Esempio n. 1
0
uint32_t HELPER(nsa)(uint32_t v)
{
    if (v & 0x80000000) {
        v = ~v;
    }
    return v ? clz32(v) - 1 : 31;
}
Esempio n. 2
0
EncodedJSValue JSC_HOST_CALL mathProtoFuncClz32(ExecState* exec)
{
    VM& vm = exec->vm();
    auto scope = DECLARE_THROW_SCOPE(vm);
    uint32_t value = exec->argument(0).toUInt32(exec);
    RETURN_IF_EXCEPTION(scope, encodedJSValue());
    return JSValue::encode(JSValue(clz32(value)));
}
Esempio n. 3
0
/*
 * Determine the level for a skiplist node by choosing a level N with
 * probability P(N) = 1/(2**(N+1)) in the range 0..32, with  the returned
 * level clamped at the current skiplist height plus 1.
 */
static int
skiplist_determine_level(struct skiplist *sl)
{
    int lvl;

    lvl = clz32(random_uint32());

    return MIN(lvl, sl->level + 1);
}
Esempio n. 4
0
/*
 * ACPI 6.2 Errata A: 5.2.25.9 NVDIMM Platform Capabilities Structure
 */
static void
nvdimm_build_structure_caps(GArray *structures, uint32_t capabilities)
{
    NvdimmNfitPlatformCaps *nfit_caps;

    nfit_caps = acpi_data_push(structures, sizeof(*nfit_caps));

    nfit_caps->type = cpu_to_le16(7 /* NVDIMM Platform Capabilities */);
    nfit_caps->length = cpu_to_le16(sizeof(*nfit_caps));
    nfit_caps->highest_cap = 31 - clz32(capabilities);
    nfit_caps->capabilities = cpu_to_le32(capabilities);
}
Esempio n. 5
0
int qemu_fls(int i)
{
    return 32 - clz32(i);
}
Esempio n. 6
0
uint32_t HELPER(clz)(uint32_t x)
{
    return clz32(x);
}
Esempio n. 7
0
/* Find first bit starting from msb */
static int apic_fls_bit(uint32_t value)
{
    return 31 - clz32(value);
}
Esempio n. 8
0
uint32_t helper_clz(uint32_t t0)
{
    return clz32(t0);
}
Esempio n. 9
0
uint32_t HELPER(clz_i32)(uint32_t arg, uint32_t zero_val)
{
    return arg ? clz32(arg) : zero_val;
}
Esempio n. 10
0
uint32_t HELPER(nsau)(uint32_t v)
{
    return v ? clz32(v) : 32;
}
Esempio n. 11
0
/* Metadata initial parser
 *
 * This loads all the metadata entry fields.  This may cause additional
 * fields to be processed (e.g. parent locator, etc..).
 *
 * There are 5 Metadata items that are always required:
 *      - File Parameters (block size, has a parent)
 *      - Virtual Disk Size (size, in bytes, of the virtual drive)
 *      - Page 83 Data (scsi page 83 guid)
 *      - Logical Sector Size (logical sector size in bytes, either 512 or
 *                             4096.  We only support 512 currently)
 *      - Physical Sector Size (512 or 4096)
 *
 * Also, if the File Parameters indicate this is a differencing file,
 * we must also look for the Parent Locator metadata item.
 */
static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s)
{
    int ret = 0;
    uint8_t *buffer;
    int offset = 0;
    uint32_t i = 0;
    VHDXMetadataTableEntry md_entry;

    buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE);

    ret = bdrv_pread(bs->file, s->metadata_rt.file_offset, buffer,
                     VHDX_METADATA_TABLE_MAX_SIZE);
    if (ret < 0) {
        goto exit;
    }
    memcpy(&s->metadata_hdr, buffer, sizeof(s->metadata_hdr));
    offset += sizeof(s->metadata_hdr);

    le64_to_cpus(&s->metadata_hdr.signature);
    le16_to_cpus(&s->metadata_hdr.reserved);
    le16_to_cpus(&s->metadata_hdr.entry_count);

    if (memcmp(&s->metadata_hdr.signature, "metadata", 8)) {
        ret = -EINVAL;
        goto exit;
    }

    s->metadata_entries.present = 0;

    if ((s->metadata_hdr.entry_count * sizeof(md_entry)) >
        (VHDX_METADATA_TABLE_MAX_SIZE - offset)) {
        ret = -EINVAL;
        goto exit;
    }

    for (i = 0; i < s->metadata_hdr.entry_count; i++) {
        memcpy(&md_entry, buffer + offset, sizeof(md_entry));
        offset += sizeof(md_entry);

        leguid_to_cpus(&md_entry.item_id);
        le32_to_cpus(&md_entry.offset);
        le32_to_cpus(&md_entry.length);
        le32_to_cpus(&md_entry.data_bits);
        le32_to_cpus(&md_entry.reserved2);

        if (guid_eq(md_entry.item_id, file_param_guid)) {
            if (s->metadata_entries.present & META_FILE_PARAMETER_PRESENT) {
                ret = -EINVAL;
                goto exit;
            }
            s->metadata_entries.file_parameters_entry = md_entry;
            s->metadata_entries.present |= META_FILE_PARAMETER_PRESENT;
            continue;
        }

        if (guid_eq(md_entry.item_id, virtual_size_guid)) {
            if (s->metadata_entries.present & META_VIRTUAL_DISK_SIZE_PRESENT) {
                ret = -EINVAL;
                goto exit;
            }
            s->metadata_entries.virtual_disk_size_entry = md_entry;
            s->metadata_entries.present |= META_VIRTUAL_DISK_SIZE_PRESENT;
            continue;
        }

