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1942 lines
48 KiB
1942 lines
48 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* Copyright (c) 2012, Microsoft Corporation. |
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* |
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* Author: |
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* K. Y. Srinivasan <[email protected]> |
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*/ |
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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#include <linux/kernel.h> |
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#include <linux/jiffies.h> |
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#include <linux/mman.h> |
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#include <linux/delay.h> |
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#include <linux/init.h> |
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#include <linux/module.h> |
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#include <linux/slab.h> |
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#include <linux/kthread.h> |
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#include <linux/completion.h> |
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#include <linux/memory_hotplug.h> |
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#include <linux/memory.h> |
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#include <linux/notifier.h> |
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#include <linux/percpu_counter.h> |
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#include <linux/page_reporting.h> |
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#include <linux/hyperv.h> |
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#include <asm/hyperv-tlfs.h> |
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#include <asm/mshyperv.h> |
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#define CREATE_TRACE_POINTS |
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#include "hv_trace_balloon.h" |
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/* |
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* We begin with definitions supporting the Dynamic Memory protocol |
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* with the host. |
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* |
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* Begin protocol definitions. |
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*/ |
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/* |
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* Protocol versions. The low word is the minor version, the high word the major |
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* version. |
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* |
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* History: |
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* Initial version 1.0 |
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* Changed to 0.1 on 2009/03/25 |
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* Changes to 0.2 on 2009/05/14 |
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* Changes to 0.3 on 2009/12/03 |
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* Changed to 1.0 on 2011/04/05 |
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*/ |
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#define DYNMEM_MAKE_VERSION(Major, Minor) ((__u32)(((Major) << 16) | (Minor))) |
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#define DYNMEM_MAJOR_VERSION(Version) ((__u32)(Version) >> 16) |
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#define DYNMEM_MINOR_VERSION(Version) ((__u32)(Version) & 0xff) |
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enum { |
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DYNMEM_PROTOCOL_VERSION_1 = DYNMEM_MAKE_VERSION(0, 3), |
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DYNMEM_PROTOCOL_VERSION_2 = DYNMEM_MAKE_VERSION(1, 0), |
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DYNMEM_PROTOCOL_VERSION_3 = DYNMEM_MAKE_VERSION(2, 0), |
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DYNMEM_PROTOCOL_VERSION_WIN7 = DYNMEM_PROTOCOL_VERSION_1, |
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DYNMEM_PROTOCOL_VERSION_WIN8 = DYNMEM_PROTOCOL_VERSION_2, |
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DYNMEM_PROTOCOL_VERSION_WIN10 = DYNMEM_PROTOCOL_VERSION_3, |
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DYNMEM_PROTOCOL_VERSION_CURRENT = DYNMEM_PROTOCOL_VERSION_WIN10 |
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}; |
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/* |
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* Message Types |
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*/ |
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enum dm_message_type { |
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/* |
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* Version 0.3 |
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*/ |
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DM_ERROR = 0, |
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DM_VERSION_REQUEST = 1, |
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DM_VERSION_RESPONSE = 2, |
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DM_CAPABILITIES_REPORT = 3, |
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DM_CAPABILITIES_RESPONSE = 4, |
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DM_STATUS_REPORT = 5, |
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DM_BALLOON_REQUEST = 6, |
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DM_BALLOON_RESPONSE = 7, |
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DM_UNBALLOON_REQUEST = 8, |
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DM_UNBALLOON_RESPONSE = 9, |
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DM_MEM_HOT_ADD_REQUEST = 10, |
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DM_MEM_HOT_ADD_RESPONSE = 11, |
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DM_VERSION_03_MAX = 11, |
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/* |
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* Version 1.0. |
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*/ |
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DM_INFO_MESSAGE = 12, |
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DM_VERSION_1_MAX = 12 |
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}; |
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/* |
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* Structures defining the dynamic memory management |
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* protocol. |
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*/ |
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union dm_version { |
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struct { |
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__u16 minor_version; |
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__u16 major_version; |
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}; |
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__u32 version; |
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} __packed; |
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union dm_caps { |
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struct { |
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__u64 balloon:1; |
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__u64 hot_add:1; |
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/* |
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* To support guests that may have alignment |
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* limitations on hot-add, the guest can specify |
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* its alignment requirements; a value of n |
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* represents an alignment of 2^n in mega bytes. |
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*/ |
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__u64 hot_add_alignment:4; |
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__u64 reservedz:58; |
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} cap_bits; |
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__u64 caps; |
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} __packed; |
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union dm_mem_page_range { |
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struct { |
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/* |
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* The PFN number of the first page in the range. |
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* 40 bits is the architectural limit of a PFN |
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* number for AMD64. |
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*/ |
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__u64 start_page:40; |
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/* |
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* The number of pages in the range. |
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*/ |
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__u64 page_cnt:24; |
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} finfo; |
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__u64 page_range; |
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} __packed; |
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/* |
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* The header for all dynamic memory messages: |
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* |
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* type: Type of the message. |
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* size: Size of the message in bytes; including the header. |
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* trans_id: The guest is responsible for manufacturing this ID. |
