linux/drivers/misc/habanalabs/memory.c

1722 lines
44 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2016-2019 HabanaLabs, Ltd.
* All Rights Reserved.
*/
#include <uapi/misc/habanalabs.h>
#include "habanalabs.h"
#include "include/hw_ip/mmu/mmu_general.h"
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/genalloc.h>
#define PGS_IN_2MB_PAGE (PAGE_SIZE_2MB >> PAGE_SHIFT)
#define HL_MMU_DEBUG 0
/*
* The va ranges in context object contain a list with the available chunks of
* device virtual memory.
* There is one range for host allocations and one for DRAM allocations.
*
* On initialization each range contains one chunk of all of its available
* virtual range which is a half of the total device virtual range.
*
* On each mapping of physical pages, a suitable virtual range chunk (with a
* minimum size) is selected from the list. If the chunk size equals the
* requested size, the chunk is returned. Otherwise, the chunk is split into
* two chunks - one to return as result and a remainder to stay in the list.
*
* On each Unmapping of a virtual address, the relevant virtual chunk is
* returned to the list. The chunk is added to the list and if its edges match
* the edges of the adjacent chunks (means a contiguous chunk can be created),
* the chunks are merged.
*
* On finish, the list is checked to have only one chunk of all the relevant
* virtual range (which is a half of the device total virtual range).
* If not (means not all mappings were unmapped), a warning is printed.
*/
/*
* alloc_device_memory - allocate device memory
*
* @ctx : current context
* @args : host parameters containing the requested size
* @ret_handle : result handle
*
* This function does the following:
* - Allocate the requested size rounded up to 2MB pages
* - Return unique handle
*/
static int alloc_device_memory(struct hl_ctx *ctx, struct hl_mem_in *args,
u32 *ret_handle)
{
struct hl_device *hdev = ctx->hdev;
struct hl_vm *vm = &hdev->vm;
struct hl_vm_phys_pg_pack *phys_pg_pack;
u64 paddr = 0, total_size, num_pgs, i;
u32 num_curr_pgs, page_size, page_shift;
int handle, rc;
bool contiguous;
num_curr_pgs = 0;
page_size = hdev->asic_prop.dram_page_size;
page_shift = __ffs(page_size);
num_pgs = (args->alloc.mem_size + (page_size - 1)) >> page_shift;
total_size = num_pgs << page_shift;
contiguous = args->flags & HL_MEM_CONTIGUOUS;
if (contiguous) {
paddr = (u64) gen_pool_alloc(vm->dram_pg_pool, total_size);
if (!paddr) {
dev_err(hdev->dev,
"failed to allocate %llu huge contiguous pages\n",
num_pgs);
return -ENOMEM;
}
}
phys_pg_pack = kzalloc(sizeof(*phys_pg_pack), GFP_KERNEL);
if (!phys_pg_pack) {
rc = -ENOMEM;
goto pages_pack_err;
}
phys_pg_pack->vm_type = VM_TYPE_PHYS_PACK;
phys_pg_pack->asid = ctx->asid;
phys_pg_pack->npages = num_pgs;
phys_pg_pack->page_size = page_size;
phys_pg_pack->total_size = total_size;
phys_pg_pack->flags = args->flags;
phys_pg_pack->contiguous = contiguous;
phys_pg_pack->pages = kvmalloc_array(num_pgs, sizeof(u64), GFP_KERNEL);
if (!phys_pg_pack->pages) {
rc = -ENOMEM;
goto pages_arr_err;
}
if (phys_pg_pack->contiguous) {
for (i = 0 ; i < num_pgs ; i++)
phys_pg_pack->pages[i] = paddr + i * page_size;
} else {
for (i = 0 ; i < num_pgs ; i++) {
phys_pg_pack->pages[i] = (u64) gen_pool_alloc(
vm->dram_pg_pool,
page_size);
if (!phys_pg_pack->pages[i]) {
dev_err(hdev->dev,
"Failed to allocate device memory (out of memory)\n");
rc = -ENOMEM;
goto page_err;
}
num_curr_pgs++;
}
}
spin_lock(&vm->idr_lock);
handle = idr_alloc(&vm->phys_pg_pack_handles, phys_pg_pack, 1, 0,
GFP_ATOMIC);
spin_unlock(&vm->idr_lock);
if (handle < 0) {
dev_err(hdev->dev, "Failed to get handle for page\n");
rc = -EFAULT;
goto idr_err;
}
for (i = 0 ; i < num_pgs ; i++)
kref_get(&vm->dram_pg_pool_refcount);
phys_pg_pack->handle = handle;
atomic64_add(phys_pg_pack->total_size, &ctx->dram_phys_mem);
atomic64_add(phys_pg_pack->total_size, &hdev->dram_used_mem);
*ret_handle = handle;
return 0;
idr_err:
page_err:
if (!phys_pg_pack->contiguous)
for (i = 0 ; i < num_curr_pgs ; i++)
gen_pool_free(vm->dram_pg_pool, phys_pg_pack->pages[i],
page_size);
kvfree(phys_pg_pack->pages);
pages_arr_err:
kfree(phys_pg_pack);
pages_pack_err:
if (contiguous)
gen_pool_free(vm->dram_pg_pool, paddr, total_size);
return rc;
}
/*
* get_userptr_from_host_va - initialize userptr structure from given host
* virtual address
*
* @hdev : habanalabs device structure
* @args : parameters containing the virtual address and size
* @p_userptr : pointer to result userptr structure
*
* This function does the following:
* - Allocate userptr structure
* - Pin the given host memory using the userptr structure
* - Perform DMA mapping to have the DMA addresses of the pages
*/
static int get_userptr_from_host_va(struct hl_device *hdev,
struct hl_mem_in *args, struct hl_userptr **p_userptr)
{
struct hl_userptr *userptr;
int rc;
userptr = kzalloc(sizeof(*userptr), GFP_KERNEL);
if (!userptr) {
rc = -ENOMEM;
goto userptr_err;
}
rc = hl_pin_host_memory(hdev, args->map_host.host_virt_addr,
args->map_host.mem_size, userptr);
if (rc) {
dev_err(hdev->dev, "Failed to pin host memory\n");
goto pin_err;
}
rc = hdev->asic_funcs->asic_dma_map_sg(hdev, userptr->sgt->sgl,
userptr->sgt->nents, DMA_BIDIRECTIONAL);
if (rc) {
dev_err(hdev->dev, "failed to map sgt with DMA region\n");
goto dma_map_err;
}
userptr->dma_mapped = true;
userptr->dir = DMA_BIDIRECTIONAL;
userptr->vm_type = VM_TYPE_USERPTR;
*p_userptr = userptr;
return 0;
dma_map_err:
hl_unpin_host_memory(hdev, userptr);
pin_err:
kfree(userptr);
userptr_err:
return rc;
}
/*
* free_userptr - free userptr structure
*
* @hdev : habanalabs device structure
* @userptr : userptr to free
*
* This function does the following:
