// SPDX-License-Identifier: GPL-2.0
/*
* HMM stands for Heterogeneous Memory Management, it is a helper layer inside
* the linux kernel to help device drivers mirror a process address space in
* the device. This allows the device to use the same address space which
* makes communication and data exchange a lot easier.
*
* This framework's sole purpose is to exercise various code paths inside
* the kernel to make sure that HMM performs as expected and to flush out any
* bugs.
*/
#include "../kselftest_harness.h"
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <strings.h>
#include <time.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
/*
* This is a private UAPI to the kernel test module so it isn't exported
* in the usual include/uapi/... directory.
*/
#include <lib/test_hmm_uapi.h>
#include <mm/gup_test.h>
struct hmm_buffer {
void *ptr;
void *mirror;
unsigned long size;
int fd;
uint64_t cpages;
uint64_t faults;
};
enum {
HMM_PRIVATE_DEVICE_ONE,
HMM_PRIVATE_DEVICE_TWO,
HMM_COHERENCE_DEVICE_ONE,
HMM_COHERENCE_DEVICE_TWO,
};
#define TWOMEG (1 << 21)
#define HMM_BUFFER_SIZE (1024 << 12)
#define HMM_PATH_MAX 64
#define NTIMES 10
#define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1)))
/* Just the flags we need, copied from mm.h: */
#ifndef FOLL_WRITE
#define FOLL_WRITE 0x01 /* check pte is writable */
#endif
#ifndef FOLL_LONGTERM
#define FOLL_LONGTERM 0x100 /* mapping lifetime is indefinite */
#endif
FIXTURE(hmm)
{
int fd;
unsigned int page_size;
unsigned int page_shift;
};
FIXTURE_VARIANT(hmm)
{
int device_number;
};
FIXTURE_VARIANT_ADD(hmm, hmm_device_private)
{
.device_number = HMM_PRIVATE_DEVICE_ONE,
};
FIXTURE_VARIANT_ADD(hmm, hmm_device_coherent)
{
.device_number = HMM_COHERENCE_DEVICE_ONE,
};
FIXTURE(hmm2)
{
int fd0;
int fd1;
unsigned int page_size;
unsigned int page_shift;
};
FIXTURE_VARIANT(hmm2)
{
int device_number0;
int device_number1;
};
FIXTURE_VARIANT_ADD(hmm2, hmm2_device_private)
{
.device_number0 = HMM_PRIVATE_DEVICE_ONE,
.device_number1 = HMM_PRIVATE_DEVICE_TWO,
};
FIXTURE_VARIANT_ADD(hmm2, hmm2_device_coherent)
{
.device_number0 = HMM_COHERENCE_DEVICE_ONE,
.device_number1 = HMM_COHERENCE_DEVICE_TWO,
};
static int hmm_open(int unit)
{
char pathname[HMM_PATH_MAX];
int fd;
snprintf(pathname, sizeof(pathname), "/dev/hmm_dmirror%d", unit);
fd = open(pathname, O_RDWR, 0);
if (fd < 0)
fprintf(stderr, "could not open hmm dmirror driver (%s)\n",
pathname);
return fd;
}
static bool hmm_is_coherent_type(int dev_num)
{
return (dev_num >= HMM_COHERENCE_DEVICE_ONE);
}
FIXTURE_SETUP(hmm)
{
self->page_size = sysconf(_SC_PAGE_SIZE);
self->page_shift = ffs(self->page_size) - 1;
self->fd = hmm_open(variant->device_number);
if (self->fd < 0 && hmm_is_coherent_type(variant->device_number))
SKIP(return, "DEVICE_COHERENT not available");
ASSERT_GE(self->fd, 0);
}
FIXTURE_SETUP(hmm2)
{
self->page_size = sysconf(_SC_PAGE_SIZE);
self->page_shift = ffs(self->page_size) - 1;
self->fd0 = hmm_open(variant->device_number0);
if (self->fd0 < 0 && hmm_is_coherent_type(variant->device_number0))
SKIP(return, "DEVICE_COHERENT not available");
ASSERT_GE(self->fd0, 0);
