patch-2.4.21 linux-2.4.21/drivers/ide/raid/ataraid.c

• Lines: 318
• Date: 2003-06-13 07:51:34.000000000 -0700
• Orig file: linux-2.4.20/drivers/ide/raid/ataraid.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.20/drivers/ide/raid/ataraid.c linux-2.4.21/drivers/ide/raid/ataraid.c
@@ -0,0 +1,317 @@
+/*
+   ataraid.c  Copyright (C) 2001 Red Hat, Inc. All rights reserved.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+   
+   You should have received a copy of the GNU General Public License
+   (for example /usr/src/linux/COPYING); if not, write to the Free
+   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
+   
+   Authors: 	Arjan van de Ven <arjanv@redhat.com>
+   		
+   
+*/
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <asm/semaphore.h>
+#include <linux/sched.h>
+#include <linux/smp_lock.h>
+#include <linux/blkdev.h>
+#include <linux/blkpg.h>
+#include <linux/genhd.h>
+#include <linux/ioctl.h>
+#include <linux/kdev_t.h>
+#include <linux/swap.h>
+
+#include <linux/ide.h>
+#include <asm/uaccess.h>
+
+#include "ataraid.h"
+
+                                        
+static int ataraid_hardsect_size[256];
+static int ataraid_blksize_size[256];
+
+static struct raid_device_operations* ataraid_ops[16];
+
+static int ataraid_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
+static int ataraid_open(struct inode * inode, struct file * filp);
+static int ataraid_release(struct inode * inode, struct file * filp);
+static void ataraid_split_request(request_queue_t *q, int rw, struct buffer_head * bh);
+
+
+struct gendisk ataraid_gendisk;
+static int ataraid_gendisk_sizes[256];
+static int ataraid_readahead[256];
+
+static struct block_device_operations ataraid_fops = {
+	owner:			THIS_MODULE,
+	open:                   ataraid_open,
+	release:                ataraid_release,
+	ioctl:                  ataraid_ioctl,
+};
+                
+
+
+static DECLARE_MUTEX(ataraid_sem);
+
+/* Bitmap for the devices currently in use */
+static unsigned int ataraiduse;
+
+
+/* stub fops functions */
+
+static int ataraid_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)  
+{
+	int minor;
+	minor = MINOR(inode->i_rdev)>>SHIFT;
+	
+	if ((ataraid_ops[minor])&&(ataraid_ops[minor]->ioctl))
+		return (ataraid_ops[minor]->ioctl)(inode,file,cmd,arg);
+	return -EINVAL;
+}
+
+static int ataraid_open(struct inode * inode, struct file * filp)
+{
+	int minor;
+	minor = MINOR(inode->i_rdev)>>SHIFT;
+
+	if ((ataraid_ops[minor])&&(ataraid_ops[minor]->open))
+		return (ataraid_ops[minor]->open)(inode,filp);
+	return -EINVAL;
+}
+
+
+static int ataraid_release(struct inode * inode, struct file * filp)
+{
+	int minor;
+	minor = MINOR(inode->i_rdev)>>SHIFT;
+
+	if ((ataraid_ops[minor])&&(ataraid_ops[minor]->release))
+		return (ataraid_ops[minor]->release)(inode,filp);
+	return -EINVAL;
+}
+
+static int ataraid_make_request (request_queue_t *q, int rw, struct buffer_head * bh)
+{
+	int minor;
+	int retval;
+	minor = MINOR(bh->b_rdev)>>SHIFT;
+
+	if ((ataraid_ops[minor])&&(ataraid_ops[minor]->make_request)) {
+		
+		retval= (ataraid_ops[minor]->make_request)(q,rw,bh);
+		if (retval == -1) {
+			ataraid_split_request(q,rw,bh);		
+			return 0;
+		} else
+			return retval;
+	}
+	return -EINVAL;
+}
+
+struct buffer_head *ataraid_get_bhead(void)
+{
+	void *ptr = NULL;
+	while (!ptr) {
+		ptr=kmalloc(sizeof(struct buffer_head),GFP_NOIO);
+		if (!ptr) {
+			__set_current_state(TASK_RUNNING);
+			yield();
+		}
+	}
+	return ptr;
+}
+
+EXPORT_SYMBOL(ataraid_get_bhead);
+
+struct ataraid_bh_private *ataraid_get_private(void)
+{
+	void *ptr = NULL;
+	while (!ptr) {
+		ptr=kmalloc(sizeof(struct ataraid_bh_private),GFP_NOIO);
+		if (!ptr) {
+			__set_current_state(TASK_RUNNING);
+			yield();
+		}
+	}
+	return ptr;
+}
+
+EXPORT_SYMBOL(ataraid_get_private);
+
+void ataraid_end_request(struct buffer_head *bh, int uptodate)
+{
