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1275 |
phoenix |
/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
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* vim:expandtab:shiftwidth=8:tabstop=8:
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*
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* An implementation of a loadable kernel mode driver providing
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* multiple kernel/user space bidirectional communications links.
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*
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* Author: Alan Cox <alan@cymru.net>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* version 2 as published by the Free Software Foundation.
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*
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* Adapted to become the Linux 2.0 Coda pseudo device
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* Peter Braam <braam@maths.ox.ac.uk>
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* Michael Callahan <mjc@emmy.smith.edu>
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*
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* Changes for Linux 2.1
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* Copyright (c) 1997 Carnegie-Mellon University
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*
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* Redone again for InterMezzo
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* Copyright (c) 1998 Peter J. Braam
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* Copyright (c) 2000 Mountain View Data, Inc.
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* Copyright (c) 2000 Tacitus Systems, Inc.
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* Copyright (c) 2001 Cluster File Systems, Inc.
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*
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*/
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/major.h>
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#include <linux/sched.h>
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#include <linux/lp.h>
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#include <linux/slab.h>
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#include <linux/ioport.h>
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#include <linux/fcntl.h>
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#include <linux/delay.h>
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#include <linux/skbuff.h>
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#include <linux/proc_fs.h>
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#include <linux/vmalloc.h>
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#include <linux/fs.h>
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#include <linux/file.h>
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#include <linux/poll.h>
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#include <linux/init.h>
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#include <linux/list.h>
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#include <linux/devfs_fs_kernel.h>
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#include <asm/io.h>
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#include <asm/segment.h>
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#include <asm/system.h>
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#include <asm/poll.h>
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#include <asm/uaccess.h>
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#include <linux/miscdevice.h>
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#include <linux/intermezzo_fs.h>
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#include <linux/intermezzo_psdev.h>
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#ifdef PRESTO_DEVEL
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int presto_print_entry = 1;
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int presto_debug = 4095;
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#else
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int presto_print_entry = 0;
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int presto_debug = 0;
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#endif
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/* Like inode.c (presto_sym_iops), the initializer is just to prevent
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izo_channels from appearing as a COMMON symbol (and therefore
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interfering with other modules that use the same variable name). */
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struct upc_channel izo_channels[MAX_CHANNEL] = {{0}};
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int izo_psdev_get_free_channel(void)
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{
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int i, result = -1;
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for (i = 0 ; i < MAX_CHANNEL ; i++ ) {
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if (list_empty(&(izo_channels[i].uc_cache_list))) {
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result = i;
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break;
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}
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}
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return result;
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}
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int izo_psdev_setpid(int minor)
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{
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struct upc_channel *channel;
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if (minor < 0 || minor >= MAX_CHANNEL) {
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return -EINVAL;
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}
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channel = &(izo_channels[minor]);
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/*
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* This ioctl is performed by each Lento that starts up
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* and wants to do further communication with presto.