        if (guid_eq(md_entry.item_id, page83_guid)) {
            if (s->metadata_entries.present & META_PAGE_83_PRESENT) {
                ret = -EINVAL;
                goto exit;
            }
            s->metadata_entries.page83_data_entry = md_entry;
            s->metadata_entries.present |= META_PAGE_83_PRESENT;
            continue;
        }

        if (guid_eq(md_entry.item_id, logical_sector_guid)) {
            if (s->metadata_entries.present &
                META_LOGICAL_SECTOR_SIZE_PRESENT) {
                ret = -EINVAL;
                goto exit;
            }
            s->metadata_entries.logical_sector_size_entry = md_entry;
            s->metadata_entries.present |= META_LOGICAL_SECTOR_SIZE_PRESENT;
            continue;
        }

        if (guid_eq(md_entry.item_id, phys_sector_guid)) {
            if (s->metadata_entries.present & META_PHYS_SECTOR_SIZE_PRESENT) {
                ret = -EINVAL;
                goto exit;
            }
            s->metadata_entries.phys_sector_size_entry = md_entry;
            s->metadata_entries.present |= META_PHYS_SECTOR_SIZE_PRESENT;
            continue;
        }

        if (guid_eq(md_entry.item_id, parent_locator_guid)) {
            if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) {
                ret = -EINVAL;
                goto exit;
            }
            s->metadata_entries.parent_locator_entry = md_entry;
            s->metadata_entries.present |= META_PARENT_LOCATOR_PRESENT;
            continue;
        }

        if (md_entry.data_bits & VHDX_META_FLAGS_IS_REQUIRED) {
            /* cannot read vhdx file - required region table entry that
             * we do not understand.  per spec, we must fail to open */
            ret = -ENOTSUP;
            goto exit;
        }
    }

    if (s->metadata_entries.present != META_ALL_PRESENT) {
        ret = -ENOTSUP;
        goto exit;
    }

    ret = bdrv_pread(bs->file,
                     s->metadata_entries.file_parameters_entry.offset
                                         + s->metadata_rt.file_offset,
                     &s->params,
                     sizeof(s->params));

    if (ret < 0) {
        goto exit;
    }

    le32_to_cpus(&s->params.block_size);
    le32_to_cpus(&s->params.data_bits);


    /* We now have the file parameters, so we can tell if this is a
     * differencing file (i.e.. has_parent), is dynamic or fixed
     * sized (leave_blocks_allocated), and the block size */

    /* The parent locator required iff the file parameters has_parent set */
    if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) {
        if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) {
            /* TODO: parse  parent locator fields */
            ret = -ENOTSUP; /* temp, until differencing files are supported */
            goto exit;
        } else {
            /* if has_parent is set, but there is not parent locator present,
             * then that is an invalid combination */
            ret = -EINVAL;
            goto exit;
        }
    }

    /* determine virtual disk size, logical sector size,
     * and phys sector size */

    ret = bdrv_pread(bs->file,
                     s->metadata_entries.virtual_disk_size_entry.offset
                                           + s->metadata_rt.file_offset,
                     &s->virtual_disk_size,
                     sizeof(uint64_t));
    if (ret < 0) {
        goto exit;
    }
    ret = bdrv_pread(bs->file,
                     s->metadata_entries.logical_sector_size_entry.offset
                                             + s->metadata_rt.file_offset,
                     &s->logical_sector_size,
                     sizeof(uint32_t));
    if (ret < 0) {
        goto exit;
    }
    ret = bdrv_pread(bs->file,
                     s->metadata_entries.phys_sector_size_entry.offset
                                          + s->metadata_rt.file_offset,
                     &s->physical_sector_size,
                     sizeof(uint32_t));
    if (ret < 0) {
        goto exit;
    }

    le64_to_cpus(&s->virtual_disk_size);
    le32_to_cpus(&s->logical_sector_size);
    le32_to_cpus(&s->physical_sector_size);

    if (s->logical_sector_size == 0 || s->params.block_size == 0) {
        ret = -EINVAL;
        goto exit;
    }

    /* both block_size and sector_size are guaranteed powers of 2 */
    s->sectors_per_block = s->params.block_size / s->logical_sector_size;
    s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) *
                     (uint64_t)s->logical_sector_size /
                     (uint64_t)s->params.block_size;

    /* These values are ones we will want to use for division / multiplication
     * later on, and they are all guaranteed (per the spec) to be powers of 2,
     * so we can take advantage of that for shift operations during
     * reads/writes */
    if (s->logical_sector_size & (s->logical_sector_size - 1)) {
        ret = -EINVAL;
        goto exit;
    }
    if (s->sectors_per_block & (s->sectors_per_block - 1)) {
        ret = -EINVAL;
        goto exit;
    }
    if (s->chunk_ratio & (s->chunk_ratio - 1)) {
        ret = -EINVAL;
        goto exit;
    }
    s->block_size = s->params.block_size;
    if (s->block_size & (s->block_size - 1)) {
        ret = -EINVAL;
        goto exit;
    }

    s->logical_sector_size_bits = 31 - clz32(s->logical_sector_size);
    s->sectors_per_block_bits =   31 - clz32(s->sectors_per_block);
    s->chunk_ratio_bits =         63 - clz64(s->chunk_ratio);
    s->block_size_bits =          31 - clz32(s->block_size);

    ret = 0;

exit:
    qemu_vfree(buffer);
    return ret;
}