![K. Y. Srinivasan](/assets/img/avatar_default.png)
If memory hot-add fails with the error -EEXIST, then this is a permanent failure. Notify the host of this information, so the host will not attempt hot-add again. If the failure were a transient failure, host will attempt a hot-add after some delay. In this version of the patch, I have added some additional comments to clarify how the host treats different failure conditions. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1526 lines
36 KiB
C
1526 lines
36 KiB
C
/*
|
|
* Copyright (c) 2012, Microsoft Corporation.
|
|
*
|
|
* Author:
|
|
* K. Y. Srinivasan <kys@microsoft.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 as published
|
|
* by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
|
|
* NON INFRINGEMENT. See the GNU General Public License for more
|
|
* details.
|
|
*
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/mman.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/completion.h>
|
|
#include <linux/memory_hotplug.h>
|
|
#include <linux/memory.h>
|
|
#include <linux/notifier.h>
|
|
#include <linux/percpu_counter.h>
|
|
|
|
#include <linux/hyperv.h>
|
|
|
|
/*
|
|
* We begin with definitions supporting the Dynamic Memory protocol
|
|
* with the host.
|
|
*
|
|
* Begin protocol definitions.
|
|
*/
|
|
|
|
|
|
|
|
/*
|
|
* Protocol versions. The low word is the minor version, the high word the major
|
|
* version.
|
|
*
|
|
* History:
|
|
* Initial version 1.0
|
|
* Changed to 0.1 on 2009/03/25
|
|
* Changes to 0.2 on 2009/05/14
|
|
* Changes to 0.3 on 2009/12/03
|
|
* Changed to 1.0 on 2011/04/05
|
|
*/
|
|
|
|
#define DYNMEM_MAKE_VERSION(Major, Minor) ((__u32)(((Major) << 16) | (Minor)))
|
|
#define DYNMEM_MAJOR_VERSION(Version) ((__u32)(Version) >> 16)
|
|
#define DYNMEM_MINOR_VERSION(Version) ((__u32)(Version) & 0xff)
|
|
|
|
enum {
|
|
DYNMEM_PROTOCOL_VERSION_1 = DYNMEM_MAKE_VERSION(0, 3),
|
|
DYNMEM_PROTOCOL_VERSION_2 = DYNMEM_MAKE_VERSION(1, 0),
|
|
|
|
DYNMEM_PROTOCOL_VERSION_WIN7 = DYNMEM_PROTOCOL_VERSION_1,
|
|
DYNMEM_PROTOCOL_VERSION_WIN8 = DYNMEM_PROTOCOL_VERSION_2,
|
|
|
|
DYNMEM_PROTOCOL_VERSION_CURRENT = DYNMEM_PROTOCOL_VERSION_WIN8
|
|
};
|
|
|
|
|
|
|
|
/*
|
|
* Message Types
|
|
*/
|
|
|
|
enum dm_message_type {
|
|
/*
|
|
* Version 0.3
|
|
*/
|
|
DM_ERROR = 0,
|
|
DM_VERSION_REQUEST = 1,
|
|
DM_VERSION_RESPONSE = 2,
|
|
DM_CAPABILITIES_REPORT = 3,
|
|
DM_CAPABILITIES_RESPONSE = 4,
|
|
DM_STATUS_REPORT = 5,
|
|
DM_BALLOON_REQUEST = 6,
|
|
DM_BALLOON_RESPONSE = 7,
|
|
DM_UNBALLOON_REQUEST = 8,
|
|
DM_UNBALLOON_RESPONSE = 9,
|
|
DM_MEM_HOT_ADD_REQUEST = 10,
|
|
DM_MEM_HOT_ADD_RESPONSE = 11,
|
|
DM_VERSION_03_MAX = 11,
|
|
/*
|
|
* Version 1.0.
|
|
*/
|
|
DM_INFO_MESSAGE = 12,
|
|
DM_VERSION_1_MAX = 12
|
|
};
|
|
|
|
|
|
/*
|
|
* Structures defining the dynamic memory management
|
|
* protocol.
