};
typedef struct BDRVCowState {
- int fd;
+ CoMutex lock;
int64_t cow_sectors_offset;
} BDRVCowState;
return 0;
}
-static int cow_open(BlockDriverState *bs, const char *filename, int flags)
+static int cow_open(BlockDriverState *bs, int flags)
{
BDRVCowState *s = bs->opaque;
- int fd;
struct cow_header_v2 cow_header;
int bitmap_size;
int64_t size;
+ int ret;
- fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE);
- if (fd < 0) {
- fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
- if (fd < 0)
- return -1;
- }
- s->fd = fd;
/* see if it is a cow image */
- if (pread(fd, &cow_header, sizeof(cow_header), 0) != sizeof(cow_header)) {
+ ret = bdrv_pread(bs->file, 0, &cow_header, sizeof(cow_header));
+ if (ret < 0) {
+ goto fail;
+ }
+
+ if (be32_to_cpu(cow_header.magic) != COW_MAGIC) {
+ ret = -EINVAL;
goto fail;
}
- if (be32_to_cpu(cow_header.magic) != COW_MAGIC ||
- be32_to_cpu(cow_header.version) != COW_VERSION) {
+ if (be32_to_cpu(cow_header.version) != COW_VERSION) {
+ char version[64];
+ snprintf(version, sizeof(version),
+ "COW version %d", cow_header.version);
+ qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
+ bs->device_name, "cow", version);
+ ret = -ENOTSUP;
goto fail;
}
bitmap_size = ((bs->total_sectors + 7) >> 3) + sizeof(cow_header);
s->cow_sectors_offset = (bitmap_size + 511) & ~511;
+ qemu_co_mutex_init(&s->lock);
return 0;
fail:
- close(fd);
- return -1;
+ return ret;
}
/*
- * XXX(hch): right now these functions are extremly ineffcient.
+ * XXX(hch): right now these functions are extremely ineffcient.
* We should just read the whole bitmap we'll need in one go instead.
*/
static inline int cow_set_bit(BlockDriverState *bs, int64_t bitnum)
{
- BDRVCowState *s = bs->opaque;
uint64_t offset = sizeof(struct cow_header_v2) + bitnum / 8;
uint8_t bitmap;
+ int ret;
- if (pread(s->fd, &bitmap, sizeof(bitmap), offset) !=
- sizeof(bitmap)) {
- return -errno;
+ ret = bdrv_pread(bs->file, offset, &bitmap, sizeof(bitmap));
+ if (ret < 0) {
+ return ret;
}
bitmap |= (1 << (bitnum % 8));
- if (pwrite(s->fd, &bitmap, sizeof(bitmap), offset) !=
- sizeof(bitmap)) {
- return -errno;
+ ret = bdrv_pwrite_sync(bs->file, offset, &bitmap, sizeof(bitmap));
+ if (ret < 0) {
+ return ret;
}
return 0;
}
static inline int is_bit_set(BlockDriverState *bs, int64_t bitnum)
{
- BDRVCowState *s = bs->opaque;
uint64_t offset = sizeof(struct cow_header_v2) + bitnum / 8;
uint8_t bitmap;
+ int ret;
- if (pread(s->fd, &bitmap, sizeof(bitmap), offset) !=
- sizeof(bitmap)) {
- return -errno;
+ ret = bdrv_pread(bs->file, offset, &bitmap, sizeof(bitmap));
+ if (ret < 0) {
+ return ret;
}
return !!(bitmap & (1 << (bitnum % 8)));
/* Return true if first block has been changed (ie. current version is
* in COW file). Set the number of continuous blocks for which that
* is true. */
-static int cow_is_allocated(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, int *num_same)
+static int coroutine_fn cow_co_is_allocated(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, int *num_same)
{
int changed;
return error;
}
-static int cow_read(BlockDriverState *bs, int64_t sector_num,
- uint8_t *buf, int nb_sectors)
+static int coroutine_fn cow_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
{
BDRVCowState *s = bs->opaque;
int ret, n;
while (nb_sectors > 0) {
- if (cow_is_allocated(bs, sector_num, nb_sectors, &n)) {
- ret = pread(s->fd, buf, n * 512,
- s->cow_sectors_offset + sector_num * 512);
- if (ret != n * 512)
- return -1;