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*/
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CDEBUG(D_PSDEV, "Setting current pid to %d channel %d\n",
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current->pid, minor);
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channel->uc_pid = current->pid;
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spin_lock(&channel->uc_lock);
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if ( !list_empty(&channel->uc_processing) ) {
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struct list_head *lh;
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struct upc_req *req;
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CERROR("WARNING: setpid & processing not empty!\n");
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lh = &channel->uc_processing;
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while ( (lh = lh->next) != &channel->uc_processing) {
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req = list_entry(lh, struct upc_req, rq_chain);
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/* freeing of req and data is done by the sleeper */
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wake_up(&req->rq_sleep);
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}
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}
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if ( !list_empty(&channel->uc_processing) ) {
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CERROR("BAD: FAILDED TO CLEAN PROCESSING LIST!\n");
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}
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spin_unlock(&channel->uc_lock);
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EXIT;
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return 0;
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}
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int izo_psdev_setchannel(struct file *file, int fd)
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{
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struct file *psdev_file = fget(fd);
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struct presto_cache *cache = presto_get_cache(file->f_dentry->d_inode);
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if (!psdev_file) {
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CERROR("%s: no psdev_file!\n", __FUNCTION__);
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return -EINVAL;
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}
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if (!cache) {
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CERROR("%s: no cache!\n", __FUNCTION__);
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fput(psdev_file);
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return -EINVAL;
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}
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if (psdev_file->private_data) {
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CERROR("%s: channel already set!\n", __FUNCTION__);
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fput(psdev_file);
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return -EINVAL;
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}
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psdev_file->private_data = cache->cache_psdev;
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fput(psdev_file);
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EXIT;
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return 0;
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}
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inline int presto_lento_up(int minor)
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{
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return izo_channels[minor].uc_pid;
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}
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static unsigned int presto_psdev_poll(struct file *file, poll_table * wait)
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{
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struct upc_channel *channel = (struct upc_channel *)file->private_data;
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unsigned int mask = POLLOUT | POLLWRNORM;
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/* ENTRY; this will flood you */
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if ( ! channel ) {
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CERROR("%s: bad psdev file\n", __FUNCTION__);
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return -EBADF;
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}
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poll_wait(file, &(channel->uc_waitq), wait);
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spin_lock(&channel->uc_lock);
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if (!list_empty(&channel->uc_pending)) {
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CDEBUG(D_PSDEV, "Non-empty pending list.\n");
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mask |= POLLIN | POLLRDNORM;
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}
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spin_unlock(&channel->uc_lock);
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/* EXIT; will flood you */
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return mask;
