コード例 #1
0
ファイル: ialloc.c プロジェクト: 274914765/C
/*
 * 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;
    int err = -ENOSPC;

    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) {
        err = -EIO;
        goto failed;
    }
    ucg = ubh_get_ucg(UCPI_UBH(ucpi));
    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), ucpi->c_iusedoff, uspi->s_ipg, start);
    if (!(bit < uspi->s_ipg)) {
        bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start);
        if (!(bit < start)) {
            ufs_error (sb, "ufs_new_inode",
                "cylinder group %u corrupted - error in inode bitmap\n", cg);
            err = -EIO;
            goto failed;
        }
    }
    UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg);
    if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit))
        ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit);
    else {
        ufs_panic (sb, "ufs_new_inode", "internal error");
        err = -EIO;
        goto failed;
    }

    if (uspi->fs_magic == UFS2_MAGIC) {
        u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk);

        if (bit + uspi->s_inopb > initediblk &&
            initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk))
            ufs2_init_inodes_chunk(sb, ucpi, ucg);
    }

    fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1);
    uspi->cs_total.cs_nifree--;
    fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1);
    
    if (S_ISDIR(mode)) {
        fs32_add(sb, &ucg->cg_cs.cs_ndir, 1);
        uspi->cs_total.cs_ndir++;
        fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1);
    }
    ubh_mark_buffer_dirty (USPI_UBH(uspi));
    ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
    if (sb->s_flags & MS_SYNCHRONOUS) {
        ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi));
        ubh_wait_on_buffer (UCPI_UBH(ucpi));
    }
    sb->s_dirt = 1;

    inode->i_ino = cg * uspi->s_ipg + bit;
    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_blocks = 0;
    inode->i_generation = 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_shadow = 0;
    ufsi->i_osync = 0;
    ufsi->i_oeftflag = 0;
    ufsi->i_dir_start_lookup = 0;
    memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1));
    insert_inode_hash(inode);
    mark_inode_dirty(inode);

    if (uspi->fs_magic == UFS2_MAGIC) {
        struct buffer_head *bh;
        struct ufs2_inode *ufs2_inode;

        /*
         * setup birth date, we do it here because of there is no sense
         * to hold it in struct ufs_inode_info, and lose 64 bit
         */
        bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino));
        if (!bh) {
            ufs_warning(sb, "ufs_read_inode",
                    "unable to read inode %lu\n",
                    inode->i_ino);
            err = -EIO;
            goto fail_remove_inode;
        }
        lock_buffer(bh);
        ufs2_inode = (struct ufs2_inode *)bh->b_data;
        ufs2_inode += ufs_inotofsbo(inode->i_ino);
        ufs2_inode->ui_birthtime = cpu_to_fs64(sb, CURRENT_TIME.tv_sec);
        ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, CURRENT_TIME.tv_nsec);
        mark_buffer_dirty(bh);
        unlock_buffer(bh);
        if (sb->s_flags & MS_SYNCHRONOUS)
            sync_dirty_buffer(bh);
        brelse(bh);
    }

    unlock_super (sb);

    if (DQUOT_ALLOC_INODE(inode)) {
        DQUOT_DROP(inode);
        err = -EDQUOT;
        goto fail_without_unlock;
    }

    UFSD("allocating inode %lu\n", inode->i_ino);
    UFSD("EXIT\n");
    return inode;

fail_remove_inode:
    unlock_super(sb);
fail_without_unlock:
    inode->i_flags |= S_NOQUOTA;
    inode->i_nlink = 0;
    iput(inode);
    UFSD("EXIT (FAILED): err %d\n", err);
    return ERR_PTR(err);
failed:
    unlock_super (sb);
    make_bad_inode(inode);
    iput (inode);
    UFSD("EXIT (FAILED): err %d\n", err);
    return ERR_PTR(err);
}
コード例 #2
0
ファイル: ialloc.c プロジェクト: Antonio-Zhou/Linux-2.6.11
/*
 * 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_UBH);

	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_wait_on_buffer (UCPI_UBH);
		ubh_ll_rw_block (WRITE, 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);
}