fs: add filesystem switch libary, implement ls and fsload commands

Implement "ls" and "fsload" commands that act like {fat,ext2}{ls,load},
and transparently handle either file-system. This scheme could easily be
extended to other filesystem types; I only didn't do it for zfs because
I don't have any filesystems of that type to test with.

Replace the implementation of {fat,ext[24]}{ls,load} with this new code
too.

Signed-off-by: Stephen Warren <swarren@nvidia.com>

Makefile

@@ -260,7 +260,8 @@ LIBS-y += drivers/net/npe/libnpe.o
 endif
 LIBS-$(CONFIG_OF_EMBED) += dts/libdts.o
 LIBS-y += arch/$(ARCH)/lib/lib$(ARCH).o
-LIBS-y += fs/cbfs/libcbfs.o \
+LIBS-y += fs/libfs.o \
+	fs/cbfs/libcbfs.o \
 	fs/cramfs/libcramfs.o \
 	fs/ext4/libext4fs.o \
 	fs/fat/libfat.o \

common/Makefile

@@ -90,11 +90,6 @@ COBJS-$(CONFIG_CMD_ELF) += cmd_elf.o
 COBJS-$(CONFIG_SYS_HUSH_PARSER) += cmd_exit.o
 COBJS-$(CONFIG_CMD_EXT4) += cmd_ext4.o
 COBJS-$(CONFIG_CMD_EXT2) += cmd_ext2.o
-ifdef CONFIG_CMD_EXT4
-COBJS-y	+= cmd_ext_common.o
-else
-COBJS-$(CONFIG_CMD_EXT2) += cmd_ext_common.o
-endif
 COBJS-$(CONFIG_CMD_FAT) += cmd_fat.o
 COBJS-$(CONFIG_CMD_FDC)$(CONFIG_CMD_FDOS) += cmd_fdc.o
 COBJS-$(CONFIG_OF_LIBFDT) += cmd_fdt.o fdt_support.o
@@ -104,6 +99,7 @@ COBJS-$(CONFIG_CMD_FLASH) += cmd_flash.o
 ifdef CONFIG_FPGA
 COBJS-$(CONFIG_CMD_FPGA) += cmd_fpga.o
 endif
+COBJS-$(CONFIG_CMD_FS_GENERIC) += cmd_fs.o
 COBJS-$(CONFIG_CMD_GPIO) += cmd_gpio.o
 COBJS-$(CONFIG_CMD_I2C) += cmd_i2c.o
 COBJS-$(CONFIG_CMD_IDE) += cmd_ide.o

common/cmd_ext2.c

@@ -37,15 +37,11 @@
 /*
  * Ext2fs support
  */
-#include <common.h>
-#include <ext_common.h>
+#include <fs.h>
 
 int do_ext2ls (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
-	if (do_ext_ls(cmdtp, flag, argc, argv))
-		return -1;
-
-	return 0;
+	return do_ls(cmdtp, flag, argc, argv, FS_TYPE_EXT);
 }
 
 /******************************************************************************
@@ -53,10 +49,7 @@ int do_ext2ls (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  */
 int do_ext2load (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
-	if (do_ext_load(cmdtp, flag, argc, argv))
-		return -1;
-
-	return 0;
+	return do_fsload(cmdtp, flag, argc, argv, FS_TYPE_EXT);
 }
 
 U_BOOT_CMD(

common/cmd_ext4.c

@@ -47,10 +47,10 @@
 #include <image.h>
 #include <linux/ctype.h>
 #include <asm/byteorder.h>
-#include <ext_common.h>
 #include <ext4fs.h>
 #include <linux/stat.h>
 #include <malloc.h>
+#include <fs.h>
 
 #if defined(CONFIG_CMD_USB) && defined(CONFIG_USB_STORAGE)
 #include <usb.h>
@@ -59,18 +59,12 @@
 int do_ext4_load(cmd_tbl_t *cmdtp, int flag, int argc,
 						char *const argv[])
 {
-	if (do_ext_load(cmdtp, flag, argc, argv))
-		return -1;
-
-	return 0;
+	return do_fsload(cmdtp, flag, argc, argv, FS_TYPE_EXT);
 }
 
 int do_ext4_ls(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
 {
-	if (do_ext_ls(cmdtp, flag, argc, argv))
-		return -1;
-
-	return 0;
+	return do_ls(cmdtp, flag, argc, argv, FS_TYPE_EXT);
 }
 