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*/ |
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struct dm_header { |
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__u16 type; |
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__u16 size; |
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__u32 trans_id; |
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} __packed; |
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/* |
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* A generic message format for dynamic memory. |
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* Specific message formats are defined later in the file. |
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*/ |
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struct dm_message { |
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struct dm_header hdr; |
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__u8 data[]; /* enclosed message */ |
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} __packed; |
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/* |
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* Specific message types supporting the dynamic memory protocol. |
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*/ |
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/* |
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* Version negotiation message. Sent from the guest to the host. |
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* The guest is free to try different versions until the host |
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* accepts the version. |
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* |
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* dm_version: The protocol version requested. |
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* is_last_attempt: If TRUE, this is the last version guest will request. |
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* reservedz: Reserved field, set to zero. |
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*/ |
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struct dm_version_request { |
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struct dm_header hdr; |
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union dm_version version; |
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__u32 is_last_attempt:1; |
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__u32 reservedz:31; |
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} __packed; |
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/* |
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* Version response message; Host to Guest and indicates |
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* if the host has accepted the version sent by the guest. |
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* |
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* is_accepted: If TRUE, host has accepted the version and the guest |
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* should proceed to the next stage of the protocol. FALSE indicates that |
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* guest should re-try with a different version. |
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* |
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* reservedz: Reserved field, set to zero. |
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*/ |
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struct dm_version_response { |
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struct dm_header hdr; |
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__u64 is_accepted:1; |
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__u64 reservedz:63; |
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} __packed; |
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/* |
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* Message reporting capabilities. This is sent from the guest to the |
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* host. |
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*/ |
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struct dm_capabilities { |
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struct dm_header hdr; |
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union dm_caps caps; |
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__u64 min_page_cnt; |
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__u64 max_page_number; |
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} __packed; |
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/* |
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* Response to the capabilities message. This is sent from the host to the |
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* guest. This message notifies if the host has accepted the guest's |
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* capabilities. If the host has not accepted, the guest must shutdown |
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* the service. |
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* |
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* is_accepted: Indicates if the host has accepted guest's capabilities. |
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* reservedz: Must be 0. |
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*/ |
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struct dm_capabilities_resp_msg { |
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struct dm_header hdr; |
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__u64 is_accepted:1; |
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__u64 reservedz:63; |
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} __packed; |
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/* |
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* This message is used to report memory pressure from the guest. |
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* This message is not part of any transaction and there is no |
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* response to this message. |
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* |
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* num_avail: Available memory in pages. |
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* num_committed: Committed memory in pages. |
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* page_file_size: The accumulated size of all page files |
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* in the system in pages. |
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* zero_free: The nunber of zero and free pages. |
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* page_file_writes: The writes to the page file in pages. |
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* io_diff: An indicator of file cache efficiency or page file activity, |
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* calculated as File Cache Page Fault Count - Page Read Count. |
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* This value is in pages. |
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* |
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* Some of these metrics are Windows specific and fortunately |
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* the algorithm on the host side that computes the guest memory |
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* pressure only uses num_committed value. |
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*/ |
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struct dm_status { |
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struct dm_header hdr; |
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__u64 num_avail; |
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__u64 num_committed; |
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__u64 page_file_size; |
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__u64 zero_free; |
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__u32 page_file_writes; |
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__u32 io_diff; |
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} __packed; |
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/* |
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* Message to ask the guest to allocate memory - balloon up message. |
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* This message is sent from the host to the guest. The guest may not be |
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* able to allocate as much memory as requested. |
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* |
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* num_pages: number of pages to allocate. |
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*/ |
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struct dm_balloon { |
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struct dm_header hdr; |
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__u32 num_pages; |
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__u32 reservedz; |
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} __packed; |
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/* |
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* Balloon response message; this message is sent from the guest |
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* to the host in response to the balloon message. |
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* |
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* reservedz: Reserved; must be set to zero. |
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* more_pages: If FALSE, this is the last message of the transaction. |
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* if TRUE there will atleast one more message from the guest. |
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* |
