debugfs: clean up feature test macros with predicate functions

[thirdparty/e2fsprogs.git] / debugfs / journal.c

/*
 * journal.c --- code for handling the "ext3" journal
 *
 * Copyright (C) 2000 Andreas Dilger
 * Copyright (C) 2000 Theodore Ts'o
 *
 * Parts of the code are based on fs/jfs/journal.c by Stephen C. Tweedie
 * Copyright (C) 1999 Red Hat Software
 *
 * This file may be redistributed under the terms of the
 * GNU General Public License version 2 or at your discretion
 * any later version.
 */

#include "config.h"
#ifdef HAVE_SYS_MOUNT_H
#include <sys/param.h>
#include <sys/mount.h>
#define MNT_FL (MS_MGC_VAL | MS_RDONLY)
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif

#define E2FSCK_INCLUDE_INLINE_FUNCS
#include "uuid/uuid.h"
#include "journal.h"

#ifdef CONFIG_JBD_DEBUG         /* Enabled by configure --enable-jfs-debug */
static int bh_count = 0;
#endif

#if EXT2_FLAT_INCLUDES
#include "blkid.h"
#else
#include "blkid/blkid.h"
#endif

/*
 * Define USE_INODE_IO to use the inode_io.c / fileio.c codepaths.
 * This creates a larger static binary, and a smaller binary using
 * shared libraries.  It's also probably slightly less CPU-efficient,
 * which is why it's not on by default.  But, it's a good way of
 * testing the functions in inode_io.c and fileio.c.
 */
#undef USE_INODE_IO

/* Checksumming functions */
static int ext2fs_journal_verify_csum_type(journal_t *j,
                                           journal_superblock_t *jsb)
{
        if (!journal_has_csum_v2or3(j))
                return 1;

        return jsb->s_checksum_type == JBD2_CRC32C_CHKSUM;
}

static __u32 ext2fs_journal_sb_csum(journal_superblock_t *jsb)
{
        __u32 crc, old_crc;

        old_crc = jsb->s_checksum;
        jsb->s_checksum = 0;
        crc = ext2fs_crc32c_le(~0, (unsigned char *)jsb,
                               sizeof(journal_superblock_t));
        jsb->s_checksum = old_crc;

        return crc;
}

static int ext2fs_journal_sb_csum_verify(journal_t *j,
                                         journal_superblock_t *jsb)
{
        __u32 provided, calculated;

        if (!journal_has_csum_v2or3(j))
                return 1;

        provided = ext2fs_be32_to_cpu(jsb->s_checksum);
        calculated = ext2fs_journal_sb_csum(jsb);

        return provided == calculated;
}

static errcode_t ext2fs_journal_sb_csum_set(journal_t *j,
                                            journal_superblock_t *jsb)
{
        __u32 crc;

        if (!journal_has_csum_v2or3(j))
                return 0;

        crc = ext2fs_journal_sb_csum(jsb);
        jsb->s_checksum = ext2fs_cpu_to_be32(crc);
        return 0;
}

/* Kernel compatibility functions for handling the journal.  These allow us
 * to use the recovery.c file virtually unchanged from the kernel, so we
 * don't have to do much to keep kernel and user recovery in sync.
 */
int journal_bmap(journal_t *journal, blk64_t block, unsigned long long *phys)
{
#ifdef USE_INODE_IO
        *phys = block;
        return 0;
#else
        struct inode    *inode = journal->j_inode;
        errcode_t       retval;
        blk64_t         pblk;

        if (!inode) {
                *phys = block;
                return 0;
        }

        retval = ext2fs_bmap2(inode->i_fs, inode->i_ino,
                              &inode->i_ext2, NULL, 0, block, 0, &pblk);
        *phys = pblk;
        return (int) retval;
#endif
}

struct buffer_head *getblk(kdev_t kdev, blk64_t blocknr, int blocksize)
{
        struct buffer_head *bh;
        int bufsize = sizeof(*bh) + kdev->k_fs->blocksize -
                sizeof(bh->b_data);
        errcode_t retval;

        retval = ext2fs_get_memzero(bufsize, &bh);
        if (retval)
                return NULL;

