qemu-io: Switch to byte-based block access

qemu-io is the last user of several sector-based interfaces.
This patch upgrades to the new interfaces under the hood,
then deletes the resulting dead code.  Note that for maximum
back-compat, while the -p option is no longer required to get
blk_pread(), it is still needed to allow for unaligned access;
this is because qemu-iotest 23 relies on qemu-io rejecting
unaligned accesses without -p.  A later patch may clean up the
interface to be more user-friendly, but it's better to separate
what's done under the hood from what the user sees.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Eric Blake 2016-05-06 10:26:44 -06:00 committed by Kevin Wolf
parent 9166920a0b
commit 7b3f9712e1

View File

@ -419,40 +419,6 @@ fail:
return buf;
}
static int do_read(BlockBackend *blk, char *buf, int64_t offset, int64_t count,
int64_t *total)
{
int ret;
if (count >> 9 > INT_MAX) {
return -ERANGE;
}
ret = blk_read(blk, offset >> 9, (uint8_t *)buf, count >> 9);
if (ret < 0) {
return ret;
}
*total = count;
return 1;
}
static int do_write(BlockBackend *blk, char *buf, int64_t offset, int64_t count,
int64_t *total)
{
int ret;
if (count >> 9 > INT_MAX) {
return -ERANGE;
}
ret = blk_write(blk, offset >> 9, (uint8_t *)buf, count >> 9);
if (ret < 0) {
return ret;
}
*total = count;
return 1;
}
static int do_pread(BlockBackend *blk, char *buf, int64_t offset,
int64_t count, int64_t *total)
{
@ -588,8 +554,7 @@ static int do_aio_readv(BlockBackend *blk, QEMUIOVector *qiov,
{
int async_ret = NOT_DONE;
blk_aio_readv(blk, offset >> 9, qiov, qiov->size >> 9,
aio_rw_done, &async_ret);
blk_aio_preadv(blk, offset, qiov, 0, aio_rw_done, &async_ret);
while (async_ret == NOT_DONE) {
main_loop_wait(false);
}
@ -603,8 +568,7 @@ static int do_aio_writev(BlockBackend *blk, QEMUIOVector *qiov,
{
int async_ret = NOT_DONE;
blk_aio_writev(blk, offset >> 9, qiov, qiov->size >> 9,
aio_rw_done, &async_ret);
blk_aio_pwritev(blk, offset, qiov, 0, aio_rw_done, &async_ret);
while (async_ret == NOT_DONE) {
main_loop_wait(false);
}
@ -670,7 +634,7 @@ static void read_help(void)
" -b, -- read from the VM state rather than the virtual disk\n"
" -C, -- report statistics in a machine parsable format\n"
" -l, -- length for pattern verification (only with -P)\n"
" -p, -- use blk_pread to read the file\n"
" -p, -- allow unaligned access\n"
" -P, -- use a pattern to verify read data\n"
" -q, -- quiet mode, do not show I/O statistics\n"
" -s, -- start offset for pattern verification (only with -P)\n"
@ -805,12 +769,10 @@ static int read_f(BlockBackend *blk, int argc, char **argv)
buf = qemu_io_alloc(blk, count, 0xab);
gettimeofday(&t1, NULL);
if (pflag) {
cnt = do_pread(blk, buf, offset, count, &total);
} else if (bflag) {
if (bflag) {
cnt = do_load_vmstate(blk, buf, offset, count, &total);
} else {
cnt = do_read(blk, buf, offset, count, &total);
cnt = do_pread(blk, buf, offset, count, &total);
}
gettimeofday(&t2, NULL);
@ -990,7 +952,7 @@ static void write_help(void)
" filled with a set pattern (0xcdcdcdcd).\n"
" -b, -- write to the VM state rather than the virtual disk\n"
" -c, -- write compressed data with blk_write_compressed\n"
" -p, -- use blk_pwrite to write the file\n"
" -p, -- allow unaligned access\n"
" -P, -- use different pattern to fill file\n"
" -C, -- report statistics in a machine parsable format\n"
" -q, -- quiet mode, do not show I/O statistics\n"
@ -1106,16 +1068,14 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
}
gettimeofday(&t1, NULL);
if (pflag) {
cnt = do_pwrite(blk, buf, offset, count, &total);
} else if (bflag) {
if (bflag) {
cnt = do_save_vmstate(blk, buf, offset, count, &total);
} else if (zflag) {
cnt = do_co_write_zeroes(blk, offset, count, &total);
} else if (cflag) {
cnt = do_write_compressed(blk, buf, offset, count, &total);
} else {
cnt = do_write(blk, buf, offset, count, &total);
cnt = do_pwrite(blk, buf, offset, count, &total);
}
gettimeofday(&t2, NULL);
@ -1592,8 +1552,7 @@ static int aio_read_f(BlockBackend *blk, int argc, char **argv)
gettimeofday(&ctx->t1, NULL);
block_acct_start(blk_get_stats(blk), &ctx->acct, ctx->qiov.size,
BLOCK_ACCT_READ);
blk_aio_readv(blk, ctx->offset >> 9, &ctx->qiov,
ctx->qiov.size >> 9, aio_read_done, ctx);
blk_aio_preadv(blk, ctx->offset, &ctx->qiov, 0, aio_read_done, ctx);
return 0;
}
@ -1718,8 +1677,7 @@ static int aio_write_f(BlockBackend *blk, int argc, char **argv)
block_acct_start(blk_get_stats(blk), &ctx->acct, ctx->qiov.size,
BLOCK_ACCT_WRITE);
blk_aio_writev(blk, ctx->offset >> 9, &ctx->qiov,
ctx->qiov.size >> 9, aio_write_done, ctx);
blk_aio_pwritev(blk, ctx->offset, &ctx->qiov, 0, aio_write_done, ctx);
}
return 0;
}