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* range_count: The number of ranges in the range array. |
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* |
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* range_array: An array of page ranges returned to the host. |
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* |
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*/ |
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struct dm_balloon_response { |
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struct dm_header hdr; |
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__u32 reservedz; |
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__u32 more_pages:1; |
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__u32 range_count:31; |
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union dm_mem_page_range range_array[]; |
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} __packed; |
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/* |
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* Un-balloon message; this message is sent from the host |
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* to the guest to give guest more memory. |
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* |
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* more_pages: If FALSE, this is the last message of the transaction. |
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* if TRUE there will atleast one more message from the guest. |
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* |
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* reservedz: Reserved; must be set to zero. |
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* |
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* range_count: The number of ranges in the range array. |
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* |
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* range_array: An array of page ranges returned to the host. |
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* |
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*/ |
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struct dm_unballoon_request { |
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struct dm_header hdr; |
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__u32 more_pages:1; |
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__u32 reservedz:31; |
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__u32 range_count; |
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union dm_mem_page_range range_array[]; |
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} __packed; |
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/* |
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* Un-balloon response message; this message is sent from the guest |
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* to the host in response to an unballoon request. |
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* |
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*/ |
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struct dm_unballoon_response { |
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struct dm_header hdr; |
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} __packed; |
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/* |
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* Hot add request message. Message sent from the host to the guest. |
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* |
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* mem_range: Memory range to hot add. |
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* |
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*/ |
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struct dm_hot_add { |
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struct dm_header hdr; |
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union dm_mem_page_range range; |
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} __packed; |
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/* |
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* Hot add response message. |
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* This message is sent by the guest to report the status of a hot add request. |
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* If page_count is less than the requested page count, then the host should |
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* assume all further hot add requests will fail, since this indicates that |
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* the guest has hit an upper physical memory barrier. |
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* |
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* Hot adds may also fail due to low resources; in this case, the guest must |
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* not complete this message until the hot add can succeed, and the host must |
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* not send a new hot add request until the response is sent. |
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* If VSC fails to hot add memory DYNMEM_NUMBER_OF_UNSUCCESSFUL_HOTADD_ATTEMPTS |
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* times it fails the request. |
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* |
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* |
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* page_count: number of pages that were successfully hot added. |
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* |
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* result: result of the operation 1: success, 0: failure. |
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* |
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*/ |
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struct dm_hot_add_response { |
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struct dm_header hdr; |
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__u32 page_count; |
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__u32 result; |
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} __packed; |
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/* |
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* Types of information sent from host to the guest. |
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*/ |
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enum dm_info_type { |
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INFO_TYPE_MAX_PAGE_CNT = 0, |
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MAX_INFO_TYPE |
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}; |
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/* |
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* Header for the information message. |
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*/ |
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struct dm_info_header { |
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enum dm_info_type type; |
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__u32 data_size; |
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} __packed; |
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/* |
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* This message is sent from the host to the guest to pass |
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* some relevant information (win8 addition). |
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* |
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* reserved: no used. |
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* info_size: size of the information blob. |
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* info: information blob. |
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*/ |
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struct dm_info_msg { |
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struct dm_header hdr; |
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__u32 reserved; |
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__u32 info_size; |
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__u8 info[]; |
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}; |
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/* |
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* End protocol definitions. |
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*/ |
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/* |
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* State to manage hot adding memory into the guest. |
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* The range start_pfn : end_pfn specifies the range |
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* that the host has asked us to hot add. The range |
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* start_pfn : ha_end_pfn specifies the range that we have |
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* currently hot added. We hot add in multiples of 128M |
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* chunks; it is possible that we may not be able to bring |
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* online all the pages in the region. The range |
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* covered_start_pfn:covered_end_pfn defines the pages that can |
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* be brough online. |
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*/ |
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struct hv_hotadd_state { |
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struct list_head list; |
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unsigned long start_pfn; |
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unsigned long covered_start_pfn; |
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unsigned long covered_end_pfn; |
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unsigned long ha_end_pfn; |
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unsigned long end_pfn; |
