patch-2.3.17 linux/fs/udf/lowlevel.c

• Lines: 150
• Date: Sat Sep 4 12:42:30 1999
• Orig file: v2.3.16/linux/fs/udf/lowlevel.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.16/linux/fs/udf/lowlevel.c linux/fs/udf/lowlevel.c
@@ -0,0 +1,149 @@
+/*
+ * lowlevel.c
+ *
+ * PURPOSE
+ *  Low Level Device Routines for the UDF filesystem
+ *
+ * CONTACTS
+ *	E-mail regarding any portion of the Linux UDF file system should be
+ *	directed to the development team mailing list (run by majordomo):
+ *		linux_udf@hootie.lvld.hp.com
+ *
+ * COPYRIGHT
+ *	This file is distributed under the terms of the GNU General Public
+ *	License (GPL). Copies of the GPL can be obtained from:
+ *		ftp://prep.ai.mit.edu/pub/gnu/GPL
+ *	Each contributing author retains all rights to their own work.
+ *
+ *  (C) 1999 Ben Fennema
+ *
+ * HISTORY
+ *
+ *  03/26/99 blf  Created.
+ */
+
+#include "udfdecl.h"
+
+#include <linux/blkdev.h>
+#include <linux/cdrom.h>
+#include <asm/uaccess.h>
+#include <scsi/scsi.h>
+
+typedef struct scsi_device Scsi_Device;
+typedef struct scsi_cmnd   Scsi_Cmnd;
+
+#include <scsi/scsi_ioctl.h>
+
+#include <linux/udf_fs.h>
+#include "udf_sb.h"
+
+unsigned int 
+udf_get_last_session(kdev_t dev)
+{
+	struct cdrom_multisession ms_info;
+	unsigned int vol_desc_start;
+	struct inode inode_fake;
+	extern struct file_operations * get_blkfops(unsigned int);
+	int i;
+
+	vol_desc_start=0;
+	if (get_blkfops(MAJOR(dev))->ioctl!=NULL)
+	{
+		/* Whoops.  We must save the old FS, since otherwise
+		 * we would destroy the kernels idea about FS on root
+		 * mount in read_super... [chexum]
+		 */
+		mm_segment_t old_fs=get_fs();
+		inode_fake.i_rdev=dev;
+		ms_info.addr_format=CDROM_LBA;
+		set_fs(KERNEL_DS);
+		i=get_blkfops(MAJOR(dev))->ioctl(&inode_fake,
+						NULL,
+						CDROMMULTISESSION,
+						(unsigned long) &ms_info);
+		set_fs(old_fs);
+
+#define WE_OBEY_THE_WRITTEN_STANDARDS 1
+
+		if (i == 0)
+		{
+			udf_debug("XA disk: %s, vol_desc_start=%d\n",
+				(ms_info.xa_flag ? "yes" : "no"), ms_info.addr.lba);
+#if WE_OBEY_THE_WRITTEN_STANDARDS
+			if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
+#endif
+				vol_desc_start = ms_info.addr.lba;
+		}
+		else
+		{
+			udf_debug("CDROMMULTISESSION not supported: rc=%d\n", i);
+		}
+	}
+	else
+	{
+		udf_debug("Device doesn't know how to ioctl?\n");
+	}
+	return vol_desc_start;
+}
+
+unsigned int
+udf_get_last_block(kdev_t dev, int *flags)
+{
+	extern int *blksize_size[];
+	struct inode inode_fake;
+	extern struct file_operations * get_blkfops(unsigned int);
+	int ret;
+	unsigned long lblock;
+	unsigned int hbsize = get_hardblocksize(dev);
+	unsigned int mult = 0;
+	unsigned int div = 0;
+
+	if (!hbsize)
+		hbsize = 512;
+
+	if (hbsize > blksize_size[MAJOR(dev)][MINOR(dev)])
+		mult = hbsize / blksize_size[MAJOR(dev)][MINOR(dev)];
+	else if (blksize_size[MAJOR(dev)][MINOR(dev)] > hbsize)
+		div = blksize_size[MAJOR(dev)][MINOR(dev)] / hbsize;
+
+	if (get_blkfops(MAJOR(dev))->ioctl!=NULL)
+	{
+      /* Whoops.  We must save the old FS, since otherwise
+       * we would destroy the kernels idea about FS on root
+       * mount in read_super... [chexum]
+       */
+		mm_segment_t old_fs=get_fs();
+		inode_fake.i_rdev=dev;
+		set_fs(KERNEL_DS);
+
+		lblock = 0;
+		ret = get_blkfops(MAJOR(dev))->ioctl(&inode_fake,
+			NULL,
+			BLKGETSIZE,
+			(unsigned long) &lblock);
+
+		if (!ret) /* Hard Disk */
+		{
+			if (mult)
+				lblock *= mult;
+			else if (div)
+				lblock /= div;
+		}
+		else /* CDROM */
+		{
+			ret = get_blkfops(MAJOR(dev))->ioctl(&inode_fake,
+				NULL,
+				CDROM_LAST_WRITTEN,
+				(unsigned long) &lblock);
+		}
+
+		set_fs(old_fs);
+		if (!ret)
+			return lblock - 1;
+	}
+	else
+	{
+		udf_debug("Device doesn't know how to ioctl?\n");
+	}
+	return 0;
+}