- obsolete

[packages/kernel.git] / linux-2.4.2-blkioctl-sector.patch

--- linux/include/linux/fs.h.sector	Mon Feb 26 23:48:46 2001
+++ linux/include/linux/fs.h	Mon Feb 26 23:53:57 2001
@@ -187,6 +187,8 @@
 /* This was here just to show that the number is taken -
    probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
 #endif
+#define BLKGETLASTSECT  _IO(0x12,108) /* get last sector of block device */
+#define BLKSETLASTSECT  _IO(0x12,109) /* get last sector of block device */
 
 
 #define BMAP_IOCTL 1		/* obsolete - kept for compatibility */
--- linux/drivers/block/blkpg.c.sector	Fri Oct 27 02:35:47 2000
+++ linux/drivers/block/blkpg.c	Mon Feb 26 23:53:57 2001
@@ -39,6 +39,9 @@
 
 #include <asm/uaccess.h>
 
+static int set_last_sector( kdev_t dev, const void *param );
+static int get_last_sector( kdev_t dev, const void *param );
+
 /*
  * What is the data describing a partition?
  *
@@ -210,6 +213,16 @@
 	int intval;
 
 	switch (cmd) {
+		case BLKGETLASTSECT:
+			return get_last_sector(dev, (char *)(arg));
+
+		case BLKSETLASTSECT:
+			if( is_read_only(dev) )
+				return -EACCES;
+			if (!capable(CAP_SYS_ADMIN))
+				return -EACCES;
+			return set_last_sector(dev, (char *)(arg));
+
 		case BLKROSET:
 			if (!capable(CAP_SYS_ADMIN))
 				return -EACCES;
@@ -281,3 +294,209 @@
 }
 
