qcow: Use bdrv functions to replace file operation

Since common file operation functions lack of error detection and use
much more I/O syscalls, so change them to bdrv series functions and
reduce I/O request.

Signed-off-by: Li Zhi Hui <zhihuili@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Li Zhi Hui 2011-11-21 15:40:39 +08:00 committed by Kevin Wolf
parent 84b0ec020f
commit 2b16c9ffb2

View File

@ -644,13 +644,14 @@ static void qcow_close(BlockDriverState *bs)
static int qcow_create(const char *filename, QEMUOptionParameter *options)
{
int fd, header_size, backing_filename_len, l1_size, i, shift;
int header_size, backing_filename_len, l1_size, shift, i;
QCowHeader header;
uint64_t tmp;
uint8_t *tmp;
int64_t total_size = 0;
const char *backing_file = NULL;
int flags = 0;
int ret;
BlockDriverState *qcow_bs;
/* Read out options */
while (options && options->name) {
@ -664,9 +665,21 @@ static int qcow_create(const char *filename, QEMUOptionParameter *options)
options++;
}
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
if (fd < 0)
return -errno;
ret = bdrv_create_file(filename, options);
if (ret < 0) {
return ret;
}
ret = bdrv_file_open(&qcow_bs, filename, BDRV_O_RDWR);
if (ret < 0) {
return ret;
}
ret = bdrv_truncate(qcow_bs, 0);
if (ret < 0) {
goto exit;
}
memset(&header, 0, sizeof(header));
header.magic = cpu_to_be32(QCOW_MAGIC);
header.version = cpu_to_be32(QCOW_VERSION);
@ -702,33 +715,34 @@ static int qcow_create(const char *filename, QEMUOptionParameter *options)
}
/* write all the data */
ret = qemu_write_full(fd, &header, sizeof(header));
ret = bdrv_pwrite(qcow_bs, 0, &header, sizeof(header));
if (ret != sizeof(header)) {
ret = -errno;
goto exit;
}
if (backing_file) {
ret = qemu_write_full(fd, backing_file, backing_filename_len);
ret = bdrv_pwrite(qcow_bs, sizeof(header),
backing_file, backing_filename_len);
if (ret != backing_filename_len) {
ret = -errno;
goto exit;
}
}
lseek(fd, header_size, SEEK_SET);
tmp = 0;
for(i = 0;i < l1_size; i++) {
ret = qemu_write_full(fd, &tmp, sizeof(tmp));
if (ret != sizeof(tmp)) {
ret = -errno;
goto exit;
}
}
tmp = g_malloc0(BDRV_SECTOR_SIZE);
for (i = 0; i < ((sizeof(uint64_t)*l1_size + BDRV_SECTOR_SIZE - 1)/
BDRV_SECTOR_SIZE); i++) {
ret = bdrv_pwrite(qcow_bs, header_size +
BDRV_SECTOR_SIZE*i, tmp, BDRV_SECTOR_SIZE);
if (ret != BDRV_SECTOR_SIZE) {
g_free(tmp);
goto exit;
}
}
g_free(tmp);
ret = 0;
exit:
close(fd);
bdrv_delete(qcow_bs);
return ret;
}