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[/] [test_project/] [trunk/] [linux_sd_driver/] [drivers/] [char/] [snsc.c] - Blame information for rev 65

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/*
 * 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/module.h>
#include <linux/slab.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 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;
}
 
/*
 * 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",
                       __FUNCTION__);
                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", __FUNCTION__);
                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 */
        rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt,
                         IRQF_SHARED | IRQF_DISABLED,
                         SYSCTL_BASENAME, sd);
        if (rv) {
                ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);
                kfree(sd);
                printk("%s: irq request failed (%d)\n", __FUNCTION__, rv);
                return -EBUSY;
        }
 
        return 0;
}
 
/*
 * 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;
}
 
/*
 * 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);
}
 
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(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",
                                 __FUNCTION__, (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;
}
 
/*
 * 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);
}
 
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(&sd->sd_wlock);
                        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(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;
}
 
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;
}
 
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,
};
 
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();
 
        if (alloc_chrdev_region(&first_dev, 0, num_cnodes,
                                SYSCTL_BASENAME) < 0) {
                printk("%s: failed to register SN system controller device\n",
                       __FUNCTION__);
                return -ENODEV;
        }
        snsc_class = class_create(THIS_MODULE, SYSCTL_BASENAME);
 
        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", __FUNCTION__,
                                       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", __FUNCTION__,
                                       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",
                                     __FUNCTION__, 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",
                                       __FUNCTION__, SYSCTL_BASENAME, devname);
                                kfree(scd);
                                kfree(salbuf);
                                continue;
                        }
 
                        device_create(snsc_class, NULL, dev, "%s", devname);
 
                        ia64_sn_irtr_intr_enable(scd->scd_nasid,
 
                                                 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;
}
 
module_init(scdrv_init);

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[/] [test_project/] [trunk/] [linux_sd_driver/] [drivers/] [char/] [snsc.c] - Blame information for rev 65

