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	 99b7623380
			
		
	
	
		99b7623380
		
	
	
	
	
		
			
			Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy as correctly noted at bug #12454. Someone can lookup entry with NULL ->owner, thus not pinning enything, and release it later resulting in module refcount underflow. We can keep ->owner and supply it at registration time like ->proc_fops and ->data. But this leaves ->owner as easy-manipulative field (just one C assignment) and somebody will forget to unpin previous/pin current module when switching ->owner. ->proc_fops is declared as "const" which should give some thoughts. ->read_proc/->write_proc were just fixed to not require ->owner for protection. rmmod'ed directories will be empty and return "." and ".." -- no harm. And directories with tricky enough readdir and lookup shouldn't be modular. We definitely don't want such modular code. Removing ->owner will also make PDE smaller. So, let's nuke it. Kudos to Jeff Layton for reminding about this, let's say, oversight. http://bugzilla.kernel.org/show_bug.cgi?id=12454 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
		
			
				
	
	
		
			303 lines
		
	
	
		
			6.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			303 lines
		
	
	
		
			6.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| #ifdef CONFIG_PROC_FS
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| #include <linux/errno.h>
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| #include <linux/kernel.h>
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| #include <linux/string.h>
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| #include <linux/mm.h>
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| #include <linux/module.h>
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| #include <linux/proc_fs.h>
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| #include <linux/time.h>
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| #include <linux/seq_file.h>
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| #include <asm/uaccess.h>
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| #include <linux/atmmpc.h>
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| #include <linux/atm.h>
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| #include "mpc.h"
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| #include "mpoa_caches.h"
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| 
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| /*
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|  * mpoa_proc.c: Implementation MPOA client's proc
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|  * file system statistics
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|  */
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| 
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| #if 1
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| #define dprintk printk   /* debug */
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| #else
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| #define dprintk(format,args...)
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| #endif
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| 
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| #define STAT_FILE_NAME "mpc"     /* Our statistic file's name */
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| 
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| extern struct mpoa_client *mpcs;
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| extern struct proc_dir_entry *atm_proc_root;  /* from proc.c. */
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| 
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| static int proc_mpc_open(struct inode *inode, struct file *file);
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| static ssize_t proc_mpc_write(struct file *file, const char __user *buff,
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| 			      size_t nbytes, loff_t *ppos);
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| 
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| static int parse_qos(const char *buff);
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| 
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| /*
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|  *   Define allowed FILE OPERATIONS
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|  */
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| static const struct file_operations mpc_file_operations = {
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| 	.owner =	THIS_MODULE,
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| 	.open =		proc_mpc_open,
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| 	.read =		seq_read,
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| 	.llseek =	seq_lseek,
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| 	.write =	proc_mpc_write,
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| 	.release =	seq_release,
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| };
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| 
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| /*
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|  * Returns the state of an ingress cache entry as a string
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|  */
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| static const char *ingress_state_string(int state){
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| 	switch(state) {
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| 	case INGRESS_RESOLVING:
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| 		return "resolving  ";
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| 		break;
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| 	case INGRESS_RESOLVED:
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| 		return "resolved   ";
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| 		break;
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| 	case INGRESS_INVALID:
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| 		return "invalid    ";
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| 		break;
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| 	case INGRESS_REFRESHING:
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| 		return "refreshing ";
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| 		break;
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| 	default:
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| 	       return "";
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| 	}
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| }
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| 
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| /*
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|  * Returns the state of an egress cache entry as a string
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|  */
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| static const char *egress_state_string(int state){
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| 	switch(state) {
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| 	case EGRESS_RESOLVED:
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| 		return "resolved   ";
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| 		break;
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| 	case EGRESS_PURGE:
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| 		return "purge      ";
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| 		break;
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| 	case EGRESS_INVALID:
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| 		return "invalid    ";
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| 		break;
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| 	default:
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| 	       return "";
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| 	}
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| }
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| 
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| /*
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|  * FIXME: mpcs (and per-mpc lists) have no locking whatsoever.
