131 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			131 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2000-2001 Christoph Hellwig.
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|  * All rights reserved.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions
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|  * are met:
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|  * 1. Redistributions of source code must retain the above copyright
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|  *    notice, this list of conditions, and the following disclaimer,
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|  *    without modification.
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|  * 2. The name of the author may not be used to endorse or promote products
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|  *    derived from this software without specific prior written permission.
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|  *
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|  * Alternatively, this software may be distributed under the terms of the
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|  * GNU General Public License ("GPL").
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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|  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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|  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
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|  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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|  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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|  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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|  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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|  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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|  * SUCH DAMAGE.
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|  */
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| 
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| /* 
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|  * Veritas filesystem driver - object location table support.
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|  */
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| #include <linux/fs.h>
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| #include <linux/buffer_head.h>
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| #include <linux/kernel.h>
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| 
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| #include "vxfs.h"
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| #include "vxfs_olt.h"
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| #include "vxfs_extern.h"
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| 
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| 
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| static inline void
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| vxfs_get_fshead(struct vxfs_oltfshead *fshp, struct vxfs_sb_info *infp)
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| {
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| 	BUG_ON(infp->vsi_fshino);
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| 	infp->vsi_fshino = fshp->olt_fsino[0];
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| }
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| 
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| static inline void
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| vxfs_get_ilist(struct vxfs_oltilist *ilistp, struct vxfs_sb_info *infp)
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| {
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| 	BUG_ON(infp->vsi_iext);
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| 	infp->vsi_iext = ilistp->olt_iext[0]; 
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| }
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| 
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| static inline u_long
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| vxfs_oblock(struct super_block *sbp, daddr_t block, u_long bsize)
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| {
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| 	BUG_ON(sbp->s_blocksize % bsize);
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| 	return (block * (sbp->s_blocksize / bsize));
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| }
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| 
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| 
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| /**
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|  * vxfs_read_olt - read olt
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|  * @sbp:	superblock of the filesystem
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|  * @bsize:	blocksize of the filesystem
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|  *
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|  * Description:
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|  *   vxfs_read_olt reads the olt of the filesystem described by @sbp
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|  *   into main memory and does some basic setup.
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|  *
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|  * Returns:
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|  *   Zero on success, else a negative error code.
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|  */
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| int
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| vxfs_read_olt(struct super_block *sbp, u_long bsize)
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| {
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| 	struct vxfs_sb_info	*infp = VXFS_SBI(sbp);
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| 	struct buffer_head	*bp;
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| 	struct vxfs_olt		*op;
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| 	char			*oaddr, *eaddr;
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| 
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| 
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| 	bp = sb_bread(sbp, vxfs_oblock(sbp, infp->vsi_oltext, bsize));
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| 	if (!bp || !bp->b_data)
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| 		goto fail;
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| 
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| 	op = (struct vxfs_olt *)bp->b_data;
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| 	if (op->olt_magic != VXFS_OLT_MAGIC) {
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| 		printk(KERN_NOTICE "vxfs: ivalid olt magic number\n");
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| 		goto fail;
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| 	}
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| 
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| 	/*
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| 	 * It is in theory possible that vsi_oltsize is > 1.
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| 	 * I've not seen any such filesystem yet and I'm lazy..  --hch
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| 	 */
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| 	if (infp->vsi_oltsize > 1) {
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| 		printk(KERN_NOTICE "vxfs: oltsize > 1 detected.\n");
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| 		printk(KERN_NOTICE "vxfs: please notify hch@infradead.org\n");
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| 		goto fail;
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| 	}
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| 
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| 	oaddr = bp->b_data + op->olt_size;
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| 	eaddr = bp->b_data + (infp->vsi_oltsize * sbp->s_blocksize);
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| 
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| 	while (oaddr < eaddr) {
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| 		struct vxfs_oltcommon	*ocp =
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| 			(struct vxfs_oltcommon *)oaddr;
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| 		
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| 		switch (ocp->olt_type) {
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| 		case VXFS_OLT_FSHEAD:
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| 			vxfs_get_fshead((struct vxfs_oltfshead *)oaddr, infp);
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| 			break;
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| 		case VXFS_OLT_ILIST:
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| 			vxfs_get_ilist((struct vxfs_oltilist *)oaddr, infp);
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| 			break;
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| 		}
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| 
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| 		oaddr += ocp->olt_size;
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| 	}
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| 
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| 	brelse(bp);
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| 	return 0;
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| 
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| fail:
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| 	brelse(bp);
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| 	return -EINVAL;
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| }
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