super.c

ARM 嵌入式 系统 设计与实例开发 实验教材 二源码

		UFSD(("ufstype=44bsd\n"))
		uspi->s_fsize = block_size = 512;
		uspi->s_fmask = ~(512 - 1);
		uspi->s_fshift = 9;
		uspi->s_sbsize = super_block_size = 1536;
		uspi->s_sbbase = 0;
		flags |= UFS_DE_44BSD | UFS_UID_44BSD | UFS_ST_44BSD | UFS_CG_44BSD;
		break;
		
	case UFS_MOUNT_UFSTYPE_SUN:
		UFSD(("ufstype=sun\n"))
		uspi->s_fsize = block_size = 1024;
		uspi->s_fmask = ~(1024 - 1);
		uspi->s_fshift = 10;
		uspi->s_sbsize = super_block_size = 2048;
		uspi->s_sbbase = 0;
		uspi->s_maxsymlinklen = 56;
		flags |= UFS_DE_OLD | UFS_UID_EFT | UFS_ST_SUN | UFS_CG_SUN;
		break;

	case UFS_MOUNT_UFSTYPE_SUNx86:
		UFSD(("ufstype=sunx86\n"))
		uspi->s_fsize = block_size = 1024;
		uspi->s_fmask = ~(1024 - 1);
		uspi->s_fshift = 10;
		uspi->s_sbsize = super_block_size = 2048;
		uspi->s_sbbase = 0;
		uspi->s_maxsymlinklen = 56;
		flags |= UFS_DE_OLD | UFS_UID_EFT | UFS_ST_SUNx86 | UFS_CG_SUN;
		break;

	case UFS_MOUNT_UFSTYPE_OLD:
		UFSD(("ufstype=old\n"))
		uspi->s_fsize = block_size = 1024;
		uspi->s_fmask = ~(1024 - 1);
		uspi->s_fshift = 10;
		uspi->s_sbsize = super_block_size = 2048;
		uspi->s_sbbase = 0;
		flags |= UFS_DE_OLD | UFS_UID_OLD | UFS_ST_OLD | UFS_CG_OLD;
		if (!(sb->s_flags & MS_RDONLY)) {
			printk(KERN_INFO "ufstype=old is supported read-only\n"); 
			sb->s_flags |= MS_RDONLY;
		}
		break;
	
	case UFS_MOUNT_UFSTYPE_NEXTSTEP:
		UFSD(("ufstype=nextstep\n"))
		uspi->s_fsize = block_size = 1024;
		uspi->s_fmask = ~(1024 - 1);
		uspi->s_fshift = 10;
		uspi->s_sbsize = super_block_size = 2048;
		uspi->s_sbbase = 0;
		flags |= UFS_DE_OLD | UFS_UID_OLD | UFS_ST_OLD | UFS_CG_OLD;
		if (!(sb->s_flags & MS_RDONLY)) {
			printk(KERN_INFO "ufstype=nextstep is supported read-only\n");
			sb->s_flags |= MS_RDONLY;
		}
		break;
	
	case UFS_MOUNT_UFSTYPE_NEXTSTEP_CD:
		UFSD(("ufstype=nextstep-cd\n"))
		uspi->s_fsize = block_size = 2048;
		uspi->s_fmask = ~(2048 - 1);
		uspi->s_fshift = 11;
		uspi->s_sbsize = super_block_size = 2048;
		uspi->s_sbbase = 0;
		flags |= UFS_DE_OLD | UFS_UID_OLD | UFS_ST_OLD | UFS_CG_OLD;
		if (!(sb->s_flags & MS_RDONLY)) {
			printk(KERN_INFO "ufstype=nextstep-cd is supported read-only\n");
			sb->s_flags |= MS_RDONLY;
		}
		break;
	
