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Diffstat (limited to 'fs/xfs/xfs_bmap.h')
-rw-r--r-- | fs/xfs/xfs_bmap.h | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/fs/xfs/xfs_bmap.h b/fs/xfs/xfs_bmap.h new file mode 100644 index 0000000..f1bc22f --- /dev/null +++ b/fs/xfs/xfs_bmap.h @@ -0,0 +1,379 @@ +/* + * Copyright (c) 2000-2003 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/ + */ +#ifndef __XFS_BMAP_H__ +#define __XFS_BMAP_H__ + +struct getbmap; +struct xfs_bmbt_irec; +struct xfs_inode; +struct xfs_mount; +struct xfs_trans; + +/* + * List of extents to be free "later". + * The list is kept sorted on xbf_startblock. + */ +typedef struct xfs_bmap_free_item +{ + xfs_fsblock_t xbfi_startblock;/* starting fs block number */ + xfs_extlen_t xbfi_blockcount;/* number of blocks in extent */ + struct xfs_bmap_free_item *xbfi_next; /* link to next entry */ +} xfs_bmap_free_item_t; + +/* + * Header for free extent list. + */ +typedef struct xfs_bmap_free +{ + xfs_bmap_free_item_t *xbf_first; /* list of to-be-free extents */ + int xbf_count; /* count of items on list */ + int xbf_low; /* kludge: alloc in low mode */ +} xfs_bmap_free_t; + +#define XFS_BMAP_MAX_NMAP 4 + +/* + * Flags for xfs_bmapi + */ +#define XFS_BMAPI_WRITE 0x001 /* write operation: allocate space */ +#define XFS_BMAPI_DELAY 0x002 /* delayed write operation */ +#define XFS_BMAPI_ENTIRE 0x004 /* return entire extent, not trimmed */ +#define XFS_BMAPI_METADATA 0x008 /* mapping metadata not user data */ +#define XFS_BMAPI_EXACT 0x010 /* allocate only to spec'd bounds */ +#define XFS_BMAPI_ATTRFORK 0x020 /* use attribute fork not data */ +#define XFS_BMAPI_ASYNC 0x040 /* bunmapi xactions can be async */ +#define XFS_BMAPI_RSVBLOCKS 0x080 /* OK to alloc. reserved data blocks */ +#define XFS_BMAPI_PREALLOC 0x100 /* preallocation op: unwritten space */ +#define XFS_BMAPI_IGSTATE 0x200 /* Ignore state - */ + /* combine contig. space */ +#define XFS_BMAPI_CONTIG 0x400 /* must allocate only one extent */ + +#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_BMAPI_AFLAG) +int xfs_bmapi_aflag(int w); +#define XFS_BMAPI_AFLAG(w) xfs_bmapi_aflag(w) +#else +#define XFS_BMAPI_AFLAG(w) ((w) == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0) +#endif + +/* + * Special values for xfs_bmbt_irec_t br_startblock field. + */ +#define DELAYSTARTBLOCK ((xfs_fsblock_t)-1LL) +#define HOLESTARTBLOCK ((xfs_fsblock_t)-2LL) + +#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_BMAP_INIT) +void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp); +#define XFS_BMAP_INIT(flp,fbp) xfs_bmap_init(flp,fbp) +#else +#define XFS_BMAP_INIT(flp,fbp) \ + ((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \ + (flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK) +#endif + +/* + * Argument structure for xfs_bmap_alloc. + */ +typedef struct xfs_bmalloca { + xfs_fsblock_t firstblock; /* i/o first block allocated */ + xfs_fsblock_t rval; /* starting block of new extent */ + xfs_fileoff_t off; /* offset in file filling in */ + struct xfs_trans *tp; /* transaction pointer */ + struct xfs_inode *ip; /* incore inode pointer */ + struct xfs_bmbt_irec *prevp; /* extent before the new one */ + struct xfs_bmbt_irec *gotp; /* extent after, or delayed */ + xfs_extlen_t alen; /* i/o length asked/allocated */ + xfs_extlen_t total; /* total blocks needed for xaction */ + xfs_extlen_t minlen; /* mininum allocation size (blocks) */ + xfs_extlen_t minleft; /* amount must be left after alloc */ + char eof; /* set if allocating past last extent */ + char wasdel; /* replacing a delayed allocation */ + char userdata;/* set if is user data */ + char low; /* low on space, using seq'l ags */ + char aeof; /* allocated space at eof */ +} xfs_bmalloca_t; + +#ifdef __KERNEL__ + +#if defined(XFS_BMAP_TRACE) +/* + * Trace operations for bmap extent tracing + */ +#define XFS_BMAP_KTRACE_DELETE 1 +#define XFS_BMAP_KTRACE_INSERT 2 +#define XFS_BMAP_KTRACE_PRE_UP 3 +#define