Am 07.11.2011 07:52, schrieb Li Zhi Hui:
> Since common file operation functions lack of error detection,
> so change them to bdrv series functions.
>
> v2: Only contains the function modified.
> v1: Fix coding style and convert file operation functions to bdrv functions.
>
> Signed-off-by: Li Zhi Hui <zhihu...@linux.vnet.ibm.com>
> ---
> block/cow.c | 35 +++++++++++++++++++++--------------
> 1 files changed, 21 insertions(+), 14 deletions(-)
>
> diff --git a/block/cow.c b/block/cow.c
> index 707c0aa..808fe31 100644
> --- a/block/cow.c
> +++ b/block/cow.c
> @@ -243,12 +243,13 @@ static void cow_close(BlockDriverState *bs)
>
> static int cow_create(const char *filename, QEMUOptionParameter *options)
> {
> - int fd, cow_fd;
> struct cow_header_v2 cow_header;
> struct stat st;
> int64_t image_sectors = 0;
> const char *image_filename = NULL;
> int ret;
> + BlockDriverState *cow_bs;
> + BlockDriverState *image_bs;
>
> /* Read out options */
> while (options && options->name) {
> @@ -260,10 +261,15 @@ static int cow_create(const char *filename,
> QEMUOptionParameter *options)
> options++;
> }
>
> - cow_fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
> - 0644);
> - if (cow_fd < 0)
> - return -errno;
> + ret = bdrv_create_file(filename, options);
> + if (ret < 0) {
> + return ret;
> + }
> +
> + ret = bdrv_file_open(&cow_bs, filename, BDRV_O_RDWR);
> + if (ret < 0) {
> + return ret;
> + }
> memset(&cow_header, 0, sizeof(cow_header));
> cow_header.magic = cpu_to_be32(COW_MAGIC);
> cow_header.version = cpu_to_be32(COW_VERSION);
> @@ -271,16 +277,16 @@ static int cow_create(const char *filename,
> QEMUOptionParameter *options)
> /* Note: if no file, we put a dummy mtime */
> cow_header.mtime = cpu_to_be32(0);
>
> - fd = open(image_filename, O_RDONLY | O_BINARY);
> - if (fd < 0) {
> - close(cow_fd);
> + ret = bdrv_file_open(&image_bs, image_filename, BDRV_O_RDWR);
> + if (ret < 0) {
> + bdrv_close(cow_bs);
> goto mtime_fail;
> }
> - if (fstat(fd, &st) != 0) {
> - close(fd);
> + if (stat(image_filename, &st) != 0) {
> + bdrv_close(image_bs);
> goto mtime_fail;
> }
> - close(fd);
> + bdrv_close(image_bs);
Why do you open image_bs? The only thing you do with it is closing it.
> cow_header.mtime = cpu_to_be32(st.st_mtime);
> mtime_fail:
> pstrcpy(cow_header.backing_file, sizeof(cow_header.backing_file),
> @@ -288,21 +294,22 @@ static int cow_create(const char *filename,
> QEMUOptionParameter *options)
> }
> cow_header.sectorsize = cpu_to_be32(512);
> cow_header.size = cpu_to_be64(image_sectors * 512);
> - ret = qemu_write_full(cow_fd, &cow_header, sizeof(cow_header));
> + ret = bdrv_pwrite(cow_bs, 0, &cow_header, sizeof(cow_header));
> if (ret != sizeof(cow_header)) {
> ret = -errno;
This is wrong, ret already has the right value, and errno might be
different.
> goto exit;
> }
>
> /* resize to include at least all the bitmap */
> - ret = ftruncate(cow_fd, sizeof(cow_header) + ((image_sectors + 7) >> 3));
> + ret = bdrv_truncate(cow_bs,
> + sizeof(cow_header) + ((image_sectors + 7) >> 3));
> if (ret) {
> ret = -errno;
Same here.
> goto exit;
> }
>
> exit:
> - close(cow_fd);
> + bdrv_close(cow_bs);
> return ret;
> }
This should be bdrv_delete.
Kevin