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|  */
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| 
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| static void *mpc_start(struct seq_file *m, loff_t *pos)
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| {
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| 	loff_t l = *pos;
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| 	struct mpoa_client *mpc;
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| 
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| 	if (!l--)
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| 		return SEQ_START_TOKEN;
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| 	for (mpc = mpcs; mpc; mpc = mpc->next)
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| 		if (!l--)
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| 			return mpc;
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| 	return NULL;
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| }
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| 
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| static void *mpc_next(struct seq_file *m, void *v, loff_t *pos)
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| {
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| 	struct mpoa_client *p = v;
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| 	(*pos)++;
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| 	return v == SEQ_START_TOKEN ? mpcs : p->next;
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| }
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| 
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| static void mpc_stop(struct seq_file *m, void *v)
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| {
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| }
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| 
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| /*
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|  * READING function - called when the /proc/atm/mpoa file is read from.
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|  */
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| static int mpc_show(struct seq_file *m, void *v)
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| {
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| 	struct mpoa_client *mpc = v;
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| 	unsigned char *temp;
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| 	int i;
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| 	in_cache_entry *in_entry;
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| 	eg_cache_entry *eg_entry;
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| 	struct timeval now;
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| 	unsigned char ip_string[16];
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| 
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| 	if (v == SEQ_START_TOKEN) {
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| 		atm_mpoa_disp_qos(m);
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| 		return 0;
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| 	}
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| 
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| 	seq_printf(m, "\nInterface %d:\n\n", mpc->dev_num);
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| 	seq_printf(m, "Ingress Entries:\nIP address      State      Holding time  Packets fwded  VPI  VCI\n");
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| 	do_gettimeofday(&now);
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| 
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| 	for (in_entry = mpc->in_cache; in_entry; in_entry = in_entry->next) {
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| 		temp = (unsigned char *)&in_entry->ctrl_info.in_dst_ip;
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| 		sprintf(ip_string,"%d.%d.%d.%d", temp[0], temp[1], temp[2], temp[3]);
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| 		seq_printf(m, "%-16s%s%-14lu%-12u",
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| 			      ip_string,
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| 			      ingress_state_string(in_entry->entry_state),
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| 			      in_entry->ctrl_info.holding_time-(now.tv_sec-in_entry->tv.tv_sec),
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| 			      in_entry->packets_fwded);
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| 		if (in_entry->shortcut)
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| 			seq_printf(m, "   %-3d  %-3d",in_entry->shortcut->vpi,in_entry->shortcut->vci);
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| 		seq_printf(m, "\n");
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| 	}
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| 
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| 	seq_printf(m, "\n");
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| 	seq_printf(m, "Egress Entries:\nIngress MPC ATM addr\nCache-id        State      Holding time  Packets recvd  Latest IP addr   VPI VCI\n");
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| 	for (eg_entry = mpc->eg_cache; eg_entry; eg_entry = eg_entry->next) {
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| 		unsigned char *p = eg_entry->ctrl_info.in_MPC_data_ATM_addr;
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| 		for(i = 0; i < ATM_ESA_LEN; i++)
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| 			seq_printf(m, "%02x", p[i]);
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| 		seq_printf(m, "\n%-16lu%s%-14lu%-15u",
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| 			   (unsigned long)ntohl(eg_entry->ctrl_info.cache_id),
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| 			   egress_state_string(eg_entry->entry_state),
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| 			   (eg_entry->ctrl_info.holding_time-(now.tv_sec-eg_entry->tv.tv_sec)),
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| 			   eg_entry->packets_rcvd);
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| 
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| 		/* latest IP address */
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| 		temp = (unsigned char *)&eg_entry->latest_ip_addr;
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| 		sprintf(ip_string, "%d.%d.%d.%d", temp[0], temp[1], temp[2], temp[3]);
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| 		seq_printf(m, "%-16s", ip_string);
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| 
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| 		if (eg_entry->shortcut)
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| 			seq_printf(m, " %-3d %-3d",eg_entry->shortcut->vpi,eg_entry->shortcut->vci);
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| 		seq_printf(m, "\n");
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| 	}
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| 	seq_printf(m, "\n");
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| 	return 0;
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| }
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| 
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| static const struct seq_operations mpc_op = {
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| 	.start =	mpc_start,
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| 	.next =		mpc_next,
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| 	.stop =		mpc_stop,
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| 	.show =		mpc_show
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| };
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| 
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| static int proc_mpc_open(struct inode *inode, struct file *file)
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| {
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| 	return seq_open(file, &mpc_op);
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| }
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| 
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| static ssize_t proc_mpc_write(struct file *file, const char __user *buff,
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| 			      size_t nbytes, loff_t *ppos)