 #if defined(CONFIG_CMD_EXT4_WRITE)

common/cmd_ext_common.c

@@ -1,197 +0,0 @@
-/*
- * (C) Copyright 2011 - 2012 Samsung Electronics
- * EXT2/4 filesystem implementation in Uboot by
- * Uma Shankar <uma.shankar@samsung.com>
- * Manjunatha C Achar <a.manjunatha@samsung.com>
- *
- * Ext4fs support
- * made from existing cmd_ext2.c file of Uboot
- *
- * (C) Copyright 2004
- * esd gmbh <www.esd-electronics.com>
- * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
- *
- * made from cmd_reiserfs by
- *
- * (C) Copyright 2003 - 2004
- * Sysgo Real-Time Solutions, 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., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
- *
- */
-
-/*
- * Changelog:
- *	0.1 - Newly created file for ext4fs support. Taken from cmd_ext2.c
- *	        file in uboot. Added ext4fs ls load and write support.
- */
-
-#include <common.h>
-#include <part.h>
-#include <config.h>
-#include <command.h>
-#include <image.h>
-#include <linux/ctype.h>
-#include <asm/byteorder.h>
-#include <ext_common.h>
-#include <ext4fs.h>
-#include <linux/stat.h>
-#include <malloc.h>
-
-#if defined(CONFIG_CMD_USB) && defined(CONFIG_USB_STORAGE)
-#include <usb.h>
-#endif
-
-#if !defined(CONFIG_DOS_PARTITION) && !defined(CONFIG_EFI_PARTITION)
-#error DOS or EFI partition support must be selected
-#endif
-
-#define DOS_PART_MAGIC_OFFSET		0x1fe
-#define DOS_FS_TYPE_OFFSET		0x36
-#define DOS_FS32_TYPE_OFFSET		0x52
-
-int do_ext_load(cmd_tbl_t *cmdtp, int flag, int argc,
-						char *const argv[])
-{
-	char *filename = NULL;
-	int dev, part;
-	ulong addr = 0;
-	int filelen;
-	disk_partition_t info;
-	block_dev_desc_t *dev_desc;
-	char buf[12];
-	unsigned long count;
-	const char *addr_str;
-
-	count = 0;
-	addr = simple_strtoul(argv[3], NULL, 16);
-	filename = getenv("bootfile");
-	switch (argc) {
-	case 3:
-		addr_str = getenv("loadaddr");
-		if (addr_str != NULL)
-			addr = simple_strtoul(addr_str, NULL, 16);
-		else
-			addr = CONFIG_SYS_LOAD_ADDR;
-
-		break;
-	case 4:
-		break;
-	case 5:
-		filename = argv[4];
-		break;
-	case 6:
-		filename = argv[4];
-		count = simple_strtoul(argv[5], NULL, 16);
-		break;
-
-	default:
-		return cmd_usage(cmdtp);
-	}
-
-	if (!filename) {
-		puts("** No boot file defined **\n");
-		return 1;
-	}
-
-	part = get_device_and_partition(argv[1], argv[2], &dev_desc, &info, 1);
-	if (part < 0)
-		return 1;
-
-	dev = dev_desc->dev;
-	printf("Loading file \"%s\" from %s device %d%c%c\n",
-		filename, argv[1], dev,
-		part ? ':' : ' ', part ? part + '0' : ' ');
-
-	ext4fs_set_blk_dev(dev_desc, &info);
-
-	if (!ext4fs_mount(info.size)) {
-		printf("** Bad ext2 partition or disk - %s %d:%d **\n",
-		       argv[1], dev, part);
-		ext4fs_close();
-		goto fail;
-	}
-
-	filelen = ext4fs_open(filename);
-	if (filelen < 0) {
-		printf("** File not found %s\n", filename);
-		ext4fs_close();
-		goto fail;
-	}
-	if ((count < filelen) && (count != 0))
-		filelen = count;
-
-	if (ext4fs_read((char *)addr, filelen) != filelen) {
-		printf("** Unable to read \"%s\" from %s %d:%d **\n",
-		       filename, argv[1], dev, part);
-		ext4fs_close();
-		goto fail;
-	}
-
-	ext4fs_close();
-	/* Loading ok, update default load address */
-	load_addr = addr;
-
-	printf("%d bytes read\n", filelen);
-	sprintf(buf, "%X", filelen);
-	setenv("filesize", buf);
-
-	return 0;
-fail:
-	return 1;
-}
-
-int do_ext_ls(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
-{
-	const char *filename = "/";
-	int dev;
-	int part;
-	block_dev_desc_t *dev_desc;
-	disk_partition_t info;
-
-	if (argc < 2)
-		return cmd_usage(cmdtp);
-
-	part = get_device_and_partition(argv[1], argv[2], &dev_desc, &info, 1);
-	if (part < 0)
-		return 1;
-
-	if (argc == 4)
-		filename = argv[3];
-
-	dev = dev_desc->dev;
-	ext4fs_set_blk_dev(dev_desc, &info);
-
-	if (!ext4fs_mount(info.size)) {
-		printf("** Bad ext2 partition or disk - %s %d:%d **\n",
-		       argv[1], dev, part);
-		ext4fs_close();
-		goto fail;
-	}
-
-	if (ext4fs_ls(filename)) {
-		printf("** Error extfs_ls() **\n");
-		ext4fs_close();
-		goto fail;
-	};
-
-	ext4fs_close();
-	return 0;
-
-fail:
-	return 1;
-}