self->fd1 = hmm_open(variant->device_number1);
ASSERT_GE(self->fd1, 0);
}
FIXTURE_TEARDOWN(hmm)
{
int ret = close(self->fd);
ASSERT_EQ(ret, 0);
self->fd = -1;
}
FIXTURE_TEARDOWN(hmm2)
{
int ret = close(self->fd0);
ASSERT_EQ(ret, 0);
self->fd0 = -1;
ret = close(self->fd1);
ASSERT_EQ(ret, 0);
self->fd1 = -1;
}
static int hmm_dmirror_cmd(int fd,
unsigned long request,
struct hmm_buffer *buffer,
unsigned long npages)
{
struct hmm_dmirror_cmd cmd;
int ret;
/* Simulate a device reading system memory. */
cmd.addr = (__u64)buffer->ptr;
cmd.ptr = (__u64)buffer->mirror;
cmd.npages = npages;
for (;;) {
ret = ioctl(fd, request, &cmd);
if (ret == 0)
break;
if (errno == EINTR)
continue;
return -errno;
}
buffer->cpages = cmd.cpages;
buffer->faults = cmd.faults;
return 0;
}
static void hmm_buffer_free(struct hmm_buffer *buffer)
{
if (buffer == NULL)
return;
if (buffer->ptr)
munmap(buffer->ptr, buffer->size);
free(buffer->mirror);
free(buffer);
}
/*
* Create a temporary file that will be deleted on close.
*/
static int hmm_create_file(unsigned long size)
{
char path[HMM_PATH_MAX];
int fd;
strcpy(path, "/tmp");
fd = open(path, O_TMPFILE | O_EXCL | O_RDWR, 0600);
if (fd >= 0) {
int r;
do {
r = ftruncate(fd, size);
} while (r == -1 && errno == EINTR);
if (!r)
return fd;
close(fd);
}
return -1;
}
/*
* Return a random unsigned number.
*/
static unsigned int hmm_random(void)
{
static int fd = -1;
unsigned int r;
if (fd < 0) {
fd = open("/dev/urandom", O_RDONLY);
if (fd < 0) {
fprintf(stderr, "%s:%d failed to open /dev/urandom\n",
__FILE__, __LINE__);
return ~0U;
}
}
read(fd, &r, sizeof(r));
return r;
}
static void hmm_nanosleep(unsigned int n)
{
struct timespec t;
t.tv_sec = 0;
t.tv_nsec = n;
nanosleep(&t, NULL);
}
static int hmm_migrate_sys_to_dev(int fd,
struct hmm_buffer *buffer,
unsigned long npages)
{
return hmm_dmirror_cmd(fd, HMM_DMIRROR_MIGRATE_TO_DEV, buffer, npages);
}
static int hmm_migrate_dev_to_sys(int fd,
struct hmm_buffer *buffer,
unsigned long npages)
{
return hmm_dmirror_cmd(fd, HMM_DMIRROR_MIGRATE_TO_SYS, buffer, npages);
}
/*
* Simple NULL test of device open/close.
*/
TEST_F(hmm, open_close)
{
}
/*
* Read private anonymous memory.
*/
TEST_F(hmm, anon_read)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
int val;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/*
* Initialize buffer in system memory but leave the first two pages
* zero (pte_none and pfn_zero).
*/
i = 2 * self->page_size / sizeof(*ptr);
for (ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Set buffer permission to read-only. */
ret = mprotect(buffer->ptr, size, PROT_READ);
ASSERT_EQ(ret, 0);
/* Populate the CPU page table with a special zero page. */
val = *(int *)(buffer->ptr + self->page_size);
ASSERT_EQ(val, 0);
/* Simulate a device reading system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device read. */
ptr = buffer->mirror;
for (i = 0; i < 2 * self->page_size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], 0);
for (; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Read private anonymous memory which has been protected with
* mprotect() PROT_NONE.
