linux/fs/xfs/xfs_inode_fork.h

173 lines
6.6 KiB
C

/*
* Copyright (c) 2000-2003,2005 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_INODE_FORK_H__
#define __XFS_INODE_FORK_H__
struct xfs_inode_log_item;
struct xfs_dinode;
/*
* The following xfs_ext_irec_t struct introduces a second (top) level
* to the in-core extent allocation scheme. These structs are allocated
* in a contiguous block, creating an indirection array where each entry
* (irec) contains a pointer to a buffer of in-core extent records which
* it manages. Each extent buffer is 4k in size, since 4k is the system
* page size on Linux i386 and systems with larger page sizes don't seem
* to gain much, if anything, by using their native page size as the
* extent buffer size. Also, using 4k extent buffers everywhere provides
* a consistent interface for CXFS across different platforms.
*
* There is currently no limit on the number of irec's (extent lists)
* allowed, so heavily fragmented files may require an indirection array
* which spans multiple system pages of memory. The number of extents
* which would require this amount of contiguous memory is very large
* and should not cause problems in the foreseeable future. However,
* if the memory needed for the contiguous array ever becomes a problem,
* it is possible that a third level of indirection may be required.
*/
typedef struct xfs_ext_irec {
xfs_bmbt_rec_host_t *er_extbuf; /* block of extent records */
xfs_extnum_t er_extoff; /* extent offset in file */
xfs_extnum_t er_extcount; /* number of extents in page/block */
} xfs_ext_irec_t;
/*
* File incore extent information, present for each of data & attr forks.
*/
#define XFS_IEXT_BUFSZ 4096
#define XFS_LINEAR_EXTS (XFS_IEXT_BUFSZ / (uint)sizeof(xfs_bmbt_rec_t))
#define XFS_INLINE_EXTS 2
#define XFS_INLINE_DATA 32
typedef struct xfs_ifork {
int if_bytes; /* bytes in if_u1 */
int if_real_bytes; /* bytes allocated in if_u1 */
struct xfs_btree_block *if_broot; /* file's incore btree root */
short if_broot_bytes; /* bytes allocated for root */
unsigned char if_flags; /* per-fork flags */
union {
xfs_bmbt_rec_host_t *if_extents;/* linear map file exts */
xfs_ext_irec_t *if_ext_irec; /* irec map file exts */
char *if_data; /* inline file data */
} if_u1;
union {
xfs_bmbt_rec_host_t if_inline_ext[XFS_INLINE_EXTS];
/* very small file extents */
char if_inline_data[XFS_INLINE_DATA];
/* very small file data */
xfs_dev_t if_rdev; /* dev number if special */
uuid_t if_uuid; /* mount point value */
} if_u2;
} xfs_ifork_t;
/*
* Per-fork incore inode flags.
*/
#define XFS_IFINLINE 0x01 /* Inline data is read in */
#define XFS_IFEXTENTS 0x02 /* All extent pointers are read in */
#define XFS_IFBROOT 0x04 /* i_broot points to the bmap b-tree root */
#define XFS_IFEXTIREC 0x08 /* Indirection array of extent blocks */
/*
* Fork handling.