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}
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/*
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* Receive a message written by Lento to the psdev
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*/
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static ssize_t presto_psdev_write(struct file *file, const char *buf,
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size_t count, loff_t *off)
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{
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struct upc_channel *channel = (struct upc_channel *)file->private_data;
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struct upc_req *req = NULL;
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struct upc_req *tmp;
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struct list_head *lh;
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struct izo_upcall_resp hdr;
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int error;
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if ( ! channel ) {
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CERROR("%s: bad psdev file\n", __FUNCTION__);
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return -EBADF;
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}
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/* Peek at the opcode, uniquefier */
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if ( count < sizeof(hdr) ) {
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CERROR("presto_psdev_write: Lento didn't write full hdr.\n");
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return -EINVAL;
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}
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error = copy_from_user(&hdr, buf, sizeof(hdr));
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if ( error )
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return -EFAULT;
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CDEBUG(D_PSDEV, "(process,opc,uniq)=(%d,%d,%d)\n",
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current->pid, hdr.opcode, hdr.unique);
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209 |
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spin_lock(&channel->uc_lock);
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/* Look for the message on the processing queue. */
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lh = &channel->uc_processing;
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while ( (lh = lh->next) != &channel->uc_processing ) {
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tmp = list_entry(lh, struct upc_req , rq_chain);
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if (tmp->rq_unique == hdr.unique) {
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215 |
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req = tmp;
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216 |
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/* unlink here: keeps search length minimal */
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217 |
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list_del_init(&req->rq_chain);
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218 |
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CDEBUG(D_PSDEV,"Eureka opc %d uniq %d!\n",
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hdr.opcode, hdr.unique);
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break;
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221 |
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}
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222 |
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}
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223 |
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spin_unlock(&channel->uc_lock);
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224 |
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if (!req) {
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225 |
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CERROR("psdev_write: msg (%d, %d) not found\n",
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hdr.opcode, hdr.unique);
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227 |
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return(-ESRCH);
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228 |
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}
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229 |
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230 |
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/* move data into response buffer. */
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231 |
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if (req->rq_bufsize < count) {
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232 |
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CERROR("psdev_write: too much cnt: %d, cnt: %d, "
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233 |
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"opc: %d, uniq: %d.\n",
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req->rq_bufsize, count, hdr.opcode, hdr.unique);
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235 |
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count = req->rq_bufsize; /* don't have more space! */
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236 |