*/
TEST_F(hmm, anon_read_prot)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Initialize mirror buffer so we can verify it isn't written. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = -i;
/* Protect buffer from reading. */
ret = mprotect(buffer->ptr, size, PROT_NONE);
ASSERT_EQ(ret, 0);
/* Simulate a device reading system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, npages);
ASSERT_EQ(ret, -EFAULT);
/* Allow CPU to read the buffer so we can check it. */
ret = mprotect(buffer->ptr, size, PROT_READ);
ASSERT_EQ(ret, 0);
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], -i);
hmm_buffer_free(buffer);
}
/*
* Write private anonymous memory.
*/
TEST_F(hmm, anon_write)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize data that the device will write to buffer->ptr. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Write private anonymous memory which has been protected with
* mprotect() PROT_READ.
*/
TEST_F(hmm, anon_write_prot)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Simulate a device reading a zero page of memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, 1);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, 1);
ASSERT_EQ(buffer->faults, 1);
/* Initialize data that the device will write to buffer->ptr. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, -EPERM);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], 0);
/* Now allow writing and see that the zero page is replaced. */
ret = mprotect(buffer->ptr, size, PROT_WRITE | PROT_READ);
ASSERT_EQ(ret, 0);
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Check that a device writing an anonymous private mapping
* will copy-on-write if a child process inherits the mapping.
*/
TEST_F(hmm, anon_write_child)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
pid_t pid;
int child_fd;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer->ptr so we can tell if it is written. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Initialize data that the device will write to buffer->ptr. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = -i;
pid = fork();
if (pid == -1)
ASSERT_EQ(pid, 0);
if (pid != 0) {
waitpid(pid, &ret, 0);
ASSERT_EQ(WIFEXITED(ret), 1);
/* Check that the parent's buffer did not change. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
return;
}
/* Check that we see the parent's values. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], -i);
/* The child process needs its own mirror to its own mm. */
child_fd = hmm_open(0);
ASSERT_GE(child_fd, 0);
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(child_fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], -i);
close(child_fd);
exit(0);
}
/*
* Check that a device writing an anonymous shared mapping
* will not copy-on-write if a child process inherits the mapping.
*/
TEST_F(hmm, anon_write_child_shared)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
pid_t pid;
int child_fd;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer->ptr so we can tell if it is written. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Initialize data that the device will write to buffer->ptr. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = -i;
pid = fork();
if (pid == -1)
ASSERT_EQ(pid, 0);
if (pid != 0) {
waitpid(pid, &ret, 0);
ASSERT_EQ(WIFEXITED(ret), 1);
/* Check that the parent's buffer did change. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], -i);
return;
}
/* Check that we see the parent's values. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], -i);
/* The child process needs its own mirror to its own mm. */
child_fd = hmm_open(0);
ASSERT_GE(child_fd, 0);
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(child_fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], -i);
close(child_fd);
exit(0);
}
/*
* Write private anonymous huge page.
*/
TEST_F(hmm, anon_write_huge)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
void *old_ptr;
void *map;
int *ptr;
int ret;
size = 2 * TWOMEG;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
size = TWOMEG;
npages = size >> self->page_shift;
map = (void *)ALIGN((uintptr_t)buffer->ptr, size);
ret = madvise(map, size, MADV_HUGEPAGE);
ASSERT_EQ(ret, 0);
old_ptr = buffer->ptr;
buffer->ptr = map;
/* Initialize data that the device will write to buffer->ptr. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
buffer->ptr = old_ptr;
hmm_buffer_free(buffer);
}
/*
* Read numeric data from raw and tagged kernel status files. Used to read
* /proc and /sys data (without a tag) and from /proc/meminfo (with a tag).