#ifdef CONFIG_JBD_DEBUG
        if (journal_enable_debug >= 3)
                bh_count++;
#endif
        jfs_debug(4, "getblk for block %llu (%d bytes)(total %d)\n",
                  (unsigned long long) blocknr, blocksize, bh_count);

        bh->b_fs = kdev->k_fs;
        if (kdev->k_dev == K_DEV_FS)
                bh->b_io = kdev->k_fs->io;
        else
                bh->b_io = kdev->k_fs->journal_io;
        bh->b_size = blocksize;
        bh->b_blocknr = blocknr;

        return bh;
}

int sync_blockdev(kdev_t kdev)
{
        io_channel      io;

        if (kdev->k_dev == K_DEV_FS)
                io = kdev->k_fs->io;
        else
                io = kdev->k_fs->journal_io;

        return io_channel_flush(io) ? EIO : 0;
}

void ll_rw_block(int rw, int nr, struct buffer_head *bhp[])
{
        errcode_t retval;
        struct buffer_head *bh;

        for (; nr > 0; --nr) {
                bh = *bhp++;
                if (rw == READ && !bh->b_uptodate) {
                        jfs_debug(3, "reading block %llu/%p\n",
                                  bh->b_blocknr, (void *) bh);
                        retval = io_channel_read_blk64(bh->b_io,
                                                     bh->b_blocknr,
                                                     1, bh->b_data);
                        if (retval) {
                                com_err(bh->b_fs->device_name, retval,
                                        "while reading block %llu\n",
                                        bh->b_blocknr);
                                bh->b_err = (int) retval;
                                continue;
                        }
                        bh->b_uptodate = 1;
                } else if (rw == WRITE && bh->b_dirty) {
                        jfs_debug(3, "writing block %llu/%p\n",
                                  bh->b_blocknr,
                                  (void *) bh);
                        retval = io_channel_write_blk64(bh->b_io,
                                                      bh->b_blocknr,
                                                      1, bh->b_data);
                        if (retval) {
                                com_err(bh->b_fs->device_name, retval,
                                        "while writing block %llu\n",
                                        bh->b_blocknr);
                                bh->b_err = (int) retval;
                                continue;
                        }
                        bh->b_dirty = 0;
                        bh->b_uptodate = 1;
                } else {
                        jfs_debug(3, "no-op %s for block %llu\n",
                                  rw == READ ? "read" : "write",
                                  bh->b_blocknr);
                }
        }
}

void mark_buffer_dirty(struct buffer_head *bh)
{
        bh->b_dirty = 1;
}

static void mark_buffer_clean(struct buffer_head *bh)
{
        bh->b_dirty = 0;
}

void brelse(struct buffer_head *bh)
{
        if (bh->b_dirty)
                ll_rw_block(WRITE, 1, &bh);
        jfs_debug(3, "freeing block %llu/%p (total %d)\n",
                  bh->b_blocknr, (void *) bh, --bh_count);
        ext2fs_free_mem(&bh);
}

int buffer_uptodate(struct buffer_head *bh)
{
        return bh->b_uptodate;
}

void mark_buffer_uptodate(struct buffer_head *bh, int val)
{
        bh->b_uptodate = val;
}

void wait_on_buffer(struct buffer_head *bh)
{
        if (!bh->b_uptodate)
                ll_rw_block(READ, 1, &bh);
}


static void ext2fs_clear_recover(ext2_filsys fs, int error)
{
        ext2fs_clear_feature_journal_needs_recovery(fs->super);

        /* if we had an error doing journal recovery, we need a full fsck */
        if (error)
                fs->super->s_state &= ~EXT2_VALID_FS;
        ext2fs_mark_super_dirty(fs);
}

