X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=qemu-img.c;h=e300f911cb5b05b7e68323ad47d80129f4caf8cc;hb=f4594a3be005ea96e276a1354184258f5ef3b8da;hp=309a746da7838cd84f6e1dc153efb8d2371de887;hpb=ca10f86763f58b7b3667e2ca7d26db3dc810eb20;p=mirror_qemu.git diff --git a/qemu-img.c b/qemu-img.c index 309a746da7..e300f911cb 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -22,22 +22,30 @@ * THE SOFTWARE. */ #include "qemu-common.h" +#include "qemu-option.h" +#include "osdep.h" #include "block_int.h" -#include +#include #ifdef _WIN32 -#define WIN32_LEAN_AND_MEAN #include #endif -static void __attribute__((noreturn)) error(const char *fmt, ...) +typedef struct img_cmd_t { + const char *name; + int (*handler)(int argc, char **argv); +} img_cmd_t; + +/* Default to cache=writeback as data integrity is not important for qemu-tcg. */ +#define BDRV_O_FLAGS BDRV_O_CACHE_WB + +static void error(const char *fmt, ...) { va_list ap; va_start(ap, fmt); fprintf(stderr, "qemu-img: "); vfprintf(stderr, fmt, ap); fprintf(stderr, "\n"); - exit(1); va_end(ap); } @@ -46,32 +54,46 @@ static void format_print(void *opaque, const char *name) printf(" %s", name); } +/* Please keep in synch with qemu-img.texi */ static void help(void) { - printf("qemu-img version " QEMU_VERSION ", Copyright (c) 2004-2008 Fabrice Bellard\n" + 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" - " create [-e] [-6] [-b base_image] [-f fmt] filename [size]\n" - " commit [-f fmt] filename\n" - " convert [-c] [-e] [-6] [-f fmt] [-O output_fmt] filename [filename2 [...]] output_filename\n" - " info [-f fmt] filename\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" - " 'base_image' is the read-only disk image which is used as base for a copy on\n" - " write image; the copy on write image only stores the modified data\n" " 'fmt' is the disk image format. It is guessed automatically in most cases\n" - " 'size' is the disk image size in kilobytes. Optional suffixes 'M' (megabyte)\n" - " and 'G' (gigabyte) are supported\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" - " '-e' indicates that the target image must be encrypted (qcow format only)\n" - " '-6' indicates that the target image must use compatibility level 6 (vmdk format only)\n" - ); - printf("\nSupported format:"); + " '-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" + "\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"; + + printf("%s\nSupported formats:", help_msg); bdrv_iterate_format(format_print, NULL); printf("\n"); exit(1); @@ -166,54 +188,104 @@ static int read_password(char *buf, int buf_size) #endif static BlockDriverState *bdrv_new_open(const char *filename, - const char *fmt) + const char *fmt, + int flags) { BlockDriverState *bs; BlockDriver *drv; char password[256]; bs = bdrv_new(""); - if (!bs) + if (!bs) { error("Not enough memory"); + goto fail; + } if (fmt) { drv = bdrv_find_format(fmt); - if (!drv) + if (!drv) { error("Unknown file format '%s'", fmt); + goto fail; + } } else { drv = NULL; } - if (bdrv_open2(bs, filename, 0, drv) < 0) { + if (bdrv_open(bs, filename, flags, drv) < 0) { error("Could not open '%s'", filename); + goto fail; } if (bdrv_is_encrypted(bs)) { printf("Disk image '%s' is encrypted.\n", filename); - if (read_password(password, sizeof(password)) < 0) + if (read_password(password, sizeof(password)) < 0) { error("No password given"); - if (bdrv_set_key(bs, password) < 0) + goto fail; + } + if (bdrv_set_key(bs, password) < 0) { error("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, + int flags, const char *base_filename, const char *base_fmt) +{ + if (flags & BLOCK_FLAG_ENCRYPT) { + if (set_option_parameter(list, BLOCK_OPT_ENCRYPT, "on")) { + error("Encryption not supported for file format '%s'", fmt); + return -1; + } + } + if (flags & BLOCK_FLAG_COMPAT6) { + if (set_option_parameter(list, BLOCK_OPT_COMPAT6, "on")) { + error("VMDK version 6 not supported for file format '%s'", fmt); + return -1; + } + } + + if (base_filename) { + if (set_option_parameter(list, BLOCK_OPT_BACKING_FILE, base_filename)) { + error("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("Backing file format not supported for file format '%s'", fmt); + return -1; + } + } + return 0; } static int img_create(int argc, char **argv) { - int c, ret, flags; + int c, ret = 0, flags; const char *fmt = "raw"; + const char *base_fmt = NULL; const char *filename; const char *base_filename = NULL; - uint64_t size; - const char *p; - BlockDriver *drv; + BlockDriver *drv, *proto_drv; + QEMUOptionParameter *param = NULL, *create_options = NULL; + char *options = NULL; flags = 0; for(;;) { - c = getopt(argc, argv, "b:f:he6"); + c = getopt(argc, argv, "F:b:f:he6o:"); if (c == -1) break; switch(c) { case 'h': help(); break; + case 'F': + base_fmt = optarg; + break; case 'b': base_filename = optarg; break; @@ -226,64 +298,147 @@ static int img_create(int argc, char **argv) case '6': flags |= BLOCK_FLAG_COMPAT6; break; + case 'o': + options = optarg; + break; } } + + /* Get the filename */ if (optind >= argc) help(); filename = argv[optind++]; - size = 0; - if (base_filename) { - BlockDriverState *bs; - bs = bdrv_new_open(base_filename, NULL); - bdrv_get_geometry(bs, &size); - size *= 512; - bdrv_delete(bs); - } else { - if (optind >= argc) - help(); - p = argv[optind]; - size = strtoul(p, (char **)&p, 0); - if (*p == 'M') { - size *= 1024 * 1024; - } else if (*p == 'G') { - size *= 1024 * 1024 * 1024; - } else if (*p == 'k' || *p == 'K' || *p == '\0') { - size *= 1024; - } else { - help(); - } - } + + /* Find driver and parse its options */ drv = bdrv_find_format(fmt); - if (!drv) + if (!drv) { error("Unknown file format '%s'", fmt); - printf("Formatting '%s', fmt=%s", - filename, fmt); - if (flags & BLOCK_FLAG_ENCRYPT) - printf(", encrypted"); - if (flags & BLOCK_FLAG_COMPAT6) - printf(", compatibility level=6"); - if (base_filename) { - printf(", backing_file=%s", - base_filename); + return 1; + } + + proto_drv = bdrv_find_protocol(filename); + if (!proto_drv) { + error("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); + + if (options && !strcmp(options, "?")) { + print_option_help(create_options); + goto out; + } + + /* Create parameter list with default values */ + param = parse_option_parameters("", create_options, param); + set_option_parameter_int(param, BLOCK_OPT_SIZE, -1); + + /* Parse -o options */ + if (options) { + param = parse_option_parameters(options, create_options, param); + if (param == NULL) { + error("Invalid options for file format '%s'.", fmt); + ret = -1; + goto out; + } + } + + /* Add size to parameters */ + if (optind < argc) { + set_option_parameter(param, BLOCK_OPT_SIZE, argv[optind++]); + } + + /* Add old-style options to parameters */ + ret = add_old_style_options(fmt, param, flags, base_filename, base_fmt); + if (ret < 0) { + goto out; + } + + // The size for the image must always be specified, with one exception: + // If we are using a backing file, we can obtain the size from there + if (get_option_parameter(param, BLOCK_OPT_SIZE)->value.n == -1) { + + QEMUOptionParameter *backing_file = + get_option_parameter(param, BLOCK_OPT_BACKING_FILE); + QEMUOptionParameter *backing_fmt = + get_option_parameter(param, BLOCK_OPT_BACKING_FMT); + + if (backing_file && backing_file->value.s) { + BlockDriverState *bs; + uint64_t size; + const char *fmt = NULL; + char buf[32]; + + if (backing_fmt && backing_fmt->value.s) { + if (bdrv_find_format(backing_fmt->value.s)) { + fmt = backing_fmt->value.s; + } else { + error("Unknown backing file format '%s'", + backing_fmt->value.s); + ret = -1; + goto out; + } + } + + bs = bdrv_new_open(backing_file->value.s, fmt, BDRV_O_FLAGS); + if (!bs) { + ret = -1; + goto out; + } + bdrv_get_geometry(bs, &size); + size *= 512; + bdrv_delete(bs); + + snprintf(buf, sizeof(buf), "%" PRId64, size); + set_option_parameter(param, BLOCK_OPT_SIZE, buf); + } else { + error("Image creation needs a size parameter"); + ret = -1; + goto out; + } } - printf(", size=%" PRIu64 " kB\n", size / 1024); - ret = bdrv_create(drv, filename, size / 512, base_filename, flags); + + printf("Formatting '%s', fmt=%s ", filename, fmt); + print_option_parameters(param); + puts(""); + + ret = bdrv_create(drv, filename, param); + free_option_parameters(create_options); + free_option_parameters(param); + if (ret < 0) { if (ret == -ENOTSUP) { error("Formatting or formatting option not supported for file format '%s'", fmt); + } else if (ret == -EFBIG) { + error("The image size is too large for file format '%s'", fmt); } else { - error("Error while formatting"); + error("%s: error while creating %s: %s", filename, fmt, strerror(-ret)); } } +out: + if (ret) { + return 1; + } return 0; } -static int img_commit(int argc, char **argv) +/* + * 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; const char *filename, *fmt; - BlockDriver *drv; BlockDriverState *bs; + BdrvCheckResult result; fmt = NULL; for(;;) { @@ -303,18 +458,85 @@ static int img_commit(int argc, char **argv) help(); filename = argv[optind++]; - bs = bdrv_new(""); - if (!bs) - error("Not enough memory"); - if (fmt) { - drv = bdrv_find_format(fmt); - if (!drv) - error("Unknown file format '%s'", fmt); + bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS); + if (!bs) { + return 1; + } + ret = bdrv_check(bs, &result); + + if (ret == -ENOTSUP) { + error("This image format does not support checks"); + bdrv_delete(bs); + return 1; + } + + if (!(result.corruptions || result.leaks || result.check_errors)) { + printf("No errors were found on the image.\n"); } else { - drv = NULL; + if (result.corruptions) { + printf("\n%d errors were found on the image.\n" + "Data may be corrupted, or further writes to the image " + "may corrupt it.\n", + result.corruptions); + } + + if (result.leaks) { + printf("\n%d leaked clusters were found on the image.\n" + "This means waste of disk space, but no harm to data.\n", + result.leaks); + } + + if (result.check_errors) { + printf("\n%d internal errors have occurred during the check.\n", + result.check_errors); + } } - if (bdrv_open2(bs, filename, 0, drv) < 0) { - error("Could not open '%s'", filename); + + bdrv_delete(bs); + + if (ret < 0 || result.check_errors) { + printf("\nAn error has occurred during the check: %s\n" + "The check is not complete and may have missed error.\n", + strerror(-ret)); + return 1; + } + + if (result.corruptions) { + return 2; + } else if (result.leaks) { + return 3; + } else { + return 0; + } +} + +static int img_commit(int argc, char **argv) +{ + int c, ret; + const char *filename, *fmt; + BlockDriverState *bs; + + fmt = NULL; + for(;;) { + c = getopt(argc, argv, "f:h"); + if (c == -1) + break; + switch(c) { + case 'h': + help(); + break; + case 'f': + fmt = optarg; + break; + } + } + if (optind >= argc) + help(); + filename = argv[optind++]; + + bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR); + if (!bs) { + return 1; } ret = bdrv_commit(bs); switch(ret) { @@ -336,6 +558,9 @@ static int img_commit(int argc, char **argv) } bdrv_delete(bs); + if (ret) { + return 1; + } return 0; } @@ -350,6 +575,13 @@ static int is_not_zero(const uint8_t *sector, int len) 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) { int v, i; @@ -368,25 +600,59 @@ static int is_allocated_sectors(const uint8_t *buf, int n, int *pnum) return v; } -#define IO_BUF_SIZE 65536 +/* + * 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 int img_convert(int argc, char **argv) { - int c, ret, n, n1, bs_n, bs_i, flags, cluster_size, cluster_sectors; - const char *fmt, *out_fmt, *out_filename; - BlockDriver *drv; - BlockDriverState **bs, *out_bs; + int c, ret = 0, n, n1, bs_n, bs_i, flags, cluster_size, cluster_sectors; + const char *fmt, *out_fmt, *out_baseimg, *out_filename; + BlockDriver *drv, *proto_drv; + BlockDriverState **bs = NULL, *out_bs = NULL; int64_t total_sectors, nb_sectors, sector_num, bs_offset; uint64_t bs_sectors; - uint8_t