*/
static long file_read_ulong(char *file, const char *tag)
{
int fd;
char buf[2048];
int len;
char *p, *q;
long val;
fd = open(file, O_RDONLY);
if (fd < 0) {
/* Error opening the file */
return -1;
}
len = read(fd, buf, sizeof(buf));
close(fd);
if (len < 0) {
/* Error in reading the file */
return -1;
}
if (len == sizeof(buf)) {
/* Error file is too large */
return -1;
}
buf[len] = '\0';
/* Search for a tag if provided */
if (tag) {
p = strstr(buf, tag);
if (!p)
return -1; /* looks like the line we want isn't there */
p += strlen(tag);
} else
p = buf;
val = strtol(p, &q, 0);
if (*q != ' ') {
/* Error parsing the file */
return -1;
}
return val;
}
/*
* Write huge TLBFS page.
*/
TEST_F(hmm, anon_write_hugetlbfs)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long default_hsize;
unsigned long i;
int *ptr;
int ret;
default_hsize = file_read_ulong("/proc/meminfo", "Hugepagesize:");
if (default_hsize < 0 || default_hsize*1024 < default_hsize)
SKIP(return, "Huge page size could not be determined");
default_hsize = default_hsize*1024; /* KB to B */
size = ALIGN(TWOMEG, default_hsize);
npages = size >> self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
-1, 0);
if (buffer->ptr == MAP_FAILED) {
free(buffer);
SKIP(return, "Huge page could not be allocated");
}
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
/* Initialize data that the device will write to buffer->ptr. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
munmap(buffer->ptr, buffer->size);
buffer->ptr = NULL;
hmm_buffer_free(buffer);
}
/*
* Read mmap'ed file memory.
*/
TEST_F(hmm, file_read)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
int fd;
ssize_t len;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
fd = hmm_create_file(size);
ASSERT_GE(fd, 0);
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = fd;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
/* Write initial contents of the file. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
len = pwrite(fd, buffer->mirror, size, 0);
ASSERT_EQ(len, size);
memset(buffer->mirror, 0, size);
buffer->ptr = mmap(NULL, size,
PROT_READ,
MAP_SHARED,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Simulate a device reading system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Write mmap'ed file memory.
*/
TEST_F(hmm, file_write)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
int fd;
ssize_t len;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
fd = hmm_create_file(size);
ASSERT_GE(fd, 0);
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = fd;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_SHARED,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize data that the device will write to buffer->ptr. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device wrote. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Check that the device also wrote the file. */
len = pread(fd, buffer->mirror, size, 0);
ASSERT_EQ(len, size);
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Migrate anonymous memory to device private memory.
*/
TEST_F(hmm, migrate)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Migrate memory to device. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Migrate anonymous memory to device private memory and fault some of it back
* to system memory, then try migrating the resulting mix of system and device
* private memory to the device.
*/
TEST_F(hmm, migrate_fault)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Migrate memory to device. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Fault half the pages back to system memory and check them. */
for (i = 0, ptr = buffer->ptr; i < size / (2 * sizeof(*ptr)); ++i)
ASSERT_EQ(ptr[i], i);
/* Migrate memory to the device again. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
TEST_F(hmm, migrate_release)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Migrate memory to device. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Release device memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_RELEASE, buffer, npages);
ASSERT_EQ(ret, 0);
/* Fault pages back to system memory and check them. */
for (i = 0, ptr = buffer->ptr; i < size / (2 * sizeof(*ptr)); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Migrate anonymous shared memory to device private memory.
*/
TEST_F(hmm, migrate_shared)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Migrate memory to device. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, -ENOENT);
hmm_buffer_free(buffer);
}
/*
* Try to migrate various memory types to device private memory.
