diff options
| -rw-r--r-- | block.c | 66 |
1 files changed, 38 insertions, 28 deletions
@@ -518,22 +518,16 @@ BlockDriver *bdrv_find_protocol(const char *filename) return NULL; } -static int find_image_format(const char *filename, BlockDriver **pdrv) +static int find_image_format(BlockDriverState *bs, const char *filename, + BlockDriver **pdrv) { - int ret, score, score_max; + int score, score_max; BlockDriver *drv1, *drv; uint8_t buf[2048]; - BlockDriverState *bs; - - ret = bdrv_file_open(&bs, filename, 0); - if (ret < 0) { - *pdrv = NULL; - return ret; - } + int ret = 0; /* Return the raw BlockDriver * to scsi-generic devices or empty drives */ if (bs->sg || !bdrv_is_inserted(bs)) { - bdrv_delete(bs); drv = bdrv_find_format("raw"); if (!drv) { ret = -ENOENT; @@ -543,7 +537,6 @@ static int find_image_format(const char *filename, BlockDriver **pdrv) } ret = bdrv_pread(bs, 0, buf, sizeof(buf)); - bdrv_delete(bs); if (ret < 0) { *pdrv = NULL; return ret; @@ -657,7 +650,8 @@ static int bdrv_open_flags(BlockDriverState *bs, int flags) /* * Common part for opening disk images and files */ -static int bdrv_open_common(BlockDriverState *bs, const char *filename, +static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file, + const char *filename, int flags, BlockDriver *drv) { int ret, open_flags; @@ -691,12 +685,16 @@ static int bdrv_open_common(BlockDriverState *bs, const char *filename, /* Open the image, either directly or using a protocol */ if (drv->bdrv_file_open) { - ret = drv->bdrv_file_open(bs, filename, open_flags); - } else { - ret = bdrv_file_open(&bs->file, filename, open_flags); - if (ret >= 0) { - ret = drv->bdrv_open(bs, open_flags); + if (file != NULL) { + bdrv_swap(file, bs); + ret = 0; + } else { + ret = drv->bdrv_file_open(bs, filename, open_flags); } + } else { + assert(file != NULL); + bs->file = file; + ret = drv->bdrv_open(bs, open_flags); } if (ret < 0) { @@ -716,10 +714,7 @@ static int bdrv_open_common(BlockDriverState *bs, const char *filename, return 0; free_and_fail: - if (bs->file) { - bdrv_delete(bs->file); - bs->file = NULL; - } + bs->file = NULL; g_free(bs->opaque); bs->opaque = NULL; bs->drv = NULL; @@ -741,7 +736,7 @@ int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags) } bs = bdrv_new(""); - ret = bdrv_open_common(bs, filename, flags, drv); + ret = bdrv_open_common(bs, NULL, filename, flags, drv); if (ret < 0) { bdrv_delete(bs); return ret; @@ -796,6 +791,7 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags, int ret; /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */ char tmp_filename[PATH_MAX + 1]; + BlockDriverState *file = NULL; if (flags & BDRV_O_SNAPSHOT) { BlockDriverState *bs1; @@ -855,25 +851,36 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags, bs->is_temporary = 1; } + /* Open image file without format layer */ + if (flags & BDRV_O_RDWR) { + flags |= BDRV_O_ALLOW_RDWR; + } + + ret = bdrv_file_open(&file, filename, bdrv_open_flags(bs, flags)); + if (ret < 0) { + return ret; + } + /* Find the right image format driver */ if (!drv) { - ret = find_image_format(filename, &drv); + ret = find_image_format(file, filename, &drv); } if (!drv) { goto unlink_and_fail; } - if (flags & BDRV_O_RDWR) { - flags |= BDRV_O_ALLOW_RDWR; - } - /* Open the image */ - ret = bdrv_open_common(bs, filename, flags, drv); + ret = bdrv_open_common(bs, file, filename, flags, drv); if (ret < 0) { goto unlink_and_fail; } + if (bs->file != file) { + bdrv_delete(file); + file = NULL; + } + /* If there is a backing file, use it */ if ((flags & BDRV_O_NO_BACKING) == 0) { ret = bdrv_open_backing_file(bs); @@ -895,6 +902,9 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags, return 0; unlink_and_fail: + if (file != NULL) { + bdrv_delete(file); + } if (bs->is_temporary) { unlink(filename); } |