* - Unpins the physical pages
* - Frees the userptr structure
*/
static void free_userptr(struct hl_device *hdev, struct hl_userptr *userptr)
{
hl_unpin_host_memory(hdev, userptr);
kfree(userptr);
}
/*
* dram_pg_pool_do_release - free DRAM pages pool
*
* @ref : pointer to reference object
*
* This function does the following:
* - Frees the idr structure of physical pages handles
* - Frees the generic pool of DRAM physical pages
*/
static void dram_pg_pool_do_release(struct kref *ref)
{
struct hl_vm *vm = container_of(ref, struct hl_vm,
dram_pg_pool_refcount);
/*
* free the idr here as only here we know for sure that there are no
* allocated physical pages and hence there are no handles in use
*/
idr_destroy(&vm->phys_pg_pack_handles);
gen_pool_destroy(vm->dram_pg_pool);
}
/*
* free_phys_pg_pack - free physical page pack
*
* @hdev : habanalabs device structure
* @phys_pg_pack : physical page pack to free
*
* This function does the following:
* - For DRAM memory only, iterate over the pack and free each physical block
* structure by returning it to the general pool
* - Free the hl_vm_phys_pg_pack structure
*/
static void free_phys_pg_pack(struct hl_device *hdev,
struct hl_vm_phys_pg_pack *phys_pg_pack)
{
struct hl_vm *vm = &hdev->vm;
u64 i;
if (!phys_pg_pack->created_from_userptr) {
if (phys_pg_pack->contiguous) {
gen_pool_free(vm->dram_pg_pool, phys_pg_pack->pages[0],
phys_pg_pack->total_size);
for (i = 0; i < phys_pg_pack->npages ; i++)
kref_put(&vm->dram_pg_pool_refcount,
dram_pg_pool_do_release);
} else {
for (i = 0 ; i < phys_pg_pack->npages ; i++) {
gen_pool_free(vm->dram_pg_pool,
phys_pg_pack->pages[i],
phys_pg_pack->page_size);
kref_put(&vm->dram_pg_pool_refcount,
dram_pg_pool_do_release);
}
}
}
kvfree(phys_pg_pack->pages);
kfree(phys_pg_pack);
}
/*
* free_device_memory - free device memory
*
* @ctx : current context
* @handle : handle of the memory chunk to free
*
* This function does the following:
* - Free the device memory related to the given handle
*/
static int free_device_memory(struct hl_ctx *ctx, u32 handle)
{
struct hl_device *hdev = ctx->hdev;
struct hl_vm *vm = &hdev->vm;
struct hl_vm_phys_pg_pack *phys_pg_pack;
spin_lock(&vm->idr_lock);
phys_pg_pack = idr_find(&vm->phys_pg_pack_handles, handle);
if (phys_pg_pack) {
if (atomic_read(&phys_pg_pack->mapping_cnt) > 0) {
dev_err(hdev->dev, "handle %u is mapped, cannot free\n",
handle);
spin_unlock(&vm->idr_lock);
return -EINVAL;
}
/*
* must remove from idr before the freeing of the physical
* pages as the refcount of the pool is also the trigger of the
* idr destroy
*/
idr_remove(&vm->phys_pg_pack_handles, handle);
spin_unlock(&vm->idr_lock);
atomic64_sub(phys_pg_pack->total_size, &ctx->dram_phys_mem);
atomic64_sub(phys_pg_pack->total_size, &hdev->dram_used_mem);
free_phys_pg_pack(hdev, phys_pg_pack);
} else {
spin_unlock(&vm->idr_lock);
dev_err(hdev->dev,
"free device memory failed, no match for handle %u\n",
handle);
return -EINVAL;
}
return 0;
}
/*
* clear_va_list_locked - free virtual addresses list
*
* @hdev : habanalabs device structure
* @va_list : list of virtual addresses to free
*
* This function does the following:
* - Iterate over the list and free each virtual addresses block
*
* This function should be called only when va_list lock is taken
*/
static void clear_va_list_locked(struct hl_device *hdev,
struct list_head *va_list)
{
struct hl_vm_va_block *va_block, *tmp;
list_for_each_entry_safe(va_block, tmp, va_list, node) {
list_del(&va_block->node);
kfree(va_block);
}
}
/*
* print_va_list_locked - print virtual addresses list
*
* @hdev : habanalabs device structure
* @va_list : list of virtual addresses to print
*
* This function does the following:
* - Iterate over the list and print each virtual addresses block
*
* This function should be called only when va_list lock is taken
*/
static void print_va_list_locked(struct hl_device *hdev,
struct list_head *va_list)
{
#if HL_MMU_DEBUG
struct hl_vm_va_block *va_block;
dev_dbg(hdev->dev, "print va list:\n");
list_for_each_entry(va_block, va_list, node)
dev_dbg(hdev->dev,
"va block, start: 0x%llx, end: 0x%llx, size: %llu\n",
va_block->start, va_block->end, va_block->size);
#endif
}
/*
* merge_va_blocks_locked - merge a virtual block if possible
*
* @hdev : pointer to the habanalabs device structure
* @va_list : pointer to the virtual addresses block list
* @va_block : virtual block to merge with adjacent blocks
*
* This function does the following:
* - Merge the given blocks with the adjacent blocks if their virtual ranges
* create a contiguous virtual range
*
* This Function should be called only when va_list lock is taken
*/
static void merge_va_blocks_locked(struct hl_device *hdev,
struct list_head *va_list, struct hl_vm_va_block *va_block)
{
struct hl_vm_va_block *prev, *next;
prev = list_prev_entry(va_block, node);
if (&prev->node != va_list && prev->end + 1 == va_block->start) {
prev->end = va_block->end;
prev->size = prev->end - prev->start;
list_del(&va_block->node);
kfree(va_block);
va_block = prev;
}
next = list_next_entry(va_block, node);
if (&next->node != va_list && va_block->end + 1 == next->start) {
next->start = va_block->start;
next->size = next->end - next->start;
list_del(&va_block->node);
kfree(va_block);
}
}
/*
* add_va_block_locked - add a virtual block to the virtual addresses list
*
* @hdev : pointer to the habanalabs device structure
* @va_list : pointer to the virtual addresses block list
* @start : start virtual address
* @end : end virtual address
*
* This function does the following:
* - Add the given block to the virtual blocks list and merge with other
* blocks if a contiguous virtual block can be created
*
