/* *  linux/fs/ufs/ialloc.c * * Copyright (c) 1998 * Daniel Pirkl <daniel.pirkl@email.cz> * Charles University, Faculty of Mathematics and Physics * *  from * *  linux/fs/ext2/ialloc.c * * Copyright (C) 1992, 1993, 1994, 1995 * Remy Card (card@masi.ibp.fr) * Laboratoire MASI - Institut Blaise Pascal * Universite Pierre et Marie Curie (Paris VI) * *  BSD ufs-inspired inode and directory allocation by  *  Stephen Tweedie (sct@dcs.ed.ac.uk), 1993 *  Big-endian to little-endian byte-swapping/bitmaps by *        David S. Miller (davem@caip.rutgers.edu), 1995 */ #include <linux/fs.h>#include <linux/ufs_fs.h>#include <linux/time.h>#include <linux/stat.h>#include <linux/string.h>#include <linux/quotaops.h>#include <linux/buffer_head.h>#include <linux/sched.h>#include <linux/bitops.h>#include <asm/byteorder.h> #include "swab.h"#include "util.h" #undef UFS_IALLOC_DEBUG #ifdef UFS_IALLOC_DEBUG#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;#else#define UFSD(x)#endif /* * NOTE! When we get the inode, we're the only people * that have access to it, and as such there are no * race conditions we have to worry about. The inode * is not on the hash-lists, and it cannot be reached * through the filesystem because the directory entry * has been deleted earlier. * * HOWEVER: we must make sure that we get no aliases, * which means that we have to call "clear_inode()" * _before_ we mark the inode not in use in the inode * bitmaps. Otherwise a newly created file might use * the same inode number (not actually the same pointer * though), and then we'd have two inodes sharing the * same inode number and space on the harddisk. */void ufs_free_inode (struct inode * inode){	struct super_block * sb;	struct ufs_sb_private_info * uspi;	struct ufs_super_block_first * usb1;	struct ufs_cg_private_info * ucpi;	struct ufs_cylinder_group * ucg;	int is_directory;	unsigned ino, cg, bit;		UFSD(("ENTER, ino %lu\n", inode->i_ino)) 	sb = inode->i_sb;	uspi = UFS_SB(sb)->s_uspi;	usb1 = ubh_get_usb_first(uspi);		ino = inode->i_ino; 	lock_super (sb); 	if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {		ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);		unlock_super (sb);		return;	}		cg = ufs_inotocg (ino);	bit = ufs_inotocgoff (ino);	ucpi = ufs_load_cylinder (sb, cg);	if (!ucpi) {		unlock_super (sb);		return;	}	ucg = ubh_get_ucg(UCPI_UBH);	if (!ufs_cg_chkmagic(sb, ucg))		ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number"); 	ucg->cg_time = cpu_to_fs32(sb, get_seconds()); 	is_directory = S_ISDIR(inode->i_mode); 	DQUOT_FREE_INODE(inode);	DQUOT_DROP(inode); 	clear_inode (inode); 	if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))		ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino);	else {		ubh_clrbit (UCPI_UBH, ucpi->c_iusedoff, bit);		if (ino < ucpi->c_irotor)			ucpi->c_irotor = ino;		fs32_add(sb, &ucg->cg_cs.cs_nifree, 1);		fs32_add(sb, &usb1->fs_cstotal.cs_nifree, 1);		fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1); 		if (is_directory) {			fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1);			fs32_sub(sb, &usb1->fs_cstotal.cs_ndir, 1);			fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1);		}	} 	ubh_mark_buffer_dirty (USPI_UBH);	ubh_mark_buffer_dirty (UCPI_UBH);	if (sb->s_flags & MS_SYNCHRONOUS) {		ubh_ll_rw_block (SWRITE, 1, (struct ufs_buffer_head **) &ucpi);		ubh_wait_on_buffer (UCPI_UBH);	}		sb->s_dirt = 1;	unlock_super (sb);	UFSD(("EXIT\n"))} /* * There are two policies for allocating an inode.  