*/
#define XFS_IFORK_Q(ip) ((ip)->i_d.di_forkoff != 0)
#define XFS_IFORK_BOFF(ip) ((int)((ip)->i_d.di_forkoff << 3))
#define XFS_IFORK_PTR(ip,w) \
((w) == XFS_DATA_FORK ? \
&(ip)->i_df : \
(ip)->i_afp)
#define XFS_IFORK_DSIZE(ip) \
(XFS_IFORK_Q(ip) ? \
XFS_IFORK_BOFF(ip) : \
XFS_LITINO((ip)->i_mount, (ip)->i_d.di_version))
#define XFS_IFORK_ASIZE(ip) \
(XFS_IFORK_Q(ip) ? \
XFS_LITINO((ip)->i_mount, (ip)->i_d.di_version) - \
XFS_IFORK_BOFF(ip) : \
0)
#define XFS_IFORK_SIZE(ip,w) \
((w) == XFS_DATA_FORK ? \
XFS_IFORK_DSIZE(ip) : \
XFS_IFORK_ASIZE(ip))
#define XFS_IFORK_FORMAT(ip,w) \
((w) == XFS_DATA_FORK ? \
(ip)->i_d.di_format : \
(ip)->i_d.di_aformat)
#define XFS_IFORK_FMT_SET(ip,w,n) \
((w) == XFS_DATA_FORK ? \
((ip)->i_d.di_format = (n)) : \
((ip)->i_d.di_aformat = (n)))
#define XFS_IFORK_NEXTENTS(ip,w) \
((w) == XFS_DATA_FORK ? \
(ip)->i_d.di_nextents : \
(ip)->i_d.di_anextents)
#define XFS_IFORK_NEXT_SET(ip,w,n) \
((w) == XFS_DATA_FORK ? \
((ip)->i_d.di_nextents = (n)) : \
((ip)->i_d.di_anextents = (n)))
#define XFS_IFORK_MAXEXT(ip, w) \
(XFS_IFORK_SIZE(ip, w) / sizeof(xfs_bmbt_rec_t))
int xfs_iformat_fork(struct xfs_inode *, struct xfs_dinode *);
void xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
struct xfs_inode_log_item *, int,
struct xfs_buf *);
void xfs_idestroy_fork(struct xfs_inode *, int);
void xfs_idata_realloc(struct xfs_inode *, int, int);
void xfs_iroot_realloc(struct xfs_inode *, int, int);
int xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int);
int xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *,
int);
struct xfs_bmbt_rec_host *
xfs_iext_get_ext(struct xfs_ifork *, xfs_extnum_t);
void xfs_iext_insert(struct xfs_inode *, xfs_extnum_t, xfs_extnum_t,
struct xfs_bmbt_irec *, int);
void xfs_iext_add(struct xfs_ifork *, xfs_extnum_t, int);
void xfs_iext_add_indirect_multi(struct xfs_ifork *, int,
xfs_extnum_t, int);
void xfs_iext_remove(struct xfs_inode *, xfs_extnum_t, int, int);
void xfs_iext_remove_inline(struct xfs_ifork *, xfs_extnum_t, int);
void xfs_iext_remove_direct(struct xfs_ifork *, xfs_extnum_t, int);
void xfs_iext_remove_indirect(struct xfs_ifork *, xfs_extnum_t, int);
void xfs_iext_realloc_direct(struct xfs_ifork *, int);
void xfs_iext_direct_to_inline(struct xfs_ifork *, xfs_extnum_t);
void xfs_iext_inline_to_direct(struct xfs_ifork *, int);
void xfs_iext_destroy(struct xfs_ifork *);
struct xfs_bmbt_rec_host *
xfs_iext_bno_to_ext(struct xfs_ifork *, xfs_fileoff_t, int *);
struct xfs_ext_irec *
xfs_iext_bno_to_irec(struct xfs_ifork *, xfs_fileoff_t, int *);
struct xfs_ext_irec *
xfs_iext_idx_to_irec(struct xfs_ifork *, xfs_extnum_t *, int *,
int);
void xfs_iext_irec_init(struct xfs_ifork *);
struct xfs_ext_irec *
xfs_iext_irec_new(struct xfs_ifork *, int);
void xfs_iext_irec_remove(struct xfs_ifork *, int);
void xfs_iext_irec_compact(struct xfs_ifork *);
void xfs_iext_irec_compact_pages(struct xfs_ifork *);
void xfs_iext_irec_compact_full(struct xfs_ifork *);
void xfs_iext_irec_update_extoffs(struct xfs_ifork *, int, int);
extern struct kmem_zone *xfs_ifork_zone;
#endif /* __XFS_INODE_FORK_H__ */