linux-hardened/fs/gfs2/rgrp.h
Steven Whitehouse ff7f4cb461 GFS2: Consolidate free block searching functions
With the recently added block reservation code, an additional function
was added to search for free blocks. This had a restriction of only being
able to search for aligned extents of free blocks. As a result the
allocation patterns when reserving blocks were suboptimal when the
existing allocation of blocks for an inode was not aligned to the same
boundary.

This patch resolves that problem by adding the ability for gfs2_rbm_find
to search for extents of a particular minimum size. We can then use
gfs2_rbm_find for both looking for reservations, and also looking for
free blocks on an individual basis when we actually come to do the
allocation later on. As a result we only need a single set of code
to deal with both situations.

The function gfs2_rbm_from_block() is moved up rgrp.c so that it
occurs before all of its callers.

Many thanks are due to Bob for helping track down the final issue in
this patch. That fix to the rb_tree traversal and to not share
block reservations from a dirctory to its children is included here.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2012-09-24 10:47:26 +01:00

82 lines
3.1 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#ifndef __RGRP_DOT_H__
#define __RGRP_DOT_H__
#include <linux/slab.h>
#include <linux/uaccess.h>
/* Since each block in the file system is represented by two bits in the
* bitmap, one 64-bit word in the bitmap will represent 32 blocks.
* By reserving 32 blocks at a time, we can optimize / shortcut how we search
* through the bitmaps by looking a word at a time.
*/
#define RGRP_RSRV_MINBYTES 8
#define RGRP_RSRV_MINBLKS ((u32)(RGRP_RSRV_MINBYTES * GFS2_NBBY))
struct gfs2_rgrpd;
struct gfs2_sbd;
struct gfs2_holder;
extern void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd);
extern struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, u64 blk, bool exact);
extern struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp);
extern struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd);
extern void gfs2_clear_rgrpd(struct gfs2_sbd *sdp);
extern int gfs2_rindex_update(struct gfs2_sbd *sdp);
extern void gfs2_free_clones(struct gfs2_rgrpd *rgd);
extern int gfs2_rgrp_go_lock(struct gfs2_holder *gh);
extern void gfs2_rgrp_go_unlock(struct gfs2_holder *gh);
extern struct gfs2_alloc *gfs2_alloc_get(struct gfs2_inode *ip);
extern int gfs2_inplace_reserve(struct gfs2_inode *ip, u32 requested);
extern void gfs2_inplace_release(struct gfs2_inode *ip);
extern int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *n,
bool dinode, u64 *generation);
extern int gfs2_rs_alloc(struct gfs2_inode *ip);
extern void gfs2_rs_deltree(struct gfs2_inode *ip, struct gfs2_blkreserv *rs);
extern void gfs2_rs_delete(struct gfs2_inode *ip);
extern void __gfs2_free_blocks(struct gfs2_inode *ip, u64 bstart, u32 blen, int meta);
extern void gfs2_free_meta(struct gfs2_inode *ip, u64 bstart, u32 blen);
extern void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip);
extern void gfs2_unlink_di(struct inode *inode);
extern int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr,
unsigned int type);
struct gfs2_rgrp_list {
unsigned int rl_rgrps;
unsigned int rl_space;
struct gfs2_rgrpd **rl_rgd;
struct gfs2_holder *rl_ghs;
};
extern void gfs2_rlist_add(struct gfs2_inode *ip, struct gfs2_rgrp_list *rlist,
u64 block);
extern void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, unsigned int state);
extern void gfs2_rlist_free(struct gfs2_rgrp_list *rlist);
extern u64 gfs2_ri_total(struct gfs2_sbd *sdp);
extern int gfs2_rgrp_dump(struct seq_file *seq, const struct gfs2_glock *gl);
extern int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset,
struct buffer_head *bh,
const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed);
extern int gfs2_fitrim(struct file *filp, void __user *argp);
/* This is how to tell if a reservation is in the rgrp tree: */
static inline bool gfs2_rs_active(struct gfs2_blkreserv *rs)
{
return rs && !RB_EMPTY_NODE(&rs->rs_node);
}
#endif /* __RGRP_DOT_H__ */