Merge tag 'drm-next-2021-09-10' of git://anongit.freedesktop.org/drm/drm

[linux-2.6-microblaze.git] / drivers / misc / habanalabs / common / memory.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>

#define HL_MMU_DEBUG    0

/* use small pages for supporting non-pow2 (32M/40M/48M) DRAM phys page sizes */
#define DRAM_POOL_PAGE_SIZE SZ_8M

/*
 * 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: pointer to the context structure.
 * @args: host parameters containing the requested size.
 * @ret_handle: result handle.
 *
 * This function does the following:
 * - Allocate the requested size rounded up to 'dram_page_size' pages.
 * - Return unique handle for later map/unmap/free.
 */
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;
        int handle, rc;
        bool contiguous;

        num_curr_pgs = 0;
        page_size = hdev->asic_prop.dram_page_size;
        num_pgs = DIV_ROUND_UP_ULL(args->alloc.mem_size, page_size);
        total_size = num_pgs * page_size;

        if (!total_size) {
                dev_err(hdev->dev, "Cannot allocate 0 bytes\n");
                return -EINVAL;
        }

        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 contiguous pages with total size of %llu\n",
                                num_pgs, total_size);
                        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 (ZERO_OR_NULL_PTR(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_KERNEL);
        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;
}

/**
 * dma_map_host_va() - DMA mapping of the given host virtual address.
 * @hdev: habanalabs device structure.
 * @addr: the host virtual address of the memory area.
 * @size: the size of the memory area.
 * @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 dma_map_host_va(struct hl_device *hdev, u64 addr, u64 size,
                                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, addr, 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;
}

/**
 * dma_unmap_host_va() - DMA unmapping of the given host virtual address.
 * @hdev: habanalabs device structure.
 * @userptr: userptr to free.
 *
 * This function does the following:
 * - Unpins the physical pages.
 * - Frees the userptr structure.
 */
static void dma_unmap_host_va(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, scrub and free each physical block structure by
 *     returning it to the general pool.
 *     In case of error during scrubbing, initiate hard reset.
 *     Once hard reset is triggered, scrubbing is bypassed while freeing the
 *     memory continues.
 * - Free the hl_vm_phys_pg_pack structure.
 */
static int 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;
        int rc = 0;

        if (phys_pg_pack->created_from_userptr)
                goto end;

        if (phys_pg_pack->contiguous) {
                if (hdev->memory_scrub && !hdev->disabled) {
                        rc = hdev->asic_funcs->scrub_device_mem(hdev,
                                        phys_pg_pack->pages[0],
                                        phys_pg_pack->total_size);
                        if (rc)
                                dev_err(hdev->dev,
                                        "Failed to scrub contiguous device memory\n");
                }

                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++) {
                        if (hdev->memory_scrub && !hdev->disabled && rc == 0) {
                                rc = hdev->asic_funcs->scrub_device_mem(
                                                hdev,
                                                phys_pg_pack->pages[i],
                                                phys_pg_pack->page_size);
                                if (rc)
                                        dev_err(hdev->dev,
                                                "Failed to scrub device memory\n");
                        }
                        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);
                }
        }

        if (rc && !hdev->disabled)
                hl_device_reset(hdev, HL_RESET_HARD);

end:
        kvfree(phys_pg_pack->pages);
        kfree(phys_pg_pack);

        return rc;
}

/**
 * free_device_memory() - free device memory.
 * @ctx: pointer to the context structure.
 * @args: host parameters containing the requested size.
 *
 * This function does the following:
 * - Free the device memory related to the given handle.
 */
static int free_device_memory(struct hl_ctx *ctx, struct hl_mem_in *args)
{
        struct hl_device *hdev = ctx->hdev;
        struct hl_vm *vm = &hdev->vm;
        struct hl_vm_phys_pg_pack *phys_pg_pack;
        u32 handle = args->free.handle;

        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);

                return 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 for the given size and alignment.
 *
 * @hdev: pointer to the habanalabs device structure.
 * @va_range: pointer to the virtual addresses range.
 * @size: requested block size.
 * @hint_addr: hint for requested address by the user.
 * @va_block_align: required alignment of the virtual block start address.
 *
 * This function does the following:
 * - Iterate on the virtual block list to find a suitable virtual block for the
 *   given size, hint address and alignment.
 * - 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, u32 va_block_align)
{
        struct hl_vm_va_block *va_block, *new_va_block = NULL;
        u64 tmp_hint_addr, valid_start, valid_size, prev_start, prev_end,
                align_mask, reserved_valid_start = 0, reserved_valid_size = 0;
        bool add_prev = false;
        bool is_align_pow_2  = is_power_of_2(va_range->page_size);

        if (is_align_pow_2)
                align_mask = ~((u64)va_block_align - 1);
        else
                /*
                 * with non-power-of-2 range we work only with page granularity
                 * and the start address is page aligned,
                 * so no need for alignment checking.
                 */
                size = DIV_ROUND_UP_ULL(size, va_range->page_size) *
                                                        va_range->page_size;

        tmp_hint_addr = hint_addr;