+	struct ataraid_bh_private *private = bh->b_private;
+
+	if (private==NULL)
+		BUG();
+
+	if (atomic_dec_and_test(&private->count)) {
+		private->parent->b_end_io(private->parent,uptodate);
+		private->parent = NULL;
+		kfree(private);
+	}
+	kfree(bh);
+}
+
+EXPORT_SYMBOL(ataraid_end_request);
+
+static void ataraid_split_request(request_queue_t *q, int rw, struct buffer_head * bh)
+{
+	struct buffer_head *bh1,*bh2;
+	struct ataraid_bh_private *private;
+	bh1=ataraid_get_bhead();
+	bh2=ataraid_get_bhead();
+
+	/* If either of those ever fails we're doomed */
+	if ((!bh1)||(!bh2))
+		BUG();
+	private = ataraid_get_private();
+	if (private==NULL)
+		BUG();
+	
+	memcpy(bh1, bh, sizeof(*bh));
+	memcpy(bh2, bh, sizeof(*bh));
+	
+	bh1->b_end_io = ataraid_end_request;
+	bh2->b_end_io = ataraid_end_request;
+
+	bh2->b_rsector += bh->b_size >> 10;
+	bh1->b_size /= 2;
+	bh2->b_size /= 2;
+	private->parent = bh;
+
+	bh1->b_private = private;
+	bh2->b_private = private;
+	atomic_set(&private->count,2);
+
+	bh2->b_data +=  bh->b_size/2;
+
+	generic_make_request(rw,bh1);
+	generic_make_request(rw,bh2);
+}
+
+
+
+
+/* device register / release functions */
+
+
+int ataraid_get_device(struct raid_device_operations *fops)
+{
+	int bit;
+	down(&ataraid_sem);
+	if (ataraiduse==~0U) {
+		up(&ataraid_sem);
+		return -ENODEV;
+	}
+	bit=ffz(ataraiduse); 
+	ataraiduse |= 1<<bit;
+	ataraid_ops[bit] = fops;
+	up(&ataraid_sem);
+	return bit;
+}
+
+void ataraid_release_device(int device)
+{
+	down(&ataraid_sem);
+	
+	if ((ataraiduse & (1<<device))==0)
+		BUG();	/* device wasn't registered at all */
+	
+	ataraiduse &= ~(1<<device);
+	ataraid_ops[device] = NULL;
+	up(&ataraid_sem);
+}
+
+void ataraid_register_disk(int device,long size)
+{
+	register_disk(&ataraid_gendisk, MKDEV(ATAMAJOR,16*device),16,
+		&ataraid_fops,size);
+
+}
+
+static __init int ataraid_init(void) 
+{
+	int i;
+        for(i=0;i<256;i++)
+	{
+        	ataraid_hardsect_size[i] = 512;
+		ataraid_blksize_size[i] = 1024;  
+		ataraid_readahead[i] = 1023;
+	}
+	
+	if (blksize_size[ATAMAJOR]==NULL)
+		blksize_size[ATAMAJOR] = ataraid_blksize_size;
+	if (hardsect_size[ATAMAJOR]==NULL)
+		hardsect_size[ATAMAJOR] = ataraid_hardsect_size;
+	
+	
+	/* setup the gendisk structure */	
+	ataraid_gendisk.part = kmalloc(256 * sizeof(struct hd_struct),GFP_KERNEL);
+	if (ataraid_gendisk.part==NULL) {
+		printk(KERN_ERR "ataraid: Couldn't allocate memory, aborting \n");
+		return -1;
+	}
+	
+	memset(&ataraid_gendisk.part[0],0,256*sizeof(struct hd_struct));
+	
+	
+	ataraid_gendisk.major       = ATAMAJOR;
+	ataraid_gendisk.major_name  = "ataraid";
+	ataraid_gendisk.minor_shift = 4;
+	ataraid_gendisk.max_p	    = 15;
+	ataraid_gendisk.sizes	    = &ataraid_gendisk_sizes[0];
+	ataraid_gendisk.nr_real	    = 16;
+	ataraid_gendisk.fops        = &ataraid_fops;
+	
+	
+	add_gendisk(&ataraid_gendisk);
+			
+	if (register_blkdev(ATAMAJOR, "ataraid", &ataraid_fops)) {
+		printk(KERN_ERR "ataraid: Could not get major %d \n",ATAMAJOR);
+		return -1;
+	}
+	
+	                
+	
+	blk_queue_make_request(BLK_DEFAULT_QUEUE(ATAMAJOR),ataraid_make_request);
+                                                                                     	
+	return 0;                                                        	
+}
+
+
+static void __exit ataraid_exit(void)
+{
+	unregister_blkdev(ATAMAJOR, "ataraid");
+	hardsect_size[ATAMAJOR] = NULL;
+	blk_size[ATAMAJOR] = NULL;
+	blksize_size[ATAMAJOR] = NULL;                       
+	max_readahead[ATAMAJOR] = NULL;
+
+	del_gendisk(&ataraid_gendisk);
+        
+	if (ataraid_gendisk.part) {
+		kfree(ataraid_gendisk.part);
+		ataraid_gendisk.part = NULL;
+	}
+}
+
+module_init(ataraid_init);
+module_exit(ataraid_exit);
+
+
+
+EXPORT_SYMBOL(ataraid_get_device);
+EXPORT_SYMBOL(ataraid_release_device);
+EXPORT_SYMBOL(ataraid_gendisk);
+EXPORT_SYMBOL(ataraid_register_disk);
+MODULE_LICENSE("GPL");
+