diff options
| -rw-r--r-- | block-raw-posix.c | 36 | ||||
| -rw-r--r-- | qemu-img.c | 34 |
2 files changed, 55 insertions, 15 deletions
diff --git a/block-raw-posix.c b/block-raw-posix.c index 4874b8e4a4..bff822ea65 100644 --- a/block-raw-posix.c +++ b/block-raw-posix.c @@ -1378,11 +1378,47 @@ static BlockDriverAIOCB *raw_aio_ioctl(BlockDriverState *bs, } #endif /* !linux && !FreeBSD */ +#if defined(__linux__) || defined(__FreeBSD__) +static int hdev_create(const char *filename, int64_t total_size, + const char *backing_file, int flags) +{ + int fd; + int ret = 0; + struct stat stat_buf; + + if (flags || backing_file) + return -ENOTSUP; + + fd = open(filename, O_WRONLY | O_BINARY); + if (fd < 0) + return -EIO; + + if (fstat(fd, &stat_buf) < 0) + ret = -EIO; + else if (!S_ISBLK(stat_buf.st_mode)) + ret = -EIO; + else if (lseek(fd, 0, SEEK_END) < total_size * 512) + ret = -ENOSPC; + + close(fd); + return ret; +} + +#else /* !(linux || freebsd) */ + +static int hdev_create(const char *filename, int64_t total_size, + const char *backing_file, int flags) +{ + return -ENOTSUP; +} +#endif + BlockDriver bdrv_host_device = { .format_name = "host_device", .instance_size = sizeof(BDRVRawState), .bdrv_open = hdev_open, .bdrv_close = raw_close, + .bdrv_create = hdev_create, .bdrv_flush = raw_flush, #ifdef CONFIG_AIO diff --git a/qemu-img.c b/qemu-img.c index ab380c8a44..913ad34bf8 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -493,7 +493,7 @@ static int img_convert(int argc, char **argv) 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); + error("Formatting not supported for file format '%s'", out_fmt); } else { error("Error while formatting '%s'", out_filename); } @@ -592,18 +592,17 @@ static int img_convert(int argc, char **argv) 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 (drv != &bdrv_host_device) { + 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; } if (bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n) < 0) @@ -615,8 +614,13 @@ static int img_convert(int argc, char **argv) while (n > 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 (out_baseimg || is_allocated_sectors(buf1, n, &n1)) { + 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 (drv == &bdrv_host_device || out_baseimg || + is_allocated_sectors(buf1, n, &n1)) { if (bdrv_write(out_bs, sector_num, buf1, n1) < 0) error("error while writing"); } |