* This Function should be called only when va_list lock is taken
*/
static int add_va_block_locked(struct hl_device *hdev,
struct list_head *va_list, u64 start, u64 end)
{
struct hl_vm_va_block *va_block, *res = NULL;
u64 size = end - start;
print_va_list_locked(hdev, va_list);
list_for_each_entry(va_block, va_list, node) {
/* TODO: remove upon matureness */
if (hl_mem_area_crosses_range(start, size, va_block->start,
va_block->end)) {
dev_err(hdev->dev,
"block crossing ranges at start 0x%llx, end 0x%llx\n",
va_block->start, va_block->end);
return -EINVAL;
}
if (va_block->end < start)
res = va_block;
}
va_block = kmalloc(sizeof(*va_block), GFP_KERNEL);
if (!va_block)
return -ENOMEM;
va_block->start = start;
va_block->end = end;
va_block->size = size;
if (!res)
list_add(&va_block->node, va_list);
else
list_add(&va_block->node, &res->node);
merge_va_blocks_locked(hdev, va_list, va_block);
print_va_list_locked(hdev, va_list);
return 0;
}
/*
* add_va_block - wrapper for add_va_block_locked
*
* @hdev : pointer to the habanalabs device structure
* @va_list : pointer to the virtual addresses block list
* @start : start virtual address
* @end : end virtual address
*
* This function does the following:
* - Takes the list lock and calls add_va_block_locked
*/
static inline int add_va_block(struct hl_device *hdev,
struct hl_va_range *va_range, u64 start, u64 end)
{
int rc;
mutex_lock(&va_range->lock);
rc = add_va_block_locked(hdev, &va_range->list, start, end);
mutex_unlock(&va_range->lock);
return rc;
}
/*
* get_va_block - get a virtual block with the requested size
*
* @hdev : pointer to the habanalabs device structure
* @va_range : pointer to the virtual addresses range
* @size : requested block size
* @hint_addr : hint for request address by the user
* @is_userptr : is host or DRAM memory
*
* This function does the following:
* - Iterate on the virtual block list to find a suitable virtual block for the
* requested size
* - Reserve the requested block and update the list
* - Return the start address of the virtual block
*/
static u64 get_va_block(struct hl_device *hdev,
struct hl_va_range *va_range, u64 size, u64 hint_addr,
bool is_userptr)
{
struct hl_vm_va_block *va_block, *new_va_block = NULL;
u64 valid_start, valid_size, prev_start, prev_end, page_mask,
res_valid_start = 0, res_valid_size = 0;
u32 page_size;
bool add_prev = false;
if (is_userptr) {
/*
* We cannot know if the user allocated memory with huge pages
* or not, hence we continue with the biggest possible
* granularity.
*/
page_size = PAGE_SIZE_2MB;
page_mask = PAGE_MASK_2MB;
} else {
page_size = hdev->asic_prop.dram_page_size;
page_mask = ~((u64)page_size - 1);
}
mutex_lock(&va_range->lock);
print_va_list_locked(hdev, &va_range->list);
list_for_each_entry(va_block, &va_range->list, node) {
/* calc the first possible aligned addr */
valid_start = va_block->start;
if (valid_start & (page_size - 1)) {
valid_start &= page_mask;
valid_start += page_size;
if (valid_start > va_block->end)
continue;
}
valid_size = va_block->end - valid_start;
if (valid_size >= size &&
(!new_va_block || valid_size < res_valid_size)) {
new_va_block = va_block;
res_valid_start = valid_start;
res_valid_size = valid_size;
}
if (hint_addr && hint_addr >= valid_start &&
((hint_addr + size) <= va_block->end)) {
new_va_block = va_block;
res_valid_start = hint_addr;
res_valid_size = valid_size;
break;
}
}
if (!new_va_block) {
dev_err(hdev->dev, "no available va block for size %llu\n",
size);
goto out;
}
if (res_valid_start > new_va_block->start) {
prev_start = new_va_block->start;
prev_end = res_valid_start - 1;
new_va_block->start = res_valid_start;
new_va_block->size = res_valid_size;
add_prev = true;
}
if (new_va_block->size > size) {
new_va_block->start += size;
new_va_block->size = new_va_block->end - new_va_block->start;
} else {
list_del(&new_va_block->node);
kfree(new_va_block);
}
if (add_prev)
add_va_block_locked(hdev, &va_range->list, prev_start,
prev_end);
print_va_list_locked(hdev, &va_range->list);
out:
mutex_unlock(&va_range->lock);
return res_valid_start;
}
/*
* get_sg_info - get number of pages and the DMA address from SG list
*
* @sg : the SG list
* @dma_addr : pointer to DMA address to return
*
* Calculate the number of consecutive pages described by the SG list. Take the
* offset of the address in the first page, add to it the length and round it up
* to the number of needed pages.
*/
static u32 get_sg_info(struct scatterlist *sg, dma_addr_t *dma_addr)
{
*dma_addr = sg_dma_address(sg);
return ((((*dma_addr) & (PAGE_SIZE - 1)) + sg_dma_len(sg)) +
(PAGE_SIZE - 1)) >> PAGE_SHIFT;
}
/*
* init_phys_pg_pack_from_userptr - initialize physical page pack from host
* memory
*
* @ctx : current context
* @userptr : userptr to initialize from
* @pphys_pg_pack : res pointer
*
* This function does the following:
* - Pin the physical pages related to the given virtual block
* - Create a physical page pack from the physical pages related to the given
* virtual block
*/
static int init_phys_pg_pack_from_userptr(struct hl_ctx *ctx,
struct hl_userptr *userptr,
struct hl_vm_phys_pg_pack **pphys_pg_pack)
{
struct hl_vm_phys_pg_pack *phys_pg_pack;
struct scatterlist *sg;
dma_addr_t dma_addr;
u64 page_mask, total_npages;
u32 npages, page_size = PAGE_SIZE;
bool first = true, is_huge_page_opt = true;
int rc, i, j;
phys_pg_pack = kzalloc(sizeof(*phys_pg_pack), GFP_KERNEL);
if (!phys_pg_pack)
return -ENOMEM;
phys_pg_pack->vm_type = userptr->vm_type;
phys_pg_pack->created_from_userptr = true;
phys_pg_pack->asid = ctx->asid;
atomic_set(&phys_pg_pack->mapping_cnt, 1);
/* Only if all dma_addrs are aligned to 2MB and their
* sizes is at least 2MB, we can use huge page mapping.