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/* |
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* A list of gaps. |
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*/ |
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struct list_head gap_list; |
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}; |
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struct hv_hotadd_gap { |
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struct list_head list; |
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unsigned long start_pfn; |
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unsigned long end_pfn; |
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}; |
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struct balloon_state { |
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__u32 num_pages; |
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struct work_struct wrk; |
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}; |
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struct hot_add_wrk { |
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union dm_mem_page_range ha_page_range; |
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union dm_mem_page_range ha_region_range; |
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struct work_struct wrk; |
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}; |
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static bool allow_hibernation; |
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static bool hot_add = true; |
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static bool do_hot_add; |
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/* |
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* Delay reporting memory pressure by |
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* the specified number of seconds. |
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*/ |
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static uint pressure_report_delay = 45; |
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/* |
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* The last time we posted a pressure report to host. |
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*/ |
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static unsigned long last_post_time; |
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module_param(hot_add, bool, (S_IRUGO | S_IWUSR)); |
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MODULE_PARM_DESC(hot_add, "If set attempt memory hot_add"); |
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module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR)); |
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MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure"); |
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static atomic_t trans_id = ATOMIC_INIT(0); |
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static int dm_ring_size = 20 * 1024; |
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/* |
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* Driver specific state. |
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*/ |
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enum hv_dm_state { |
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DM_INITIALIZING = 0, |
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DM_INITIALIZED, |
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DM_BALLOON_UP, |
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DM_BALLOON_DOWN, |
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DM_HOT_ADD, |
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DM_INIT_ERROR |
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}; |
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static __u8 recv_buffer[HV_HYP_PAGE_SIZE]; |
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static __u8 balloon_up_send_buffer[HV_HYP_PAGE_SIZE]; |
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#define PAGES_IN_2M (2 * 1024 * 1024 / PAGE_SIZE) |
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#define HA_CHUNK (128 * 1024 * 1024 / PAGE_SIZE) |
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struct hv_dynmem_device { |
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struct hv_device *dev; |
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enum hv_dm_state state; |
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struct completion host_event; |
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struct completion config_event; |
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/* |
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* Number of pages we have currently ballooned out. |
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*/ |
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unsigned int num_pages_ballooned; |
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unsigned int num_pages_onlined; |
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unsigned int num_pages_added; |
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/* |
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* State to manage the ballooning (up) operation. |
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*/ |
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struct balloon_state balloon_wrk; |
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/* |
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* State to execute the "hot-add" operation. |
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*/ |
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struct hot_add_wrk ha_wrk; |
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/* |
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* This state tracks if the host has specified a hot-add |
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* region. |
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*/ |
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bool host_specified_ha_region; |
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/* |
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* State to synchronize hot-add. |
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*/ |
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struct completion ol_waitevent; |
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/* |
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* This thread handles hot-add |
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* requests from the host as well as notifying |
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* the host with regards to memory pressure in |
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* the guest. |
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*/ |
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struct task_struct *thread; |
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/* |
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* Protects ha_region_list, num_pages_onlined counter and individual |
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* regions from ha_region_list. |
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*/ |
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spinlock_t ha_lock; |
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/* |
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* A list of hot-add regions. |
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*/ |
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struct list_head ha_region_list; |
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/* |
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* We start with the highest version we can support |
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* and downgrade based on the host; we save here the |
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* next version to try. |
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*/ |
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__u32 next_version; |
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/* |
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* The negotiated version agreed by host. |
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*/ |
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__u32 version; |
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struct page_reporting_dev_info pr_dev_info; |
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}; |
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static struct hv_dynmem_device dm_device; |
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static void post_status(struct hv_dynmem_device *dm); |
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#ifdef CONFIG_MEMORY_HOTPLUG |
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static inline bool has_pfn_is_backed(struct hv_hotadd_state *has, |
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unsigned long pfn) |
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{ |
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struct hv_hotadd_gap *gap; |
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/* The page is not backed. */ |
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if ((pfn < has->covered_start_pfn) || (pfn >= has->covered_end_pfn)) |
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return false; |
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/* Check for gaps. */ |
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list_for_each_entry(gap, &has->gap_list, list) { |
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if ((pfn >= gap->start_pfn) && (pfn < gap->end_pfn)) |
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return false; |
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} |
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return true; |
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} |
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static unsigned long hv_page_offline_check(unsigned long start_pfn, |