|
|
*/
|
|
|
|
union dm_version {
|
|
struct {
|
|
__u16 minor_version;
|
|
__u16 major_version;
|
|
};
|
|
__u32 version;
|
|
} __packed;
|
|
|
|
|
|
union dm_caps {
|
|
struct {
|
|
__u64 balloon:1;
|
|
__u64 hot_add:1;
|
|
/*
|
|
* To support guests that may have alignment
|
|
* limitations on hot-add, the guest can specify
|
|
* its alignment requirements; a value of n
|
|
* represents an alignment of 2^n in mega bytes.
|
|
*/
|
|
__u64 hot_add_alignment:4;
|
|
__u64 reservedz:58;
|
|
} cap_bits;
|
|
__u64 caps;
|
|
} __packed;
|
|
|
|
union dm_mem_page_range {
|
|
struct {
|
|
/*
|
|
* The PFN number of the first page in the range.
|
|
* 40 bits is the architectural limit of a PFN
|
|
* number for AMD64.
|
|
*/
|
|
__u64 start_page:40;
|
|
/*
|
|
* The number of pages in the range.
|
|
*/
|
|
__u64 page_cnt:24;
|
|
} finfo;
|
|
__u64 page_range;
|
|
} __packed;
|
|
|
|
|
|
|
|
/*
|
|
* The header for all dynamic memory messages:
|
|
*
|
|
* type: Type of the message.
|
|
* size: Size of the message in bytes; including the header.
|
|
* trans_id: The guest is responsible for manufacturing this ID.
|
|
*/
|
|
|
|
struct dm_header {
|
|
__u16 type;
|
|
__u16 size;
|
|
__u32 trans_id;
|
|
} __packed;
|
|
|
|
/*
|
|
* A generic message format for dynamic memory.
|
|
* Specific message formats are defined later in the file.
|
|
*/
|
|
|
|
struct dm_message {
|
|
struct dm_header hdr;
|
|
__u8 data[]; /* enclosed message */
|
|
} __packed;
|
|
|
|
|
|
/*
|
|
* Specific message types supporting the dynamic memory protocol.
|
|
*/
|
|
|
|
/*
|
|
* Version negotiation message. Sent from the guest to the host.
|
|
* The guest is free to try different versions until the host
|
|
* accepts the version.
|
|
*
|
|
* dm_version: The protocol version requested.
|
|
* is_last_attempt: If TRUE, this is the last version guest will request.
|
|
* reservedz: Reserved field, set to zero.
|
|
*/
|
|
|
|
struct dm_version_request {
|
|
struct dm_header hdr;
|
|
union dm_version version;
|
|
__u32 is_last_attempt:1;
|
|
__u32 reservedz:31;
|
|
} __packed;
|
|
|
|
/*
|
|
* Version response message; Host to Guest and indicates
|
|
* if the host has accepted the version sent by the guest.
|
|
*
|
|
* is_accepted: If TRUE, host has accepted the version and the guest
|
|
* should proceed to the next stage of the protocol. FALSE indicates that
|
|
* guest should re-try with a different version.
|
|
*
|
|
* reservedz: Reserved field, set to zero.
|
|
*/
|
|
|
|
struct dm_version_response {
|
|
struct dm_header hdr;
|
|
__u64 is_accepted:1;
|
|
__u64 reservedz:63;
|
|
} __packed;
|
|
|
|
/*
|
|
* Message reporting capabilities. This is sent from the guest to the
|
|
* host.
|
|
*/
|
|
|
|
struct dm_capabilities {
|
|
struct dm_header hdr;
|
|
union dm_caps caps;
|
|
__u64 min_page_cnt;
|
|
__u64 max_page_number;
|
|
} __packed;
|
|
|
|
/*
|
|
* Response to the capabilities message. This is sent from the host to the
|
|
* guest. This message notifies if the host has accepted the guest's
|
|
* capabilities. If the host has not accepted, the guest must shutdown
|
|
* the service.
|
|
*
|
|
* is_accepted: Indicates if the host has accepted guest's capabilities.
|
|
* reservedz: Must be 0.
|
|
*/
|
|
|
|
struct dm_capabilities_resp_msg {
|
|
struct dm_header hdr;
|
|
__u64 is_accepted:1;
|
|
__u64 reservedz:63;
|
|
} __packed;
|
|
|
|
/*
|
|
* This message is used to report memory pressure from the guest.
