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1// SPDX-License-Identifier: GPL-2.02/*3 *  linux/fs/ufs/ialloc.c4 *5 * Copyright (c) 19986 * Daniel Pirkl <daniel.pirkl@email.cz>7 * Charles University, Faculty of Mathematics and Physics8 *9 *  from10 *11 *  linux/fs/ext2/ialloc.c12 *13 * Copyright (C) 1992, 1993, 1994, 199514 * Remy Card (card@masi.ibp.fr)15 * Laboratoire MASI - Institut Blaise Pascal16 * Universite Pierre et Marie Curie (Paris VI)17 *18 *  BSD ufs-inspired inode and directory allocation by 19 *  Stephen Tweedie (sct@dcs.ed.ac.uk), 199320 *  Big-endian to little-endian byte-swapping/bitmaps by21 *        David S. Miller (davem@caip.rutgers.edu), 199522 *23 * UFS2 write support added by24 * Evgeniy Dushistov <dushistov@mail.ru>, 200725 */26 27#include <linux/fs.h>28#include <linux/time.h>29#include <linux/stat.h>30#include <linux/string.h>31#include <linux/buffer_head.h>32#include <linux/sched.h>33#include <linux/bitops.h>34#include <asm/byteorder.h>35 36#include "ufs_fs.h"37#include "ufs.h"38#include "swab.h"39#include "util.h"40 41/*42 * NOTE! When we get the inode, we're the only people43 * that have access to it, and as such there are no44 * race conditions we have to worry about. The inode45 * is not on the hash-lists, and it cannot be reached46 * through the filesystem because the directory entry47 * has been deleted earlier.48 *49 * HOWEVER: we must make sure that we get no aliases,50 * which means that we have to call "clear_inode()"51 * _before_ we mark the inode not in use in the inode52 * bitmaps. Otherwise a newly created file might use53 * the same inode number (not actually the same pointer54 * though), and then we'd have two inodes sharing the55 * same inode number and space on the harddisk.56 */57void ufs_free_inode (struct inode * inode)58{59	struct super_block * sb;60	struct ufs_sb_private_info * uspi;61	struct ufs_cg_private_info * ucpi;62	struct ufs_cylinder_group * ucg;63	int is_directory;64	unsigned ino, cg, bit;65	66	UFSD("ENTER, ino %lu\n", inode->i_ino);67 68	sb = inode->i_sb;69	uspi = UFS_SB(sb)->s_uspi;70	71	ino = inode->i_ino;72 73	mutex_lock(&UFS_SB(sb)->s_lock);74 75	if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {76		ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);77		mutex_unlock(&UFS_SB(sb)->s_lock);78		return;79	}80	81	cg = ufs_inotocg (ino);82	bit = ufs_inotocgoff (ino);83	ucpi = ufs_load_cylinder (sb, cg);84	if (!ucpi) {85		mutex_unlock(&UFS_SB(sb)->s_lock);86		return;87	}88	ucg = ubh_get_ucg(UCPI_UBH(ucpi));89	if (!ufs_cg_chkmagic(sb, ucg))90		ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number");91 92	ucg->cg_time = ufs_get_seconds(sb);93 94	is_directory = S_ISDIR(inode->i_mode);95 96	if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit))97		ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino);98	else {99		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit);100		if (ino < ucpi->c_irotor)101			ucpi->c_irotor = ino;102		fs32_add(sb, &ucg->cg_cs.cs_nifree, 1);103		uspi->cs_total.cs_nifree++;104		fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1);105 106		if (is_directory) {107			fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1);108			uspi->cs_total.cs_ndir--;109			fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1);110		}111	}112 113	ubh_mark_buffer_dirty (USPI_UBH(uspi));114	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));115	