--- qemu/qemu-img.c 2018/04/24 16:47:25 1.1.1.4 +++ qemu/qemu-img.c 2018/04/24 16:50:44 1.1.1.5 @@ -22,6 +22,7 @@ * THE SOFTWARE. */ #include "qemu-common.h" +#include "osdep.h" #include "block_int.h" #include @@ -30,42 +31,10 @@ #include #endif -void *get_mmap_addr(unsigned long size) -{ - return NULL; -} - -void qemu_free(void *ptr) -{ - free(ptr); -} +/* Default to cache=writeback as data integrity is not important for qemu-tcg. */ +#define BRDV_O_FLAGS BDRV_O_CACHE_WB -void *qemu_malloc(size_t size) -{ - return malloc(size); -} - -void *qemu_mallocz(size_t size) -{ - void *ptr; - ptr = qemu_malloc(size); - if (!ptr) - return NULL; - memset(ptr, 0, size); - return ptr; -} - -char *qemu_strdup(const char *str) -{ - char *ptr; - ptr = qemu_malloc(strlen(str) + 1); - if (!ptr) - return NULL; - strcpy(ptr, str); - return ptr; -} - -static void __attribute__((noreturn)) error(const char *fmt, ...) +static void QEMU_NORETURN error(const char *fmt, ...) { va_list ap; va_start(ap, fmt); @@ -81,6 +50,7 @@ static void format_print(void *opaque, c 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" @@ -90,23 +60,37 @@ static void help(void) "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] filename [filename2 [...]] [-O output_fmt] output_filename\n" + " convert [-c] [-e] [-6] [-f fmt] [-O output_fmt] [-B output_base_image] filename [filename2 [...]] output_filename\n" " info [-f fmt] filename\n" + " snapshot [-l | -a snapshot | -c snapshot | -d snapshot] filename\n" "\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" + " 'output_base_image' forces the output image to be created as a copy on write\n" + " image of the specified base image; 'output_base_image' should have the same\n" + " content as the input's base image, however the path, image format, etc may\n" + " differ\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 kilobytes. Optional suffixes\n" + " 'M' (megabyte, 1024 * 1024) and 'G' (gigabyte, 1024 * 1024 * 1024) are" + " supported any @code{k} or @code{K} is ignored\n" " 'output_filename' is the destination disk image filename\n" " 'output_fmt' is the destination 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" + " '-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("\nSupported format:"); + printf("\nSupported formats:"); bdrv_iterate_format(format_print, NULL); printf("\n"); exit(1); @@ -217,7 +201,7 @@ static BlockDriverState *bdrv_new_open(c } else { drv = NULL; } - if (bdrv_open2(bs, filename, 0, drv) < 0) { + if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) { error("Could not open '%s'", filename); } if (bdrv_is_encrypted(bs)) { @@ -348,7 +332,7 @@ static int img_commit(int argc, char **a } else { drv = NULL; } - if (bdrv_open2(bs, filename, 0, drv) < 0) { + if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) { error("Could not open '%s'", filename); } ret = bdrv_commit(bs); @@ -385,6 +369,13 @@ static int is_not_zero(const uint8_t *se 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; @@ -408,7 +399,7 @@ static int is_allocated_sectors(const ui 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; + const char *fmt, *out_fmt, *out_baseimg, *out_filename; BlockDriver *drv; BlockDriverState **bs, *out_bs; int64_t total_sectors, nb_sectors, sector_num, bs_offset; @@ -419,9 +410,10 @@ static int img_convert(int argc, char ** 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:hce6"); if (c == -1) break; switch(c) { @@ -434,6 +426,9 @@ static int img_convert(int argc, char ** case 'O': out_fmt = optarg; break; + case 'B': + out_baseimg = optarg; + break; case 'c': flags |= BLOCK_FLAG_COMPRESS; break; @@ -450,6 +445,9 @@ static int img_convert(int argc, char ** 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"); bs = calloc(bs_n, sizeof(BlockDriverState *)); if (!bs) @@ -476,7 +474,7 @@ static int img_convert(int