Archipelago » qemu

/*

 * QEMU disk image utility

 *

 * Copyright (c) 2003-2008 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

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "qapi-visit.h"

#include "qapi/qmp-output-visitor.h"

#include "qapi/qmp/qjson.h"

#include "qemu-common.h"

#include "qemu/option.h"

#include "qemu/error-report.h"

#include "qemu/osdep.h"

#include "sysemu/sysemu.h"

#include "block/block_int.h"

#include <getopt.h>

#include <stdio.h>

#include <stdarg.h>

#ifdef _WIN32

#include <windows.h>

#endif

typedef struct img_cmd_t {

    const char *name;

    int (*handler)(int argc, char **argv);

} img_cmd_t;

enum {

    OPTION_OUTPUT = 256,

    OPTION_BACKING_CHAIN = 257,

};

typedef enum OutputFormat {

    OFORMAT_JSON,

    OFORMAT_HUMAN,

} OutputFormat;

/* Default to cache=writeback as data integrity is not important for qemu-tcg. */

#define BDRV_O_FLAGS BDRV_O_CACHE_WB

#define BDRV_DEFAULT_CACHE "writeback"

static void format_print(void *opaque, const char *name)

{

    printf(" %s", name);

}

/* Please keep in synch with qemu-img.texi */

static void help(void)

{

    const char *help_msg =

           "qemu-img version " QEMU_VERSION ", Copyright (c) 2004-2008 Fabrice Bellard\n"

           "usage: qemu-img command [command options]\n"

           "QEMU disk image utility\n"

           "\n"

           "Command syntax:\n"

#define DEF(option, callback, arg_string)        \

           "  " arg_string "\n"

#include "qemu-img-cmds.h"

#undef DEF

#undef GEN_DOCS

           "\n"

           "Command parameters:\n"

           "  'filename' is a disk image filename\n"

           "  'fmt' is the disk image format. It is guessed automatically in most cases\n"

           "  'cache' is the cache mode used to write the output disk image, the valid\n"

           "    options are: 'none', 'writeback' (default, except for convert), 'writethrough',\n"

           "    'directsync' and 'unsafe' (default for convert)\n"

           "  'size' is the disk image size in bytes. Optional suffixes\n"

           "    'k' or 'K' (kilobyte, 1024), 'M' (megabyte, 1024k), 'G' (gigabyte, 1024M)\n"

           "    and T (terabyte, 1024G) are supported. 'b' is ignored.\n"

           "  'output_filename' is the destination disk image filename\n"

           "  'output_fmt' is the destination format\n"

           "  'options' is a comma separated list of format specific options in a\n"

           "    name=value format. Use -o ? for an overview of the options supported by the\n"

           "    used format\n"

           "  '-c' indicates that target image must be compressed (qcow format only)\n"

           "  '-u' enables unsafe rebasing. It is assumed that old and new backing file\n"

           "       match exactly. The image doesn't need a working backing file before\n"

           "       rebasing in this case (useful for renaming the backing file)\n"

           "  '-h' with or without a command shows this help and lists the supported formats\n"

           "  '-p' show progress of command (only certain commands)\n"

           "  '-q' use Quiet mode - do not print any output (except errors)\n"

           "  '-S' indicates the consecutive number of bytes that must contain only zeros\n"

           "       for qemu-img to create a sparse image during conversion\n"

           "  '--output' takes the format in which the output must be done (human or json)\n"

           "\n"

           "Parameters to check subcommand:\n"

           "  '-r' tries to repair any inconsistencies that are found during the check.\n"

           "       '-r leaks' repairs only cluster leaks, whereas '-r all' fixes all\n"

           "       kinds of errors, with a higher risk of choosing the wrong fix or\n"

           "       hiding corruption that has already occurred.\n"

           "\n"

           "Parameters to snapshot subcommand:\n"

           "  'snapshot' is the name of the snapshot to create, apply or delete\n"

           "  '-a' applies a snapshot (revert disk to saved state)\n"

           "  '-c' creates a snapshot\n"

           "  '-d' deletes a snapshot\n"

           "  '-l' lists all snapshots in the given image\n"

           "\n"

           "Parameters to compare subcommand:\n"

           "  '-f' first image format\n"

           "  '-F' second image format\n"

           "  '-s' run in Strict mode - fail on different image size or sector allocation\n";

    printf("%s\nSupported formats:", help_msg);

    bdrv_iterate_format(format_print, NULL);

    printf("\n");

    exit(1);

}

static int qprintf(bool quiet, const char *fmt, ...)