If the new inode is * a directory, then a forward search is made for a block group with both * free space and a low directory-to-inode ratio; if that fails, then of * the groups with above-average free space, that group with the fewest * directories already is chosen. * * For other inodes, search forward from the parent directory's block * group to find a free inode. */struct inode * ufs_new_inode(struct inode * dir, int mode){	struct super_block * sb;	struct ufs_sb_info * sbi;	struct ufs_sb_private_info * uspi;	struct ufs_super_block_first * usb1;	struct ufs_cg_private_info * ucpi;	struct ufs_cylinder_group * ucg;	struct inode * inode;	unsigned cg, bit, i, j, start;	struct ufs_inode_info *ufsi; 	UFSD(("ENTER\n"))		/* Cannot create files in a deleted directory */	if (!dir || !dir->i_nlink)		return ERR_PTR(-EPERM);	sb = dir->i_sb;	inode = new_inode(sb);	if (!inode)		return ERR_PTR(-ENOMEM);	ufsi = UFS_I(inode);	sbi = UFS_SB(sb);	uspi = sbi->s_uspi;	usb1 = ubh_get_usb_first(uspi); 	lock_super (sb); 	/*	 * Try to place the inode in its parent directory	 */	i = ufs_inotocg(dir->i_ino);	if (sbi->fs_cs(i).cs_nifree) {		cg = i;		goto cg_found;	} 	/*	 * Use a quadratic hash to find a group with a free inode	 */	for ( j = 1; j < uspi->s_ncg; j <<= 1 ) {		i += j;		if (i >= uspi->s_ncg)			i -= uspi->s_ncg;		if (sbi->fs_cs(i).cs_nifree) {			cg = i;			goto cg_found;		}	} 	/*	 * That failed: try linear search for a free inode	 */	i = ufs_inotocg(dir->i_ino) + 1;	for (j = 2; j < uspi->s_ncg; j++) {		i++;		if (i >= uspi->s_ncg)			i = 0;		if (sbi->fs_cs(i).cs_nifree) {			cg = i;			goto cg_found;		}	}		goto failed; cg_found:	ucpi = ufs_load_cylinder (sb, cg);	if (!ucpi)		goto failed;	ucg = ubh_get_ucg(UCPI_UBH);	if (!ufs_cg_chkmagic(sb, ucg)) 		ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number"); 	start = ucpi->c_irotor;	bit = ubh_find_next_zero_bit (UCPI_UBH, ucpi->c_iusedoff, uspi->s_ipg, start);	if (!(bit < uspi->s_ipg)) {		bit = ubh_find_first_zero_bit (UCPI_UBH, ucpi->c_iusedoff, start);		if (!(bit < start)) {			ufs_error (sb, "ufs_new_inode",			    "cylinder group %u corrupted - error in inode bitmap\n", cg);			goto failed;		}	}	UFSD(("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg))	if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))		ubh_setbit (UCPI_UBH, ucpi->c_iusedoff, bit);	else {		ufs_panic (sb, "ufs_new_inode", "internal error");		goto failed;	}		fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1);	fs32_sub(sb, &usb1->fs_cstotal.cs_nifree, 1);	fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1);		if (S_ISDIR(mode)) {		fs32_add(sb, &ucg->cg_cs.cs_ndir, 1);		fs32_add(sb, &usb1->fs_cstotal.cs_ndir, 1);		fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1);	} 	ubh_mark_buffer_dirty (USPI_UBH);	ubh_mark_buffer_dirty (UCPI_UBH);	if (sb->s_flags & MS_SYNCHRONOUS) {		ubh_ll_rw_block (SWRITE, 1, (struct ufs_buffer_head **) &ucpi);		ubh_wait_on_buffer (UCPI_UBH);	}	sb->s_dirt = 1; 	inode->i_mode = mode;	inode->i_uid = current->fsuid;	if (dir->i_mode & S_ISGID) {		inode->i_gid = dir->i_gid;		if (S_ISDIR(mode))			inode->i_mode |= S_ISGID;	} else		inode->i_gid = current->fsgid; 	inode->i_ino = cg * uspi->s_ipg + bit;	inode->i_blksize = PAGE_SIZE;	/* This is the optimal IO size (for stat), not the fs block size */	inode->i_blocks = 0;	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;	ufsi->i_flags = UFS_I(dir)->i_flags;	ufsi->i_lastfrag = 0;	ufsi->i_gen = 0;	ufsi->i_shadow = 0;	ufsi->i_osync = 0;	ufsi->i_oeftflag = 0;	memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); 	insert_inode_hash(inode);	mark_inode_dirty(inode); 	unlock_super (sb); 	if (DQUOT_ALLOC_INODE(inode)) {		DQUOT_DROP(inode);		inode->i_flags |= S_NOQUOTA;		inode->i_nlink = 0;		iput(inode);		return ERR_PTR(-EDQUOT);	} 	UFSD(("allocating inode %lu\n", inode->i_ino))	UFSD(("EXIT\n"))	return inode; failed:	unlock_super (sb);	make_bad_inode(inode);	iput (inode);	UFSD(("EXIT (FAILED)\n"))	return ERR_PTR(-ENOSPC);}