Line No.	Rev	Author	Line
1	62	marcus.erl	`/*`
2			`* SN Platform system controller communication support`
3			`*`
4			`* This file is subject to the terms and conditions of the GNU General Public`
5			`* License. See the file "COPYING" in the main directory of this archive`
6			`* for more details.`
7			`*`
8			`* Copyright (C) 2004, 2006 Silicon Graphics, Inc. All rights reserved.`
9			`*/`
10
11			`/*`
12			`* System controller communication driver`
13			`*`
14			`* This driver allows a user process to communicate with the system`
15			`* controller (a.k.a. "IRouter") network in an SGI SN system.`
16			`*/`
17
18			`#include <linux/interrupt.h>`
19			`#include <linux/sched.h>`
20			`#include <linux/device.h>`
21			`#include <linux/poll.h>`
22			`#include <linux/module.h>`
23			`#include <linux/slab.h>`
24			`#include <asm/sn/io.h>`
25			`#include <asm/sn/sn_sal.h>`
26			`#include <asm/sn/module.h>`
27			`#include <asm/sn/geo.h>`
28			`#include <asm/sn/nodepda.h>`
29			`#include "snsc.h"`
30
31			`#define SYSCTL_BASENAME "snsc"`
32
33			`#define SCDRV_BUFSZ 2048`
34			`#define SCDRV_TIMEOUT 1000`
35
36			`static irqreturn_t`
37			`scdrv_interrupt(int irq, void *subch_data)`
38			`{`
39			`struct subch_data_s *sd = subch_data;`
40			`unsigned long flags;`
41			`int status;`
42
43			`spin_lock_irqsave(&sd->sd_rlock, flags);`
44			`spin_lock(&sd->sd_wlock);`
45			`status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);`
46
47			`if (status > 0) {`
48			`if (status & SAL_IROUTER_INTR_RECV) {`
49			`wake_up(&sd->sd_rq);`
50			`}`
51			`if (status & SAL_IROUTER_INTR_XMIT) {`
52			`ia64_sn_irtr_intr_disable`
53			`(sd->sd_nasid, sd->sd_subch,`
54			`SAL_IROUTER_INTR_XMIT);`
55			`wake_up(&sd->sd_wq);`
56			`}`
57			`}`
58			`spin_unlock(&sd->sd_wlock);`
59			`spin_unlock_irqrestore(&sd->sd_rlock, flags);`
60			`return IRQ_HANDLED;`
61			`}`
62
63			`/*`
64			`* scdrv_open`
65			`*`
66			`* Reserve a subchannel for system controller communication.`
67			`*/`
68
69			`static int`
70			`scdrv_open(struct inode inode, struct file file)`
71			`{`
72			`struct sysctl_data_s *scd;`
73			`struct subch_data_s *sd;`
74			`int rv;`
75
76			`/* look up device info for this device file */`
77			`scd = container_of(inode->i_cdev, struct sysctl_data_s, scd_cdev);`
78
79			`/* allocate memory for subchannel data */`
80			`sd = kzalloc(sizeof (struct subch_data_s), GFP_KERNEL);`
81			`if (sd == NULL) {`
82			`printk("%s: couldn't allocate subchannel data\n",`
83			`__FUNCTION__);`
84			`return -ENOMEM;`
85			`}`
86
87			`/* initialize subch_data_s fields */`
88			`sd->sd_nasid = scd->scd_nasid;`
89			`sd->sd_subch = ia64_sn_irtr_open(scd->scd_nasid);`
90
91			`if (sd->sd_subch < 0) {`
92			`kfree(sd);`
93			`printk("%s: couldn't allocate subchannel\n", __FUNCTION__);`
94			`return -EBUSY;`
95			`}`
96
97			`spin_lock_init(&sd->sd_rlock);`
98			`spin_lock_init(&sd->sd_wlock);`
99			`init_waitqueue_head(&sd->sd_rq);`
100			`init_waitqueue_head(&sd->sd_wq);`
101			`sema_init(&sd->sd_rbs, 1);`
102			`sema_init(&sd->sd_wbs, 1);`
103
104			`file->private_data = sd;`
105
106			`/* hook this subchannel up to the system controller interrupt */`
107			`rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt,`
108			`IRQF_SHARED \| IRQF_DISABLED,`
109			`SYSCTL_BASENAME, sd);`
110			`if (rv) {`
111			`ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);`
112			`kfree(sd);`
113			`printk("%s: irq request failed (%d)\n", __FUNCTION__, rv);`
114			`return -EBUSY;`
115			`}`
116
117			`return 0;`
118			`}`
119
120			`/*`
121			`* scdrv_release`
122			`*`
123			`* Release a previously-reserved subchannel.`
124			`*/`
125
126			`static int`
127			`scdrv_release(struct inode inode, struct file file)`
128			`{`
129			`struct subch_data_s sd = (struct subch_data_s ) file->private_data;`
130			`int rv;`
131
132			`/* free the interrupt */`
133			`free_irq(SGI_UART_VECTOR, sd);`
134
135			`/* ask SAL to close the subchannel */`
136			`rv = ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);`
137
138			`kfree(sd);`
139			`return rv;`
140			`}`
141
142			`/*`
143			`* scdrv_read`
144			`*`
145			`* Called to read bytes from the open IRouter pipe.`
146			`*`
147			`*/`
148
149			`static inline int`
150			`read_status_check(struct subch_data_s sd, int len)`
151			`{`
152			`return ia64_sn_irtr_recv(sd->sd_nasid, sd->sd_subch, sd->sd_rb, len);`
153			`}`
154
155			`static ssize_t`
156			`scdrv_read(struct file file, char __user buf, size_t count, loff_t *f_pos)`