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unsigned long nr_pages) |
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{ |
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unsigned long pfn = start_pfn, count = 0; |
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struct hv_hotadd_state *has; |
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bool found; |
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while (pfn < start_pfn + nr_pages) { |
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/* |
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* Search for HAS which covers the pfn and when we find one |
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* count how many consequitive PFNs are covered. |
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*/ |
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found = false; |
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list_for_each_entry(has, &dm_device.ha_region_list, list) { |
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while ((pfn >= has->start_pfn) && |
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(pfn < has->end_pfn) && |
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(pfn < start_pfn + nr_pages)) { |
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found = true; |
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if (has_pfn_is_backed(has, pfn)) |
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count++; |
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pfn++; |
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} |
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} |
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/* |
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* This PFN is not in any HAS (e.g. we're offlining a region |
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* which was present at boot), no need to account for it. Go |
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* to the next one. |
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*/ |
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if (!found) |
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pfn++; |
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} |
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return count; |
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} |
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static int hv_memory_notifier(struct notifier_block *nb, unsigned long val, |
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void *v) |
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{ |
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struct memory_notify *mem = (struct memory_notify *)v; |
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unsigned long flags, pfn_count; |
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switch (val) { |
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case MEM_ONLINE: |
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case MEM_CANCEL_ONLINE: |
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complete(&dm_device.ol_waitevent); |
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break; |
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case MEM_OFFLINE: |
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spin_lock_irqsave(&dm_device.ha_lock, flags); |
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pfn_count = hv_page_offline_check(mem->start_pfn, |
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mem->nr_pages); |
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if (pfn_count <= dm_device.num_pages_onlined) { |
|
dm_device.num_pages_onlined -= pfn_count; |
|
} else { |
|
/* |
|
* We're offlining more pages than we managed to online. |
|
* This is unexpected. In any case don't let |
|
* num_pages_onlined wrap around zero. |
|
*/ |
|
WARN_ON_ONCE(1); |
|
dm_device.num_pages_onlined = 0; |
|
} |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
break; |
|
case MEM_GOING_ONLINE: |
|
case MEM_GOING_OFFLINE: |
|
case MEM_CANCEL_OFFLINE: |
|
break; |
|
} |
|
return NOTIFY_OK; |
|
} |
|
|
|
static struct notifier_block hv_memory_nb = { |
|
.notifier_call = hv_memory_notifier, |
|
.priority = 0 |
|
}; |
|
|
|
/* Check if the particular page is backed and can be onlined and online it. */ |
|
static void hv_page_online_one(struct hv_hotadd_state *has, struct page *pg) |
|
{ |
|
if (!has_pfn_is_backed(has, page_to_pfn(pg))) { |
|
if (!PageOffline(pg)) |
|
__SetPageOffline(pg); |
|
return; |
|
} |
|
if (PageOffline(pg)) |
|
__ClearPageOffline(pg); |
|
|
|
/* This frame is currently backed; online the page. */ |
|
generic_online_page(pg, 0); |
|
|
|
lockdep_assert_held(&dm_device.ha_lock); |
|
dm_device.num_pages_onlined++; |
|
} |
|
|
|
static void hv_bring_pgs_online(struct hv_hotadd_state *has, |
|
unsigned long start_pfn, unsigned long size) |
|
{ |
|
int i; |
|
|
|
pr_debug("Online %lu pages starting at pfn 0x%lx\n", size, start_pfn); |
|
for (i = 0; i < size; i++) |
|
hv_page_online_one(has, pfn_to_page(start_pfn + i)); |
|
} |
|
|
|
static void hv_mem_hot_add(unsigned long start, unsigned long size, |
|
unsigned long pfn_count, |
|
struct hv_hotadd_state *has) |
|
{ |
|
int ret = 0; |
|
int i, nid; |
|
unsigned long start_pfn; |
|
unsigned long processed_pfn; |
|
unsigned long total_pfn = pfn_count; |
|
unsigned long flags; |
|
|
|
for (i = 0; i < (size/HA_CHUNK); i++) { |
|
start_pfn = start + (i * HA_CHUNK); |
|
|
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
has->ha_end_pfn += HA_CHUNK; |
|
|
|
if (total_pfn > HA_CHUNK) { |
|
processed_pfn = HA_CHUNK; |
|
total_pfn -= HA_CHUNK; |
|
} else { |
|
processed_pfn = total_pfn; |
|
total_pfn = 0; |
|
} |
|
|
|
has->covered_end_pfn += processed_pfn; |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
|
|
reinit_completion(&dm_device.ol_waitevent); |
|
|
|
nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn)); |
|
ret = add_memory(nid, PFN_PHYS((start_pfn)), |
|
(HA_CHUNK << PAGE_SHIFT), MHP_MERGE_RESOURCE); |
|
|
|
if (ret) { |
|
pr_err("hot_add memory failed error is %d\n", ret); |
|
if (ret == -EEXIST) { |
|
/* |
|
* This error indicates that the error |
|
* is not a transient failure. This is the |
|
* case where the guest's physical address map |
|
* precludes hot adding memory. Stop all further |
|
* memory hot-add. |
|
*/ |
|
do_hot_add = false; |
|
} |
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
has->ha_end_pfn -= HA_CHUNK; |
|
has->covered_end_pfn -= processed_pfn; |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
break; |
|
} |
|
|
|
/* |
|
* Wait for memory to get onlined. If the kernel onlined the |
|
* memory when adding it, this will return directly. Otherwise, |
|
* it will wait for user space to online the memory. This helps |
|
* to avoid adding memory faster than it is getting onlined. As |
|
* adding succeeded, it is ok to proceed even if the memory was |
|
* not onlined in time. |
|
*/ |
|
wait_for_completion_timeout(&dm_device.ol_waitevent, 5 * HZ); |
|
post_status(&dm_device); |
|
} |
|
} |
|
|
|
static void hv_online_page(struct page *pg, unsigned int order) |
|
{ |
|
struct hv_hotadd_state *has; |
|
unsigned long flags; |
|
unsigned long pfn = page_to_pfn(pg); |
|
|
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
list_for_each_entry(has, &dm_device.ha_region_list, list) { |
|
/* The page belongs to a different HAS. */ |
|
if ((pfn < has->start_pfn) || |
|
(pfn + (1UL << order) > has->end_pfn)) |
|
continue; |
|
|
|
hv_bring_pgs_online(has, pfn, 1UL << order); |
|
break; |
|
} |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
} |
|
|
|
static int pfn_covered(unsigned long start_pfn, unsigned long pfn_cnt) |
|
{ |
|
struct hv_hotadd_state *has; |
|
struct hv_hotadd_gap *gap; |
|
unsigned long residual, new_inc; |
|
int ret = 0; |
|
unsigned long flags; |
|
|
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
list_for_each_entry(has, &dm_device.ha_region_list, list) { |
|
/* |
|
* If the pfn range we are dealing with is not in the current |
|
* "hot add block", move on. |
|
*/ |
|
if (start_pfn < has->start_pfn || start_pfn >= has->end_pfn) |
|
continue; |
|
|
|
/* |
|
* If the current start pfn is not where the covered_end |
|
* is, create a gap and update covered_end_pfn. |
|
*/ |
|
if (has->covered_end_pfn != start_pfn) { |
|
gap = kzalloc(sizeof(struct hv_hotadd_gap), GFP_ATOMIC); |
|
if (!gap) { |
|
ret = -ENOMEM; |
|
break; |
|
} |
|
|
|
INIT_LIST_HEAD(&gap->list); |
|
gap->start_pfn = has->covered_end_pfn; |
|
gap->end_pfn = start_pfn; |
|
list_add_tail(&gap->list, &has->gap_list); |
|
|
|
has->covered_end_pfn = start_pfn; |
|
} |
|
|
|
/* |
|
* If the current hot add-request extends beyond |
|
* our current limit; extend it. |
|
*/ |
|
if ((start_pfn + pfn_cnt) > has->end_pfn) { |
|
residual = (start_pfn + pfn_cnt - has->end_pfn); |
|
/* |
|
* Extend the region by multiples of HA_CHUNK. |
|
*/ |
|
new_inc = (residual / HA_CHUNK) * HA_CHUNK; |
|
if (residual % HA_CHUNK) |
|
new_inc += HA_CHUNK; |
|
|
|
has->end_pfn += new_inc; |
|
} |
|
|
|
ret = 1; |
|
break; |
|
} |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
|
|
return ret; |
|
} |
|
|
|
static unsigned long handle_pg_range(unsigned long pg_start, |
|
unsigned long pg_count) |
|
{ |
|
unsigned long start_pfn = pg_start; |
|
unsigned long pfn_cnt = pg_count; |
|
unsigned long size; |
|
struct hv_hotadd_state *has; |
|
unsigned long pgs_ol = 0; |
|
unsigned long old_covered_state; |
|
unsigned long res = 0, flags; |
|
|
|
pr_debug("Hot adding %lu pages starting at pfn 0x%lx.\n", pg_count, |
|
pg_start); |
|
|
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
list_for_each_entry(has, &dm_device.ha_region_list, list) { |
|
/* |
|
* If the pfn range we are dealing with is not in the current |
|
* "hot add block", move on. |
|
*/ |
|
if (start_pfn < has->start_pfn || start_pfn >= has->end_pfn) |
|
continue; |
|
|
|
old_covered_state = has->covered_end_pfn; |
|
|
|
if (start_pfn < has->ha_end_pfn) { |
|
/* |
|
* This is the case where we are backing pages |