	case UFS_MOUNT_UFSTYPE_OPENSTEP:
		UFSD(("ufstype=openstep\n"))
		uspi->s_fsize = block_size = 1024;
		uspi->s_fmask = ~(1024 - 1);
		uspi->s_fshift = 10;
		uspi->s_sbsize = super_block_size = 2048;
		uspi->s_sbbase = 0;
		flags |= UFS_DE_44BSD | UFS_UID_44BSD | UFS_ST_44BSD | UFS_CG_44BSD;
		if (!(sb->s_flags & MS_RDONLY)) {
			printk(KERN_INFO "ufstype=openstep is supported read-only\n");
			sb->s_flags |= MS_RDONLY;
		}
		break;
	
	case UFS_MOUNT_UFSTYPE_HP:
		UFSD(("ufstype=hp\n"))
		uspi->s_fsize = block_size = 1024;
		uspi->s_fmask = ~(1024 - 1);
		uspi->s_fshift = 10;
		uspi->s_sbsize = super_block_size = 2048;
		uspi->s_sbbase = 0;
		flags |= UFS_DE_OLD | UFS_UID_OLD | UFS_ST_OLD | UFS_CG_OLD;
		if (!(sb->s_flags & MS_RDONLY)) {
			printk(KERN_INFO "ufstype=hp is supported read-only\n");
			sb->s_flags |= MS_RDONLY;
 		}
 		break;
	default:
		printk("unknown ufstype\n");
		goto failed;
	}
	
again:	
	set_blocksize (sb->s_dev, block_size);
	sb->s_blocksize = block_size;

	/*
	 * read ufs super block from device
	 */
	ubh = ubh_bread_uspi (uspi, sb, uspi->s_sbbase + UFS_SBLOCK/block_size, super_block_size);
	if (!ubh) 
		goto failed;
	
	usb1 = ubh_get_usb_first(USPI_UBH);
	usb2 = ubh_get_usb_second(USPI_UBH);
	usb3 = ubh_get_usb_third(USPI_UBH);

	/*
	 * Check ufs magic number
	 */
	switch (__constant_le32_to_cpu(usb3->fs_magic)) {
		case UFS_MAGIC:
		case UFS_MAGIC_LFN:
	        case UFS_MAGIC_FEA:
	        case UFS_MAGIC_4GB:
			sb->u.ufs_sb.s_bytesex = BYTESEX_LE;
			goto magic_found;
	}
	switch (__constant_be32_to_cpu(usb3->fs_magic)) {
		case UFS_MAGIC:
		case UFS_MAGIC_LFN:
	        case UFS_MAGIC_FEA:
	        case UFS_MAGIC_4GB:
			sb->u.ufs_sb.s_bytesex = BYTESEX_BE;
			goto magic_found;
	}

	if ((((sb->u.ufs_sb.s_mount_opt & UFS_MOUNT_UFSTYPE) == UFS_MOUNT_UFSTYPE_NEXTSTEP) 
	  || ((sb->u.ufs_sb.s_mount_opt & UFS_MOUNT_UFSTYPE) == UFS_MOUNT_UFSTYPE_NEXTSTEP_CD) 
	  || ((sb->u.ufs_sb.s_mount_opt & UFS_MOUNT_UFSTYPE) == UFS_MOUNT_UFSTYPE_OPENSTEP)) 
	  && uspi->s_sbbase < 256) {
		ubh_brelse_uspi(uspi);
		ubh = NULL;
		uspi->s_sbbase += 8;
		goto again;
	}
	printk("ufs_read_super: bad magic number\n");
	goto failed;

magic_found:
	/*
	 * Check block and fragment sizes
	 */
	uspi->s_bsize = fs32_to_cpu(sb, usb1->fs_bsize);
	uspi->s_fsize = fs32_to_cpu(sb, usb1->fs_fsize);
	uspi->s_sbsize = fs32_to_cpu(sb, usb1->fs_sbsize);
	uspi->s_fmask = fs32_to_cpu(sb, usb1->fs_fmask);
	uspi->s_fshift = fs32_to_cpu(sb, usb1->fs_fshift);