+ if (bdrv_co_is_allocated(bs, sector_num, nb_sectors, &n)) {
+ ret = bdrv_pread(bs->file,
+ s->cow_sectors_offset + sector_num * 512,
+ buf, n * 512);
+ if (ret < 0) {
+ return ret;
+ }
} else {
if (bs->backing_hd) {
/* read from the base image */
ret = bdrv_read(bs->backing_hd, sector_num, buf, n);
- if (ret < 0)
- return -1;
+ if (ret < 0) {
+ return ret;
+ }
} else {
- memset(buf, 0, n * 512);
- }
+ memset(buf, 0, n * 512);
+ }
}
nb_sectors -= n;
sector_num += n;
return 0;
}
+static coroutine_fn int cow_co_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ int ret;
+ BDRVCowState *s = bs->opaque;
+ qemu_co_mutex_lock(&s->lock);
+ ret = cow_read(bs, sector_num, buf, nb_sectors);
+ qemu_co_mutex_unlock(&s->lock);
+ return ret;
+}
+
static int cow_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
BDRVCowState *s = bs->opaque;
int ret;
- ret = pwrite(s->fd, buf, nb_sectors * 512,
- s->cow_sectors_offset + sector_num * 512);
- if (ret != nb_sectors * 512)
- return -1;
+ ret = bdrv_pwrite(bs->file, s->cow_sectors_offset + sector_num * 512,
+ buf, nb_sectors * 512);
+ if (ret < 0) {
+ return ret;
+ }
return cow_update_bitmap(bs, sector_num, nb_sectors);
}
-static void cow_close(BlockDriverState *bs)
+static coroutine_fn int cow_co_write(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t *buf, int nb_sectors)
{
+ int ret;
BDRVCowState *s = bs->opaque;
- close(s->fd);
+ qemu_co_mutex_lock(&s->lock);
+ ret = cow_write(bs, sector_num, buf, nb_sectors);
+ qemu_co_mutex_unlock(&s->lock);
+ return ret;
+}
+
+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;
/* Read out options */
while (options && options->name) {
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);
/* 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);
- goto mtime_fail;
- }
- if (fstat(fd, &st) != 0) {
- close(fd);
+ if (stat(image_filename, &st) != 0) {
goto mtime_fail;
}
- close(fd);
cow_header.mtime = cpu_to_be32(st.st_mtime);
mtime_fail:
pstrcpy(cow_header.backing_file, sizeof(cow_header.backing_file),
}
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));
- if (ret != sizeof(cow_header)) {
- ret = -errno;
+ ret = bdrv_pwrite(cow_bs, 0, &cow_header, sizeof(cow_header));
+ if (ret < 0) {
goto exit;
}
/* resize to include at least all the bitmap */
- ret = ftruncate(cow_fd, sizeof(cow_header) + ((image_sectors + 7) >> 3));
- if (ret) {
- ret = -errno;
+ ret = bdrv_truncate(cow_bs,
+ sizeof(cow_header) + ((image_sectors + 7) >> 3));
+ if (ret < 0) {
goto exit;
}
exit:
- close(cow_fd);
+ bdrv_delete(cow_bs);
return ret;
}
-static void cow_flush(BlockDriverState *bs)
+static coroutine_fn int cow_co_flush(BlockDriverState *bs)
{
- BDRVCowState *s = bs->opaque;
- qemu_fdatasync(s->fd);
+ return bdrv_co_flush(bs->file);
}
static QEMUOptionParameter cow_create_options[] = {
};
static BlockDriver bdrv_cow = {
- .format_name = "cow",
- .instance_size = sizeof(BDRVCowState),
- .bdrv_probe = cow_probe,
- .bdrv_file_open = cow_open,
- .bdrv_read = cow_read,
- .bdrv_write = cow_write,
- .bdrv_close = cow_close,
- .bdrv_create = cow_create,
- .bdrv_flush = cow_flush,
- .bdrv_is_allocated = cow_is_allocated,
+ .format_name = "cow",
+ .instance_size = sizeof(BDRVCowState),
+
+ .bdrv_probe = cow_probe,
+ .bdrv_open = cow_open,
+ .bdrv_close = cow_close,
+ .bdrv_create = cow_create,
+
+ .bdrv_read = cow_co_read,
+ .bdrv_write = cow_co_write,
+ .bdrv_co_flush_to_disk = cow_co_flush,
+ .bdrv_co_is_allocated = cow_co_is_allocated,
.create_options = cow_create_options,
};
projects / qemu.git / blobdiff