[net-next-2.6.git] / fs / gfs2 / recovery.c

/*
 * 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/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/lm_interface.h>

#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "glops.h"
#include "lm.h"
#include "lops.h"
#include "meta_io.h"
#include "recovery.h"
#include "super.h"
#include "util.h"
#include "dir.h"

int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
			   struct buffer_head **bh)
{
	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
	struct gfs2_glock *gl = ip->i_gl;
	int new = 0;
	u64 dblock;
	u32 extlen;
	int error;

	error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen);
	if (error)
		return error;
	if (!dblock) {
		gfs2_consist_inode(ip);
		return -EIO;
	}

	*bh = gfs2_meta_ra(gl, dblock, extlen);

	return error;
}

int gfs2_revoke_add(struct gfs2_sbd *sdp, u64 blkno, unsigned int where)
{
	struct list_head *head = &sdp->sd_revoke_list;
	struct gfs2_revoke_replay *rr;
	int found = 0;

	list_for_each_entry(rr, head, rr_list) {
		if (rr->rr_blkno == blkno) {
			found = 1;
			break;
		}
	}

	if (found) {
		rr->rr_where = where;
		return 0;
	}

	rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_KERNEL);
	if (!rr)
		return -ENOMEM;

	rr->rr_blkno = blkno;
	rr->rr_where = where;
	list_add(&rr->rr_list, head);

	return 1;
}

int gfs2_revoke_check(struct gfs2_sbd *sdp, u64 blkno, unsigned int where)
{
	struct gfs2_revoke_replay *rr;
	int wrap, a, b, revoke;
	int found = 0;

	list_for_each_entry(rr, &sdp->sd_revoke_list, rr_list) {
		if (rr->rr_blkno == blkno) {
			found = 1;
			break;
		}
	}

	if (!found)
		return 0;

	wrap = (rr->rr_where < sdp->sd_replay_tail);
	a = (sdp->sd_replay_tail < where);
	b = (where < rr->rr_where);
	revoke = (wrap) ? (a || b) : (a && b);

	return revoke;
}

void gfs2_revoke_clean(struct gfs2_sbd *sdp)
{
	struct list_head *head = &sdp->sd_revoke_list;
	struct gfs2_revoke_replay *rr;

	while (!list_empty(head)) {
		rr = list_entry(head->next, struct gfs2_revoke_replay, rr_list);
		list_del(&rr->rr_list);
		kfree(rr);
	}
}

/**
 * get_log_header - read the log header for a given segment
 * @jd: the journal
 * @blk: the block to look at
 * @lh: the log header to return
 *
 * Read the log header for a given segement in a given journal.  Do a few
 * sanity checks on it.
 *
 * Returns: 0 on success,
 *          1 if the header was invalid or incomplete,
 *          errno on error
 */

static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
			  struct gfs2_log_header_host *head)
{
	struct buffer_head *bh;
	struct gfs2_log_header_host lh;
	const u32 nothing = 0;
	u32 hash;
	int error;

	error = gfs2_replay_read_block(jd, blk, &bh);
	if (error)
		return error;

	hash = crc32_le((u32)~0, bh->b_data, sizeof(struct gfs2_log_header) -
					     sizeof(u32));
	hash = crc32_le(hash, (unsigned char const *)&nothing, sizeof(nothing));
	hash ^= (u32)~0;
	gfs2_log_header_in(&lh, bh->b_data);
	brelse(bh);

	if (lh.lh_header.mh_magic != GFS2_MAGIC ||
	    lh.lh_header.mh_type != GFS2_METATYPE_LH ||
	    lh.lh_blkno != blk || lh.lh_hash != hash)
		return 1;

	*head = lh;

	return 0;
}

/**
 * find_good_lh - find a good log header
 * @jd: the journal
 * @blk: the segment to start searching from
 * @lh: the log header to fill in
 * @forward: if true search forward in the log, else search backward
 *
 * Call get_log_header() to get a log header for a segment, but if the
 * segment is bad, either scan forward or backward until we find a good one.
 *
 * Returns: errno
 */

static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk,
			struct gfs2_log_header_host *head)
{
	unsigned int orig_blk = *blk;
	int error;

	for (;;) {
		error = get_log_header(jd, *blk, head);
		if (error <= 0)
			return error;

		if (++*blk == jd->jd_blocks)
			*blk = 0;

		if (*blk == orig_blk) {
			gfs2_consist_inode(GFS2_I(jd->jd_inode));
			return -EIO;
		}
	}
}

