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      1 // SPDX-License-Identifier: GPL-2.0+
      2 /*
      3  * (C) Copyright 2011 - 2012 Samsung Electronics
      4  * EXT4 filesystem implementation in Uboot by
      5  * Uma Shankar <uma.shankar (at) samsung.com>
      6  * Manjunatha C Achar <a.manjunatha (at) samsung.com>
      7  *
      8  * ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
      9  *		       Ext4 read optimization taken from Open-Moko
     10  *		       Qi bootloader
     11  *
     12  * (C) Copyright 2004
     13  * esd gmbh <www.esd-electronics.com>
     14  * Reinhard Arlt <reinhard.arlt (at) esd-electronics.com>
     15  *
     16  * based on code from grub2 fs/ext2.c and fs/fshelp.c by
     17  * GRUB  --  GRand Unified Bootloader
     18  * Copyright (C) 2003, 2004  Free Software Foundation, Inc.
     19  *
     20  * ext4write : Based on generic ext4 protocol.
     21  */
     22 
     23 #include <common.h>
     24 #include <ext_common.h>
     25 #include <ext4fs.h>
     26 #include "ext4_common.h"
     27 #include <div64.h>
     28 
     29 int ext4fs_symlinknest;
     30 struct ext_filesystem ext_fs;
     31 
     32 struct ext_filesystem *get_fs(void)
     33 {
     34 	return &ext_fs;
     35 }
     36 
     37 void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot)
     38 {
     39 	if ((node != &ext4fs_root->diropen) && (node != currroot))
     40 		free(node);
     41 }
     42 
     43 /*
     44  * Taken from openmoko-kernel mailing list: By Andy green
     45  * Optimized read file API : collects and defers contiguous sector
     46  * reads into one potentially more efficient larger sequential read action
     47  */
     48 int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
     49 		loff_t len, char *buf, loff_t *actread)
     50 {
     51 	struct ext_filesystem *fs = get_fs();
     52 	int i;
     53 	lbaint_t blockcnt;
     54 	int log2blksz = fs->dev_desc->log2blksz;
     55 	int log2_fs_blocksize = LOG2_BLOCK_SIZE(node->data) - log2blksz;
     56 	int blocksize = (1 << (log2_fs_blocksize + log2blksz));
     57 	unsigned int filesize = le32_to_cpu(node->inode.size);
     58 	lbaint_t previous_block_number = -1;
     59 	lbaint_t delayed_start = 0;
     60 	lbaint_t delayed_extent = 0;
     61 	lbaint_t delayed_skipfirst = 0;
     62 	lbaint_t delayed_next = 0;
     63 	char *delayed_buf = NULL;
     64 	short status;
     65 
     66 	if (blocksize <= 0)
     67 		return -1;
     68 
     69 	/* Adjust len so it we can't read past the end of the file. */
     70 	if (len + pos > filesize)
     71 		len = (filesize - pos);
     72 
     73 	blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
     74 
     75 	for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
     76 		long int blknr;
     77 		int blockoff = pos - (blocksize * i);
     78 		int blockend = blocksize;
     79 		int skipfirst = 0;
     80 		blknr = read_allocated_block(&(node->inode), i);
     81 		if (blknr < 0)
     82 			return -1;
     83 
     84 		blknr = blknr << log2_fs_blocksize;
     85 
     86 		/* Last block.  */
     87 		if (i == blockcnt - 1) {
     88 			blockend = (len + pos) - (blocksize * i);
     89 
     90 			/* The last portion is exactly blocksize. */
     91 			if (!blockend)
     92 				blockend = blocksize;
     93 		}
     94 
     95 		/* First block. */
     96 		if (i == lldiv(pos, blocksize)) {
     97 			skipfirst = blockoff;
     98 			blockend -= skipfirst;
     99 		}
    100 		if (blknr) {
    101 			int status;
    102 
    103 			if (previous_block_number != -1) {
    104 				if (delayed_next == blknr) {
    105 					delayed_extent += blockend;
    106 					delayed_next += blockend >> log2blksz;
    107 				} else {	/* spill */
    108 					status = ext4fs_devread(delayed_start,
    109 							delayed_skipfirst,
    110 							delayed_extent,
    111 							delayed_buf);
    112 					if (status == 0)