{

    int ret = 0;

    if (!quiet) {

        va_list args;

        va_start(args, fmt);

        ret = vprintf(fmt, args);

        va_end(args);

    }

    return ret;

}

#if defined(WIN32)

/* XXX: put correct support for win32 */

static int read_password(char *buf, int buf_size)

{

    int c, i;

    printf("Password: ");

    fflush(stdout);

    i = 0;

    for(;;) {

        c = getchar();

        if (c == '\n')

            break;

        if (i < (buf_size - 1))

            buf[i++] = c;

    }

    buf[i] = '\0';

    return 0;

}

#else

#include <termios.h>

static struct termios oldtty;

static void term_exit(void)

{

    tcsetattr (0, TCSANOW, &oldtty);

}

static void term_init(void)

{

    struct termios tty;

    tcgetattr (0, &tty);

    oldtty = tty;

    tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP

                          |INLCR|IGNCR|ICRNL|IXON);

    tty.c_oflag |= OPOST;

    tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);

    tty.c_cflag &= ~(CSIZE|PARENB);

    tty.c_cflag |= CS8;

    tty.c_cc[VMIN] = 1;

    tty.c_cc[VTIME] = 0;

    tcsetattr (0, TCSANOW, &tty);

    atexit(term_exit);

}

static int read_password(char *buf, int buf_size)

{

    uint8_t ch;

    int i, ret;

    printf("password: ");

    fflush(stdout);

    term_init();

    i = 0;

    for(;;) {

        ret = read(0, &ch, 1);

        if (ret == -1) {

            if (errno == EAGAIN || errno == EINTR) {

                continue;

            } else {

                ret = -1;

                break;

            }

        } else if (ret == 0) {

            ret = -1;

            break;

        } else {

            if (ch == '\r') {

                ret = 0;

                break;

            }

            if (i < (buf_size - 1))

                buf[i++] = ch;

        }

    }

    term_exit();

    buf[i] = '\0';

    printf("\n");

    return ret;

}

#endif

static int print_block_option_help(const char *filename, const char *fmt)

{

    BlockDriver *drv, *proto_drv;

    QEMUOptionParameter *create_options = NULL;

    /* Find driver and parse its options */

    drv = bdrv_find_format(fmt);

    if (!drv) {

        error_report("Unknown file format '%s'", fmt);

        return 1;

    }

    proto_drv = bdrv_find_protocol(filename);

    if (!proto_drv) {

        error_report("Unknown protocol '%s'", filename);

        return 1;

    }

    create_options = append_option_parameters(create_options,

                                              drv->create_options);

    create_options = append_option_parameters(create_options,

                                              proto_drv->create_options);

    print_option_help(create_options);

    free_option_parameters(create_options);

    return 0;

}

static BlockDriverState *bdrv_new_open(const char *filename,

                                       const char *fmt,

                                       int flags,

                                       bool require_io,

                                       bool quiet)

{

    BlockDriverState *bs;

    BlockDriver *drv;

    char password[256];

    int ret;

    bs = bdrv_new("image");

    if (fmt) {

        drv = bdrv_find_format(fmt);

        if (!drv) {

            error_report("Unknown file format '%s'", fmt);

            goto fail;

        }

    } else {

        drv = NULL;

    }

    ret = bdrv_open(bs, filename, NULL, flags, drv);

    if (ret < 0) {

        error_report("Could not open '%s': %s", filename, strerror(-ret));

        goto fail;

    }

    if (bdrv_is_encrypted(bs) && require_io) {

        qprintf(quiet, "Disk image '%s' is encrypted.\n", filename);

        if (read_password(password, sizeof(password)) < 0) {

            error_report("No password given");

            goto fail;

        }

        if (bdrv_set_key(bs, password) < 0) {

            error_report("invalid password");

            goto fail;

        }

    }

    return bs;

fail:

    if (bs) {

        bdrv_delete(bs);

    }

    return NULL;

}

static int add_old_style_options(const char *fmt, QEMUOptionParameter *list,

                                 const char *base_filename,

                                 const char *base_fmt)

{

    if (base_filename) {

        if (set_option_parameter(list, BLOCK_OPT_BACKING_FILE, base_filename)) {

            error_report("Backing file not supported for file format '%s'",

                         fmt);

            return -1;

        }

    }

    if (base_fmt) {

        if (set_option_parameter(list, BLOCK_OPT_BACKING_FMT, base_fmt)) {

            error_report("Backing file format not supported for file "

                         "format '%s'", fmt);

            return -1;

        }

    }

    return 0;

}

static int img_create(int argc, char **argv)