        /* Check if we need to ignore hint address */
        if ((is_align_pow_2 && (hint_addr & (va_block_align - 1))) ||
                        (!is_align_pow_2 &&
                                do_div(tmp_hint_addr, va_range->page_size))) {

                dev_dbg(hdev->dev,
                        "Hint address 0x%llx will be ignored because it is not aligned\n",
                        hint_addr);
                hint_addr = 0;
        }

        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 (is_align_pow_2 && (valid_start & (va_block_align - 1))) {
                        valid_start &= align_mask;
                        valid_start += va_block_align;
                        if (valid_start > va_block->end)
                                continue;
                }

                valid_size = va_block->end - valid_start;
                if (valid_size < size)
                        continue;

                /* Pick the minimal length block which has the required size */
                if (!new_va_block || (valid_size < reserved_valid_size)) {
                        new_va_block = va_block;
                        reserved_valid_start = valid_start;
                        reserved_valid_size = valid_size;
                }

                if (hint_addr && hint_addr >= valid_start &&
                                        (hint_addr + size) <= va_block->end) {
                        new_va_block = va_block;
                        reserved_valid_start = hint_addr;
                        reserved_valid_size = valid_size;
                        break;
                }
        }

        if (!new_va_block) {
                dev_err(hdev->dev, "no available va block for size %llu\n",
                                                                size);
                goto out;
        }

        /*
         * Check if there is some leftover range due to reserving the new
         * va block, then return it to the main virtual addresses list.
         */
        if (reserved_valid_start > new_va_block->start) {
                prev_start = new_va_block->start;
                prev_end = reserved_valid_start - 1;

                new_va_block->start = reserved_valid_start;
                new_va_block->size = reserved_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 reserved_valid_start;
}

/*
 * hl_reserve_va_block() - reserve a virtual block of a given size.
 * @hdev: pointer to the habanalabs device structure.
 * @ctx: current context
 * @type: virtual addresses range type.
 * @size: requested block size.
 * @alignment: required alignment in bytes of the virtual block start address,
 *             0 means no alignment.
 *
 * This function does the following:
 * - Iterate on the virtual block list to find a suitable virtual block for the
 *   given size and alignment.
 * - Reserve the requested block and update the list.
 * - Return the start address of the virtual block.
 */
u64 hl_reserve_va_block(struct hl_device *hdev, struct hl_ctx *ctx,
                enum hl_va_range_type type, u32 size, u32 alignment)
{
        return get_va_block(hdev, ctx->va_range[type], size, 0,
                        max(alignment, ctx->va_range[type]->page_size));
}

/**
 * hl_get_va_range_type() - get va_range type for the given address and size.
 * @address: the start address of the area we want to validate.
 * @size: the size in bytes of the area we want to validate.
 * @type: returned va_range type.
 *
 * Return: true if the area is inside a valid range, false otherwise.
 */
static int hl_get_va_range_type(struct hl_ctx *ctx, u64 address, u64 size,
                        enum hl_va_range_type *type)
{
        int i;

        for (i = 0 ; i < HL_VA_RANGE_TYPE_MAX; i++) {
                if (hl_mem_area_inside_range(address, size,
                                ctx->va_range[i]->start_addr,
                                ctx->va_range[i]->end_addr)) {
                        *type = i;
                        return 0;
                }
        }

        return -EINVAL;
}

/**
 * hl_unreserve_va_block() - wrapper for add_va_block to unreserve a va block.
 * @hdev: pointer to the habanalabs device structure
 * @ctx: pointer to the context structure.
 * @start: start virtual address.
 * @end: end virtual address.
 *
 * This function does the following:
 * - Takes the list lock and calls add_va_block_locked.
 */
int hl_unreserve_va_block(struct hl_device *hdev, struct hl_ctx *ctx,
                u64 start_addr, u64 size)
{
        enum hl_va_range_type type;
        int rc;

        rc = hl_get_va_range_type(ctx, start_addr, size, &type);
        if (rc) {
                dev_err(hdev->dev,
                        "cannot find va_range for va %#llx size %llu",
                        start_addr, size);
                return rc;
        }

        rc = add_va_block(hdev, ctx->va_range[type], start_addr,
                                                start_addr + size - 1);
        if (rc)
                dev_warn(hdev->dev,
                        "add va block failed for vaddr: 0x%llx\n", start_addr);

        return rc;
}

/**
 * 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: pointer to the context structure.
 * @userptr: userptr to initialize from.
 * @pphys_pg_pack: result 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,
                huge_page_size = ctx->hdev->asic_prop.pmmu_huge.page_size;
        bool first = true, is_huge_page_opt = true;
        int rc, i, j;
        u32 pgs_in_huge_page = huge_page_size >> __ffs(page_size);

