xfs_inode.h

linux 内核源代码

/*
 * 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_H__
#define	__XFS_INODE_H__

struct xfs_dinode;
struct xfs_dinode_core;


/*
 * Fork identifiers.
 */
#define	XFS_DATA_FORK	0
#define	XFS_ATTR_FORK	1

/*
 * 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 */
	xfs_bmbt_block_t	*if_broot;	/* file's incore btree root */
	short			if_broot_bytes;	/* bytes allocated for root */
	unsigned char		if_flags;	/* per-fork flags */
	unsigned char		if_ext_max;	/* max # of extent records */
	xfs_extnum_t		if_lastex;	/* last if_extents used */
	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;

/*
 * Flags for xfs_ichgtime().
 */
#define	XFS_ICHGTIME_MOD	0x1	/* data fork modification timestamp */
#define	XFS_ICHGTIME_ACC	0x2	/* data fork access timestamp */
#define	XFS_ICHGTIME_CHG	0x4	/* inode field change timestamp */

/*
 * 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 */

/*
 * Flags for xfs_itobp(), xfs_imap() and xfs_dilocate().
 */
#define XFS_IMAP_LOOKUP		0x1
#define XFS_IMAP_BULKSTAT	0x2

#ifdef __KERNEL__
struct bhv_desc;
struct cred;
struct ktrace;
struct xfs_buf;
struct xfs_bmap_free;
struct xfs_bmbt_irec;
struct xfs_bmbt_block;
struct xfs_inode;
struct xfs_inode_log_item;
struct xfs_mount;
struct xfs_trans;
struct xfs_dquot;

#if defined(XFS_ILOCK_TRACE)
#define XFS_ILOCK_KTRACE_SIZE	32
extern ktrace_t *xfs_ilock_trace_buf;
extern void xfs_ilock_trace(struct xfs_inode *, int, unsigned int, inst_t *);
#else
#define	xfs_ilock_trace(i,n,f,ra)
#endif

typedef struct dm_attrs_s {
	__uint32_t	da_dmevmask;	/* DMIG event mask */
	__uint16_t	da_dmstate;	/* DMIG state info */
	__uint16_t	da_pad;		/* DMIG extra padding */
} dm_attrs_t;

typedef struct xfs_iocore {
	void			*io_obj;	/* pointer to container
						 * inode or dcxvn structure */
	struct xfs_mount	*io_mount;	/* fs mount struct ptr */
#ifdef DEBUG
	mrlock_t		*io_lock;	/* inode IO lock */
	mrlock_t		*io_iolock;	/* inode IO lock */
#endif

	/* I/O state */
	xfs_fsize_t		io_new_size;	/* sz when write completes */

	/* Miscellaneous state. */
	unsigned int		io_flags;	/* IO related flags */

	/* DMAPI state */
	dm_attrs_t		io_dmattrs;

} xfs_iocore_t;

#define        io_dmevmask     io_dmattrs.da_dmevmask
#define        io_dmstate      io_dmattrs.da_dmstate

#define XFS_IO_INODE(io)	((xfs_inode_t *) ((io)->io_obj))
#define XFS_IO_DCXVN(io)	((dcxvn_t *) ((io)->io_obj))

/*
 * Flags in the flags field
 */

#define XFS_IOCORE_RT		0x1

/*
 * xfs_iocore prototypes
 */

extern void xfs_iocore_inode_init(struct xfs_inode *);
extern void xfs_iocore_inode_reinit(struct xfs_inode *);

/*
 * This is the xfs inode cluster structure.  This structure is used by
 * xfs_iflush to find inodes that share a cluster and can be flushed to disk at
 * the same time.
 */
typedef struct xfs_icluster {
	struct hlist_head	icl_inodes;	/* list of inodes on cluster */
	xfs_daddr_t		icl_blkno;	/* starting block number of
						 * the cluster */
	struct xfs_buf		*icl_buf;	/* the inode buffer */
	lock_t			icl_lock;	/* inode list lock */
} xfs_icluster_t;

/*
 * This is the xfs in-core inode structure.
 * Most of the on-disk inode is embedded in the i_d field.
 *
 * The extent pointers/inline file space, however, are managed
 * separately.  The memory for this information is pointed to by
 * the if_u1 unions depending on the type of the data.
 * This is used to linearize the array of extents for fast in-core
 * access.  This is used until the file's number of extents
 * surpasses XFS_MAX_INCORE_EXTENTS, at which point all extent pointers
 * are accessed through the buffer cache.
 *
 * Other state kept in the in-core inode is used for identification,
 * locking, transactional updating, etc of the inode.
 *
 * Generally, we do not want to hold the i_rlock while holding the
 * i_ilock. Hierarchy is i_iolock followed by i_rlock.
 *
 * xfs_iptr_t contains all the inode fields upto and including the
 * i_mnext and i_mprev fields, it is used as a marker in the inode
 * chain off the mount structure by xfs_sync calls.
 */

typedef struct xfs_ictimestamp {
	__int32_t	t_sec;		/* timestamp seconds */
	__int32_t	t_nsec;		/* timestamp nanoseconds */
} xfs_ictimestamp_t;

