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 <linux/filelock.h> 17 #include "qnx4.h" 18 19 static int qnx4_readdir(struct file *file, struct dir_context *ctx) 20 { 21 struct inode *inode = file_inode(file); 22 unsigned int offset; 23 struct buffer_head *bh; 24 unsigned long blknum; 25 int ix, ino; 26 int size; 27 28 QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size)); 29 QNX4DEBUG((KERN_INFO "pos = %ld\n", (long) ctx->pos)); 30 31 while (ctx->pos < inode->i_size) { 32 blknum = qnx4_block_map(inode, ctx->pos >> QNX4_BLOCK_SIZE_BITS); 33 bh = sb_bread(inode->i_sb, blknum); 34 if (bh == NULL) { 35 printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum); 36 return 0; 37 } 38 ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK; 39 for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) { 40 union qnx4_directory_entry *de; 41 const char *fname; 42 43 offset = ix * QNX4_DIR_ENTRY_SIZE; 44 de = (union qnx4_directory_entry *) (bh->b_data + offset); 45 46 fname = get_entry_fname(de, &size); 47 if (!fname) 48 continue; 49 50 if (!(de->de_status & QNX4_FILE_LINK)) { 51 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1; 52 } else { 53 ino = ( le32_to_cpu(de->link.dl_inode_blk) - 1 ) * 54 QNX4_INODES_PER_BLOCK + 55 de->link.dl_inode_ndx; 56 } 57 58 QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, fname)); 59 if (!dir_emit(ctx, fname, size, ino, DT_UNKNOWN)) { 60 brelse(bh); 61 return 0; 62 } 63 } 64 brelse(bh); 65 } 66 return 0; 67 } 68 69 const struct file_operations qnx4_dir_operations = 70 { 71 .llseek = generic_file_llseek, 72 .read = generic_read_dir, 73 .iterate_shared = qnx4_readdir, 74 .fsync = generic_file_fsync, 75 .setlease = generic_setlease, 76 }; 77 78 const struct inode_operations qnx4_dir_inode_operations = 79 { 80 .lookup = qnx4_lookup, 81 }; 82