argc, char ** 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 = bdrv_create(drv, out_filename, total_sectors, out_baseimg, flags); if (ret < 0) { if (ret == -ENOTSUP) { error("Formatting not supported for file format '%s'", fmt); @@ -555,7 +553,7 @@ static int img_convert(int argc, char ** /* signal EOF to align */ bdrv_write_compressed(out_bs, 0, NULL, 0); } else { - sector_num = 0; + sector_num = 0; // total number of sectors converted so far for(;;) { nb_sectors = total_sectors - sector_num; if (nb_sectors <= 0) @@ -578,6 +576,20 @@ static int img_convert(int argc, char ** if (n > bs_offset + bs_sectors - sector_num) n = bs_offset + bs_sectors - sector_num; + /* 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; + } + if (bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n) < 0) error("error while reading"); /* NOTE: at the same time we convert, we do not write zero @@ -585,7 +597,10 @@ static int img_convert(int argc, char ** 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 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 (out_baseimg || is_allocated_sectors(buf1, n, &n1)) { if (bdrv_write(out_bs, sector_num, buf1, n1) < 0) error("error while writing"); } @@ -691,7 +706,7 @@ static int img_info(int argc, char **arg } else { drv = NULL; } - if (bdrv_open2(bs, filename, 0, drv) < 0) { + if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) { error("Could not open '%s'", filename); } bdrv_get_format(bs, fmt_name, sizeof(fmt_name)); @@ -699,7 +714,7 @@ static int img_info(int argc, char **arg 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); @@ -715,6 +730,10 @@ static int img_info(int argc, char **arg if (bdrv_get_info(bs, &bdi) >= 0) { if (bdi.cluster_size != 0) printf("cluster_size: %d\n", bdi.cluster_size); + if (bdi.highest_alloc) + printf("highest_alloc: %" PRId64 "\n", bdi.highest_alloc); + if (bdi.num_free_bytes) + printf("num_free_bytes: %" PRId64 "\n", bdi.num_free_bytes); } bdrv_get_backing_filename(bs, backing_filename, sizeof(backing_filename)); if (backing_filename[0] != '\0') { @@ -729,6 +748,115 @@ static int img_info(int argc, char **arg return 0; } +#define SNAPSHOT_LIST 1 +#define SNAPSHOT_CREATE 2 +#define SNAPSHOT_APPLY 3 +#define SNAPSHOT_DELETE 4 + +static void img_snapshot(int argc, char **argv) +{ + BlockDriverState *bs; + QEMUSnapshotInfo sn; + char *filename, *snapshot_name = NULL; + int c, ret; + int action = 0; + qemu_timeval tv; + + /* Parse commandline parameters */ + for(;;) { + c = getopt(argc, argv, "la:c:d:h"); + if (c == -1) + break; + switch(c) { + case 'h': + help(); + return; + case 'l': + if (action) { + help(); + return; + } + action = SNAPSHOT_LIST; + break; + case 'a': + if (action) { + help(); + return; + } + action = SNAPSHOT_APPLY; + snapshot_name = optarg; + break; + case 'c': + if (action) { + help(); + return; + } + action = SNAPSHOT_CREATE; + snapshot_name = optarg; + break; + case 'd': + if (action) { + help(); + return; + } + action = SNAPSHOT_DELETE; + snapshot_name = optarg; + break; + } + } + + if (optind >= argc) + help(); + filename = argv[optind++]; + + /* Open the image */ + bs = bdrv_new(""); + if (!bs) + error("Not enough memory"); + + if (bdrv_open2(bs, filename, 0, NULL) < 0) { + error("Could not open '%s'", filename); + } + + /* 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); +} + int main(int argc, char **argv) { const char *cmd; @@ -737,7 +865,7 @@ int main(int argc, char **argv) if (argc < 2) help(); cmd = argv[1]; - optind++; + argc--; argv++; if (!strcmp(cmd, "create")) { img_create(argc, argv); } else if (!strcmp(cmd, "commit")) { @@ -746,6 +874,8 @@ int main(int argc, char **argv) img_convert(argc, argv); } else if (!strcmp(cmd, "info")) { img_info(argc, argv); + } else if (!strcmp(cmd, "snapshot")) { + img_snapshot(argc, argv); } else { help(); }