	if (uspi->s_bsize != 4096 && uspi->s_bsize != 8192 
	  && uspi->s_bsize != 32768) {
		printk("ufs_read_super: fs_bsize %u != {4096, 8192, 32768}\n", uspi->s_bsize);
		goto failed;
	}
	if (uspi->s_fsize != 512 && uspi->s_fsize != 1024 
	  && uspi->s_fsize != 2048 && uspi->s_fsize != 4096) {
		printk("ufs_read_super: fs_fsize %u != {512, 1024, 2048. 4096}\n", uspi->s_fsize);
		goto failed;
	}
	if (uspi->s_fsize != block_size || uspi->s_sbsize != super_block_size) {
		ubh_brelse_uspi(uspi);
		ubh = NULL;
		block_size = uspi->s_fsize;
		super_block_size = uspi->s_sbsize;
		UFSD(("another value of block_size or super_block_size %u, %u\n", block_size, super_block_size))
		goto again;
	}

#ifdef UFS_SUPER_DEBUG_MORE
	ufs_print_super_stuff(sb, usb1, usb2, usb3);
#endif

	/*
	 * Check, if file system was correctly unmounted.
	 * If not, make it read only.
	 */
	if (((flags & UFS_ST_MASK) == UFS_ST_44BSD) ||
	  ((flags & UFS_ST_MASK) == UFS_ST_OLD) ||
	  (((flags & UFS_ST_MASK) == UFS_ST_SUN || 
	  (flags & UFS_ST_MASK) == UFS_ST_SUNx86) && 
	  (ufs_get_fs_state(sb, usb1, usb3) == (UFS_FSOK - fs32_to_cpu(sb, usb1->fs_time))))) {
		switch(usb1->fs_clean) {
		case UFS_FSCLEAN:
			UFSD(("fs is clean\n"))
			break;
		case UFS_FSSTABLE:
			UFSD(("fs is stable\n"))
			break;
		case UFS_FSOSF1:
			UFSD(("fs is DEC OSF/1\n"))
			break;
		case UFS_FSACTIVE:
			printk("ufs_read_super: fs is active\n");
			sb->s_flags |= MS_RDONLY;
			break;
		case UFS_FSBAD:
			printk("ufs_read_super: fs is bad\n");
			sb->s_flags |= MS_RDONLY;
			break;
		default:
			printk("ufs_read_super: can't grok fs_clean 0x%x\n", usb1->fs_clean);
			sb->s_flags |= MS_RDONLY;
			break;
		}
	}
	else {
		printk("ufs_read_super: fs needs fsck\n");
		sb->s_flags |= MS_RDONLY;
	}

	/*
	 * Read ufs_super_block into internal data structures
	 */
	sb->s_blocksize = fs32_to_cpu(sb, usb1->fs_fsize);
	sb->s_blocksize_bits = fs32_to_cpu(sb, usb1->fs_fshift);
	sb->s_op = &ufs_super_ops;
	sb->dq_op = NULL; /***/
	sb->s_magic = fs32_to_cpu(sb, usb3->fs_magic);