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}
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237 |
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error = copy_from_user(req->rq_data, buf, count);
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238 |
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if ( error )
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239 |
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return -EFAULT;
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240 |
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241 |
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/* adjust outsize: good upcalls can be aware of this */
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242 |
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req->rq_rep_size = count;
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243 |
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req->rq_flags |= REQ_WRITE;
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244 |
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245 |
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wake_up(&req->rq_sleep);
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246 |
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return(count);
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247 |
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}
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248 |
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|
249 |
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/*
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250 |
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* Read a message from the kernel to Lento
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251 |
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*/
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252 |
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static ssize_t presto_psdev_read(struct file * file, char * buf,
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253 |
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size_t count, loff_t *off)
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254 |
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{
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255 |
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struct upc_channel *channel = (struct upc_channel *)file->private_data;
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256 |
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struct upc_req *req;
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257 |
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int result = count;
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258 |
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259 |
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if ( ! channel ) {
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260 |
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CERROR("%s: bad psdev file\n", __FUNCTION__);
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261 |
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return -EBADF;
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262 |
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}
|
263 |
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|
264 |
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spin_lock(&channel->uc_lock);
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265 |
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if (list_empty(&(channel->uc_pending))) {
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266 |
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CDEBUG(D_UPCALL, "Empty pending list in read, not good\n");
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267 |
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spin_unlock(&channel->uc_lock);
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268 |
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return -EINVAL;
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269 |
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}
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270 |
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req = list_entry((channel->uc_pending.next), struct upc_req, rq_chain);
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271 |
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list_del(&(req->rq_chain));
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272 |
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if (! (req->rq_flags & REQ_ASYNC) ) {
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273 |
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list_add(&(req->rq_chain), channel->uc_processing.prev);
|
274 |
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}
|
275 |
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spin_unlock(&channel->uc_lock);
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276 |
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|
277 |
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req->rq_flags |= REQ_READ;
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278 |
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|
279 |
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/* Move the input args into userspace */
