fs: Create a common fs_devread for ext4/reiserfs/zfs

The ext4, reiserfs and zfs filesystems all have their own implementation
of the same function, *_devread. Generalize this function into fs_devread
and put the code into fs/fs_internal.c.

Signed-off-by: Marek Behun <marek.behun@nic.cz>
[trini: Move fs/fs_internal.o hunk to the end of fs/Makefile as all
cases need it]
Signed-off-by: Tom Rini <trini@konsulko.com>

1 files changed, 4 insertions, 74 deletions

diff --git a/fs/reiserfs/dev.c b/fs/reiserfs/dev.c
index 5a1ab0a364..7b786e4ed3 100644
--- a/fs/reiserfs/dev.c
+++ b/fs/reiserfs/dev.c
@@ -9,7 +9,7 @@
 #include <common.h>
 #include <config.h>
 #include <reiserfs.h>
-
+#include <fs_internal.h>
 #include "reiserfs_private.h"
 
 static struct blk_desc *reiserfs_blk_desc;
@@ -22,78 +22,8 @@ void reiserfs_set_blk_dev(struct blk_desc *rbdd, disk_partition_t *info)
 	part_info = info;
 }
 
-
-int reiserfs_devread (int sector, int byte_offset, int byte_len, char *buf)
+int reiserfs_devread(int sector, int byte_offset, int byte_len, char *buf)
 {
-	char sec_buf[SECTOR_SIZE];
-	unsigned block_len;
-/*
-	unsigned len = byte_len;
-	u8 *start = buf;
-*/
-	/*
-	*  Check partition boundaries
-	*/
-	if (sector < 0
-	    || ((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS))
-	    >= part_info->size)) {
-/*		errnum = ERR_OUTSIDE_PART; */
-		printf (" ** reiserfs_devread() read outside partition\n");
-		return 0;
-	}
-
-	/*
-	 *  Get the read to the beginning of a partition.
-	 */
-	sector += byte_offset >> SECTOR_BITS;
-	byte_offset &= SECTOR_SIZE - 1;
-
-#if defined(DEBUG)
-	printf (" <%d, %d, %d> ", sector, byte_offset, byte_len);
-#endif
-
-
-	if (reiserfs_blk_desc == NULL)
-		return 0;
-
-
-	if (byte_offset != 0) {
-		/* read first part which isn't aligned with start of sector */
-		if (reiserfs_blk_desc->block_read(reiserfs_blk_desc,
-						  part_info->start + sector,
-						  1, (void *)sec_buf) != 1) {
-			printf (" ** reiserfs_devread() read error\n");
-			return 0;
-		}
-		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++;
-	}
-
-	/* read sector aligned part */
-	block_len = byte_len & ~(SECTOR_SIZE-1);
-	if (reiserfs_blk_desc->block_read(reiserfs_blk_desc,
-					  part_info->start + sector,
-					  block_len / SECTOR_SIZE, (void *)buf)
-			!= block_len/SECTOR_SIZE) {
-		printf (" ** reiserfs_devread() read error - block\n");
-		return 0;
-	}
-	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 (reiserfs_blk_desc->block_read(reiserfs_blk_desc,
-						  part_info->start + sector,
-						  1, (void *)sec_buf) != 1) {
-			printf (" ** reiserfs_devread() read error - last part\n");
-			return 0;
-		}
-		memcpy(buf, sec_buf, byte_len);
-	}
-
-	return 1;
+	return fs_devread(reiserfs_blk_desc, part_info, sector, byte_offset,
+			  byte_len, buf);
 }