|
|
* This message is not part of any transaction and there is no
|
|
* response to this message.
|
|
*
|
|
* num_avail: Available memory in pages.
|
|
* num_committed: Committed memory in pages.
|
|
* page_file_size: The accumulated size of all page files
|
|
* in the system in pages.
|
|
* zero_free: The nunber of zero and free pages.
|
|
* page_file_writes: The writes to the page file in pages.
|
|
* io_diff: An indicator of file cache efficiency or page file activity,
|
|
* calculated as File Cache Page Fault Count - Page Read Count.
|
|
* This value is in pages.
|
|
*
|
|
* Some of these metrics are Windows specific and fortunately
|
|
* the algorithm on the host side that computes the guest memory
|
|
* pressure only uses num_committed value.
|
|
*/
|
|
|
|
struct dm_status {
|
|
struct dm_header hdr;
|
|
__u64 num_avail;
|
|
__u64 num_committed;
|
|
__u64 page_file_size;
|
|
__u64 zero_free;
|
|
__u32 page_file_writes;
|
|
__u32 io_diff;
|
|
} __packed;
|
|
|
|
|
|
/*
|
|
* Message to ask the guest to allocate memory - balloon up message.
|
|
* This message is sent from the host to the guest. The guest may not be
|
|
* able to allocate as much memory as requested.
|
|
*
|
|
* num_pages: number of pages to allocate.
|
|
*/
|
|
|
|
struct dm_balloon {
|
|
struct dm_header hdr;
|
|
__u32 num_pages;
|
|
__u32 reservedz;
|
|
} __packed;
|
|
|
|
|
|
/*
|
|
* Balloon response message; this message is sent from the guest
|
|
* to the host in response to the balloon message.
|
|
*
|
|
* reservedz: Reserved; must be set to zero.
|
|
* more_pages: If FALSE, this is the last message of the transaction.
|
|
* if TRUE there will atleast one more message from the guest.
|
|
*
|
|
* range_count: The number of ranges in the range array.
|
|
*
|
|
* range_array: An array of page ranges returned to the host.
|
|
*
|
|
*/
|
|
|
|
struct dm_balloon_response {
|
|
struct dm_header hdr;
|
|
__u32 reservedz;
|
|
__u32 more_pages:1;
|
|
__u32 range_count:31;
|
|
union dm_mem_page_range range_array[];
|
|
} __packed;
|
|
|
|
/*
|
|
* Un-balloon message; this message is sent from the host
|
|
* to the guest to give guest more memory.
|
|
*
|
|
* more_pages: If FALSE, this is the last message of the transaction.
|
|
* if TRUE there will atleast one more message from the guest.
|
|
*
|
|
* reservedz: Reserved; must be set to zero.
|
|
*
|
|
* range_count: The number of ranges in the range array.
|
|
*
|
|
* range_array: An array of page ranges returned to the host.
|
|
*
|
|
*/
|
|
|
|
struct dm_unballoon_request {
|
|
struct dm_header hdr;
|
|
__u32 more_pages:1;
|
|
__u32 reservedz:31;
|
|
__u32 range_count;
|
|
union dm_mem_page_range range_array[];
|
|
} __packed;
|
|
|
|
/*
|
|
* Un-balloon response message; this message is sent from the guest
|
|
* to the host in response to an unballoon request.
|
|
*
|
|
*/
|
|
|
|
struct dm_unballoon_response {
|
|
struct dm_header hdr;
|
|
} __packed;
|
|
|
|
|
|
/*
|
|
* Hot add request message. Message sent from the host to the guest.
|
|
*
|
|
* mem_range: Memory range to hot add.
|
|
*
|
|
* On Linux we currently don't support this since we cannot hot add
|
|
* arbitrary granularity of memory.
|
|
*/
|
|
|
|
struct dm_hot_add {
|
|
struct dm_header hdr;
|
|
union dm_mem_page_range range;
|
|
} __packed;
|
|
|
|
/*
|
|
* Hot add response message.
|
|
* This message is sent by the guest to report the status of a hot add request.