*/
TEST_F(hmm2, migrate_mixed)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
int *ptr;
unsigned char *p;
int ret;
int val;
npages = 6;
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
/* Reserve a range of addresses. */
buffer->ptr = mmap(NULL, size,
PROT_NONE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
p = buffer->ptr;
/* Migrating a protected area should be an error. */
ret = hmm_migrate_sys_to_dev(self->fd1, buffer, npages);
ASSERT_EQ(ret, -EINVAL);
/* Punch a hole after the first page address. */
ret = munmap(buffer->ptr + self->page_size, self->page_size);
ASSERT_EQ(ret, 0);
/* We expect an error if the vma doesn't cover the range. */
ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 3);
ASSERT_EQ(ret, -EINVAL);
/* Page 2 will be a read-only zero page. */
ret = mprotect(buffer->ptr + 2 * self->page_size, self->page_size,
PROT_READ);
ASSERT_EQ(ret, 0);
ptr = (int *)(buffer->ptr + 2 * self->page_size);
val = *ptr + 3;
ASSERT_EQ(val, 3);
/* Page 3 will be read-only. */
ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
PROT_READ | PROT_WRITE);
ASSERT_EQ(ret, 0);
ptr = (int *)(buffer->ptr + 3 * self->page_size);
*ptr = val;
ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
PROT_READ);
ASSERT_EQ(ret, 0);
/* Page 4-5 will be read-write. */
ret = mprotect(buffer->ptr + 4 * self->page_size, 2 * self->page_size,
PROT_READ | PROT_WRITE);
ASSERT_EQ(ret, 0);
ptr = (int *)(buffer->ptr + 4 * self->page_size);
*ptr = val;
ptr = (int *)(buffer->ptr + 5 * self->page_size);
*ptr = val;
/* Now try to migrate pages 2-5 to device 1. */
buffer->ptr = p + 2 * self->page_size;
ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 4);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, 4);
/* Page 5 won't be migrated to device 0 because it's on device 1. */
buffer->ptr = p + 5 * self->page_size;
ret = hmm_migrate_sys_to_dev(self->fd0, buffer, 1);
ASSERT_EQ(ret, -ENOENT);
buffer->ptr = p;
buffer->ptr = p;
hmm_buffer_free(buffer);
}
/*
* Migrate anonymous memory to device memory and back to system memory
* multiple times. In case of private zone configuration, this is done
* through fault pages accessed by CPU. In case of coherent zone configuration,
* the pages from the device should be explicitly migrated back to system memory.
* The reason is Coherent device zone has coherent access by CPU, therefore
* it will not generate any page fault.
*/
TEST_F(hmm, migrate_multiple)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
unsigned long c;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
for (c = 0; c < NTIMES; c++) {
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Migrate memory to device. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Migrate back to system memory and check them. */
if (hmm_is_coherent_type(variant->device_number)) {
ret = hmm_migrate_dev_to_sys(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
}
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
}
/*
* Read anonymous memory multiple times.
*/
TEST_F(hmm, anon_read_multiple)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
unsigned long c;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
for (c = 0; c < NTIMES; c++) {
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i + c;
/* Simulate a device reading system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer,
npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i + c);
hmm_buffer_free(buffer);
}
}
void *unmap_buffer(void *p)
{
struct hmm_buffer *buffer = p;
/* Delay for a bit and then unmap buffer while it is being read. */
hmm_nanosleep(hmm_random() % 32000);
munmap(buffer->ptr + buffer->size / 2, buffer->size / 2);
buffer->ptr = NULL;
return NULL;
}
/*
* Try reading anonymous memory while it is being unmapped.
*/
TEST_F(hmm, anon_teardown)
{
unsigned long npages;
unsigned long size;
unsigned long c;
void *ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
for (c = 0; c < NTIMES; ++c) {
pthread_t thread;
struct hmm_buffer *buffer;
unsigned long i;
int *ptr;
int rc;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i + c;
rc = pthread_create(&thread, NULL, unmap_buffer, buffer);
ASSERT_EQ(rc, 0);
/* Simulate a device reading system memory. */
rc = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer,
npages);
if (rc == 0) {
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror;
i < size / sizeof(*ptr);
++i)
ASSERT_EQ(ptr[i], i + c);
}
pthread_join(thread, &ret);
hmm_buffer_free(buffer);
}
}
/*
* Test memory snapshot without faulting in pages accessed by the device.
