diff options
Diffstat (limited to 'net/9p/trans_fd.c')
| -rw-r--r-- | net/9p/trans_fd.c | 1103 |
1 files changed, 1081 insertions, 22 deletions
diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c index 62332ed9da4..1aa9d517539 100644 --- a/net/9p/trans_fd.c +++ b/net/9p/trans_fd.c @@ -5,7 +5,7 @@ * * Copyright (C) 2006 by Russ Cox <rsc@swtch.com> * Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net> - * Copyright (C) 2004-2007 by Eric Van Hensbergen <ericvh@gmail.com> + * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com> * Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com> * * This program is free software; you can redistribute it and/or modify @@ -29,6 +29,7 @@ #include <linux/module.h> #include <linux/net.h> #include <linux/ipv6.h> +#include <linux/kthread.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/un.h> @@ -42,7 +43,9 @@ #define P9_PORT 564 #define MAX_SOCK_BUF (64*1024) - +#define ERREQFLUSH 1 +#define SCHED_TIMEOUT 10 +#define MAXPOLLWADDR 2 struct p9_fd_opts { int rfd; @@ -53,6 +56,7 @@ struct p9_fd_opts { struct p9_trans_fd { struct file *rd; struct file *wr; + struct p9_conn *conn; }; /* @@ -72,6 +76,1028 @@ static match_table_t tokens = { {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; + +typedef void (*p9_conn_req_callback)(struct p9_req *req, void *a); +struct p9_req { + spinlock_t lock; /* protect request structure */ + int tag; + struct p9_fcall *tcall; + struct p9_fcall *rcall; + int err; + p9_conn_req_callback cb; + void *cba; + int flush; + struct list_head req_list; +}; + +struct p9_mux_poll_task; + +struct p9_conn { + spinlock_t lock; /* protect lock structure */ + struct list_head mux_list; + struct p9_mux_poll_task *poll_task; + int msize; + unsigned char extended; + struct p9_trans *trans; + struct p9_idpool *tagpool; + int err; + wait_queue_head_t equeue; + 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; + wait_queue_t poll_wait[MAXPOLLWADDR]; + wait_queue_head_t *poll_waddr[MAXPOLLWADDR]; + poll_table pt; + struct work_struct rq; + struct work_struct wq; + unsigned long wsched; +}; + +struct p9_mux_poll_task { + struct task_struct *task; + struct list_head mux_list; + int muxnum; +}; + +struct p9_mux_rpc { + struct p9_conn *m; + int err; + struct p9_fcall *tcall; + struct p9_fcall *rcall; + wait_queue_head_t wqueue; +}; + +static int p9_poll_proc(void *); +static void p9_read_work(struct work_struct *work); +static void p9_write_work(struct work_struct *work); +static void p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, + poll_table *p); +static int p9_fd_write(struct p9_trans *trans, void *v, int len); +static int p9_fd_read(struct p9_trans *trans, void *v, int len); + +static DEFINE_MUTEX(p9_mux_task_lock); +static struct workqueue_struct *p9_mux_wq; + +static int p9_mux_num; +static int p9_mux_poll_task_num; +static struct p9_mux_poll_task p9_mux_poll_tasks[100]; + +static void p9_conn_destroy(struct p9_conn *); +static unsigned int p9_fd_poll(struct p9_trans *trans, + struct poll_table_struct *pt); + +#ifdef P9_NONBLOCK +static int p9_conn_rpcnb(struct p9_conn *m, struct p9_fcall *tc, + p9_conn_req_callback cb, void *a); +#endif /* P9_NONBLOCK */ + +static void p9_conn_cancel(struct p9_conn *m, int err); + +static int p9_mux_global_init(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(p9_mux_poll_tasks); i++) + p9_mux_poll_tasks[i].task = NULL; + + p9_mux_wq = create_workqueue("v9fs"); + if (!p9_mux_wq) { + printk(KERN_WARNING "v9fs: mux: creating workqueue failed\n"); + return -ENOMEM; + } + + return 0; +} + +static u16 p9_mux_get_tag(struct p9_conn *m) +{ + int tag; + + tag = p9_idpool_get(m->tagpool); + if (tag < 0) + return P9_NOTAG; + else + return (u16) tag; +} + +static void p9_mux_put_tag(struct p9_conn *m, u16 tag) +{ + if (tag != P9_NOTAG && p9_idpool_check(tag, m->tagpool)) + p9_idpool_put(tag, m->tagpool); +} + +/** + * p9_mux_calc_poll_procs - calculates the number of polling procs + * based on the number of mounted v9fs filesystems. + * + * The current implementation returns sqrt of the number of mounts. + */ +static int p9_mux_calc_poll_procs(int muxnum) +{ + int n; + + if (p9_mux_poll_task_num) + n = muxnum / p9_mux_poll_task_num + + (muxnum % p9_mux_poll_task_num ? 1 : 0); + else + n = 1; + + if (n > ARRAY_SIZE(p9_mux_poll_tasks)) + n = ARRAY_SIZE(p9_mux_poll_tasks); + + return n; +} + +static int p9_mux_poll_start(struct p9_conn *m) +{ + int i, n; + struct p9_mux_poll_task *vpt, *vptlast; + struct task_struct *pproc; + + P9_DPRINTK(P9_DEBUG_MUX, "mux %p muxnum %d procnum %d\n", m, p9_mux_num, + p9_mux_poll_task_num); + mutex_lock(&p9_mux_task_lock); + + n = p9_mux_calc_poll_procs(p9_mux_num + 1); + if (n > p9_mux_poll_task_num) { + for (i = 0; i < ARRAY_SIZE(p9_mux_poll_tasks); i++) { + if (p9_mux_poll_tasks[i].task == NULL) { + vpt = &p9_mux_poll_tasks[i]; + P9_DPRINTK(P9_DEBUG_MUX, "create proc %p\n", + vpt); + pproc = kthread_create(p9_poll_proc, vpt, + "v9fs-poll"); + + if (!IS_ERR(pproc)) { + vpt->task = pproc; + INIT_LIST_HEAD(&vpt->mux_list); + vpt->muxnum = 0; + p9_mux_poll_task_num++; + wake_up_process(vpt->task); + } + break; + } + } + + if (i >= ARRAY_SIZE(p9_mux_poll_tasks)) + P9_DPRINTK(P9_DEBUG_ERROR, + "warning: no free poll slots\n"); + } + + n = (p9_mux_num + 1) / p9_mux_poll_task_num + + ((p9_mux_num + 1) % p9_mux_poll_task_num ? 1 : 0); + + vptlast = NULL; + for (i = 0; i < ARRAY_SIZE(p9_mux_poll_tasks); i++) { + vpt = &p9_mux_poll_tasks[i]; + if (vpt->task != NULL) { + vptlast = vpt; + if (vpt->muxnum < n) { + P9_DPRINTK(P9_DEBUG_MUX, "put in proc %d\n", i); + list_add(&m->mux_list, &vpt->mux_list); + vpt->muxnum++; + m->poll_task = vpt; + memset(&m->poll_waddr, 0, + sizeof(m->poll_waddr)); + init_poll_funcptr(&m->pt, p9_pollwait); + break; + } + } + } + + if (i >= ARRAY_SIZE(p9_mux_poll_tasks)) { + if (vptlast == NULL) { + mutex_unlock(&p9_mux_task_lock); + return -ENOMEM; + } + + P9_DPRINTK(P9_DEBUG_MUX, "put in proc %d\n", i); + list_add(&m->mux_list, &vptlast->mux_list); + vptlast->muxnum++; + m->poll_task = vptlast; + memset(&m->poll_waddr, 0, sizeof(m->poll_waddr)); + init_poll_funcptr(&m->pt, p9_pollwait); + } + + p9_mux_num++; + mutex_unlock(&p9_mux_task_lock); + + return 0; +} + +static void p9_mux_poll_stop(struct p9_conn *m) +{ + int i; + struct p9_mux_poll_task *vpt; + + mutex_lock(&p9_mux_task_lock); + vpt = m->poll_task; + list_del(&m->mux_list); + for (i = 0; i < ARRAY_SIZE(m->poll_waddr); i++) { + if (m->poll_waddr[i] != NULL) { + remove_wait_queue(m->poll_waddr[i], &m->poll_wait[i]); + m->poll_waddr[i] = NULL; + } + } + vpt->muxnum--; + if (!vpt->muxnum) { + P9_DPRINTK(P9_DEBUG_MUX, "destroy proc %p\n", vpt); + kthread_stop(vpt->task); + vpt->task = NULL; + p9_mux_poll_task_num--; + } + p9_mux_num--; + mutex_unlock(&p9_mux_task_lock); +} + +/** + * p9_conn_create - allocate and initialize the per-session mux data + * Creates the polling task if this is the first session. + * + * @trans - transport structure + * @msize - maximum message size + * @extended - extended flag + */ +static struct p9_conn *p9_conn_create(struct p9_trans *trans) +{ + int i, n; + struct p9_conn *m, *mtmp; + + P9_DPRINTK(P9_DEBUG_MUX, "transport %p msize %d\n", trans, + trans->msize); + m = kmalloc(sizeof(struct p9_conn), GFP_KERNEL); + if (!m) + return ERR_PTR(-ENOMEM); + + spin_lock_init(&m->lock); + INIT_LIST_HEAD(&m->mux_list); + m->msize = trans->msize; + m->extended = trans->extended; + m->trans = trans; + m->tagpool = p9_idpool_create(); + if (IS_ERR(m->tagpool)) { + mtmp = ERR_PTR(-ENOMEM); + kfree(m); + return mtmp; + } + + m->err = 0; + init_waitqueue_head(&m->equeue); + INIT_LIST_HEAD(&m->req_list); + INIT_LIST_HEAD(&m->unsent_req_list); + m->rcall = NULL; + m->rpos = 0; + m->rbuf = NULL; + m->wpos = m->wsize = 0; + m->wbuf = NULL; + INIT_WORK(&m->rq, p9_read_work); + INIT_WORK(&m->wq, p9_write_work); + m->wsched = 0; + memset(&m->poll_waddr, 0, sizeof(m->poll_waddr)); + m->poll_task = NULL; + n = p9_mux_poll_start(m); + if (n) { + kfree(m); + return ERR_PTR(n); + } + + n = p9_fd_poll(trans, &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_waddr); i++) { + if (IS_ERR(m->poll_waddr[i])) { + p9_mux_poll_stop(m); + mtmp = (void *)m->poll_waddr; /* the error code */ + kfree(m); + m = mtmp; + break; + } + } + + return m; +} + +/** + * p9_mux_destroy - cancels all pending requests and frees mux resources + */ +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_conn_cancel(m, -ECONNRESET); + + if (!list_empty(&m->req_list)) { + /* wait until all processes waiting on this session exit */ + P9_DPRINTK(P9_DEBUG_MUX, + "mux %p waiting for empty request queue\n", m); + wait_event_timeout(m->equeue, (list_empty(&m->req_list)), 5000); + P9_DPRINTK(P9_DEBUG_MUX, "mux %p request queue empty: %d\n", m, + list_empty(&m->req_list)); + } + + p9_mux_poll_stop(m); + m->trans = NULL; + p9_idpool_destroy(m->tagpool); + kfree(m); +} + +/** + * p9_pollwait - 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) +{ + int i; + struct p9_conn *m; + + m = container_of(p, struct p9_conn, pt); + for (i = 0; i < ARRAY_SIZE(m->poll_waddr); i++) + if (m->poll_waddr[i] == NULL) + break; + + if (i >= ARRAY_SIZE(m->poll_waddr)) { + P9_DPRINTK(P9_DEBUG_ERROR, "not enough wait_address slots\n"); + return; + } + + m->poll_waddr[i] = wait_address; + + if (!wait_address) { + P9_DPRINTK(P9_DEBUG_ERROR, "no wait_address\n"); + m->poll_waddr[i] = ERR_PTR(-EIO); + return; + } + + init_waitqueue_entry(&m->poll_wait[i], m->poll_task->task); + add_wait_queue(wait_address, &m->poll_wait[i]); +} + +/** + * p9_poll_mux - polls a mux and schedules read or write works if necessary + */ +static void p9_poll_mux(struct p9_conn *m) +{ + int n; + + if (m->err < 0) + return; + + n = p9_fd_poll(m->trans, 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_poll_proc - polls all v9fs transports for new events and queues + * the appropriate work to the work queue + */ +static int p9_poll_proc(void *a) +{ + struct p9_conn *m, *mtmp; + struct p9_mux_poll_task *vpt; + + vpt = a; + P9_DPRINTK(P9_DEBUG_MUX, "start %p %p\n", current, vpt); + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + + list_for_each_entry_safe(m, mtmp, &vpt->mux_list, mux_list) { + p9_poll_mux(m); + } + + P9_DPRINTK(P9_DEBUG_MUX, "sleeping...