157			`{`
158			`int status;`
159			`int len;`
160			`unsigned long flags;`
161			`struct subch_data_s sd = (struct subch_data_s ) file->private_data;`
162
163			`/* try to get control of the read buffer */`
164			`if (down_trylock(&sd->sd_rbs)) {`
165			`/* somebody else has it now;`
166			`* if we're non-blocking, then exit...`
167			`*/`
168			`if (file->f_flags & O_NONBLOCK) {`
169			`return -EAGAIN;`
170			`}`
171			`/* ...or if we want to block, then do so here */`
172			`if (down_interruptible(&sd->sd_rbs)) {`
173			`/* something went wrong with wait */`
174			`return -ERESTARTSYS;`
175			`}`
176			`}`
177
178			`/* anything to read? */`
179			`len = CHUNKSIZE;`
180			`spin_lock_irqsave(&sd->sd_rlock, flags);`
181			`status = read_status_check(sd, &len);`
182
183			`/* if not, and we're blocking I/O, loop */`
184			`while (status < 0) {`
185			`DECLARE_WAITQUEUE(wait, current);`
186
187			`if (file->f_flags & O_NONBLOCK) {`
188			`spin_unlock_irqrestore(&sd->sd_rlock, flags);`
189			`up(&sd->sd_rbs);`
190			`return -EAGAIN;`
191			`}`
192
193			`len = CHUNKSIZE;`
194			`set_current_state(TASK_INTERRUPTIBLE);`
195			`add_wait_queue(&sd->sd_rq, &wait);`
196			`spin_unlock_irqrestore(&sd->sd_rlock, flags);`
197
198			`schedule_timeout(SCDRV_TIMEOUT);`
199
200			`remove_wait_queue(&sd->sd_rq, &wait);`
201			`if (signal_pending(current)) {`
202			`/* wait was interrupted */`
203			`up(&sd->sd_rbs);`
204			`return -ERESTARTSYS;`
205			`}`
206
207			`spin_lock_irqsave(&sd->sd_rlock, flags);`
208			`status = read_status_check(sd, &len);`
209			`}`
210			`spin_unlock_irqrestore(&sd->sd_rlock, flags);`
211
212			`if (len > 0) {`
213			`/* we read something in the last read_status_check(); copy`
214			`* it out to user space`
215			`*/`
216			`if (count < len) {`
217			`pr_debug("%s: only accepting %d of %d bytes\n",`
218			`__FUNCTION__, (int) count, len);`
219			`}`
220			`len = min((int) count, len);`
221			`if (copy_to_user(buf, sd->sd_rb, len))`
222			`len = -EFAULT;`
223			`}`
224
225			`/* release the read buffer and wake anyone who might be`
226			`* waiting for it`
227			`*/`
228			`up(&sd->sd_rbs);`
229
230			`/* return the number of characters read in */`
231			`return len;`
232			`}`
233
234			`/*`
235			`* scdrv_write`
236			`*`
237			`* Writes a chunk of an IRouter packet (or other system controller data)`
238			`* to the system controller.`
239			`*`
240			`*/`
241			`static inline int`
242			`write_status_check(struct subch_data_s *sd, int count)`
243			`{`
244			`return ia64_sn_irtr_send(sd->sd_nasid, sd->sd_subch, sd->sd_wb, count);`
245			`}`
246
247			`static ssize_t`
248			`scdrv_write(struct file file, const char __user buf,`
249			`size_t count, loff_t *f_pos)`
250			`{`
251			`unsigned long flags;`
252			`int status;`
253			`struct subch_data_s sd = (struct subch_data_s ) file->private_data;`
254
255			`/* try to get control of the write buffer */`
256			`if (down_trylock(&sd->sd_wbs)) {`
257			`/* somebody else has it now;`
258			`* if we're non-blocking, then exit...`
259			`*/`
260			`if (file->f_flags & O_NONBLOCK) {`
261			`return -EAGAIN;`
262			`}`
263			`/* ...or if we want to block, then do so here */`
264			`if (down_interruptible(&sd->sd_wbs)) {`
265			`/* something went wrong with wait */`
266			`return -ERESTARTSYS;`
267			`}`
268			`}`
269
270			`count = min((int) count, CHUNKSIZE);`
271			`if (copy_from_user(sd->sd_wb, buf, count)) {`
272			`up(&sd->sd_wbs);`
273			`return -EFAULT;`
274			`}`
275
276			`/* try to send the buffer */`
277			`spin_lock_irqsave(&sd->sd_wlock, flags);`
278			`status = write_status_check(sd, count);`
279
280			`/* if we failed, and we want to block, then loop */`
281			`while (status <= 0) {`
282			`DECLARE_WAITQUEUE(wait, current);`
283
284			`if (file->f_flags & O_NONBLOCK) {`
285			`spin_unlock(&sd->sd_wlock);`
286			`up(&sd->sd_wbs);`
287			`return -EAGAIN;`
288			`}`
289
290			`set_current_state(TASK_INTERRUPTIBLE);`
291			`add_wait_queue(&sd->sd_wq, &wait);`
292			`spin_unlock_irqrestore(&sd->sd_wlock, flags);`
293
294			`schedule_timeout(SCDRV_TIMEOUT);`
295
296			`remove_wait_queue(&sd->sd_wq, &wait);`
297			`if (signal_pending(current)) {`
298			`/* wait was interrupted */`
299			`up(&sd->sd_wbs);`
300			`return -ERESTARTSYS;`
301			`}`
302
303			`spin_lock_irqsave(&sd->sd_wlock, flags);`
304			`status = write_status_check(sd, count);`
305			`}`
306			`spin_unlock_irqrestore(&sd->sd_wlock, flags);`
307