* We limit the 2MB optimization to this condition,
* since later on we acquire the related VA range as one
* consecutive block.
*/
total_npages = 0;
for_each_sg(userptr->sgt->sgl, sg, userptr->sgt->nents, i) {
npages = get_sg_info(sg, &dma_addr);
total_npages += npages;
if ((npages % PGS_IN_2MB_PAGE) ||
(dma_addr & (PAGE_SIZE_2MB - 1)))
is_huge_page_opt = false;
}
if (is_huge_page_opt) {
page_size = PAGE_SIZE_2MB;
total_npages /= PGS_IN_2MB_PAGE;
}
page_mask = ~(((u64) page_size) - 1);
phys_pg_pack->pages = kvmalloc_array(total_npages, sizeof(u64),
GFP_KERNEL);
if (!phys_pg_pack->pages) {
rc = -ENOMEM;
goto page_pack_arr_mem_err;
}
phys_pg_pack->npages = total_npages;
phys_pg_pack->page_size = page_size;
phys_pg_pack->total_size = total_npages * page_size;
j = 0;
for_each_sg(userptr->sgt->sgl, sg, userptr->sgt->nents, i) {
npages = get_sg_info(sg, &dma_addr);
/* align down to physical page size and save the offset */
if (first) {
first = false;
phys_pg_pack->offset = dma_addr & (page_size - 1);
dma_addr &= page_mask;
}
while (npages) {
phys_pg_pack->pages[j++] = dma_addr;
dma_addr += page_size;
if (is_huge_page_opt)
npages -= PGS_IN_2MB_PAGE;
else
npages--;
}
}
*pphys_pg_pack = phys_pg_pack;
return 0;
page_pack_arr_mem_err:
kfree(phys_pg_pack);
return rc;
}
/*
* map_phys_page_pack - maps the physical page pack
*
* @ctx : current context
* @vaddr : start address of the virtual area to map from
* @phys_pg_pack : the pack of physical pages to map to
*
* This function does the following:
* - Maps each chunk of virtual memory to matching physical chunk
* - Stores number of successful mappings in the given argument
* - Returns 0 on success, error code otherwise.
*/
static int map_phys_page_pack(struct hl_ctx *ctx, u64 vaddr,
struct hl_vm_phys_pg_pack *phys_pg_pack)
{
struct hl_device *hdev = ctx->hdev;
u64 next_vaddr = vaddr, paddr, mapped_pg_cnt = 0, i;
u32 page_size = phys_pg_pack->page_size;
int rc = 0;
for (i = 0 ; i < phys_pg_pack->npages ; i++) {
paddr = phys_pg_pack->pages[i];
rc = hl_mmu_map(ctx, next_vaddr, paddr, page_size);
if (rc) {
dev_err(hdev->dev,
"map failed for handle %u, npages: %llu, mapped: %llu",
phys_pg_pack->handle, phys_pg_pack->npages,
mapped_pg_cnt);
goto err;
}
mapped_pg_cnt++;
next_vaddr += page_size;
}
return 0;
err:
next_vaddr = vaddr;
for (i = 0 ; i < mapped_pg_cnt ; i++) {
if (hl_mmu_unmap(ctx, next_vaddr, page_size))
dev_warn_ratelimited(hdev->dev,
"failed to unmap handle %u, va: 0x%llx, pa: 0x%llx, page size: %u\n",
phys_pg_pack->handle, next_vaddr,
phys_pg_pack->pages[i], page_size);
next_vaddr += page_size;
}
return rc;
}
static int get_paddr_from_handle(struct hl_ctx *ctx, struct hl_mem_in *args,
u64 *paddr)
{
struct hl_device *hdev = ctx->hdev;
struct hl_vm *vm = &hdev->vm;
struct hl_vm_phys_pg_pack *phys_pg_pack;
u32 handle;
handle = lower_32_bits(args->map_device.handle);
spin_lock(&vm->idr_lock);
phys_pg_pack = idr_find(&vm->phys_pg_pack_handles, handle);
if (!phys_pg_pack) {
spin_unlock(&vm->idr_lock);
dev_err(hdev->dev, "no match for handle %u\n", handle);
return -EINVAL;
}
*paddr = phys_pg_pack->pages[0];
spin_unlock(&vm->idr_lock);
return 0;
}
/*
* map_device_va - map the given memory
*
* @ctx : current context
* @args : host parameters with handle/host virtual address
* @device_addr : pointer to result device virtual address
*
* This function does the following:
* - If given a physical device memory handle, map to a device virtual block
* and return the start address of this block
* - If given a host virtual address and size, find the related physical pages,
* map a device virtual block to this pages and return the start address of
* this block
*/
static int map_device_va(struct hl_ctx *ctx, struct hl_mem_in *args,
u64 *device_addr)
{
struct hl_device *hdev = ctx->hdev;
struct hl_vm *vm = &hdev->vm;
struct hl_vm_phys_pg_pack *phys_pg_pack;
struct hl_userptr *userptr = NULL;
struct hl_vm_hash_node *hnode;
enum vm_type_t *vm_type;
u64 ret_vaddr, hint_addr;
u32 handle = 0;
int rc;
bool is_userptr = args->flags & HL_MEM_USERPTR;
/* Assume failure */
*device_addr = 0;
if (is_userptr) {
rc = get_userptr_from_host_va(hdev, args, &userptr);
if (rc) {
dev_err(hdev->dev, "failed to get userptr from va\n");
return rc;
}