*/
TEST_F(hmm, mixedmap)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned char *m;
int ret;
npages = 1;
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(npages);
ASSERT_NE(buffer->mirror, NULL);
/* Reserve a range of addresses. */
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE,
self->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Simulate a device snapshotting CPU pagetables. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device saw. */
m = buffer->mirror;
ASSERT_EQ(m[0], HMM_DMIRROR_PROT_READ);
hmm_buffer_free(buffer);
}
/*
* Test memory snapshot without faulting in pages accessed by the device.
*/
TEST_F(hmm2, snapshot)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
int *ptr;
unsigned char *p;
unsigned char *m;
int ret;
int val;
npages = 7;
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(npages);
ASSERT_NE(buffer->mirror, NULL);
/* Reserve a range of addresses. */
buffer->ptr = mmap(NULL, size,
PROT_NONE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
p = buffer->ptr;
/* Punch a hole after the first page address. */
ret = munmap(buffer->ptr + self->page_size, self->page_size);
ASSERT_EQ(ret, 0);
/* Page 2 will be read-only zero page. */
ret = mprotect(buffer->ptr + 2 * self->page_size, self->page_size,
PROT_READ);
ASSERT_EQ(ret, 0);
ptr = (int *)(buffer->ptr + 2 * self->page_size);
val = *ptr + 3;
ASSERT_EQ(val, 3);
/* Page 3 will be read-only. */
ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
PROT_READ | PROT_WRITE);
ASSERT_EQ(ret, 0);
ptr = (int *)(buffer->ptr + 3 * self->page_size);
*ptr = val;
ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
PROT_READ);
ASSERT_EQ(ret, 0);
/* Page 4-6 will be read-write. */
ret = mprotect(buffer->ptr + 4 * self->page_size, 3 * self->page_size,
PROT_READ | PROT_WRITE);
ASSERT_EQ(ret, 0);
ptr = (int *)(buffer->ptr + 4 * self->page_size);
*ptr = val;
/* Page 5 will be migrated to device 0. */
buffer->ptr = p + 5 * self->page_size;
ret = hmm_migrate_sys_to_dev(self->fd0, buffer, 1);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, 1);
/* Page 6 will be migrated to device 1. */
buffer->ptr = p + 6 * self->page_size;
ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 1);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, 1);
/* Simulate a device snapshotting CPU pagetables. */
buffer->ptr = p;
ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_SNAPSHOT, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device saw. */
m = buffer->mirror;
ASSERT_EQ(m[0], HMM_DMIRROR_PROT_ERROR);
ASSERT_EQ(m[1], HMM_DMIRROR_PROT_ERROR);
ASSERT_EQ(m[2], HMM_DMIRROR_PROT_ZERO | HMM_DMIRROR_PROT_READ);
ASSERT_EQ(m[3], HMM_DMIRROR_PROT_READ);
ASSERT_EQ(m[4], HMM_DMIRROR_PROT_WRITE);
if (!hmm_is_coherent_type(variant->device_number0)) {
ASSERT_EQ(m[5], HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL |
HMM_DMIRROR_PROT_WRITE);
ASSERT_EQ(m[6], HMM_DMIRROR_PROT_NONE);
} else {
ASSERT_EQ(m[5], HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL |
HMM_DMIRROR_PROT_WRITE);
ASSERT_EQ(m[6], HMM_DMIRROR_PROT_DEV_COHERENT_REMOTE |
HMM_DMIRROR_PROT_WRITE);
}
hmm_buffer_free(buffer);
}
/*
* Test the hmm_range_fault() HMM_PFN_PMD flag for large pages that
* should be mapped by a large page table entry.
