xfs_bmap.c

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/*
 * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
 * Mountain View, CA  94043, or:
 *
 * http://www.sgi.com
 *
 * For further information regarding this notice, see:
 *
 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
 */

#include "xfs.h"

#include "xfs_macros.h"
#include "xfs_types.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_alloc_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_attr_sf.h"
#include "xfs_dir_sf.h"
#include "xfs_dir2_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode_item.h"
#include "xfs_inode.h"
#include "xfs_itable.h"
#include "xfs_extfree_item.h"
#include "xfs_alloc.h"
#include "xfs_bmap.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_da_btree.h"
#include "xfs_dir_leaf.h"
#include "xfs_bit.h"
#include "xfs_rw.h"
#include "xfs_quota.h"
#include "xfs_trans_space.h"
#include "xfs_buf_item.h"


#ifdef DEBUG
STATIC void
xfs_bmap_check_leaf_extents(xfs_btree_cur_t *cur, xfs_inode_t *ip, int whichfork);
#endif

kmem_zone_t		*xfs_bmap_free_item_zone;

/*
 * Prototypes for internal bmap routines.
 */


/*
 * Called from xfs_bmap_add_attrfork to handle extents format files.
 */
STATIC int					/* error */
xfs_bmap_add_attrfork_extents(
	xfs_trans_t		*tp,		/* transaction pointer */
	xfs_inode_t		*ip,		/* incore inode pointer */
	xfs_fsblock_t		*firstblock,	/* first block allocated */
	xfs_bmap_free_t		*flist,		/* blocks to free at commit */
	int			*flags);	/* inode logging flags */

/*
 * Called from xfs_bmap_add_attrfork to handle local format files.
 */
STATIC int					/* error */
xfs_bmap_add_attrfork_local(
	xfs_trans_t		*tp,		/* transaction pointer */
	xfs_inode_t		*ip,		/* incore inode pointer */
	xfs_fsblock_t		*firstblock,	/* first block allocated */
	xfs_bmap_free_t		*flist,		/* blocks to free at commit */
	int			*flags);	/* inode logging flags */

/*
 * Called by xfs_bmapi to update extent list structure and the btree
 * after allocating space (or doing a delayed allocation).
 */
STATIC int				/* error */
xfs_bmap_add_extent(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_extnum_t		idx,	/* extent number to update/insert */
	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
	xfs_bmbt_irec_t		*new,	/* new data to put in extent list */
	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
	int			*logflagsp, /* inode logging flags */
	int			whichfork, /* data or attr fork */
	int			rsvd);	/* OK to allocate reserved blocks */

/*
 * Called by xfs_bmap_add_extent to handle cases converting a delayed
 * allocation to a real allocation.
 */
STATIC int				/* error */
xfs_bmap_add_extent_delay_real(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_extnum_t		idx,	/* extent number to update/insert */
	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
	xfs_bmbt_irec_t		*new,	/* new data to put in extent list */
	xfs_filblks_t		*dnew,	/* new delayed-alloc indirect blocks */
	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
	int			*logflagsp, /* inode logging flags */
	int			rsvd);	/* OK to allocate reserved blocks */

/*
 * Called by xfs_bmap_add_extent to handle cases converting a hole
 * to a delayed allocation.
 */
STATIC int				/* error */
xfs_bmap_add_extent_hole_delay(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_extnum_t		idx,	/* extent number to update/insert */
	xfs_btree_cur_t		*cur,	/* if null, not a btree */
	xfs_bmbt_irec_t		*new,	/* new data to put in extent list */
	int			*logflagsp,/* inode logging flags */
	int			rsvd);	/* OK to allocate reserved blocks */

/*
 * Called by xfs_bmap_add_extent to handle cases converting a hole
 * to a real allocation.
 */
STATIC int				/* error */
xfs_bmap_add_extent_hole_real(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_extnum_t		idx,	/* extent number to update/insert */
	xfs_btree_cur_t		*cur,	/* if null, not a btree */
	xfs_bmbt_irec_t		*new,	/* new data to put in extent list */
	int			*logflagsp, /* inode logging flags */
	int			whichfork); /* data or attr fork */

/*
 * Called by xfs_bmap_add_extent to handle cases converting an unwritten
 * allocation to a real allocation or vice versa.
 */
STATIC int				/* error */
xfs_bmap_add_extent_unwritten_real(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_extnum_t		idx,	/* extent number to update/insert */
	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
	xfs_bmbt_irec_t		*new,	/* new data to put in extent list */
	int			*logflagsp); /* inode logging flags */