	uspi->s_sblkno = fs32_to_cpu(sb, usb1->fs_sblkno);
	uspi->s_cblkno = fs32_to_cpu(sb, usb1->fs_cblkno);
	uspi->s_iblkno = fs32_to_cpu(sb, usb1->fs_iblkno);
	uspi->s_dblkno = fs32_to_cpu(sb, usb1->fs_dblkno);
	uspi->s_cgoffset = fs32_to_cpu(sb, usb1->fs_cgoffset);
	uspi->s_cgmask = fs32_to_cpu(sb, usb1->fs_cgmask);
	uspi->s_size = fs32_to_cpu(sb, usb1->fs_size);
	uspi->s_dsize = fs32_to_cpu(sb, usb1->fs_dsize);
	uspi->s_ncg = fs32_to_cpu(sb, usb1->fs_ncg);
	/* s_bsize already set */
	/* s_fsize already set */
	uspi->s_fpb = fs32_to_cpu(sb, usb1->fs_frag);
	uspi->s_minfree = fs32_to_cpu(sb, usb1->fs_minfree);
	uspi->s_bmask = fs32_to_cpu(sb, usb1->fs_bmask);
	uspi->s_fmask = fs32_to_cpu(sb, usb1->fs_fmask);
	uspi->s_bshift = fs32_to_cpu(sb, usb1->fs_bshift);
	uspi->s_fshift = fs32_to_cpu(sb, usb1->fs_fshift);
	uspi->s_fpbshift = fs32_to_cpu(sb, usb1->fs_fragshift);
	uspi->s_fsbtodb = fs32_to_cpu(sb, usb1->fs_fsbtodb);
	/* s_sbsize already set */
	uspi->s_csmask = fs32_to_cpu(sb, usb1->fs_csmask);
	uspi->s_csshift = fs32_to_cpu(sb, usb1->fs_csshift);
	uspi->s_nindir = fs32_to_cpu(sb, usb1->fs_nindir);
	uspi->s_inopb = fs32_to_cpu(sb, usb1->fs_inopb);
	uspi->s_nspf = fs32_to_cpu(sb, usb1->fs_nspf);
	uspi->s_npsect = ufs_get_fs_npsect(sb, usb1, usb3);
	uspi->s_interleave = fs32_to_cpu(sb, usb1->fs_interleave);
	uspi->s_trackskew = fs32_to_cpu(sb, usb1->fs_trackskew);
	uspi->s_csaddr = fs32_to_cpu(sb, usb1->fs_csaddr);
	uspi->s_cssize = fs32_to_cpu(sb, usb1->fs_cssize);
	uspi->s_cgsize = fs32_to_cpu(sb, usb1->fs_cgsize);
	uspi->s_ntrak = fs32_to_cpu(sb, usb1->fs_ntrak);
	uspi->s_nsect = fs32_to_cpu(sb, usb1->fs_nsect);
	uspi->s_spc = fs32_to_cpu(sb, usb1->fs_spc);
	uspi->s_ipg = fs32_to_cpu(sb, usb1->fs_ipg);
	uspi->s_fpg = fs32_to_cpu(sb, usb1->fs_fpg);
	uspi->s_cpc = fs32_to_cpu(sb, usb2->fs_cpc);
	uspi->s_contigsumsize = fs32_to_cpu(sb, usb3->fs_u2.fs_44.fs_contigsumsize);
	uspi->s_qbmask = ufs_get_fs_qbmask(sb, usb3);
	uspi->s_qfmask = ufs_get_fs_qfmask(sb, usb3);
	uspi->s_postblformat = fs32_to_cpu(sb, usb3->fs_postblformat);
	uspi->s_nrpos = fs32_to_cpu(sb, usb3->fs_nrpos);
	uspi->s_postbloff = fs32_to_cpu(sb, usb3->fs_postbloff);
	uspi->s_rotbloff = fs32_to_cpu(sb, usb3->fs_rotbloff);

	/*
	 * Compute another frequently used values
	 */
	uspi->s_fpbmask = uspi->s_fpb - 1;
	uspi->s_apbshift = uspi->s_bshift - 2;
	uspi->s_2apbshift = uspi->s_apbshift * 2;
	uspi->s_3apbshift = uspi->s_apbshift * 3;
	uspi->s_apb = 1 << uspi->s_apbshift;
	uspi->s_2apb = 1 << uspi->s_2apbshift;
	uspi->s_3apb = 1 << uspi->s_3apbshift;
	uspi->s_apbmask = uspi->s_apb - 1;
	uspi->s_nspfshift = uspi->s_fshift - UFS_SECTOR_BITS;
	uspi->s_nspb = uspi->s_nspf << uspi->s_fpbshift;
	uspi->s_inopf = uspi->s_inopb >> uspi->s_fpbshift;
	uspi->s_bpf = uspi->s_fsize << 3;
	uspi->s_bpfshift = uspi->s_fshift + 3;
	uspi->s_bpfmask = uspi->s_bpf - 1;
	if ((sb->u.ufs_sb.s_mount_opt & UFS_MOUNT_UFSTYPE) ==
	    UFS_MOUNT_UFSTYPE_44BSD)
		uspi->s_maxsymlinklen =
		    fs32_to_cpu(sb, usb3->fs_u2.fs_44.fs_maxsymlinklen);
	