*/
TEST_F(hmm, compound)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long default_hsize;
int *ptr;
unsigned char *m;
int ret;
unsigned long i;
/* Skip test if we can't allocate a hugetlbfs page. */
default_hsize = file_read_ulong("/proc/meminfo", "Hugepagesize:");
if (default_hsize < 0 || default_hsize*1024 < default_hsize)
SKIP(return, "Huge page size could not be determined");
default_hsize = default_hsize*1024; /* KB to B */
size = ALIGN(TWOMEG, default_hsize);
npages = size >> self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
-1, 0);
if (buffer->ptr == MAP_FAILED) {
free(buffer);
return;
}
buffer->size = size;
buffer->mirror = malloc(npages);
ASSERT_NE(buffer->mirror, NULL);
/* Initialize the pages the device will snapshot in buffer->ptr. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Simulate a device snapshotting CPU pagetables. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device saw. */
m = buffer->mirror;
for (i = 0; i < npages; ++i)
ASSERT_EQ(m[i], HMM_DMIRROR_PROT_WRITE |
HMM_DMIRROR_PROT_PMD);
/* Make the region read-only. */
ret = mprotect(buffer->ptr, size, PROT_READ);
ASSERT_EQ(ret, 0);
/* Simulate a device snapshotting CPU pagetables. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device saw. */
m = buffer->mirror;
for (i = 0; i < npages; ++i)
ASSERT_EQ(m[i], HMM_DMIRROR_PROT_READ |
HMM_DMIRROR_PROT_PMD);
munmap(buffer->ptr, buffer->size);
buffer->ptr = NULL;
hmm_buffer_free(buffer);
}
/*
* Test two devices reading the same memory (double mapped).
*/
TEST_F(hmm2, double_map)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = 6;
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(npages);
ASSERT_NE(buffer->mirror, NULL);
/* Reserve a range of addresses. */
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Make region read-only. */
ret = mprotect(buffer->ptr, size, PROT_READ);
ASSERT_EQ(ret, 0);
/* Simulate device 0 reading system memory. */
ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_READ, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Simulate device 1 reading system memory. */
ret = hmm_dmirror_cmd(self->fd1, HMM_DMIRROR_READ, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Migrate pages to device 1 and try to read from device 0. */
ret = hmm_migrate_sys_to_dev(self->fd1, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_READ, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
ASSERT_EQ(buffer->faults, 1);
/* Check what device 0 read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
hmm_buffer_free(buffer);
}
/*
* Basic check of exclusive faulting.
*/
TEST_F(hmm, exclusive)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Map memory exclusively for device access. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_EXCLUSIVE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
/* Fault pages back to system memory and check them. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i]++, i);
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i+1);
/* Check atomic access revoked */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_CHECK_EXCLUSIVE, buffer, npages);
ASSERT_EQ(ret, 0);
hmm_buffer_free(buffer);
}
TEST_F(hmm, exclusive_mprotect)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Map memory exclusively for device access. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_EXCLUSIVE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
ret = mprotect(buffer->ptr, size, PROT_READ);
ASSERT_EQ(ret, 0);
/* Simulate a device writing system memory. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
ASSERT_EQ(ret, -EPERM);
hmm_buffer_free(buffer);
}
/*
* Check copy-on-write works.
*/
TEST_F(hmm, exclusive_cow)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
ASSERT_NE(npages, 0);
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Map memory exclusively for device access. */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_EXCLUSIVE, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
fork();
/* Fault pages back to system memory and check them. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i]++, i);
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i+1);
hmm_buffer_free(buffer);
}
static int gup_test_exec(int gup_fd, unsigned long addr, int cmd,
int npages, int size, int flags)
{
struct gup_test gup = {
.nr_pages_per_call = npages,
.addr = addr,
.gup_flags = FOLL_WRITE | flags,
.size = size,
};
if (ioctl(gup_fd, cmd, &gup)) {
perror("ioctl on error\n");
return errno;
}
return 0;
}
/*
* Test get user device pages through gup_test. Setting PIN_LONGTERM flag.
