[deliverable/linux.git] / fs / ocfs2 / suballoc.h

/* -*- mode: c; c-basic-offset: 8; -*-
 * vim: noexpandtab sw=8 ts=8 sts=0:
 *
 * suballoc.h
 *
 * Defines sub allocator api
 *
 * Copyright (C) 2003, 2004 Oracle.  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; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will 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 to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#ifndef _CHAINALLOC_H_
#define _CHAINALLOC_H_

typedef int (group_search_t)(struct inode *,
			     struct buffer_head *,
			     u32,
			     u32,
			     u16 *,
			     u16 *);

struct ocfs2_alloc_context {
	struct inode *ac_inode;    /* which bitmap are we allocating from? */
	struct buffer_head *ac_bh; /* file entry bh */
	u32    ac_alloc_slot;   /* which slot are we allocating from? */
	u32    ac_bits_wanted;
	u32    ac_bits_given;
#define OCFS2_AC_USE_LOCAL 1
#define OCFS2_AC_USE_MAIN  2
#define OCFS2_AC_USE_INODE 3
#define OCFS2_AC_USE_META  4
	u32    ac_which;

	/* these are used by the chain search */
	u16    ac_chain;
	int    ac_allow_chain_relink;
	group_search_t *ac_group_search;

	u64    ac_last_group;
};

void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
static inline int ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context *ac)
{
	return ac->ac_bits_wanted - ac->ac_bits_given;
}

/*
 * Please note that the caller must make sure that root_el is the root
 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
 * the result may be wrong.
 */
int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
			       struct ocfs2_extent_list *root_el,
			       struct ocfs2_alloc_context **ac);
int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
			    struct ocfs2_alloc_context **ac);
int ocfs2_reserve_clusters(struct ocfs2_super *osb,
			   u32 bits_wanted,
			   struct ocfs2_alloc_context **ac);

int ocfs2_claim_metadata(struct ocfs2_super *osb,
			 handle_t *handle,
			 struct ocfs2_alloc_context *ac,
			 u32 bits_wanted,
			 u16 *suballoc_bit_start,
			 u32 *num_bits,
			 u64 *blkno_start);
int ocfs2_claim_new_inode(struct ocfs2_super *osb,
			  handle_t *handle,
			  struct ocfs2_alloc_context *ac,
			  u16 *suballoc_bit,
			  u64 *fe_blkno);
int ocfs2_claim_clusters(struct ocfs2_super *osb,
			 handle_t *handle,
			 struct ocfs2_alloc_context *ac,
			 u32 min_clusters,
			 u32 *cluster_start,
			 u32 *num_clusters);
/*
 * Use this variant of ocfs2_claim_clusters to specify a maxiumum
 * number of clusters smaller than the allocation reserved.
 */
int __ocfs2_claim_clusters(struct ocfs2_super *osb,
			   handle_t *handle,
			   struct ocfs2_alloc_context *ac,
			   u32 min_clusters,
			   u32 max_clusters,
			   u32 *cluster_start,
			   u32 *num_clusters);

int ocfs2_free_suballoc_bits(handle_t *handle,
			     struct inode *alloc_inode,
			     struct buffer_head *alloc_bh,
			     unsigned int start_bit,
			     u64 bg_blkno,
			     unsigned int count);
int ocfs2_free_dinode(handle_t *handle,
		      struct inode *inode_alloc_inode,
		      struct buffer_head *inode_alloc_bh,
		      struct ocfs2_dinode *di);
int ocfs2_free_clusters(handle_t *handle,
			struct inode *bitmap_inode,
			struct buffer_head *bitmap_bh,
			u64 start_blk,
			unsigned int num_clusters);

static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
{
	u64 group = block - (u64) bit;

	return group;
}

static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
					  u64 bg_blkno)
{
	/* This should work for all block group descriptors as only
	 * the 1st group descriptor of the cluster bitmap is
	 * different. */

	if (bg_blkno == osb->first_cluster_group_blkno)
		return 0;

	/* the rest of the block groups are located at the beginning
	 * of their 1st cluster, so a direct translation just
	 * works. */
	return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
}

static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
{
	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
}

/* This is for local alloc ONLY. Others should use the task-specific
 * apis above. */
int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
				      struct ocfs2_alloc_context *ac);
void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);

/* given a cluster offset, calculate which block group it belongs to
 * and return that block offset. */
u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);