|
|
* If page_count is less than the requested page count, then the host should
|
|
* assume all further hot add requests will fail, since this indicates that
|
|
* the guest has hit an upper physical memory barrier.
|
|
*
|
|
* Hot adds may also fail due to low resources; in this case, the guest must
|
|
* not complete this message until the hot add can succeed, and the host must
|
|
* not send a new hot add request until the response is sent.
|
|
* If VSC fails to hot add memory DYNMEM_NUMBER_OF_UNSUCCESSFUL_HOTADD_ATTEMPTS
|
|
* times it fails the request.
|
|
*
|
|
*
|
|
* page_count: number of pages that were successfully hot added.
|
|
*
|
|
* result: result of the operation 1: success, 0: failure.
|
|
*
|
|
*/
|
|
|
|
struct dm_hot_add_response {
|
|
struct dm_header hdr;
|
|
__u32 page_count;
|
|
__u32 result;
|
|
} __packed;
|
|
|
|
/*
|
|
* Types of information sent from host to the guest.
|
|
*/
|
|
|
|
enum dm_info_type {
|
|
INFO_TYPE_MAX_PAGE_CNT = 0,
|
|
MAX_INFO_TYPE
|
|
};
|
|
|
|
|
|
/*
|
|
* Header for the information message.
|
|
*/
|
|
|
|
struct dm_info_header {
|
|
enum dm_info_type type;
|
|
__u32 data_size;
|
|
} __packed;
|
|
|
|
/*
|
|
* This message is sent from the host to the guest to pass
|
|
* some relevant information (win8 addition).
|
|
*
|
|
* reserved: no used.
|
|
* info_size: size of the information blob.
|
|
* info: information blob.
|
|
*/
|
|
|
|
struct dm_info_msg {
|
|
struct dm_header hdr;
|
|
__u32 reserved;
|
|
__u32 info_size;
|
|
__u8 info[];
|
|
};
|
|
|
|
/*
|
|
* End protocol definitions.
|
|
*/
|
|
|
|
/*
|
|
* State to manage hot adding memory into the guest.
|
|
* The range start_pfn : end_pfn specifies the range
|
|
* that the host has asked us to hot add. The range
|
|
* start_pfn : ha_end_pfn specifies the range that we have
|
|
* currently hot added. We hot add in multiples of 128M
|
|
* chunks; it is possible that we may not be able to bring
|
|
* online all the pages in the region. The range
|
|
* covered_start_pfn : covered_end_pfn defines the pages that can
|
|
* be brough online.
|
|
*/
|
|
|
|
struct hv_hotadd_state {
|
|
struct list_head list;
|
|
unsigned long start_pfn;
|
|
unsigned long covered_start_pfn;
|
|
unsigned long covered_end_pfn;
|
|
unsigned long ha_end_pfn;
|
|
unsigned long end_pfn;
|
|
};
|
|
|
|
struct balloon_state {
|
|
__u32 num_pages;
|
|
struct work_struct wrk;
|
|
};
|
|
|
|
struct hot_add_wrk {
|
|
union dm_mem_page_range ha_page_range;
|
|
union dm_mem_page_range ha_region_range;
|
|
struct work_struct wrk;
|
|
};
|
|
|
|
static bool hot_add = true;
|
|
static bool do_hot_add;
|
|
/*
|
|
* Delay reporting memory pressure by
|
|
* the specified number of seconds.
|
|
*/
|
|
static uint pressure_report_delay = 45;
|
|
|
|
module_param(hot_add, bool, (S_IRUGO | S_IWUSR));
|
|
MODULE_PARM_DESC(hot_add, "If set attempt memory hot_add");
|
|
|
|
module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR));
|
|
MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure");
|
|
static atomic_t trans_id = ATOMIC_INIT(0);
|
|
|
|
static int dm_ring_size = (5 * PAGE_SIZE);
|
|
|
|
/*
|
|
* Driver specific state.