if (sb->s_flags & SB_SYNCHRONOUS)116		ubh_sync_block(UCPI_UBH(ucpi));117	118	ufs_mark_sb_dirty(sb);119	mutex_unlock(&UFS_SB(sb)->s_lock);120	UFSD("EXIT\n");121}122 123/*124 * Nullify new chunk of inodes,125 * BSD people also set ui_gen field of inode126 * during nullification, but we not care about127 * that because of linux ufs do not support NFS128 */129static void ufs2_init_inodes_chunk(struct super_block *sb,130				   struct ufs_cg_private_info *ucpi,131				   struct ufs_cylinder_group *ucg)132{133	struct buffer_head *bh;134	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;135	sector_t beg = uspi->s_sbbase +136		ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg +137			      fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk));138	sector_t end = beg + uspi->s_fpb;139 140	UFSD("ENTER cgno %d\n", ucpi->c_cgx);141 142	for (; beg < end; ++beg) {143		bh = sb_getblk(sb, beg);144		lock_buffer(bh);145		memset(bh->b_data, 0, sb->s_blocksize);146		set_buffer_uptodate(bh);147		mark_buffer_dirty(bh);148		unlock_buffer(bh);149		if (sb->s_flags & SB_SYNCHRONOUS)150			sync_dirty_buffer(bh);151		brelse(bh);152	}153 154	fs32_add(sb, &ucg->cg_u.cg_u2.cg_initediblk, uspi->s_inopb);155	ubh_mark_buffer_dirty(UCPI_UBH(ucpi));156	if (sb->s_flags & SB_SYNCHRONOUS)157		ubh_sync_block(UCPI_UBH(ucpi));158 159	UFSD("EXIT\n");160}161 162/*163 * There are two policies for allocating an inode.  If the new inode is164 * a directory, then a forward search is made for a block group with both165 * free space and a low directory-to-inode ratio; if that fails, then of166 * the groups with above-average free space, that group with the fewest167 * directories already is chosen.168 *169 * For other inodes, search forward from the parent directory's block170 * group to find a free inode.171 */172struct inode *ufs_new_inode(struct inode *dir, umode_t mode)173{174	struct super_block * sb;175	struct ufs_sb_info * sbi;176	struct ufs_sb_private_info * uspi;177	struct ufs_cg_private_info * ucpi;178	struct ufs_cylinder_group * ucg;179	struct inode * inode;180	struct timespec64 ts;181	unsigned cg, bit, i, j, start;182	struct ufs_inode_info *ufsi;183	int err = -ENOSPC;184 185	UFSD("ENTER\n");186	187	/* Cannot create files in a deleted directory */188	if (!dir || !dir->i_nlink)189		return ERR_PTR(-EPERM);190	sb = dir->i_sb;191	inode = new_inode(sb);192	if (!inode)193		return ERR_PTR(-ENOMEM);194	ufsi = UFS_I(inode);195	sbi = UFS_SB(sb);196	uspi = sbi->s_uspi;197 198	mutex_lock(&sbi->s_lock);199 200	/*201	 * Try to place the inode in its parent directory202	 */203	i = ufs_inotocg(dir->i_ino);204	if (sbi->fs_cs(i).cs_nifree) {205		cg = i;206		goto cg_found;207	}208 209	/*210	 * Use a quadratic hash to find a group with a free inode211	 */212	for ( j = 1; j < uspi->s_ncg; j <<= 1 ) {213		i += j;214		if (i >= uspi->s_ncg)215			i -= uspi->s_ncg;216		if (sbi->fs_cs(i).cs_nifree) {217			cg = i;218			goto cg_found;219		}220	}221 222	/*223	 * That failed: try linear search for a free inode224	 */225	i = ufs_inotocg(dir->i_ino) + 1;226	for (j = 2; j < uspi->s_ncg; j++) {227		i++;228		if (i >= uspi->s_ncg)229			i = 0;230		if (sbi->fs_cs(i).cs_nifree) {231			cg = i;232			goto cg_found;233		}234	}235 236	goto failed;237 238cg_found:239	ucpi = ufs_load_cylinder (sb, cg);240	if (!ucpi) {241		err = -EIO;242		goto failed;243	}244	ucg = ubh_get_ucg(UCPI_UBH(ucpi));245	if (!ufs_cg_chkmagic(sb, ucg)) 246		ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number");247 248	start = ucpi->c_irotor;249	bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start);250	if (!