/* * dir.c * * PURPOSE * Directory handling routines for the OSTA-UDF(tm) filesystem. * * COPYRIGHT * This file is distributed under the terms of the GNU General Public * License (GPL). Copies of the GPL can be obtained from: * ftp://prep.ai.mit.edu/pub/gnu/GPL * Each contributing author retains all rights to their own work. * * (C) 1998-2004 Ben Fennema * * HISTORY * * 10/05/98 dgb Split directory operations into its own file * Implemented directory reads via do_udf_readdir * 10/06/98 Made directory operations work! * 11/17/98 Rewrote directory to support ICBTAG_FLAG_AD_LONG * 11/25/98 blf Rewrote directory handling (readdir+lookup) to support reading * across blocks. * 12/12/98 Split out the lookup code to namei.c. bulk of directory * code now in directory.c:udf_fileident_read. */ #include "udfdecl.h" #include <linux/string.h> #include <linux/errno.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/smp_lock.h> #include <linux/buffer_head.h> #include "udf_i.h" #include "udf_sb.h" /* Prototypes for file operations */ static int udf_readdir(struct file *, void *, filldir_t); static int do_udf_readdir(struct inode *, struct file *, filldir_t, void *); /* readdir and lookup functions */ const struct file_operations udf_dir_operations = { .read = generic_read_dir, .readdir = udf_readdir, .ioctl = udf_ioctl, .fsync = udf_fsync_file, }; /* * udf_readdir * * PURPOSE * Read a directory entry. * * DESCRIPTION * Optional - sys_getdents() will return -ENOTDIR if this routine is not * available. * * Refer to sys_getdents() in fs/readdir.c * sys_getdents() -> . * * PRE-CONDITIONS * filp Pointer to directory file. * buf Pointer to directory entry buffer. * filldir Pointer to filldir function. * * POST-CONDITIONS * <return> >=0 on success. * * HISTORY * July 1, 1997 - Andrew E. Mileski * Written, tested, and released. */ int udf_readdir(struct file *filp, void *dirent, filldir_t filldir) { struct inode *dir = filp->f_path.dentry->d_inode; int result; lock_kernel(); if (filp->f_pos == 0) { if (filldir(dirent, ".", 1, filp->f_pos, dir->i_ino, DT_DIR) < 0) { unlock_kernel(); return 0; } filp->f_pos++; } result = do_udf_readdir(dir, filp, filldir, dirent); unlock_kernel(); return result; } static int do_udf_readdir(struct inode *dir, struct file *filp, filldir_t filldir, void *dirent) { struct udf_fileident_bh fibh; struct fileIdentDesc *fi = NULL; struct fileIdentDesc cfi; int block, iblock; loff_t nf_pos = filp->f_pos - 1; int flen; char fname[UDF_NAME_LEN]; char *nameptr; uint16_t liu; uint8_t lfi; loff_t size = (udf_ext0_offset(dir) + dir->i_size) >> 2; struct buffer_head *tmp, *bha[16]; kernel_lb_addr eloc; uint32_t elen; sector_t offset; int i, num; unsigned int dt_type; struct extent_position epos = { NULL, 0, {0, 0} }; if (nf_pos >= size) return 0; if (nf_pos == 0) nf_pos = (udf_ext0_offset(dir) >> 2); fibh.soffset = fibh.eoffset = (nf_pos & ((dir->i_sb->s_blocksize - 1) >> 2)) << 2; if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_IN_ICB) { fibh.sbh = fibh.ebh = NULL; } else if (inode_bmap(dir, nf_pos >> (dir->i_sb->s_blocksize_bits - 2), &epos, &eloc, &elen, &offset) == (EXT_RECORDED_ALLOCATED >> 30)) { block = udf_get_lb_pblock(dir->i_sb, eloc, offset); if ((++offset << dir->i_sb->s_blocksize_bits) < elen) { if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_SHORT) epos.offset -= sizeof(short_ad); else if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_LONG) epos.offset -= sizeof(long_ad); } else { offset = 0; } if (!(fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block))) { brelse(epos.bh); return -EIO; } if (!(offset & ((16 >> (dir->i_sb->s_blocksize_bits - 9)) - 1))) { i = 16 >> (dir->i_sb->s_blocksize_bits - 9); if (i + offset > (elen >> dir->i_sb->s_blocksize_bits)) i = (elen >> dir->i_sb->s_blocksize_bits) - offset; for (num = 0; i > 0; i--) { block = udf_get_lb_pblock(dir->i_sb, eloc, offset + i); tmp = udf_tgetblk(dir->i_sb, block); if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp)) bha[num++] = tmp; else brelse(tmp); } if (num) { ll_rw_block(READA, num, bha); for (i = 0; i < num; i++) brelse(bha[i]); } } } else { brelse(epos.bh); return -ENOENT; } while (nf_pos < size) { filp->f_pos = nf_pos + 1; fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc, &elen, &offset); if (!fi) { if (fibh.sbh != fibh.ebh) brelse(fibh.ebh); brelse(fibh.sbh); brelse(epos.bh); return 0; } liu = le16_to_cpu(cfi.lengthOfImpUse); lfi = cfi.lengthFileIdent; if (fibh.sbh == fibh.ebh) { nameptr = fi->fileIdent + liu; } else { int poffset; /* Unpaded ending offset */ poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi; if (poffset >= lfi) { nameptr = (char *)(fibh.ebh->b_data + poffset - lfi); } else { nameptr = fname; memcpy(nameptr, fi->fileIdent + liu, lfi - poffset); memcpy(nameptr + lfi - poffset, fibh.ebh->b_data, poffset); } } if ((cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) { if (!UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNDELETE)) continue; } if ((cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) { if (!UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNHIDE)) continue; } if (cfi.fileCharacteristics & FID_FILE_CHAR_PARENT) { iblock = parent_ino(filp->f_path.dentry); flen = 2; memcpy(fname, "..", flen); dt_type = DT_DIR; } else { kernel_lb_addr tloc = lelb_to_cpu(cfi.icb.extLocation); iblock = udf_get_lb_pblock(dir->i_sb, tloc, 0); flen = udf_get_filename(dir->i_sb, nameptr, fname, lfi); dt_type = DT_UNKNOWN; } if (flen) { if (filldir(dirent, fname, flen, filp->f_pos, iblock, dt_type) < 0) { if (fibh.sbh != fibh.ebh) brelse(fibh.ebh); brelse(fibh.sbh); brelse(epos.bh); return 0; } } } /* end while */ filp->f_pos = nf_pos + 1; if (fibh.sbh != fibh.ebh) brelse(fibh.ebh); brelse(fibh.sbh); brelse(epos.bh); return 0; }