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280 |
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CDEBUG(D_PSDEV, "\n");
|
281 |
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if (req->rq_bufsize <= count) {
|
282 |
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result = req->rq_bufsize;
|
283 |
|
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}
|
284 |
|
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|
285 |
|
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if (count < req->rq_bufsize) {
|
286 |
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CERROR ("psdev_read: buffer too small, read %d of %d bytes\n",
|
287 |
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count, req->rq_bufsize);
|
288 |
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}
|
289 |
|
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|
290 |
|
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if ( copy_to_user(buf, req->rq_data, result) ) {
|
291 |
|
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BUG();
|
292 |
|
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return -EFAULT;
|
293 |
|
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}
|
294 |
|
|
|
295 |
|
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/* If request was asynchronous don't enqueue, but free */
|
296 |
|
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if (req->rq_flags & REQ_ASYNC) {
|
297 |
|
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CDEBUG(D_PSDEV, "psdev_read: async msg (%d, %d), result %d\n",
|
298 |
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req->rq_opcode, req->rq_unique, result);
|
299 |
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PRESTO_FREE(req->rq_data, req->rq_bufsize);
|
300 |
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PRESTO_FREE(req, sizeof(*req));
|
301 |
|
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return result;
|
302 |
|
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}
|
303 |
|
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|
304 |
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return result;
|
305 |
|
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}
|
306 |
|
|
|
307 |
|
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|
308 |
|
|
static int presto_psdev_open(struct inode * inode, struct file * file)
|
309 |
|
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{
|
310 |
|
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ENTRY;
|
311 |
|
|
|
312 |
|
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file->private_data = NULL;
|
313 |
|
|
|
314 |
|
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MOD_INC_USE_COUNT;
|
315 |
|
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|
316 |
|
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CDEBUG(D_PSDEV, "Psdev_open: caller: %d, flags: %d\n", current->pid, file->f_flags);
|
317 |
|
|
|
318 |
|
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EXIT;
|
319 |
|
|
return 0;
|
320 |
|
|
}
|
321 |
|
|
|
322 |
|
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|
323 |
|
|
|
324 |
|
|
static int presto_psdev_release(struct inode * inode, struct file * file)
|
325 |
|
|
{
|
326 |
|
|
struct upc_channel *channel = (struct upc_channel *)file->private_data;
|
327 |
|
|
struct upc_req *req;
|
328 |
|
|
struct list_head *lh;
|
329 |
|
|
ENTRY;
|
330 |
|
|
|
331 |
|
|
if ( ! channel ) {
|
332 |
|
|
CERROR("%s: bad psdev file\n", __FUNCTION__);
|
333 |
|
|
return -EBADF;
|
334 |
|
|
}
|
335 |
|
|
|
336 |
|
|
MOD_DEC_USE_COUNT;
|
337 |
|
|
CDEBUG(D_PSDEV, "Lento: pid %d\n", current->pid);
|
338 |
|
|
channel->uc_pid = 0;
|
339 |
|
|
|
340 |
|
|
/* Wake up clients so they can return. */
|
341 |
|
|
CDEBUG(D_PSDEV, "Wake up clients sleeping for pending.\n");
|
342 |
|
|
spin_lock(&channel->uc_lock);
|
343 |
|
|
lh = &channel->uc_pending;
|
344 |
|
|
while ( (lh = lh->next) != &channel->uc_pending) {
|
345 |
|
|
req = list_entry(lh, struct upc_req, rq_chain);
|
346 |
|
|
|
347 |
|
|
/* Async requests stay around for a new lento */
|
348 |
|
|
if (req->rq_flags & REQ_ASYNC) {
|
349 |
|
|
continue;
|
350 |
|
|
}
|
351 |
|
|
/* the sleeper will free the req and data */
|
352 |
|
|
req->rq_flags |= REQ_DEAD;
|
353 |
|
|
wake_up(&req->rq_sleep);
|
354 |
|
|
}
|
355 |
|
|
|
356 |
|
|
CDEBUG(D_PSDEV, "Wake up clients sleeping for processing\n");
|
357 |
|
|
lh = &channel->uc_processing;
|
358 |
|
|
while ( (lh = lh->next) != &channel->uc_processing) {
|
359 |
|
|
req = list_entry(lh, struct upc_req, rq_chain);
|
360 |
|
|
/* freeing of req and data is done by the sleeper */
|
361 |
|
|
req->rq_flags |= REQ_DEAD;
|
362 |
|
|
wake_up(&req->rq_sleep);
|
363 |
|
|
}
|
364 |
|
|
spin_unlock(&channel->uc_lock);
|
365 |
|
|
CDEBUG(D_PSDEV, "Done.\n");
|
366 |
|
|
|
367 |
|
|
EXIT;
|
368 |
|
|
return 0;
|
369 |
|
|
}
|
370 |
|
|
|
371 |
|
|
static struct file_operations presto_psdev_fops = {
|
372 |
|
|
.read = presto_psdev_read,
|
373 |
|
|
.write = presto_psdev_write,
|
374 |
|
|
.poll = presto_psdev_poll,
|
375 |
|
|
.open = presto_psdev_open,
|
376 |
|
|
.release = presto_psdev_release
|
377 |
|
|
};
|
378 |
|
|
|
379 |
|
|
/* modules setup */
|
380 |
|
|
static struct miscdevice intermezzo_psdev = {
|
381 |
|
|
INTERMEZZO_MINOR,
|
382 |
|
|
"intermezzo",
|
383 |
|
|
&presto_psdev_fops
|
384 |
|
|
};
|
385 |
|
|
|
386 |
|
|
int presto_psdev_init(void)
|
387 |
|
|
{
|
388 |
|
|
int i;
|
389 |
|
|
