Release 4.10 drivers/char/snsc.c

Directory: drivers/char
/*
 * SN Platform system controller communication support
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2004, 2006 Silicon Graphics, Inc. All rights reserved.
 */

/*
 * System controller communication driver
 *
 * This driver allows a user process to communicate with the system
 * controller (a.k.a. "IRouter") network in an SGI SN system.
 */

#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <asm/sn/io.h>
#include <asm/sn/sn_sal.h>
#include <asm/sn/module.h>
#include <asm/sn/geo.h>
#include <asm/sn/nodepda.h>
#include "snsc.h"


#define SYSCTL_BASENAME	"snsc"


#define SCDRV_BUFSZ	2048

#define SCDRV_TIMEOUT	1000

static DEFINE_MUTEX(scdrv_mutex);

static irqreturn_t

scdrv_interrupt(int irq, void *subch_data)
{
	struct subch_data_s *sd = subch_data;
	unsigned long flags;
	int status;

	spin_lock_irqsave(&sd->sd_rlock, flags);
	spin_lock(&sd->sd_wlock);
	status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);

	if (status > 0) {
		if (status & SAL_IROUTER_INTR_RECV) {
			wake_up(&sd->sd_rq);
		}
		if (status & SAL_IROUTER_INTR_XMIT) {
			ia64_sn_irtr_intr_disable
			    (sd->sd_nasid, sd->sd_subch,
			     SAL_IROUTER_INTR_XMIT);
			wake_up(&sd->sd_wq);
		}
	}
	spin_unlock(&sd->sd_wlock);
	spin_unlock_irqrestore(&sd->sd_rlock, flags);
	return IRQ_HANDLED;
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 132 100.00% 1 100.00%
Total 132 100.00% 1 100.00%

/*
 * scdrv_open
 *
 * Reserve a subchannel for system controller communication.
 */


static int

scdrv_open(struct inode *inode, struct file *file)
{
	struct sysctl_data_s *scd;
	struct subch_data_s *sd;
	int rv;

	/* look up device info for this device file */
	scd = container_of(inode->i_cdev, struct sysctl_data_s, scd_cdev);

	/* allocate memory for subchannel data */
	sd = kzalloc(sizeof (struct subch_data_s), GFP_KERNEL);
	if (sd == NULL) {
		printk("%s: couldn't allocate subchannel data\n",
		       __func__);
		return -ENOMEM;
	}

	/* initialize subch_data_s fields */
	sd->sd_nasid = scd->scd_nasid;
	sd->sd_subch = ia64_sn_irtr_open(scd->scd_nasid);

	if (sd->sd_subch < 0) {
		kfree(sd);
		printk("%s: couldn't allocate subchannel\n", __func__);
		return -EBUSY;
	}

	spin_lock_init(&sd->sd_rlock);
	spin_lock_init(&sd->sd_wlock);
	init_waitqueue_head(&sd->sd_rq);
	init_waitqueue_head(&sd->sd_wq);
	sema_init(&sd->sd_rbs, 1);
	sema_init(&sd->sd_wbs, 1);

	file->private_data = sd;

	/* hook this subchannel up to the system controller interrupt */
	mutex_lock(&scdrv_mutex);
	rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt,
			 IRQF_SHARED, SYSCTL_BASENAME, sd);
	if (rv) {
		ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);
		kfree(sd);
		printk("%s: irq request failed (%d)\n", __func__, rv);
		mutex_unlock(&scdrv_mutex);
		return -EBUSY;
	}
	mutex_unlock(&scdrv_mutex);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 230 90.91% 1 16.67%
arnd bergmann arnd bergmann 15 5.93% 1 16.67%
jonathan corbet jonathan corbet 3 1.19% 1 16.67%
harvey harrison harvey harrison 3 1.19% 1 16.67%
jes sorensen jes sorensen 1 0.40% 1 16.67%
thomas gleixner thomas gleixner 1 0.40% 1 16.67%
Total 253 100.00% 6 100.00%

/*
 * scdrv_release
 *
 * Release a previously-reserved subchannel.
 */


static int

scdrv_release(struct inode *inode, struct file *file)
{
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;
	int rv;

	/* free the interrupt */
	free_irq(SGI_UART_VECTOR, sd);

	/* ask SAL to close the subchannel */
	rv = ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);

	kfree(sd);
	return rv;
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 63 100.00% 1 100.00%
Total 63 100.00% 1 100.00%

/*
 * scdrv_read
 *
 * Called to read bytes from the open IRouter pipe.
 *
 */


static inline int

read_status_check(struct subch_data_s *sd, int *len)
{
	return ia64_sn_irtr_recv(sd->sd_nasid, sd->sd_subch, sd->sd_rb, len);
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 34 100.00% 1 100.00%
Total 34 100.00% 1 100.00%


static ssize_t

scdrv_read(struct file *file, char __user *buf, size_t count, loff_t *f_pos)
{
	int status;
	int len;
	unsigned long flags;
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;

	/* try to get control of the read buffer */
	if (down_trylock(&sd->sd_rbs)) {
		/* somebody else has it now;
                 * if we're non-blocking, then exit...
                 */
		if (file->f_flags & O_NONBLOCK) {
			return -EAGAIN;
		}
		/* ...or if we want to block, then do so here */
		if (down_interruptible(&sd->sd_rbs)) {
			/* something went wrong with wait */
			return -ERESTARTSYS;
		}
	}

	/* anything to read? */
	len = CHUNKSIZE;
	spin_lock_irqsave(&sd->sd_rlock, flags);
	status = read_status_check(sd, &len);

	/* if not, and we're blocking I/O, loop */
	while (status < 0) {
		DECLARE_WAITQUEUE(wait, current);

		if (file->f_flags & O_NONBLOCK) {
			spin_unlock_irqrestore(&sd->sd_rlock, flags);
			up(&sd->sd_rbs);
			return -EAGAIN;
		}

		len = CHUNKSIZE;
		set_current_state(TASK_INTERRUPTIBLE);
		add_wait_queue(&sd->sd_rq, &wait);
		spin_unlock_irqrestore(&sd->sd_rlock, flags);

		schedule_timeout(msecs_to_jiffies(SCDRV_TIMEOUT));

		remove_wait_queue(&sd->sd_rq, &wait);
		if (signal_pending(current)) {
			/* wait was interrupted */
			up(&sd->sd_rbs);
			return -ERESTARTSYS;
		}

		spin_lock_irqsave(&sd->sd_rlock, flags);
		status = read_status_check(sd, &len);
	}
	spin_unlock_irqrestore(&sd->sd_rlock, flags);

	if (len > 0) {
		/* we read something in the last read_status_check(); copy
                 * it out to user space
                 */
		if (count < len) {
			pr_debug("%s: only accepting %d of %d bytes\n",
				 __func__, (int) count, len);
		}
		len = min((int) count, len);
		if (copy_to_user(buf, sd->sd_rb, len))
			len = -EFAULT;
	}

	/* release the read buffer and wake anyone who might be
         * waiting for it
         */
	up(&sd->sd_rbs);

	/* return the number of characters read in */
	return len;
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 332 97.36% 1 25.00%
domen puncer domen puncer 5 1.47% 1 25.00%
nicholas mc guire nicholas mc guire 3 0.88% 1 25.00%
harvey harrison harvey harrison 1 0.29% 1 25.00%
Total 341 100.00% 4 100.00%

/*
 * scdrv_write
 *
 * Writes a chunk of an IRouter packet (or other system controller data)
 * to the system controller.
 *
 */

static inline int

write_status_check(struct subch_data_s *sd, int count)
{
	return ia64_sn_irtr_send(sd->sd_nasid, sd->sd_subch, sd->sd_wb, count);
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 33 100.00% 1 100.00%
Total 33 100.00% 1 100.00%


static ssize_t

scdrv_write(struct file *file, const char __user *buf,
	    size_t count, loff_t *f_pos)
{
	unsigned long flags;
	int status;
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;

	/* try to get control of the write buffer */
	if (down_trylock(&sd->sd_wbs)) {
		/* somebody else has it now;
                 * if we're non-blocking, then exit...
                 */
		if (file->f_flags & O_NONBLOCK) {
			return -EAGAIN;
		}
		/* ...or if we want to block, then do so here */
		if (down_interruptible(&sd->sd_wbs)) {
			/* something went wrong with wait */
			return -ERESTARTSYS;
		}
	}

	count = min((int) count, CHUNKSIZE);
	if (copy_from_user(sd->sd_wb, buf, count)) {
		up(&sd->sd_wbs);
		return -EFAULT;
	}

