From bf2bbe07f13846a90d4447521d87566d6f87bc0e Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Fri, 15 Mar 2013 10:55:41 +0000 Subject: xen/events: Add the hypervisor interface for the FIFO-based event channels Add the hypercall sub-ops and the structures for the shared data used in the FIFO-based event channel ABI. The design document for this new ABI is available here: http://xenbits.xen.org/people/dvrabel/event-channels-H.pdf In summary, events are reported using a per-domain shared event array of event words. Each event word has PENDING, LINKED and MASKED bits and a LINK field for pointing to the next event in the event queue. There are 16 event queues (with different priorities) per-VCPU. Key advantages of this new ABI include: - Support for over 100,000 events (2^17). - 16 different event priorities. - Improved fairness in event latency through the use of FIFOs. The ABI is available in Xen 4.4 and later. Signed-off-by: David Vrabel Reviewed-by: Konrad Rzeszutek Wilk Reviewed-by: Boris Ostrovsky --- include/xen/interface/event_channel.h | 68 +++++++++++++++++++++++++++++++++++ include/xen/interface/xen.h | 6 ---- 2 files changed, 68 insertions(+), 6 deletions(-) (limited to 'include/xen/interface') diff --git a/include/xen/interface/event_channel.h b/include/xen/interface/event_channel.h index f4942921e202..7e6acef5415b 100644 --- a/include/xen/interface/event_channel.h +++ b/include/xen/interface/event_channel.h @@ -190,6 +190,39 @@ struct evtchn_reset { }; typedef struct evtchn_reset evtchn_reset_t; +/* + * EVTCHNOP_init_control: initialize the control block for the FIFO ABI. + */ +#define EVTCHNOP_init_control 11 +struct evtchn_init_control { + /* IN parameters. */ + uint64_t control_gfn; + uint32_t offset; + uint32_t vcpu; + /* OUT parameters. */ + uint8_t link_bits; + uint8_t _pad[7]; +}; + +/* + * EVTCHNOP_expand_array: add an additional page to the event array. + */ +#define EVTCHNOP_expand_array 12 +struct evtchn_expand_array { + /* IN parameters. */ + uint64_t array_gfn; +}; + +/* + * EVTCHNOP_set_priority: set the priority for an event channel. + */ +#define EVTCHNOP_set_priority 13 +struct evtchn_set_priority { + /* IN parameters. */ + uint32_t port; + uint32_t priority; +}; + struct evtchn_op { uint32_t cmd; /* EVTCHNOP_* */ union { @@ -207,4 +240,39 @@ struct evtchn_op { }; DEFINE_GUEST_HANDLE_STRUCT(evtchn_op); +/* + * 2-level ABI + */ + +#define EVTCHN_2L_NR_CHANNELS (sizeof(xen_ulong_t) * sizeof(xen_ulong_t) * 64) + +/* + * FIFO ABI + */ + +/* Events may have priorities from 0 (highest) to 15 (lowest). */ +#define EVTCHN_FIFO_PRIORITY_MAX 0 +#define EVTCHN_FIFO_PRIORITY_DEFAULT 7 +#define EVTCHN_FIFO_PRIORITY_MIN 15 + +#define EVTCHN_FIFO_MAX_QUEUES (EVTCHN_FIFO_PRIORITY_MIN + 1) + +typedef uint32_t event_word_t; + +#define EVTCHN_FIFO_PENDING 31 +#define EVTCHN_FIFO_MASKED 30 +#define EVTCHN_FIFO_LINKED 29 +#define EVTCHN_FIFO_BUSY 28 + +#define EVTCHN_FIFO_LINK_BITS 17 +#define EVTCHN_FIFO_LINK_MASK ((1 << EVTCHN_FIFO_LINK_BITS) - 1) + +#define EVTCHN_FIFO_NR_CHANNELS (1 << EVTCHN_FIFO_LINK_BITS) + +struct evtchn_fifo_control_block { + uint32_t ready; + uint32_t _rsvd; + event_word_t head[EVTCHN_FIFO_MAX_QUEUES]; +}; + #endif /* __XEN_PUBLIC_EVENT_CHANNEL_H__ */ diff --git a/include/xen/interface/xen.h b/include/xen/interface/xen.h index 53ec4167bd0b..0cd5ca333fac 100644 --- a/include/xen/interface/xen.h +++ b/include/xen/interface/xen.h @@ -281,12 +281,6 @@ struct multicall_entry { }; DEFINE_GUEST_HANDLE_STRUCT(multicall_entry); -/* - * Event channel endpoints per domain: - * 1024 if a long is 32 bits; 4096 if a long is 64 bits. - */ -#define NR_EVENT_CHANNELS (sizeof(xen_ulong_t) * sizeof(xen_ulong_t) * 64) - struct vcpu_time_info { /* * Updates to the following values are preceded and followed -- cgit v1.2.3 From 4e903a20da51ed2329c1b9c182dba74f47ac2ca8 Mon Sep 17 00:00:00 2001 From: Mukesh Rathor Date: Tue, 31 Dec 2013 11:16:25 -0500 Subject: xen/pvh: Support ParaVirtualized Hardware extensions (v3). PVH allows PV linux guest to utilize hardware extended capabilities, such as running MMU updates in a HVM container. The Xen side defines PVH as (from docs/misc/pvh-readme.txt, with modifications): "* the guest uses auto translate: - p2m is managed by Xen - pagetables are owned by the guest - mmu_update hypercall not available * it uses event callback and not vlapic emulation, * IDT is native, so set_trap_table hcall is also N/A for a PVH guest. For a full list of hcalls supported for PVH, see pvh_hypercall64_table in arch/x86/hvm/hvm.c in xen. From the ABI prespective, it's mostly a PV guest with auto translate, although it does use hvm_op for setting callback vector." Use .ascii and .asciz to define xen feature string. Note, the PVH string must be in a single line (not multiple lines with \) to keep the assembler from putting null char after each string before \. This patch allows it to be configured and enabled. We also use introduce the 'XEN_ELFNOTE_SUPPORTED_FEATURES' ELF note to tell the hypervisor that 'hvm_callback_vector' is what the kernel needs. We can not put it in 'XEN_ELFNOTE_FEATURES' as older hypervisor parse fields they don't understand as errors and refuse to load the kernel. This work-around fixes the problem. Signed-off-by: Mukesh Rathor Signed-off-by: Konrad Rzeszutek Wilk Acked-by: Stefano Stabellini --- include/xen/interface/elfnote.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include/xen/interface') diff --git a/include/xen/interface/elfnote.h b/include/xen/interface/elfnote.h index 0360b15f4883..6f4eae328ca7 100644 --- a/include/xen/interface/elfnote.h +++ b/include/xen/interface/elfnote.h @@ -140,6 +140,19 @@ */ #define XEN_ELFNOTE_SUSPEND_CANCEL 14 +/* + * The features supported by this kernel (numeric). + * + * Other than XEN_ELFNOTE_FEATURES on pre-4.2 Xen, this note allows a + * kernel to specify support for features that older hypervisors don't + * know about. The set of features 4.2 and newer hypervisors will + * consider supported by the kernel is the combination of the sets + * specified through this and the string note. + * + * LEGACY: FEATURES + */ +#define XEN_ELFNOTE_SUPPORTED_FEATURES 17 + #endif /* __XEN_PUBLIC_ELFNOTE_H__ */ /* -- cgit v1.2.3