|
* in an already hot added region. Bring |
|
* these pages online first. |
|
*/ |
|
pgs_ol = has->ha_end_pfn - start_pfn; |
|
if (pgs_ol > pfn_cnt) |
|
pgs_ol = pfn_cnt; |
|
|
|
has->covered_end_pfn += pgs_ol; |
|
pfn_cnt -= pgs_ol; |
|
/* |
|
* Check if the corresponding memory block is already |
|
* online. It is possible to observe struct pages still |
|
* being uninitialized here so check section instead. |
|
* In case the section is online we need to bring the |
|
* rest of pfns (which were not backed previously) |
|
* online too. |
|
*/ |
|
if (start_pfn > has->start_pfn && |
|
online_section_nr(pfn_to_section_nr(start_pfn))) |
|
hv_bring_pgs_online(has, start_pfn, pgs_ol); |
|
|
|
} |
|
|
|
if ((has->ha_end_pfn < has->end_pfn) && (pfn_cnt > 0)) { |
|
/* |
|
* We have some residual hot add range |
|
* that needs to be hot added; hot add |
|
* it now. Hot add a multiple of |
|
* of HA_CHUNK that fully covers the pages |
|
* we have. |
|
*/ |
|
size = (has->end_pfn - has->ha_end_pfn); |
|
if (pfn_cnt <= size) { |
|
size = ((pfn_cnt / HA_CHUNK) * HA_CHUNK); |
|
if (pfn_cnt % HA_CHUNK) |
|
size += HA_CHUNK; |
|
} else { |
|
pfn_cnt = size; |
|
} |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
hv_mem_hot_add(has->ha_end_pfn, size, pfn_cnt, has); |
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
} |
|
/* |
|
* If we managed to online any pages that were given to us, |
|
* we declare success. |
|
*/ |
|
res = has->covered_end_pfn - old_covered_state; |
|
break; |
|
} |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
|
|
return res; |
|
} |
|
|
|
static unsigned long process_hot_add(unsigned long pg_start, |
|
unsigned long pfn_cnt, |
|
unsigned long rg_start, |
|
unsigned long rg_size) |
|
{ |
|
struct hv_hotadd_state *ha_region = NULL; |
|
int covered; |
|
unsigned long flags; |
|
|
|
if (pfn_cnt == 0) |
|
return 0; |
|
|
|
if (!dm_device.host_specified_ha_region) { |
|
covered = pfn_covered(pg_start, pfn_cnt); |
|
if (covered < 0) |
|
return 0; |
|
|
|
if (covered) |
|
goto do_pg_range; |
|
} |
|
|
|
/* |
|
* If the host has specified a hot-add range; deal with it first. |
|
*/ |
|
|
|
if (rg_size != 0) { |
|
ha_region = kzalloc(sizeof(struct hv_hotadd_state), GFP_KERNEL); |
|
if (!ha_region) |
|
return 0; |
|
|
|
INIT_LIST_HEAD(&ha_region->list); |
|
INIT_LIST_HEAD(&ha_region->gap_list); |
|
|
|
ha_region->start_pfn = rg_start; |
|
ha_region->ha_end_pfn = rg_start; |
|
ha_region->covered_start_pfn = pg_start; |
|
ha_region->covered_end_pfn = pg_start; |
|
ha_region->end_pfn = rg_start + rg_size; |
|
|
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
list_add_tail(&ha_region->list, &dm_device.ha_region_list); |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
} |
|
|
|
do_pg_range: |
|
/* |
|
* Process the page range specified; bringing them |
|
* online if possible. |
|
*/ |
|
return handle_pg_range(pg_start, pfn_cnt); |
|
} |
|
|
|
#endif |
|
|
|
static void hot_add_req(struct work_struct *dummy) |
|
{ |
|
struct dm_hot_add_response resp; |
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
unsigned long pg_start, pfn_cnt; |
|
unsigned long rg_start, rg_sz; |
|
#endif |
|
struct hv_dynmem_device *dm = &dm_device; |
|
|
|
memset(&resp, 0, sizeof(struct dm_hot_add_response)); |
|
resp.hdr.type = DM_MEM_HOT_ADD_RESPONSE; |
|
resp.hdr.size = sizeof(struct dm_hot_add_response); |
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
pg_start = dm->ha_wrk.ha_page_range.finfo.start_page; |
|
pfn_cnt = dm->ha_wrk.ha_page_range.finfo.page_cnt; |
|
|
|
rg_start = dm->ha_wrk.ha_region_range.finfo.start_page; |
|
rg_sz = dm->ha_wrk.ha_region_range.finfo.page_cnt; |
|
|
|
if ((rg_start == 0) && (!dm->host_specified_ha_region)) { |
|
unsigned long region_size; |
|
unsigned long region_start; |
|
|
|
/* |
|
* The host has not specified the hot-add region. |
|
* Based on the hot-add page range being specified, |
|
* compute a hot-add region that can cover the pages |
|
* that need to be hot-added while ensuring the alignment |
|
* and size requirements of Linux as it relates to hot-add. |
|
*/ |
|
region_size = (pfn_cnt / HA_CHUNK) * HA_CHUNK; |
|
if (pfn_cnt % HA_CHUNK) |
|
region_size += HA_CHUNK; |
|
|
|
region_start = (pg_start / HA_CHUNK) * HA_CHUNK; |
|
|
|
rg_start = region_start; |
|
rg_sz = region_size; |
|
} |
|
|
|
if (do_hot_add) |
|
resp.page_count = process_hot_add(pg_start, pfn_cnt, |
|
rg_start, rg_sz); |
|
|
|
dm->num_pages_added += resp.page_count; |
|
#endif |
|
/* |
|
* The result field of the response structure has the |
|
* following semantics: |
|
* |
|
* 1. If all or some pages hot-added: Guest should return success. |
|
* |
|
* 2. If no pages could be hot-added: |
|
* |
|
* If the guest returns success, then the host |
|
* will not attempt any further hot-add operations. This |
|
* signifies a permanent failure. |
|
* |
|
* If the guest returns failure, then this failure will be |
|
* treated as a transient failure and the host may retry the |
|
* hot-add operation after some delay. |
|
*/ |
|
if (resp.page_count > 0) |
|
resp.result = 1; |
|
else if (!do_hot_add) |
|
resp.result = 1; |
|
else |
|
resp.result = 0; |
|
|
|
if (!do_hot_add || resp.page_count == 0) { |
|
if (!allow_hibernation) |
|
pr_err("Memory hot add failed\n"); |
|
else |
|
pr_info("Ignore hot-add request!\n"); |
|
} |
|
|
|
dm->state = DM_INITIALIZED; |
|
resp.hdr.trans_id = atomic_inc_return(&trans_id); |
|
vmbus_sendpacket(dm->dev->channel, &resp, |
|
sizeof(struct dm_hot_add_response), |
|
(unsigned long)NULL, |
|
VM_PKT_DATA_INBAND, 0); |
|
} |
|
|
|
static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg) |
|
{ |
|
struct dm_info_header *info_hdr; |
|
|
|
info_hdr = (struct dm_info_header *)msg->info; |
|
|
|
switch (info_hdr->type) { |
|
case INFO_TYPE_MAX_PAGE_CNT: |
|
if (info_hdr->data_size == sizeof(__u64)) { |
|
__u64 *max_page_count = (__u64 *)&info_hdr[1]; |
|
|
|
pr_info("Max. dynamic memory size: %llu MB\n", |
|
(*max_page_count) >> (20 - HV_HYP_PAGE_SHIFT)); |
|
} |
|
|
|
break; |
|
default: |
|
pr_warn("Received Unknown type: %d\n", info_hdr->type); |
|
} |
|
} |
|
|
|
static unsigned long compute_balloon_floor(void) |
|
{ |
|
unsigned long min_pages; |
|
unsigned long nr_pages = totalram_pages(); |
|
#define MB2PAGES(mb) ((mb) << (20 - PAGE_SHIFT)) |
|
/* Simple continuous piecewiese linear function: |
|
* max MiB -> min MiB gradient |
|
* 0 0 |
|
* 16 16 |
|
* 32 24 |
|
* 128 72 (1/2) |
|
* 512 168 (1/4) |
|
* 2048 360 (1/8) |
|
* 8192 744 (1/16) |
|
* 32768 1512 (1/32) |
|
*/ |
|
if (nr_pages < MB2PAGES(128)) |
|
min_pages = MB2PAGES(8) + (nr_pages >> 1); |
|
else if (nr_pages < MB2PAGES(512)) |
|
min_pages = MB2PAGES(40) + (nr_pages >> 2); |
|
else if (nr_pages < MB2PAGES(2048)) |
|
min_pages = MB2PAGES(104) + (nr_pages >> 3); |
|
else if (nr_pages < MB2PAGES(8192)) |
|
min_pages = MB2PAGES(232) + (nr_pages >> 4); |
|
else |
|
min_pages = MB2PAGES(488) + (nr_pages >> 5); |
|
#undef MB2PAGES |
|
return min_pages; |
|
} |
|
|
|
/* |
|
* Post our status as it relates memory pressure to the |
|
* host. Host expects the guests to post this status |
|
* periodically at 1 second intervals. |
|
* |
|
* The metrics specified in this protocol are very Windows |
|
* specific and so we cook up numbers here to convey our memory |
|
* pressure. |
|
*/ |
|
|
|
static void post_status(struct hv_dynmem_device *dm) |
|
{ |
|
struct dm_status status; |
|
unsigned long now = jiffies; |
|
unsigned long last_post = last_post_time; |
|
|
|
if (pressure_report_delay > 0) { |
|
--pressure_report_delay; |
|
return; |
|
} |
|
|
|
if (!time_after(now, (last_post_time + HZ))) |
|
return; |
|
|
|
memset(&status, 0, sizeof(struct dm_status)); |
|
status.hdr.type = DM_STATUS_REPORT; |
|
status.hdr.size = sizeof(struct dm_status); |
|
status.hdr.trans_id = atomic_inc_return(&trans_id); |
|
|
|
/* |
|
* The host expects the guest to report free and committed memory. |
|
* Furthermore, the host expects the pressure information to include |
|
* the ballooned out pages. For a given amount of memory that we are |
|
* managing we need to compute a floor below which we should not |
|
* balloon. Compute this and add it to the pressure report. |
|
* We also need to report all offline pages (num_pages_added - |
|
* num_pages_onlined) as committed to the host, otherwise it can try |
|
* asking us to balloon them out. |
|
*/ |
|
status.num_avail = si_mem_available(); |
|
status.num_committed = vm_memory_committed() + |
|
dm->num_pages_ballooned + |
|
(dm->num_pages_added > dm->num_pages_onlined ? |
|
dm->num_pages_added - dm->num_pages_onlined : 0) + |
|
compute_balloon_floor(); |
|
|
|
trace_balloon_status(status.num_avail, status.num_committed, |
|
vm_memory_committed(), dm->num_pages_ballooned, |
|
dm->num_pages_added, dm->num_pages_onlined); |
|
/* |
|
* If our transaction ID is no longer current, just don't |
|
* send the status. This can happen if we were interrupted |
|
* after we picked our transaction ID. |
|
*/ |
|
if (status.hdr.trans_id != atomic_read(&trans_id)) |
|
return; |
|
|
|
/* |
|
* If the last post time that we sampled has changed, |
|
* we have raced, don't post the status. |
|
*/ |
|
if (last_post != last_post_time) |
|
return; |
|
|
|
last_post_time = jiffies; |
|
vmbus_sendpacket(dm->dev->channel, &status, |
|
sizeof(struct dm_status), |
|
(unsigned long)NULL, |
|
VM_PKT_DATA_INBAND, 0); |
|
|
|
} |
|
|
|
static void free_balloon_pages(struct hv_dynmem_device *dm, |
|
union dm_mem_page_range *range_array) |
|
{ |
|
int num_pages = range_array->finfo.page_cnt; |
|
__u64 start_frame = range_array->finfo.start_page; |
|
struct page *pg; |
|
int i; |
|
|
|
for (i = 0; i < num_pages; i++) { |
|
pg = pfn_to_page(i + start_frame); |
|
__ClearPageOffline(pg); |
|
__free_page(pg); |
|
dm->num_pages_ballooned--; |
|
adjust_managed_page_count(pg, 1); |
|
} |
|
} |
|
|
|
|
|
|
|
static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm, |
|
unsigned int num_pages, |
|
struct dm_balloon_response *bl_resp, |
|
int alloc_unit) |
|
{ |
|
unsigned int i, j; |
|
struct page *pg; |
