patch-2.4.22 linux-2.4.22/drivers/sgi/char/usema.c

• Lines: 185
• Date: 1969-12-31 16:00:00.000000000 -0800
• Orig file: linux-2.4.21/drivers/sgi/char/usema.c
• Orig date: 2002-11-28 15:53:14.000000000 -0800

diff -urN linux-2.4.21/drivers/sgi/char/usema.c linux-2.4.22/drivers/sgi/char/usema.c
@@ -1,184 +0,0 @@
-/*
- * usema.c: software semaphore driver (see IRIX's usema(7M))
- * written 1997 Mike Shaver (shaver@neon.ingenia.ca)
- *         1997 Miguel de Icaza (miguel@kernel.org)
- *
- * This file contains the implementation of /dev/usemaclone,
- * the devices used by IRIX's us* semaphore routines.
- *
- * /dev/usemaclone is used to create a new semaphore device, and then
- * the semaphore is manipulated via ioctls.
- *
- * At least for the zero-contention case, lock set and unset as well
- * as semaphore P and V are done in userland, which makes things a
- * little bit better.  I suspect that the ioctls are used to register
- * the process as blocking, etc.
- *
- * Much inspiration and structure stolen from Miguel's shmiq work.
- *
- * For more information:
- * usema(7m), usinit(3p), usnewsema(3p)
- * /usr/include/sys/usioctl.h
- *
- */
-#include <linux/fs.h>
-#include <linux/miscdevice.h>
-#include <linux/sched.h>
-#include <linux/file.h>
-#include <linux/major.h>
-#include <linux/poll.h>
-#include <linux/string.h>
-#include <linux/dcache.h>
-#include <linux/mm.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/smp_lock.h>
-#include "usema.h"
-
-#include <asm/usioctl.h>
-#include <asm/mman.h>
-#include <asm/uaccess.h>
-
-struct irix_usema {
-	struct file *filp;
-	wait_queue_head_t proc_list;
-};
-
-
-static int
-sgi_usema_attach (usattach_t * attach, struct irix_usema *usema)
-{
-	int newfd;
-	newfd = get_unused_fd();
-	if (newfd < 0)
-		return newfd;
-
-	get_file(usema->filp);
-	fd_install(newfd, usema->filp);
-	/* Is that it? */
-	printk("UIOCATTACHSEMA: new usema fd is %d", newfd);
-	return newfd;
-}
-
-static int
-sgi_usemaclone_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
-		unsigned long arg)
-{
-	struct irix_usema *usema = file->private_data;
-	int retval;
-
-	printk("[%s:%d] wants ioctl 0x%xd (arg 0x%lx)",
-	       current->comm, current->pid, cmd, arg);
-
-	switch(cmd) {
-	case UIOCATTACHSEMA: {
-		/* They pass us information about the semaphore to
-		   which they wish to be attached, and we create&return
-		   a new fd corresponding to the appropriate semaphore.
-		   */
-		usattach_t *attach = (usattach_t *)arg;
-		retval = verify_area(VERIFY_READ, attach, sizeof(usattach_t));
-		if (retval) {
-			printk("[%s:%d] sgi_usema_ioctl(UIOCATTACHSEMA): "
-			       "verify_area failure",
-			       current->comm, current->pid);
-			return retval;
-		}
-		if (usema == 0)
-			return -EINVAL;
-
-		printk("UIOCATTACHSEMA: attaching usema %p to process %d\n",
-		       usema, current->pid);
-		/* XXX what is attach->us_handle for? */
-		return sgi_usema_attach(attach, usema);
-		break;
-	}
-	case UIOCABLOCK:	/* XXX make `async' */
-	case UIOCNOIBLOCK:	/* XXX maybe? */
-	case UIOCBLOCK: {
-		/* Block this process on the semaphore */
-		usattach_t *attach = (usattach_t *)arg;
-
-		retval = verify_area(VERIFY_READ, attach, sizeof(usattach_t));
-		if (retval) {
-			printk("[%s:%d] sgi_usema_ioctl(UIOC*BLOCK): "
-			       "verify_area failure",
-			       current->comm, current->pid);
-			return retval;
-		}
-		printk("UIOC*BLOCK: putting process %d to sleep on usema %p",
-		       current->pid, usema);
-		if (cmd == UIOCNOIBLOCK)
-			interruptible_sleep_on(&usema->proc_list);
-		else
-			sleep_on(&usema->proc_list);
-		return 0;
-	}
-	case UIOCAUNBLOCK:	/* XXX make `async' */
-	case UIOCUNBLOCK: {
-		/* Wake up all process waiting on this semaphore */
-		usattach_t *attach = (usattach_t *)arg;
-
-		retval = verify_area(VERIFY_READ, attach, sizeof(usattach_t));
-		if (retval) {
-			printk("[%s:%d] sgi_usema_ioctl(UIOC*BLOCK): "
-			       "verify_area failure",
-			       current->comm, current->pid);
-			return retval;
-		}
-
-		printk("[%s:%d] releasing usema %p",
-		       current->comm, current->pid, usema);
-		wake_up(&usema->proc_list);
-		return 0;
-	}
-	}
-	return -ENOSYS;
-}
-
-static unsigned int
-sgi_usemaclone_poll(struct file *filp, poll_table *wait)
-{
-	struct irix_usema *usema = filp->private_data;
-
-	printk("[%s:%d] wants to poll usema %p",
-	       current->comm, current->pid, usema);
-
-	return 0;
-}
-
-static int
-sgi_usemaclone_open(struct inode *inode, struct file *filp)
-{
-	struct irix_usema *usema;
-
-	usema = kmalloc (sizeof (struct irix_usema), GFP_KERNEL);
-	if (!usema)
-		return -ENOMEM;
-
-	usema->filp        = filp;
-	init_waitqueue_head(&usema->proc_list);
-	filp->private_data = usema;
-
-	return 0;
-}
-
-struct file_operations sgi_usemaclone_fops = {
-	poll:		sgi_usemaclone_poll,
-	ioctl:		sgi_usemaclone_ioctl,
-	open:		sgi_usemaclone_open,
-};
-
-static struct miscdevice dev_usemaclone = {
-	SGI_USEMACLONE, "usemaclone", &sgi_usemaclone_fops
-};
-
-void
-usema_init(void)
-{
-	printk("usemaclone misc device registered (minor: %d)\n",
-	       SGI_USEMACLONE);
-	misc_register(&dev_usemaclone);
-}
-
-EXPORT_SYMBOL(usema_init);