rc = init_phys_pg_pack_from_userptr(ctx, userptr,
&phys_pg_pack);
if (rc) {
dev_err(hdev->dev,
"unable to init page pack for vaddr 0x%llx\n",
args->map_host.host_virt_addr);
goto init_page_pack_err;
}
vm_type = (enum vm_type_t *) userptr;
hint_addr = args->map_host.hint_addr;
} else {
handle = lower_32_bits(args->map_device.handle);
spin_lock(&vm->idr_lock);
phys_pg_pack = idr_find(&vm->phys_pg_pack_handles, handle);
if (!phys_pg_pack) {
spin_unlock(&vm->idr_lock);
dev_err(hdev->dev,
"no match for handle %u\n", handle);
return -EINVAL;
}
/* increment now to avoid freeing device memory while mapping */
atomic_inc(&phys_pg_pack->mapping_cnt);
spin_unlock(&vm->idr_lock);
vm_type = (enum vm_type_t *) phys_pg_pack;
hint_addr = args->map_device.hint_addr;
}
/*
* relevant for mapping device physical memory only, as host memory is
* implicitly shared
*/
if (!is_userptr && !(phys_pg_pack->flags & HL_MEM_SHARED) &&
phys_pg_pack->asid != ctx->asid) {
dev_err(hdev->dev,
"Failed to map memory, handle %u is not shared\n",
handle);
rc = -EPERM;
goto shared_err;
}
hnode = kzalloc(sizeof(*hnode), GFP_KERNEL);
if (!hnode) {
rc = -ENOMEM;
goto hnode_err;
}
ret_vaddr = get_va_block(hdev,
is_userptr ? &ctx->host_va_range : &ctx->dram_va_range,
phys_pg_pack->total_size, hint_addr, is_userptr);
if (!ret_vaddr) {
dev_err(hdev->dev, "no available va block for handle %u\n",
handle);
rc = -ENOMEM;
goto va_block_err;
}
mutex_lock(&ctx->mmu_lock);
rc = map_phys_page_pack(ctx, ret_vaddr, phys_pg_pack);
if (rc) {
mutex_unlock(&ctx->mmu_lock);
dev_err(hdev->dev, "mapping page pack failed for handle %u\n",
handle);
goto map_err;
}
hdev->asic_funcs->mmu_invalidate_cache(hdev, false);
mutex_unlock(&ctx->mmu_lock);
ret_vaddr += phys_pg_pack->offset;
hnode->ptr = vm_type;
hnode->vaddr = ret_vaddr;
mutex_lock(&ctx->mem_hash_lock);
hash_add(ctx->mem_hash, &hnode->node, ret_vaddr);
mutex_unlock(&ctx->mem_hash_lock);
*device_addr = ret_vaddr;
if (is_userptr)
free_phys_pg_pack(hdev, phys_pg_pack);
return 0;
map_err:
if (add_va_block(hdev,
is_userptr ? &ctx->host_va_range : &ctx->dram_va_range,
ret_vaddr,
ret_vaddr + phys_pg_pack->total_size - 1))
dev_warn(hdev->dev,
"release va block failed for handle 0x%x, vaddr: 0x%llx\n",
handle, ret_vaddr);
va_block_err:
kfree(hnode);
hnode_err:
shared_err:
atomic_dec(&phys_pg_pack->mapping_cnt);
if (is_userptr)
free_phys_pg_pack(hdev, phys_pg_pack);
init_page_pack_err:
if (is_userptr)
free_userptr(hdev, userptr);
return rc;
}
/*
* unmap_device_va - unmap the given device virtual address
*
* @ctx : current context
* @vaddr : device virtual address to unmap
*
* This function does the following:
* - Unmap the physical pages related to the given virtual address
* - return the device virtual block to the virtual block list
*/
static int unmap_device_va(struct hl_ctx *ctx, u64 vaddr)
{
struct hl_device *hdev = ctx->hdev;
struct hl_vm_phys_pg_pack *phys_pg_pack = NULL;
struct hl_vm_hash_node *hnode = NULL;
struct hl_userptr *userptr = NULL;
enum vm_type_t *vm_type;
u64 next_vaddr, i;
u32 page_size;
bool is_userptr;
int rc;
/* protect from double entrance */
mutex_lock(&ctx->mem_hash_lock);
hash_for_each_possible(ctx->mem_hash, hnode, node, (unsigned long)vaddr)
if (vaddr == hnode->vaddr)
break;
if (!hnode) {
mutex_unlock(&ctx->mem_hash_lock);
dev_err(hdev->dev,
"unmap failed, no mem hnode for vaddr 0x%llx\n",
vaddr);
return -EINVAL;
}
hash_del(&hnode->node);
mutex_unlock(&ctx->mem_hash_lock);
vm_type = hnode->ptr;
if (*vm_type == VM_TYPE_USERPTR) {
is_userptr = true;
userptr = hnode->ptr;
rc = init_phys_pg_pack_from_userptr(ctx, userptr,
&phys_pg_pack);
if (rc) {
dev_err(hdev->dev,
"unable to init page pack for vaddr 0x%llx\n",
vaddr);
goto vm_type_err;
}
} else if (*vm_type == VM_TYPE_PHYS_PACK) {
is_userptr = false;
phys_pg_pack = hnode->ptr;
} else {
dev_warn(hdev->dev,
"unmap failed, unknown vm desc for vaddr 0x%llx\n",
vaddr);
rc = -EFAULT;
goto vm_type_err;
}
if (atomic_read(&phys_pg_pack->mapping_cnt) == 0) {
dev_err(hdev->dev, "vaddr 0x%llx is not mapped\n", vaddr);
rc = -EINVAL;
goto mapping_cnt_err;
}
page_size = phys_pg_pack->page_size;
vaddr &= ~(((u64) page_size) - 1);
next_vaddr = vaddr;
mutex_lock(&ctx->mmu_lock);
for (i = 0 ; i < phys_pg_pack->npages ; i++, next_vaddr += page_size) {
