Archipelago » qemu

/*

 * Block driver for the QCOW format

 * Copyright (c) 2004-2006 Fabrice Bellard

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)

{

    const QCowHeader *cow_header = (const void *)buf;

    if (buf_size >= sizeof(QCowHeader) &&

        be32_to_cpu(cow_header->magic) == QCOW_MAGIC &&

        return 100;

    else

        return 0;

    be64_to_cpus(&header.size);

    be32_to_cpus(&header.crypt_method);

    be64_to_cpus(&header.l1_table_offset);

    if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION)

        goto fail;

    if (header.size <= 1 || header.cluster_bits < 9)

    s->l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));

    if (!s->l1_table)

        goto fail;

        s->l1_size * sizeof(uint64_t))

        goto fail;

    for(i = 0;i < s->l1_size; i++) {

    if (!s->cluster_data)

        goto fail;

    s->cluster_cache_offset = -1;

    /* read the backing file name */

    if (header.backing_file_offset != 0) {

        len = header.backing_file_size;

    BDRVQcowState *s = bs->opaque;

    uint8_t keybuf[16];

    int len, i;

    memset(keybuf, 0, 16);

    len = strlen(key);

    if (len > 16)

    for(i = 0; i < nb_sectors; i++) {

        ivec.ll[0] = cpu_to_le64(sector_num);

        ivec.ll[1] = 0;

                        ivec.b, enc);

        sector_num++;

        in_buf += 512;

 *

 * 2 to allocate a compressed cluster of size

 * 'compressed_size'. 'compressed_size' must be > 0 and <

 *

 * return 0 if not allocated.

 */

    uint64_t l2_offset, *l2_table, cluster_offset, tmp;

    uint32_t min_count;

    int new_l2_table;

    l1_index = offset >> (s->l2_bits + s->cluster_bits);

    l2_offset = s->l1_table[l1_index];

    new_l2_table = 0;

        /* update the L1 entry */

        s->l1_table[l1_index] = l2_offset;

        tmp = cpu_to_be64(l2_offset);

                        &tmp, sizeof(tmp)) != sizeof(tmp))

            return 0;

        new_l2_table = 1;

            s->l2_size * sizeof(uint64_t))

            return 0;

    } else {

            s->l2_size * sizeof(uint64_t))

            return 0;

    }

 found:

    l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);

    cluster_offset = be64_to_cpu(l2_table[l2_index]);

        ((cluster_offset & QCOW_OFLAG_COMPRESSED) && allocate == 1)) {

        if (!allocate)

            return 0;

            if (decompress_cluster(s, cluster_offset) < 0)

                return 0;

            cluster_offset = bdrv_getlength(s->hd);

                ~(s->cluster_size - 1);

            /* write the cluster content */

                s->cluster_size)

                return -1;

        } else {

            cluster_offset = bdrv_getlength(s->hd);

            if (allocate == 1) {

                /* round to cluster size */

                    ~(s->cluster_size - 1);

                bdrv_truncate(s->hd, cluster_offset + s->cluster_size);

                /* if encrypted, we must initialize the cluster

                   content which won't be written */

                    (n_end - n_start) < s->cluster_sectors) {

                    uint64_t start_sect;

                    start_sect = (offset & ~(s->cluster_size - 1)) >> 9;

                    memset(s->cluster_data + 512, 0x00, 512);

                    for(i = 0; i < s->cluster_sectors; i++) {

                        if (i < n_start || i >= n_end) {

                                            s->cluster_data + 512, 1, 1,

                                            &s->aes_encrypt_key);

                                            s->cluster_data, 512) != 512)

                                return -1;

                        }

                    }

                }

            } else {

                    (uint64_t)compressed_size << (63 - s->cluster_bits);

            }

        }

        /* update L2 table */

        tmp = cpu_to_be64(cluster_offset);

        l2_table[l2_index] = tmp;

                        l2_offset + l2_index * sizeof(tmp), &tmp, sizeof(tmp)) != sizeof(tmp))

            return 0;

    }

    return cluster_offset;

}

                             int nb_sectors, int *pnum)

{

    BDRVQcowState *s = bs->opaque;

    inflateEnd(strm);

    return 0;

}

static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)

{

    int ret, csize;

        csize = cluster_offset >> (63 - s->cluster_bits);

        csize &= (s->cluster_size - 1);

        ret = bdrv_pread(s->hd, coffset, s->cluster_data, csize);

            return -1;

        if (decompress_buffer(s->cluster_cache, s->cluster_size,

                              s->cluster_data, csize) < 0) {

#if 0

                     uint8_t *buf, int nb_sectors)

