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-rw-r--r--fs/zfs/dev.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/fs/zfs/dev.c b/fs/zfs/dev.c
new file mode 100644
index 0000000000..d68372c808
--- /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;
+}