        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_huge_page) ||
                                        (dma_addr & (huge_page_size - 1)))
                        is_huge_page_opt = false;
        }

        if (is_huge_page_opt) {
                page_size = huge_page_size;
                do_div(total_npages, pgs_in_huge_page);
        }

        page_mask = ~(((u64) page_size) - 1);

        phys_pg_pack->pages = kvmalloc_array(total_npages, sizeof(u64),
                                                GFP_KERNEL);
        if (ZERO_OR_NULL_PTR(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_huge_page;
                        else
                                npages--;
                }
        }

        *pphys_pg_pack = phys_pg_pack;

        return 0;

page_pack_arr_mem_err:
        kfree(phys_pg_pack);

        return rc;
}

/**
 * map_phys_pg_pack() - maps the physical page pack..
 * @ctx: pointer to the context structure.
 * @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_pg_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;
        bool is_host_addr;

        for (i = 0 ; i < phys_pg_pack->npages ; i++) {
                paddr = phys_pg_pack->pages[i];

                rc = hl_mmu_map_page(ctx, next_vaddr, paddr, page_size,
                                (i + 1) == phys_pg_pack->npages);
                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:
        is_host_addr = !hl_is_dram_va(hdev, vaddr);

        next_vaddr = vaddr;
        for (i = 0 ; i < mapped_pg_cnt ; i++) {
                if (hl_mmu_unmap_page(ctx, next_vaddr, page_size,
                                        (i + 1) == mapped_pg_cnt))
                        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;

                /*
                 * unmapping on Palladium can be really long, so avoid a CPU
                 * soft lockup bug by sleeping a little between unmapping pages
                 *
                 * In addition, on host num of pages could be huge,
                 * because page size could be 4KB, so when unmapping host
                 * pages sleep every 32K pages to avoid soft lockup
                 */
                if (hdev->pldm || (is_host_addr && (i & 0x7FFF) == 0))
                        usleep_range(50, 200);
        }

        return rc;
}

/**
 * unmap_phys_pg_pack() - unmaps the physical page pack.
 * @ctx: pointer to the context structure.
 * @vaddr: start address of the virtual area to unmap.
 * @phys_pg_pack: the pack of physical pages to unmap.
 */
static void unmap_phys_pg_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, i;
        bool is_host_addr;
        u32 page_size;

        is_host_addr = !hl_is_dram_va(hdev, vaddr);
        page_size = phys_pg_pack->page_size;
        next_vaddr = vaddr;

        for (i = 0 ; i < phys_pg_pack->npages ; i++, next_vaddr += page_size) {
                if (hl_mmu_unmap_page(ctx, next_vaddr, page_size,
                                       (i + 1) == phys_pg_pack->npages))
                        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
                 *
                 * In addition, on host num of pages could be huge,
                 * because page size could be 4KB, so when unmapping host
                 * pages sleep every 32K pages to avoid soft lockup
                 */
                if (hdev->pldm || (is_host_addr && (i & 0x7FFF) == 0))
                        usleep_range(50, 200);
        }
}

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: pointer to the context structure.
 * @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;
        struct hl_va_range *va_range;
        enum vm_type_t *vm_type;
        u64 ret_vaddr, hint_addr;
        u32 handle = 0, va_block_align;
        int rc;
        bool is_userptr = args->flags & HL_MEM_USERPTR;

        /* Assume failure */
        *device_addr = 0;

        if (is_userptr) {
                u64 addr = args->map_host.host_virt_addr,
                        size = args->map_host.mem_size;
                u32 page_size = hdev->asic_prop.pmmu.page_size,
                        huge_page_size = hdev->asic_prop.pmmu_huge.page_size;

                rc = dma_map_host_va(hdev, addr, size, &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",
                                addr);
                        goto init_page_pack_err;
                }

                vm_type = (enum vm_type_t *) userptr;
                hint_addr = args->map_host.hint_addr;
                handle = phys_pg_pack->handle;