 EXPORT_SYMBOL(blk_ioctl);
+
+ /*********************
+  * get_last_sector()
+  *  
+  * Description: This function will read any inaccessible blocks at the end
+  * 	of a device
+  * Why: Normal read/write calls through the block layer will not read the 
+  *      last sector of an odd-size disk. 
+  * parameters: 
+  *    dev: kdev_t -- which device to read
+  *    param: a pointer to a userspace struct. The struct has these members: 
+  *	block:  an int which denotes which block to return:
+  *		0 == Last block
+  * 		1 == Last block - 1
+  * 		n == Last block - n
+  *		This is validated so that only values of 
+  *		  <= ((total_sects + 1) % logical_block_size)  ||  0
+  *		  are allowed.
+  * 	block_contents: a pointer to userspace char*, this is where we write 
+  *	 returned blocks to.
+  * 	content_length: How big the userspace buffer is.
+  * return: 
+  *    0 on success
+  *   -ERRVAL on error.
+  *********************/
+int get_last_sector( kdev_t dev, const void *param )
+{   
+        struct buffer_head *bh;
+        struct gendisk *g;
+        int rc = 0;
+        unsigned int lastlba, readlba;
+        int orig_blksize = BLOCK_SIZE;
+        int hardblocksize;
+
+	struct {
+		unsigned int block;
+		size_t content_length;
+		char *block_contents;
+	} blk_ioctl_parameter;
+
+        if( !dev ) return -EINVAL;
+
+        if(copy_from_user(&blk_ioctl_parameter, param, sizeof(blk_ioctl_parameter)))
+		return -EFAULT;
+
+        g = get_gendisk( dev );
+
+        if( !g ) return -EINVAL;
+
+        lastlba = g->part[MINOR(dev)].nr_sects;
+
+        if( !lastlba ) return -EINVAL;
+
+        hardblocksize = get_hardsect_size(dev);
+        if( ! hardblocksize ) hardblocksize = 512;
+
+         /* Need to change the block size that the block layer uses */
+        if (blksize_size[MAJOR(dev)]){
+                orig_blksize = blksize_size[MAJOR(dev)][MINOR(dev)];
+        }
+
+         /* validate userspace input */
+        if( blk_ioctl_parameter.block == 0 )
+		goto good_params;
+
+	/* so we don't divide by zero below */  
+	if(orig_blksize == 0) 
+		return -EINVAL; 
+
+        if( blk_ioctl_parameter.block <= (lastlba % (orig_blksize / hardblocksize)))
+		goto good_params;
+
+	return -EINVAL; 
+
+good_params:
+        readlba = lastlba - blk_ioctl_parameter.block - 1;
+
+        if (orig_blksize != hardblocksize)
+                   set_blocksize(dev, hardblocksize);
+
+        bh =  bread(dev, readlba, hardblocksize);
+        if (!bh) {
+		/* We hit the end of the disk */
+		printk(KERN_WARNING
+			"get_last_sector ioctl: bread returned NULL.\n");
+		return -1;
+        }
+
+        rc = copy_to_user(blk_ioctl_parameter.block_contents, bh->b_data, 
+		(bh->b_size > blk_ioctl_parameter.content_length) ? 
+		blk_ioctl_parameter.content_length : bh->b_size);
+
+        brelse(bh);
+
+        /* change block size back */
+        if (orig_blksize != hardblocksize)
+                   set_blocksize(dev, orig_blksize);
+   
+        return rc;
+}
+
+ /*********************
+  * set_last_sector()
+  *  
+  * Description: This function will write to any inaccessible blocks at the end
+  * 	of a device
+  * Why: Normal read/write calls through the block layer will not read the 
+  *      last sector of an odd-size disk. 
+  * parameters: 
+  *    dev: kdev_t -- which device to read
+  *    sect: a pointer to a userspace struct. The struct has these members: 
+  *	block:  an int which denotes which block to return:
+  *		0 == Last block
+  * 		1 == Last block - 1
+  * 		n == Last block - n
+  *		This is validated so that only values of 
+  *		  <= ((total_sects + 1) % logical_block_size)  ||  0
+  *		  are allowed.
+  * 	block_contents: a pointer to userspace char*, this is where we write 
+  *	 returned blocks to.
+  * 	content_length: How big the userspace buffer is.
+  * return: 
+  *    0 on success
+  *   -ERRVAL on error.
+  *********************/
+int set_last_sector( kdev_t dev, const void *param ) 
+{
+        struct buffer_head *bh;
+        struct gendisk *g;
+        int rc = 0;
+        unsigned int lastlba, writelba;
+        int orig_blksize = BLOCK_SIZE;
+        int hardblocksize;
+
+	struct {
+		unsigned int block;
+		size_t content_length;
+		char *block_contents;
+	} blk_ioctl_parameter;
+
+        if( !dev ) return -EINVAL;
+
+	if(copy_from_user(&blk_ioctl_parameter, param, sizeof(blk_ioctl_parameter)))
+		return -EFAULT;
+
+        g = get_gendisk( dev );
+
+        if( !g ) return -EINVAL;
+    
+        lastlba = g->part[MINOR(dev)].nr_sects ;
+    
+        if( !lastlba ) return -EINVAL;
+    
+        hardblocksize = get_hardsect_size(dev);
+        if( ! hardblocksize ) hardblocksize = 512;
+    
+         /* Need to change the block size that the block layer uses */
+        if (blksize_size[MAJOR(dev)]){
+                orig_blksize = blksize_size[MAJOR(dev)][MINOR(dev)];
+        }
+
+         /* validate userspace input */
+        if( blk_ioctl_parameter.block == 0 )
+		goto good_params;
+
+	/* so we don't divide by zero below */  
+	if(orig_blksize == 0) 
+		return -EINVAL; 
+
+        if( blk_ioctl_parameter.block <= (lastlba % (orig_blksize / hardblocksize)))
+		goto good_params;
+
+	return -EINVAL; 
+
+good_params:
+        writelba = lastlba - blk_ioctl_parameter.block - 1;
+
+        if (orig_blksize != hardblocksize)
+                 set_blocksize(dev, hardblocksize);
+    
+        bh =  bread(dev, writelba, hardblocksize);
+        if (!bh) {
+		/* We hit the end of the disk */
+		printk(KERN_WARNING
+			"get_last_sector ioctl: getblk returned NULL.\n");
+		return -1;
+        }
+    
+        copy_from_user(bh->b_data, blk_ioctl_parameter.block_contents, 
+		(bh->b_size > blk_ioctl_parameter.content_length) ? 
+		blk_ioctl_parameter.content_length : bh->b_size);
+    
+        mark_buffer_dirty(bh);
+        ll_rw_block (WRITE, 1, &bh);
+        wait_on_buffer (bh);
+        if (!buffer_uptodate(bh))
+          rc=-1; 
+    
+        brelse(bh);
+    
+        /* change block size back */
+        if (orig_blksize != hardblocksize)
+                 set_blocksize(dev, orig_blksize);
+       
+       return rc;
+}
--- linux/drivers/scsi/sd.c.sector	Mon Feb 26 23:48:45 2001
+++ linux/drivers/scsi/sd.c	Mon Feb 26 23:53:57 2001
@@ -228,6 +228,8 @@
 		}
 		case BLKGETSIZE:
 		case BLKGETSIZE64:
+		case BLKGETLASTSECT:
+		case BLKSETLASTSECT:
 		case BLKROSET:
 		case BLKROGET:
 		case BLKRASET:
--- linux/drivers/ide/ide.c.sector	Mon Feb 26 23:48:49 2001
+++ linux/drivers/ide/ide.c	Mon Feb 26 23:53:57 2001
@@ -2664,6 +2664,8 @@
 			}
 			return 0;
 		}
+		case BLKGETLASTSECT:
+		case BLKSETLASTSECT:
 		case BLKROSET:
 		case BLKROGET:
 		case BLKFLSBUF: