/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2005 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 v.2.
*/
#include <linux/sched.h>
#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 <asm/semaphore.h>
#include "gfs2.h"
#include "lm_interface.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 = jd->jd_inode->u.generic_ip;
struct gfs2_glock *gl = ip->i_gl;
int new = 0;
uint64_t dblock;
uint32_t extlen;
int error;
error = gfs2_block_map(ip, blk, &new, &dblock,
&extlen);
if (error)
return error;
if (!dblock) {
gfs2_consist_inode(ip);
return -EIO;
}
gfs2_meta_ra(gl, dblock, extlen);
error = gfs2_meta_read(gl, dblock, DIO_START | DIO_WAIT, bh);
return error;
}
int gfs2_revoke_add(struct gfs2_sbd *sdp, uint64_t 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, uint64_t 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 *head)
{
struct buffer_head *bh;
struct gfs2_log_header lh;
uint32_t hash;
int error;
error = gfs2_replay_read_block(jd, blk, &bh);
if (error)
return error;
memcpy(&lh, bh->b_data, sizeof(struct gfs2_log_header));
lh.lh_hash = 0;
hash = gfs2_disk_hash((char *)&lh, sizeof(struct gfs2_log_header));
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 *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(jd->jd_inode->u.generic_ip);
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 *head)
{
unsigned int blk = head->lh_blkno;
struct gfs2_log_header 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(jd->jd_inode->u.generic_ip);
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 *head)
{
struct gfs2_log_header lh_1, lh_m;
uint32_t 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_inode *ip = jd->jd_inode->u.generic_ip;
struct gfs2_sbd *sdp = ip->i_sbd;
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 (be16_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
struct gfs2_log_header lh;
error = get_log_header(jd, start, &lh);
if (!error) {
gfs2_replay_incr_blk(sdp, &start);
continue;
}
if (error == 1) {
gfs2_consist_inode(jd->jd_inode->u.generic_ip);
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 *head)
{
struct gfs2_inode *ip = jd->jd_inode->u.generic_ip;
struct gfs2_sbd *sdp = ip->i_sbd;
unsigned int lblock;
int new = 0;
uint64_t dblock;
struct gfs2_log_header *lh;
uint32_t hash;
struct buffer_head *bh;
int error;
lblock = head->lh_blkno;
gfs2_replay_incr_blk(sdp, &lblock);
error = gfs2_block_map(ip, lblock, &new, &dblock, NULL);
if (error)
return error;
if (!dblock) {
gfs2_consist_inode(ip);
return -EIO;
}
bh = sb_getblk(sdp->sd_vfs, dblock);
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_be16(GFS2_METATYPE_LH);
lh->lh_header.mh_format = cpu_to_be16(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
* @wait: Don't return until the journal is clean (or an error is encountered)
*
* 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, int wait)
{
struct gfs2_inode *ip = jd->jd_inode->u.generic_ip;
struct gfs2_sbd *sdp = ip->i_sbd;
struct gfs2_log_header head;
struct gfs2_holder j_gh, ji_gh, t_gh;
unsigned long t;
int ro = 0;
unsigned int pass;
int error;
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 |
((wait) ? 0 : 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;
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_NEVER_RECURSE |
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);
}
gfs2_glock_dq_uninit(&ji_gh);
gfs2_lm_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
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:
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, NO_WAIT);
}
}