common/cmd_fat.c

@@ -31,54 +31,11 @@
 #include <ata.h>
 #include <part.h>
 #include <fat.h>
-
+#include <fs.h>
 
 int do_fat_fsload (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
-	long size;
-	unsigned long offset;
-	unsigned long count = 0;
-	unsigned long pos = 0;
-	char buf [12];
-	block_dev_desc_t *dev_desc=NULL;
-	disk_partition_t info;
-	int part, dev;
-
-	if (argc < 5) {
-		printf("usage: fatload <interface> [<dev[:part]>] "
-			"<addr> <filename> [bytes [pos]]\n");
-		return 1;
-	}
-
-	part = get_device_and_partition(argv[1], argv[2], &dev_desc, &info, 1);
-	if (part < 0)
-		return 1;
-
-	dev = dev_desc->dev;
-	if (fat_set_blk_dev(dev_desc, &info) != 0) {
-		printf("\n** Unable to use %s %d:%d for fatload **\n",
-			argv[1], dev, part);
-		return 1;
-	}
-	offset = simple_strtoul(argv[3], NULL, 16);
-	if (argc >= 6)
-		count = simple_strtoul(argv[5], NULL, 16);
-	if (argc >= 7)
-		pos = simple_strtoul(argv[6], NULL, 16);
-	size = file_fat_read_at(argv[4], pos, (unsigned char *)offset, count);
-
-	if(size==-1) {
-		printf("\n** Unable to read \"%s\" from %s %d:%d **\n",
-			argv[4], argv[1], dev, part);
-		return 1;
-	}
-
-	printf("\n%ld bytes read\n", size);
-
-	sprintf(buf, "%lX", size);
-	setenv("filesize", buf);
-
-	return 0;
+	return do_fsload(cmdtp, flag, argc, argv, FS_TYPE_FAT);
 }
 