if (hl_mmu_unmap(ctx, next_vaddr, page_size))
dev_warn_ratelimited(hdev->dev,
"unmap failed for vaddr: 0x%llx\n", next_vaddr);
/* unmapping on Palladium can be really long, so avoid a CPU
* soft lockup bug by sleeping a little between unmapping pages
*/
if (hdev->pldm)
usleep_range(500, 1000);
}
hdev->asic_funcs->mmu_invalidate_cache(hdev, true);
mutex_unlock(&ctx->mmu_lock);
if (add_va_block(hdev,
is_userptr ? &ctx->host_va_range : &ctx->dram_va_range,
vaddr,
vaddr + phys_pg_pack->total_size - 1))
dev_warn(hdev->dev, "add va block failed for vaddr: 0x%llx\n",
vaddr);
atomic_dec(&phys_pg_pack->mapping_cnt);
kfree(hnode);
if (is_userptr) {
free_phys_pg_pack(hdev, phys_pg_pack);
free_userptr(hdev, userptr);
}
return 0;
mapping_cnt_err:
if (is_userptr)
free_phys_pg_pack(hdev, phys_pg_pack);
vm_type_err:
mutex_lock(&ctx->mem_hash_lock);
hash_add(ctx->mem_hash, &hnode->node, vaddr);
mutex_unlock(&ctx->mem_hash_lock);
return rc;
}
static int mem_ioctl_no_mmu(struct hl_fpriv *hpriv, union hl_mem_args *args)
{
struct hl_device *hdev = hpriv->hdev;
struct hl_ctx *ctx = hpriv->ctx;
u64 device_addr = 0;
u32 handle = 0;
int rc;
switch (args->in.op) {
case HL_MEM_OP_ALLOC:
if (args->in.alloc.mem_size == 0) {
dev_err(hdev->dev,
"alloc size must be larger than 0\n");
rc = -EINVAL;
goto out;
}
/* Force contiguous as there are no real MMU
* translations to overcome physical memory gaps
*/
args->in.flags |= HL_MEM_CONTIGUOUS;
rc = alloc_device_memory(ctx, &args->in, &handle);
memset(args, 0, sizeof(*args));
args->out.handle = (__u64) handle;
break;
case HL_MEM_OP_FREE:
rc = free_device_memory(ctx, args->in.free.handle);
break;
case HL_MEM_OP_MAP:
if (args->in.flags & HL_MEM_USERPTR) {
device_addr = args->in.map_host.host_virt_addr;
rc = 0;
} else {
rc = get_paddr_from_handle(ctx, &args->in,
&device_addr);
}
memset(args, 0, sizeof(*args));
args->out.device_virt_addr = device_addr;
break;
case HL_MEM_OP_UNMAP:
rc = 0;
break;
default:
dev_err(hdev->dev, "Unknown opcode for memory IOCTL\n");
rc = -ENOTTY;
break;
}
out:
return rc;
}
int hl_mem_ioctl(struct hl_fpriv *hpriv, void *data)
{
union hl_mem_args *args = data;
struct hl_device *hdev = hpriv->hdev;
struct hl_ctx *ctx = hpriv->ctx;
u64 device_addr = 0;
u32 handle = 0;
int rc;
if (hl_device_disabled_or_in_reset(hdev)) {
dev_warn_ratelimited(hdev->dev,
"Device is %s. Can't execute MEMORY IOCTL\n",
atomic_read(&hdev->in_reset) ? "in_reset" : "disabled");
return -EBUSY;
}
if (!hdev->mmu_enable)
return mem_ioctl_no_mmu(hpriv, args);
switch (args->in.op) {
case HL_MEM_OP_ALLOC:
if (!hdev->dram_supports_virtual_memory) {
dev_err(hdev->dev, "DRAM alloc is not supported\n");
rc = -EINVAL;
goto out;
}
if (args->in.alloc.mem_size == 0) {
dev_err(hdev->dev,
"alloc size must be larger than 0\n");
rc = -EINVAL;
goto out;
}
rc = alloc_device_memory(ctx, &args->in, &handle);
memset(args, 0, sizeof(*args));
args->out.handle = (__u64) handle;
break;
case HL_MEM_OP_FREE:
rc = free_device_memory(ctx, args->in.free.handle);
break;
case HL_MEM_OP_MAP:
rc = map_device_va(ctx, &args->in, &device_addr);
memset(args, 0, sizeof(*args));
args->out.device_virt_addr = device_addr;
break;
case HL_MEM_OP_UNMAP:
rc = unmap_device_va(ctx,
args->in.unmap.device_virt_addr);
break;
default:
dev_err(hdev->dev, "Unknown opcode for memory IOCTL\n");
rc = -ENOTTY;
break;
}
out:
return rc;
}
/*
* hl_pin_host_memory - pins a chunk of host memory
*
* @hdev : pointer to the habanalabs device structure
* @addr : the user-space virtual address of the memory area
* @size : the size of the memory area
* @userptr : pointer to hl_userptr structure
*
* This function does the following:
* - Pins the physical pages
* - Create a SG list from those pages
*/
int hl_pin_host_memory(struct hl_device *hdev, u64 addr, u64 size,
struct hl_userptr *userptr)
{
u64 start, end;
u32 npages, offset;
int rc;
if (!size) {
dev_err(hdev->dev, "size to pin is invalid - %llu\n", size);
return -EINVAL;
}
if (!access_ok((void __user *) (uintptr_t) addr, size)) {
dev_err(hdev->dev, "user pointer is invalid - 0x%llx\n", addr);
return -EFAULT;
}
/*
* If the combination of the address and size requested for this memory
* region causes an integer overflow, return error.