int err;
|
390 |
|
|
|
391 |
|
|
if ( (err = misc_register(&intermezzo_psdev)) ) {
|
392 |
|
|
CERROR("%s: cannot register %d err %d\n",
|
393 |
|
|
__FUNCTION__, INTERMEZZO_MINOR, err);
|
394 |
|
|
return -EIO;
|
395 |
|
|
}
|
396 |
|
|
|
397 |
|
|
memset(&izo_channels, 0, sizeof(izo_channels));
|
398 |
|
|
for ( i = 0 ; i < MAX_CHANNEL ; i++ ) {
|
399 |
|
|
struct upc_channel *channel = &(izo_channels[i]);
|
400 |
|
|
INIT_LIST_HEAD(&channel->uc_pending);
|
401 |
|
|
INIT_LIST_HEAD(&channel->uc_processing);
|
402 |
|
|
INIT_LIST_HEAD(&channel->uc_cache_list);
|
403 |
|
|
init_waitqueue_head(&channel->uc_waitq);
|
404 |
|
|
channel->uc_lock = SPIN_LOCK_UNLOCKED;
|
405 |
|
|
channel->uc_hard = 0;
|
406 |
|
|
channel->uc_no_filter = 0;
|
407 |
|
|
channel->uc_no_journal = 0;
|
408 |
|
|
channel->uc_no_upcall = 0;
|
409 |
|
|
channel->uc_timeout = 30;
|
410 |
|
|
channel->uc_errorval = 0;
|
411 |
|
|
channel->uc_minor = i;
|
412 |
|
|
}
|
413 |
|
|
return 0;
|
414 |
|
|
}
|
415 |
|
|
|
416 |
|
|
void presto_psdev_cleanup(void)
|
417 |
|
|
{
|
418 |
|
|
int i;
|
419 |
|
|
|
420 |
|
|
misc_deregister(&intermezzo_psdev);
|
421 |
|
|
|
422 |
|
|
for ( i = 0 ; i < MAX_CHANNEL ; i++ ) {
|
423 |
|
|
struct upc_channel *channel = &(izo_channels[i]);
|
424 |
|
|
struct list_head *lh;
|
425 |
|
|
|
426 |
|
|
spin_lock(&channel->uc_lock);
|
427 |
|
|
if ( ! list_empty(&channel->uc_pending)) {
|
428 |
|
|
CERROR("Weird, tell Peter: module cleanup and pending list not empty dev %d\n", i);
|
429 |
|
|
}
|
430 |
|
|
if ( ! list_empty(&channel->uc_processing)) {
|
431 |
|
|
CERROR("Weird, tell Peter: module cleanup and processing list not empty dev %d\n", i);
|
432 |
|
|
}
|
433 |
|
|
if ( ! list_empty(&channel->uc_cache_list)) {
|
434 |
|
|
CERROR("Weird, tell Peter: module cleanup and cache listnot empty dev %d\n", i);
|
435 |
|
|
}
|
436 |
|
|
lh = channel->uc_pending.next;
|
437 |
|
|
while ( lh != &channel->uc_pending) {
|
438 |
|
|
struct upc_req *req;
|
439 |
|
|
|
440 |
|
|
req = list_entry(lh, struct upc_req, rq_chain);
|
441 |
|
|
lh = lh->next;
|
442 |
|
|
if ( req->rq_flags & REQ_ASYNC ) {
|
443 |
|
|
list_del(&(req->rq_chain));
|
444 |
|
|
CDEBUG(D_UPCALL, "free pending upcall type %d\n",
|
445 |
|
|
req->rq_opcode);
|
446 |
|
|
PRESTO_FREE(req->rq_data, req->rq_bufsize);
|
447 |
|
|
PRESTO_FREE(req, sizeof(struct upc_req));
|
448 |
|
|
} else {
|
449 |
|
|
req->rq_flags |= REQ_DEAD;
|
450 |
|
|
wake_up(&req->rq_sleep);
|
451 |
|
|
}
|
452 |
|
|
}
|
453 |
|
|
lh = &channel->uc_processing;
|
454 |
|
|
while ( (lh = lh->next) != &channel->uc_processing ) {
|
455 |
|
|
struct upc_req *req;
|
456 |
|
|
req = list_entry(lh, struct upc_req, rq_chain);
|
457 |
|
|
list_del(&(req->rq_chain));
|
458 |
|
|
req->rq_flags |= REQ_DEAD;
|
459 |
|
|
wake_up(&req->rq_sleep);
|
460 |
|
|
}
|
461 |
|
|
spin_unlock(&channel->uc_lock);
|
462 |
|
|
}
|
463 |
|
|
}
|
464 |
|
|
|
465 |
|
|
/*
|
466 |
|
|
* lento_upcall and lento_downcall routines
|
467 |
|
|
*/
|
468 |
|
|
static inline unsigned long lento_waitfor_upcall
|
469 |
|
|
(struct upc_channel *channel, struct upc_req *req, int minor)
|
470 |
|
|
{
|
471 |
|
|
DECLARE_WAITQUEUE(wait, current);
|
472 |
|
|
unsigned long posttime;
|
473 |
|
|
|
474 |
|
|
req->rq_posttime = posttime = jiffies;
|
475 |
|
|
|
476 |
|
|
add_wait_queue(&req->rq_sleep, &wait);
|
477 |
|
|
for (;;) {
|
478 |
|
|
if ( izo_channels[minor].uc_hard == 0 )
|
479 |
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
480 |
|
|
else
|
481 |
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
482 |
|
|
|
483 |
|
|
/* got a reply */
|
484 |
|
|
if ( req->rq_flags & (REQ_WRITE | REQ_DEAD) )
|
485 |
|
|
break;
|
486 |
|
|
|
487 |
|
|
/* these cases only apply when TASK_INTERRUPTIBLE */
|
488 |
|
|
if ( !izo_channels[minor].uc_hard && signal_pending(current) ) {
|
489 |
|
|
/* if this process really wants to die, let it go */
|
490 |
|
|
if (sigismember(&(current->pending.signal), SIGKILL)||
|
491 |
|
|
sigismember(&(current->pending.signal), SIGINT) )
|
492 |
|
|
break;
|
493 |
|
|
/* signal is present: after timeout always return
|
494 |
|
|
really smart idea, probably useless ... */
|
495 |
|
|
if ( time_after(jiffies, req->rq_posttime +
|
496 |
|
|
izo_channels[minor].uc_timeout * HZ) )
|
497 |
|
|
break;
|
498 |
|
|
}
|
499 |
|
|
schedule();
|
500 |
|
|
}
|
501 |
|
|
|
502 |
|
|
spin_lock(&channel->uc_lock);
|
503 |
|
|
list_del_init(&req->rq_chain);
|
504 |
|
|
spin_unlock(&channel->uc_lock);
|
505 |
|
|
remove_wait_queue(&req->rq_sleep, &wait);
|
506 |
|
|
set_current_state(TASK_RUNNING);
|
507 |
|
|
|
508 |
|
|
CDEBUG(D_SPECIAL, "posttime: %ld, returned: %ld\n",
|
509 |
|
|
posttime, jiffies-posttime);
|
510 |
|
|
return (jiffies - posttime);
|
511 |
|
|
}
|
512 |
|
|
|
513 |
|
|
/*
|
514 |
|
|
* lento_upcall will return an error in the case of
|
515 |
|
|
* failed communication with Lento _or_ will peek at Lento
|
516 |
|
|
* reply and return Lento's error.
|
517 |
|
|
*
|
518 |
|
|
* As lento has 2 types of errors, normal errors (positive) and internal
|
519 |
|
|
* errors (negative), normal errors are negated, while internal errors
|
520 |
|
|
* are all mapped to -EINTR, while showing a nice warning message. (jh)
|
521 |
|
|
*
|
522 |
|
|
* lento_upcall will always free buffer, either directly, when an upcall
|
523 |
|
|
* is read (in presto_psdev_read), when the filesystem is unmounted, or
|
524 |
|
|
* when the module is unloaded.
