n", req); p9_mux_flush_cb(req); } else { /* normal wakeup path */ P9_DPRINTK(P9_DEBUG_MUX, "normal req %p\n", req); if (req->flush != None && !req->err) req->err = -ERESTARTSYS; wake_up(&req->wqueue); } } /** * p9_conn_cancel - cancel all pending requests with error * @m: mux data * @err: error code * */ void p9_conn_cancel(struct p9_conn *m, int err) { struct p9_req *req, *rtmp; LIST_HEAD(cancel_list); P9_DPRINTK(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); m->err = err; spin_lock(&m->lock); list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { list_move(&req->req_list, &cancel_list); } list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) { list_move(&req->req_list, &cancel_list); } spin_unlock(&m->lock); list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) { list_del(&req->req_list); if (!req->err) req->err = err; p9_conn_rpc_cb(req); } } static void process_request(struct p9_conn *m, struct p9_req *req) { int ecode; struct p9_str *ename; if (!req->err && req->rcall->id == P9_RERROR) { ecode = req->rcall->params.rerror.errno; ename = &req->rcall->params.rerror.error; P9_DPRINTK(P9_DEBUG_MUX, "Rerror %.*s\n", ename->len, ename->str); if (m->client->dotu) req->err = -ecode; if (!req->err) { req->err = p9_errstr2errno(ename->str, ename->len); /* string match failed */ if (!req->err) { PRINT_FCALL_ERROR("unknown error", req->rcall); req->err = -ESERVERFAULT; } } } else if (req->tcall && req->rcall->id != req->tcall->id + 1) { P9_DPRINTK(P9_DEBUG_ERROR, "fcall mismatch: expected %d, got %d\n", req->tcall->id + 1, req->rcall->id); if (!req->err) req->err = -EIO; } } static unsigned int p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt) { int ret, n; struct p9_trans_fd *ts = NULL; if (client && client->status == Connected) ts = client->trans; if (!ts) return -EREMOTEIO; if (!ts->rd->f_op || !ts->rd->f_op->poll) return -EIO; if (!ts->wr->f_op || !ts->wr->f_op->poll) return -EIO; ret = ts->rd->f_op->poll(ts->rd, pt); if (ret < 0) return ret; if (ts->rd != ts->wr) { n = ts->wr->f_op->poll(ts->wr, pt); if (n < 0) return n; ret = (ret & ~POLLOUT) | (n & ~POLLIN); } return ret; } /** * p9_fd_read- read from a fd * @client: client instance * @v: buffer to receive data into * @len: size of receive buffer * */ static int p9_fd_read(struct p9_client *client, void *v, int len) { int ret; struct p9_trans_fd *ts = NULL; if (client && client->status != Disconnected) ts = client->trans; if (!ts) return -EREMOTEIO; if (!(ts->rd->f_flags & O_NONBLOCK)) P9_DPRINTK(P9_DEBUG_ERROR, "blocking read ...\n"); ret = kernel_read(ts->rd, ts->rd->f_pos, v, len); if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) client->status = Disconnected; return ret; } /** * p9_read_work - called when there is some data to be read from a transport * @work: container of work to be done * */ static void p9_read_work(struct work_struct *work) { int n, err; struct p9_conn *m; struct p9_req *req, *rptr, *rreq; struct p9_fcall *rcall; char *rbuf; m = container_of(work, struct p9_conn, rq); if (m->err < 0) return; rcall = NULL; P9_DPRINTK(P9_DEBUG_MUX, "start mux %p pos %d\n", m, m->rpos); if (!m->rcall) { m->rcall = kmalloc(sizeof(struct p9_fcall) + m->client->msize, GFP_KERNEL); if (!m->rcall) { err = -ENOMEM; goto error; } m->rbuf = (char *)m->rcall + sizeof(struct p9_fcall); m->rpos = 0; } clear_bit(Rpending, &m->wsched); err = p9_fd_read(m->client, m->rbuf + m->rpos, m->client->msize - m->rpos); P9_DPRINTK(P9_DEBUG_MUX, "mux %p got %d bytes\n", m, err); if (err == -EAGAIN) { clear_bit(Rworksched, &m->wsched); return; } if (err <= 0) goto error; m->rpos += err; while (m->rpos > 4) { n = le32_to_cpu(*(__le32 *) m->rbuf); if (n >= m->client->msize) { P9_DPRINTK(P9_DEBUG_ERROR, "requested packet size too big: %d\n", n); err = -EIO; goto error; } if (m->rpos < n) break; err = p9_deserialize_fcall(m->rbuf, n, m->rcall, m->client->dotu); if (err < 0) goto error; #ifdef CONFIG_NET_9P_DEBUG if ((p9_debug_level&P9_DEBUG_FCALL) == P9_DEBUG_FCALL) { char buf[150]; p9_printfcall(buf, sizeof(buf), m->rcall, m->client->dotu); printk(KERN_NOTICE ">>> %p %s\n", m, buf); } #endif rcall = m->rcall; rbuf = m->rbuf; if (m->rpos > n) { m->rcall = kmalloc(sizeof(struct p9_fcall) + m->client->msize, GFP_KERNEL); if (!m->rcall) { err = -ENOMEM; goto error; } m->rbuf = (char *)m->rcall + sizeof(struct p9_fcall); memmove(m->rbuf, rbuf + n, m->rpos - n); m->rpos -= n; } else { m->rcall = NULL; m->rbuf = NULL; m->rpos = 0; } P9_DPRINTK(P9_DEBUG_MUX, "mux %p fcall id %d tag %d\n", m, rcall->id, rcall->tag); req = NULL; spin_lock(&m->lock); list_for_each_entry_safe(rreq, rptr, &m->req_list, req_list) { if (rreq->tag == rcall->tag) { req = rreq; if (req->flush != Flushing) list_del(&req->req_list); break; } } spin_unlock(&m->lock); if (req) { req->rcall = rcall; process_request(m, req); if (req->flush != Flushing) p9_conn_rpc_cb(req); } else { if (err >= 0 && rcall->id != P9_RFLUSH) P9_DPRINTK(P9_DEBUG_ERROR, "unexpected response mux %p id %d tag %d\n", m, rcall->id, rcall->tag); kfree(rcall); } } if (!list_empty(&m->req_list)) { if (test_and_clear_bit(Rpending, &m->wsched)) n = POLLIN; else n = p9_fd_poll(m->client, NULL); if (n & POLLIN) { P9_DPRINTK(P9_DEBUG_MUX, "schedule read work %p\n", m); queue_work(p9_mux_wq, &m->rq); } else clear_bit(Rworksched, &m->wsched); } else clear_bit(Rworksched, &m->wsched); return; error: p9_conn_cancel(m, err); clear_bit(Rworksched, &m->wsched); } /** * p9_fd_write - write to a socket * @client: client instance * @v: buffer to send data from * @len: size of send buffer * */ static int p9_fd_write(struct p9_client *client, void *v, int len) { int ret; mm_segment_t oldfs; struct p9_trans_fd *ts = NULL; if (client && client->status != Disconnected) ts = client->trans; if (!ts) return -EREMOTEIO; if (!(ts->wr->f_flags & O_NONBLOCK)) P9_DPRINTK(P9_DEBUG_ERROR, "blocking write ...\n"); oldfs = get_fs(); set_fs(get_ds()); /* The cast to a user pointer is valid due to the set_fs() */ ret = vfs_write(ts->wr, (void __user *)v, len, &ts->wr->f_pos); set_fs(oldfs); if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) client->status = Disconnected; return ret; } /** * p9_write_work - called when a transport can send some data * @work: container for work to be done * */ static void p9_write_work(struct work_struct *work) { int n, err; struct p9_conn *m; struct p9_req *req; m = container_of(work, struct p9_conn, wq); if (m->err < 0) { clear_bit(Wworksched, &m->wsched); return; } if (!m->wsize) { if (list_empty(&m->unsent_req_list)) { clear_bit(Wworksched, &m->wsched); return; } spin_lock(&m->lock); again: req = list_entry(m->unsent_req_list.next, struct p9_req, req_list); list_move_tail(&req->req_list, &m->req_list); if (req->err == ERREQFLUSH) goto again; m->wbuf = req->tcall->sdata; m->wsize = req->tcall->size; m->wpos = 0; spin_unlock(&m->lock); } P9_DPRINTK(P9_DEBUG_MUX, "mux %p pos %d size %d\n", m, m->wpos, m->wsize); clear_bit(Wpending, &m->wsched); err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos); P9_DPRINTK(P9_DEBUG_MUX, "mux %p sent %d bytes\n", m, err); if (err == -EAGAIN) { clear_bit(Wworksched, &m->wsched); return; } if (err < 0) goto error; else if (err == 0) { err = -EREMOTEIO; goto error; } m->wpos += err; if (m->wpos == m->wsize) m->wpos = m->wsize = 0; if (m->wsize == 0 && !list_empty(&m->unsent_req_list)) { if (test_and_clear_bit(Wpending, &m->wsched)) n = POLLOUT; else n = p9_fd_poll(m->client, NULL); if (n & POLLOUT) { P9_DPRINTK(P9_DEBUG_MUX, "schedule write work %p\n", m); queue_work(p9_mux_wq, &m->wq); } else clear_bit(Wworksched, &m->wsched); } else clear_bit(Wworksched, &m->wsched); return; error: p9_conn_cancel(m, err); clear_bit(Wworksched, &m->wsched); } static int p9_pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key) { struct p9_poll_wait *pwait = container_of(wait, struct p9_poll_wait, wait); struct p9_conn *m = pwait->conn; unsigned long flags; DECLARE_WAITQUEUE(dummy_wait, p9_poll_task); spin_lock_irqsave(&p9_poll_lock, flags); if (list_empty(&m->poll_pending_link)) list_add_tail(&m->poll_pending_link, &p9_poll_pending_list); spin_unlock_irqrestore(&p9_poll_lock, flags); /* perform the default wake up operation */ return default_wake_function(&dummy_wait, mode, sync, key); } /** * p9_pollwait - add poll task to the wait queue * @filp: file pointer being polled * @wait_address: wait_q to block on * @p: poll state * * called by files poll operation to add v9fs-poll task to files wait queue */ static void p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) { struct p9_conn *m = container_of(p, struct p9_conn, pt); struct p9_poll_wait *pwait = NULL; int i; for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { if (m->poll_wait[i].wait_addr == NULL) { pwait = &m->poll_wait[i]; break; } } if (!pwait) { P9_DPRINTK(P9_DEBUG_ERROR, "not enough wait_address slots\n"); return; } if (!wait_address) { P9_DPRINTK(P9_DEBUG_ERROR, "no wait_address\n"); pwait->wait_addr = ERR_PTR(-EIO); return; } pwait->conn = m; pwait->wait_addr = wait_address; init_waitqueue_func_entry(&pwait->wait, p9_pollwake); add_wait_queue(wait_address, &pwait->wait); } /** * p9_conn_create - allocate and initialize the per-session mux data * @client: client instance * * Note: Creates the polling task if this is the first session. */ static struct p9_conn *p9_conn_create(struct p9_client *client) { int i, n; struct p9_conn *m; P9_DPRINTK(P9_DEBUG_MUX, "client %p msize %d\n", client, client->msize); m = kzalloc(sizeof(struct p9_conn), GFP_KERNEL); if (!m) return ERR_PTR(-ENOMEM); spin_lock_init(&m->lock); INIT_LIST_HEAD(&m->mux_list); m->client = client; INIT_LIST_HEAD(&m->req_list); INIT_LIST_HEAD(&m->unsent_req_list); INIT_WORK(&m->rq, p9_read_work); INIT_WORK(&m->wq, p9_write_work); INIT_LIST_HEAD(&m->poll_pending_link); init_poll_funcptr(&m->pt, p9_pollwait); n = p9_fd_poll(client, &m->pt); if (n & POLLIN) { P9_DPRINTK(P9_DEBUG_MUX, "mux %p can read\n", m); set_bit(Rpending, &m->wsched); } if (n & POLLOUT) { P9_DPRINTK(P9_DEBUG_MUX, "mux %p can write\n", m); set_bit(Wpending, &m->wsched); } for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { if (IS_ERR(m->poll_wait[i].wait_addr)) { p9_mux_poll_stop(m); kfree(m); /* return the error code */ return (void *)m->poll_wait[i].wait_addr; } } return m; } /** * p9_poll_mux - polls a mux and schedules read or write works if necessary * @m: connection to poll * */ static void p9_poll_mux(struct p9_conn *m) { int n; if (m->err < 0) return; n = p9_fd_poll(m->client, NULL); if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) { P9_DPRINTK(P9_DEBUG_MUX, "error mux %p err %d\n", m, n); if (n >= 0) n = -ECONNRESET; p9_conn_cancel(m, n); } if (n & POLLIN) { set_bit(Rpending, &m->wsched); P9_DPRINTK(P9_DEBUG_MUX, "mux %p can read\n", m); if (!test_and_set_bit(Rworksched, &m->wsched)) { P9_DPRINTK(P9_DEBUG_MUX, "schedule read work %p\n", m); queue_work(p9_mux_wq, &m->rq); } } if (n & POLLOUT) { set_bit(Wpending, &m->wsched); P9_DPRINTK(P9_DEBUG_MUX, "mux %p can write\n", m); if ((m->wsize || !list_empty(&m->unsent_req_list)) && !test_and_set_bit(Wworksched, &m->wsched)) { P9_DPRINTK(P9_DEBUG_MUX, "schedule write work %p\n", m); queue_work(p9_mux_wq, &m->wq); } } } /** * p9_send_request - send 9P request * The function can sleep until the request is scheduled for sending. * The function can be interrupted. Return from the function is not * a guarantee that the request is sent successfully. Can return errors * that can be retrieved by PTR_ERR macros. * * @m: mux data * @tc: request to be sent * */ static struct p9_req *p9_send_request(struct p9_conn *m, struct p9_fcall *tc) { int n; struct p9_req *req; P9_DPRINTK(P9_DEBUG_MUX, "mux %p task %p tcall %p id %d\n", m, current, tc, tc->id); if (m->err < 0) return ERR_PTR(m->err); req = kmalloc(sizeof(struct p9_req), GFP_KERNEL); if (!req) return ERR_PTR(-ENOMEM); n = P9_NOTAG; if (tc->id != P9_TVERSION) { n = p9_idpool_get(m->client->tagpool); if (n < 0) { kfree(req); return ERR_PTR(-ENOMEM); } } p9_set_tag(tc, n); #ifdef CONFIG_NET_9P_DEBUG if ((p9_debug_level&P9_DEBUG_FCALL) == P9_DEBUG_FCALL) { char buf[150]; p9_printfcall(buf, sizeof(buf), tc, m->client->dotu); printk(KERN_NOTICE "<<< %p %s\n", m, buf); } #endif spin_lock_init(&req->lock); req->m = m; init_waitqueue_head(&req->wqueue); req->tag = n; req->tcall = tc; req->rcall = NULL; req->err = 0; req->flush = None; spin_lock(&m->lock); list_add_tail(&req->req_list, &m->unsent_req_list); spin_unlock(&m->lock); if (test_and_clear_bit(Wpending, &m->wsched)) n = POLLOUT; else n = p9_fd_poll(m->client, NULL); if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) queue_work(p9_mux_wq, &m->wq); return req; } static int p9_mux_flush_request(struct p9_conn *m, struct p9_req *req) { struct p9_fcall *fc; struct p9_req *rreq, *rptr; P9_DPRINTK(P9_DEBUG_MUX, "mux %p req %p tag %d\n", m, req, req->tag); /* if a response was received for a request, do nothing */ spin_lock(&req->lock); if (req->rcall || req->err) { spin_unlock(&req->lock); P9_DPRINTK(P9_DEBUG_MUX, "mux %p req %p response already received\n", m, req); return 0; } req->flush = Flushing; spin_unlock(&req->lock); spin_lock(&m->lock); /* if the request is not sent yet, just remove it from the list */ list_for_each_entry_safe(rreq, rptr, &m->unsent_req_list, req_list) { if (rreq->tag == req->tag) { P9_DPRINTK(P9_DEBUG_MUX, "mux %p req %p request is not sent yet\n", m, req); list_del(&rreq->req_list); req->flush = Flushed; spin_unlock(&m->lock); p9_conn_rpc_cb(req); return 0; } } spin_unlock(&m->lock); clear_thread_flag(TIF_SIGPENDING); fc = p9_create_tflush(req->tag); p9_send_request(m, fc); return 1; } /** * p9_fd_rpc- sends 9P request and waits until a response is available. * The function can be interrupted. * @client: client instance * @tc: request to be sent * @rc: pointer where a pointer to the response is stored * */ int p9_fd_rpc(struct p9_client *client, struct p9_fcall *tc, struct p9_fcall **rc) { struct p9_trans_fd *p = client->trans; struct p9_conn *m = p->conn; int err, sigpending; unsigned long flags; struct p9_req *req; if (rc) *rc = NULL; sigpending = 0; if (signal_pending(current)) { sigpending = 1; clear_thread_flag(TIF_SIGPENDING); } req = p9_send_request(m, tc); if (IS_ERR(req)) { err = PTR_ERR(req); P9_DPRINTK(P9_DEBUG_MUX, "error %d\n", err); return err; } err = wait_event_interruptible(req->wqueue, req->rcall != NULL || req->err < 0); if (req->err < 0) err = req->err; if (err == -ERESTARTSYS && client->status == Connected && m->err == 0) { if (p9_mux_flush_request(m, req)) { /* wait until we get response of the flush message */ do { clear_thread_flag(TIF_SIGPENDING); err = wait_event_interruptible(req->wqueue, req->rcall || req->err); } while (!req->rcall && !req->err && err == -ERESTARTSYS && client->status == Connected && !m->err); err = -ERESTARTSYS; } sigpending = 1; } if (sigpending) { spin_lock_irqsave(¤t->sighand->siglock, flags); recalc_sigpending(); spin_unlock_irqrestore(¤t->sighand->siglock, flags); } if (rc) *rc = req->rcall; else kfree(req->rcall); p9_mux_free_request(m, req); if (err > 0) err = -EIO; return err; } /** * parse_options - parse mount options into session structure * @options: options string passed from mount * @opts: transport-specific structure to parse options into * * Returns 0 upon success, -ERRNO upon failure */ static int parse_opts(char *params, struct p9_fd_opts *opts) { char *p; substring_t args[MAX_OPT_ARGS]; int option; char *options; int ret; opts->port = P9_PORT; opts->rfd = ~0; opts->wfd = ~0; if (!params) return 0; options = kstrdup(params, 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; int r; if (!*p) continue; token = match_token(p, tokens, args); 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_port: opts->port = option; break; case Opt_rfdno: opts->rfd = option; break; case Opt_wfdno: opts->wfd = option; break; default: continue; } } kfree(options); return 0; } static int p9_fd_open(struct p9_client *client, int rfd, int wfd) { struct p9_trans_fd *ts = kmalloc(sizeof(struct p9_trans_fd), GFP_KERNEL); if (!ts) return -ENOMEM; ts->rd = fget(rfd); ts->wr = fget(wfd); if (!ts->rd || !ts->wr) { if (ts->rd) fput(ts->rd); if (ts->wr) fput(ts->wr); kfree(ts); return -EIO; } client->trans = ts; client->status = Connected; return 0; } static int p9_socket_open(struct p9_client *client, struct socket *csocket) { int fd, ret; csocket->sk->sk_allocation = GFP_NOIO; fd = sock_map_fd(csocket, 0); if (fd < 0) { P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to map fd\n"); return fd; } ret = p9_fd_open(client, fd, fd); if (ret < 0) { P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to open fd\n"); sockfd_put(csocket); return ret; } ((struct p9_trans_fd *)client->trans)->rd->f_flags |= O_NONBLOCK; return 0; } /** * p9_mux_destroy - cancels all pending requests and frees mux resources * @m: mux to destroy * */ static void p9_conn_destroy(struct p9_conn *m) { P9_DPRINTK(P9_DEBUG_MUX, "mux %p prev %p next %p\n", m, m->mux_list.prev, m->mux_list.next); p9_mux_poll_stop(m); cancel_work_sync(&m->rq); cancel_work_sync(&m->wq); p9_conn_cancel(m, -ECONNRESET); m->client = NULL; kfree(m); } /** * p9_fd_close - shutdown file descriptor transport * @client: client instance * */ static void p9_fd_close(struct p9_client *client) { struct p9_trans_fd *ts; if (!client) return; ts = client->trans; if (!ts) return; client->status = Disconnected; p9_conn_destroy(ts->conn); if (ts->rd) fput(ts->rd); if (ts->wr) fput(ts->wr); kfree(ts); } /* * stolen from NFS - maybe should be made a generic function? */ static inline int valid_ipaddr4(const char *buf) { int rc, count, in[4]; rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); if (rc != 4) return -EINVAL; for (count = 0; count < 4; count++) { if (in[count] > 255) return -EINVAL; } return 0; } static int p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args) { int err; struct socket *csocket; struct sockaddr_in sin_server; struct p9_fd_opts opts; struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */ err = parse_opts(args, &opts); if (err < 0) return err; if (valid_ipaddr4(addr) < 0) return -EINVAL; csocket = NULL; sin_server.sin_family = AF_INET; sin_server.sin_addr.s_addr = in_aton(addr); sin_server.sin_port = htons(opts.port); sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket); if (!csocket) { P9_EPRINTK(KERN_ERR, "p9_trans_tcp: problem creating socket\n"); err = -EIO; goto error; } err = csocket->ops->connect(csocket, (struct sockaddr *)&sin_server, sizeof(struct sockaddr_in), 0); if (err < 0) { P9_EPRINTK(KERN_ERR, "p9_trans_tcp: problem connecting socket to %s\n", addr); goto error; } err = p9_socket_open(client, csocket); if (err < 0) goto error; p = (struct p9_trans_fd *) client->trans; p->conn = p9_conn_create(client); if (IS_ERR(p->conn)) { err = PTR_ERR(p->conn); p->conn = NULL; goto error; } return 0; error: if (csocket) sock_release(csocket); kfree(p); return err; } static int p9_fd_create_unix(struct p9_client *client, const char *addr, char *args) { int err; struct socket *csocket; struct sockaddr_un sun_server; struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */ csocket = NULL; if (strlen(addr) > UNIX_PATH_MAX) { P9_EPRINTK(KERN_ERR, "p9_trans_unix: address too long: %s\n", addr); err = -ENAMETOOLONG; goto error; } sun_server.sun_family = PF_UNIX; strcpy(sun_server.sun_path, addr); sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket); err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server, sizeof(struct