                /* get required alignment */
                if (phys_pg_pack->page_size == page_size) {
                        va_range = ctx->va_range[HL_VA_RANGE_TYPE_HOST];

                        /*
                         * huge page alignment may be needed in case of regular
                         * page mapping, depending on the host VA alignment
                         */
                        if (addr & (huge_page_size - 1))
                                va_block_align = page_size;
                        else
                                va_block_align = huge_page_size;
                } else {
                        /*
                         * huge page alignment is needed in case of huge page
                         * mapping
                         */
                        va_range = ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE];
                        va_block_align = huge_page_size;
                }
        } 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;

                /* DRAM VA alignment is the same as the MMU page size */
                va_range = ctx->va_range[HL_VA_RANGE_TYPE_DRAM];
                va_block_align = hdev->asic_prop.dmmu.page_size;
        }

        /*
         * 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, va_range, phys_pg_pack->total_size,
                                        hint_addr, va_block_align);
        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_pg_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;
        }

        rc = hdev->asic_funcs->mmu_invalidate_cache_range(hdev, false,
                *vm_type, ctx->asid, ret_vaddr, phys_pg_pack->total_size);

        mutex_unlock(&ctx->mmu_lock);

        if (rc) {
                dev_err(hdev->dev,
                        "mapping handle %u failed due to MMU cache invalidation\n",
                        handle);
                goto map_err;
        }

        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)
                rc = free_phys_pg_pack(hdev, phys_pg_pack);

        return rc;

map_err:
        if (add_va_block(hdev, 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)
                dma_unmap_host_va(hdev, userptr);

        return rc;
}

/**
 * unmap_device_va() - unmap the given device virtual address.
 * @ctx: pointer to the context structure.
 * @args: host parameters with device virtual address to unmap.
 * @ctx_free: true if in context free flow, false otherwise.
 *
 * 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, struct hl_mem_in *args,
                                bool ctx_free)
{
        struct hl_device *hdev = ctx->hdev;
        struct asic_fixed_properties *prop = &hdev->asic_prop;
        struct hl_vm_phys_pg_pack *phys_pg_pack = NULL;
        struct hl_vm_hash_node *hnode = NULL;
        struct hl_userptr *userptr = NULL;
        struct hl_va_range *va_range;
        u64 vaddr = args->unmap.device_virt_addr;
        enum vm_type_t *vm_type;
        bool is_userptr;
        int rc = 0;

        /* 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;
                }

                if (phys_pg_pack->page_size ==
                                        hdev->asic_prop.pmmu.page_size)
                        va_range = ctx->va_range[HL_VA_RANGE_TYPE_HOST];
                else
                        va_range = ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE];
        } else if (*vm_type == VM_TYPE_PHYS_PACK) {
                is_userptr = false;
                va_range = ctx->va_range[HL_VA_RANGE_TYPE_DRAM];
                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;
        }

        if (!is_userptr && !is_power_of_2(phys_pg_pack->page_size))
                vaddr = prop->dram_base_address +
                        DIV_ROUND_DOWN_ULL(vaddr - prop->dram_base_address,
                                                phys_pg_pack->page_size) *
                                                        phys_pg_pack->page_size;
        else
                vaddr &= ~(((u64) phys_pg_pack->page_size) - 1);

        mutex_lock(&ctx->mmu_lock);

        unmap_phys_pg_pack(ctx, vaddr, phys_pg_pack);

        /*
         * During context free this function is called in a loop to clean all
         * the context mappings. Hence the cache invalidation can be called once
         * at the loop end rather than for each iteration
         */
        if (!ctx_free)
                rc = hdev->asic_funcs->mmu_invalidate_cache_range(hdev, true,
                                *vm_type, ctx->asid, vaddr,
                                phys_pg_pack->total_size);

        mutex_unlock(&ctx->mmu_lock);

        /*
         * If the context is closing we don't need to check for the MMU cache
         * invalidation return code and update the VA free list as in this flow
         * we invalidate the MMU cache outside of this unmap function and the VA
         * free list will be freed anyway.
         */
        if (!ctx_free) {
                int tmp_rc;

                if (rc)
                        dev_err(hdev->dev,
                                "unmapping vaddr 0x%llx failed due to MMU cache invalidation\n",
                                vaddr);

                tmp_rc = add_va_block(hdev, va_range, vaddr,
                                        vaddr + phys_pg_pack->total_size - 1);
                if (tmp_rc) {
                        dev_warn(hdev->dev,
                                        "add va block failed for vaddr: 0x%llx\n",
                                        vaddr);
                        if (!rc)
                                rc = tmp_rc;
                }
        }

        atomic_dec(&phys_pg_pack->mapping_cnt);
        kfree(hnode);

        if (is_userptr) {
                rc = free_phys_pg_pack(hdev, phys_pg_pack);
                dma_unmap_host_va(hdev, userptr);
        }

        return rc;

