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1// SPDX-License-Identifier: GPL-2.02/*3 * QNX4 file system, Linux implementation.4 *5 * Version : 0.2.16 *7 * Using parts of the xiafs filesystem.8 *9 * History :10 *11 * 28-05-1998 by Richard Frowijn : first release.12 * 20-06-1998 by Frank Denis : Linux 2.1.99+ & dcache support.13 */14 15#include <linux/buffer_head.h>16#include "qnx4.h"17 18static int qnx4_readdir(struct file *file, struct dir_context *ctx)19{20 struct inode *inode = file_inode(file);21 unsigned int offset;22 struct buffer_head *bh;23 unsigned long blknum;24 int ix, ino;25 int size;26 27 QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size));28 QNX4DEBUG((KERN_INFO "pos = %ld\n", (long) ctx->pos));29 30 while (ctx->pos < inode->i_size) {31 blknum = qnx4_block_map(inode, ctx->pos >> QNX4_BLOCK_SIZE_BITS);32 bh = sb_bread(inode->i_sb, blknum);33 if (bh == NULL) {34 printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);35 return 0;36 }37 ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;38 for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) {39 union qnx4_directory_entry *de;40 const char *fname;41 42 offset = ix * QNX4_DIR_ENTRY_SIZE;43 de = (union qnx4_directory_entry *) (bh->b_data + offset);44 45 fname = get_entry_fname(de, &size);46 if (!fname)47 continue;48 49 if (!(de->de_status & QNX4_FILE_LINK)) {50 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;51 } else {52 ino = ( le32_to_cpu(de->link.dl_inode_blk) - 1 ) *53 QNX4_INODES_PER_BLOCK +54 de->link.dl_inode_ndx;55 }56 57 QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, fname));58 if (!dir_emit(ctx, fname, size, ino, DT_UNKNOWN)) {59 brelse(bh);60 return 0;61 }62 }63 brelse(bh);64 }65 return 0;66}67 68const struct file_operations qnx4_dir_operations =69{70 .llseek = generic_file_llseek,71 .read = generic_read_dir,72 .iterate_shared = qnx4_readdir,73 .fsync = generic_file_fsync,74};75 76const struct inode_operations qnx4_dir_inode_operations =77{78 .lookup = qnx4_lookup,79};80