*/
if (((addr + size) < addr) ||
PAGE_ALIGN(addr + size) < (addr + size)) {
dev_err(hdev->dev,
"user pointer 0x%llx + %llu causes integer overflow\n",
addr, size);
return -EINVAL;
}
start = addr & PAGE_MASK;
offset = addr & ~PAGE_MASK;
end = PAGE_ALIGN(addr + size);
npages = (end - start) >> PAGE_SHIFT;
userptr->size = size;
userptr->addr = addr;
userptr->dma_mapped = false;
INIT_LIST_HEAD(&userptr->job_node);
userptr->vec = frame_vector_create(npages);
if (!userptr->vec) {
dev_err(hdev->dev, "Failed to create frame vector\n");
return -ENOMEM;
}
rc = get_vaddr_frames(start, npages, FOLL_FORCE | FOLL_WRITE,
userptr->vec);
if (rc != npages) {
dev_err(hdev->dev,
"Failed to map host memory, user ptr probably wrong\n");
if (rc < 0)
goto destroy_framevec;
rc = -EFAULT;
goto put_framevec;
}
if (frame_vector_to_pages(userptr->vec) < 0) {
dev_err(hdev->dev,
"Failed to translate frame vector to pages\n");
rc = -EFAULT;
goto put_framevec;
}
userptr->sgt = kzalloc(sizeof(*userptr->sgt), GFP_ATOMIC);
if (!userptr->sgt) {
rc = -ENOMEM;
goto put_framevec;
}
rc = sg_alloc_table_from_pages(userptr->sgt,
frame_vector_pages(userptr->vec),
npages, offset, size, GFP_ATOMIC);
if (rc < 0) {
dev_err(hdev->dev, "failed to create SG table from pages\n");
goto free_sgt;
}
hl_debugfs_add_userptr(hdev, userptr);
return 0;
free_sgt:
kfree(userptr->sgt);
put_framevec:
put_vaddr_frames(userptr->vec);
destroy_framevec:
frame_vector_destroy(userptr->vec);
return rc;
}
/*
* hl_unpin_host_memory - unpins a chunk of host memory
*
* @hdev : pointer to the habanalabs device structure
* @userptr : pointer to hl_userptr structure
*
* This function does the following:
* - Unpins the physical pages related to the host memory
* - Free the SG list
*/
int hl_unpin_host_memory(struct hl_device *hdev, struct hl_userptr *userptr)
{
struct page **pages;
hl_debugfs_remove_userptr(hdev, userptr);
if (userptr->dma_mapped)
hdev->asic_funcs->hl_dma_unmap_sg(hdev,
userptr->sgt->sgl,
userptr->sgt->nents,
userptr->dir);
pages = frame_vector_pages(userptr->vec);
if (!IS_ERR(pages)) {
int i;
for (i = 0; i < frame_vector_count(userptr->vec); i++)
set_page_dirty_lock(pages[i]);
}
put_vaddr_frames(userptr->vec);
frame_vector_destroy(userptr->vec);
list_del(&userptr->job_node);
sg_free_table(userptr->sgt);
kfree(userptr->sgt);
return 0;
}
/*
* hl_userptr_delete_list - clear userptr list
*
* @hdev : pointer to the habanalabs device structure
* @userptr_list : pointer to the list to clear
*
* This function does the following:
* - Iterates over the list and unpins the host memory and frees the userptr
* structure.
*/
void hl_userptr_delete_list(struct hl_device *hdev,
struct list_head *userptr_list)
{
struct hl_userptr *userptr, *tmp;
list_for_each_entry_safe(userptr, tmp, userptr_list, job_node) {
hl_unpin_host_memory(hdev, userptr);
kfree(userptr);
}
INIT_LIST_HEAD(userptr_list);
}
/*
* hl_userptr_is_pinned - returns whether the given userptr is pinned
*
* @hdev : pointer to the habanalabs device structure
* @userptr_list : pointer to the list to clear
* @userptr : pointer to userptr to check
*
* This function does the following:
* - Iterates over the list and checks if the given userptr is in it, means is
* pinned. If so, returns true, otherwise returns false.
*/
bool hl_userptr_is_pinned(struct hl_device *hdev, u64 addr,
u32 size, struct list_head *userptr_list,
struct hl_userptr **userptr)
{
list_for_each_entry((*userptr), userptr_list, job_node) {
if ((addr == (*userptr)->addr) && (size == (*userptr)->size))
return true;
}
return false;
}
/*
* hl_va_range_init - initialize virtual addresses range
*
* @hdev : pointer to the habanalabs device structure
* @va_range : pointer to the range to initialize
* @start : range start address
* @end : range end address
*
* This function does the following:
* - Initializes the virtual addresses list of the given range with the given
* addresses.
*/
static int hl_va_range_init(struct hl_device *hdev,
struct hl_va_range *va_range, u64 start, u64 end)
{
int rc;
INIT_LIST_HEAD(&va_range->list);
/* PAGE_SIZE alignment */
if (start & (PAGE_SIZE - 1)) {
start &= PAGE_MASK;
start += PAGE_SIZE;
}
if (end & (PAGE_SIZE - 1))
end &= PAGE_MASK;
if (start >= end) {
dev_err(hdev->dev, "too small vm range for va list\n");
return -EFAULT;
}
rc = add_va_block(hdev, va_range, start, end);
if (rc) {
dev_err(hdev->dev, "Failed to init host va list\n");
return rc;
}
va_range->start_addr = start;
va_range->end_addr = end;
return 0;
}
/*
* hl_vm_ctx_init_with_ranges - initialize virtual memory for context
*
* @ctx : pointer to the habanalabs context structure
* @host_range_start : host virtual addresses range start
* @host_range_end : host virtual addresses range end
* @dram_range_start : dram virtual addresses range start
* @dram_range_end : dram virtual addresses range end
*
* This function initializes the following:
* - MMU for context
* - Virtual address to area descriptor hashtable
* - Virtual block list of available virtual memory
*/
static int hl_vm_ctx_init_with_ranges(struct hl_ctx *ctx, u64 host_range_start,
u64 host_range_end, u64 dram_range_start,
u64 dram_range_end)
{
struct hl_device *hdev = ctx->hdev;
int rc;
rc = hl_mmu_ctx_init(ctx);
if (rc) {
dev_err(hdev->dev, "failed to init context %d\n", ctx->asid);
return rc;
}
mutex_init(&ctx->mem_hash_lock);
hash_init(ctx->mem_hash);
mutex_init(&ctx->host_va_range.lock);
rc = hl_va_range_init(hdev, &ctx->host_va_range, host_range_start,
host_range_end);
if (rc) {
dev_err(hdev->dev, "failed to init host vm range\n");
goto host_vm_err;
}
mutex_init(&ctx->dram_va_range.lock);
rc = hl_va_range_init(hdev, &ctx->dram_va_range, dram_range_start,
dram_range_end);
if (rc) {
dev_err(hdev->dev, "failed to init dram vm range\n");
goto dram_vm_err;
}
hl_debugfs_add_ctx_mem_hash(hdev, ctx);
return 0;
dram_vm_err:
mutex_destroy(&ctx->dram_va_range.lock);
mutex_lock(&ctx->host_va_range.lock);
clear_va_list_locked(hdev, &ctx->host_va_range.list);
mutex_unlock(&ctx->host_va_range.lock);
host_vm_err:
mutex_destroy(&ctx->host_va_range.lock);
mutex_destroy(&ctx->mem_hash_lock);
hl_mmu_ctx_fini(ctx);
return rc;
}
int hl_vm_ctx_init(struct hl_ctx *ctx)
{
struct asic_fixed_properties *prop = &ctx->hdev->asic_prop;
u64 host_range_start, host_range_end, dram_range_start,
dram_range_end;
atomic64_set(&ctx->dram_phys_mem, 0);
/*
* - If MMU is enabled, init the ranges as usual.
* - If MMU is disabled, in case of host mapping, the returned address
* is the given one.