{

    int c;

    uint64_t img_size = -1;

    const char *fmt = "raw";

    const char *base_fmt = NULL;

    const char *filename;

    const char *base_filename = NULL;

    char *options = NULL;

    Error *local_err = NULL;

    bool quiet = false;

    for(;;) {

        c = getopt(argc, argv, "F:b:f:he6o:q");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'F':

            base_fmt = optarg;

            break;

        case 'b':

            base_filename = optarg;

            break;

        case 'f':

            fmt = optarg;

            break;

        case 'e':

            error_report("option -e is deprecated, please use \'-o "

                  "encryption\' instead!");

            return 1;

        case '6':

            error_report("option -6 is deprecated, please use \'-o "

                  "compat6\' instead!");

            return 1;

        case 'o':

            options = optarg;

            break;

        case 'q':

            quiet = true;

            break;

        }

    }

    /* Get the filename */

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    /* Get image size, if specified */

    if (optind < argc) {

        int64_t sval;

        char *end;

        sval = strtosz_suffix(argv[optind++], &end, STRTOSZ_DEFSUFFIX_B);

        if (sval < 0 || *end) {

            if (sval == -ERANGE) {

                error_report("Image size must be less than 8 EiB!");

            } else {

                error_report("Invalid image size specified! You may use k, M, "

                      "G or T suffixes for ");

                error_report("kilobytes, megabytes, gigabytes and terabytes.");

            }

            return 1;

        }

        img_size = (uint64_t)sval;

    }

    if (options && is_help_option(options)) {

        return print_block_option_help(filename, fmt);

    }

    bdrv_img_create(filename, fmt, base_filename, base_fmt,

                    options, img_size, BDRV_O_FLAGS, &local_err, quiet);

    if (error_is_set(&local_err)) {

        error_report("%s", error_get_pretty(local_err));

        error_free(local_err);

        return 1;

    }

    return 0;

}

static void dump_json_image_check(ImageCheck *check, bool quiet)

{

    Error *errp = NULL;

    QString *str;

    QmpOutputVisitor *ov = qmp_output_visitor_new();

    QObject *obj;

    visit_type_ImageCheck(qmp_output_get_visitor(ov),

                          &check, NULL, &errp);

    obj = qmp_output_get_qobject(ov);

    str = qobject_to_json_pretty(obj);

    assert(str != NULL);

    qprintf(quiet, "%s\n", qstring_get_str(str));

    qobject_decref(obj);

    qmp_output_visitor_cleanup(ov);

    QDECREF(str);

}

static void dump_human_image_check(ImageCheck *check, bool quiet)

{

    if (!(check->corruptions || check->leaks || check->check_errors)) {

        qprintf(quiet, "No errors were found on the image.\n");

    } else {

        if (check->corruptions) {

            qprintf(quiet, "\n%" PRId64 " errors were found on the image.\n"

                    "Data may be corrupted, or further writes to the image "

                    "may corrupt it.\n",

                    check->corruptions);

        }

        if (check->leaks) {

            qprintf(quiet,

                    "\n%" PRId64 " leaked clusters were found on the image.\n"

                    "This means waste of disk space, but no harm to data.\n",

                    check->leaks);

        }

        if (check->check_errors) {

            qprintf(quiet,

                    "\n%" PRId64

                    " internal errors have occurred during the check.\n",

                    check->check_errors);

        }

    }

    if (check->total_clusters != 0 && check->allocated_clusters != 0) {

        qprintf(quiet, "%" PRId64 "/%" PRId64 " = %0.2f%% allocated, "

                "%0.2f%% fragmented, %0.2f%% compressed clusters\n",

                check->allocated_clusters, check->total_clusters,

                check->allocated_clusters * 100.0 / check->total_clusters,

                check->fragmented_clusters * 100.0 / check->allocated_clusters,

                check->compressed_clusters * 100.0 /

                check->allocated_clusters);

    }

    if (check->image_end_offset) {

        qprintf(quiet,

                "Image end offset: %" PRId64 "\n", check->image_end_offset);

    }

}

static int collect_image_check(BlockDriverState *bs,

                   ImageCheck *check,

                   const char *filename,

                   const char *fmt,

                   int fix)

{

    int ret;

    BdrvCheckResult result;

    ret = bdrv_check(bs, &result, fix);

    if (ret < 0) {

        return ret;