    113 						return -1;
    114 					previous_block_number = blknr;
    115 					delayed_start = blknr;
    116 					delayed_extent = blockend;
    117 					delayed_skipfirst = skipfirst;
    118 					delayed_buf = buf;
    119 					delayed_next = blknr +
    120 						(blockend >> log2blksz);
    121 				}
    122 			} else {
    123 				previous_block_number = blknr;
    124 				delayed_start = blknr;
    125 				delayed_extent = blockend;
    126 				delayed_skipfirst = skipfirst;
    127 				delayed_buf = buf;
    128 				delayed_next = blknr +
    129 					(blockend >> log2blksz);
    130 			}
    131 		} else {
    132 			int n;
    133 			if (previous_block_number != -1) {
    134 				/* spill */
    135 				status = ext4fs_devread(delayed_start,
    136 							delayed_skipfirst,
    137 							delayed_extent,
    138 							delayed_buf);
    139 				if (status == 0)
    140 					return -1;
    141 				previous_block_number = -1;
    142 			}
    143 			/* Zero no more than `len' bytes. */
    144 			n = blocksize - skipfirst;
    145 			if (n > len)
    146 				n = len;
    147 			memset(buf, 0, n);
    148 		}
    149 		buf += blocksize - skipfirst;
    150 	}
    151 	if (previous_block_number != -1) {
    152 		/* spill */
    153 		status = ext4fs_devread(delayed_start,
    154 					delayed_skipfirst, delayed_extent,
    155 					delayed_buf);
    156 		if (status == 0)
    157 			return -1;
    158 		previous_block_number = -1;
    159 	}
    160 
    161 	*actread  = len;
    162 	return 0;
    163 }
    164 
    165 int ext4fs_ls(const char *dirname)
    166 {
    167 	struct ext2fs_node *dirnode = NULL;
    168 	int status;
    169 
    170 	if (dirname == NULL)
    171 		return 0;
    172 
    173 	status = ext4fs_find_file(dirname, &ext4fs_root->diropen, &dirnode,
    174 				  FILETYPE_DIRECTORY);
    175 	if (status != 1) {
    176 		printf("** Can not find directory. **\n");
    177 		if (dirnode)
    178 			ext4fs_free_node(dirnode, &ext4fs_root->diropen);
    179 		return 1;
    180 	}
    181 
    182 	ext4fs_iterate_dir(dirnode, NULL, NULL, NULL);
    183 	ext4fs_free_node(dirnode, &ext4fs_root->diropen);
    184 
    185 	return 0;
    186 }
    187 
    188 int ext4fs_exists(const char *filename)
    189 {
    190 	loff_t file_len;
    191 	int ret;
    192 
    193 	ret = ext4fs_open(filename, &file_len);
    194 	return ret == 0;
    195 }
    196 
    197 int ext4fs_size(const char *filename, loff_t *size)
    198 {
    199 	return ext4fs_open(filename, size);
    200 }
    201 
    202 int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread)
    203 {
    204 	if (ext4fs_root == NULL || ext4fs_file == NULL)
    205 		return -1;
    206 
    207 	return ext4fs_read_file(ext4fs_file, offset, len, buf, actread);
    208 }
    209 
    210 int ext4fs_probe(struct blk_desc *fs_dev_desc,
    211 		 disk_partition_t *fs_partition)
    212 {
    213 	ext4fs_set_blk_dev(fs_dev_desc, fs_partition);
    214 
    215 	if (!ext4fs_mount(fs_partition->size)) {
    216 		ext4fs_close();
    217 		return -1;
    218 	}
    219 
    220 	return 0;
    221 }
    222 
    223 int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
    224 		   loff_t *len_read)
    225 {
    226 	loff_t file_len;
    227 	int ret;
    228 
    229 	ret = ext4fs_open(filename, &file_len);
    230 	if (ret < 0) {
    231 		printf("** File not found %s **\n", filename);
    232 		return -1;
    233 	}
    234 
    235 	if (len == 0)
    236 		len = file_len;
    237 
    238 	return ext4fs_read(buf, offset, len, len_read);
    239 }
    240 
    241 int ext4fs_uuid(char *uuid_str)
    242 {
    243 	if (ext4fs_root == NULL)
    244 		return -1;
    245 
    246 #ifdef CONFIG_LIB_UUID
    247 	uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id,
    248 			uuid_str, UUID_STR_FORMAT_STD);
    249 
    250 	return 0;
    251 #else
    252 	return -ENOSYS;
    253 #endif
    254 }
    255