Ack all 3 patches
On Wed, Jan 22, 2025 at 5:56 PM Liu Kui <kui....@virtuozzo.com> wrote:
>
> Currently if a msg is completed in error, the error is not properly
> returned to userspace making userspace unable to process such error
> correctly. Thus userspace has to abort the connection whenever there's
> a msg completing in error. Even non-fatal error such as the response
> timeout error would result in abortion of the connecion, which is just
> a wrong behaivor.
>
> By passing the response timeout error to userspace, it allows userspace
> to solely rely on the kill timer in kernel rpc for waiting for response.
> Acting this way can remove the possibility that a userpsace request is
> completed before its corresponding request completes in kernel space,
> thus addressing two issues that could otherwise happen, 1) userspace
> receives a stale response from kernel. 2) kernel access buffs that have
> been released in userspace.
>
> Related to #VSTOR-97762
> Signed-off-by: Liu Kui <kui....@virtuozzo.com>
> ---
> fs/fuse/kio/pcs/pcs_krpc.c | 10 +++-------
> fs/fuse/kio/pcs/pcs_krpc_prot.h | 10 +++++++---
> 2 files changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/fs/fuse/kio/pcs/pcs_krpc.c b/fs/fuse/kio/pcs/pcs_krpc.c
> index 45ec3cb3207c..2ab1450a0005 100644
> --- a/fs/fuse/kio/pcs/pcs_krpc.c
> +++ b/fs/fuse/kio/pcs/pcs_krpc.c
> @@ -279,21 +279,17 @@ static int pcs_krpc_ioctl_recv_msg(struct pcs_krpc
> *krpc, struct pcs_krpc_ioc_re
> krpc->nr_completion--;
> spin_unlock(&krpc->lock);
>
> - if (comp->result) {
> - res -= comp->result;
> - goto out;
> - }
> -
> res = 1;
> iocmsg->xid = comp->xid;
> - if (comp->xid == 0) {
> + if (comp->xid == 0) { /* request */
> BUG_ON(!comp->data_len);
> BUG_ON(iocmsg->buf.len < comp->data_len);
> if (copy_to_user((void __user *)iocmsg->buf.addr,
> comp->_data_buf, comp->data_len))
> res = -EFAULT;
> + } else { /* response */
> + iocmsg->result = comp->result;
> }
>
> -out:
> krpc_completion_free(comp);
> return res;
> }
> diff --git a/fs/fuse/kio/pcs/pcs_krpc_prot.h b/fs/fuse/kio/pcs/pcs_krpc_prot.h
> index 81caa1d53669..812f778a6a06 100644
> --- a/fs/fuse/kio/pcs/pcs_krpc_prot.h
> +++ b/fs/fuse/kio/pcs/pcs_krpc_prot.h
> @@ -7,8 +7,9 @@
> * kRPC version:
> * v1: Initial krpc support
> * v2: Support zerocopy read
> + * v3: Return error code to userspace
> */
> -#define PCS_KRPC_VERSION 2
> +#define PCS_KRPC_VERSION 3
>
> /* Device ioctls: */
> #define PCS_KRPC_IOC_MAGIC 255
> @@ -50,14 +51,17 @@ struct pcs_krpc_ioc_sendmsg {
> u64 xid; /* context id */
> u32 msg_size; /* total size of the
> msg */
> u16 timeout; /* timeout */
> - u8 flags; /* alignment, */
> + u8 flags; /* alignment */
> u8 nr_data_chunks; /* total number of data
> chunks */
> struct pcs_krpc_buf_desc hdr_chunk; /* the buf holding msg header
> */
> };
>
> struct pcs_krpc_ioc_recvmsg {
> u64 xid; /* context id */
> - struct pcs_krpc_buf_desc buf; /* for cs congestion notification and
> rpc keep waiting msg.*/
> + union {
> + u32 result; /* for response msg */
> + struct pcs_krpc_buf_desc buf; /* for request msg */
> + };
> };
>
> #endif
> --
> 2.39.5 (Apple Git-154)
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