buf[IO_BUF_SIZE]; + uint8_t * buf = NULL; const uint8_t *buf1; BlockDriverInfo bdi; + QEMUOptionParameter *param = NULL, *create_options = NULL; + char *options = NULL; fmt = NULL; out_fmt = "raw"; + out_baseimg = NULL; flags = 0; for(;;) { - c = getopt(argc, argv, "f:O:hce6"); + c = getopt(argc, argv, "f:O:B:hce6o:"); if (c == -1) break; switch(c) { @@ -399,6 +665,9 @@ static int img_convert(int argc, char **argv) case 'O': out_fmt = optarg; break; + case 'B': + out_baseimg = optarg; + break; case 'c': flags |= BLOCK_FLAG_COMPRESS; break; @@ -408,6 +677,9 @@ static int img_convert(int argc, char **argv) case '6': flags |= BLOCK_FLAG_COMPAT6; break; + case 'o': + options = optarg; + break; } } @@ -415,53 +687,125 @@ static int img_convert(int argc, char **argv) if (bs_n < 1) help(); out_filename = argv[argc - 1]; + + if (bs_n > 1 && out_baseimg) { + error("-B makes no sense when concatenating multiple input images"); + return 1; + } bs = calloc(bs_n, sizeof(BlockDriverState *)); - if (!bs) + if (!bs) { error("Out of memory"); + return 1; + } total_sectors = 0; for (bs_i = 0; bs_i < bs_n; bs_i++) { - bs[bs_i] = bdrv_new_open(argv[optind + bs_i], fmt); - if (!bs[bs_i]) + bs[bs_i] = bdrv_new_open(argv[optind + bs_i], fmt, BDRV_O_FLAGS); + if (!bs[bs_i]) { error("Could not open '%s'", argv[optind + bs_i]); + ret = -1; + goto out; + } bdrv_get_geometry(bs[bs_i], &bs_sectors); total_sectors += bs_sectors; } + /* Find driver and parse its options */ drv = bdrv_find_format(out_fmt); - if (!drv) + if (!drv) { error("Unknown file format '%s'", out_fmt); - if (flags & BLOCK_FLAG_COMPRESS && drv != &bdrv_qcow && drv != &bdrv_qcow2) - error("Compression not supported for this file format"); - if (flags & BLOCK_FLAG_ENCRYPT && drv != &bdrv_qcow && drv != &bdrv_qcow2) - error("Encryption not supported for this file format"); - if (flags & BLOCK_FLAG_COMPAT6 && drv != &bdrv_vmdk) - error("Alternative compatibility level not supported for this file format"); - if (flags & BLOCK_FLAG_ENCRYPT && flags & BLOCK_FLAG_COMPRESS) - error("Compression and encryption not supported at the same time"); - - ret = bdrv_create(drv, out_filename, total_sectors, NULL, flags); + ret = -1; + goto out; + } + + proto_drv = bdrv_find_protocol(out_filename); + if (!proto_drv) { + error("Unknown protocol '%s'", out_filename); + ret = -1; + goto out; + } + + create_options = append_option_parameters(create_options, + drv->create_options); + create_options = append_option_parameters(create_options, + proto_drv->create_options); + if (options && !strcmp(options, "?")) { + print_option_help(create_options); + goto out; + } + + if (options) { + param = parse_option_parameters(options, create_options, param); + if (param == NULL) { + error("Invalid options for file format '%s'.", out_fmt); + ret = -1; + goto out; + } + } else { + param = parse_option_parameters("", create_options, param); + } + + set_option_parameter_int(param, BLOCK_OPT_SIZE, total_sectors * 512); + ret = add_old_style_options(out_fmt, param, flags, out_baseimg, NULL); + if (ret < 0) { + goto out; + } + + /* Check if compression is supported */ + if (flags & BLOCK_FLAG_COMPRESS) { + QEMUOptionParameter *encryption = + get_option_parameter(param, BLOCK_OPT_ENCRYPT); + + if (!drv->bdrv_write_compressed) { + error("Compression not supported for this file format"); + ret = -1; + goto out; + } + + if (encryption && encryption->value.n) { + error("Compression and encryption not supported at the same time"); + ret = -1; + goto out; + } + } + + /* Create the new image */ + ret = bdrv_create(drv, out_filename, param); if (ret < 0) { if (ret == -ENOTSUP) { - error("Formatting not supported for file format '%s'", fmt); + error("Formatting not supported for file format '%s'", out_fmt); + } else if (ret == -EFBIG) { + error("The image size is too large for file format '%s'", out_fmt); } else { - error("Error while formatting '%s'", out_filename); + error("%s: error while converting %s: %s", out_filename, out_fmt, strerror(-ret)); } + goto out; } - out_bs = bdrv_new_open(out_filename, out_fmt); + out_bs = bdrv_new_open(out_filename, out_fmt, BDRV_O_FLAGS | BDRV_O_RDWR); + if (!out_bs) { + ret = -1; + goto out; + } bs_i = 0; bs_offset = 0; bdrv_get_geometry(bs[0], &bs_sectors); + buf = qemu_malloc(IO_BUF_SIZE); if (flags & BLOCK_FLAG_COMPRESS) { - if (bdrv_get_info(out_bs, &bdi) < 0) + ret = bdrv_get_info(out_bs, &bdi); + if (ret < 0) { error("could not get block driver info"); + goto out; + } cluster_size = bdi.cluster_size; - if (cluster_size <= 0 || cluster_size > IO_BUF_SIZE) + if (cluster_size <= 0 || cluster_size > IO_BUF_SIZE) { error("invalid cluster size"); + ret = -1; + goto out; + } cluster_sectors = cluster_size >> 9; sector_num = 0; for(;;) { @@ -489,16 +833,19 @@ static int img_convert(int argc, char **argv) bs_offset += bs_sectors; bdrv_get_geometry(bs[bs_i], &bs_sectors); bs_num = 0; - /* printf("changing part: sector_num=%lld, " - "bs_i=%d, bs_offset=%lld, bs_sectors=%lld\n", - sector_num, bs_i, bs_offset, bs_sectors); */ + /* printf("changing part: sector_num=%" PRId64 ", " + "bs_i=%d, bs_offset=%" PRId64 ", bs_sectors=%" PRId64 + "\n", sector_num, bs_i, bs_offset, bs_sectors); */ } assert (bs_num < bs_sectors); nlow = (remainder > bs_sectors - bs_num) ? bs_sectors - bs_num : remainder; - if (bdrv_read(bs[bs_i], bs_num, buf2, nlow) < 0) + ret = bdrv_read(bs[bs_i], bs_num, buf2, nlow); + if (ret < 0) { error("error while reading"); + goto out; + } buf2 += nlow * 512; bs_num += nlow; @@ -510,17 +857,22 @@ static int img_convert(int argc, char **argv) if (n < cluster_sectors) memset(buf + n * 512, 0, cluster_size - n * 512); if (is_not_zero(buf, cluster_size)) { - if (bdrv_write_compressed(out_bs, sector_num, buf, - cluster_sectors) != 0) + ret = bdrv_write_compressed(out_bs, sector_num, buf, + cluster_sectors); + if (ret != 0) { error("error while compressing sector %" PRId64, sector_num); + goto out; + } } sector_num += n; } /* signal EOF to align */ bdrv_write_compressed(out_bs, 0, NULL, 0); } else { - sector_num = 0; + int has_zero_init = bdrv_has_zero_init(out_bs); + + sector_num = 0; // total number of sectors converted so far for(;;) { nb_sectors = total_sectors - sector_num; if (nb_sectors <= 0) @@ -535,24 +887,57 @@ static int img_convert(int argc, char **argv) assert (bs_i < bs_n); bs_offset += bs_sectors; bdrv_get_geometry(bs[bs_i], &bs_sectors); - /* printf("changing part: sector_num=%lld, bs_i=%d, " - "bs_offset=%lld, bs_sectors=%lld\n", + /* printf("changing part: sector_num=%" PRId64 ", bs_i=%d, " + "bs_offset=%" PRId64 ", bs_sectors=%" PRId64 "\n", sector_num, bs_i, bs_offset, bs_sectors); */ } if (n > bs_offset + bs_sectors - sector_num) n = bs_offset + bs_sectors - sector_num; - if (bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n) < 0) + if (has_zero_init) { + /* If the output image is being created as a copy on write image, + assume that sectors which are unallocated in the input image + are present in both the output's and input's base images (no + need to copy them). */ + if (out_baseimg) { + if (!bdrv_is_allocated(bs[bs_i], sector_num - bs_offset, + n, &n1)) { + sector_num += n1; + continue; + } + /* The next 'n1' sectors are allocated in the input image. Copy + only those as they may be followed by unallocated sectors. */ + n = n1; + } + } else { + n1 = n; + } + + ret = bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n); + if (ret < 0) { error("error while reading"); + goto out; + } /* NOTE: at the same time we convert, we do not write zero sectors to have a chance to compress the image. Ideally, we should add a specific call to have the info to go faster */ buf1 = buf; while (n > 0) { - if (is_allocated_sectors(buf1, n, &n1)) { - if (bdrv_write(out_bs, sector_num, buf1, n1) < 0) + /* If the output image is being created as a copy on write image, + copy all sectors even the ones containing only NUL bytes, + because they may differ from the sectors