*/
#include "qemu/osdep.h"
-
-#include "qemu-common.h"
-#include "migration/migration.h"
-#include "migration/postcopy-ram.h"
+#include "exec/target_page.h"
+#include "migration.h"
+#include "qemu-file.h"
+#include "savevm.h"
+#include "postcopy-ram.h"
+#include "ram.h"
#include "sysemu/sysemu.h"
#include "sysemu/balloon.h"
#include "qemu/error-report.h"
struct PostcopyDiscardState {
const char *ramblock_name;
- uint64_t offset; /* Bitmap entry for the 1st bit of this RAMBlock */
uint16_t cur_entry;
/*
* Start and length of a discard range (bytes)
return false;
}
+ if (getpagesize() != ram_pagesize_summary()) {
+ bool have_hp = false;
+ /* We've got a huge page */
+#ifdef UFFD_FEATURE_MISSING_HUGETLBFS
+ have_hp = api_struct.features & UFFD_FEATURE_MISSING_HUGETLBFS;
+#endif
+ if (!have_hp) {
+ error_report("Userfault on this host does not support huge pages");
+ return false;
+ }
+ }
return true;
}
-/*
- * Check for things that postcopy won't support; returns 0 if the block
- * is fine.
+/* Callback from postcopy_ram_supported_by_host block iterator.
*/
-static int check_range(const char *block_name, void *host_addr,
- ram_addr_t offset, ram_addr_t length, void *opaque)
+static int test_ramblock_postcopiable(const char *block_name, void *host_addr,
+ ram_addr_t offset, ram_addr_t length, void *opaque)
{
RAMBlock *rb = qemu_ram_block_by_name(block_name);
+ size_t pagesize = qemu_ram_pagesize(rb);
- if (qemu_ram_pagesize(rb) > getpagesize()) {
- error_report("Postcopy doesn't support large page sizes yet (%s)",
+ if (qemu_ram_is_shared(rb)) {
+ error_report("Postcopy on shared RAM (%s) is not yet supported",
block_name);
- return -E2BIG;
+ return 1;
}
+ if (length % pagesize) {
+ error_report("Postcopy requires RAM blocks to be a page size multiple,"
+ " block %s is 0x" RAM_ADDR_FMT " bytes with a "
+ "page size of 0x%zx", block_name, length, pagesize);
+ return 1;
+ }
return 0;
}
struct uffdio_range range_struct;
uint64_t feature_mask;
- if ((1ul << qemu_target_page_bits()) > pagesize) {
+ if (qemu_target_page_size() > pagesize) {
error_report("Target page size bigger than host page size");
goto out;
}
- /* Check for anything about the RAMBlocks we don't support */
- if (qemu_ram_foreach_block(check_range, NULL)) {
- /* check_range will have printed its own error */
- goto out;
- }
-
ufd = syscall(__NR_userfaultfd, O_CLOEXEC);
if (ufd == -1) {
error_report("%s: userfaultfd not available: %s", __func__,
goto out;
}
+ /* We don't support postcopy with shared RAM yet */
+ if (qemu_ram_foreach_block(test_ramblock_postcopiable, NULL)) {
+ goto out;
+ }
+
/*
* userfault and mlock don't go together; we'll put it back later if
* it was enabled.
return ret;
}
-/**
- * postcopy_ram_discard_range: Discard a range of memory.
- * We can assume that if we've been called postcopy_ram_hosttest returned true.
- *
- * @mis: Current incoming migration state.
- * @start, @length: range of memory to discard.
- *
- * returns: 0 on success.
- */
-int postcopy_ram_discard_range(MigrationIncomingState *mis, uint8_t *start,
- size_t length)
-{
- trace_postcopy_ram_discard_range(start, length);
- if (madvise(start, length, MADV_DONTNEED)) {
- error_report("%s MADV_DONTNEED: %s", __func__, strerror(errno));
- return -1;
- }
-
- return 0;
-}
-
/*
* Setup an area of RAM so that it *can* be used for postcopy later; this
* must be done right at the start prior to pre-copy.
static int init_range(const char *block_name, void *host_addr,
ram_addr_t offset, ram_addr_t length, void *opaque)
{
- MigrationIncomingState *mis = opaque;
-
trace_postcopy_init_range(block_name, host_addr, offset, length);
/*
* - we're going to get the copy from the source anyway.