\n"); + schedule_timeout(SCHED_TIMEOUT * HZ); + } + + __set_current_state(TASK_RUNNING); + P9_DPRINTK(P9_DEBUG_MUX, "finish\n"); + return 0; +} + +/** + * p9_write_work - called when a transport can send some data + */ +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->trans, 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->trans, 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 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->extended) + 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; + } +} + +/** + * p9_read_work - called when there is some data to be read from a transport + */ +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->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->trans, m->rbuf + m->rpos, m->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->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->extended); + 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->extended); + 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->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) { + if (req->cb) + (*req->cb) (req, req->cba); + else + kfree(req->rcall); + + wake_up(&m->equeue); + } + } 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->trans, 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_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 + * @cb: callback function to call when response is received + * @cba: parameter to pass to the callback function + */ +static struct p9_req *p9_send_request(struct p9_conn *m, + struct p9_fcall *tc, + p9_conn_req_callback cb, void *cba) +{ + 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); + + if (tc->id == P9_TVERSION) + n = P9_NOTAG; + else + n = p9_mux_get_tag(m); + + if (n < 0) + 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->extended); + printk(KERN_NOTICE "<<< %p %s\n", m, buf); + } +#endif + + spin_lock_init(&req->lock); + req->tag = n; + req->tcall = tc; + req->rcall = NULL; + req->err = 0; + req->cb = cb; + req->cba = cba; + 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->trans, NULL); + + if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) + queue_work(p9_mux_wq, &m->wq); + + return req; +} + +static void p9_mux_free_request(struct p9_conn *m, struct p9_req *req) +{ + p9_mux_put_tag(m, req->tag); + kfree(req); +} + +static void p9_mux_flush_cb(struct p9_req *freq, void *a) +{ + p9_conn_req_callback cb; + int tag; + struct p9_conn *m; + struct p9_req *req, *rreq, *rptr; + + m = a; + 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); + cb = NULL; + 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); + + if (req->cb) + (*req->cb) (req, req->cba); + else + kfree(req->rcall); + + wake_up(&m->equeue); + } + + kfree(freq->tcall); + kfree(freq->rcall); + p9_mux_free_request(m, freq); +} + +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); + if (req->cb) + (*req->cb) (req, req->cba); + return 0; + } + } + spin_unlock(&m->lock); + + clear_thread_flag(TIF_SIGPENDING); + fc = p9_create_tflush(req->tag); + p9_send_request(m, fc, p9_mux_flush_cb, m); + return 1; +} + +static void +p9_conn_rpc_cb(struct p9_req *req, void *a) +{ + struct