 
@@ -96,34 +53,7 @@ U_BOOT_CMD(
 
 int do_fat_ls (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
-	char *filename = "/";
-	int ret, dev, part;
-	block_dev_desc_t *dev_desc=NULL;
-	disk_partition_t info;
-
-	if (argc < 2) {
-		printf("usage: fatls <interface> [<dev[:part]>] [directory]\n");
-		return 0;
-	}
-
-	part = get_device_and_partition(argv[1], argv[2], &dev_desc, &info, 1);
-	if (part < 0)
-		return 1;
-
-	dev = dev_desc->dev;
-	if (fat_set_blk_dev(dev_desc, &info) != 0) {
-		printf("\n** Unable to use %s %d:%d for fatls **\n",
-			argv[1], dev, part);
-		return 1;
-	}
-	if (argc == 4)
-		ret = file_fat_ls(argv[3]);
-	else
-		ret = file_fat_ls(filename);
-
-	if(ret!=0)
-		printf("No Fat FS detected\n");
-	return ret;
+	return do_ls(cmdtp, flag, argc, argv, FS_TYPE_FAT);
 }
 
 U_BOOT_CMD(

common/cmd_fs.c

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Inspired by cmd_ext_common.c, cmd_fat.c.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <common.h>
+#include <command.h>
+#include <fs.h>
+
+int do_fsload_wrapper(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	return do_fsload(cmdtp, flag, argc, argv, FS_TYPE_ANY);
+}
+
+U_BOOT_CMD(
+	fsload,	7,	0,	do_fsload_wrapper,
+	"load binary file from a filesystem",
+	"<interface> [<dev[:part]> [<addr> [<filename> [bytes [pos]]]]]\n"
+	"    - Load binary file 'filename' from partition 'part' on device\n"
+	"       type 'interface' instance 'dev' to address 'addr' in memory.\n"
+	"      'bytes' gives the size to load in bytes.\n"
+	"      If 'bytes' is 0 or omitted, the file is read until the end.\n"
+	"      'pos' gives the file byte position to start reading from.\n"
+	"      If 'pos' is 0 or omitted, the file is read from the start."
+);
+
+int do_ls_wrapper(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	return do_ls(cmdtp, flag, argc, argv, FS_TYPE_ANY);
+}
+
+U_BOOT_CMD(
+	ls,	4,	1,	do_ls_wrapper,
+	"list files in a directory (default /)",
+	"<interface> [<dev[:part]> [directory]]\n"
+	"    - List files in directory 'directory' of partition 'part' on\n"
+	"      device type 'interface' instance 'dev'."
+);

fs/Makefile

@@ -0,0 +1,47 @@
+#
+# (C) Copyright 2000-2006
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+# Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# 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., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+include $(TOPDIR)/config.mk
+
+LIB	= $(obj)libfs.o
+
+COBJS-y				+= fs.o
+
+COBJS	:= $(COBJS-y)
+SRCS	:= $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+
+all:	$(LIB)
+
+$(LIB):	$(obj).depend $(OBJS)
+	$(call cmd_link_o_target, $(OBJS))
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################

