// 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;
}