in the base image. + + If the output is to a host device, we also write out + sectors that are entirely 0, since whatever data was + already there is garbage, not 0s. */ + if (!has_zero_init || out_baseimg || + is_allocated_sectors(buf1, n, &n1)) { + ret = bdrv_write(out_bs, sector_num, buf1, n1); + if (ret < 0) { error("error while writing"); + goto out; + } } sector_num += n1; n -= n1; @@ -560,10 +945,22 @@ static int img_convert(int argc, char **argv) } } } - bdrv_delete(out_bs); - for (bs_i = 0; bs_i < bs_n; bs_i++) - bdrv_delete(bs[bs_i]); +out: + free_option_parameters(create_options); + free_option_parameters(param); + qemu_free(buf); + if (out_bs) { + bdrv_delete(out_bs); + } + for (bs_i = 0; bs_i < bs_n; bs_i++) { + if (bs[bs_i]) { + bdrv_delete(bs[bs_i]); + } + } free(bs); + if (ret) { + return 1; + } return 0; } @@ -619,7 +1016,6 @@ static int img_info(int argc, char **argv) { int c; const char *filename, *fmt; - BlockDriver *drv; BlockDriverState *bs; char fmt_name[128], size_buf[128], dsize_buf[128]; uint64_t total_sectors; @@ -646,25 +1042,16 @@ static int img_info(int argc, char **argv) help(); filename = argv[optind++]; - bs = bdrv_new(""); - if (!bs) - error("Not enough memory"); - if (fmt) { - drv = bdrv_find_format(fmt); - if (!drv) - error("Unknown file format '%s'", fmt); - } else { - drv = NULL; - } - if (bdrv_open2(bs, filename, 0, drv) < 0) { - error("Could not open '%s'", filename); + bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_NO_BACKING); + if (!bs) { + return 1; } bdrv_get_format(bs, fmt_name, sizeof(fmt_name)); bdrv_get_geometry(bs, &total_sectors); get_human_readable_size(size_buf, sizeof(size_buf), total_sectors * 512); allocated_size = get_allocated_file_size(filename); if (allocated_size < 0) - sprintf(dsize_buf, "unavailable"); + snprintf(dsize_buf, sizeof(dsize_buf), "unavailable"); else get_human_readable_size(dsize_buf, sizeof(dsize_buf), allocated_size); @@ -694,25 +1081,455 @@ static int img_info(int argc, char **argv) return 0; } +#define SNAPSHOT_LIST 1 +#define SNAPSHOT_CREATE 2 +#define SNAPSHOT_APPLY 3 +#define SNAPSHOT_DELETE 4 + +static int img_snapshot(int argc, char **argv) +{ + BlockDriverState *bs; + QEMUSnapshotInfo sn; + char *filename, *snapshot_name = NULL; + int c, ret = 0, bdrv_oflags; + int action = 0; + qemu_timeval tv; + + bdrv_oflags = BDRV_O_RDWR; + /* Parse commandline parameters */ + for(;;) { + c = getopt(argc, argv, "la:c:d:h"); + if (c == -1) + break; + switch(c) { + case 'h': + help(); + return 0; + case 'l': + if (action) { + help(); + return 0; + } + action = SNAPSHOT_LIST; + bdrv_oflags &= ~BDRV_O_RDWR; /* no need for RW */ + break; + case 'a': + if (action) { + help(); + return 0; + } + action = SNAPSHOT_APPLY; + snapshot_name = optarg; + break; + case 'c': + if (action) { + help(); + return 0; + } + action = SNAPSHOT_CREATE; + snapshot_name = optarg; + break; + case 'd': + if (action) { + help(); + return 0; + } + action = SNAPSHOT_DELETE; + snapshot_name = optarg; + break; + } + } + + if (optind >= argc) + help(); + filename = argv[optind++]; + + /* Open the image */ + bs = bdrv_new_open(filename, NULL, bdrv_oflags); + if (!bs) { + return 1; + } + + /* Perform the requested action */ + switch(action) { + case SNAPSHOT_LIST: + dump_snapshots(bs); + break; + + case SNAPSHOT_CREATE: + memset(&sn, 0, sizeof(sn)); + pstrcpy(sn.name, sizeof(sn.name), snapshot_name); + + qemu_gettimeofday(&tv); + sn.date_sec = tv.tv_sec; + sn.date_nsec = tv.tv_usec * 1000; + + ret = bdrv_snapshot_create(bs, &sn); + if (ret) + error("Could not create snapshot '%s': %d (%s)", + snapshot_name, ret, strerror(-ret)); + break; + + case SNAPSHOT_APPLY: + ret = bdrv_snapshot_goto(bs, snapshot_name); + if (ret) + error("Could not apply snapshot '%s': %d (%s)", + snapshot_name, ret, strerror(-ret)); + break; + + case SNAPSHOT_DELETE: + ret = bdrv_snapshot_delete(bs, snapshot_name); + if (ret) + error("Could not delete snapshot '%s': %d (%s)", + snapshot_name, ret, strerror(-ret)); + break; + } + + /* Cleanup */ + bdrv_delete(bs); + if (ret) { + return 1; + } + return 0; +} + +static int img_rebase(int argc, char **argv) +{ + BlockDriverState *bs, *bs_old_backing = NULL, *bs_new_backing = NULL; + BlockDriver *old_backing_drv, *new_backing_drv; + char *filename; + const char *fmt, *out_basefmt, *out_baseimg; + int c, flags, ret; + int unsafe = 0; + + /* Parse commandline parameters */ + fmt = NULL; + out_baseimg = NULL; + out_basefmt = NULL; + + for(;;) { + c = getopt(argc, argv, "uhf:F:b:"); + if (c == -1) + break; + switch(c) { + case 'h': + help(); + return 0; + case 'f': + fmt = optarg; + break; + case 'F': + out_basefmt = optarg; + break; + case 'b': + out_baseimg = optarg; + break; + case 'u': + unsafe = 1; + break; + } + } + + if ((optind >= argc) || !out_baseimg) + help(); + filename = argv[optind++]; + + /* + * Open the images. + * + * Ignore the old backing file for unsafe rebase in case we want to correct + * the reference to a renamed or moved backing file. + */ + flags = BDRV_O_FLAGS | BDRV_O_RDWR | (unsafe ? BDRV_O_NO_BACKING : 0); + bs = bdrv_new_open(filename, fmt, flags); + if (!bs) { + return 1; + } + + /* Find the right drivers for the backing files */ + old_backing_drv = NULL; + new_backing_drv = NULL; + + if (!unsafe && bs->backing_format[0] != '\0') { + old_backing_drv = bdrv_find_format(bs->backing_format); + if (old_backing_drv == NULL) { + error("Invalid format name: '%s'", bs->backing_format); + ret = -1; + goto out; + } + } + + if (out_basefmt != NULL) { + new_backing_drv = bdrv_find_format(out_basefmt); + if (new_backing_drv == NULL) { + error("Invalid format name: '%s'", out_basefmt); + ret = -1; + goto out; + } + } + + /* For safe rebasing we need to compare old and new backing file */ + if (unsafe) { + /* Make the compiler happy */ + bs_old_backing = NULL; + bs_new_backing = NULL; + } else { + char backing_name[1024]; + + bs_old_backing = bdrv_new("old_backing"); + bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name)); + ret = bdrv_open(bs_old_backing, backing_name, BDRV_O_FLAGS, + old_backing_drv); + if (ret) { + error("Could not open old backing file '%s'", backing_name); + goto out; + } + + bs_new_backing = bdrv_new("new_backing"); + ret = bdrv_open(bs_new_backing, out_baseimg, BDRV_O_FLAGS | BDRV_O_RDWR, + new_backing_drv); + if (ret) { + error("Could not open new backing file '%s'", out_baseimg); + goto out; + } + } + + /* + * Check each unallocated cluster in the COW file. If it is unallocated, + * accesses go to the backing file. We must therefore compare this cluster + * in the old and new backing file, and if they differ we need to copy it + * from the old backing file into the COW file. + * + * If qemu-img crashes during this step, no harm is done. The content of + * the image is the same as the original one at any time. + */ + if (!unsafe) { + uint64_t num_sectors; + uint64_t sector; + int n; + uint8_t * buf_old; + uint8_t * buf_new; + + buf_old = qemu_malloc(IO_BUF_SIZE); + buf_new = qemu_malloc(IO_BUF_SIZE); + + bdrv_get_geometry(bs, &num_sectors); + + for (sector = 0; sector < num_sectors; sector += n) { + + /* How many sectors can we handle with the next read? */ + if (sector + (IO_BUF_SIZE / 512) <= num_sectors) { + n = (IO_BUF_SIZE / 512); + } else { + n = num_sectors - sector; + } + + /* If the cluster is allocated, we don't need to take action */ + ret = bdrv_is_allocated(bs, sector, n, &n); + if (ret) { + continue; + } + + /* Read old and new backing file */ + ret = bdrv_read(bs_old_backing, sector, buf_old, n); + if (ret < 0) { + error("error while reading from old backing file"); + goto out; + } + ret = bdrv_read(bs_new_backing, sector, buf_new, n); + if (ret < 0) { + error("error while reading from new backing file"); + goto out; + } + + /* If they differ, we need to write to the COW file */ + uint64_t written = 0; + + while (written < n) { + int pnum; + + if (compare_sectors(buf_old + written * 