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 map_block(struct hl_device *hdev, u64 address, u64 *handle,
                        u32 *size)
{
        u32 block_id = 0;
        int rc;

        rc = hdev->asic_funcs->get_hw_block_id(hdev, address, size, &block_id);

        *handle = block_id | HL_MMAP_TYPE_BLOCK;
        *handle <<= PAGE_SHIFT;

        return rc;
}

static void hw_block_vm_close(struct vm_area_struct *vma)
{
        struct hl_vm_hw_block_list_node *lnode =
                (struct hl_vm_hw_block_list_node *) vma->vm_private_data;
        struct hl_ctx *ctx = lnode->ctx;

        mutex_lock(&ctx->hw_block_list_lock);
        list_del(&lnode->node);
        mutex_unlock(&ctx->hw_block_list_lock);
        hl_ctx_put(ctx);
        kfree(lnode);
        vma->vm_private_data = NULL;
}

static const struct vm_operations_struct hw_block_vm_ops = {
        .close = hw_block_vm_close
};

/**
 * hl_hw_block_mmap() - mmap a hw block to user.
 * @hpriv: pointer to the private data of the fd
 * @vma: pointer to vm_area_struct of the process
 *
 * Driver increments context reference for every HW block mapped in order
 * to prevent user from closing FD without unmapping first
 */
int hl_hw_block_mmap(struct hl_fpriv *hpriv, struct vm_area_struct *vma)
{
        struct hl_vm_hw_block_list_node *lnode;
        struct hl_device *hdev = hpriv->hdev;
        struct hl_ctx *ctx = hpriv->ctx;
        u32 block_id, block_size;
        int rc;

        /* We use the page offset to hold the block id and thus we need to clear
         * it before doing the mmap itself
         */
        block_id = vma->vm_pgoff;
        vma->vm_pgoff = 0;

        /* Driver only allows mapping of a complete HW block */
        block_size = vma->vm_end - vma->vm_start;

        if (!access_ok((void __user *) (uintptr_t) vma->vm_start, block_size)) {
                dev_err(hdev->dev,
                        "user pointer is invalid - 0x%lx\n",
                        vma->vm_start);

                return -EINVAL;
        }

        lnode = kzalloc(sizeof(*lnode), GFP_KERNEL);
        if (!lnode)
                return -ENOMEM;

        vma->vm_ops = &hw_block_vm_ops;
        vma->vm_private_data = lnode;

        hl_ctx_get(hdev, ctx);

        rc = hdev->asic_funcs->hw_block_mmap(hdev, vma, block_id, block_size);
        if (rc) {
                hl_ctx_put(ctx);
                kfree(lnode);
                return rc;
        }

        lnode->ctx = ctx;
        lnode->vaddr = vma->vm_start;
        lnode->size = block_size;
        lnode->id = block_id;

        mutex_lock(&ctx->hw_block_list_lock);
        list_add_tail(&lnode->node, &ctx->hw_block_mem_list);
        mutex_unlock(&ctx->hw_block_list_lock);

        vma->vm_pgoff = block_id;

        return 0;
}

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 block_handle, device_addr = 0;
        u32 handle = 0, block_size;
        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);
                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;

        case HL_MEM_OP_MAP_BLOCK:
                rc = map_block(hdev, args->in.map_block.block_addr,
                                &block_handle, &block_size);
                args->out.block_handle = block_handle;
                args->out.block_size = block_size;
                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)
{
        enum hl_device_status status;
        union hl_mem_args *args = data;
        struct hl_device *hdev = hpriv->hdev;
        struct hl_ctx *ctx = hpriv->ctx;
        u64 block_handle, device_addr = 0;
        u32 handle = 0, block_size;
        int rc;

        if (!hl_device_operational(hdev, &status)) {
                dev_warn_ratelimited(hdev->dev,
                        "Device is %s. Can't execute MEMORY IOCTL\n",
                        hdev->status[status]);
                return -EBUSY;
        }

        if (!hdev->mmu_enable)
                return mem_ioctl_no_mmu(hpriv, args);