	/* try to send the buffer */
	spin_lock_irqsave(&sd->sd_wlock, flags);
	status = write_status_check(sd, count);

	/* if we failed, and we want to block, then loop */
	while (status <= 0) {
		DECLARE_WAITQUEUE(wait, current);

		if (file->f_flags & O_NONBLOCK) {
			spin_unlock_irqrestore(&sd->sd_wlock, flags);
			up(&sd->sd_wbs);
			return -EAGAIN;
		}

		set_current_state(TASK_INTERRUPTIBLE);
		add_wait_queue(&sd->sd_wq, &wait);
		spin_unlock_irqrestore(&sd->sd_wlock, flags);

		schedule_timeout(msecs_to_jiffies(SCDRV_TIMEOUT));

		remove_wait_queue(&sd->sd_wq, &wait);
		if (signal_pending(current)) {
			/* wait was interrupted */
			up(&sd->sd_wbs);
			return -ERESTARTSYS;
		}

		spin_lock_irqsave(&sd->sd_wlock, flags);
		status = write_status_check(sd, count);
	}
	spin_unlock_irqrestore(&sd->sd_wlock, flags);

	/* release the write buffer and wake anyone who's waiting for it */
	up(&sd->sd_wbs);

	/* return the number of characters accepted (should be the complete
         * "chunk" as requested)
         */
	if ((status >= 0) && (status < count)) {
		pr_debug("Didn't accept the full chunk; %d of %d\n",
			 status, (int) count);
	}
	return status;
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 324 96.72% 1 25.00%
domen puncer domen puncer 5 1.49% 1 25.00%
nicholas mc guire nicholas mc guire 3 0.90% 1 25.00%
dan carpenter dan carpenter 3 0.90% 1 25.00%
Total 335 100.00% 4 100.00%


static unsigned int

scdrv_poll(struct file *file, struct poll_table_struct *wait)
{
	unsigned int mask = 0;
	int status = 0;
	struct subch_data_s *sd = (struct subch_data_s *) file->private_data;
	unsigned long flags;

	poll_wait(file, &sd->sd_rq, wait);
	poll_wait(file, &sd->sd_wq, wait);

	spin_lock_irqsave(&sd->sd_rlock, flags);
	spin_lock(&sd->sd_wlock);
	status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);
	spin_unlock(&sd->sd_wlock);
	spin_unlock_irqrestore(&sd->sd_rlock, flags);

	if (status > 0) {
		if (status & SAL_IROUTER_INTR_RECV) {
			mask |= POLLIN | POLLRDNORM;
		}
		if (status & SAL_IROUTER_INTR_XMIT) {
			mask |= POLLOUT | POLLWRNORM;
		}
	}

	return mask;
}

Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 158 100.00% 1 100.00%
Total 158 100.00% 1 100.00%


static const struct file_operations scdrv_fops = {
	.owner =	THIS_MODULE,
	.read =		scdrv_read,
	.write =	scdrv_write,
	.poll =		scdrv_poll,
	.open =		scdrv_open,
	.release =	scdrv_release,
	.llseek =	noop_llseek,
};


static struct class *snsc_class;

/*
 * scdrv_init
 *
 * Called at boot time to initialize the system controller communication
 * facility.
 */

int __init

scdrv_init(void)
{
	geoid_t geoid;
	cnodeid_t cnode;
	char devname[32];
	char *devnamep;
	struct sysctl_data_s *scd;
	void *salbuf;
	dev_t first_dev, dev;
	nasid_t event_nasid;

	if (!ia64_platform_is("sn2"))
		return -ENODEV;

	event_nasid = ia64_sn_get_console_nasid();

	snsc_class = class_create(THIS_MODULE, SYSCTL_BASENAME);
	if (IS_ERR(snsc_class)) {
		printk("%s: failed to allocate class\n", __func__);
		return PTR_ERR(snsc_class);
	}

	if (alloc_chrdev_region(&first_dev, 0, num_cnodes,
				SYSCTL_BASENAME) < 0) {
		printk("%s: failed to register SN system controller device\n",
		       __func__);
		return -ENODEV;
	}

	for (cnode = 0; cnode < num_cnodes; cnode++) {
			geoid = cnodeid_get_geoid(cnode);
			devnamep = devname;
			format_module_id(devnamep, geo_module(geoid),
					 MODULE_FORMAT_BRIEF);
			devnamep = devname + strlen(devname);
			sprintf(devnamep, "^%d#%d", geo_slot(geoid),
				geo_slab(geoid));

