/*

   * 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_RTALLOC_H__
  #define	__XFS_RTALLOC_H__
  
  struct xfs_mount;
  struct xfs_trans;

  /* Min and max rt extent sizes, specified in bytes */
  #define	XFS_MAX_RTEXTSIZE	(1024 * 1024 * 1024)	/* 1GB */

  #define	XFS_DFL_RTEXTSIZE	(64 * 1024)	        /* 64kB */
  #define	XFS_MIN_RTEXTSIZE	(4 * 1024)		/* 4kB */

  
  /*
   * Constants for bit manipulations.
   */
  #define	XFS_NBBYLOG	3		/* log2(NBBY) */
  #define	XFS_WORDLOG	2		/* log2(sizeof(xfs_rtword_t)) */
  #define	XFS_NBWORDLOG	(XFS_NBBYLOG + XFS_WORDLOG)
  #define	XFS_NBWORD	(1 << XFS_NBWORDLOG)
  #define	XFS_WORDMASK	((1 << XFS_WORDLOG) - 1)
  
  #define	XFS_BLOCKSIZE(mp)	((mp)->m_sb.sb_blocksize)
  #define	XFS_BLOCKMASK(mp)	((mp)->m_blockmask)
  #define	XFS_BLOCKWSIZE(mp)	((mp)->m_blockwsize)
  #define	XFS_BLOCKWMASK(mp)	((mp)->m_blockwmask)
  
  /*
   * Summary and bit manipulation macros.
   */
  #define	XFS_SUMOFFS(mp,ls,bb)	((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
  #define	XFS_SUMOFFSTOBLOCK(mp,s)	\
  	(((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
  #define	XFS_SUMPTR(mp,bp,so)	\

  	((xfs_suminfo_t *)((bp)->b_addr + \

  		(((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
  
  #define	XFS_BITTOBLOCK(mp,bi)	((bi) >> (mp)->m_blkbit_log)
  #define	XFS_BLOCKTOBIT(mp,bb)	((bb) << (mp)->m_blkbit_log)
  #define	XFS_BITTOWORD(mp,bi)	\
  	((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
  
  #define	XFS_RTMIN(a,b)	((a) < (b) ? (a) : (b))
  #define	XFS_RTMAX(a,b)	((a) > (b) ? (a) : (b))
  
  #define	XFS_RTLOBIT(w)	xfs_lowbit32(w)
  #define	XFS_RTHIBIT(w)	xfs_highbit32(w)
  
  #if XFS_BIG_BLKNOS
  #define	XFS_RTBLOCKLOG(b)	xfs_highbit64(b)
  #else
  #define	XFS_RTBLOCKLOG(b)	xfs_highbit32(b)
  #endif
  
  
  #ifdef __KERNEL__
  
  #ifdef CONFIG_XFS_RT
  /*
   * Function prototypes for exported functions.
   */
  
  /*
   * Allocate an extent in the realtime subvolume, with the usual allocation
   * parameters.  The length units are all in realtime extents, as is the
   * result block number.
   */
  int					/* error */
  xfs_rtallocate_extent(
  	struct xfs_trans	*tp,	/* transaction pointer */
  	xfs_rtblock_t		bno,	/* starting block number to allocate */
  	xfs_extlen_t		minlen,	/* minimum length to allocate */
  	xfs_extlen_t		maxlen,	/* maximum length to allocate */
  	xfs_extlen_t		*len,	/* out: actual length allocated */
  	xfs_alloctype_t		type,	/* allocation type XFS_ALLOCTYPE... */
  	int			wasdel,	/* was a delayed allocation extent */
  	xfs_extlen_t		prod,	/* extent product factor */
  	xfs_rtblock_t		*rtblock); /* out: start block allocated */
  
  /*
   * Free an extent in the realtime subvolume.  Length is expressed in
   * realtime extents, as is the block number.
   */
  int					/* error */
  xfs_rtfree_extent(
  	struct xfs_trans	*tp,	/* transaction pointer */
  	xfs_rtblock_t		bno,	/* starting block number to free */
  	xfs_extlen_t		len);	/* length of extent freed */
  
  /*
   * Initialize realtime fields in the mount structure.
   */
  int					/* error */
  xfs_rtmount_init(
  	struct xfs_mount	*mp);	/* file system mount structure */

  void
  xfs_rtunmount_inodes(
  	struct xfs_mount	*mp);

  
  /*
   * Get the bitmap and summary inodes into the mount structure
   * at mount time.
   */
  int					/* error */
  xfs_rtmount_inodes(
  	struct xfs_mount	*mp);	/* file system mount structure */
  
  /*
   * Pick an extent for allocation at the start of a new realtime file.
   * Use the sequence number stored in the atime field of the bitmap inode.
   * Translate this to a fraction of the rtextents, and return the product
   * of rtextents and the fraction.
   * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
   */
  int					/* error */
  xfs_rtpick_extent(
  	struct xfs_mount	*mp,	/* file system mount point */
  	struct xfs_trans	*tp,	/* transaction pointer */
  	xfs_extlen_t		len,	/* allocation length (rtextents) */
  	xfs_rtblock_t		*pick);	/* result rt extent */
  
  /*

   * Grow the realtime area of the filesystem.
   */
  int
  xfs_growfs_rt(
  	struct xfs_mount	*mp,	/* file system mount structure */
  	xfs_growfs_rt_t		*in);	/* user supplied growfs struct */
  
  #else
  # define xfs_rtallocate_extent(t,b,min,max,l,a,f,p,rb)  (ENOSYS)
  # define xfs_rtfree_extent(t,b,l)                       (ENOSYS)
  # define xfs_rtpick_extent(m,t,l,rb)                    (ENOSYS)
  # define xfs_growfs_rt(mp,in)                           (ENOSYS)

  static inline int		/* error */
  xfs_rtmount_init(
  	xfs_mount_t	*mp)	/* file system mount structure */
  {
  	if (mp->m_sb.sb_rblocks == 0)
  		return 0;

  	xfs_warn(mp, "Not built with CONFIG_XFS_RT");

  	return ENOSYS;
  }

  # define xfs_rtmount_inodes(m)  (((mp)->m_sb.sb_rblocks == 0)? 0 : (ENOSYS))

  # define xfs_rtunmount_inodes(m)

  #endif	/* CONFIG_XFS_RT */
  
  #endif	/* __KERNEL__ */
  
  #endif	/* __XFS_RTALLOC_H__ */