/**
 * jhead_scan - make sure we've found the head of the log
 * @jd: the journal
 * @head: this is filled in with the log descriptor of the head
 *
 * At this point, seg and lh should be either the head of the log or just
 * before.  Scan forward until we find the head.
 *
 * Returns: errno
 */

static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
{
	unsigned int blk = head->lh_blkno;
	struct gfs2_log_header_host lh;
	int error;

	for (;;) {
		if (++blk == jd->jd_blocks)
			blk = 0;

		error = get_log_header(jd, blk, &lh);
		if (error < 0)
			return error;
		if (error == 1)
			continue;

		if (lh.lh_sequence == head->lh_sequence) {
			gfs2_consist_inode(GFS2_I(jd->jd_inode));
			return -EIO;
		}
		if (lh.lh_sequence < head->lh_sequence)
			break;

		*head = lh;
	}

	return 0;
}

/**
 * gfs2_find_jhead - find the head of a log
 * @jd: the journal
 * @head: the log descriptor for the head of the log is returned here
 *
 * Do a binary search of a journal and find the valid log entry with the
 * highest sequence number.  (i.e. the log head)
 *
 * Returns: errno
 */

int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
{
	struct gfs2_log_header_host lh_1, lh_m;
	u32 blk_1, blk_2, blk_m;
	int error;

	blk_1 = 0;
	blk_2 = jd->jd_blocks - 1;

	for (;;) {
		blk_m = (blk_1 + blk_2) / 2;

		error = find_good_lh(jd, &blk_1, &lh_1);
		if (error)
			return error;

		error = find_good_lh(jd, &blk_m, &lh_m);
		if (error)
			return error;

		if (blk_1 == blk_m || blk_m == blk_2)
			break;

		if (lh_1.lh_sequence <= lh_m.lh_sequence)
			blk_1 = blk_m;
		else
			blk_2 = blk_m;
	}

	error = jhead_scan(jd, &lh_1);
	if (error)
		return error;

	*head = lh_1;

	return error;
}

/**
 * foreach_descriptor - go through the active part of the log
 * @jd: the journal
 * @start: the first log header in the active region
 * @end: the last log header (don't process the contents of this entry))
 *
 * Call a given function once for every log descriptor in the active
 * portion of the log.
 *
 * Returns: errno
 */

static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start,
			      unsigned int end, int pass)
{
	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
	struct buffer_head *bh;
	struct gfs2_log_descriptor *ld;
	int error = 0;
	u32 length;
	__be64 *ptr;
	unsigned int offset = sizeof(struct gfs2_log_descriptor);
	offset += sizeof(__be64) - 1;
	offset &= ~(sizeof(__be64) - 1);

	while (start != end) {
		error = gfs2_replay_read_block(jd, start, &bh);
		if (error)
			return error;
		if (gfs2_meta_check(sdp, bh)) {
			brelse(bh);
			return -EIO;
		}
		ld = (struct gfs2_log_descriptor *)bh->b_data;
		length = be32_to_cpu(ld->ld_length);

		if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
			struct gfs2_log_header_host lh;
			error = get_log_header(jd, start, &lh);
			if (!error) {
				gfs2_replay_incr_blk(sdp, &start);
				brelse(bh);
				continue;
			}
			if (error == 1) {
				gfs2_consist_inode(GFS2_I(jd->jd_inode));
				error = -EIO;
			}
			brelse(bh);
			return error;
		} else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
			brelse(bh);
			return -EIO;
		}
		ptr = (__be64 *)(bh->b_data + offset);
		error = lops_scan_elements(jd, start, ld, ptr, pass);
		if (error) {
			brelse(bh);
			return error;
		}

		while (length--)
			gfs2_replay_incr_blk(sdp, &start);

		brelse(bh);
	}

	return 0;
}

/**
 * clean_journal - mark a dirty journal as being clean
 * @sdp: the filesystem
 * @jd: the journal
 * @gl: the journal's glock
 * @head: the head journal to start from
 *
 * Returns: errno
 */

static int clean_journal(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
{
	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
	unsigned int lblock;
	struct gfs2_log_header *lh;
	u32 hash;
	struct buffer_head *bh;
	int error;
	struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };

	lblock = head->lh_blkno;
	gfs2_replay_incr_blk(sdp, &lblock);
	bh_map.b_size = 1 << ip->i_inode.i_blkbits;
	error = gfs2_block_map(&ip->i_inode, lblock, 0, &bh_map);
	if (error)
		return error;
	if (!bh_map.b_blocknr) {
		gfs2_consist_inode(ip);
		return -EIO;
	}

	bh = sb_getblk(sdp->sd_vfs, bh_map.b_blocknr);
	lock_buffer(bh);
	memset(bh->b_data, 0, bh->b_size);
	set_buffer_uptodate(bh);
	clear_buffer_dirty(bh);
	unlock_buffer(bh);

	lh = (struct gfs2_log_header *)bh->b_data;
	memset(lh, 0, sizeof(struct gfs2_log_header));
	lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
	lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
	lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
	lh->lh_sequence = cpu_to_be64(head->lh_sequence + 1);
	lh->lh_flags = cpu_to_be32(GFS2_LOG_HEAD_UNMOUNT);
	lh->lh_blkno = cpu_to_be32(lblock);
	hash = gfs2_disk_hash((const char *)lh, sizeof(struct gfs2_log_header));
	lh->lh_hash = cpu_to_be32(hash);

	set_buffer_dirty(bh);
	if (sync_dirty_buffer(bh))
		gfs2_io_error_bh(sdp, bh);
	brelse(bh);

	return error;
}

/**
 * gfs2_recover_journal - recovery a given journal
 * @jd: the struct gfs2_jdesc describing the journal
 *
 * Acquire the journal's lock, check to see if the journal is clean, and
 * do recovery if necessary.
 *
 * Returns: errno
 */

int gfs2_recover_journal(struct gfs2_jdesc *jd)
{
	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
	struct gfs2_log_header_host head;
	struct gfs2_holder j_gh, ji_gh, t_gh;
	unsigned long t;
	int ro = 0;
	unsigned int pass;
	int error;

	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
		fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
			jd->jd_jid);

		/* Aquire the journal lock so we can do recovery */

		error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
					  LM_ST_EXCLUSIVE,
					  LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
					  &j_gh);
		switch (error) {
		case 0:
			break;

		case GLR_TRYFAILED:
			fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
			error = 0;

		default:
			goto fail;
		};

		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
					   LM_FLAG_NOEXP, &ji_gh);
		if (error)
			goto fail_gunlock_j;
	} else {
		fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
	}

	fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);

	error = gfs2_jdesc_check(jd);
	if (error)
		goto fail_gunlock_ji;

	error = gfs2_find_jhead(jd, &head);
	if (error)
		goto fail_gunlock_ji;

	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
		fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
			jd->jd_jid);

		t = jiffies;

		/* Acquire a shared hold on the transaction lock */

		error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
					   LM_FLAG_NOEXP | LM_FLAG_PRIORITY |
					   GL_NOCANCEL | GL_NOCACHE, &t_gh);
		if (error)
			goto fail_gunlock_ji;

		if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
			if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
				ro = 1;
		} else {
			if (sdp->sd_vfs->s_flags & MS_RDONLY)
				ro = 1;
		}

		if (ro) {
			fs_warn(sdp, "jid=%u: Can't replay: read-only FS\n",
				jd->jd_jid);
			error = -EROFS;
			goto fail_gunlock_tr;
		}

		fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid);

		for (pass = 0; pass < 2; pass++) {
			lops_before_scan(jd, &head, pass);
			error = foreach_descriptor(jd, head.lh_tail,
						   head.lh_blkno, pass);
			lops_after_scan(jd, error, pass);
			if (error)
				goto fail_gunlock_tr;
		}

		error = clean_journal(jd, &head);
		if (error)
			goto fail_gunlock_tr;

		gfs2_glock_dq_uninit(&t_gh);
		t = DIV_ROUND_UP(jiffies - t, HZ);
		fs_info(sdp, "jid=%u: Journal replayed in %lus\n",
			jd->jd_jid, t);
	}

	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid)
		gfs2_glock_dq_uninit(&ji_gh);

	gfs2_lm_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);

	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid)
		gfs2_glock_dq_uninit(&j_gh);

	fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
	return 0;

fail_gunlock_tr:
	gfs2_glock_dq_uninit(&t_gh);
fail_gunlock_ji:
	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
		gfs2_glock_dq_uninit(&ji_gh);
fail_gunlock_j:
		gfs2_glock_dq_uninit(&j_gh);
	}

	fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");

fail:
	gfs2_lm_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
	return error;
}

/**
 * gfs2_check_journals - Recover any dirty journals
 * @sdp: the filesystem
 *
 */

void gfs2_check_journals(struct gfs2_sbd *sdp)
{
	struct gfs2_jdesc *jd;

	for (;;) {
		jd = gfs2_jdesc_find_dirty(sdp);
		if (!jd)
			break;

		if (jd != sdp->sd_jdesc)
			gfs2_recover_journal(jd);
	}
}
Commit	Line	Data
b3b94faa DT	1	/*
b3b94faa DT	2	* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3a8a9a10	3	* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
b3b94faa DT	4	*
	5	* This copyrighted material is made available to anyone wishing to use,
	6	* modify, copy, or redistribute it subject to the terms and conditions
e9fc2aa0	7	* of the GNU General Public License version 2.
b3b94faa DT	8	*/
b3b94faa DT	9
b3b94faa DT	10	#include <linux/slab.h>
	11	#include <linux/spinlock.h>
	12	#include <linux/completion.h>
	13	#include <linux/buffer_head.h>
5c676f6d	14	#include <linux/gfs2_ondisk.h>
71b86f56	15	#include <linux/crc32.h>
7d308590	16	#include <linux/lm_interface.h>
b3b94faa DT	17
b3b94faa DT	18	#include "gfs2.h"
5c676f6d	19	#include "incore.h"
b3b94faa DT	20	#include "bmap.h"
	21	#include "glock.h"
	22	#include "glops.h"
	23	#include "lm.h"
	24	#include "lops.h"
	25	#include "meta_io.h"
	26	#include "recovery.h"
	27	#include "super.h"
5c676f6d	28	#include "util.h"
71b86f56	29	#include "dir.h"
b3b94faa DT	30
	31	int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
	32	struct buffer_head **bh)
	33	{
feaa7bba	34	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
5c676f6d	35	struct gfs2_glock *gl = ip->i_gl;
b3b94faa	36	int new = 0;
cd915493 SW	37	u64 dblock;
cd915493 SW	38	u32 extlen;
b3b94faa DT	39	int error;
b3b94faa DT	40
feaa7bba	41	error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen);
b3b94faa DT	42	if (error)
	43	return error;
	44	if (!dblock) {
5c676f6d	45	gfs2_consist_inode(ip);
b3b94faa DT	46	return -EIO;
	47	}
	48
7276b3b0	49	*bh = gfs2_meta_ra(gl, dblock, extlen);
b3b94faa DT	50
	51	return error;
	52	}
	53
cd915493	54	int gfs2_revoke_add(struct gfs2_sbd *sdp, u64 blkno, unsigned int where)
b3b94faa DT	55	{
	56	struct list_head *head = &sdp->sd_revoke_list;
	57	struct gfs2_revoke_replay *rr;
	58	int found = 0;
	59
	60	list_for_each_entry(rr, head, rr_list) {
	61	if (rr->rr_blkno == blkno) {
	62	found = 1;
	63	break;
	64	}
	65	}
	66
	67	if (found) {
	68	rr->rr_where = where;
	69	return 0;
	70	}
	71
	72	rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_KERNEL);
	73	if (!rr)
	74	return -ENOMEM;
	75
	76	rr->rr_blkno = blkno;
	77	rr->rr_where = where;
	78	list_add(&rr->rr_list, head);
	79
	80	return 1;
	81	}
	82
cd915493	83	int gfs2_revoke_check(struct gfs2_sbd *sdp, u64 blkno, unsigned int where)
b3b94faa DT	84	{
	85	struct gfs2_revoke_replay *rr;
	86	int wrap, a, b, revoke;
	87	int found = 0;
	88