|
525 |
|
|
*/
|
526 |
|
|
int izo_upc_upcall(int minor, int *size, struct izo_upcall_hdr *buffer,
|
527 |
|
|
int async)
|
528 |
|
|
{
|
529 |
|
|
unsigned long runtime;
|
530 |
|
|
struct upc_channel *channel;
|
531 |
|
|
struct izo_upcall_resp *out;
|
532 |
|
|
struct upc_req *req;
|
533 |
|
|
int error = 0;
|
534 |
|
|
|
535 |
|
|
ENTRY;
|
536 |
|
|
channel = &(izo_channels[minor]);
|
537 |
|
|
|
538 |
|
|
if (channel->uc_no_upcall) {
|
539 |
|
|
EXIT;
|
540 |
|
|
goto exit_buf;
|
541 |
|
|
}
|
542 |
|
|
if (!channel->uc_pid && !async) {
|
543 |
|
|
EXIT;
|
544 |
|
|
error = -ENXIO;
|
545 |
|
|
goto exit_buf;
|
546 |
|
|
}
|
547 |
|
|
|
548 |
|
|
/* Format the request message. */
|
549 |
|
|
PRESTO_ALLOC(req, sizeof(struct upc_req));
|
550 |
|
|
if ( !req ) {
|
551 |
|
|
EXIT;
|
552 |
|
|
error = -ENOMEM;
|
553 |
|
|
goto exit_buf;
|
554 |
|
|
}
|
555 |
|
|
req->rq_data = (void *)buffer;
|
556 |
|
|
req->rq_flags = 0;
|
557 |
|
|
req->rq_bufsize = *size;
|
558 |
|
|
req->rq_rep_size = 0;
|
559 |
|
|
req->rq_opcode = buffer->u_opc;
|
560 |
|
|
req->rq_unique = ++channel->uc_seq;
|
561 |
|
|
init_waitqueue_head(&req->rq_sleep);
|
562 |
|
|
|
563 |
|
|
/* Fill in the common input args. */
|
564 |
|
|
buffer->u_uniq = req->rq_unique;
|
565 |
|
|
buffer->u_async = async;
|
566 |
|
|
|
567 |
|
|
spin_lock(&channel->uc_lock);
|
568 |
|
|
/* Append msg to pending queue and poke Lento. */
|
569 |
|
|
list_add(&req->rq_chain, channel->uc_pending.prev);
|
570 |
|
|
spin_unlock(&channel->uc_lock);
|
571 |
|
|
CDEBUG(D_UPCALL,
|
572 |
|
|
"Proc %d waking Lento %d for(opc,uniq) =(%d,%d) msg at %p.\n",
|
573 |
|
|
current->pid, channel->uc_pid, req->rq_opcode,
|
574 |
|
|
req->rq_unique, req);
|
575 |
|
|
wake_up_interruptible(&channel->uc_waitq);
|
576 |
|
|
|
577 |
|
|
if ( async ) {
|
578 |
|
|
/* req, rq_data are freed in presto_psdev_read for async */
|
579 |
|
|
req->rq_flags = REQ_ASYNC;
|
580 |
|
|
EXIT;
|
581 |
|
|
return 0;
|
582 |
|
|
}
|
583 |
|
|
|
584 |
|
|
/* We can be interrupted while we wait for Lento to process
|
585 |
|
|
* our request. If the interrupt occurs before Lento has read
|
586 |
|
|
* the request, we dequeue and return. If it occurs after the
|
587 |
|
|
* read but before the reply, we dequeue, send a signal
|
588 |
|
|
* message, and return. If it occurs after the reply we ignore
|
589 |
|
|
* it. In no case do we want to restart the syscall. If it
|
590 |
|
|
* was interrupted by a lento shutdown (psdev_close), return
|
591 |
|
|
* ENODEV. */
|
592 |
|
|
|
593 |
|
|