{

    BDRVQcowState *s = bs->opaque;

    int ret, index_in_cluster, n;

    uint64_t cluster_offset;

    while (nb_sectors > 0) {

        cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0);

        index_in_cluster = sector_num & (s->cluster_sectors - 1);

            memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);

        } else {

            ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);

                return -1;

            if (s->crypt_method) {

                                &s->aes_decrypt_key);

            }

        }

}

#endif

                     const uint8_t *buf, int nb_sectors)

{

    BDRVQcowState *s = bs->opaque;

    int ret, index_in_cluster, n;

    uint64_t cluster_offset;

    while (nb_sectors > 0) {

        index_in_cluster = sector_num & (s->cluster_sectors - 1);

        n = s->cluster_sectors - index_in_cluster;

        if (n > nb_sectors)

            n = nb_sectors;

                                            index_in_cluster + n);

        if (!cluster_offset)

            return -1;

        if (s->crypt_method) {

            encrypt_sectors(s, sector_num, s->cluster_data, buf, n, 1,

                            &s->aes_encrypt_key);

                              s->cluster_data, n * 512);

        } else {

            ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);

        }

            return -1;

        nb_sectors -= n;

        sector_num += n;

    int nb_sectors;

    int n;

    uint64_t cluster_offset;

    BlockDriverAIOCB *hd_aiocb;

} QCowAIOCB;

        /* nothing to do */

    } else {

        if (s->crypt_method) {

                            &s->aes_decrypt_key);

        }

    }

        qemu_aio_release(acb);

        return;

    }

    /* prepare next AIO request */

                                             0, 0, 0, 0);

    index_in_cluster = acb->sector_num & (s->cluster_sectors - 1);

    acb->n = s->cluster_sectors - index_in_cluster;

        /* add AIO support for compressed blocks ? */

        if (decompress_cluster(s, acb->cluster_offset) < 0)

            goto fail;

               s->cluster_cache + index_in_cluster * 512, 512 * acb->n);

        goto redo;

    } else {

            goto fail;

        }

        acb->hd_aiocb = bdrv_aio_read(s->hd,

                            acb->buf, acb->n, qcow_aio_read_cb, acb);

        if (acb->hd_aiocb == NULL)

            goto fail;

    acb->buf = buf;

    acb->nb_sectors = nb_sectors;

    acb->n = 0;

    qcow_aio_read_cb(acb, 0);

    return &acb->common;

        qemu_aio_release(acb);

        return;

    }

    index_in_cluster = acb->sector_num & (s->cluster_sectors - 1);

    acb->n = s->cluster_sectors - index_in_cluster;

    if (acb->n > acb->nb_sectors)

        acb->n = acb->nb_sectors;

                                        index_in_cluster + acb->n);

    if (!cluster_offset || (cluster_offset & 511) != 0) {

        ret = -EIO;

                goto fail;

            }

        }

                        acb->n, 1, &s->aes_encrypt_key);

        src_buf = acb->cluster_data;

    } else {

        src_buf = acb->buf;

    }

    acb->hd_aiocb = bdrv_aio_write(s->hd,

                                   qcow_aio_write_cb, acb);

    if (acb->hd_aiocb == NULL)

        goto fail;

{

    BDRVQcowState *s = bs->opaque;

    QCowAIOCB *acb;

    s->cluster_cache_offset = -1; /* disable compressed cache */

    acb = qemu_aio_get(bs, cb, opaque);

    acb->buf = (uint8_t *)buf;

    acb->nb_sectors = nb_sectors;

    acb->n = 0;

    qcow_aio_write_cb(acb, 0);

    return &acb->common;

}

    } else {

        header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);

    }

    /* write all the data */

    write(fd, &header, sizeof(header));

    if (backing_file) {

/* XXX: put compressed sectors first, then all the cluster aligned

   tables to avoid losing bytes in alignment */

                                 const uint8_t *buf, int nb_sectors)

{

    BDRVQcowState *s = bs->opaque;

    /* best compression, small window, no zlib header */

    memset(&strm, 0, sizeof(strm));

    ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION,

                       9, Z_DEFAULT_STRATEGY);

    if (ret != 0) {

        qemu_free(out_buf);

        /* could not compress: write normal cluster */

        qcow_write(bs, sector_num, buf, s->cluster_sectors);

    } else {

                                            out_len, 0, 0);

        cluster_offset &= s->cluster_offset_mask;

        if (bdrv_pwrite(s->hd, cluster_offset, out_buf, out_len) != out_len) {

            return -1;

        }

    }

    qemu_free(out_buf);

    return 0;

}