* (Precopy will just overwrite this data, so doesn't need the discard)
*/
- if (postcopy_ram_discard_range(mis, host_addr, length)) {
+ if (ram_discard_range(block_name, 0, length)) {
return -1;
}
*/
int postcopy_ram_incoming_init(MigrationIncomingState *mis, size_t ram_pages)
{
- if (qemu_ram_foreach_block(init_range, mis)) {
+ if (qemu_ram_foreach_block(init_range, NULL)) {
return -1;
}
}
postcopy_state_set(POSTCOPY_INCOMING_END);
- migrate_send_rp_shut(mis, qemu_file_get_error(mis->from_src_file) != 0);
if (mis->postcopy_tmp_page) {
- munmap(mis->postcopy_tmp_page, getpagesize());
+ munmap(mis->postcopy_tmp_page, mis->largest_page_size);
mis->postcopy_tmp_page = NULL;
}
+ if (mis->postcopy_tmp_zero_page) {
+ munmap(mis->postcopy_tmp_zero_page, mis->largest_page_size);
+ mis->postcopy_tmp_zero_page = NULL;
+ }
trace_postcopy_ram_incoming_cleanup_exit();
return 0;
}
error_report("%s userfault register: %s", __func__, strerror(errno));
return -1;
}
+ if (!(reg_struct.ioctls & ((__u64)1 << _UFFDIO_COPY))) {
+ error_report("%s userfault: Region doesn't support COPY", __func__);
+ return -1;
+ }
return 0;
}
MigrationIncomingState *mis = opaque;
struct uffd_msg msg;
int ret;
- size_t hostpagesize = getpagesize();
RAMBlock *rb = NULL;
RAMBlock *last_rb = NULL; /* last RAMBlock we sent part of */
break;
}
- rb_offset &= ~(hostpagesize - 1);
+ rb_offset &= ~(qemu_ram_pagesize(rb) - 1);
trace_postcopy_ram_fault_thread_request(msg.arg.pagefault.address,
qemu_ram_get_idstr(rb),
rb_offset);
if (rb != last_rb) {
last_rb = rb;
migrate_send_rp_req_pages(mis, qemu_ram_get_idstr(rb),
- rb_offset, hostpagesize);
+ rb_offset, qemu_ram_pagesize(rb));
} else {
/* Save some space */
migrate_send_rp_req_pages(mis, NULL,
- rb_offset, hostpagesize);
+ rb_offset, qemu_ram_pagesize(rb));
}
}
trace_postcopy_ram_fault_thread_exit();
* Place a host page (from) at (host) atomically
* returns 0 on success
*/
-int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from)
+int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
+ size_t pagesize)
{
struct uffdio_copy copy_struct;
copy_struct.dst = (uint64_t)(uintptr_t)host;
copy_struct.src = (uint64_t)(uintptr_t)from;
- copy_struct.len = getpagesize();
+ copy_struct.len = pagesize;
copy_struct.mode = 0;
/* copy also acks to the kernel waking the stalled thread up
*/
if (ioctl(mis->userfault_fd, UFFDIO_COPY, ©_struct)) {
int e = errno;
- error_report("%s: %s copy host: %p from: %p",
- __func__, strerror(e), host, from);
+ error_report("%s: %s copy host: %p from: %p (size: %zd)",
+ __func__, strerror(e), host, from, pagesize);
return -e;
}
* Place a zero page at (host) atomically
* returns 0 on success
*/
-int postcopy_place_page_zero(MigrationIncomingState *mis, void *host)
+int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
+ size_t pagesize)
{
- struct uffdio_zeropage zero_struct;
+ trace_postcopy_place_page_zero(host);
- zero_struct.range.start = (uint64_t)(uintptr_t)host;
- zero_struct.range.len = getpagesize();
- zero_struct.mode = 0;
+ if (pagesize == getpagesize()) {
+ struct uffdio_zeropage zero_struct;
+ zero_struct.range.start = (uint64_t)(uintptr_t)host;
+ zero_struct.range.len = getpagesize();
+ zero_struct.mode = 0;
- if (ioctl(mis->userfault_fd, UFFDIO_ZEROPAGE, &zero_struct)) {
