1 files changed, 137 insertions, 0 deletions
diff --git a/fs/zfs/dev.c b/fs/zfs/dev.c
new file mode 100644
index 000000000..d68372c80
--- /dev/null
+++ b/fs/zfs/dev.c
@@ -0,0 +1,137 @@
+/*
+ *
+ *	based on code of fs/reiserfs/dev.c by
+ *
+ *	(C) Copyright 2003 - 2004
+ *	Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com>
+ *
+ *	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 of the License, or
+ *	(at your option) any later version.
+ *
+ *	This program is distributed in the hope that it will be useful,
+ *	but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *	GNU General Public License for more details.
+ *
+ *	You should have received a copy of the GNU General Public License
+ *	along with this program; if not, write to the Free Software
+ *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <common.h>
+#include <config.h>
+#include <zfs_common.h>
+
+static block_dev_desc_t *zfs_block_dev_desc;
+static disk_partition_t part_info;
+
+int zfs_set_blk_dev(block_dev_desc_t *rbdd, int part)
+{
+	zfs_block_dev_desc = rbdd;
+
+	if (part == 0) {
+		/* disk doesn't use partition table */
+		part_info.start = 0;
+		part_info.size = rbdd->lba;
+		part_info.blksz = rbdd->blksz;
+	} else {
+		if (get_partition_info(zfs_block_dev_desc, part, &part_info))
+			return 0;
+	}
+
+	return part_info.size;
+}
+
+/* err */
+int zfs_devread(int sector, int byte_offset, int byte_len, char *buf)
+{
+	short sec_buffer[SECTOR_SIZE/sizeof(short)];
+	char *sec_buf = (char *)sec_buffer;
+	unsigned block_len;
+
+	/*
+	 *	Check partition boundaries
+	 */
+	if ((sector < 0) ||
+		((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS)) >=
+		 part_info.size)) {
+		/*		errnum = ERR_OUTSIDE_PART; */
+		printf(" ** zfs_devread() read outside partition sector %d\n", sector);
+		return 1;
+	}
+
+	/*
+	 *	Get the read to the beginning of a partition.
+	 */
+	sector += byte_offset >> SECTOR_BITS;
+	byte_offset &= SECTOR_SIZE - 1;
+
+	debug(" <%d, %d, %d>\n", sector, byte_offset, byte_len);
+
+	if (zfs_block_dev_desc == NULL) {
+		printf("** Invalid Block Device Descriptor (NULL)\n");
+		return 1;
+	}
+
+	if (byte_offset != 0) {
+		/* read first part which isn't aligned with start of sector */
+		if (zfs_block_dev_desc->block_read(zfs_block_dev_desc->dev,
+										   part_info.start + sector, 1,
+										   (unsigned long *) sec_buf) != 1) {
+			printf(" ** zfs_devread() read error **\n");
+			return 1;
+		}
+		memcpy(buf, sec_buf + byte_offset,
+			   min(SECTOR_SIZE - byte_offset, byte_len));
+		buf += min(SECTOR_SIZE - byte_offset, byte_len);
+		byte_len -= min(SECTOR_SIZE - byte_offset, byte_len);
+		sector++;
+	}
+
+	if (byte_len == 0)
+		return 0;
+
+	/*	read sector aligned part */
+	block_len = byte_len & ~(SECTOR_SIZE - 1);
+
+	if (block_len == 0) {
+		u8 p[SECTOR_SIZE];
+
+		block_len = SECTOR_SIZE;
+		zfs_block_dev_desc->block_read(zfs_block_dev_desc->dev,
+									   part_info.start + sector,
+									   1, (unsigned long *)p);
+		memcpy(buf, p, byte_len);
+		return 0;
+	}
+
+	if (zfs_block_dev_desc->block_read(zfs_block_dev_desc->dev,
+									   part_info.start + sector,
+									   block_len / SECTOR_SIZE,
+									   (unsigned long *) buf) !=
+		block_len / SECTOR_SIZE) {
+		printf(" ** zfs_devread() read error - block\n");
+		return 1;
+	}
+
+	block_len = byte_len & ~(SECTOR_SIZE - 1);
+	buf += block_len;
+	byte_len -= block_len;
+	sector += block_len / SECTOR_SIZE;
+
+	if (byte_len != 0) {
+		/* read rest of data which are not in whole sector */
+		if (zfs_block_dev_desc->
+			block_read(zfs_block_dev_desc->dev,
+					   part_info.start + sector, 1,
+					   (unsigned long *) sec_buf) != 1) {
+			printf(" ** zfs_devread() read error - last part\n");
+			return 1;
+		}
+		memcpy(buf, sec_buf, byte_len);
+	}
+	return 0;
+}