|
|
*/
|
|
|
|
enum hv_dm_state {
|
|
DM_INITIALIZING = 0,
|
|
DM_INITIALIZED,
|
|
DM_BALLOON_UP,
|
|
DM_BALLOON_DOWN,
|
|
DM_HOT_ADD,
|
|
DM_INIT_ERROR
|
|
};
|
|
|
|
|
|
static __u8 recv_buffer[PAGE_SIZE];
|
|
static __u8 *send_buffer;
|
|
#define PAGES_IN_2M 512
|
|
#define HA_CHUNK (32 * 1024)
|
|
|
|
struct hv_dynmem_device {
|
|
struct hv_device *dev;
|
|
enum hv_dm_state state;
|
|
struct completion host_event;
|
|
struct completion config_event;
|
|
|
|
/*
|
|
* Number of pages we have currently ballooned out.
|
|
*/
|
|
unsigned int num_pages_ballooned;
|
|
|
|
/*
|
|
* State to manage the ballooning (up) operation.
|
|
*/
|
|
struct balloon_state balloon_wrk;
|
|
|
|
/*
|
|
* State to execute the "hot-add" operation.
|
|
*/
|
|
struct hot_add_wrk ha_wrk;
|
|
|
|
/*
|
|
* This state tracks if the host has specified a hot-add
|
|
* region.
|
|
*/
|
|
bool host_specified_ha_region;
|
|
|
|
/*
|
|
* State to synchronize hot-add.
|
|
*/
|
|
struct completion ol_waitevent;
|
|
bool ha_waiting;
|
|
/*
|
|
* This thread handles hot-add
|
|
* requests from the host as well as notifying
|
|
* the host with regards to memory pressure in
|
|
* the guest.
|
|
*/
|
|
struct task_struct *thread;
|
|
|
|
/*
|
|
* A list of hot-add regions.
|
|
*/
|
|
struct list_head ha_region_list;
|
|
|
|
/*
|
|
* We start with the highest version we can support
|
|
* and downgrade based on the host; we save here the
|
|
* next version to try.
|
|
*/
|
|
__u32 next_version;
|
|
};
|
|
|
|
static struct hv_dynmem_device dm_device;
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
|
|
static void hv_bring_pgs_online(unsigned long start_pfn, unsigned long size)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < size; i++) {
|
|
struct page *pg;
|
|
pg = pfn_to_page(start_pfn + i);
|
|
__online_page_set_limits(pg);
|
|
__online_page_increment_counters(pg);
|
|
__online_page_free(pg);
|
|
}
|
|
}
|
|
|
|
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, t;
|
|
unsigned long start_pfn;
|
|
unsigned long processed_pfn;
|
|
unsigned long total_pfn = pfn_count;
|
|
|
|
for (i = 0; i < (size/HA_CHUNK); i++) {
|
|
start_pfn = start + (i * HA_CHUNK);
|
|
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;
|
|
|
|
init_completion(&dm_device.ol_waitevent);
|
|
dm_device.ha_waiting = true;
|
|
|
|
nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn));
|
|
ret = add_memory(nid, PFN_PHYS((start_pfn)),
|
|
(HA_CHUNK << PAGE_SHIFT));
|
|
|
|
if (ret) {
|
|
pr_info("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;
|
|
}
|
|
has->ha_end_pfn -= HA_CHUNK;
|
|
has->covered_end_pfn -= processed_pfn;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Wait for the memory block to be onlined.
|
|
*/
|
|
t = wait_for_completion_timeout(&dm_device.ol_waitevent, 5*HZ);
|
|
if (t == 0) {
|
|
pr_info("hot_add memory timedout\n");
|
|
has->ha_end_pfn -= HA_CHUNK;
|
|
has->covered_end_pfn -= processed_pfn;
|
|
break;
|
|
}
|
|
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
static void hv_online_page(struct page *pg)
|
|
{
|
|
struct list_head *cur;
|
|
struct hv_hotadd_state *has;
|
|
unsigned long cur_start_pgp;
|
|
unsigned long cur_end_pgp;
|
|
|
|
if (dm_device.ha_waiting) {
|
|
dm_device.ha_waiting = false;
|
|
complete(&dm_device.ol_waitevent);
|
|
}
|
|
|
|
list_for_each(cur, &dm_device.ha_region_list) {
|
|
has = list_entry(cur, struct hv_hotadd_state, list);
|
|
cur_start_pgp = (unsigned long)
|
|
pfn_to_page(has->covered_start_pfn);
|
|
cur_end_pgp = (unsigned long)pfn_to_page(has->covered_end_pfn);
|
|
|
|
if (((unsigned long)pg >= cur_start_pgp) &&
|
|
((unsigned long)pg < cur_end_pgp)) {
|
|
/*
|
|
* This frame is currently backed; online the
|
|
* page.