(bit < uspi->s_ipg)) {251		bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start);252		if (!(bit < start)) {253			ufs_error (sb, "ufs_new_inode",254			    "cylinder group %u corrupted - error in inode bitmap\n", cg);255			err = -EIO;256			goto failed;257		}258	}259	UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg);260	if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit))261		ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit);262	else {263		ufs_panic (sb, "ufs_new_inode", "internal error");264		err = -EIO;265		goto failed;266	}267 268	if (uspi->fs_magic == UFS2_MAGIC) {269		u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk);270 271		if (bit + uspi->s_inopb > initediblk &&272		    initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk))273			ufs2_init_inodes_chunk(sb, ucpi, ucg);274	}275 276	fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1);277	uspi->cs_total.cs_nifree--;278	fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1);279	280	if (S_ISDIR(mode)) {281		fs32_add(sb, &ucg->cg_cs.cs_ndir, 1);282		uspi->cs_total.cs_ndir++;283		fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1);284	}285	ubh_mark_buffer_dirty (USPI_UBH(uspi));286	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));287	if (sb->s_flags & SB_SYNCHRONOUS)288		ubh_sync_block(UCPI_UBH(ucpi));289	ufs_mark_sb_dirty(sb);290 291	inode->i_ino = cg * uspi->s_ipg + bit;292	inode_init_owner(&nop_mnt_idmap, inode, dir, mode);293	inode->i_blocks = 0;294	inode->i_generation = 0;295	simple_inode_init_ts(inode);296	ufsi->i_flags = UFS_I(dir)->i_flags;297	ufsi->i_lastfrag = 0;298	ufsi->i_shadow = 0;299	ufsi->i_osync = 0;300	ufsi->i_oeftflag = 0;301	ufsi->i_dir_start_lookup = 0;302	memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1));303	if (insert_inode_locked(inode) < 0) {304		err = -EIO;305		goto failed;306	}307	mark_inode_dirty(inode);308 309	if (uspi->fs_magic == UFS2_MAGIC) {310		struct buffer_head *bh;311		struct ufs2_inode *ufs2_inode;312 313		/*314		 * setup birth date, we do it here because of there is no sense315		 * to hold it in struct ufs_inode_info, and lose 64 bit316		 */317		bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino));318		if (!bh) {319			ufs_warning(sb, "ufs_read_inode",320				    "unable to read inode %lu\n",321				    inode->i_ino);322			err = -EIO;323			goto fail_remove_inode;324		}325		lock_buffer(bh);326		ufs2_inode = (struct ufs2_inode *)bh->b_data;327		ufs2_inode += ufs_inotofsbo(inode->i_ino);328		ktime_get_real_ts64(&ts);329		ufs2_inode->ui_birthtime = cpu_to_fs64(sb, ts.tv_sec);330		ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, ts.tv_nsec);331		mark_buffer_dirty(bh);332		unlock_buffer(bh);333		if (sb->s_flags & SB_SYNCHRONOUS)334			sync_dirty_buffer(bh);335		brelse(bh);336	}337	mutex_unlock(&sbi->s_lock);338 339	UFSD("allocating inode %lu\n", inode->i_ino);340	UFSD("EXIT\n");341	return inode;342 343fail_remove_inode:344	mutex_unlock(&sbi->s_lock);345	clear_nlink(inode);346	discard_new_inode(inode);347	UFSD("EXIT (FAILED): err %d\n", err);348	return ERR_PTR(err);349failed:350	mutex_unlock(&sbi->s_lock);351	make_bad_inode(inode);352	iput (inode);353	UFSD("EXIT (FAILED): err %d\n", err);354	return ERR_PTR(err);355}356