			/* allocate sysctl device data */
			scd = kzalloc(sizeof (struct sysctl_data_s),
				      GFP_KERNEL);
			if (!scd) {
				printk("%s: failed to allocate device info"
				       "for %s/%s\n", __func__,
				       SYSCTL_BASENAME, devname);
				continue;
			}

			/* initialize sysctl device data fields */
			scd->scd_nasid = cnodeid_to_nasid(cnode);
			if (!(salbuf = kmalloc(SCDRV_BUFSZ, GFP_KERNEL))) {
				printk("%s: failed to allocate driver buffer"
				       "(%s%s)\n", __func__,
				       SYSCTL_BASENAME, devname);
				kfree(scd);
				continue;
			}

			if (ia64_sn_irtr_init(scd->scd_nasid, salbuf,
					      SCDRV_BUFSZ) < 0) {
				printk
				    ("%s: failed to initialize SAL for"
				     " system controller communication"
				     " (%s/%s): outdated PROM?\n",
				     __func__, SYSCTL_BASENAME, devname);
				kfree(scd);
				kfree(salbuf);
				continue;
			}

			dev = first_dev + cnode;
			cdev_init(&scd->scd_cdev, &scdrv_fops);
			if (cdev_add(&scd->scd_cdev, dev, 1)) {
				printk("%s: failed to register system"
				       " controller device (%s%s)\n",
				       __func__, SYSCTL_BASENAME, devname);
				kfree(scd);
				kfree(salbuf);
				continue;
			}

			device_create(snsc_class, NULL, dev, NULL,
				      "%s", devname);

			ia64_sn_irtr_intr_enable(scd->scd_nasid,
						 0 /*ignored */ ,
						 SAL_IROUTER_INTR_RECV);

                        /* on the console nasid, prepare to receive
                         * system controller environmental events
                         */
                        if(scd->scd_nasid == event_nasid) {
                                scdrv_event_init(scd);
                        }
	}
	return 0;
}
Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 326 80.89% 2 16.67%
zhouyi zhou zhouyi zhou 31 7.69% 1 8.33%
greg edwards greg edwards 16 3.97% 1 8.33%
patrick gefre patrick gefre 11 2.73% 1 8.33%
andrew morton andrew morton 6 1.49% 1 8.33%
greg kroah-hartman greg kroah-hartman 5 1.24% 3 25.00%
harvey harrison harvey harrison 5 1.24% 1 8.33%
jack steiner jack steiner 2 0.50% 1 8.33%
jes sorensen jes sorensen 1 0.25% 1 8.33%
Total 403 100.00% 12 100.00%


device_initcall(scdrv_init);
Overall Contributors
Person Tokens Prop Commits CommitProp
greg howard greg howard 1717 91.82% 2 8.70%
zhouyi zhou zhouyi zhou 31 1.66% 1 4.35%
arnd bergmann arnd bergmann 27 1.44% 2 8.70%
patrick gefre patrick gefre 17 0.91% 1 4.35%
greg edwards greg edwards 16 0.86% 1 4.35%
greg kroah-hartman greg kroah-hartman 11 0.59% 4 17.39%
domen puncer domen puncer 10 0.53% 1 4.35%
harvey harrison harvey harrison 9 0.48% 1 4.35%
andrew morton andrew morton 6 0.32% 1 4.35%
nicholas mc guire nicholas mc guire 6 0.32% 1 4.35%
jonathan corbet jonathan corbet 5 0.27% 1 4.35%
jes sorensen jes sorensen 3 0.16% 1 4.35%
dan carpenter dan carpenter 3 0.16% 1 4.35%
jesse barnes jesse barnes 3 0.16% 1 4.35%
jack steiner jack steiner 2 0.11% 1 4.35%
paul gortmaker paul gortmaker 2 0.11% 1 4.35%
arjan van de ven arjan van de ven 1 0.05% 1 4.35%
thomas gleixner thomas gleixner 1 0.05% 1 4.35%
Total 1870 100.00% 23 100.00%
Directory: drivers/char

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
	Person	Tokens	Prop	Commits	CommitProp
greg howard	greg howard	132	100.00%	1	100.00%
	Total	132	100.00%	1	100.00%
cregit-Linux how code gets into the kernel

Release 4.10 drivers/char/snsc.c

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Overall Contributors