sockaddr_un) - 1, 0); if (err < 0) { P9_EPRINTK(KERN_ERR, "p9_trans_unix: problem connecting socket: %s: %d\n", addr, err); goto error; } err = p9_socket_open(client, csocket); if (err < 0) goto error; p = (struct p9_trans_fd *) client->trans; p->conn = p9_conn_create(client); if (IS_ERR(p->conn)) { err = PTR_ERR(p->conn); p->conn = NULL; goto error; } return 0; error: if (csocket) sock_release(csocket); kfree(p); return err; } static int p9_fd_create(struct p9_client *client, const char *addr, char *args) { int err; struct p9_fd_opts opts; struct p9_trans_fd *p = NULL; /* this get allocated in p9_fd_open */ parse_opts(args, &opts); if (opts.rfd == ~0 || opts.wfd == ~0) { printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n"); return -ENOPROTOOPT; } err = p9_fd_open(client, opts.rfd, opts.wfd); if (err < 0) goto error; p = (struct p9_trans_fd *) client->trans; p->conn = p9_conn_create(client); if (IS_ERR(p->conn)) { err = PTR_ERR(p->conn); p->conn = NULL; goto error; } return 0; error: kfree(p); return err; } static struct p9_trans_module p9_tcp_trans = { .name = "tcp", .maxsize = MAX_SOCK_BUF, .def = 1, .create = p9_fd_create_tcp, .close = p9_fd_close, .rpc = p9_fd_rpc, .owner = THIS_MODULE, }; static struct p9_trans_module p9_unix_trans = { .name = "unix", .maxsize = MAX_SOCK_BUF, .def = 0, .create = p9_fd_create_unix, .close = p9_fd_close, .rpc = p9_fd_rpc, .owner = THIS_MODULE, }; static struct p9_trans_module p9_fd_trans = { .name = "fd", .maxsize = MAX_SOCK_BUF, .def = 0, .create = p9_fd_create, .close = p9_fd_close, .rpc = p9_fd_rpc, .owner = THIS_MODULE, }; /** * p9_poll_proc - poll worker thread * @a: thread state and arguments * * polls all v9fs transports for new events and queues the appropriate * work to the work queue * */ static int p9_poll_proc(void *a) { unsigned long flags; P9_DPRINTK(P9_DEBUG_MUX, "start %p\n", current); repeat: spin_lock_irqsave(&p9_poll_lock, flags); while (!list_empty(&p9_poll_pending_list)) { struct p9_conn *conn = list_first_entry(&p9_poll_pending_list, struct p9_conn, poll_pending_link); list_del_init(&conn->poll_pending_link); spin_unlock_irqrestore(&p9_poll_lock, flags); p9_poll_mux(conn); spin_lock_irqsave(&p9_poll_lock, flags); } spin_unlock_irqrestore(&p9_poll_lock, flags); set_current_state(TASK_INTERRUPTIBLE); if (list_empty(&p9_poll_pending_list)) { P9_DPRINTK(P9_DEBUG_MUX, "sleeping...\n"); schedule(); } __set_current_state(TASK_RUNNING); if (!kthread_should_stop()) goto repeat; P9_DPRINTK(P9_DEBUG_MUX, "finish\n"); return 0; } int p9_trans_fd_init(void) { p9_mux_wq = create_workqueue("v9fs"); if (!p9_mux_wq) { printk(KERN_WARNING "v9fs: mux: creating workqueue failed\n"); return -ENOMEM; } p9_poll_task = kthread_run(p9_poll_proc, NULL, "v9fs-poll"); if (IS_ERR(p9_poll_task)) { destroy_workqueue(p9_mux_wq); printk(KERN_WARNING "v9fs: mux: creating poll task failed\n"); return PTR_ERR(p9_poll_task); } v9fs_register_trans(&p9_tcp_trans); v9fs_register_trans(&p9_unix_trans); v9fs_register_trans(&p9_fd_trans); return 0; } void p9_trans_fd_exit(void) { kthread_stop(p9_poll_task); v9fs_unregister_trans(&p9_tcp_trans); v9fs_unregister_trans(&p9_unix_trans); v9fs_unregister_trans(&p9_fd_trans); destroy_workqueue(p9_mux_wq); }