Make it easier to test block drivers with BDRV_REQ_FUA in
.supported_write_flags, by adding a flag to qemu-io to
conditionally pass the flag through to specific writes. You'll
want to use 'qemu-io -t none' to actually make -f useful (as
otherwise, the default writethrough mode automatically sets
the FUA bit on every write).
Signed-off-by: Eric Blake <ebl...@redhat.com>
---
qemu-io-cmds.c | 31 ++++++++++++++++++++++---------
1 file changed, 22 insertions(+), 9 deletions(-)
diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index 4184fb8..1e444cc 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -434,13 +434,14 @@ static int do_pread(BlockBackend *blk, char *buf, int64_t
offset,
}
static int do_pwrite(BlockBackend *blk, char *buf, int64_t offset,
- int64_t count, int64_t *total)
+ int64_t count, bool fua, int64_t *total)
{
if (count > INT_MAX) {
return -ERANGE;
}
- *total = blk_pwrite(blk, offset, (uint8_t *)buf, count, 0);
+ *total = blk_pwrite(blk, offset, (uint8_t *)buf, count,
+ fua ? BDRV_REQ_FUA : 0);
if (*total < 0) {
return *total;
}
@@ -452,6 +453,7 @@ typedef struct {
int64_t offset;
int64_t count;
int64_t *total;
+ bool fua;
int ret;
bool done;
} CoWriteZeroes;
@@ -461,7 +463,8 @@ static void coroutine_fn co_write_zeroes_entry(void *opaque)
CoWriteZeroes *data = opaque;
data->ret = blk_co_write_zeroes(data->blk, data->offset / BDRV_SECTOR_SIZE,
- data->count / BDRV_SECTOR_SIZE, 0);
+ data->count / BDRV_SECTOR_SIZE,
+ data->fua ? BDRV_REQ_FUA : 0);
data->done = true;
if (data->ret < 0) {
*data->total = data->ret;
@@ -472,7 +475,7 @@ static void coroutine_fn co_write_zeroes_entry(void *opaque)
}
static int do_co_write_zeroes(BlockBackend *blk, int64_t offset, int64_t count,
- int64_t *total)
+ bool fua, int64_t *total)
{
Coroutine *co;
CoWriteZeroes data = {
@@ -480,6 +483,7 @@ static int do_co_write_zeroes(BlockBackend *blk, int64_t
offset, int64_t count,
.offset = offset,
.count = count,
.total = total,
+ .fua = fua,
.done = false,
};
@@ -950,6 +954,7 @@ 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"
+" -f, -- use Force Unit Access semantics\n"
" -p, -- ignored for back-compat\n"
" -P, -- use different pattern to fill file\n"
" -C, -- report statistics in a machine parsable format\n"
@@ -966,7 +971,7 @@ static const cmdinfo_t write_cmd = {
.cfunc = write_f,
.argmin = 2,
.argmax = -1,
- .args = "[-bcCqz] [-P pattern ] off len",
+ .args = "[-bcCfqz] [-P pattern ] off len",
.oneline = "writes a number of bytes at a specified offset",
.help = write_help,
};
@@ -975,7 +980,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
{
struct timeval t1, t2;
int Cflag = 0, qflag = 0, bflag = 0, Pflag = 0, zflag = 0;
- int cflag = 0;
+ int cflag = 0, fflag = 0;
int c, cnt;
char *buf = NULL;
int64_t offset;
@@ -984,7 +989,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
int64_t total = 0;
int pattern = 0xcd;
- while ((c = getopt(argc, argv, "bcCpP:qz")) != -1) {
+ while ((c = getopt(argc, argv, "bcCfpP:qz")) != -1) {
switch (c) {
case 'b':
bflag = 1;
@@ -995,6 +1000,9 @@ static int write_f(BlockBackend *blk, int argc, char
**argv)
case 'C':
Cflag = 1;
break;
+ case 'f':
+ fflag = 1;
+ break;
case 'p':
/* Ignored for back-compat */
break;
@@ -1025,6 +1033,11 @@ static int write_f(BlockBackend *blk, int argc, char
**argv)
return 0;
}
+ if (fflag && (bflag + cflag)) {
+ printf("-f and -b or -c cannot be specified at the same time\n");
+ return 0;
+ }
+
if (zflag && Pflag) {
printf("-z and -P cannot be specified at the same time\n");
return 0;
@@ -1069,11 +1082,11 @@ static int write_f(BlockBackend *blk, int argc, char
**argv)
if (bflag) {
cnt = do_save_vmstate(blk, buf, offset, count, &total);
} else if (zflag) {
- cnt = do_co_write_zeroes(blk, offset, count, &total);
+ cnt = do_co_write_zeroes(blk, offset, count, fflag, &total);
} else if (cflag) {
cnt = do_write_compressed(blk, buf, offset, count, &total);
} else {
- cnt = do_pwrite(blk, buf, offset, count, &total);
+ cnt = do_pwrite(blk, buf, offset, count, fflag, &total);
}
gettimeofday(&t2, NULL);
--
2.5.5