/*
 * This is a helper function to check the validity of the journal.
 */
struct process_block_struct {
        e2_blkcnt_t     last_block;
};

static int process_journal_block(ext2_filsys fs,
                                 blk64_t        *block_nr,
                                 e2_blkcnt_t blockcnt,
                                 blk64_t ref_block EXT2FS_ATTR((unused)),
                                 int ref_offset EXT2FS_ATTR((unused)),
                                 void *priv_data)
{
        struct process_block_struct *p;
        blk64_t blk = *block_nr;

        p = (struct process_block_struct *) priv_data;

        if (!blk || blk < fs->super->s_first_data_block ||
            blk >= ext2fs_blocks_count(fs->super))
                return BLOCK_ABORT;

        if (blockcnt >= 0)
                p->last_block = blockcnt;
        return 0;
}

static errcode_t ext2fs_get_journal(ext2_filsys fs, journal_t **ret_journal)
{
        struct process_block_struct pb;
        struct ext2_super_block *sb = fs->super;
        struct ext2_super_block jsuper;
        struct buffer_head      *bh;
        struct inode            *j_inode = NULL;
        struct kdev_s           *dev_fs = NULL, *dev_journal;
        const char              *journal_name = 0;
        journal_t               *journal = NULL;
        errcode_t               retval = 0;
        io_manager              io_ptr = 0;
        unsigned long long      start = 0;
        int                     ext_journal = 0;
        int                     tried_backup_jnl = 0;

        retval = ext2fs_get_memzero(sizeof(journal_t), &journal);
        if (retval)
                return retval;

        retval = ext2fs_get_memzero(2 * sizeof(struct kdev_s), &dev_fs);
        if (retval)
                goto errout;
        dev_journal = dev_fs+1;

        dev_fs->k_fs = dev_journal->k_fs = fs;
        dev_fs->k_dev = K_DEV_FS;
        dev_journal->k_dev = K_DEV_JOURNAL;

        journal->j_dev = dev_journal;
        journal->j_fs_dev = dev_fs;
        journal->j_inode = NULL;
        journal->j_blocksize = fs->blocksize;

        if (uuid_is_null(sb->s_journal_uuid)) {
                if (!sb->s_journal_inum) {
                        retval = EXT2_ET_BAD_INODE_NUM;
                        goto errout;
                }
                retval = ext2fs_get_memzero(sizeof(*j_inode), &j_inode);
                if (retval)
                        goto errout;

                j_inode->i_fs = fs;
                j_inode->i_ino = sb->s_journal_inum;

                retval = ext2fs_read_inode(fs, sb->s_journal_inum,
                                           &j_inode->i_ext2);
                if (retval) {
try_backup_journal:
                        if (sb->s_jnl_backup_type != EXT3_JNL_BACKUP_BLOCKS ||
                            tried_backup_jnl)
                                goto errout;
                        memset(&j_inode->i_ext2, 0, sizeof(struct ext2_inode));
                        memcpy(&j_inode->i_ext2.i_block[0], sb->s_jnl_blocks,
                               EXT2_N_BLOCKS*4);
                        j_inode->i_ext2.i_size_high = sb->s_jnl_blocks[15];
                        j_inode->i_ext2.i_size = sb->s_jnl_blocks[16];
                        j_inode->i_ext2.i_links_count = 1;
                        j_inode->i_ext2.i_mode = LINUX_S_IFREG | 0600;
                        tried_backup_jnl++;
                }
                if (!j_inode->i_ext2.i_links_count ||
                    !LINUX_S_ISREG(j_inode->i_ext2.i_mode)) {
                        retval = EXT2_ET_NO_JOURNAL;
                        goto try_backup_journal;
                }
                if (EXT2_I_SIZE(&j_inode->i_ext2) / journal->j_blocksize <
                    JFS_MIN_JOURNAL_BLOCKS) {
                        retval = EXT2_ET_JOURNAL_TOO_SMALL;
                        goto try_backup_journal;
                }
                pb.last_block = -1;
                retval = ext2fs_block_iterate3(fs, j_inode->i_ino,
                                               BLOCK_FLAG_HOLE, 0,
                                               process_journal_block, &pb);
                if ((pb.last_block + 1) * fs->blocksize <
                    (int) EXT2_I_SIZE(&j_inode->i_ext2)) {
                        retval = EXT2_ET_JOURNAL_TOO_SMALL;
                        goto try_backup_journal;
                }
                if (tried_backup_jnl && (fs->flags & EXT2_FLAG_RW)) {
                        retval = ext2fs_write_inode(fs, sb->s_journal_inum,
                                                    &j_inode->i_ext2);
                        if (retval)
                                goto errout;
                }