	sb->u.ufs_sb.s_flags = flags;

	inode = iget(sb, UFS_ROOTINO);
	if (!inode || is_bad_inode(inode))
		goto failed;
	sb->s_root = d_alloc_root(inode);
	if (!sb->s_root)
		goto dalloc_failed;


	/*
	 * Read cylinder group structures
	 */
	if (!(sb->s_flags & MS_RDONLY))
		if (!ufs_read_cylinder_structures(sb))
			goto failed;

	UFSD(("EXIT\n"))
	return(sb);

dalloc_failed:
	iput(inode);
failed:
	if (ubh) ubh_brelse_uspi (uspi);
	if (uspi) kfree (uspi);
	UFSD(("EXIT (FAILED)\n"))
	return(NULL);
}

void ufs_write_super (struct super_block * sb) {
	struct ufs_sb_private_info * uspi;
	struct ufs_super_block_first * usb1;
	struct ufs_super_block_third * usb3;
	unsigned flags;

	UFSD(("ENTER\n"))
	flags = sb->u.ufs_sb.s_flags;
	uspi = sb->u.ufs_sb.s_uspi;
	usb1 = ubh_get_usb_first(USPI_UBH);
	usb3 = ubh_get_usb_third(USPI_UBH);

	if (!(sb->s_flags & MS_RDONLY)) {
		usb1->fs_time = cpu_to_fs32(sb, CURRENT_TIME);
		if ((flags & UFS_ST_MASK) == UFS_ST_SUN 
		  || (flags & UFS_ST_MASK) == UFS_ST_SUNx86)
			ufs_set_fs_state(sb, usb1, usb3,
					UFS_FSOK - fs32_to_cpu(sb, usb1->fs_time));
		ubh_mark_buffer_dirty (USPI_UBH);
	}
	sb->s_dirt = 0;
	UFSD(("EXIT\n"))
}

void ufs_put_super (struct super_block * sb)
{
	struct ufs_sb_private_info * uspi;
		
	UFSD(("ENTER\n"))

	uspi = sb->u.ufs_sb.s_uspi;

	if (!(sb->s_flags & MS_RDONLY))
		ufs_put_cylinder_structures (sb);
	
	ubh_brelse_uspi (uspi);
	kfree (sb->u.ufs_sb.s_uspi);
	return;
}


int ufs_remount (struct super_block * sb, int * mount_flags, char * data)
{
	struct ufs_sb_private_info * uspi;
	struct ufs_super_block_first * usb1;
	struct ufs_super_block_third * usb3;
	unsigned new_mount_opt, ufstype;
	unsigned flags;
	
	uspi = sb->u.ufs_sb.s_uspi;
	flags = sb->u.ufs_sb.s_flags;
	usb1 = ubh_get_usb_first(USPI_UBH);
	usb3 = ubh_get_usb_third(USPI_UBH);
	
	/*
	 * Allow the "check" option to be passed as a remount option.
	 * It is not possible to change ufstype option during remount
	 */
	ufstype = sb->u.ufs_sb.s_mount_opt & UFS_MOUNT_UFSTYPE;
	new_mount_opt = 0;
	ufs_set_opt (new_mount_opt, ONERROR_LOCK);
	if (!ufs_parse_options (data, &new_mount_opt))
		return -EINVAL;
	if (!(new_mount_opt & UFS_MOUNT_UFSTYPE)) {
		new_mount_opt |= ufstype;
	}
	else if ((new_mount_opt & UFS_MOUNT_UFSTYPE) != ufstype) {
		printk("ufstype can't be changed during remount\n");
		return -EINVAL;
	}

	if ((*mount_flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
		sb->u.ufs_sb.s_mount_opt = new_mount_opt;
		return 0;
	}
	