fs/fs.c

@@ -0,0 +1,308 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <common.h>
+#include <part.h>
+#include <ext4fs.h>
+#include <fat.h>
+#include <fs.h>
+
+static block_dev_desc_t *fs_dev_desc;
+static disk_partition_t fs_partition;
+static int fs_type = FS_TYPE_ANY;
+
+static inline int fs_ls_unsupported(const char *dirname)
+{
+	printf("** Unrecognized filesystem type **\n");
+	return -1;
+}
+
+static inline int fs_read_unsupported(const char *filename, ulong addr,
+				      int offset, int len)
+{
+	printf("** Unrecognized filesystem type **\n");
+	return -1;
+}
+
+#ifdef CONFIG_FS_FAT
+static int fs_probe_fat(void)
+{
+	return fat_set_blk_dev(fs_dev_desc, &fs_partition);
+}
+
+static void fs_close_fat(void)
+{
+}
+
+#define fs_ls_fat file_fat_ls
+
+static int fs_read_fat(const char *filename, ulong addr, int offset, int len)
+{
+	int len_read;
+
+	len_read = file_fat_read_at(filename, offset,
+				    (unsigned char *)addr, len);
+	if (len_read == -1) {
+		printf("** Unable to read file %s **\n", filename);
+		return -1;
+	}
+
+	return len_read;
+}
+#else
+static inline int fs_probe_fat(void)
+{
+	return -1;
+}
+
+static inline void fs_close_fat(void)
+{
+}
+
+#define fs_ls_fat fs_ls_unsupported
+#define fs_read_fat fs_read_unsupported
+#endif
+
+#ifdef CONFIG_FS_EXT4
+static int fs_probe_ext(void)
+{
+	ext4fs_set_blk_dev(fs_dev_desc, &fs_partition);
+
+	if (!ext4fs_mount(fs_partition.size)) {
+		ext4fs_close();
+		return -1;
+	}
+
+	return 0;
+}
+
+static void fs_close_ext(void)
+{
+	ext4fs_close();
+}
+
+#define fs_ls_ext ext4fs_ls
+
+static int fs_read_ext(const char *filename, ulong addr, int offset, int len)
+{
+	int file_len;
+	int len_read;
+
+	if (offset != 0) {
+		printf("** Cannot support non-zero offset **\n");
+		return -1;
+	}
+
+	file_len = ext4fs_open(filename);
+	if (file_len < 0) {
+		printf("** File not found %s **\n", filename);
+		ext4fs_close();
+		return -1;
+	}
+
+	if (len == 0)
+		len = file_len;
+
+	len_read = ext4fs_read((char *)addr, len);
+	ext4fs_close();
+
+	if (len_read != len) {
+		printf("** Unable to read file %s **\n", filename);
+		return -1;
+	}
+
+	return len_read;
+}
+#else
+static inline int fs_probe_ext(void)
+{
+	return -1;
+}
+
+static inline void fs_close_ext(void)
+{
+}
+
+#define fs_ls_ext fs_ls_unsupported
+#define fs_read_ext fs_read_unsupported
+#endif
+
+static const struct {
+	int fstype;
+	int (*probe)(void);
+} fstypes[] = {
+	{
+		.fstype = FS_TYPE_FAT,
+		.probe = fs_probe_fat,
+	},
+	{
+		.fstype = FS_TYPE_EXT,
+		.probe = fs_probe_ext,
+	},
+};
+
+int fs_set_blk_dev(const char *ifname, const char *dev_part_str, int fstype)
+{
+	int part, i;
+
+	part = get_device_and_partition(ifname, dev_part_str, &fs_dev_desc,
+					&fs_partition, 1);
+	if (part < 0)
+		return -1;
+
+	for (i = 0; i < ARRAY_SIZE(fstypes); i++) {
+		if ((fstype != FS_TYPE_ANY) && (fstype != fstypes[i].fstype))
+			continue;
+
+		if (!fstypes[i].probe()) {
+			fs_type = fstypes[i].fstype;
+			return 0;
+		}
+	}
+
+	printf("** Unrecognized filesystem type **\n");
+	return -1;
+}
+
+static void fs_close(void)
+{
+	switch (fs_type) {
+	case FS_TYPE_FAT:
+		fs_close_fat();
+		break;
+	case FS_TYPE_EXT:
+		fs_close_ext();
+		break;
+	default:
+		break;
+	}
+
+	fs_type = FS_TYPE_ANY;
+}
+
+int fs_ls(const char *dirname)
+{
+	int ret;
+
+	switch (fs_type) {
+	case FS_TYPE_FAT:
+		ret = fs_ls_fat(dirname);
+		break;
+	case FS_TYPE_EXT:
+		ret = fs_ls_ext(dirname);
+		break;
+	default:
+		ret = fs_ls_unsupported(dirname);
+		break;
+	}
+
+	fs_close();
+
+	return ret;
+}
+
+int fs_read(const char *filename, ulong addr, int offset, int len)
+{
+	int ret;
+
+	switch (fs_type) {
+	case FS_TYPE_FAT:
+		ret = fs_read_fat(filename, addr, offset, len);
+		break;
+	case FS_TYPE_EXT:
+		ret = fs_read_ext(filename, addr, offset, len);
+		break;
+	default:
+		ret = fs_read_unsupported(filename, addr, offset, len);
+		break;
+	}
+
+	fs_close();
+
+	return ret;
+}
+
+int do_fsload(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
+		int fstype)
+{
+	unsigned long addr;
+	const char *addr_str;
+	const char *filename;
+	unsigned long bytes;
+	unsigned long pos;
+	int len_read;
+	char buf[12];
+
+	if (argc < 5)
+		return CMD_RET_USAGE;
+
+	if (fs_set_blk_dev(argv[1], argv[2], fstype))
+		return 1;
+
+	if (argc >= 4) {
+		addr = simple_strtoul(argv[3], NULL, 0);
+	} else {
+		addr_str = getenv("loadaddr");
+		if (addr_str != NULL)
+			addr = simple_strtoul(addr_str, NULL, 16);
+		else
+			addr = CONFIG_SYS_LOAD_ADDR;
+	}
+	if (argc >= 5) {
+		filename = argv[4];
+	} else {
+		filename = getenv("bootfile");
+		if (!filename) {
+			puts("** No boot file defined **\n");
+			return 1;
+		}
+	}
+	if (argc >= 6)
+		bytes = simple_strtoul(argv[5], NULL, 0);
+	else
+		bytes = 0;
+	if (argc >= 7)
+		pos = simple_strtoul(argv[6], NULL, 0);
+	else
+		pos = 0;
+
+	len_read = fs_read(filename, addr, pos, bytes);
+	if (len_read <= 0)
+		return 1;
+
+	printf("%d bytes read\n", len_read);
+
+	sprintf(buf, "0x%x", len_read);
+	setenv("filesize", buf);
+
+	return 0;
+}
+
+int do_ls(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
+	int fstype)
+{
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	if (fs_set_blk_dev(argv[1], (argc >= 3) ? argv[2] : NULL, fstype))
+		return 1;
+
+	if (fs_ls(argc == 4 ? argv[3] : "/"))
+		return 1;
+
+	return 0;
+}