/* Go to sleep. Wake up on signals only after the timeout. */
|
594 |
|
|
runtime = lento_waitfor_upcall(channel, req, minor);
|
595 |
|
|
|
596 |
|
|
CDEBUG(D_TIMING, "opc: %d time: %ld uniq: %d size: %d\n",
|
597 |
|
|
req->rq_opcode, jiffies - req->rq_posttime,
|
598 |
|
|
req->rq_unique, req->rq_rep_size);
|
599 |
|
|
CDEBUG(D_UPCALL,
|
600 |
|
|
"..process %d woken up by Lento for req at 0x%x, data at %x\n",
|
601 |
|
|
current->pid, (int)req, (int)req->rq_data);
|
602 |
|
|
|
603 |
|
|
if (channel->uc_pid) { /* i.e. Lento is still alive */
|
604 |
|
|
/* Op went through, interrupt or not we go on */
|
605 |
|
|
if (req->rq_flags & REQ_WRITE) {
|
606 |
|
|
out = (struct izo_upcall_resp *)req->rq_data;
|
607 |
|
|
/* here we map positive Lento errors to kernel errors */
|
608 |
|
|
if ( out->result < 0 ) {
|
609 |
|
|
CERROR("Tell Peter: Lento returns negative error %d, for oc %d!\n",
|
610 |
|
|
out->result, out->opcode);
|
611 |
|
|
out->result = EINVAL;
|
612 |
|
|
}
|
613 |
|
|
error = -out->result;
|
614 |
|
|
CDEBUG(D_UPCALL, "upcall: (u,o,r) (%d, %d, %d) out at %p\n",
|
615 |
|
|
out->unique, out->opcode, out->result, out);
|
616 |
|
|
*size = req->rq_rep_size;
|
617 |
|
|
EXIT;
|
618 |
|
|
goto exit_req;
|
619 |
|
|
}
|
620 |
|
|
/* Interrupted before lento read it. */
|
621 |
|
|
if ( !(req->rq_flags & REQ_READ) && signal_pending(current)) {
|
622 |
|
|
CDEBUG(D_UPCALL,
|
623 |
|
|
"Interrupt before read: (op,un)=(%d,%d), flags %x\n",
|
624 |
|
|
req->rq_opcode, req->rq_unique, req->rq_flags);
|
625 |
|
|
/* perhaps the best way to convince the app to give up? */
|
626 |
|
|
error = -EINTR;
|
627 |
|
|
EXIT;
|
628 |
|
|
goto exit_req;
|
629 |
|
|
}
|
630 |
|
|
|
631 |
|
|
/* interrupted after Lento did its read, send signal */
|
632 |
|
|
if ( (req->rq_flags & REQ_READ) && signal_pending(current) ) {
|
633 |
|
|
CDEBUG(D_UPCALL,"Interrupt after read: op = %d.%d, flags = %x\n",
|
634 |
|
|
req->rq_opcode, req->rq_unique, req->rq_flags);
|
635 |
|
|
|
636 |
|
|
error = -EINTR;
|
637 |
|
|
} else {
|
638 |
|
|
CERROR("Lento: Strange interruption - tell Peter.\n");
|
639 |
|
|
error = -EINTR;
|
640 |
|
|
}
|
641 |
|
|
} else { /* If lento died i.e. !UC_OPEN(channel) */
|
642 |
|
|
CERROR("lento_upcall: Lento dead on (op,un) (%d.%d) flags %d\n",
|
643 |
|
|
req->rq_opcode, req->rq_unique, req->rq_flags);
|
644 |
|
|
error = -ENODEV;
|
645 |
|
|
}
|
646 |
|
|
|
647 |
|
|
exit_req:
|
648 |
|
|
PRESTO_FREE(req, sizeof(struct upc_req));
|
649 |
|
|
exit_buf:
|
650 |
|
|
return error;
|
651 |
|
|
}
|