/*
 * xfs_bmap_alloc is called by xfs_bmapi to allocate an extent for a file.
 * It figures out where to ask the underlying allocator to put the new extent.
 */
STATIC int				/* error */
xfs_bmap_alloc(
	xfs_bmalloca_t		*ap);	/* bmap alloc argument struct */

/*
 * Transform a btree format file with only one leaf node, where the
 * extents list will fit in the inode, into an extents format file.
 * Since the extent list is already in-core, all we have to do is
 * give up the space for the btree root and pitch the leaf block.
 */
STATIC int				/* error */
xfs_bmap_btree_to_extents(
	xfs_trans_t		*tp,	/* transaction pointer */
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			*logflagsp, /* inode logging flags */
	int			whichfork); /* data or attr fork */

#ifdef DEBUG
/*
 * Check that the extents list for the inode ip is in the right order.
 */
STATIC void
xfs_bmap_check_extents(
	xfs_inode_t		*ip,		/* incore inode pointer */
	int			whichfork);	/* data or attr fork */
#endif

/*
 * Called by xfs_bmapi to update extent list structure and the btree
 * after removing space (or undoing a delayed allocation).
 */
STATIC int				/* error */
xfs_bmap_del_extent(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_trans_t		*tp,	/* current trans pointer */
	xfs_extnum_t		idx,	/* extent number to update/insert */
	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
	xfs_btree_cur_t		*cur,	/* if null, not a btree */
	xfs_bmbt_irec_t		*new,	/* new data to put in extent list */
	int			*logflagsp,/* inode logging flags */
	int			whichfork, /* data or attr fork */
	int			rsvd);	 /* OK to allocate reserved blocks */

/*
 * Remove the entry "free" from the free item list.  Prev points to the
 * previous entry, unless "free" is the head of the list.
 */
STATIC void
xfs_bmap_del_free(
	xfs_bmap_free_t		*flist,	/* free item list header */
	xfs_bmap_free_item_t	*prev,	/* previous item on list, if any */
	xfs_bmap_free_item_t	*free);	/* list item to be freed */

/*
 * Remove count entries from the extents array for inode "ip", starting
 * at index "idx".  Copies the remaining items down over the deleted ones,
 * and gives back the excess memory.
 */
STATIC void
xfs_bmap_delete_exlist(
	xfs_inode_t	*ip,		/* incode inode pointer */
	xfs_extnum_t	idx,		/* starting delete index */
	xfs_extnum_t	count,		/* count of items to delete */
	int		whichfork);	/* data or attr fork */

/*
 * Convert an extents-format file into a btree-format file.
 * The new file will have a root block (in the inode) and a single child block.
 */
STATIC int					/* error */
xfs_bmap_extents_to_btree(
	xfs_trans_t		*tp,		/* transaction pointer */
	xfs_inode_t		*ip,		/* incore inode pointer */
	xfs_fsblock_t		*firstblock,	/* first-block-allocated */
	xfs_bmap_free_t		*flist,		/* blocks freed in xaction */
	xfs_btree_cur_t		**curp,		/* cursor returned to caller */
	int			wasdel,		/* converting a delayed alloc */
	int			*logflagsp,	/* inode logging flags */
	int			whichfork);	/* data or attr fork */

/*
 * Insert new item(s) in the extent list for inode "ip".
 * Count new items are inserted at offset idx.
 */
STATIC void
xfs_bmap_insert_exlist(
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_extnum_t	idx,		/* starting index of new items */
	xfs_extnum_t	count,		/* number of inserted items */
	xfs_bmbt_irec_t	*new,		/* items to insert */
	int		whichfork);	/* data or attr fork */

/*
 * Convert a local file to an extents file.
 * This code is sort of bogus, since the file data needs to get
 * logged so it won't be lost.  The bmap-level manipulations are ok, though.
 */
STATIC int				/* error */
xfs_bmap_local_to_extents(
	xfs_trans_t	*tp,		/* transaction pointer */
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_fsblock_t	*firstblock,	/* first block allocated in xaction */
	xfs_extlen_t	total,		/* total blocks needed by transaction */
	int		*logflagsp,	/* inode logging flags */
	int		whichfork);	/* data or attr fork */