include/ext_common.h

@@ -195,7 +195,4 @@ int do_ext4_load(cmd_tbl_t *cmdtp, int flag, int argc,
 int do_ext4_ls(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]);
 int do_ext4_write(cmd_tbl_t *cmdtp, int flag, int argc,
 				char *const argv[]);
-int do_ext_load(cmd_tbl_t *cmdtp, int flag, int argc,
-					char *const argv[]);
-int do_ext_ls(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]);
 #endif

include/fs.h

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef _FS_H
+#define _FS_H
+
+#include <common.h>
+
+#define FS_TYPE_ANY	0
+#define FS_TYPE_FAT	1
+#define FS_TYPE_EXT	2
+
+/*
+ * Tell the fs layer which block device an partition to use for future
+ * commands. This also internally identifies the filesystem that is present
+ * within the partition. The identification process may be limited to a
+ * specific filesystem type by passing FS_* in the fstype parameter.
+ *
+ * Returns 0 on success.
+ * Returns non-zero if there is an error accessing the disk or partition, or
+ * no known filesystem type could be recognized on it.
+ */
+int fs_set_blk_dev(const char *ifname, const char *dev_part_str, int fstype);
+
+/*
+ * Print the list of files on the partition previously set by fs_set_blk_dev(),
+ * in directory "dirname".
+ *
+ * Returns 0 on success. Returns non-zero on error.
+ */
+int fs_ls(const char *dirname);
+
+/*
+ * Read file "filename" from the partition previously set by fs_set_blk_dev(),
+ * to address "addr", starting at byte offset "offset", and reading "len"
+ * bytes. "offset" may be 0 to read from the start of the file. "len" may be
+ * 0 to read the entire file. Note that not all filesystem types support
+ * either/both offset!=0 or len!=0.
+ *
+ * Returns number of bytes read on success. Returns <= 0 on error.
+ */
+int fs_read(const char *filename, ulong addr, int offset, int len);
+
+/*
+ * Common implementation for various filesystem commands, optionally limited
+ * to a specific filesystem type via the fstype parameter.
+ */
+int do_fsload(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
+		int fstype);
+int do_ls(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
+		int fstype);
+
+#endif /* _FS_H */