Mailing List Archive

From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>

This patch continues to make some preparation to x86/hvm/ioreq.c
before moving to the common code.

Add IOREQ_STATUS_* #define-s and update candidates for moving
since X86EMUL_* shouldn't be exposed to the common code in
that form.

This support is going to be used on Arm to be able run device
emulator outside of Xen hypervisor.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
CC: Julien Grall <julien.grall@arm.com>
[On Arm only]
Tested-by: Wei Chen <Wei.Chen@arm.com>

---
Please note, this is a split/cleanup/hardening of Julien's PoC:
"Add support for Guest IO forwarding to a device emulator"

Changes V2 -> V3:
- new patch, was split from
[PATCH V2 01/23] x86/ioreq: Prepare IOREQ feature for making it common

Changes V3 -> V4:
- add Alex's R-b and Jan's A-b
- add a comment above IOREQ_STATUS_* #define-s
---
xen/arch/x86/hvm/ioreq.c | 16 ++++++++--------
xen/include/asm-x86/hvm/ioreq.h | 5 +++++
2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/xen/arch/x86/hvm/ioreq.c b/xen/arch/x86/hvm/ioreq.c
index 468fe84..ff9a546 100644
--- a/xen/arch/x86/hvm/ioreq.c
+++ b/xen/arch/x86/hvm/ioreq.c
@@ -1405,7 +1405,7 @@ static int hvm_send_buffered_ioreq(struct hvm_ioreq_server *s, ioreq_t *p)
pg = iorp->va;

if ( !pg )
- return X86EMUL_UNHANDLEABLE;
+ return IOREQ_STATUS_UNHANDLED;

/*
* Return 0 for the cases we can't deal with:
@@ -1435,7 +1435,7 @@ static int hvm_send_buffered_ioreq(struct hvm_ioreq_server *s, ioreq_t *p)
break;
default:
gdprintk(XENLOG_WARNING, "unexpected ioreq size: %u\n", p->size);
- return X86EMUL_UNHANDLEABLE;
+ return IOREQ_STATUS_UNHANDLED;
}

spin_lock(&s->bufioreq_lock);
@@ -1445,7 +1445,7 @@ static int hvm_send_buffered_ioreq(struct hvm_ioreq_server *s, ioreq_t *p)
{
/* The queue is full: send the iopacket through the normal path. */
spin_unlock(&s->bufioreq_lock);
- return X86EMUL_UNHANDLEABLE;
+ return IOREQ_STATUS_UNHANDLED;
}

pg->buf_ioreq[pg->ptrs.write_pointer % IOREQ_BUFFER_SLOT_NUM] = bp;
@@ -1476,7 +1476,7 @@ static int hvm_send_buffered_ioreq(struct hvm_ioreq_server *s, ioreq_t *p)
notify_via_xen_event_channel(d, s->bufioreq_evtchn);
spin_unlock(&s->bufioreq_lock);

- return X86EMUL_OKAY;
+ return IOREQ_STATUS_HANDLED;
}

int hvm_send_ioreq(struct hvm_ioreq_server *s, ioreq_t *proto_p,
@@ -1492,7 +1492,7 @@ int hvm_send_ioreq(struct hvm_ioreq_server *s, ioreq_t *proto_p,
return hvm_send_buffered_ioreq(s, proto_p);

if ( unlikely(!vcpu_start_shutdown_deferral(curr)) )
- return X86EMUL_RETRY;
+ return IOREQ_STATUS_RETRY;

list_for_each_entry ( sv,
&s->ioreq_vcpu_list,
@@ -1532,11 +1532,11 @@ int hvm_send_ioreq(struct hvm_ioreq_server *s, ioreq_t *proto_p,
notify_via_xen_event_channel(d, port);

sv->pending = true;
- return X86EMUL_RETRY;
+ return IOREQ_STATUS_RETRY;
}
}

- return X86EMUL_UNHANDLEABLE;
+ return IOREQ_STATUS_UNHANDLED;
}

unsigned int hvm_broadcast_ioreq(ioreq_t *p, bool buffered)
@@ -1550,7 +1550,7 @@ unsigned int hvm_broadcast_ioreq(ioreq_t *p, bool buffered)
if ( !s->enabled )
continue;

- if ( hvm_send_ioreq(s, p, buffered) == X86EMUL_UNHANDLEABLE )
+ if ( hvm_send_ioreq(s, p, buffered) == IOREQ_STATUS_UNHANDLED )
failed++;
}

diff --git a/xen/include/asm-x86/hvm/ioreq.h b/xen/include/asm-x86/hvm/ioreq.h
index 13d35e1..f140ef4 100644
--- a/xen/include/asm-x86/hvm/ioreq.h
+++ b/xen/include/asm-x86/hvm/ioreq.h
@@ -77,6 +77,11 @@ bool arch_ioreq_server_get_type_addr(const struct domain *d,
uint64_t *addr);
void arch_ioreq_domain_init(struct domain *d);

+/* This correlation must not be altered */
+#define IOREQ_STATUS_HANDLED X86EMUL_OKAY
+#define IOREQ_STATUS_UNHANDLED X86EMUL_UNHANDLEABLE
+#define IOREQ_STATUS_RETRY X86EMUL_RETRY
+
#endif /* __ASM_X86_HVM_IOREQ_H__ */

/*
--
2.7.4