|
|
*/
|
|
__online_page_set_limits(pg);
|
|
__online_page_increment_counters(pg);
|
|
__online_page_free(pg);
|
|
has->covered_start_pfn++;
|
|
}
|
|
}
|
|
}
|
|
|
|
static bool pfn_covered(unsigned long start_pfn, unsigned long pfn_cnt)
|
|
{
|
|
struct list_head *cur;
|
|
struct hv_hotadd_state *has;
|
|
unsigned long residual, new_inc;
|
|
|
|
if (list_empty(&dm_device.ha_region_list))
|
|
return false;
|
|
|
|
list_for_each(cur, &dm_device.ha_region_list) {
|
|
has = list_entry(cur, struct hv_hotadd_state, list);
|
|
|
|
/*
|
|
* If the pfn range we are dealing with is not in the current
|
|
* "hot add block", move on.
|
|
*/
|
|
if ((start_pfn >= has->end_pfn))
|
|
continue;
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/*
|
|
* If the current start pfn is not where the covered_end
|
|
* is, update it.
|
|
*/
|
|
|
|
if (has->covered_end_pfn != start_pfn) {
|
|
has->covered_end_pfn = start_pfn;
|
|
has->covered_start_pfn = start_pfn;
|
|
}
|
|
return true;
|
|
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
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 list_head *cur;
|
|
struct hv_hotadd_state *has;
|
|
unsigned long pgs_ol = 0;
|
|
unsigned long old_covered_state;
|
|
|
|
if (list_empty(&dm_device.ha_region_list))
|
|
return 0;
|
|
|
|
list_for_each(cur, &dm_device.ha_region_list) {
|
|
has = list_entry(cur, struct hv_hotadd_state, list);
|
|
|
|
/*
|
|
* If the pfn range we are dealing with is not in the current
|
|
* "hot add block", move on.
|
|
*/
|
|
if ((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;
|
|
hv_bring_pgs_online(start_pfn, pgs_ol);
|
|
has->covered_end_pfn += pgs_ol;
|
|
has->covered_start_pfn += pgs_ol;
|
|
pfn_cnt -= 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;
|
|
}
|
|
hv_mem_hot_add(has->ha_end_pfn, size, pfn_cnt, has);
|
|
}
|
|
/*
|
|
* If we managed to online any pages that were given to us,
|
|
* we declare success.
|
|
*/
|
|
return has->covered_end_pfn - old_covered_state;
|
|
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
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;
|
|
|
|
if (pfn_cnt == 0)
|
|
return 0;
|
|
|
|
if (!dm_device.host_specified_ha_region)
|
|
if (pfn_covered(pg_start, pfn_cnt))
|
|
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);
|
|
|
|
list_add_tail(&ha_region->list, &dm_device.ha_region_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;
|
|
}
|
|
|
|
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);
|
|
resp.hdr.trans_id = atomic_inc_return(&trans_id);
|
|
|
|
#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_start = pg_start;
|
|
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);
|
|
#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))
|
|
pr_info("Memory hot add failed\n");
|
|
|
|
dm->state = DM_INITIALIZED;
|
|
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:
|
|
pr_info("Received INFO_TYPE_MAX_PAGE_CNT\n");
|
|
pr_info("Data Size is %d\n", info_hdr->data_size);
|
|
break;
|
|
default:
|
|
pr_info("Received Unknown type: %d\n", info_hdr->type);
|
|
}
|
|
}
|
|
|
|
static unsigned long compute_balloon_floor(void)
|
|
{
|
|
unsigned long min_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 552 (1/32)
|
|
* 32768 1320
|
|
* 131072 4392
|
|
*/
|
|
if (totalram_pages < MB2PAGES(128))
|
|
min_pages = MB2PAGES(8) + (totalram_pages >> 1);
|
|
else if (totalram_pages < MB2PAGES(512))
|
|
min_pages = MB2PAGES(40) + (totalram_pages >> 2);
|
|
else if (totalram_pages < MB2PAGES(2048))
|
|
min_pages = MB2PAGES(104) + (totalram_pages >> 3);
|
|
else
|
|
min_pages = MB2PAGES(296) + (totalram_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;
|
|
struct sysinfo val;
|
|
|
|
if (pressure_report_delay > 0) {
|
|
--pressure_report_delay;
|
|
return;
|
|
}
|
|
si_meminfo(&val);
|
|
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 memory.