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| {
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| 	char *page, *p;
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| 	unsigned len;
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| 
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| 	if (nbytes == 0)
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| 		return 0;
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| 
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| 	if (nbytes >= PAGE_SIZE)
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| 		nbytes = PAGE_SIZE-1;
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| 
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| 	page = (char *)__get_free_page(GFP_KERNEL);
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| 	if (!page)
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| 		return -ENOMEM;
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| 
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| 	for (p = page, len = 0; len < nbytes; p++, len++) {
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| 		if (get_user(*p, buff++)) {
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| 			free_page((unsigned long)page);
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| 			return -EFAULT;
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| 		}
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| 		if (*p == '\0' || *p == '\n')
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| 			break;
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| 	}
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| 
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| 	*p = '\0';
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| 
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| 	if (!parse_qos(page))
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| 		printk("mpoa: proc_mpc_write: could not parse '%s'\n", page);
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| 
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| 	free_page((unsigned long)page);
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| 
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| 	return len;
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| }
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| 
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| static int parse_qos(const char *buff)
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| {
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| 	/* possible lines look like this
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| 	 * add 130.230.54.142 tx=max_pcr,max_sdu rx=max_pcr,max_sdu
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| 	 */
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| 	unsigned char ip[4];
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| 	int tx_pcr, tx_sdu, rx_pcr, rx_sdu;
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| 	__be32 ipaddr;
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| 	struct atm_qos qos;
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| 
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| 	memset(&qos, 0, sizeof(struct atm_qos));
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| 
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| 	if (sscanf(buff, "del %hhu.%hhu.%hhu.%hhu",
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| 			ip, ip+1, ip+2, ip+3) == 4) {
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| 		ipaddr = *(__be32 *)ip;
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| 		return atm_mpoa_delete_qos(atm_mpoa_search_qos(ipaddr));
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| 	}
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| 
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| 	if (sscanf(buff, "add %hhu.%hhu.%hhu.%hhu tx=%d,%d rx=tx",
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| 			ip, ip+1, ip+2, ip+3, &tx_pcr, &tx_sdu) == 6) {
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| 		rx_pcr = tx_pcr;
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| 		rx_sdu = tx_sdu;
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| 	} else if (sscanf(buff, "add %hhu.%hhu.%hhu.%hhu tx=%d,%d rx=%d,%d",
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| 		ip, ip+1, ip+2, ip+3, &tx_pcr, &tx_sdu, &rx_pcr, &rx_sdu) != 8)
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| 		return 0;
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| 
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| 	ipaddr = *(__be32 *)ip;
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| 	qos.txtp.traffic_class = ATM_CBR;
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| 	qos.txtp.max_pcr = tx_pcr;
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| 	qos.txtp.max_sdu = tx_sdu;
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| 	qos.rxtp.traffic_class = ATM_CBR;
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| 	qos.rxtp.max_pcr = rx_pcr;
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| 	qos.rxtp.max_sdu = rx_sdu;
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| 	qos.aal = ATM_AAL5;
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| 	dprintk("mpoa: mpoa_proc.c: parse_qos(): setting qos paramameters to tx=%d,%d rx=%d,%d\n",
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| 		qos.txtp.max_pcr,
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| 		qos.txtp.max_sdu,
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| 		qos.rxtp.max_pcr,
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| 		qos.rxtp.max_sdu
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| 		);
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| 
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| 	atm_mpoa_add_qos(ipaddr, &qos);
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| 	return 1;
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| }
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| 
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| /*
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|  * INITIALIZATION function - called when module is initialized/loaded.
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|  */
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| int mpc_proc_init(void)
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| {
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| 	struct proc_dir_entry *p;
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| 
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| 	p = proc_create(STAT_FILE_NAME, 0, atm_proc_root, &mpc_file_operations);
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| 	if (!p) {
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| 		printk(KERN_ERR "Unable to initialize /proc/atm/%s\n", STAT_FILE_NAME);
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| 		return -ENOMEM;
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| 	}
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| 	return 0;
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| }
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| 
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| /*
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|  * DELETING function - called when module is removed.
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|  */
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| void mpc_proc_clean(void)
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| {
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| 	remove_proc_entry(STAT_FILE_NAME,atm_proc_root);
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| }
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| 
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| 
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| #endif /* CONFIG_PROC_FS */
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| 
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| 
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| 
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| 
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| 
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| 
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