	89	list_for_each_entry(rr, &sdp->sd_revoke_list, rr_list) {
	90	if (rr->rr_blkno == blkno) {
	91	found = 1;
	92	break;
	93	}
	94	}
	95
	96	if (!found)
	97	return 0;
	98
	99	wrap = (rr->rr_where < sdp->sd_replay_tail);
	100	a = (sdp->sd_replay_tail < where);
	101	b = (where < rr->rr_where);
	102	revoke = (wrap) ? (a \|\| b) : (a && b);
	103
	104	return revoke;
	105	}
	106
	107	void gfs2_revoke_clean(struct gfs2_sbd *sdp)
	108	{
	109	struct list_head *head = &sdp->sd_revoke_list;
	110	struct gfs2_revoke_replay *rr;
	111
	112	while (!list_empty(head)) {
	113	rr = list_entry(head->next, struct gfs2_revoke_replay, rr_list);
	114	list_del(&rr->rr_list);
	115	kfree(rr);
	116	}
	117	}
	118
	119	/**
	120	* get_log_header - read the log header for a given segment
	121	* @jd: the journal
	122	* @blk: the block to look at
	123	* @lh: the log header to return
	124	*
	125	* Read the log header for a given segement in a given journal. Do a few
	126	* sanity checks on it.
	127	*
	128	* Returns: 0 on success,
	129	* 1 if the header was invalid or incomplete,
	130	* errno on error
	131	*/
	132
	133	static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
55167622	134	struct gfs2_log_header_host *head)
b3b94faa DT	135	{
b3b94faa DT	136	struct buffer_head *bh;
55167622	137	struct gfs2_log_header_host lh;
887bc5d0	138	const u32 nothing = 0;
cd915493	139	u32 hash;
b3b94faa DT	140	int error;
	141
	142	error = gfs2_replay_read_block(jd, blk, &bh);
	143	if (error)
	144	return error;
	145
2a2c9824 SW	146	hash = crc32_le((u32)~0, bh->b_data, sizeof(struct gfs2_log_header) -
	147	sizeof(u32));
	148	hash = crc32_le(hash, (unsigned char const *)&nothing, sizeof(nothing));
	149	hash ^= (u32)~0;
b3b94faa	150	gfs2_log_header_in(&lh, bh->b_data);
b3b94faa DT	151	brelse(bh);
	152
	153	if (lh.lh_header.mh_magic != GFS2_MAGIC \|\|
	154	lh.lh_header.mh_type != GFS2_METATYPE_LH \|\|
59a1cc6b	155	lh.lh_blkno != blk \|\| lh.lh_hash != hash)
b3b94faa DT	156	return 1;
	157
	158	*head = lh;
	159
	160	return 0;
	161	}
	162
	163	/**
	164	* find_good_lh - find a good log header
	165	* @jd: the journal
	166	* @blk: the segment to start searching from
	167	* @lh: the log header to fill in
	168	* @forward: if true search forward in the log, else search backward
	169	*
	170	* Call get_log_header() to get a log header for a segment, but if the
	171	* segment is bad, either scan forward or backward until we find a good one.
	172	*
	173	* Returns: errno
	174	*/
	175
	176	static int find_good_lh(struct gfs2_jdesc jd, unsigned int blk,
55167622	177	struct gfs2_log_header_host *head)
b3b94faa DT	178	{
	179	unsigned int orig_blk = *blk;
	180	int error;
	181
	182	for (;;) {
	183	error = get_log_header(jd, *blk, head);
	184	if (error <= 0)
	185	return error;
	186
	187	if (++*blk == jd->jd_blocks)
	188	*blk = 0;
	189
	190	if (*blk == orig_blk) {
feaa7bba	191	gfs2_consist_inode(GFS2_I(jd->jd_inode));
b3b94faa DT	192	return -EIO;
	193	}
	194	}
	195	}
	196
	197	/**
	198	* jhead_scan - make sure we've found the head of the log
	199	* @jd: the journal
	200	* @head: this is filled in with the log descriptor of the head
	201	*
	202	* At this point, seg and lh should be either the head of the log or just
	203	* before. Scan forward until we find the head.
	204	*
	205	* Returns: errno
	206	*/
	207
55167622	208	static int jhead_scan(struct gfs2_jdesc jd, struct gfs2_log_header_host head)
b3b94faa DT	209	{
b3b94faa DT	210	unsigned int blk = head->lh_blkno;
