/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 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.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/mempool.h>
#include <linux/gfs2_ondisk.h>
#include <linux/bio.h>
#include <linux/fs.h>
#include "gfs2.h"
#include "incore.h"
#include "inode.h"
#include "glock.h"
#include "log.h"
#include "lops.h"
#include "meta_io.h"
#include "recovery.h"
#include "rgrp.h"
#include "trans.h"
#include "util.h"
#include "trace_gfs2.h"
/**
* gfs2_pin - Pin a buffer in memory
* @sdp: The superblock
* @bh: The buffer to be pinned
*
* The log lock must be held when calling this function
*/
static void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh)
{
struct gfs2_bufdata *bd;
BUG_ON(!current->journal_info);
clear_buffer_dirty(bh);
if (test_set_buffer_pinned(bh))
gfs2_assert_withdraw(sdp, 0);
if (!buffer_uptodate(bh))
gfs2_io_error_bh(sdp, bh);
bd = bh->b_private;
/* If this buffer is in the AIL and it has already been written
* to in-place disk block, remove it from the AIL.
*/
spin_lock(&sdp->sd_ail_lock);
if (bd->bd_ail)
list_move(&bd->bd_ail_st_list, &bd->bd_ail->ai_ail2_list);
spin_unlock(&sdp->sd_ail_lock);
get_bh(bh);
atomic_inc(&sdp->sd_log_pinned);
trace_gfs2_pin(bd, 1);
}
static bool buffer_is_rgrp(const struct gfs2_bufdata *bd)
{
return bd->bd_gl->gl_name.ln_type == LM_TYPE_RGRP;
}
static void maybe_release_space(struct gfs2_bufdata *bd)
{
struct gfs2_glock *gl = bd->bd_gl;
struct gfs2_sbd *sdp = gl->gl_sbd;
struct gfs2_rgrpd *rgd = gl->gl_object;
unsigned int index = bd->bd_bh->b_blocknr - gl->gl_name.ln_number;
struct gfs2_bitmap *bi = rgd->rd_bits + index;
if (bi->bi_clone == 0)
return;
if (sdp->sd_args.ar_discard)
gfs2_rgrp_send_discards(sdp, rgd->rd_data0, bd->bd_bh, bi, 1, NULL);
memcpy(bi->bi_clone + bi->bi_offset,
bd->bd_bh->b_data + bi->bi_offset, bi->bi_len);
clear_bit(GBF_FULL, &bi->bi_flags);
rgd->rd_free_clone = rgd->rd_free;
}
/**
* gfs2_unpin - Unpin a buffer
* @sdp: the filesystem the buffer belongs to
* @bh: The buffer to unpin
* @ai:
* @flags: The inode dirty flags
*
*/
static void gfs2_unpin(struct gfs2_sbd *sdp, struct buffer_head *bh,
struct gfs2_ail *ai)
{
struct gfs2_bufdata *bd = bh->b_private;
BUG_ON(!buffer_uptodate(bh));
BUG_ON(!buffer_pinned(bh));
lock_buffer(bh);
mark_buffer_dirty(bh);
clear_buffer_pinned(bh);
if (buffer_is_rgrp(bd))
maybe_release_space(bd);
spin_lock(&sdp->sd_ail_lock);
if (bd->bd_ail) {
list_del(&bd->bd_ail_st_list);
brelse(bh);
} else {
struct gfs2_glock *gl = bd->bd_gl;
list_add(&bd->bd_ail_gl_list, &gl->gl_ail_list);
atomic_inc(&gl->gl_ail_count);
}
bd->bd_ail = ai;
list_add(&bd->bd_ail_st_list, &ai->ai_ail1_list);
spin_unlock(&sdp->sd_ail_lock);
clear_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
trace_gfs2_pin(bd, 0);
unlock_buffer(bh);
atomic_dec(&sdp->sd_log_pinned);
}
static void gfs2_log_incr_head(struct gfs2_sbd *sdp)
{
BUG_ON((sdp->sd_log_flush_head == sdp->sd_log_tail) &&
(sdp->sd_log_flush_head != sdp->sd_log_head));
if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
sdp->sd_log_flush_head = 0;
sdp->sd_log_flush_wrapped = 1;
}
}
static u64 gfs2_log_bmap(struct gfs2_sbd *sdp)
{
unsigned int lbn = sdp->sd_log_flush_head;
struct gfs2_journal_extent *je;
u64 block;
list_for_each_entry(je, &sdp->sd_jdesc->extent_list, extent_list) {
if (lbn >= je->lblock && lbn < je->lblock + je->blocks) {
block = je->dblock + lbn - je->lblock;
gfs2_log_incr_head(sdp);
return block;
}
}
return -1;
}
/**
* gfs2_end_log_write_bh - end log write of pagecache data with buffers
* @sdp: The superblock
* @bvec: The bio_vec
* @error: The i/o status
*