        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;
                }

                /* If DRAM does not support virtual memory the driver won't
                 * handle the allocation/freeing of that memory. However, for
                 * system administration/monitoring purposes, the driver will
                 * keep track of the amount of DRAM memory that is allocated
                 * and freed by the user. Because this code totally relies on
                 * the user's input, the driver can't ensure the validity
                 * of this accounting.
                 */
                if (!hdev->asic_prop.dram_supports_virtual_memory) {
                        atomic64_add(args->in.alloc.mem_size,
                                        &ctx->dram_phys_mem);
                        atomic64_add(args->in.alloc.mem_size,
                                        &hdev->dram_used_mem);

                        dev_dbg(hdev->dev, "DRAM alloc is not supported\n");
                        rc = 0;

                        memset(args, 0, sizeof(*args));
                        args->out.handle = 0;
                        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:
                /* If DRAM does not support virtual memory the driver won't
                 * handle the allocation/freeing of that memory. However, for
                 * system administration/monitoring purposes, the driver will
                 * keep track of the amount of DRAM memory that is allocated
                 * and freed by the user. Because this code totally relies on
                 * the user's input, the driver can't ensure the validity
                 * of this accounting.
                 */
                if (!hdev->asic_prop.dram_supports_virtual_memory) {
                        atomic64_sub(args->in.alloc.mem_size,
                                        &ctx->dram_phys_mem);
                        atomic64_sub(args->in.alloc.mem_size,
                                        &hdev->dram_used_mem);

                        dev_dbg(hdev->dev, "DRAM alloc is not supported\n");
                        rc = 0;

                        goto out;
                }

                rc = free_device_memory(ctx, &args->in);
                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, false);
                break;

        case HL_MEM_OP_MAP_BLOCK:
                rc = map_block(hdev, args->in.map_block.block_addr,
                                &block_handle, &block_size);
                args->out.block_handle = block_handle;
                args->out.block_size = block_size;
                break;

        default:
                dev_err(hdev->dev, "Unknown opcode for memory IOCTL\n");
                rc = -ENOTTY;
                break;
        }

out:
        return rc;
}

static int get_user_memory(struct hl_device *hdev, u64 addr, u64 size,
                                u32 npages, u64 start, u32 offset,
                                struct hl_userptr *userptr)
{
        int rc;

        if (!access_ok((void __user *) (uintptr_t) addr, size)) {
                dev_err(hdev->dev, "user pointer is invalid - 0x%llx\n", addr);
                return -EFAULT;
        }

        userptr->pages = kvmalloc_array(npages, sizeof(*userptr->pages),
                                        GFP_KERNEL);
        if (!userptr->pages)
                return -ENOMEM;

        rc = pin_user_pages_fast(start, npages,
                                 FOLL_FORCE | FOLL_WRITE | FOLL_LONGTERM,
                                 userptr->pages);

        if (rc != npages) {
                dev_err(hdev->dev,
                        "Failed (%d) to pin host memory with user ptr 0x%llx, size 0x%llx, npages %d\n",
                        rc, addr, size, npages);
                if (rc < 0)
                        goto destroy_pages;
                npages = rc;
                rc = -EFAULT;
                goto put_pages;
        }
        userptr->npages = npages;

        rc = sg_alloc_table_from_pages(userptr->sgt,
                                       userptr->pages,
                                       npages, offset, size, GFP_KERNEL);
        if (rc < 0) {
                dev_err(hdev->dev, "failed to create SG table from pages\n");
                goto put_pages;
        }

        return 0;

put_pages:
        unpin_user_pages(userptr->pages, npages);
destroy_pages:
        kvfree(userptr->pages);
        return rc;
}

/**
 * hl_pin_host_memory() - pins a chunk of host memory.
 * @hdev: pointer to the habanalabs device structure.
 * @addr: the host 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 an 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 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;
        }

        userptr->sgt = kzalloc(sizeof(*userptr->sgt), GFP_KERNEL);
        if (!userptr->sgt)
                return -ENOMEM;

        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);

        rc = get_user_memory(hdev, addr, size, npages, start, offset,
                                userptr);
        if (rc) {
                dev_err(hdev->dev,
                        "failed to get user memory for address 0x%llx\n",
                        addr);
                goto free_sgt;
        }

        hl_debugfs_add_userptr(hdev, userptr);

        return 0;

free_sgt:
        kfree(userptr->sgt);
        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
 */
void hl_unpin_host_memory(struct hl_device *hdev, struct hl_userptr *userptr)
{
        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);

        unpin_user_pages_dirty_lock(userptr->pages, userptr->npages, true);
        kvfree(userptr->pages);

        list_del(&userptr->job_node);

        sg_free_table(userptr->sgt);
        kfree(userptr->sgt);
}

/**
 * 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;
}

/**
 * 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 va_range_init(struct hl_device *hdev, struct hl_va_range *va_range,
                                u64 start, u64 end, u32 page_size)
{
        int rc;