55167622	211	struct gfs2_log_header_host lh;
b3b94faa DT	212	int error;
	213
	214	for (;;) {
	215	if (++blk == jd->jd_blocks)
	216	blk = 0;
	217
	218	error = get_log_header(jd, blk, &lh);
	219	if (error < 0)
	220	return error;
	221	if (error == 1)
	222	continue;
	223
	224	if (lh.lh_sequence == head->lh_sequence) {
feaa7bba	225	gfs2_consist_inode(GFS2_I(jd->jd_inode));
b3b94faa DT	226	return -EIO;
	227	}
	228	if (lh.lh_sequence < head->lh_sequence)
	229	break;
	230
	231	*head = lh;
	232	}
	233
	234	return 0;
	235	}
	236
	237	/**
	238	* gfs2_find_jhead - find the head of a log
	239	* @jd: the journal
	240	* @head: the log descriptor for the head of the log is returned here
	241	*
	242	* Do a binary search of a journal and find the valid log entry with the
	243	* highest sequence number. (i.e. the log head)
	244	*
	245	* Returns: errno
	246	*/
	247
55167622	248	int gfs2_find_jhead(struct gfs2_jdesc jd, struct gfs2_log_header_host head)
b3b94faa	249	{
55167622	250	struct gfs2_log_header_host lh_1, lh_m;
cd915493	251	u32 blk_1, blk_2, blk_m;
b3b94faa DT	252	int error;
	253
	254	blk_1 = 0;
	255	blk_2 = jd->jd_blocks - 1;
	256
	257	for (;;) {
	258	blk_m = (blk_1 + blk_2) / 2;
	259
	260	error = find_good_lh(jd, &blk_1, &lh_1);
	261	if (error)
	262	return error;
	263
	264	error = find_good_lh(jd, &blk_m, &lh_m);
	265	if (error)
	266	return error;
	267
	268	if (blk_1 == blk_m \|\| blk_m == blk_2)
	269	break;
	270
	271	if (lh_1.lh_sequence <= lh_m.lh_sequence)
	272	blk_1 = blk_m;
	273	else
	274	blk_2 = blk_m;
	275	}
	276
	277	error = jhead_scan(jd, &lh_1);
	278	if (error)
	279	return error;
	280
	281	*head = lh_1;
	282
	283	return error;
	284	}
	285
	286	/**
	287	* foreach_descriptor - go through the active part of the log
	288	* @jd: the journal
	289	* @start: the first log header in the active region
	290	* @end: the last log header (don't process the contents of this entry))
	291	*
	292	* Call a given function once for every log descriptor in the active
	293	* portion of the log.
	294	*
	295	* Returns: errno
	296	*/
	297
	298	static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start,
	299	unsigned int end, int pass)
	300	{
feaa7bba	301	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
b3b94faa DT	302	struct buffer_head *bh;
	303	struct gfs2_log_descriptor *ld;
	304	int error = 0;
	305	u32 length;
	306	__be64 *ptr;
	307	unsigned int offset = sizeof(struct gfs2_log_descriptor);
a67cdbd4 SW	308	offset += sizeof(__be64) - 1;
a67cdbd4 SW	309	offset &= ~(sizeof(__be64) - 1);
b3b94faa DT	310
	311	while (start != end) {
	312	error = gfs2_replay_read_block(jd, start, &bh);
	313	if (error)
	314	return error;
	315	if (gfs2_meta_check(sdp, bh)) {
	316	brelse(bh);
	317	return -EIO;
	318	}
	319	ld = (struct gfs2_log_descriptor *)bh->b_data;
	320	length = be32_to_cpu(ld->ld_length);
	321
e3167ded	322	if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
55167622	323	struct gfs2_log_header_host lh;
b3b94faa DT	324	error = get_log_header(jd, start, &lh);
	325	if (!error) {
	326	gfs2_replay_incr_blk(sdp, &start);
88721877	327	brelse(bh);
b3b94faa DT	328	continue;
	329	}
	330	if (error == 1) {
feaa7bba	331	gfs2_consist_inode(GFS2_I(jd->jd_inode));
b3b94faa DT	332	error = -EIO;
	333	}
	334	brelse(bh);
	335	return error;
	336	} else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
	337	brelse(bh);
	338	return -EIO;
	339	}
	340	ptr = (__be64 *)(bh->b_data + offset);