XFS_BMAP_KTRACE_POST_UP 4 + +#define XFS_BMAP_TRACE_SIZE 4096 /* size of global trace buffer */ +#define XFS_BMAP_KTRACE_SIZE 32 /* size of per-inode trace buffer */ +extern ktrace_t *xfs_bmap_trace_buf; + +/* + * Add bmap trace insert entries for all the contents of the extent list. + */ +void +xfs_bmap_trace_exlist( + char *fname, /* function name */ + struct xfs_inode *ip, /* incore inode pointer */ + xfs_extnum_t cnt, /* count of entries in list */ + int whichfork); /* data or attr fork */ +#else +#define xfs_bmap_trace_exlist(f,ip,c,w) +#endif + +/* + * Convert inode from non-attributed to attributed. + * Must not be in a transaction, ip must not be locked. + */ +int /* error code */ +xfs_bmap_add_attrfork( + struct xfs_inode *ip, /* incore inode pointer */ + int rsvd); /* flag for reserved block allocation */ + +/* + * Add the extent to the list of extents to be free at transaction end. + * The list is maintained sorted (by block number). + */ +void +xfs_bmap_add_free( + xfs_fsblock_t bno, /* fs block number of extent */ + xfs_filblks_t len, /* length of extent */ + xfs_bmap_free_t *flist, /* list of extents */ + struct xfs_mount *mp); /* mount point structure */ + +/* + * Routine to clean up the free list data structure when + * an error occurs during a transaction. + */ +void +xfs_bmap_cancel( + xfs_bmap_free_t *flist); /* free list to clean up */ + +/* + * Compute and fill in the value of the maximum depth of a bmap btree + * in this filesystem. Done once, during mount. + */ +void +xfs_bmap_compute_maxlevels( + struct xfs_mount *mp, /* file system mount structure */ + int whichfork); /* data or attr fork */ + +/* + * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi + * caller. Frees all the extents that need freeing, which must be done + * last due to locking considerations. + * + * Return 1 if the given transaction was committed and a new one allocated, + * and 0 otherwise. + */ +int /* error */ +xfs_bmap_finish( + struct xfs_trans **tp, /* transaction pointer addr */ + xfs_bmap_free_t *flist, /* i/o: list extents to free */ + xfs_fsblock_t firstblock, /* controlled a.g. for allocs */ + int *committed); /* xact committed or not */ + +/* + * Returns the file-relative block number of the first unused block in the file. + * This is the lowest-address hole if the file has holes, else the first block + * past the end of file. + */ +int /* error */ +xfs_bmap_first_unused( + struct xfs_trans *tp, /* transaction pointer */ + struct xfs_inode *ip, /* incore inode */ + xfs_extlen_t len, /* size of hole to find */ + xfs_fileoff_t *unused, /* unused block num */ + int whichfork); /* data or attr fork */ + +/* + * Returns the file-relative block number of the last block + 1 before + * last_block (input value) in the file. + * This is not based on i_size, it is based on the extent list. + * Returns 0 for local files, as they do not have an extent list. + */ +int /* error */ +xfs_bmap_last_before( + struct xfs_trans *tp, /* transaction pointer */ + struct xfs_inode *ip, /* incore inode */ + xfs_fileoff_t *last_block, /* last block */ + int whichfork); /* data or attr fork */ + +/* + * Returns the file-relative block number of the first block past eof in + * the file. This is not based on i_size, it is based on the extent list. + * Returns 0 for local files, as they do not have an extent list. + */ +int /* error */ +xfs_bmap_last_offset( + struct xfs_trans *tp, /* transaction pointer */ + struct xfs_inode *ip, /* incore inode */ + xfs_fileoff_t *unused, /* last block num */ + int whichfork); /* data or attr fork */ + +/* + * Returns whether the selected fork of the inode has exactly one + * block or not. For the data fork we check this matches di_size, + * implying the file's range is 0..bsize-1. + */ +int +xfs_bmap_one_block( + struct xfs_inode *ip, /* incore inode */ + int whichfork); /* data or attr fork */ + +/* + * Read in the extents to iu_extents. + * All inode fields are set up by caller, we just traverse the