xfs_aops.h

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/*
 * Copyright (c) 2005-2006 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_AOPS_H__
#define __XFS_AOPS_H__

extern mempool_t *xfs_ioend_pool;

/*
 * Types of I/O for bmap clustering and I/O completion tracking.
 */
enum {
    XFS_IO_DIRECT = 0,  /* special case for direct I/O ioends */
    XFS_IO_DELALLOC,    /* covers delalloc region */
    XFS_IO_UNWRITTEN,   /* covers allocated but uninitialized data */
    XFS_IO_OVERWRITE,   /* covers already allocated extent */
};

#define XFS_IO_TYPES \
    { 0,            "" }, \
    { XFS_IO_DELALLOC,      "delalloc" }, \
    { XFS_IO_UNWRITTEN,     "unwritten" }, \
    { XFS_IO_OVERWRITE,     "overwrite" }

/*
 * xfs_ioend struct manages large extent writes for XFS.
 * It can manage several multi-page bio's at once.
 */
typedef struct xfs_ioend {
    struct xfs_ioend    *io_list;   /* next ioend in chain */
    unsigned int        io_type;    /* delalloc / unwritten */
    int         io_error;   /* I/O error code */
    atomic_t        io_remaining;   /* hold count */
    unsigned int        io_isasync : 1; /* needs aio_complete */
    unsigned int        io_isdirect : 1;/* direct I/O */
    struct inode        *io_inode;  /* file being written to */
    struct buffer_head  *io_buffer_head;/* buffer linked list head */
    struct buffer_head  *io_buffer_tail;/* buffer linked list tail */
    size_t          io_size;    /* size of the extent */
    xfs_off_t       io_offset;  /* offset in the file */
    struct work_struct  io_work;    /* xfsdatad work queue */
    struct xfs_trans    *io_append_trans;/* xact. for size update */
    struct kiocb        *io_iocb;
    int         io_result;
} xfs_ioend_t;

extern const struct address_space_operations xfs_address_space_operations;
extern int xfs_get_blocks(struct inode *, sector_t, struct buffer_head *, int);

extern void xfs_count_page_state(struct page *, int *, int *);

#endif /* __XFS_AOPS_H__ */