	341	error = lops_scan_elements(jd, start, ld, ptr, pass);
	342	if (error) {
	343	brelse(bh);
	344	return error;
	345	}
	346
	347	while (length--)
	348	gfs2_replay_incr_blk(sdp, &start);
	349
	350	brelse(bh);
	351	}
	352
	353	return 0;
	354	}
	355
	356	/**
	357	* clean_journal - mark a dirty journal as being clean
	358	* @sdp: the filesystem
	359	* @jd: the journal
	360	* @gl: the journal's glock
	361	* @head: the head journal to start from
	362	*
	363	* Returns: errno
	364	*/
	365
55167622	366	static int clean_journal(struct gfs2_jdesc jd, struct gfs2_log_header_host head)
b3b94faa	367	{
feaa7bba SW	368	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
feaa7bba SW	369	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
b3b94faa	370	unsigned int lblock;
b3b94faa	371	struct gfs2_log_header *lh;
cd915493	372	u32 hash;
b3b94faa DT	373	struct buffer_head *bh;
b3b94faa DT	374	int error;
23591256	375	struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
fd88de56	376
b3b94faa DT	377	lblock = head->lh_blkno;
b3b94faa DT	378	gfs2_replay_incr_blk(sdp, &lblock);
23591256 SW	379	bh_map.b_size = 1 << ip->i_inode.i_blkbits;
23591256 SW	380	error = gfs2_block_map(&ip->i_inode, lblock, 0, &bh_map);
b3b94faa DT	381	if (error)
b3b94faa DT	382	return error;
7a6bbacb	383	if (!bh_map.b_blocknr) {
b3b94faa DT	384	gfs2_consist_inode(ip);
	385	return -EIO;
	386	}
	387
7a6bbacb	388	bh = sb_getblk(sdp->sd_vfs, bh_map.b_blocknr);
b3b94faa DT	389	lock_buffer(bh);
	390	memset(bh->b_data, 0, bh->b_size);
	391	set_buffer_uptodate(bh);
	392	clear_buffer_dirty(bh);
	393	unlock_buffer(bh);
	394
	395	lh = (struct gfs2_log_header *)bh->b_data;
	396	memset(lh, 0, sizeof(struct gfs2_log_header));
	397	lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
88721877	398	lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
e3167ded	399	lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
b3b94faa DT	400	lh->lh_sequence = cpu_to_be64(head->lh_sequence + 1);
	401	lh->lh_flags = cpu_to_be32(GFS2_LOG_HEAD_UNMOUNT);
	402	lh->lh_blkno = cpu_to_be32(lblock);
	403	hash = gfs2_disk_hash((const char *)lh, sizeof(struct gfs2_log_header));
	404	lh->lh_hash = cpu_to_be32(hash);
	405
	406	set_buffer_dirty(bh);
	407	if (sync_dirty_buffer(bh))
	408	gfs2_io_error_bh(sdp, bh);
	409	brelse(bh);
	410
	411	return error;
	412	}
	413
	414	/**
	415	* gfs2_recover_journal - recovery a given journal
	416	* @jd: the struct gfs2_jdesc describing the journal
b3b94faa DT	417	*
	418	* Acquire the journal's lock, check to see if the journal is clean, and
	419	* do recovery if necessary.
	420	*
	421	* Returns: errno
	422	*/
	423
c63e31c2	424	int gfs2_recover_journal(struct gfs2_jdesc *jd)
b3b94faa	425	{
feaa7bba SW	426	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
feaa7bba SW	427	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
55167622	428	struct gfs2_log_header_host head;
b3b94faa DT	429	struct gfs2_holder j_gh, ji_gh, t_gh;
	430	unsigned long t;
	431	int ro = 0;
	432	unsigned int pass;
	433	int error;
	434
5965b1f4 SW	435	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
	436	fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
	437	jd->jd_jid);
b3b94faa	438
5965b1f4	439	/* Aquire the journal lock so we can do recovery */
b3b94faa	440
5965b1f4 SW	441	error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
	442	LM_ST_EXCLUSIVE,
	443	LM_FLAG_NOEXP \| LM_FLAG_TRY \| GL_NOCACHE,
	444	&j_gh);
	445	switch (error) {