        INIT_LIST_HEAD(&va_range->list);

        /*
         * PAGE_SIZE alignment
         * it is the callers responsibility to align the addresses if the
         * page size is not a power of 2
         */

        if (is_power_of_2(page_size)) {
                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;
        va_range->page_size = page_size;

        return 0;
}

/**
 * va_range_fini() - clear a virtual addresses range.
 * @hdev: pointer to the habanalabs structure.
 * va_range: pointer to virtual addresses rang.e
 *
 * This function does the following:
 * - Frees the virtual addresses block list and its lock.
 */
static void va_range_fini(struct hl_device *hdev, struct hl_va_range *va_range)
{
        mutex_lock(&va_range->lock);
        clear_va_list_locked(hdev, &va_range->list);
        mutex_unlock(&va_range->lock);

        mutex_destroy(&va_range->lock);
        kfree(va_range);
}

/**
 * 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.
 * @host_huge_range_start: host virtual addresses range start for memory
 *                         allocated with huge pages.
 * @host_huge_range_end: host virtual addresses range end for memory allocated
 *                        with huge pages.
 * @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 vm_ctx_init_with_ranges(struct hl_ctx *ctx,
                                        u64 host_range_start,
                                        u64 host_range_end,
                                        u32 host_page_size,
                                        u64 host_huge_range_start,
                                        u64 host_huge_range_end,
                                        u32 host_huge_page_size,
                                        u64 dram_range_start,
                                        u64 dram_range_end,
                                        u32 dram_page_size)
{
        struct hl_device *hdev = ctx->hdev;
        int i, rc;

        for (i = 0 ; i < HL_VA_RANGE_TYPE_MAX ; i++) {
                ctx->va_range[i] =
                        kzalloc(sizeof(struct hl_va_range), GFP_KERNEL);
                if (!ctx->va_range[i]) {
                        rc = -ENOMEM;
                        goto free_va_range;
                }
        }

        rc = hl_mmu_ctx_init(ctx);
        if (rc) {
                dev_err(hdev->dev, "failed to init context %d\n", ctx->asid);
                goto free_va_range;
        }

        mutex_init(&ctx->mem_hash_lock);
        hash_init(ctx->mem_hash);

        mutex_init(&ctx->va_range[HL_VA_RANGE_TYPE_HOST]->lock);

        rc = va_range_init(hdev, ctx->va_range[HL_VA_RANGE_TYPE_HOST],
                        host_range_start, host_range_end, host_page_size);
        if (rc) {
                dev_err(hdev->dev, "failed to init host vm range\n");
                goto mmu_ctx_fini;
        }

        if (hdev->pmmu_huge_range) {
                mutex_init(&ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE]->lock);

                rc = va_range_init(hdev,
                        ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE],
                        host_huge_range_start, host_huge_range_end,
                        host_huge_page_size);
                if (rc) {
                        dev_err(hdev->dev,
                                "failed to init host huge vm range\n");
                        goto clear_host_va_range;
                }
        } else {
                kfree(ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE]);
                ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE] =
                                ctx->va_range[HL_VA_RANGE_TYPE_HOST];
        }

        mutex_init(&ctx->va_range[HL_VA_RANGE_TYPE_DRAM]->lock);

        rc = va_range_init(hdev, ctx->va_range[HL_VA_RANGE_TYPE_DRAM],
                        dram_range_start, dram_range_end, dram_page_size);
        if (rc) {
                dev_err(hdev->dev, "failed to init dram vm range\n");
                goto clear_host_huge_va_range;
        }

        hl_debugfs_add_ctx_mem_hash(hdev, ctx);

        return 0;

clear_host_huge_va_range:
        mutex_destroy(&ctx->va_range[HL_VA_RANGE_TYPE_DRAM]->lock);

        if (hdev->pmmu_huge_range) {
                mutex_lock(&ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE]->lock);
                clear_va_list_locked(hdev,
                        &ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE]->list);
                mutex_unlock(&ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE]->lock);
        }
clear_host_va_range:
        if (hdev->pmmu_huge_range)
                mutex_destroy(&ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE]->lock);
        mutex_lock(&ctx->va_range[HL_VA_RANGE_TYPE_HOST]->lock);
        clear_va_list_locked(hdev, &ctx->va_range[HL_VA_RANGE_TYPE_HOST]->list);
        mutex_unlock(&ctx->va_range[HL_VA_RANGE_TYPE_HOST]->lock);
mmu_ctx_fini:
        mutex_destroy(&ctx->va_range[HL_VA_RANGE_TYPE_HOST]->lock);
        mutex_destroy(&ctx->mem_hash_lock);
        hl_mmu_ctx_fini(ctx);
free_va_range:
        for (i = 0 ; i < HL_VA_RANGE_TYPE_MAX ; i++)
                kfree(ctx->va_range[i]);