                journal->j_maxlen = EXT2_I_SIZE(&j_inode->i_ext2) /
                        journal->j_blocksize;

#ifdef USE_INODE_IO
                retval = ext2fs_inode_io_intern2(fs, sb->s_journal_inum,
                                                 &j_inode->i_ext2,
                                                 &journal_name);
                if (retval)
                        goto errout;

                io_ptr = inode_io_manager;
#else
                journal->j_inode = j_inode;
                fs->journal_io = fs->io;
                retval = (errcode_t)journal_bmap(journal, 0, &start);
                if (retval)
                        goto errout;
#endif
        } else {
                ext_journal = 1;
                if (!fs->journal_name) {
                        char uuid[37];
                        blkid_cache blkid;

                        blkid_get_cache(&blkid, NULL);
                        uuid_unparse(sb->s_journal_uuid, uuid);
                        fs->journal_name = blkid_get_devname(blkid,
                                                              "UUID", uuid);
                        if (!fs->journal_name)
                                fs->journal_name = blkid_devno_to_devname(sb->s_journal_dev);
                        blkid_put_cache(blkid);
                }
                journal_name = fs->journal_name;

                if (!journal_name) {
                        retval = EXT2_ET_LOAD_EXT_JOURNAL;
                        goto errout;
                }

                jfs_debug(1, "Using journal file %s\n", journal_name);
                io_ptr = unix_io_manager;
        }

#if 0
        test_io_backing_manager = io_ptr;
        io_ptr = test_io_manager;
#endif
#ifndef USE_INODE_IO
        if (ext_journal)
#endif
        {
                retval = io_ptr->open(journal_name, fs->flags & EXT2_FLAG_RW,
                                      &fs->journal_io);
        }
        if (retval)
                goto errout;

        io_channel_set_blksize(fs->journal_io, fs->blocksize);

        if (ext_journal) {
                blk64_t maxlen;

                start = ext2fs_journal_sb_start(fs->blocksize) - 1;
                bh = getblk(dev_journal, start, fs->blocksize);
                if (!bh) {
                        retval = EXT2_ET_NO_MEMORY;
                        goto errout;
                }
                ll_rw_block(READ, 1, &bh);
                retval = bh->b_err;
                if (retval) {
                        brelse(bh);
                        goto errout;
                }
                memcpy(&jsuper, start ? bh->b_data :
                                bh->b_data + SUPERBLOCK_OFFSET,
                       sizeof(jsuper));
#ifdef WORDS_BIGENDIAN
                if (jsuper.s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
                        ext2fs_swap_super(&jsuper);
#endif
                if (jsuper.s_magic != EXT2_SUPER_MAGIC ||
                    !ext2fs_has_feature_journal_dev(&jsuper)) {
                        retval = EXT2_ET_LOAD_EXT_JOURNAL;
                        brelse(bh);
                        goto errout;
                }
                /* Make sure the journal UUID is correct */
                if (memcmp(jsuper.s_uuid, fs->super->s_journal_uuid,
                           sizeof(jsuper.s_uuid))) {
                        retval = EXT2_ET_LOAD_EXT_JOURNAL;
                        brelse(bh);
                        goto errout;
                }

                /* Check the superblock checksum */
                if (ext2fs_has_feature_metadata_csum(&jsuper)) {
                        struct struct_ext2_filsys fsx;
                        struct ext2_super_block superx;
                        void *p;