	/*
	 * fs was mouted as rw, remounting ro
	 */
	if (*mount_flags & MS_RDONLY) {
		ufs_put_cylinder_structures(sb);
		usb1->fs_time = cpu_to_fs32(sb, CURRENT_TIME);
		if ((flags & UFS_ST_MASK) == UFS_ST_SUN
		  || (flags & UFS_ST_MASK) == UFS_ST_SUNx86) 
			ufs_set_fs_state(sb, usb1, usb3,
				UFS_FSOK - fs32_to_cpu(sb, usb1->fs_time));
		ubh_mark_buffer_dirty (USPI_UBH);
		sb->s_dirt = 0;
		sb->s_flags |= MS_RDONLY;
	}
	/*
	 * fs was mounted as ro, remounting rw
	 */
	else {
#ifndef CONFIG_UFS_FS_WRITE
		printk("ufs was compiled with read-only support, "
		"can't be mounted as read-write\n");
		return -EINVAL;
#else
		if (ufstype != UFS_MOUNT_UFSTYPE_SUN && 
		    ufstype != UFS_MOUNT_UFSTYPE_44BSD &&
		    ufstype != UFS_MOUNT_UFSTYPE_SUNx86) {
			printk("this ufstype is read-only supported\n");
			return -EINVAL;
		}
		if (!ufs_read_cylinder_structures (sb)) {
			printk("failed during remounting\n");
			return -EPERM;
		}
		sb->s_flags &= ~MS_RDONLY;
#endif
	}
	sb->u.ufs_sb.s_mount_opt = new_mount_opt;
	return 0;
}

int ufs_statfs (struct super_block * sb, struct statfs * buf)
{
	struct ufs_sb_private_info * uspi;
	struct ufs_super_block_first * usb1;

	uspi = sb->u.ufs_sb.s_uspi;
	usb1 = ubh_get_usb_first (USPI_UBH);
	
	buf->f_type = UFS_MAGIC;
	buf->f_bsize = sb->s_blocksize;
	buf->f_blocks = uspi->s_dsize;
	buf->f_bfree = ufs_blkstofrags(fs32_to_cpu(sb, usb1->fs_cstotal.cs_nbfree)) +
		fs32_to_cpu(sb, usb1->fs_cstotal.cs_nffree);
	buf->f_bavail = (buf->f_bfree > ((buf->f_blocks / 100) * uspi->s_minfree))
		? (buf->f_bfree - ((buf->f_blocks / 100) * uspi->s_minfree)) : 0;
	buf->f_files = uspi->s_ncg * uspi->s_ipg;
	buf->f_ffree = fs32_to_cpu(sb, usb1->fs_cstotal.cs_nifree);
	buf->f_namelen = UFS_MAXNAMLEN;
	return 0;
}

static struct super_operations ufs_super_ops = {
	read_inode:	ufs_read_inode,
	write_inode:	ufs_write_inode,
	delete_inode:	ufs_delete_inode,
	put_super:	ufs_put_super,
	write_super:	ufs_write_super,
	statfs:		ufs_statfs,
	remount_fs:	ufs_remount,
};

static DECLARE_FSTYPE_DEV(ufs_fs_type, "ufs", ufs_read_super);

static int __init init_ufs_fs(void)
{
	return register_filesystem(&ufs_fs_type);
}

static void __exit exit_ufs_fs(void)
{
	unregister_filesystem(&ufs_fs_type);
}

EXPORT_NO_SYMBOLS;

module_init(init_ufs_fs)
module_exit(exit_ufs_fs)
MODULE_LICENSE("GPL");