	446	case 0:
	447	break;
907b9bce	448
5965b1f4 SW	449	case GLR_TRYFAILED:
	450	fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
	451	error = 0;
907b9bce	452
5965b1f4 SW	453	default:
	454	goto fail;
	455	};
b3b94faa	456
5965b1f4 SW	457	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
	458	LM_FLAG_NOEXP, &ji_gh);
	459	if (error)
	460	goto fail_gunlock_j;
	461	} else {
	462	fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
	463	}
b3b94faa DT	464
	465	fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
	466
	467	error = gfs2_jdesc_check(jd);
	468	if (error)
	469	goto fail_gunlock_ji;
	470
	471	error = gfs2_find_jhead(jd, &head);
	472	if (error)
	473	goto fail_gunlock_ji;
	474
	475	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
	476	fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
	477	jd->jd_jid);
	478
	479	t = jiffies;
	480
	481	/* Acquire a shared hold on the transaction lock */
	482
59a1cc6b	483	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
5965b1f4	484	LM_FLAG_NOEXP \| LM_FLAG_PRIORITY \|
59a1cc6b	485	GL_NOCANCEL \| GL_NOCACHE, &t_gh);
b3b94faa DT	486	if (error)
	487	goto fail_gunlock_ji;
	488
	489	if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
	490	if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
	491	ro = 1;
	492	} else {
	493	if (sdp->sd_vfs->s_flags & MS_RDONLY)
	494	ro = 1;
	495	}
	496
	497	if (ro) {
	498	fs_warn(sdp, "jid=%u: Can't replay: read-only FS\n",
	499	jd->jd_jid);
	500	error = -EROFS;
	501	goto fail_gunlock_tr;
	502	}
	503
	504	fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid);
	505
	506	for (pass = 0; pass < 2; pass++) {
	507	lops_before_scan(jd, &head, pass);
	508	error = foreach_descriptor(jd, head.lh_tail,
	509	head.lh_blkno, pass);
	510	lops_after_scan(jd, error, pass);
	511	if (error)
	512	goto fail_gunlock_tr;
	513	}
	514
	515	error = clean_journal(jd, &head);
	516	if (error)
	517	goto fail_gunlock_tr;
	518
	519	gfs2_glock_dq_uninit(&t_gh);
5c676f6d	520	t = DIV_ROUND_UP(jiffies - t, HZ);
b3b94faa DT	521	fs_info(sdp, "jid=%u: Journal replayed in %lus\n",
	522	jd->jd_jid, t);
	523	}
	524
5965b1f4 SW	525	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid)
5965b1f4 SW	526	gfs2_glock_dq_uninit(&ji_gh);
b3b94faa DT	527
	528	gfs2_lm_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
	529
5965b1f4 SW	530	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid)
5965b1f4 SW	531	gfs2_glock_dq_uninit(&j_gh);
b3b94faa DT	532
b3b94faa DT	533	fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
b3b94faa DT	534	return 0;
b3b94faa DT	535
5965b1f4	536	fail_gunlock_tr:
b3b94faa	537	gfs2_glock_dq_uninit(&t_gh);
5965b1f4 SW	538	fail_gunlock_ji:
	539	if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
	540	gfs2_glock_dq_uninit(&ji_gh);
	541	fail_gunlock_j:
	542	gfs2_glock_dq_uninit(&j_gh);
	543	}
b3b94faa DT	544
	545	fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
	546
5965b1f4	547	fail:
b3b94faa	548	gfs2_lm_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
b3b94faa DT	549	return error;
	550	}
	551
	552	/**
	553	* gfs2_check_journals - Recover any dirty journals
	554	* @sdp: the filesystem
	555	*
	556	*/
	557
	558	void gfs2_check_journals(struct gfs2_sbd *sdp)
	559	{
	560	struct gfs2_jdesc *jd;
	561
	562	for (;;) {
	563	jd = gfs2_jdesc_find_dirty(sdp);
	564	if (!jd)
	565	break;
	566
	567	if (jd != sdp->sd_jdesc)
c63e31c2	568	gfs2_recover_journal(jd);
b3b94faa DT	569	}
	570	}
	571