                        p = start ? bh->b_data : bh->b_data + SUPERBLOCK_OFFSET;
                        memcpy(&fsx, fs, sizeof(fsx));
                        memcpy(&superx, fs->super, sizeof(superx));
                        fsx.super = &superx;
                        ext2fs_set_feature_metadata_csum(fsx.super);
                        if (!ext2fs_superblock_csum_verify(&fsx, p)) {
                                retval = EXT2_ET_LOAD_EXT_JOURNAL;
                                brelse(bh);
                                goto errout;
                        }
                }
                brelse(bh);

                maxlen = ext2fs_blocks_count(&jsuper);
                journal->j_maxlen = (maxlen < 1ULL << 32) ? maxlen :
                                    (1ULL << 32) - 1;
                start++;
        }

        bh = getblk(dev_journal, start, journal->j_blocksize);
        if (!bh) {
                retval = EXT2_ET_NO_MEMORY;
                goto errout;
        }

        journal->j_sb_buffer = bh;
        journal->j_superblock = (journal_superblock_t *)bh->b_data;

#ifdef USE_INODE_IO
        if (j_inode)
                ext2fs_free_mem(&j_inode);
#endif

        *ret_journal = journal;
        return 0;

errout:
        if (dev_fs)
                ext2fs_free_mem(&dev_fs);
        if (j_inode)
                ext2fs_free_mem(&j_inode);
        if (journal)
                ext2fs_free_mem(&journal);
        return retval;
}

static errcode_t ext2fs_journal_fix_bad_inode(ext2_filsys fs)
{
        struct ext2_super_block *sb = fs->super;
        int recover = ext2fs_has_feature_journal_needs_recovery(fs->super);
        int has_journal = ext2fs_has_feature_journal(fs->super);

        if (has_journal || sb->s_journal_inum) {
                /* The journal inode is bogus, remove and force full fsck */
                return EXT2_ET_BAD_INODE_NUM;
        } else if (recover) {
                return EXT2_ET_UNSUPP_FEATURE;
        }
        return 0;
}

#define V1_SB_SIZE      0x0024
static void clear_v2_journal_fields(journal_t *journal)
{
        ext2_filsys fs = journal->j_dev->k_fs;

        memset(((char *) journal->j_superblock) + V1_SB_SIZE, 0,
               fs->blocksize-V1_SB_SIZE);
        mark_buffer_dirty(journal->j_sb_buffer);
}


static errcode_t ext2fs_journal_load(journal_t *journal)
{
        ext2_filsys fs = journal->j_dev->k_fs;
        journal_superblock_t *jsb;
        struct buffer_head *jbh = journal->j_sb_buffer;

        ll_rw_block(READ, 1, &jbh);
        if (jbh->b_err)
                return jbh->b_err;

        jsb = journal->j_superblock;
        /* If we don't even have JFS_MAGIC, we probably have a wrong inode */
        if (jsb->s_header.h_magic != htonl(JFS_MAGIC_NUMBER))
                return ext2fs_journal_fix_bad_inode(fs);

        switch (ntohl(jsb->s_header.h_blocktype)) {
        case JFS_SUPERBLOCK_V1:
                journal->j_format_version = 1;
                if (jsb->s_feature_compat ||
                    jsb->s_feature_incompat ||
                    jsb->s_feature_ro_compat ||
                    jsb->s_nr_users)
                        clear_v2_journal_fields(journal);
                break;

        case JFS_SUPERBLOCK_V2:
                journal->j_format_version = 2;
                if (ntohl(jsb->s_nr_users) > 1 &&
                    uuid_is_null(fs->super->s_journal_uuid))
                        clear_v2_journal_fields(journal);
                if (ntohl(jsb->s_nr_users) > 1)
                        return EXT2_ET_JOURNAL_UNSUPP_VERSION;
                break;