512, + buf_new + written * 512, n - written, &pnum)) + { + ret = bdrv_write(bs, sector + written, + buf_old + written * 512, pnum); + if (ret < 0) { + error("Error while writing to COW image: %s", + strerror(-ret)); + goto out; + } + } + + written += pnum; + } + } + + qemu_free(buf_old); + qemu_free(buf_new); + } + + /* + * Change the backing file. All clusters that are different from the old + * backing file are overwritten in the COW file now, so the visible content + * doesn't change when we switch the backing file. + */ + ret = bdrv_change_backing_file(bs, out_baseimg, out_basefmt); + if (ret == -ENOSPC) { + error("Could not change the backing file to '%s': No space left in " + "the file header", out_baseimg); + } else if (ret < 0) { + error("Could not change the backing file to '%s': %s", + out_baseimg, strerror(-ret)); + } + + /* + * TODO At this point it is possible to check if any clusters that are + * allocated in the COW file are the same in the backing file. If so, they + * could be dropped from the COW file. Don't do this before switching the + * backing file, in case of a crash this would lead to corruption. + */ +out: + /* Cleanup */ + if (!unsafe) { + bdrv_delete(bs_old_backing); + bdrv_delete(bs_new_backing); + } + + bdrv_delete(bs); + if (ret) { + return 1; + } + return 0; +} + +static int img_resize(int argc, char **argv) +{ + int c, ret, relative; + const char *filename, *fmt, *size; + int64_t n, total_size; + BlockDriverState *bs; + QEMUOptionParameter *param; + QEMUOptionParameter resize_options[] = { + { + .name = BLOCK_OPT_SIZE, + .type = OPT_SIZE, + .help = "Virtual disk size" + }, + { NULL } + }; + + fmt = NULL; + for(;;) { + c = getopt(argc, argv, "f:h"); + if (c == -1) { + break; + } + switch(c) { + case 'h': + help(); + break; + case 'f': + fmt = optarg; + break; + } + } + if (optind + 1 >= argc) { + help(); + } + filename = argv[optind++]; + size = argv[optind++]; + + /* Choose grow, shrink, or absolute resize mode */ + switch (size[0]) { + case '+': + relative = 1; + size++; + break; + case '-': + relative = -1; + size++; + break; + default: + relative = 0; + break; + } + + /* Parse size */ + param = parse_option_parameters("", resize_options, NULL); + if (set_option_parameter(param, BLOCK_OPT_SIZE, size)) { + /* Error message already printed when size parsing fails */ + exit(1); + } + n = get_option_parameter(param, BLOCK_OPT_SIZE)->value.n; + free_option_parameters(param); + + bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR); + if (!bs) { + return 1; + } + + if (relative) { + total_size = bdrv_getlength(bs) + n * relative; + } else { + total_size = n; + } + if (total_size <= 0) { + error("New image size must be positive"); + ret = -1; + goto out; + } + + ret = bdrv_truncate(bs, total_size); + switch (ret) { + case 0: + printf("Image resized.\n"); + break; + case -ENOTSUP: + error("This image format does not support resize"); + break; + case -EACCES: + error("Image is read-only"); + break; + default: + error("Error resizing image (%d)", -ret); + break; + } +out: + bdrv_delete(bs); + if (ret) { + return 1; + } + return 0; +} + +static const img_cmd_t img_cmds[] = { +#define DEF(option, callback, arg_string) \ + { option, callback }, +#include "qemu-img-cmds.h" +#undef DEF +#undef GEN_DOCS + { NULL, NULL, }, +}; + int main(int argc, char **argv) { - const char *cmd; + const img_cmd_t *cmd; + const char *cmdname; bdrv_init(); if (argc < 2) help(); - cmd = argv[1]; - optind++; - if (!strcmp(cmd, "create")) { - img_create(argc, argv); - } else if (!strcmp(cmd, "commit")) { - img_commit(argc, argv); - } else if (!strcmp(cmd, "convert")) { - img_convert(argc, argv); - } else if (!strcmp(cmd, "info")) { - img_info(argc, argv); - } else { - help(); + cmdname = argv[1]; + argc--; argv++; + + /* find the command */ + for(cmd = img_cmds; cmd->name != NULL; cmd++) { + if (!strcmp(cmdname, cmd->name)) { + return cmd->handler(argc, argv); + } } + + /* not found */ + help(); return 0; }