p9_mux_rpc *r; + + P9_DPRINTK(P9_DEBUG_MUX, "req %p r %p\n", req, a); + r = a; + r->rcall = req->rcall; + r->err = req->err; + + if (req->flush != None && !req->err) + r->err = -ERESTARTSYS; + + wake_up(&r->wqueue); +} + +/** + * p9_fd_rpc- sends 9P request and waits until a response is available. + * The function can be interrupted. + * @m: mux data + * @tc: request to be sent + * @rc: pointer where a pointer to the response is stored + */ +int +p9_fd_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc) +{ + struct p9_trans_fd *p = t->priv; + struct p9_conn *m = p->conn; + int err, sigpending; + unsigned long flags; + struct p9_req *req; + struct p9_mux_rpc r; + + r.err = 0; + r.tcall = tc; + r.rcall = NULL; + r.m = m; + init_waitqueue_head(&r.wqueue); + + if (rc) + *rc = NULL; + + sigpending = 0; + if (signal_pending(current)) { + sigpending = 1; + clear_thread_flag(TIF_SIGPENDING); + } + + req = p9_send_request(m, tc, p9_conn_rpc_cb, &r); + if (IS_ERR(req)) { + err = PTR_ERR(req); + P9_DPRINTK(P9_DEBUG_MUX, "error %d\n", err); + return err; + } + + err = wait_event_interruptible(r.wqueue, r.rcall != NULL || r.err < 0); + if (r.err < 0) + err = r.err; + + if (err == -ERESTARTSYS && m->trans->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(r.wqueue, + r.rcall || r.err); + } while (!r.rcall && !r.err && err == -ERESTARTSYS && + m->trans->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 = r.rcall; + else + kfree(r.rcall); + + p9_mux_free_request(m, req); + if (err > 0) + err = -EIO; + + return err; +} + +#ifdef P9_NONBLOCK +/** + * p9_conn_rpcnb - sends 9P request without waiting for response. + * @m: mux data + * @tc: request to be sent + * @cb: callback function to be called when response arrives + * @cba: value to pass to the callback function + */ +int p9_conn_rpcnb(struct p9_conn *m, struct p9_fcall *tc, + p9_conn_req_callback cb, void *a) +{ + int err; + struct p9_req *req; + + req = p9_send_request(m, tc, cb, a); + if (IS_ERR(req)) { + err = PTR_ERR(req); + P9_DPRINTK(P9_DEBUG_MUX, "error %d\n", err); + return PTR_ERR(req); + } + + P9_DPRINTK(P9_DEBUG_MUX, "mux %p tc %p tag %d\n", m, tc, req->tag); + return 0; +} +#endif /* P9_NONBLOCK */ + +/** + * 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; + + if (req->cb) + (*req->cb) (req, req->cba); + else + kfree(req->rcall); + } + + wake_up(&m->equeue); +} + /** * v9fs_parse_options - parse mount options into session structure * @options: options string passed from mount @@ -268,7 +1294,7 @@ end: } /** - * p9_sock_close - shutdown socket + * p9_fd_close - shutdown socket * @trans: private socket structure * */ @@ -284,6 +1310,8 @@ static void p9_fd_close(struct p9_trans *trans) if (!ts) return; + p9_conn_destroy(ts->conn); + trans->status = Disconnected; if (ts->rd) fput(ts->rd); @@ -292,13 +1320,15 @@ static void p9_fd_close(struct p9_trans *trans) kfree(ts); } -static struct p9_trans *p9_trans_create_tcp(const char *addr, char *args) +static struct p9_trans * +p9_trans_create_tcp(const char *addr, char *args, int msize, unsigned char dotu) { int err; struct p9_trans *trans; struct socket *csocket; struct sockaddr_in sin_server; struct p9_fd_opts opts; + struct p9_trans_fd *p; parse_opts(args, &opts); @@ -306,11 +1336,10 @@ static struct p9_trans *p9_trans_create_tcp(const char *addr, char *args) trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL); if (!trans) return ERR_PTR(-ENOMEM); - - trans->write = p9_fd_write; - trans->read = p9_fd_read; + trans->msize = msize; + trans->extended = dotu; + trans->rpc = p9_fd_rpc; trans->close = p9_fd_close; - trans->poll = p9_fd_poll; sin_server.sin_family = AF_INET; sin_server.sin_addr.s_addr = in_aton(addr); @@ -337,6 +1366,14 @@ static struct p9_trans *p9_trans_create_tcp(const char *addr, char *args) if (err < 0) goto error; + p = (struct p9_trans_fd *) trans->priv; + p->conn = p9_conn_create(trans); + if (IS_ERR(p->conn)) { + err = PTR_ERR(p->conn); + p->conn = NULL; + goto error; + } + return trans; error: @@ -347,22 +1384,23 @@ error: return ERR_PTR(err); } -static struct p9_trans *p9_trans_create_unix(const char *addr, char *args) +static struct p9_trans * +p9_trans_create_unix(const char *addr, char *args, int msize, + unsigned char dotu) { int err; struct socket *csocket; struct sockaddr_un sun_server; struct p9_trans *trans; + struct p9_trans_fd *p; csocket = NULL; trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL); if (!trans) return ERR_PTR(-ENOMEM); - trans->write = p9_fd_write; - trans->read = p9_fd_read; + trans->rpc = p9_fd_rpc; trans->close = p9_fd_close; - trans->poll = p9_fd_poll; if (strlen(addr) > UNIX_PATH_MAX) { P9_EPRINTK(KERN_ERR, "p9_trans_unix: address too long: %s\n", @@ -387,6 +1425,16 @@ static struct p9_trans *p9_trans_create_unix(const char *addr, char *args) if (err < 0) goto error; + trans->msize = msize; + trans->extended = dotu; + p = (struct p9_trans_fd *) trans->priv; + p->conn = p9_conn_create(trans); + if (IS_ERR(p->conn)) { + err = PTR_ERR(p->conn); + p->conn = NULL; + goto error; + } + return trans; error: @@ -397,11 +1445,14 @@ error: return ERR_PTR(err); } -static struct p9_trans *p9_trans_create_fd(const char *name, char *args) +static struct p9_trans * +p9_trans_create_fd(const char *name, char *args, int msize, + unsigned char extended) { int err; struct p9_trans *trans; struct p9_fd_opts opts; + struct p9_trans_fd *p; parse_opts(args, &opts); @@ -414,15 +1465,23 @@ static struct p9_trans *p9_trans_create_fd(const char *name, char *args) if (!trans) return ERR_PTR(-ENOMEM); - trans->write = p9_fd_write; - trans->read = p9_fd_read; + trans->rpc = p9_fd_rpc; trans->close = p9_fd_close; - trans->poll = p9_fd_poll; err = p9_fd_open(trans, opts.rfd, opts.wfd); if (err < 0) goto error; + trans->msize = msize; + trans->extended = extended; + p = (struct p9_trans_fd *) trans->priv; + p->conn = p9_conn_create(trans); + if (IS_ERR(p->conn)) { + err = PTR_ERR(p->conn); + p->conn = NULL; + goto error; + } + return trans; error: @@ -453,6 +1512,12 @@ static struct p9_trans_module p9_fd_trans = { static int __init p9_trans_fd_init(void) { + int ret = p9_mux_global_init(); + if (ret) { + printk(KERN_WARNING "9p: starting mux failed\n"); + return ret; + } + v9fs_register_trans(&p9_tcp_trans); v9fs_register_trans(&p9_unix_trans); v9fs_register_trans(&p9_fd_trans); @@ -460,13 +1525,7 @@ static int __init p9_trans_fd_init(void) return 1; } -static void __exit p9_trans_fd_exit(void) { - printk(KERN_ERR "Removal of 9p transports not implemented\n"); - BUG(); -} - module_init(p9_trans_fd_init); -module_exit(p9_trans_fd_exit); MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>"); MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>"); |