/*
 * NOTE:  This structure must be kept identical to struct xfs_dinode_core
 * 	  in xfs_dinode.h except for the endianess annotations.
 */
typedef struct xfs_icdinode {
	__uint16_t	di_magic;	/* inode magic # = XFS_DINODE_MAGIC */
	__uint16_t	di_mode;	/* mode and type of file */
	__int8_t	di_version;	/* inode version */
	__int8_t	di_format;	/* format of di_c data */
	__uint16_t	di_onlink;	/* old number of links to file */
	__uint32_t	di_uid;		/* owner's user id */
	__uint32_t	di_gid;		/* owner's group id */
	__uint32_t	di_nlink;	/* number of links to file */
	__uint16_t	di_projid;	/* owner's project id */
	__uint8_t	di_pad[8];	/* unused, zeroed space */
	__uint16_t	di_flushiter;	/* incremented on flush */
	xfs_ictimestamp_t di_atime;	/* time last accessed */
	xfs_ictimestamp_t di_mtime;	/* time last modified */
	xfs_ictimestamp_t di_ctime;	/* time created/inode modified */
	xfs_fsize_t	di_size;	/* number of bytes in file */
	xfs_drfsbno_t	di_nblocks;	/* # of direct & btree blocks used */
	xfs_extlen_t	di_extsize;	/* basic/minimum extent size for file */
	xfs_extnum_t	di_nextents;	/* number of extents in data fork */
	xfs_aextnum_t	di_anextents;	/* number of extents in attribute fork*/
	__uint8_t	di_forkoff;	/* attr fork offs, <<3 for 64b align */
	__int8_t	di_aformat;	/* format of attr fork's data */
	__uint32_t	di_dmevmask;	/* DMIG event mask */
	__uint16_t	di_dmstate;	/* DMIG state info */
	__uint16_t	di_flags;	/* random flags, XFS_DIFLAG_... */
	__uint32_t	di_gen;		/* generation number */
} xfs_icdinode_t;

typedef struct {
	struct xfs_inode	*ip_mnext;	/* next inode in mount list */
	struct xfs_inode	*ip_mprev;	/* ptr to prev inode */
	struct xfs_mount	*ip_mount;	/* fs mount struct ptr */
} xfs_iptr_t;

typedef struct xfs_inode {
	/* Inode linking and identification information. */
	struct xfs_inode	*i_mnext;	/* next inode in mount list */
	struct xfs_inode	*i_mprev;	/* ptr to prev inode */
	struct xfs_mount	*i_mount;	/* fs mount struct ptr */
	struct list_head	i_reclaim;	/* reclaim list */
	bhv_vnode_t		*i_vnode;	/* vnode backpointer */
	struct xfs_dquot	*i_udquot;	/* user dquot */
	struct xfs_dquot	*i_gdquot;	/* group dquot */

	/* Inode location stuff */
	xfs_ino_t		i_ino;		/* inode number (agno/agino)*/
	xfs_daddr_t		i_blkno;	/* blkno of inode buffer */
	ushort			i_len;		/* len of inode buffer */
	ushort			i_boffset;	/* off of inode in buffer */

	/* Extent information. */
	xfs_ifork_t		*i_afp;		/* attribute fork pointer */
	xfs_ifork_t		i_df;		/* data fork */

	/* Transaction and locking information. */
	struct xfs_trans	*i_transp;	/* ptr to owning transaction*/
	struct xfs_inode_log_item *i_itemp;	/* logging information */
	mrlock_t		i_lock;		/* inode lock */
	mrlock_t		i_iolock;	/* inode IO lock */
	sema_t			i_flock;	/* inode flush lock */
	atomic_t		i_pincount;	/* inode pin count */
	wait_queue_head_t	i_ipin_wait;	/* inode pinning wait queue */
	spinlock_t		i_flags_lock;	/* inode i_flags lock */
#ifdef HAVE_REFCACHE
	struct xfs_inode	**i_refcache;	/* ptr to entry in ref cache */
	struct xfs_inode	*i_release;	/* inode to unref */
#endif
	/* I/O state */
	xfs_iocore_t		i_iocore;	/* I/O core */

	/* Miscellaneous state. */
	unsigned short		i_flags;	/* see defined flags below */
	unsigned char		i_update_core;	/* timestamps/size is dirty */
	unsigned char		i_update_size;	/* di_size field is dirty */
	unsigned int		i_gen;		/* generation count */
	unsigned int		i_delayed_blks;	/* count of delay alloc blks */

	xfs_icdinode_t		i_d;		/* most of ondisk inode */
	xfs_icluster_t		*i_cluster;	/* cluster list header */
	struct hlist_node	i_cnode;	/* cluster link node */

	xfs_fsize_t		i_size;		/* in-memory size */
	atomic_t		i_iocount;	/* outstanding I/O count */
	/* Trace buffers per inode. */
#ifdef XFS_VNODE_TRACE
	struct ktrace		*i_trace;	/* general inode trace */
#endif
#ifdef XFS_BMAP_TRACE
	struct ktrace		*i_xtrace;	/* inode extent list trace */
#endif
#ifdef XFS_BMBT_TRACE
	struct ktrace		*i_btrace;	/* inode bmap btree trace */
#endif
#ifdef XFS_RW_TRACE
	struct ktrace		*i_rwtrace;	/* inode read/write trace */