308			`/* release the write buffer and wake anyone who's waiting for it */`
309			`up(&sd->sd_wbs);`
310
311			`/* return the number of characters accepted (should be the complete`
312			`* "chunk" as requested)`
313			`*/`
314			`if ((status >= 0) && (status < count)) {`
315			`pr_debug("Didn't accept the full chunk; %d of %d\n",`
316			`status, (int) count);`
317			`}`
318			`return status;`
319			`}`
320
321			`static unsigned int`
322			`scdrv_poll(struct file file, struct poll_table_struct wait)`
323			`{`
324			`unsigned int mask = 0;`
325			`int status = 0;`
326			`struct subch_data_s sd = (struct subch_data_s ) file->private_data;`
327			`unsigned long flags;`
328
329			`poll_wait(file, &sd->sd_rq, wait);`
330			`poll_wait(file, &sd->sd_wq, wait);`
331
332			`spin_lock_irqsave(&sd->sd_rlock, flags);`
333			`spin_lock(&sd->sd_wlock);`
334			`status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);`
335			`spin_unlock(&sd->sd_wlock);`
336			`spin_unlock_irqrestore(&sd->sd_rlock, flags);`
337
338			`if (status > 0) {`
339			`if (status & SAL_IROUTER_INTR_RECV) {`
340			`mask \|= POLLIN \| POLLRDNORM;`
341			`}`
342			`if (status & SAL_IROUTER_INTR_XMIT) {`
343			`mask \|= POLLOUT \| POLLWRNORM;`
344			`}`
345			`}`
346
347			`return mask;`
348			`}`
349
350			`static const struct file_operations scdrv_fops = {`
351			`.owner = THIS_MODULE,`
352			`.read = scdrv_read,`
353			`.write = scdrv_write,`
354			`.poll = scdrv_poll,`
355			`.open = scdrv_open,`
356			`.release = scdrv_release,`
357			`};`
358
359			`static struct class *snsc_class;`
360
361			`/*`
362			`* scdrv_init`
363			`*`
364			`* Called at boot time to initialize the system controller communication`
365			`* facility.`
366			`*/`
367			`int __init`
368			`scdrv_init(void)`
369			`{`
370			`geoid_t geoid;`
371			`cnodeid_t cnode;`
372			`char devname[32];`
373			`char *devnamep;`
374			`struct sysctl_data_s *scd;`
375			`void *salbuf;`
376			`dev_t first_dev, dev;`
377			`nasid_t event_nasid;`
378
379			`if (!ia64_platform_is("sn2"))`
380			`return -ENODEV;`
381
382			`event_nasid = ia64_sn_get_console_nasid();`
383
384			`if (alloc_chrdev_region(&first_dev, 0, num_cnodes,`
385			`SYSCTL_BASENAME) < 0) {`
386			`printk("%s: failed to register SN system controller device\n",`
387			`__FUNCTION__);`
388			`return -ENODEV;`
389			`}`
390			`snsc_class = class_create(THIS_MODULE, SYSCTL_BASENAME);`
391
392			`for (cnode = 0; cnode < num_cnodes; cnode++) {`
393			`geoid = cnodeid_get_geoid(cnode);`
394			`devnamep = devname;`
395			`format_module_id(devnamep, geo_module(geoid),`
396			`MODULE_FORMAT_BRIEF);`
397			`devnamep = devname + strlen(devname);`
398			`sprintf(devnamep, "^%d#%d", geo_slot(geoid),`
399			`geo_slab(geoid));`
400
401			`/* allocate sysctl device data */`
402			`scd = kzalloc(sizeof (struct sysctl_data_s),`
403			`GFP_KERNEL);`
404			`if (!scd) {`
405			`printk("%s: failed to allocate device info"`
406			`"for %s/%s\n", __FUNCTION__,`
407			`SYSCTL_BASENAME, devname);`
408			`continue;`
409			`}`
410
411			`/* initialize sysctl device data fields */`
412			`scd->scd_nasid = cnodeid_to_nasid(cnode);`
413			`if (!(salbuf = kmalloc(SCDRV_BUFSZ, GFP_KERNEL))) {`
414			`printk("%s: failed to allocate driver buffer"`
415			`"(%s%s)\n", __FUNCTION__,`
416			`SYSCTL_BASENAME, devname);`
417			`kfree(scd);`
418			`continue;`
419			`}`
420
421			`if (ia64_sn_irtr_init(scd->scd_nasid, salbuf,`
422			`SCDRV_BUFSZ) < 0) {`
423			`printk`
424			`("%s: failed to initialize SAL for"`
425			`" system controller communication"`
426			`" (%s/%s): outdated PROM?\n",`
427			`__FUNCTION__, SYSCTL_BASENAME, devname);`
428			`kfree(scd);`
429			`kfree(salbuf);`
430			`continue;`
431			`}`
432
433			`dev = first_dev + cnode;`
434			`cdev_init(&scd->scd_cdev, &scdrv_fops);`
435			`if (cdev_add(&scd->scd_cdev, dev, 1)) {`
436			`printk("%s: failed to register system"`
437			`" controller device (%s%s)\n",`
438			`__FUNCTION__, SYSCTL_BASENAME, devname);`
439			`kfree(scd);`
440			`kfree(salbuf);`
441			`continue;`
442			`}`
443
444			`device_create(snsc_class, NULL, dev, "%s", devname);`
445
446			`ia64_sn_irtr_intr_enable(scd->scd_nasid,`
447
448			`SAL_IROUTER_INTR_RECV);`
449
450			`/* on the console nasid, prepare to receive`
451			`* system controller environmental events`
452			`*/`
453			`if(scd->scd_nasid == event_nasid) {`
454			`scdrv_event_init(scd);`
455			`}`
456			`}`
457			`return 0;`
458			`}`
459
460			`module_init(scdrv_init);`