hmm-tests: add test for migrate_device_range()

Link: https://lkml.kernel.org/r/a73cf109de0224cfd118d22be58ddebac3ae2897.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Alistair Popple 2022-09-28 22:01:22 +10:00 committed by Andrew Morton
parent 249881232e
commit ad4c365221
3 changed files with 149 additions and 21 deletions

View File

@ -100,6 +100,7 @@ struct dmirror {
struct dmirror_chunk {
struct dev_pagemap pagemap;
struct dmirror_device *mdevice;
bool remove;
};
/*
@ -192,11 +193,15 @@ static int dmirror_fops_release(struct inode *inode, struct file *filp)
return 0;
}
static struct dmirror_chunk *dmirror_page_to_chunk(struct page *page)
{
return container_of(page->pgmap, struct dmirror_chunk, pagemap);
}
static struct dmirror_device *dmirror_page_to_device(struct page *page)
{
return container_of(page->pgmap, struct dmirror_chunk,
pagemap)->mdevice;
return dmirror_page_to_chunk(page)->mdevice;
}
static int dmirror_do_fault(struct dmirror *dmirror, struct hmm_range *range)
@ -1218,6 +1223,85 @@ static int dmirror_snapshot(struct dmirror *dmirror,
return ret;
}
static void dmirror_device_evict_chunk(struct dmirror_chunk *chunk)
{
unsigned long start_pfn = chunk->pagemap.range.start >> PAGE_SHIFT;
unsigned long end_pfn = chunk->pagemap.range.end >> PAGE_SHIFT;
unsigned long npages = end_pfn - start_pfn + 1;
unsigned long i;
unsigned long *src_pfns;
unsigned long *dst_pfns;
src_pfns = kcalloc(npages, sizeof(*src_pfns), GFP_KERNEL);
dst_pfns = kcalloc(npages, sizeof(*dst_pfns), GFP_KERNEL);
migrate_device_range(src_pfns, start_pfn, npages);
for (i = 0; i < npages; i++) {
struct page *dpage, *spage;
spage = migrate_pfn_to_page(src_pfns[i]);
if (!spage || !(src_pfns[i] & MIGRATE_PFN_MIGRATE))
continue;
if (WARN_ON(!is_device_private_page(spage) &&
!is_device_coherent_page(spage)))
continue;
spage = BACKING_PAGE(spage);
dpage = alloc_page(GFP_HIGHUSER_MOVABLE | __GFP_NOFAIL);
lock_page(dpage);
copy_highpage(dpage, spage);
dst_pfns[i] = migrate_pfn(page_to_pfn(dpage));
if (src_pfns[i] & MIGRATE_PFN_WRITE)
dst_pfns[i] |= MIGRATE_PFN_WRITE;
}
migrate_device_pages(src_pfns, dst_pfns, npages);
migrate_device_finalize(src_pfns, dst_pfns, npages);
kfree(src_pfns);
kfree(dst_pfns);
}
/* Removes free pages from the free list so they can't be re-allocated */
static void dmirror_remove_free_pages(struct dmirror_chunk *devmem)
{
struct dmirror_device *mdevice = devmem->mdevice;
struct page *page;
for (page = mdevice->free_pages; page; page = page->zone_device_data)
if (dmirror_page_to_chunk(page) == devmem)
mdevice->free_pages = page->zone_device_data;
}
static void dmirror_device_remove_chunks(struct dmirror_device *mdevice)
{
unsigned int i;
mutex_lock(&mdevice->devmem_lock);
if (mdevice->devmem_chunks) {
for (i = 0; i < mdevice->devmem_count; i++) {
struct dmirror_chunk *devmem =
mdevice->devmem_chunks[i];
spin_lock(&mdevice->lock);
devmem->remove = true;
dmirror_remove_free_pages(devmem);
spin_unlock(&mdevice->lock);
dmirror_device_evict_chunk(devmem);
memunmap_pages(&devmem->pagemap);
if (devmem->pagemap.type == MEMORY_DEVICE_PRIVATE)
release_mem_region(devmem->pagemap.range.start,
range_len(&devmem->pagemap.range));
kfree(devmem);
}
mdevice->devmem_count = 0;
mdevice->devmem_capacity = 0;
mdevice->free_pages = NULL;
kfree(mdevice->devmem_chunks);
mdevice->devmem_chunks = NULL;
}
mutex_unlock(&mdevice->devmem_lock);
}
static long dmirror_fops_unlocked_ioctl(struct file *filp,
unsigned int command,
unsigned long arg)
@ -1272,6 +1356,11 @@ static long dmirror_fops_unlocked_ioctl(struct file *filp,
ret = dmirror_snapshot(dmirror, &cmd);
break;
case HMM_DMIRROR_RELEASE:
dmirror_device_remove_chunks(dmirror->mdevice);
ret = 0;
break;
default:
return -EINVAL;
}
@ -1326,9 +1415,13 @@ static void dmirror_devmem_free(struct page *page)
mdevice = dmirror_page_to_device(page);
spin_lock(&mdevice->lock);
/* Return page to our allocator if not freeing the chunk */
if (!dmirror_page_to_chunk(page)->remove) {
mdevice->cfree++;
page->zone_device_data = mdevice->free_pages;
mdevice->free_pages = page;
}
spin_unlock(&mdevice->lock);
}
@ -1408,22 +1501,7 @@ static int dmirror_device_init(struct dmirror_device *mdevice, int id)
static void dmirror_device_remove(struct dmirror_device *mdevice)
{
unsigned int i;
if (mdevice->devmem_chunks) {
for (i = 0; i < mdevice->devmem_count; i++) {
struct dmirror_chunk *devmem =
mdevice->devmem_chunks[i];
memunmap_pages(&devmem->pagemap);
if (devmem->pagemap.type == MEMORY_DEVICE_PRIVATE)
release_mem_region(devmem->pagemap.range.start,
range_len(&devmem->pagemap.range));
kfree(devmem);
}
kfree(mdevice->devmem_chunks);
}
dmirror_device_remove_chunks(mdevice);
cdev_device_del(&mdevice->cdevice, &mdevice->device);
}

View File

@ -36,6 +36,7 @@ struct hmm_dmirror_cmd {
#define HMM_DMIRROR_SNAPSHOT _IOWR('H', 0x04, struct hmm_dmirror_cmd)
#define HMM_DMIRROR_EXCLUSIVE _IOWR('H', 0x05, struct hmm_dmirror_cmd)
#define HMM_DMIRROR_CHECK_EXCLUSIVE _IOWR('H', 0x06, struct hmm_dmirror_cmd)
#define HMM_DMIRROR_RELEASE _IOWR('H', 0x07, struct hmm_dmirror_cmd)
/*
* Values returned in hmm_dmirror_cmd.ptr for HMM_DMIRROR_SNAPSHOT.

View File

@ -1054,6 +1054,55 @@ TEST_F(hmm, migrate_fault)
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.
*/