btree + * and copy the records in. + */ +int /* error */ +xfs_bmap_read_extents( + struct xfs_trans *tp, /* transaction pointer */ + struct xfs_inode *ip, /* incore inode */ + int whichfork); /* data or attr fork */ + +/* + * Map file blocks to filesystem blocks. + * File range is given by the bno/len pair. + * Adds blocks to file if a write ("flags & XFS_BMAPI_WRITE" set) + * into a hole or past eof. + * Only allocates blocks from a single allocation group, + * to avoid locking problems. + * The returned value in "firstblock" from the first call in a transaction + * must be remembered and presented to subsequent calls in "firstblock". + * An upper bound for the number of blocks to be allocated is supplied to + * the first call in "total"; if no allocation group has that many free + * blocks then the call will fail (return NULLFSBLOCK in "firstblock"). + */ +int /* error */ +xfs_bmapi( + struct xfs_trans *tp, /* transaction pointer */ + struct xfs_inode *ip, /* incore inode */ + xfs_fileoff_t bno, /* starting file offs. mapped */ + xfs_filblks_t len, /* length to map in file */ + int flags, /* XFS_BMAPI_... */ + xfs_fsblock_t *firstblock, /* first allocated block + controls a.g. for allocs */ + xfs_extlen_t total, /* total blocks needed */ + struct xfs_bmbt_irec *mval, /* output: map values */ + int *nmap, /* i/o: mval size/count */ + xfs_bmap_free_t *flist); /* i/o: list extents to free */ + +/* + * Map file blocks to filesystem blocks, simple version. + * One block only, read-only. + * For flags, only the XFS_BMAPI_ATTRFORK flag is examined. + * For the other flag values, the effect is as if XFS_BMAPI_METADATA + * was set and all the others were clear. + */ +int /* error */ +xfs_bmapi_single( + struct xfs_trans *tp, /* transaction pointer */ + struct xfs_inode *ip, /* incore inode */ + int whichfork, /* data or attr fork */ + xfs_fsblock_t *fsb, /* output: mapped block */ + xfs_fileoff_t bno); /* starting file offs. mapped */ + +/* + * Unmap (remove) blocks from a file. + * If nexts is nonzero then the number of extents to remove is limited to + * that value. If not all extents in the block range can be removed then + * *done is set. + */ +int /* error */ +xfs_bunmapi( + struct xfs_trans *tp, /* transaction pointer */ + struct xfs_inode *ip, /* incore inode */ + xfs_fileoff_t bno, /* starting offset to unmap */ + xfs_filblks_t len, /* length to unmap in file */ + int flags, /* XFS_BMAPI_... */ + xfs_extnum_t nexts, /* number of extents max */ + xfs_fsblock_t *firstblock, /* first allocated block + controls a.g. for allocs */ + xfs_bmap_free_t *flist, /* i/o: list extents to free */ + int *done); /* set if not done yet */ + +/* + * Fcntl interface to xfs_bmapi. + */ +int /* error code */ +xfs_getbmap( + bhv_desc_t *bdp, /* XFS behavior descriptor*/ + struct getbmap *bmv, /* user bmap structure */ + void __user *ap, /* pointer to user's array */ + int iflags); /* interface flags */ + +/* + * Check the last inode extent to determine whether this allocation will result + * in blocks being allocated at the end of the file. When we allocate new data + * blocks at the end of the file which do not start at the previous data block, + * we will try to align the new blocks at stripe unit boundaries. + */ +int +xfs_bmap_isaeof( + struct xfs_inode *ip, + xfs_fileoff_t off, + int whichfork, + char *aeof); + +/* + * Check if the endoff is outside the last extent. If so the caller will grow + * the allocation to a stripe unit boundary + */ +int +xfs_bmap_eof( + struct xfs_inode *ip, + xfs_fileoff_t endoff, + int whichfork, + int *eof); + +/* + * Count fsblocks of the given fork. + */ +int +xfs_bmap_count_blocks( + xfs_trans_t *tp, + struct xfs_inode *ip, + int whichfork, + int *count); + +/* + * Check an extent list, which has just been read, for + * any bit in the extent flag field. + */ +int +xfs_check_nostate_extents( + xfs_bmbt_rec_t *ep, + xfs_extnum_t num); + +#endif /* __KERNEL__ */ + +#endif /* __XFS_BMAP_H__ */ |