|
|
|
for (i = 0; i < num_pages / alloc_unit; i++) { |
|
if (bl_resp->hdr.size + sizeof(union dm_mem_page_range) > |
|
HV_HYP_PAGE_SIZE) |
|
return i * alloc_unit; |
|
|
|
/* |
|
* We execute this code in a thread context. Furthermore, |
|
* we don't want the kernel to try too hard. |
|
*/ |
|
pg = alloc_pages(GFP_HIGHUSER | __GFP_NORETRY | |
|
__GFP_NOMEMALLOC | __GFP_NOWARN, |
|
get_order(alloc_unit << PAGE_SHIFT)); |
|
|
|
if (!pg) |
|
return i * alloc_unit; |
|
|
|
dm->num_pages_ballooned += alloc_unit; |
|
|
|
/* |
|
* If we allocatted 2M pages; split them so we |
|
* can free them in any order we get. |
|
*/ |
|
|
|
if (alloc_unit != 1) |
|
split_page(pg, get_order(alloc_unit << PAGE_SHIFT)); |
|
|
|
/* mark all pages offline */ |
|
for (j = 0; j < alloc_unit; j++) { |
|
__SetPageOffline(pg + j); |
|
adjust_managed_page_count(pg + j, -1); |
|
} |
|
|
|
bl_resp->range_count++; |
|
bl_resp->range_array[i].finfo.start_page = |
|
page_to_pfn(pg); |
|
bl_resp->range_array[i].finfo.page_cnt = alloc_unit; |
|
bl_resp->hdr.size += sizeof(union dm_mem_page_range); |
|
|
|
} |
|
|
|
return i * alloc_unit; |
|
} |
|
|
|
static void balloon_up(struct work_struct *dummy) |
|
{ |
|
unsigned int num_pages = dm_device.balloon_wrk.num_pages; |
|
unsigned int num_ballooned = 0; |
|
struct dm_balloon_response *bl_resp; |
|
int alloc_unit; |
|
int ret; |
|
bool done = false; |
|
int i; |
|
long avail_pages; |
|
unsigned long floor; |
|
|
|
/* |
|
* We will attempt 2M allocations. However, if we fail to |
|
* allocate 2M chunks, we will go back to PAGE_SIZE allocations. |
|
*/ |
|
alloc_unit = PAGES_IN_2M; |
|
|
|
avail_pages = si_mem_available(); |
|
floor = compute_balloon_floor(); |
|
|
|
/* Refuse to balloon below the floor. */ |
|
if (avail_pages < num_pages || avail_pages - num_pages < floor) { |
|
pr_info("Balloon request will be partially fulfilled. %s\n", |
|
avail_pages < num_pages ? "Not enough memory." : |
|
"Balloon floor reached."); |
|
|
|
num_pages = avail_pages > floor ? (avail_pages - floor) : 0; |
|
} |
|
|
|
while (!done) { |
|
memset(balloon_up_send_buffer, 0, HV_HYP_PAGE_SIZE); |
|
bl_resp = (struct dm_balloon_response *)balloon_up_send_buffer; |
|
bl_resp->hdr.type = DM_BALLOON_RESPONSE; |
|
bl_resp->hdr.size = sizeof(struct dm_balloon_response); |
|
bl_resp->more_pages = 1; |
|
|
|
num_pages -= num_ballooned; |
|
num_ballooned = alloc_balloon_pages(&dm_device, num_pages, |
|
bl_resp, alloc_unit); |
|
|
|
if (alloc_unit != 1 && num_ballooned == 0) { |
|
alloc_unit = 1; |
|
continue; |
|
} |
|
|
|
if (num_ballooned == 0 || num_ballooned == num_pages) { |
|
pr_debug("Ballooned %u out of %u requested pages.\n", |
|
num_pages, dm_device.balloon_wrk.num_pages); |
|
|
|
bl_resp->more_pages = 0; |
|
done = true; |
|
dm_device.state = DM_INITIALIZED; |
|
} |
|
|
|
/* |
|
* We are pushing a lot of data through the channel; |
|
* deal with transient failures caused because of the |
|
* lack of space in the ring buffer. |
|
*/ |
|
|
|
do { |
|
bl_resp->hdr.trans_id = atomic_inc_return(&trans_id); |
|
ret = vmbus_sendpacket(dm_device.dev->channel, |
|
bl_resp, |
|
bl_resp->hdr.size, |
|
(unsigned long)NULL, |
|
VM_PKT_DATA_INBAND, 0); |
|
|
|
if (ret == -EAGAIN) |
|
msleep(20); |
|
post_status(&dm_device); |
|
} while (ret == -EAGAIN); |
|
|
|
if (ret) { |
|
/* |
|
* Free up the memory we allocatted. |
|
*/ |
|
pr_err("Balloon response failed\n"); |
|
|
|
for (i = 0; i < bl_resp->range_count; i++) |
|
free_balloon_pages(&dm_device, |
|
&bl_resp->range_array[i]); |
|
|
|
done = true; |
|
} |
|
} |
|
|
|
} |
|
|
|
static void balloon_down(struct hv_dynmem_device *dm, |
|
struct dm_unballoon_request *req) |
|
{ |
|
union dm_mem_page_range *range_array = req->range_array; |
|
int range_count = req->range_count; |
|
struct dm_unballoon_response resp; |
|
int i; |
|
unsigned int prev_pages_ballooned = dm->num_pages_ballooned; |
|
|
|
for (i = 0; i < range_count; i++) { |
|
free_balloon_pages(dm, &range_array[i]); |
|
complete(&dm_device.config_event); |
|
} |
|
|
|
pr_debug("Freed %u ballooned pages.\n", |
|
prev_pages_ballooned - dm->num_pages_ballooned); |
|
|
|
if (req->more_pages == 1) |
|
return; |
|
|
|
memset(&resp, 0, sizeof(struct dm_unballoon_response)); |
|
resp.hdr.type = DM_UNBALLOON_RESPONSE; |
|
resp.hdr.trans_id = atomic_inc_return(&trans_id); |
|
resp.hdr.size = sizeof(struct dm_unballoon_response); |
|
|
|
vmbus_sendpacket(dm_device.dev->channel, &resp, |
|
sizeof(struct dm_unballoon_response), |
|
(unsigned long)NULL, |
|
VM_PKT_DATA_INBAND, 0); |
|
|
|
dm->state = DM_INITIALIZED; |
|
} |
|
|
|
static void balloon_onchannelcallback(void *context); |
|
|
|
static int dm_thread_func(void *dm_dev) |
|
{ |
|
struct hv_dynmem_device *dm = dm_dev; |
|
|
|
while (!kthread_should_stop()) { |
|
wait_for_completion_interruptible_timeout( |
|
&dm_device.config_event, 1*HZ); |
|
/* |
|
* The host expects us to post information on the memory |
|
* pressure every second. |
|
*/ |
|
reinit_completion(&dm_device.config_event); |
|
post_status(dm); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
|
|
static void version_resp(struct hv_dynmem_device *dm, |
|
struct dm_version_response *vresp) |
|
{ |
|
struct dm_version_request version_req; |
|
int ret; |
|
|
|
if (vresp->is_accepted) { |
|
/* |
|
* We are done; wakeup the |
|
* context waiting for version |
|
* negotiation. |
|
*/ |
|
complete(&dm->host_event); |
|
return; |
|
} |
|
/* |
|
* If there are more versions to try, continue |
|
* with negotiations; if not |
|
* shutdown the service since we are not able |
|
* to negotiate a suitable version number |
|
* with the host. |
|
*/ |
|
if (dm->next_version == 0) |
|
goto version_error; |
|
|
|
memset(&version_req, 0, sizeof(struct dm_version_request)); |
|
version_req.hdr.type = DM_VERSION_REQUEST; |
|
version_req.hdr.size = sizeof(struct dm_version_request); |
|
version_req.hdr.trans_id = atomic_inc_return(&trans_id); |
|
version_req.version.version = dm->next_version; |
|
dm->version = version_req.version.version; |
|
|
|
/* |
|
* Set the next version to try in case current version fails. |
|
* Win7 protocol ought to be the last one to try. |
|
*/ |
|
switch (version_req.version.version) { |
|
case DYNMEM_PROTOCOL_VERSION_WIN8: |
|
dm->next_version = DYNMEM_PROTOCOL_VERSION_WIN7; |
|
version_req.is_last_attempt = 0; |
|
break; |
|
default: |
|
dm->next_version = 0; |
|
version_req.is_last_attempt = 1; |
|
} |
|
|
|
ret = vmbus_sendpacket(dm->dev->channel, &version_req, |
|
sizeof(struct dm_version_request), |
|
(unsigned long)NULL, |
|
VM_PKT_DATA_INBAND, 0); |
|
|
|
if (ret) |
|
goto version_error; |
|
|
|
return; |
|
|
|
version_error: |
|
dm->state = DM_INIT_ERROR; |
|
complete(&dm->host_event); |
|
} |
|
|
|
static void cap_resp(struct hv_dynmem_device *dm, |
|
struct dm_capabilities_resp_msg *cap_resp) |
|
{ |
|
if (!cap_resp->is_accepted) { |
|
pr_err("Capabilities not accepted by host\n"); |
|
dm->state = DM_INIT_ERROR; |
|
} |
|
complete(&dm->host_event); |
|
} |
|
|
|
static void balloon_onchannelcallback(void *context) |
|
{ |
|
struct hv_device *dev = context; |
|
u32 recvlen; |
|
u64 requestid; |
|
struct dm_message *dm_msg; |
|
struct dm_header *dm_hdr; |
|
struct hv_dynmem_device *dm = hv_get_drvdata(dev); |
|
struct dm_balloon *bal_msg; |
|
struct dm_hot_add *ha_msg; |
|
union dm_mem_page_range *ha_pg_range; |
|
union dm_mem_page_range *ha_region; |
|
|
|
memset(recv_buffer, 0, sizeof(recv_buffer)); |
|
vmbus_recvpacket(dev->channel, recv_buffer, |
|
HV_HYP_PAGE_SIZE, &recvlen, &requestid); |
|
|
|
if (recvlen > 0) { |
|
dm_msg = (struct dm_message *)recv_buffer; |
|
dm_hdr = &dm_msg->hdr; |
|
|
|
switch (dm_hdr->type) { |
|
case DM_VERSION_RESPONSE: |
|
version_resp(dm, |
|
(struct dm_version_response *)dm_msg); |
|
break; |
|
|
|
case DM_CAPABILITIES_RESPONSE: |
|
cap_resp(dm, |
|
(struct dm_capabilities_resp_msg *)dm_msg); |
|
break; |
|
|
|
case DM_BALLOON_REQUEST: |
|
if (allow_hibernation) { |
|
pr_info("Ignore balloon-up request!\n"); |
|
break; |
|
} |
|
|
|
if (dm->state == DM_BALLOON_UP) |
|
pr_warn("Currently ballooning\n"); |
|
bal_msg = (struct dm_balloon *)recv_buffer; |
|
dm->state = DM_BALLOON_UP; |
|
dm_device.balloon_wrk.num_pages = bal_msg->num_pages; |
|
schedule_work(&dm_device.balloon_wrk.wrk); |
|
break; |
|
|
|
case DM_UNBALLOON_REQUEST: |
|
if (allow_hibernation) { |
|
pr_info("Ignore balloon-down request!\n"); |
|
break; |
|
} |
|
|
|
dm->state = DM_BALLOON_DOWN; |
|
balloon_down(dm, |
|
(struct dm_unballoon_request *)recv_buffer); |
|
break; |
|
|
|
case DM_MEM_HOT_ADD_REQUEST: |
|
if (dm->state == DM_HOT_ADD) |
|
pr_warn("Currently hot-adding\n"); |
|
dm->state = DM_HOT_ADD; |
|
ha_msg = (struct dm_hot_add *)recv_buffer; |
|
if (ha_msg->hdr.size == sizeof(struct dm_hot_add)) { |
|
/* |
|
* This is a normal hot-add request specifying |
|
* hot-add memory. |
|
*/ |
|
dm->host_specified_ha_region = false; |
|
ha_pg_range = &ha_msg->range; |
|
dm->ha_wrk.ha_page_range = *ha_pg_range; |
|
dm->ha_wrk.ha_region_range.page_range = 0; |
|
} else { |
|
/* |
|
* Host is specifying that we first hot-add |
|
* a region and then partially populate this |
|
* region. |
|
*/ |
|
dm->host_specified_ha_region = true; |
|
ha_pg_range = &ha_msg->range; |
|
ha_region = &ha_pg_range[1]; |
|
dm->ha_wrk.ha_page_range = *ha_pg_range; |
|
dm->ha_wrk.ha_region_range = *ha_region; |
|
} |
|
schedule_work(&dm_device.ha_wrk.wrk); |
|
break; |
|
|
|
case DM_INFO_MESSAGE: |
|
process_info(dm, (struct dm_info_msg *)dm_msg); |
|
break; |
|
|
|
default: |
|
pr_warn("Unhandled message: type: %d\n", dm_hdr->type); |
|
|
|
} |
|
} |
|
|
|
} |
|
|
|
/* Hyper-V only supports reporting 2MB pages or higher */ |
|
#define HV_MIN_PAGE_REPORTING_ORDER 9 |
|
#define HV_MIN_PAGE_REPORTING_LEN (HV_HYP_PAGE_SIZE << HV_MIN_PAGE_REPORTING_ORDER) |
|
static int hv_free_page_report(struct page_reporting_dev_info *pr_dev_info, |
|
struct scatterlist *sgl, unsigned int nents) |
|
{ |
|
unsigned long flags; |
|
struct hv_memory_hint *hint; |
|
int i; |
|
u64 status; |
|
struct scatterlist *sg; |