|
|
* Further, 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.
|
|
*/
|
|
status.num_avail = val.freeram;
|
|
status.num_committed = vm_memory_committed() +
|
|
dm->num_pages_ballooned +
|
|
compute_balloon_floor();
|
|
|
|
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);
|
|
__free_page(pg);
|
|
dm->num_pages_ballooned--;
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static int alloc_balloon_pages(struct hv_dynmem_device *dm, int num_pages,
|
|
struct dm_balloon_response *bl_resp, int alloc_unit,
|
|
bool *alloc_error)
|
|
{
|
|
int i = 0;
|
|
struct page *pg;
|
|
|
|
if (num_pages < alloc_unit)
|
|
return 0;
|
|
|
|
for (i = 0; (i * alloc_unit) < num_pages; i++) {
|
|
if (bl_resp->hdr.size + sizeof(union dm_mem_page_range) >
|
|
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) {
|
|
*alloc_error = true;
|
|
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));
|
|
|
|
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 num_pages;
|
|
}
|
|
|
|
|
|
|
|
static void balloon_up(struct work_struct *dummy)
|
|
{
|
|
int num_pages = dm_device.balloon_wrk.num_pages;
|
|
int num_ballooned = 0;
|
|
struct dm_balloon_response *bl_resp;
|
|
int alloc_unit;
|
|
int ret;
|
|
bool alloc_error = false;
|
|
bool done = false;
|
|
int i;
|
|
|
|
|
|
/*
|
|
* We will attempt 2M allocations. However, if we fail to
|
|
* allocate 2M chunks, we will go back to 4k allocations.
|
|
*/
|
|
alloc_unit = 512;
|
|
|
|
while (!done) {
|
|
bl_resp = (struct dm_balloon_response *)send_buffer;
|
|
memset(send_buffer, 0, PAGE_SIZE);
|
|
bl_resp->hdr.type = DM_BALLOON_RESPONSE;
|
|
bl_resp->hdr.trans_id = atomic_inc_return(&trans_id);
|
|
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,
|
|
&alloc_error);
|
|
|
|
if ((alloc_error) && (alloc_unit != 1)) {
|
|
alloc_unit = 1;
|
|
continue;
|
|
}
|
|
|
|
if ((alloc_error) || (num_ballooned == 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 {
|
|
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);
|
|
|
|
} while (ret == -EAGAIN);
|
|
|
|
if (ret) {
|
|
/*
|
|
* Free up the memory we allocatted.
|
|
*/
|
|
pr_info("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;
|
|
|
|
for (i = 0; i < range_count; i++)
|
|
free_balloon_pages(dm, &range_array[i]);
|
|
|
|
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;
|
|
int t;
|
|
|
|
while (!kthread_should_stop()) {
|
|
t = wait_for_completion_timeout(&dm_device.config_event, 1*HZ);
|
|
/*
|
|
* The host expects us to post information on the memory
|
|
* pressure every second.
|
|
*/
|
|
|
|
if (t == 0)
|
|
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;
|
|
|
|
dm->next_version = 0;
|
|
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_WIN7;
|
|
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_info("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,
|
|
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 (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:
|
|
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.
|
|
*/
|
|
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_err("Unhandled message: type: %d\n", dm_hdr->type);
|
|
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
static int balloon_probe(struct hv_device *dev,
|
|
const struct hv_vmbus_device_id *dev_id)
|
|
{
|
|
int ret, t;
|
|
struct dm_version_request version_req;
|
|
struct dm_capabilities cap_msg;
|
|
|
|
do_hot_add = hot_add;
|
|
|
|
/*
|
|
* First allocate a send buffer.