        /*
         * These should never appear in a journal super block, so if
         * they do, the journal is badly corrupted.
         */
        case JFS_DESCRIPTOR_BLOCK:
        case JFS_COMMIT_BLOCK:
        case JFS_REVOKE_BLOCK:
                return EXT2_ET_CORRUPT_SUPERBLOCK;

        /* If we don't understand the superblock major type, but there
         * is a magic number, then it is likely to be a new format we
         * just don't understand, so leave it alone. */
        default:
                return EXT2_ET_JOURNAL_UNSUPP_VERSION;
        }

        if (JFS_HAS_INCOMPAT_FEATURE(journal, ~JFS_KNOWN_INCOMPAT_FEATURES))
                return EXT2_ET_UNSUPP_FEATURE;

        if (JFS_HAS_RO_COMPAT_FEATURE(journal, ~JFS_KNOWN_ROCOMPAT_FEATURES))
                return EXT2_ET_RO_UNSUPP_FEATURE;

        /* Checksum v1-3 are mutually exclusive features. */
        if (jfs_has_feature_csum2(journal) && jfs_has_feature_csum3(journal))
                return EXT2_ET_CORRUPT_SUPERBLOCK;

        if (journal_has_csum_v2or3(journal) &&
            jfs_has_feature_checksum(journal))
                return EXT2_ET_CORRUPT_SUPERBLOCK;

        if (!ext2fs_journal_verify_csum_type(journal, jsb) ||
            !ext2fs_journal_sb_csum_verify(journal, jsb))
                return EXT2_ET_CORRUPT_SUPERBLOCK;

        if (journal_has_csum_v2or3(journal))
                journal->j_csum_seed = jbd2_chksum(journal, ~0, jsb->s_uuid,
                                                   sizeof(jsb->s_uuid));

        /* We have now checked whether we know enough about the journal
         * format to be able to proceed safely, so any other checks that
         * fail we should attempt to recover from. */
        if (jsb->s_blocksize != htonl(journal->j_blocksize))
                return EXT2_ET_CORRUPT_SUPERBLOCK;

        if (ntohl(jsb->s_maxlen) < journal->j_maxlen)
                journal->j_maxlen = ntohl(jsb->s_maxlen);
        else if (ntohl(jsb->s_maxlen) > journal->j_maxlen)
                return EXT2_ET_CORRUPT_SUPERBLOCK;

        journal->j_tail_sequence = ntohl(jsb->s_sequence);
        journal->j_transaction_sequence = journal->j_tail_sequence;
        journal->j_tail = ntohl(jsb->s_start);
        journal->j_first = ntohl(jsb->s_first);
        journal->j_last = ntohl(jsb->s_maxlen);

        return 0;
}

static void ext2fs_journal_release(ext2_filsys fs, journal_t *journal,
                                   int reset, int drop)
{
        journal_superblock_t *jsb;

        if (drop)
                mark_buffer_clean(journal->j_sb_buffer);
        else if (fs->flags & EXT2_FLAG_RW) {
                jsb = journal->j_superblock;
                jsb->s_sequence = htonl(journal->j_tail_sequence);
                if (reset)
                        jsb->s_start = 0; /* this marks the journal as empty */
                ext2fs_journal_sb_csum_set(journal, jsb);
                mark_buffer_dirty(journal->j_sb_buffer);
        }
        brelse(journal->j_sb_buffer);

        if (fs && fs->journal_io) {
                if (fs->io != fs->journal_io)
                        io_channel_close(fs->journal_io);
                fs->journal_io = NULL;
        }

#ifndef USE_INODE_IO
        if (journal->j_inode)
                ext2fs_free_mem(&journal->j_inode);
#endif
        if (journal->j_fs_dev)
                ext2fs_free_mem(&journal->j_fs_dev);
        ext2fs_free_mem(&journal);
}

/*
 * This function makes sure that the superblock fields regarding the
 * journal are consistent.
 */
static errcode_t ext2fs_check_ext3_journal(ext2_filsys fs)
{
        struct ext2_super_block *sb = fs->super;
        journal_t *journal;
        int recover = ext2fs_has_feature_journal_needs_recovery(fs->super);
        errcode_t retval;