/* somewhat more expensive than our other checks, so use sparingly. */
int ocfs2_check_group_descriptor(struct super_block *sb,
				 struct ocfs2_dinode *di,
				 struct ocfs2_group_desc *gd);
#endif /* _CHAINALLOC_H_ */
Commit	Line	Data
ccd979bd MF	1	/* -- mode: c; c-basic-offset: 8; --
	2	* vim: noexpandtab sw=8 ts=8 sts=0:
	3	*
	4	* suballoc.h
	5	*
	6	* Defines sub allocator api
	7	*
	8	* Copyright (C) 2003, 2004 Oracle. All rights reserved.
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public
	12	* License as published by the Free Software Foundation; either
	13	* version 2 of the License, or (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public
	21	* License along with this program; if not, write to the
	22	* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	23	* Boston, MA 021110-1307, USA.
	24	*/
	25
	26	#ifndef _CHAINALLOC_H_
	27	#define _CHAINALLOC_H_
	28
	29	typedef int (group_search_t)(struct inode *,
	30	struct buffer_head *,
	31	u32,
	32	u32,
	33	u16 *,
	34	u16 *);
	35
	36	struct ocfs2_alloc_context {
	37	struct inode ac_inode; / which bitmap are we allocating from? */
	38	struct buffer_head ac_bh; / file entry bh */
a4a48911	39	u32 ac_alloc_slot; /* which slot are we allocating from? */
ccd979bd MF	40	u32 ac_bits_wanted;
	41	u32 ac_bits_given;
	42	#define OCFS2_AC_USE_LOCAL 1
	43	#define OCFS2_AC_USE_MAIN 2
	44	#define OCFS2_AC_USE_INODE 3
	45	#define OCFS2_AC_USE_META 4
	46	u32 ac_which;
ccd979bd MF	47
	48	/* these are used by the chain search */
	49	u16 ac_chain;
	50	int ac_allow_chain_relink;
	51	group_search_t *ac_group_search;
883d4cae MF	52
883d4cae MF	53	u64 ac_last_group;
ccd979bd MF	54	};
	55
	56	void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
	57	static inline int ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context *ac)
	58	{
	59	return ac->ac_bits_wanted - ac->ac_bits_given;
	60	}
	61
811f933d TM	62	/*
	63	* Please note that the caller must make sure that root_el is the root
	64	* of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
	65	* the result may be wrong.
	66	*/
ccd979bd	67	int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
811f933d	68	struct ocfs2_extent_list *root_el,
ccd979bd MF	69	struct ocfs2_alloc_context **ac);
ccd979bd MF	70	int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
ccd979bd MF	71	struct ocfs2_alloc_context **ac);
ccd979bd MF	72	int ocfs2_reserve_clusters(struct ocfs2_super *osb,
ccd979bd MF	73	u32 bits_wanted,
	74	struct ocfs2_alloc_context **ac);
	75
	76	int ocfs2_claim_metadata(struct ocfs2_super *osb,
1fabe148	77	handle_t *handle,
ccd979bd MF	78	struct ocfs2_alloc_context *ac,
	79	u32 bits_wanted,
	80	u16 *suballoc_bit_start,
	81	u32 *num_bits,
	82	u64 *blkno_start);
	83	int ocfs2_claim_new_inode(struct ocfs2_super *osb,
1fabe148	84	handle_t *handle,
ccd979bd MF	85	struct ocfs2_alloc_context *ac,
	86	u16 *suballoc_bit,
	87	u64 *fe_blkno);
	88	int ocfs2_claim_clusters(struct ocfs2_super *osb,
1fabe148	89	handle_t *handle,
ccd979bd MF	90	struct ocfs2_alloc_context *ac,
	91	u32 min_clusters,
	92	u32 *cluster_start,
	93	u32 *num_clusters);
415cb800 MF	94	/*
	95	* Use this variant of ocfs2_claim_clusters to specify a maxiumum
	96	* number of clusters smaller than the allocation reserved.
	97	*/
	98	int __ocfs2_claim_clusters(struct ocfs2_super *osb,
	99	handle_t *handle,
	100	struct ocfs2_alloc_context *ac,
	101	u32 min_clusters,
	102	u32 max_clusters,
	103	u32 *cluster_start,
	104	u32 *num_clusters);
ccd979bd	105
2b604351 MF	106	int ocfs2_free_suballoc_bits(handle_t *handle,
	107	struct inode *alloc_inode,
	108	struct buffer_head *alloc_bh,
	109	unsigned int start_bit,
	110	u64 bg_blkno,
	111	unsigned int count);
1fabe148	112	int ocfs2_free_dinode(handle_t *handle,
ccd979bd MF	113	struct inode *inode_alloc_inode,
	114	struct buffer_head *inode_alloc_bh,
	115	struct ocfs2_dinode *di);
1fabe148	116	int ocfs2_free_clusters(handle_t *handle,
ccd979bd MF	117	struct inode *bitmap_inode,
	118	struct buffer_head *bitmap_bh,
	119	u64 start_blk,
	120	unsigned int num_clusters);
	121
2b604351 MF	122	static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
	123	{
	124	u64 group = block - (u64) bit;
	125
	126	return group;
	127	}
	128
ccd979bd MF	129	static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
	130	u64 bg_blkno)
	131	{
	132	/* This should work for all block group descriptors as only
	133	* the 1st group descriptor of the cluster bitmap is
	134	* different. */
	135
	136	if (bg_blkno == osb->first_cluster_group_blkno)
	137	return 0;
	138
	139	/* the rest of the block groups are located at the beginning
	140	* of their 1st cluster, so a direct translation just
	141	* works. */
	142	return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
	143	}
	144
	145	static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
	146	{
	147	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	148	return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
	149	}
	150
	151	/* This is for local alloc ONLY. Others should use the task-specific
	152	* apis above. */
	153	int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
	154	struct ocfs2_alloc_context *ac);
9c7af40b	155	void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);
ccd979bd	156
d659072f TM	157	/* given a cluster offset, calculate which block group it belongs to
	158	* and return that block offset. */
	159	u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
	160
	161	/* somewhat more expensive than our other checks, so use sparingly. */
	162	int ocfs2_check_group_descriptor(struct super_block *sb,
	163	struct ocfs2_dinode *di,
	164	struct ocfs2_group_desc *gd);
ccd979bd	165	#endif /* _CHAINALLOC_H_ */