|
|
*/
|
|
|
|
send_buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
|
|
if (!send_buffer)
|
|
return -ENOMEM;
|
|
|
|
ret = vmbus_open(dev->channel, dm_ring_size, dm_ring_size, NULL, 0,
|
|
balloon_onchannelcallback, dev);
|
|
|
|
if (ret)
|
|
goto probe_error0;
|
|
|
|
dm_device.dev = dev;
|
|
dm_device.state = DM_INITIALIZING;
|
|
dm_device.next_version = DYNMEM_PROTOCOL_VERSION_WIN7;
|
|
init_completion(&dm_device.host_event);
|
|
init_completion(&dm_device.config_event);
|
|
INIT_LIST_HEAD(&dm_device.ha_region_list);
|
|
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;
|
|
|
|
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_error1;
|
|
}
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
set_online_page_callback(&hv_online_page);
|
|
#endif
|
|
|
|
hv_set_drvdata(dev, &dm_device);
|
|
/*
|
|
* 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_WIN8;
|
|
version_req.is_last_attempt = 0;
|
|
|
|
ret = vmbus_sendpacket(dev->channel, &version_req,
|
|
sizeof(struct dm_version_request),
|
|
(unsigned long)NULL,
|
|
VM_PKT_DATA_INBAND, 0);
|
|
if (ret)
|
|
goto probe_error2;
|
|
|
|
t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ);
|
|
if (t == 0) {
|
|
ret = -ETIMEDOUT;
|
|
goto probe_error2;
|
|
}
|
|
|
|
/*
|
|
* If we could not negotiate a compatible version with the host
|
|
* fail the probe function.
|
|
*/
|
|
if (dm_device.state == DM_INIT_ERROR) {
|
|
ret = -ETIMEDOUT;
|
|
goto probe_error2;
|
|
}
|
|
/*
|
|
* 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);
|
|
|
|
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 probe_error2;
|
|
|
|
t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ);
|
|
if (t == 0) {
|
|
ret = -ETIMEDOUT;
|
|
goto probe_error2;
|
|
}
|
|
|
|
/*
|
|
* If the host does not like our capabilities,
|
|
* fail the probe function.
|
|
*/
|
|
if (dm_device.state == DM_INIT_ERROR) {
|
|
ret = -ETIMEDOUT;
|
|
goto probe_error2;
|
|
}
|
|
|
|
dm_device.state = DM_INITIALIZED;
|
|
|
|
return 0;
|
|
|
|
probe_error2:
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
restore_online_page_callback(&hv_online_page);
|
|
#endif
|
|
kthread_stop(dm_device.thread);
|
|
|
|
probe_error1:
|
|
vmbus_close(dev->channel);
|
|
probe_error0:
|
|
kfree(send_buffer);
|
|
return ret;
|
|
}
|
|
|
|
static int balloon_remove(struct hv_device *dev)
|
|
{
|
|
struct hv_dynmem_device *dm = hv_get_drvdata(dev);
|
|
struct list_head *cur, *tmp;
|
|
struct hv_hotadd_state *has;
|
|
|
|
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);
|
|
|
|
vmbus_close(dev->channel);
|
|
kthread_stop(dm->thread);
|
|
kfree(send_buffer);
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
restore_online_page_callback(&hv_online_page);
|
|
#endif
|
|
list_for_each_safe(cur, tmp, &dm->ha_region_list) {
|
|
has = list_entry(cur, struct hv_hotadd_state, list);
|
|
list_del(&has->list);
|
|
kfree(has);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
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,
|
|
};
|
|
|
|
static int __init init_balloon_drv(void)
|
|
{
|
|
|
|
return vmbus_driver_register(&balloon_drv);
|
|
}
|
|
|
|
module_init(init_balloon_drv);
|
|
|
|
MODULE_DESCRIPTION("Hyper-V Balloon");
|
|
MODULE_VERSION(HV_DRV_VERSION);
|
|
MODULE_LICENSE("GPL");
|