/*
 * Search the extents list for the inode, for the extent containing bno.
 * If bno lies in a hole, point to the next entry.  If bno lies past eof,
 * *eofp will be set, and *prevp will contain the last entry (null if none).
 * Else, *lastxp will be set to the index of the found
 * entry; *gotp will contain the entry.
 */
STATIC xfs_bmbt_rec_t *			/* pointer to found extent entry */
xfs_bmap_search_extents(
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_fileoff_t	bno,		/* block number searched for */
	int		whichfork,	/* data or attr fork */
	int		*eofp,		/* out: end of file found */
	xfs_extnum_t	*lastxp,	/* out: last extent index */
	xfs_bmbt_irec_t	*gotp,		/* out: extent entry found */
	xfs_bmbt_irec_t	*prevp);	/* out: previous extent entry found */

#ifdef XFS_BMAP_TRACE
/*
 * Add a bmap trace buffer entry.  Base routine for the others.
 */
STATIC void
xfs_bmap_trace_addentry(
	int		opcode,		/* operation */
	char		*fname,		/* function name */
	char		*desc,		/* operation description */
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_extnum_t	idx,		/* index of entry(ies) */
	xfs_extnum_t	cnt,		/* count of entries, 1 or 2 */
	xfs_bmbt_rec_t	*r1,		/* first record */
	xfs_bmbt_rec_t	*r2,		/* second record or null */
	int		whichfork);	/* data or attr fork */

/*
 * Add bmap trace entry prior to a call to xfs_bmap_delete_exlist.
 */
STATIC void
xfs_bmap_trace_delete(
	char		*fname,		/* function name */
	char		*desc,		/* operation description */
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_extnum_t	idx,		/* index of entry(entries) deleted */
	xfs_extnum_t	cnt,		/* count of entries deleted, 1 or 2 */
	int		whichfork);	/* data or attr fork */

/*
 * Add bmap trace entry prior to a call to xfs_bmap_insert_exlist, or
 * reading in the extents list from the disk (in the btree).
 */
STATIC void
xfs_bmap_trace_insert(
	char		*fname,		/* function name */
	char		*desc,		/* operation description */
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_extnum_t	idx,		/* index of entry(entries) inserted */
	xfs_extnum_t	cnt,		/* count of entries inserted, 1 or 2 */
	xfs_bmbt_irec_t	*r1,		/* inserted record 1 */
	xfs_bmbt_irec_t	*r2,		/* inserted record 2 or null */
	int		whichfork);	/* data or attr fork */

/*
 * Add bmap trace entry after updating an extent list entry in place.
 */
STATIC void
xfs_bmap_trace_post_update(
	char		*fname,		/* function name */
	char		*desc,		/* operation description */
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_extnum_t	idx,		/* index of entry updated */
	int		whichfork);	/* data or attr fork */

/*
 * Add bmap trace entry prior to updating an extent list entry in place.
 */
STATIC void
xfs_bmap_trace_pre_update(
	char		*fname,		/* function name */
	char		*desc,		/* operation description */
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_extnum_t	idx,		/* index of entry to be updated */
	int		whichfork);	/* data or attr fork */

#else
#define	xfs_bmap_trace_delete(f,d,ip,i,c,w)
#define	xfs_bmap_trace_insert(f,d,ip,i,c,r1,r2,w)
#define	xfs_bmap_trace_post_update(f,d,ip,i,w)
#define	xfs_bmap_trace_pre_update(f,d,ip,i,w)
#endif	/* XFS_BMAP_TRACE */

/*
 * Compute the worst-case number of indirect blocks that will be used
 * for ip's delayed extent of length "len".
 */
STATIC xfs_filblks_t
xfs_bmap_worst_indlen(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_filblks_t		len);	/* delayed extent length */

#ifdef DEBUG
/*
 * Perform various validation checks on the values being returned
 * from xfs_bmapi().
 */
STATIC void
xfs_bmap_validate_ret(
	xfs_fileoff_t		bno,
	xfs_filblks_t		len,
	int			flags,
	xfs_bmbt_irec_t		*mval,
	int			nmap,
	int			ret_nmap);
#else
#define	xfs_bmap_validate_ret(bno,len,flags,mval,onmap,nmap)
#endif /* DEBUG */

#if defined(XFS_RW_TRACE)
STATIC void
xfs_bunmap_trace(
	xfs_inode_t		*ip,
	xfs_fileoff_t		bno,
	xfs_filblks_t		len,
	int			flags,
	inst_t			*ra);
#else