    }

    check->filename                 = g_strdup(filename);

    check->format                   = g_strdup(bdrv_get_format_name(bs));

    check->check_errors             = result.check_errors;

    check->corruptions              = result.corruptions;

    check->has_corruptions          = result.corruptions != 0;

    check->leaks                    = result.leaks;

    check->has_leaks                = result.leaks != 0;

    check->corruptions_fixed        = result.corruptions_fixed;

    check->has_corruptions_fixed    = result.corruptions != 0;

    check->leaks_fixed              = result.leaks_fixed;

    check->has_leaks_fixed          = result.leaks != 0;

    check->image_end_offset         = result.image_end_offset;

    check->has_image_end_offset     = result.image_end_offset != 0;

    check->total_clusters           = result.bfi.total_clusters;

    check->has_total_clusters       = result.bfi.total_clusters != 0;

    check->allocated_clusters       = result.bfi.allocated_clusters;

    check->has_allocated_clusters   = result.bfi.allocated_clusters != 0;

    check->fragmented_clusters      = result.bfi.fragmented_clusters;

    check->has_fragmented_clusters  = result.bfi.fragmented_clusters != 0;

    check->compressed_clusters      = result.bfi.compressed_clusters;

    check->has_compressed_clusters  = result.bfi.compressed_clusters != 0;

    return 0;

}

/*

 * Checks an image for consistency. Exit codes:

 *

 * 0 - Check completed, image is good

 * 1 - Check not completed because of internal errors

 * 2 - Check completed, image is corrupted

 * 3 - Check completed, image has leaked clusters, but is good otherwise

 */

static int img_check(int argc, char **argv)

{

    int c, ret;

    OutputFormat output_format = OFORMAT_HUMAN;

    const char *filename, *fmt, *output;

    BlockDriverState *bs;

    int fix = 0;

    int flags = BDRV_O_FLAGS | BDRV_O_CHECK;

    ImageCheck *check;

    bool quiet = false;

    fmt = NULL;

    output = NULL;

    for(;;) {

        int option_index = 0;

        static const struct option long_options[] = {

            {"help", no_argument, 0, 'h'},

            {"format", required_argument, 0, 'f'},

            {"repair", no_argument, 0, 'r'},

            {"output", required_argument, 0, OPTION_OUTPUT},

            {0, 0, 0, 0}

        };

        c = getopt_long(argc, argv, "f:hr:q",

                        long_options, &option_index);

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'f':

            fmt = optarg;

            break;

        case 'r':

            flags |= BDRV_O_RDWR;

            if (!strcmp(optarg, "leaks")) {

                fix = BDRV_FIX_LEAKS;

            } else if (!strcmp(optarg, "all")) {

                fix = BDRV_FIX_LEAKS | BDRV_FIX_ERRORS;

            } else {

                help();

            }

            break;

        case OPTION_OUTPUT:

            output = optarg;

            break;

        case 'q':

            quiet = true;

            break;

        }

    }

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    if (output && !strcmp(output, "json")) {

        output_format = OFORMAT_JSON;

    } else if (output && !strcmp(output, "human")) {

        output_format = OFORMAT_HUMAN;

    } else if (output) {

        error_report("--output must be used with human or json as argument.");

        return 1;

    }

    bs = bdrv_new_open(filename, fmt, flags, true, quiet);

    if (!bs) {

        return 1;

    }

    check = g_new0(ImageCheck, 1);

    ret = collect_image_check(bs, check, filename, fmt, fix);

    if (ret == -ENOTSUP) {

        if (output_format == OFORMAT_HUMAN) {

            error_report("This image format does not support checks");

        }

        ret = 1;

        goto fail;

    }

    if (check->corruptions_fixed || check->leaks_fixed) {

        int corruptions_fixed, leaks_fixed;

        leaks_fixed         = check->leaks_fixed;

        corruptions_fixed   = check->corruptions_fixed;

        if (output_format == OFORMAT_HUMAN) {

            qprintf(quiet,

                    "The following inconsistencies were found and repaired:\n\n"

                    "    %" PRId64 " leaked clusters\n"

                    "    %" PRId64 " corruptions\n\n"

                    "Double checking the fixed image now...\n",

                    check->leaks_fixed,

                    check->corruptions_fixed);

        }

        ret = collect_image_check(bs, check, filename, fmt, 0);

        check->leaks_fixed          = leaks_fixed;

        check->corruptions_fixed    = corruptions_fixed;

    }

    switch (output_format) {

    case OFORMAT_HUMAN:

        dump_human_image_check(check, quiet);

        break;

    case OFORMAT_JSON:

        dump_json_image_check(check, quiet);

        break;

    }

    if (ret || check->check_errors) {

        ret = 1;

        goto fail;

    }

    if (check->corruptions) {

        ret = 2;

    } else if (check->leaks) {

        ret = 3;