        /* If we don't have any journal features, don't do anything more */
        if (!ext2fs_has_feature_journal(sb) &&
            !recover && sb->s_journal_inum == 0 && sb->s_journal_dev == 0 &&
            uuid_is_null(sb->s_journal_uuid))
                return 0;

        retval = ext2fs_get_journal(fs, &journal);
        if (retval)
                return retval;

        retval = ext2fs_journal_load(journal);
        if (retval)
                goto err;

        /*
         * We want to make the flags consistent here.  We will not leave with
         * needs_recovery set but has_journal clear.  We can't get in a loop
         * with -y, -n, or -p, only if a user isn't making up their mind.
         */
        if (!ext2fs_has_feature_journal(sb)) {
                retval = EXT2_ET_JOURNAL_FLAGS_WRONG;
                goto err;
        }

        if (ext2fs_has_feature_journal(sb) &&
            !ext2fs_has_feature_journal_needs_recovery(sb) &&
            journal->j_superblock->s_start != 0) {
                retval = EXT2_ET_JOURNAL_FLAGS_WRONG;
                goto err;
        }

        /*
         * If we don't need to do replay the journal, check to see if
         * the journal's errno is set; if so, we need to mark the file
         * system as being corrupt and clear the journal's s_errno.
         */
        if (!ext2fs_has_feature_journal_needs_recovery(sb) &&
            journal->j_superblock->s_errno) {
                fs->super->s_state |= EXT2_ERROR_FS;
                ext2fs_mark_super_dirty(fs);
                journal->j_superblock->s_errno = 0;
                ext2fs_journal_sb_csum_set(journal, journal->j_superblock);
                mark_buffer_dirty(journal->j_sb_buffer);
        }

err:
        ext2fs_journal_release(fs, journal, 0, retval ? 1 : 0);
        return retval;
}

static errcode_t recover_ext3_journal(ext2_filsys fs)
{
        journal_t *journal;
        errcode_t retval;

        journal_init_revoke_caches();
        retval = ext2fs_get_journal(fs, &journal);
        if (retval)
                return retval;

        retval = ext2fs_journal_load(journal);
        if (retval)
                goto errout;

        retval = journal_init_revoke(journal, 1024);
        if (retval)
                goto errout;

        retval = -journal_recover(journal);
        if (retval)
                goto errout;

        if (journal->j_failed_commit) {
                journal->j_superblock->s_errno = -EINVAL;
                mark_buffer_dirty(journal->j_sb_buffer);
        }

errout:
        journal_destroy_revoke(journal);
        journal_destroy_revoke_caches();
        ext2fs_journal_release(fs, journal, 1, 0);
        return retval;
}

errcode_t ext2fs_run_ext3_journal(ext2_filsys *fsp)
{
        ext2_filsys fs = *fsp;
        io_manager io_ptr = fs->io->manager;
        errcode_t       retval, recover_retval;
        io_stats        stats = 0;
        unsigned long long kbytes_written = 0;
        char *fsname;
        int fsflags;
        int fsblocksize;

        if (!(fs->flags & EXT2_FLAG_RW))
                return EXT2_ET_FILE_RO;

        if (fs->flags & EXT2_FLAG_DIRTY)
                ext2fs_flush(fs);       /* Force out any modifications */

        recover_retval = recover_ext3_journal(fs);

        /*
         * Reload the filesystem context to get up-to-date data from disk
         * because journal recovery will change the filesystem under us.
         */
        if (fs->super->s_kbytes_written &&
            fs->io->manager->get_stats)
                fs->io->manager->get_stats(fs->io, &stats);
        if (stats && stats->bytes_written)
                kbytes_written = stats->bytes_written >> 10;

        ext2fs_mmp_stop(fs);
        fsname = strdup(fs->device_name);
        fsflags = fs->flags;
        fsblocksize = fs->blocksize;
        ext2fs_free(fs);
        retval = ext2fs_open(fsname, fsflags,
                             0, fsblocksize, io_ptr,
                             fsp);
        free(fsname);
        if (retval)
                return retval;

        fs = *fsp;
        fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
        fs->super->s_kbytes_written += kbytes_written;