|
|
|
WARN_ON_ONCE(nents > HV_MEMORY_HINT_MAX_GPA_PAGE_RANGES); |
|
WARN_ON_ONCE(sgl->length < HV_MIN_PAGE_REPORTING_LEN); |
|
local_irq_save(flags); |
|
hint = *(struct hv_memory_hint **)this_cpu_ptr(hyperv_pcpu_input_arg); |
|
if (!hint) { |
|
local_irq_restore(flags); |
|
return -ENOSPC; |
|
} |
|
|
|
hint->type = HV_EXT_MEMORY_HEAT_HINT_TYPE_COLD_DISCARD; |
|
hint->reserved = 0; |
|
for_each_sg(sgl, sg, nents, i) { |
|
union hv_gpa_page_range *range; |
|
|
|
range = &hint->ranges[i]; |
|
range->address_space = 0; |
|
/* page reporting only reports 2MB pages or higher */ |
|
range->page.largepage = 1; |
|
range->page.additional_pages = |
|
(sg->length / HV_MIN_PAGE_REPORTING_LEN) - 1; |
|
range->page_size = HV_GPA_PAGE_RANGE_PAGE_SIZE_2MB; |
|
range->base_large_pfn = |
|
page_to_hvpfn(sg_page(sg)) >> HV_MIN_PAGE_REPORTING_ORDER; |
|
} |
|
|
|
status = hv_do_rep_hypercall(HV_EXT_CALL_MEMORY_HEAT_HINT, nents, 0, |
|
hint, NULL); |
|
local_irq_restore(flags); |
|
if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS) { |
|
pr_err("Cold memory discard hypercall failed with status %llx\n", |
|
status); |
|
return -EINVAL; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static void enable_page_reporting(void) |
|
{ |
|
int ret; |
|
|
|
/* Essentially, validating 'PAGE_REPORTING_MIN_ORDER' is big enough. */ |
|
if (pageblock_order < HV_MIN_PAGE_REPORTING_ORDER) { |
|
pr_debug("Cold memory discard is only supported on 2MB pages and above\n"); |
|
return; |
|
} |
|
|
|
if (!hv_query_ext_cap(HV_EXT_CAPABILITY_MEMORY_COLD_DISCARD_HINT)) { |
|
pr_debug("Cold memory discard hint not supported by Hyper-V\n"); |
|
return; |
|
} |
|
|
|
BUILD_BUG_ON(PAGE_REPORTING_CAPACITY > HV_MEMORY_HINT_MAX_GPA_PAGE_RANGES); |
|
dm_device.pr_dev_info.report = hv_free_page_report; |
|
ret = page_reporting_register(&dm_device.pr_dev_info); |
|
if (ret < 0) { |
|
dm_device.pr_dev_info.report = NULL; |
|
pr_err("Failed to enable cold memory discard: %d\n", ret); |
|
} else { |
|
pr_info("Cold memory discard hint enabled\n"); |
|
} |
|
} |
|
|
|
static void disable_page_reporting(void) |
|
{ |
|
if (dm_device.pr_dev_info.report) { |
|
page_reporting_unregister(&dm_device.pr_dev_info); |
|
dm_device.pr_dev_info.report = NULL; |
|
} |
|
} |
|
|
|
static int balloon_connect_vsp(struct hv_device *dev) |
|
{ |
|
struct dm_version_request version_req; |
|
struct dm_capabilities cap_msg; |
|
unsigned long t; |
|
int ret; |
|
|
|
ret = vmbus_open(dev->channel, dm_ring_size, dm_ring_size, NULL, 0, |
|
balloon_onchannelcallback, dev); |
|
if (ret) |
|
return ret; |
|
|
|
/* |
|
* Initiate the hand shake with the host and negotiate |
|
* a version that the host can support. We start with the |
|
* highest version number and go down if the host cannot |
|
* support it. |
|
*/ |
|
memset(&version_req, 0, sizeof(struct dm_version_request)); |
|
version_req.hdr.type = DM_VERSION_REQUEST; |
|
version_req.hdr.size = sizeof(struct dm_version_request); |
|
version_req.hdr.trans_id = atomic_inc_return(&trans_id); |
|
version_req.version.version = DYNMEM_PROTOCOL_VERSION_WIN10; |
|
version_req.is_last_attempt = 0; |
|
dm_device.version = version_req.version.version; |
|
|
|
ret = vmbus_sendpacket(dev->channel, &version_req, |
|
sizeof(struct dm_version_request), |
|
(unsigned long)NULL, VM_PKT_DATA_INBAND, 0); |
|
if (ret) |
|
goto out; |
|
|
|
t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ); |
|
if (t == 0) { |
|
ret = -ETIMEDOUT; |
|
goto out; |
|
} |
|
|
|
/* |
|
* If we could not negotiate a compatible version with the host |
|
* fail the probe function. |
|
*/ |
|
if (dm_device.state == DM_INIT_ERROR) { |
|
ret = -EPROTO; |
|
goto out; |
|
} |
|
|
|
pr_info("Using Dynamic Memory protocol version %u.%u\n", |
|
DYNMEM_MAJOR_VERSION(dm_device.version), |
|
DYNMEM_MINOR_VERSION(dm_device.version)); |
|
|
|
/* |
|
* Now submit our capabilities to the host. |
|
*/ |
|
memset(&cap_msg, 0, sizeof(struct dm_capabilities)); |
|
cap_msg.hdr.type = DM_CAPABILITIES_REPORT; |
|
cap_msg.hdr.size = sizeof(struct dm_capabilities); |
|
cap_msg.hdr.trans_id = atomic_inc_return(&trans_id); |
|
|
|
/* |
|
* When hibernation (i.e. virtual ACPI S4 state) is enabled, the host |
|
* currently still requires the bits to be set, so we have to add code |
|
* to fail the host's hot-add and balloon up/down requests, if any. |
|
*/ |
|
cap_msg.caps.cap_bits.balloon = 1; |
|
cap_msg.caps.cap_bits.hot_add = 1; |
|
|
|
/* |
|
* Specify our alignment requirements as it relates |
|
* memory hot-add. Specify 128MB alignment. |
|
*/ |
|
cap_msg.caps.cap_bits.hot_add_alignment = 7; |
|
|
|
/* |
|
* Currently the host does not use these |
|
* values and we set them to what is done in the |
|
* Windows driver. |
|
*/ |
|
cap_msg.min_page_cnt = 0; |
|
cap_msg.max_page_number = -1; |
|
|
|
ret = vmbus_sendpacket(dev->channel, &cap_msg, |
|
sizeof(struct dm_capabilities), |
|
(unsigned long)NULL, VM_PKT_DATA_INBAND, 0); |
|
if (ret) |
|
goto out; |
|
|
|
t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ); |
|
if (t == 0) { |
|
ret = -ETIMEDOUT; |
|
goto out; |
|
} |
|
|
|
/* |
|
* If the host does not like our capabilities, |
|
* fail the probe function. |
|
*/ |
|
if (dm_device.state == DM_INIT_ERROR) { |
|
ret = -EPROTO; |
|
goto out; |
|
} |
|
|
|
return 0; |
|
out: |
|
vmbus_close(dev->channel); |
|
return ret; |
|
} |
|
|
|
static int balloon_probe(struct hv_device *dev, |
|
const struct hv_vmbus_device_id *dev_id) |
|
{ |
|
int ret; |
|
|
|
allow_hibernation = hv_is_hibernation_supported(); |
|
if (allow_hibernation) |
|
hot_add = false; |
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
do_hot_add = hot_add; |
|
#else |
|
do_hot_add = false; |
|
#endif |
|
dm_device.dev = dev; |
|
dm_device.state = DM_INITIALIZING; |
|
dm_device.next_version = DYNMEM_PROTOCOL_VERSION_WIN8; |
|
init_completion(&dm_device.host_event); |
|
init_completion(&dm_device.config_event); |
|
INIT_LIST_HEAD(&dm_device.ha_region_list); |
|
spin_lock_init(&dm_device.ha_lock); |
|
INIT_WORK(&dm_device.balloon_wrk.wrk, balloon_up); |
|
INIT_WORK(&dm_device.ha_wrk.wrk, hot_add_req); |
|
dm_device.host_specified_ha_region = false; |
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
set_online_page_callback(&hv_online_page); |
|
init_completion(&dm_device.ol_waitevent); |
|
register_memory_notifier(&hv_memory_nb); |
|
#endif |
|
|
|
hv_set_drvdata(dev, &dm_device); |
|
|
|
ret = balloon_connect_vsp(dev); |
|
if (ret != 0) |
|
return ret; |
|
|
|
enable_page_reporting(); |
|
dm_device.state = DM_INITIALIZED; |
|
|
|
dm_device.thread = |
|
kthread_run(dm_thread_func, &dm_device, "hv_balloon"); |
|
if (IS_ERR(dm_device.thread)) { |
|
ret = PTR_ERR(dm_device.thread); |
|
goto probe_error; |
|
} |
|
|
|
return 0; |
|
|
|
probe_error: |
|
dm_device.state = DM_INIT_ERROR; |
|
dm_device.thread = NULL; |
|
disable_page_reporting(); |
|
vmbus_close(dev->channel); |
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
unregister_memory_notifier(&hv_memory_nb); |
|
restore_online_page_callback(&hv_online_page); |
|
#endif |
|
return ret; |
|
} |
|
|
|
static int balloon_remove(struct hv_device *dev) |
|
{ |
|
struct hv_dynmem_device *dm = hv_get_drvdata(dev); |
|
struct hv_hotadd_state *has, *tmp; |
|
struct hv_hotadd_gap *gap, *tmp_gap; |
|
unsigned long flags; |
|
|
|
if (dm->num_pages_ballooned != 0) |
|
pr_warn("Ballooned pages: %d\n", dm->num_pages_ballooned); |
|
|
|
cancel_work_sync(&dm->balloon_wrk.wrk); |
|
cancel_work_sync(&dm->ha_wrk.wrk); |
|
|
|
kthread_stop(dm->thread); |
|
disable_page_reporting(); |
|
vmbus_close(dev->channel); |
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
unregister_memory_notifier(&hv_memory_nb); |
|
restore_online_page_callback(&hv_online_page); |
|
#endif |
|
spin_lock_irqsave(&dm_device.ha_lock, flags); |
|
list_for_each_entry_safe(has, tmp, &dm->ha_region_list, list) { |
|
list_for_each_entry_safe(gap, tmp_gap, &has->gap_list, list) { |
|
list_del(&gap->list); |
|
kfree(gap); |
|
} |
|
list_del(&has->list); |
|
kfree(has); |
|
} |
|
spin_unlock_irqrestore(&dm_device.ha_lock, flags); |
|
|
|
return 0; |
|
} |
|
|
|
static int balloon_suspend(struct hv_device *hv_dev) |
|
{ |
|
struct hv_dynmem_device *dm = hv_get_drvdata(hv_dev); |
|
|
|
tasklet_disable(&hv_dev->channel->callback_event); |
|
|
|
cancel_work_sync(&dm->balloon_wrk.wrk); |
|
cancel_work_sync(&dm->ha_wrk.wrk); |
|
|
|
if (dm->thread) { |
|
kthread_stop(dm->thread); |
|
dm->thread = NULL; |
|
vmbus_close(hv_dev->channel); |
|
} |
|
|
|
tasklet_enable(&hv_dev->channel->callback_event); |
|
|
|
return 0; |
|
|
|
} |
|
|
|
static int balloon_resume(struct hv_device *dev) |
|
{ |
|
int ret; |
|
|
|
dm_device.state = DM_INITIALIZING; |
|
|
|
ret = balloon_connect_vsp(dev); |
|
|
|
if (ret != 0) |
|
goto out; |
|
|
|
dm_device.thread = |
|
kthread_run(dm_thread_func, &dm_device, "hv_balloon"); |
|
if (IS_ERR(dm_device.thread)) { |
|
ret = PTR_ERR(dm_device.thread); |
|
dm_device.thread = NULL; |
|
goto close_channel; |
|
} |
|
|
|
dm_device.state = DM_INITIALIZED; |
|
return 0; |
|
close_channel: |
|
vmbus_close(dev->channel); |
|
out: |
|
dm_device.state = DM_INIT_ERROR; |
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
unregister_memory_notifier(&hv_memory_nb); |
|
restore_online_page_callback(&hv_online_page); |
|
#endif |
|
return ret; |
|
} |
|
|
|
static const struct hv_vmbus_device_id id_table[] = { |
|
/* Dynamic Memory Class ID */ |
|
/* 525074DC-8985-46e2-8057-A307DC18A502 */ |
|
{ HV_DM_GUID, }, |
|
{ }, |
|
}; |
|
|
|
MODULE_DEVICE_TABLE(vmbus, id_table); |
|
|
|
static struct hv_driver balloon_drv = { |
|
.name = "hv_balloon", |
|
.id_table = id_table, |
|
.probe = balloon_probe, |
|
.remove = balloon_remove, |
|
.suspend = balloon_suspend, |
|
.resume = balloon_resume, |
|
.driver = { |
|
.probe_type = PROBE_PREFER_ASYNCHRONOUS, |
|
}, |
|
}; |
|
|
|
static int __init init_balloon_drv(void) |
|
{ |
|
|
|
return vmbus_driver_register(&balloon_drv); |
|
} |
|
|
|
module_init(init_balloon_drv); |
|
|
|
MODULE_DESCRIPTION("Hyper-V Balloon"); |
|
MODULE_LICENSE("GPL");
|
|
|