* In case of DRAM mapping, the returned address is the physical
* address of the memory related to the given handle.
*/
if (ctx->hdev->mmu_enable) {
dram_range_start = prop->va_space_dram_start_address;
dram_range_end = prop->va_space_dram_end_address;
host_range_start = prop->va_space_host_start_address;
host_range_end = prop->va_space_host_end_address;
} else {
dram_range_start = prop->dram_user_base_address;
dram_range_end = prop->dram_end_address;
host_range_start = prop->dram_user_base_address;
host_range_end = prop->dram_end_address;
}
return hl_vm_ctx_init_with_ranges(ctx, host_range_start, host_range_end,
dram_range_start, dram_range_end);
}
/*
* hl_va_range_fini - clear a virtual addresses range
*
* @hdev : pointer to the habanalabs structure
* va_range : pointer to virtual addresses range
*
* This function initializes the following:
* - Checks that the given range contains the whole initial range
* - Frees the virtual addresses block list and its lock
*/
static void hl_va_range_fini(struct hl_device *hdev,
struct hl_va_range *va_range)
{
struct hl_vm_va_block *va_block;
if (list_empty(&va_range->list)) {
dev_warn(hdev->dev,
"va list should not be empty on cleanup!\n");
goto out;
}
if (!list_is_singular(&va_range->list)) {
dev_warn(hdev->dev,
"va list should not contain multiple blocks on cleanup!\n");
goto free_va_list;
}
va_block = list_first_entry(&va_range->list, typeof(*va_block), node);
if (va_block->start != va_range->start_addr ||
va_block->end != va_range->end_addr) {
dev_warn(hdev->dev,
"wrong va block on cleanup, from 0x%llx to 0x%llx\n",
va_block->start, va_block->end);
goto free_va_list;
}
free_va_list:
mutex_lock(&va_range->lock);
clear_va_list_locked(hdev, &va_range->list);
mutex_unlock(&va_range->lock);
out:
mutex_destroy(&va_range->lock);
}
/*
* hl_vm_ctx_fini - virtual memory teardown of context
*
* @ctx : pointer to the habanalabs context structure
*
* This function perform teardown the following:
* - Virtual block list of available virtual memory
* - Virtual address to area descriptor hashtable
* - MMU for context
*
* In addition this function does the following:
* - Unmaps the existing hashtable nodes if the hashtable is not empty. The
* hashtable should be empty as no valid mappings should exist at this
* point.
* - Frees any existing physical page list from the idr which relates to the
* current context asid.
* - This function checks the virtual block list for correctness. At this point
* the list should contain one element which describes the whole virtual
* memory range of the context. Otherwise, a warning is printed.
*/
void hl_vm_ctx_fini(struct hl_ctx *ctx)
{
struct hl_device *hdev = ctx->hdev;
struct hl_vm *vm = &hdev->vm;
struct hl_vm_phys_pg_pack *phys_pg_list;
struct hl_vm_hash_node *hnode;
struct hlist_node *tmp_node;
int i;
hl_debugfs_remove_ctx_mem_hash(hdev, ctx);
if (!hash_empty(ctx->mem_hash))
dev_notice(hdev->dev, "ctx is freed while it has va in use\n");
hash_for_each_safe(ctx->mem_hash, i, tmp_node, hnode, node) {
dev_dbg(hdev->dev,
"hl_mem_hash_node of vaddr 0x%llx of asid %d is still alive\n",
hnode->vaddr, ctx->asid);
unmap_device_va(ctx, hnode->vaddr);
}
spin_lock(&vm->idr_lock);
idr_for_each_entry(&vm->phys_pg_pack_handles, phys_pg_list, i)
if (phys_pg_list->asid == ctx->asid) {
dev_dbg(hdev->dev,
"page list 0x%p of asid %d is still alive\n",
phys_pg_list, ctx->asid);
atomic64_sub(phys_pg_list->total_size,
&hdev->dram_used_mem);
free_phys_pg_pack(hdev, phys_pg_list);
idr_remove(&vm->phys_pg_pack_handles, i);
}
spin_unlock(&vm->idr_lock);
hl_va_range_fini(hdev, &ctx->dram_va_range);
hl_va_range_fini(hdev, &ctx->host_va_range);
mutex_destroy(&ctx->mem_hash_lock);
hl_mmu_ctx_fini(ctx);
}
/*
* hl_vm_init - initialize virtual memory module
*
* @hdev : pointer to the habanalabs device structure
*
* This function initializes the following:
* - MMU module
* - DRAM physical pages pool of 2MB
* - Idr for device memory allocation handles
*/
int hl_vm_init(struct hl_device *hdev)
{
struct asic_fixed_properties *prop = &hdev->asic_prop;
struct hl_vm *vm = &hdev->vm;
int rc;
vm->dram_pg_pool = gen_pool_create(__ffs(prop->dram_page_size), -1);
if (!vm->dram_pg_pool) {
dev_err(hdev->dev, "Failed to create dram page pool\n");
return -ENOMEM;
}
kref_init(&vm->dram_pg_pool_refcount);
rc = gen_pool_add(vm->dram_pg_pool, prop->dram_user_base_address,
prop->dram_end_address - prop->dram_user_base_address,
-1);
if (rc) {
dev_err(hdev->dev,
"Failed to add memory to dram page pool %d\n", rc);
goto pool_add_err;
}
spin_lock_init(&vm->idr_lock);
idr_init(&vm->phys_pg_pack_handles);
atomic64_set(&hdev->dram_used_mem, 0);
vm->init_done = true;
return 0;
pool_add_err:
gen_pool_destroy(vm->dram_pg_pool);
return rc;
}
/*
* hl_vm_fini - virtual memory module teardown
*
* @hdev : pointer to the habanalabs device structure
*
* This function perform teardown to the following:
* - Idr for device memory allocation handles
* - DRAM physical pages pool of 2MB
* - MMU module
*/
void hl_vm_fini(struct hl_device *hdev)
{
struct hl_vm *vm = &hdev->vm;
if (!vm->init_done)
return;
/*
* At this point all the contexts should be freed and hence no DRAM
* memory should be in use. Hence the DRAM pool should be freed here.
*/
if (kref_put(&vm->dram_pg_pool_refcount, dram_pg_pool_do_release) != 1)
dev_warn(hdev->dev, "dram_pg_pool was not destroyed on %s\n",
__func__);
vm->init_done = false;
}