- int e = errno;
- error_report("%s: %s zero host: %p",
- __func__, strerror(e), host);
+ if (ioctl(mis->userfault_fd, UFFDIO_ZEROPAGE, &zero_struct)) {
+ int e = errno;
+ error_report("%s: %s zero host: %p",
+ __func__, strerror(e), host);
- return -e;
+ return -e;
+ }
+ } else {
+ /* The kernel can't use UFFDIO_ZEROPAGE for hugepages */
+ if (!mis->postcopy_tmp_zero_page) {
+ mis->postcopy_tmp_zero_page = mmap(NULL, mis->largest_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ -1, 0);
+ if (mis->postcopy_tmp_zero_page == MAP_FAILED) {
+ int e = errno;
+ mis->postcopy_tmp_zero_page = NULL;
+ error_report("%s: %s mapping large zero page",
+ __func__, strerror(e));
+ return -e;
+ }
+ memset(mis->postcopy_tmp_zero_page, '\0', mis->largest_page_size);
+ }
+ return postcopy_place_page(mis, host, mis->postcopy_tmp_zero_page,
+ pagesize);
}
- trace_postcopy_place_page_zero(host);
return 0;
}
void *postcopy_get_tmp_page(MigrationIncomingState *mis)
{
if (!mis->postcopy_tmp_page) {
- mis->postcopy_tmp_page = mmap(NULL, getpagesize(),
+ mis->postcopy_tmp_page = mmap(NULL, mis->largest_page_size,
PROT_READ | PROT_WRITE, MAP_PRIVATE |
MAP_ANONYMOUS, -1, 0);
if (mis->postcopy_tmp_page == MAP_FAILED) {
return -1;
}
-int postcopy_ram_discard_range(MigrationIncomingState *mis, uint8_t *start,
- size_t length)
-{
- assert(0);
- return -1;
-}
-
int postcopy_ram_prepare_discard(MigrationIncomingState *mis)
{
assert(0);
return -1;
}
-int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from)
+int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
+ size_t pagesize)
{
assert(0);
return -1;
}
-int postcopy_place_page_zero(MigrationIncomingState *mis, void *host)
+int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
+ size_t pagesize)
{
assert(0);
return -1;
* returns: a new PDS.
*/
PostcopyDiscardState *postcopy_discard_send_init(MigrationState *ms,
- unsigned long offset,
const char *name)
{
PostcopyDiscardState *res = g_malloc0(sizeof(PostcopyDiscardState));
if (res) {
res->ramblock_name = name;
- res->offset = offset;
}
return res;
void postcopy_discard_send_range(MigrationState *ms, PostcopyDiscardState *pds,
unsigned long start, unsigned long length)
{
- size_t tp_bits = qemu_target_page_bits();
+ size_t tp_size = qemu_target_page_size();
/* Convert to byte offsets within the RAM block */
- pds->start_list[pds->cur_entry] = (start - pds->offset) << tp_bits;
- pds->length_list[pds->cur_entry] = length << tp_bits;
+ pds->start_list[pds->cur_entry] = start * tp_size;
+ pds->length_list[pds->cur_entry] = length * tp_size;
trace_postcopy_discard_send_range(pds->ramblock_name, start, length);
pds->cur_entry++;
pds->nsentwords++;
g_free(pds);
}
+
+/*
+ * Current state of incoming postcopy; note this is not part of
+ * MigrationIncomingState since it's state is used during cleanup
+ * at the end as MIS is being freed.
+ */
+static PostcopyState incoming_postcopy_state;
+
+PostcopyState postcopy_state_get(void)
+{
+ return atomic_mb_read(&incoming_postcopy_state);
+}
+
+/* Set the state and return the old state */
+PostcopyState postcopy_state_set(PostcopyState new_state)
+{
+ return atomic_xchg(&incoming_postcopy_state, new_state);
+}
projects / qemu.git / blobdiff