/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms 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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_BMAP_H__
#define __XFS_BMAP_H__
struct getbmap;
struct xfs_bmbt_irec;
struct xfs_ifork;
struct xfs_inode;
struct xfs_mount;
struct xfs_trans;
extern kmem_zone_t *xfs_bmap_free_item_zone;
/*
* DELTA: describe a change to the in-core extent list.
*
* Internally the use of xed_blockount is somewhat funky.
* xed_blockcount contains an offset much of the time because this
* makes merging changes easier. (xfs_fileoff_t and xfs_filblks_t are
* the same underlying type).
*/
typedef struct xfs_extdelta
{
xfs_fileoff_t xed_startoff; /* offset of range */
xfs_filblks_t xed_blockcount; /* blocks in range */
} xfs_extdelta_t;
/*
* 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.
*
* xbf_low is used by the allocator to activate the lowspace algorithm -
* when free space is running low the extent allocator may choose to
* allocate an extent from an AG without leaving sufficient space for
* a btree split when inserting the new extent. In this case the allocator
* will enable the lowspace algorithm which is supposed to allow further
* allocations (such as btree splits and newroots) to allocate from
* sequential AGs. In order to avoid locking AGs out of order the lowspace
* algorithm will start searching for free space from AG 0. If the correct
* transaction reservations have been made then this algorithm will eventually
* find all the space it needs.
*/
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; /* 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 */
/* XFS_BMAPI_DIRECT_IO 0x800 */
#define XFS_BMAPI_CONVERT 0x1000 /* unwritten extent conversion - */
/* need write cache flushing and no */
/* additional allocation alignments */
static inline int xfs_bmapi_aflag(int w)
{
return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
}
/*
* Special values for xfs_bmbt_irec_t br_startblock field.
*/
#define DELAYSTARTBLOCK ((xfs_fsblock_t)-1LL)
#define HOLESTARTBLOCK ((xfs_fsblock_t)-2LL)
static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
{
((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
(flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
}
/*
* 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; /* minimum 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 */
char conv; /* overwriting unwritten extents */
} xfs_bmalloca_t;
#if defined(__KERNEL__) && 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(
const 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 */
#define XFS_BMAP_TRACE_EXLIST(ip,c,w) \
xfs_bmap_trace_exlist(__func__,ip,c,w)
#else /* __KERNEL__ && XFS_BMAP_TRACE */
#define XFS_BMAP_TRACE_EXLIST(ip,c,w)
#endif /* __KERNEL__ && XFS_BMAP_TRACE */
/*
* 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 size, /* space needed for new attribute */
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 */
/*
* 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 */
xfs_extdelta_t *delta); /* o: change made to incore
extents */
/*
* 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 */
xfs_extdelta_t *delta, /* o: change made to incore
extents */
int *done); /* set if not done yet */
/*
* Check an extent list, which has just been read, for
* any bit in the extent flag field.
*/
int
xfs_check_nostate_extents(
struct xfs_ifork *ifp,
xfs_extnum_t idx,
xfs_extnum_t num);
uint
xfs_default_attroffset(
struct xfs_inode *ip);
#ifdef __KERNEL__
/*
* 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 */
int *committed); /* xact committed or not */
/* bmap to userspace formatter - copy to user & advance pointer */
typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *, int *);
/*
* Get inode's extents as described in bmv, and format for output.
*/
int /* error code */
xfs_getbmap(
xfs_inode_t *ip,
struct getbmapx *bmv, /* user bmap structure */
xfs_bmap_format_t formatter, /* format to user */
void *arg); /* formatter arg */
/*
* 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);
#endif /* __KERNEL__ */
#endif /* __XFS_BMAP_H__ */
