[PATCH net-next v5 0/4] vsock: Introduce SIOCINQ ioctl support

[Xuewei Niu]

Introduce SIOCINQ ioctl support for vsock, indicating the length of unread
bytes.

Similar with SIOCOUTQ ioctl, the information is transport-dependent.

The first patch adds SIOCINQ ioctl support in AF_VSOCK.

Thanks to @dexuan, the second patch is to fix the issue where hyper-v
`hvs_stream_has_data()` doesn't return the readable bytes.

The third patch wraps the ioctl into `ioctl_int()`, which implements a
retry mechanism to prevent immediate failure.

The last one adds two test cases to check the functionality. The changes
have been tested, and the results are as expected.

Signed-off-by: Xuewei Niu <niuxuewei.nxw@xxxxxxxxxxxx>

--

v1->v2:
https://lore.kernel.org/lkml/20250519070649.3063874-1-niuxuewei.nxw@xxxxxxxxxxxx/
- Use net-next tree.
- Reuse `rx_bytes` to count unread bytes.
- Wrap ioctl syscall with an int pointer argument to implement a retry
  mechanism.

v2->v3:
https://lore.kernel.org/netdev/20250613031152.1076725-1-niuxuewei.nxw@xxxxxxxxxxxx/
- Update commit messages following the guidelines
- Remove `unread_bytes` callback and reuse `vsock_stream_has_data()`
- Move the tests to the end of array
- Split the refactoring patch
- Include <sys/ioctl.h> in the util.c

v3->v4:
https://lore.kernel.org/netdev/20250617045347.1233128-1-niuxuewei.nxw@xxxxxxxxxxxx/
- Hyper-v `hvs_stream_has_data()` returns the readable bytes
- Skip testing the null value for `actual` (int pointer)
- Rename `ioctl_int()` to `vsock_ioctl_int()`
- Fix a typo and a format issue in comments
- Remove the `RECEIVED` barrier.
- The return type of `vsock_ioctl_int()` has been changed to bool

v4->v5:
https://lore.kernel.org/netdev/20250630075727.210462-1-niuxuewei.nxw@xxxxxxxxxxxx/
- Put the hyper-v fix before the SIOCINQ ioctl implementation.
- Remove my SOB from the hyper-v fix patch.
- Move the `need_refill` initialization into the `case 1` block.
- Remove the `actual` argument from `vsock_ioctl_int()`.
- Replace `TIOCINQ` with `SIOCINQ`.

---
Xuewei Niu (4):
      hv_sock: Return the readable bytes in hvs_stream_has_data()
      vsock: Add support for SIOCINQ ioctl
      test/vsock: Add retry mechanism to ioctl wrapper
      test/vsock: Add ioctl SIOCINQ tests

 net/vmw_vsock/af_vsock.c         | 22 +++++++++++
 net/vmw_vsock/hyperv_transport.c | 17 +++++++--
 tools/testing/vsock/util.c       | 30 ++++++++++-----
 tools/testing/vsock/util.h       |  1 +
 tools/testing/vsock/vsock_test.c | 79 ++++++++++++++++++++++++++++++++++++++++
 5 files changed, 137 insertions(+), 12 deletions(-)
---
base-commit: 5f712c3877f99d5b5e4d011955c6467ae0e535a6
change-id: 20250703-siocinq-9e2907939806

Best regards,
-- 
Xuewei Niu <niuxuewei.nxw@xxxxxxxxxxxx>