hmp: Request permissions in qemu-io

The HMP command 'qemu-io' is a bit tricky because it wants to work on
the original BlockBackend, but additional permissions could be required.
The details are explained in a comment in the code, but in summary, just
request whatever permissions the current qemu-io command needs.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
This commit is contained in:
Kevin Wolf 2017-02-10 16:24:56 +01:00
parent 0db832f42e
commit 887354bd13
5 changed files with 61 additions and 1 deletions

View file

@ -83,6 +83,29 @@ static int command(BlockBackend *blk, const cmdinfo_t *ct, int argc,
}
return 0;
}
/* Request additional permissions if necessary for this command. The caller
* is responsible for restoring the original permissions afterwards if this
* is what it wants. */
if (ct->perm && blk_is_available(blk)) {
uint64_t orig_perm, orig_shared_perm;
blk_get_perm(blk, &orig_perm, &orig_shared_perm);
if (ct->perm & ~orig_perm) {
uint64_t new_perm;
Error *local_err = NULL;
int ret;
new_perm = orig_perm | ct->perm;
ret = blk_set_perm(blk, new_perm, orig_shared_perm, &local_err);
if (ret < 0) {
error_report_err(local_err);
return 0;
}
}
}
optind = 0;
return ct->cfunc(blk, argc, argv);
}
@ -918,6 +941,7 @@ static const cmdinfo_t write_cmd = {
.name = "write",
.altname = "w",
.cfunc = write_f,
.perm = BLK_PERM_WRITE,
.argmin = 2,
.argmax = -1,
.args = "[-bcCfquz] [-P pattern] off len",
@ -1093,6 +1117,7 @@ static int writev_f(BlockBackend *blk, int argc, char **argv);
static const cmdinfo_t writev_cmd = {
.name = "writev",
.cfunc = writev_f,
.perm = BLK_PERM_WRITE,
.argmin = 2,
.argmax = -1,
.args = "[-Cfq] [-P pattern] off len [len..]",
@ -1392,6 +1417,7 @@ static int aio_write_f(BlockBackend *blk, int argc, char **argv);
static const cmdinfo_t aio_write_cmd = {
.name = "aio_write",
.cfunc = aio_write_f,
.perm = BLK_PERM_WRITE,
.argmin = 2,
.argmax = -1,
.args = "[-Cfiquz] [-P pattern] off len [len..]",
@ -1556,6 +1582,7 @@ static const cmdinfo_t truncate_cmd = {
.name = "truncate",
.altname = "t",
.cfunc = truncate_f,
.perm = BLK_PERM_WRITE | BLK_PERM_RESIZE,
.argmin = 1,
.argmax = 1,
.args = "off",
@ -1653,6 +1680,7 @@ static const cmdinfo_t discard_cmd = {
.name = "discard",
.altname = "d",
.cfunc = discard_f,
.perm = BLK_PERM_WRITE,
.argmin = 2,
.argmax = -1,
.args = "[-Cq] off len",