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