        /* Set the superblock flags */
        ext2fs_clear_recover(fs, recover_retval != 0);

        /*
         * Do one last sanity check, and propagate journal->s_errno to
         * the EXT2_ERROR_FS flag in the fs superblock if needed.
         */
        retval = ext2fs_check_ext3_journal(fs);
        return retval ? retval : recover_retval;
}

errcode_t ext2fs_open_journal(ext2_filsys fs, journal_t **j)
{
        journal_t *journal;
        errcode_t retval;

        journal_init_revoke_caches();
        retval = ext2fs_get_journal(fs, &journal);
        if (retval)
                return retval;

        retval = ext2fs_journal_load(journal);
        if (retval)
                goto errout;

        retval = journal_init_revoke(journal, 1024);
        if (retval)
                goto errout;

        if (journal->j_failed_commit) {
                journal->j_superblock->s_errno = -EINVAL;
                mark_buffer_dirty(journal->j_sb_buffer);
        }

        *j = journal;
        return 0;

errout:
        journal_destroy_revoke(journal);
        journal_destroy_revoke_caches();
        ext2fs_journal_release(fs, journal, 1, 0);
        return retval;
}

errcode_t ext2fs_close_journal(ext2_filsys fs, journal_t **j)
{
        journal_t *journal = *j;

        journal_destroy_revoke(journal);
        journal_destroy_revoke_caches();
        ext2fs_journal_release(fs, journal, 0, 0);
        *j = NULL;

        return 0;
}

void jbd2_commit_block_csum_set(journal_t *j, struct buffer_head *bh)
{
        struct commit_header *h;
        __u32 csum;

        if (!journal_has_csum_v2or3(j))
                return;

        h = (struct commit_header *)(bh->b_data);
        h->h_chksum_type = 0;
        h->h_chksum_size = 0;
        h->h_chksum[0] = 0;
        csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize);
        h->h_chksum[0] = ext2fs_cpu_to_be32(csum);
}

void jbd2_revoke_csum_set(journal_t *j, struct buffer_head *bh)
{
        struct journal_revoke_tail *tail;
        __u32 csum;

        if (!journal_has_csum_v2or3(j))
                return;

        tail = (struct journal_revoke_tail *)(bh->b_data + j->j_blocksize -
                        sizeof(struct journal_revoke_tail));
        tail->r_checksum = 0;
        csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize);
        tail->r_checksum = ext2fs_cpu_to_be32(csum);
}

void jbd2_descr_block_csum_set(journal_t *j, struct buffer_head *bh)
{
        struct journal_block_tail *tail;
        __u32 csum;

        if (!journal_has_csum_v2or3(j))
                return;

        tail = (struct journal_block_tail *)(bh->b_data + j->j_blocksize -
                        sizeof(struct journal_block_tail));
        tail->t_checksum = 0;
        csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize);
        tail->t_checksum = ext2fs_cpu_to_be32(csum);
}

void jbd2_block_tag_csum_set(journal_t *j, journal_block_tag_t *tag,
                             struct buffer_head *bh, __u32 sequence)
{
        journal_block_tag3_t *tag3 = (journal_block_tag3_t *)tag;
        __u32 csum32;
        __be32 seq;

        if (!journal_has_csum_v2or3(j))
                return;

        seq = ext2fs_cpu_to_be32(sequence);
        csum32 = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&seq, sizeof(seq));
        csum32 = jbd2_chksum(j, csum32, bh->b_data, bh->b_size);

        if (jfs_has_feature_csum3(j))
                tag3->t_checksum = ext2fs_cpu_to_be32(csum32);
        else
                tag->t_checksum = ext2fs_cpu_to_be16(csum32);
}