        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, host_huge_range_start,
                host_huge_range_end, dram_range_start, dram_range_end;
        u32 host_page_size, host_huge_page_size, dram_page_size;

        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)
                return 0;

        dram_range_start = prop->dmmu.start_addr;
        dram_range_end = prop->dmmu.end_addr;
        dram_page_size = prop->dram_page_size ?
                                prop->dram_page_size : prop->dmmu.page_size;
        host_range_start = prop->pmmu.start_addr;
        host_range_end = prop->pmmu.end_addr;
        host_page_size = prop->pmmu.page_size;
        host_huge_range_start = prop->pmmu_huge.start_addr;
        host_huge_range_end = prop->pmmu_huge.end_addr;
        host_huge_page_size = prop->pmmu_huge.page_size;

        return vm_ctx_init_with_ranges(ctx, host_range_start, host_range_end,
                        host_page_size, host_huge_range_start,
                        host_huge_range_end, host_huge_page_size,
                        dram_range_start, dram_range_end, dram_page_size);
}

/**
 * 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;
        struct hl_mem_in args;
        int i;

        if (!hdev->mmu_enable)
                return;

        hl_debugfs_remove_ctx_mem_hash(hdev, ctx);

        /*
         * Clearly something went wrong on hard reset so no point in printing
         * another side effect error
         */
        if (!hdev->hard_reset_pending && !hash_empty(ctx->mem_hash))
                dev_notice(hdev->dev,
                        "user released device without removing its memory mappings\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);
                args.unmap.device_virt_addr = hnode->vaddr;
                unmap_device_va(ctx, &args, true);
        }

        mutex_lock(&ctx->mmu_lock);

        /* invalidate the cache once after the unmapping loop */
        hdev->asic_funcs->mmu_invalidate_cache(hdev, true, VM_TYPE_USERPTR);
        hdev->asic_funcs->mmu_invalidate_cache(hdev, true, VM_TYPE_PHYS_PACK);

        mutex_unlock(&ctx->mmu_lock);

        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%px 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);

        va_range_fini(hdev, ctx->va_range[HL_VA_RANGE_TYPE_DRAM]);
        va_range_fini(hdev, ctx->va_range[HL_VA_RANGE_TYPE_HOST]);

        if (hdev->pmmu_huge_range)
                va_range_fini(hdev, ctx->va_range[HL_VA_RANGE_TYPE_HOST_HUGE]);

        mutex_destroy(&ctx->mem_hash_lock);
        hl_mmu_ctx_fini(ctx);

        /* In this case we need to clear the global accounting of DRAM usage
         * because the user notifies us on allocations. If the user is no more,
         * all DRAM is available
         */
        if (ctx->asid != HL_KERNEL_ASID_ID &&
                        !hdev->asic_prop.dram_supports_virtual_memory)
                atomic64_set(&hdev->dram_used_mem, 0);
}

/**
 * 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;

        if (is_power_of_2(prop->dram_page_size))
                vm->dram_pg_pool =
                        gen_pool_create(__ffs(prop->dram_page_size), -1);
        else
                vm->dram_pg_pool =
                        gen_pool_create(__ffs(DRAM_POOL_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;
}

/**
 * hl_hw_block_mem_init() - HW block memory initialization.
 * @ctx: pointer to the habanalabs context structure.
 *
 * This function initializes the HW block virtual mapped addresses list and
 * it's lock.
 */
void hl_hw_block_mem_init(struct hl_ctx *ctx)
{
        mutex_init(&ctx->hw_block_list_lock);
        INIT_LIST_HEAD(&ctx->hw_block_mem_list);
}

/**
 * hl_hw_block_mem_fini() - HW block memory teardown.
 * @ctx: pointer to the habanalabs context structure.
 *
 * This function clears the HW block virtual mapped addresses list and destroys
 * it's lock.
 */
void hl_hw_block_mem_fini(struct hl_ctx *ctx)
{
        struct hl_vm_hw_block_list_node *lnode, *tmp;

        if (!list_empty(&ctx->hw_block_mem_list))
                dev_crit(ctx->hdev->dev, "HW block mem list isn't empty\n");

        list_for_each_entry_safe(lnode, tmp, &ctx->hw_block_mem_list, node) {
                list_del(&lnode->node);
                kfree(lnode);
        }

        mutex_destroy(&ctx->hw_block_list_lock);
}