* This should trigger a migration back to system memory for both, private
* and coherent type pages.
* This test makes use of gup_test module. Make sure GUP_TEST_CONFIG is added
* to your configuration before you run it.
*/
TEST_F(hmm, hmm_gup_test)
{
struct hmm_buffer *buffer;
int gup_fd;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
unsigned char *m;
gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR);
if (gup_fd == -1)
SKIP(return, "Skipping test, could not find gup_test driver");
npages = 4;
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Migrate memory to device. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
/* Check what the device read. */
for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
ASSERT_EQ(gup_test_exec(gup_fd,
(unsigned long)buffer->ptr,
GUP_BASIC_TEST, 1, self->page_size, 0), 0);
ASSERT_EQ(gup_test_exec(gup_fd,
(unsigned long)buffer->ptr + 1 * self->page_size,
GUP_FAST_BENCHMARK, 1, self->page_size, 0), 0);
ASSERT_EQ(gup_test_exec(gup_fd,
(unsigned long)buffer->ptr + 2 * self->page_size,
PIN_FAST_BENCHMARK, 1, self->page_size, FOLL_LONGTERM), 0);
ASSERT_EQ(gup_test_exec(gup_fd,
(unsigned long)buffer->ptr + 3 * self->page_size,
PIN_LONGTERM_BENCHMARK, 1, self->page_size, 0), 0);
/* Take snapshot to CPU pagetables */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
m = buffer->mirror;
if (hmm_is_coherent_type(variant->device_number)) {
ASSERT_EQ(HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL | HMM_DMIRROR_PROT_WRITE, m[0]);
ASSERT_EQ(HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL | HMM_DMIRROR_PROT_WRITE, m[1]);
} else {
ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[0]);
ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[1]);
}
ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[2]);
ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[3]);
/*
* Check again the content on the pages. Make sure there's no
* corrupted data.
*/
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ASSERT_EQ(ptr[i], i);
close(gup_fd);
hmm_buffer_free(buffer);
}
/*
* Test copy-on-write in device pages.
* In case of writing to COW private page(s), a page fault will migrate pages
* back to system memory first. Then, these pages will be duplicated. In case
* of COW device coherent type, pages are duplicated directly from device
* memory.
*/
TEST_F(hmm, hmm_cow_in_device)
{
struct hmm_buffer *buffer;
unsigned long npages;
unsigned long size;
unsigned long i;
int *ptr;
int ret;
unsigned char *m;
pid_t pid;
int status;
npages = 4;
size = npages << self->page_shift;
buffer = malloc(sizeof(*buffer));
ASSERT_NE(buffer, NULL);
buffer->fd = -1;
buffer->size = size;
buffer->mirror = malloc(size);
ASSERT_NE(buffer->mirror, NULL);
buffer->ptr = mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
buffer->fd, 0);
ASSERT_NE(buffer->ptr, MAP_FAILED);
/* Initialize buffer in system memory. */
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Migrate memory to device. */
ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
pid = fork();
if (pid == -1)
ASSERT_EQ(pid, 0);
if (!pid) {
/* Child process waitd for SIGTERM from the parent. */
while (1) {
}
perror("Should not reach this\n");
exit(0);
}
/* Parent process writes to COW pages(s) and gets a
* new copy in system. In case of device private pages,
* this write causes a migration to system mem first.
*/
for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
ptr[i] = i;
/* Terminate child and wait */
EXPECT_EQ(0, kill(pid, SIGTERM));
EXPECT_EQ(pid, waitpid(pid, &status, 0));
EXPECT_NE(0, WIFSIGNALED(status));
EXPECT_EQ(SIGTERM, WTERMSIG(status));
/* Take snapshot to CPU pagetables */
ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
ASSERT_EQ(ret, 0);
ASSERT_EQ(buffer->cpages, npages);
m = buffer->mirror;
for (i = 0; i < npages; i++)
ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[i]);
hmm_buffer_free(buffer);
}
TEST_HARNESS_MAIN
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