1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * QNX4 file system, Linux implementation. 4 * 5 * Version : 0.2.1 6 * 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 18 static 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 struct qnx4_inode_entry *de; 24 struct qnx4_link_info *le; 25 unsigned long blknum; 26 int ix, ino; 27 int size; 28 29 QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size)); 30 QNX4DEBUG((KERN_INFO "pos = %ld\n", (long) ctx->pos)); 31 32 while (ctx->pos < inode->i_size) { 33 blknum = qnx4_block_map(inode, ctx->pos >> QNX4_BLOCK_SIZE_BITS); 34 bh = sb_bread(inode->i_sb, blknum); 35 if (bh == NULL) { 36 printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum); 37 return 0; 38 } 39 ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK; 40 for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) { 41 offset = ix * QNX4_DIR_ENTRY_SIZE; 42 de = (struct qnx4_inode_entry *) (bh->b_data + offset); 43 if (!de->di_fname[0]) 44 continue; 45 if (!(de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK))) 46 continue; 47 if (!(de->di_status & QNX4_FILE_LINK)) 48 size = QNX4_SHORT_NAME_MAX; 49 else 50 size = QNX4_NAME_MAX; 51 size = strnlen(de->di_fname, size); 52 QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, de->di_fname)); 53 if (!(de->di_status & QNX4_FILE_LINK)) 54 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1; 55 else { 56 le = (struct qnx4_link_info*)de; 57 ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) * 58 QNX4_INODES_PER_BLOCK + 59 le->dl_inode_ndx; 60 } 61 if (!dir_emit(ctx, de->di_fname, size, ino, DT_UNKNOWN)) { 62 brelse(bh); 63 return 0; 64 } 65 } 66 brelse(bh); 67 } 68 return 0; 69 } 70 71 const struct file_operations qnx4_dir_operations = 72 { 73 .llseek = generic_file_llseek, 74 .read = generic_read_dir, 75 .iterate_shared = qnx4_readdir, 76 .fsync = generic_file_fsync, 77 }; 78 79 const struct inode_operations qnx4_dir_inode_operations = 80 { 81 .lookup = qnx4_lookup, 82 }; 83