    } else {

        ret = 0;

    }

fail:

    qapi_free_ImageCheck(check);

    bdrv_delete(bs);

    return ret;

}

static int img_commit(int argc, char **argv)

{

    int c, ret, flags;

    const char *filename, *fmt, *cache;

    BlockDriverState *bs;

    bool quiet = false;

    fmt = NULL;

    cache = BDRV_DEFAULT_CACHE;

    for(;;) {

        c = getopt(argc, argv, "f:ht:q");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'f':

            fmt = optarg;

            break;

        case 't':

            cache = optarg;

            break;

        case 'q':

            quiet = true;

            break;

        }

    }

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    flags = BDRV_O_RDWR;

    ret = bdrv_parse_cache_flags(cache, &flags);

    if (ret < 0) {

        error_report("Invalid cache option: %s", cache);

        return -1;

    }

    bs = bdrv_new_open(filename, fmt, flags, true, quiet);

    if (!bs) {

        return 1;

    }

    ret = bdrv_commit(bs);

    switch(ret) {

    case 0:

        qprintf(quiet, "Image committed.\n");

        break;

    case -ENOENT:

        error_report("No disk inserted");

        break;

    case -EACCES:

        error_report("Image is read-only");

        break;

    case -ENOTSUP:

        error_report("Image is already committed");

        break;

    default:

        error_report("Error while committing image");

        break;

    }

    bdrv_delete(bs);

    if (ret) {

        return 1;

    }

    return 0;

}

/*

 * Returns true iff the first sector pointed to by 'buf' contains at least

 * a non-NUL byte.

 *

 * 'pnum' is set to the number of sectors (including and immediately following

 * the first one) that are known to be in the same allocated/unallocated state.

 */

static int is_allocated_sectors(const uint8_t *buf, int n, int *pnum)

{

    bool is_zero;

    int i;

    if (n <= 0) {

        *pnum = 0;

        return 0;

    }

    is_zero = buffer_is_zero(buf, 512);

    for(i = 1; i < n; i++) {

        buf += 512;

        if (is_zero != buffer_is_zero(buf, 512)) {

            break;

        }

    }

    *pnum = i;

    return !is_zero;

}

/*

 * Like is_allocated_sectors, but if the buffer starts with a used sector,

 * up to 'min' consecutive sectors containing zeros are ignored. This avoids

 * breaking up write requests for only small sparse areas.

 */

static int is_allocated_sectors_min(const uint8_t *buf, int n, int *pnum,

    int min)

{

    int ret;

    int num_checked, num_used;

    if (n < min) {

        min = n;

    }

    ret = is_allocated_sectors(buf, n, pnum);

    if (!ret) {

        return ret;

    }

    num_used = *pnum;

    buf += BDRV_SECTOR_SIZE * *pnum;

    n -= *pnum;

    num_checked = num_used;

    while (n > 0) {

        ret = is_allocated_sectors(buf, n, pnum);

        buf += BDRV_SECTOR_SIZE * *pnum;

        n -= *pnum;

        num_checked += *pnum;

        if (ret) {

            num_used = num_checked;

        } else if (*pnum >= min) {

            break;

        }

    }

    *pnum = num_used;

    return 1;

}

/*

 * Compares two buffers sector by sector. Returns 0 if the first sector of both

 * buffers matches, non-zero otherwise.

 *

 * pnum is set to the number of sectors (including and immediately following

 * the first one) that are known to have the same comparison result

 */

static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,

    int *pnum)

{

    int res, i;

    if (n <= 0) {

        *pnum = 0;

        return 0;

    }

    res = !!memcmp(buf1, buf2, 512);

    for(i = 1; i < n; i++) {

        buf1 += 512;

        buf2 += 512;

        if (!!memcmp(buf1, buf2, 512) != res) {

            break;

        }

    }

    *pnum = i;

    return res;

}

#define IO_BUF_SIZE (2 * 1024 * 1024)

static int64_t sectors_to_bytes(int64_t sectors)

{

    return sectors << BDRV_SECTOR_BITS;

}

static int64_t sectors_to_process(int64_t total, int64_t from)

{

    return MIN(total - from, IO_BUF_SIZE >> BDRV_SECTOR_BITS);

}

/*

 * Check if passed sectors are empty (not allocated or contain only 0 bytes)

 *

 * Returns 0 in case sectors are filled with 0, 1 if sectors contain non-zero

 * data and negative value on error.

 *

 * @param bs:  Driver used for accessing file

 * @param sect_num: Number of first sector to check

 * @param sect_count: Number of sectors to check