// SPDX-License-Identifier: GPL-2.0-only
/*
 * AMD Secure Encrypted Virtualization (SEV) interface
 *
 * Copyright (C) 2016,2019 Advanced Micro Devices, Inc.
 *
 * Author: Brijesh Singh <brijesh.singh@amd.com>
 */

#include <linux/bitfield.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/spinlock_types.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/hw_random.h>
#include <linux/ccp.h>
#include <linux/firmware.h>
#include <linux/panic_notifier.h>
#include <linux/gfp.h>
#include <linux/cpufeature.h>
#include <linux/fs.h>
#include <linux/fs_struct.h>
#include <linux/psp.h>
#include <linux/amd-iommu.h>
#include <linux/crash_dump.h>

#include <asm/smp.h>
#include <asm/cacheflush.h>
#include <asm/e820/types.h>
#include <asm/sev.h>
#include <asm/msr.h>

#include "psp-dev.h"
#include "sev-dev.h"

#define DEVICE_NAME             "sev"
#define SEV_FW_FILE             "amd/sev.fw"
#define SEV_FW_NAME_SIZE        64

/* Minimum firmware version required for the SEV-SNP support */
#define SNP_MIN_API_MAJOR       1
#define SNP_MIN_API_MINOR       51

/*
 * Maximum number of firmware-writable buffers that might be specified
 * in the parameters of a legacy SEV command buffer.
 */
#define CMD_BUF_FW_WRITABLE_MAX 2

/* Leave room in the descriptor array for an end-of-list indicator. */
#define CMD_BUF_DESC_MAX (CMD_BUF_FW_WRITABLE_MAX + 1)

static DEFINE_MUTEX(sev_cmd_mutex);
static struct sev_misc_dev *misc_dev;

static int psp_cmd_timeout = 100;
module_param(psp_cmd_timeout, int, 0644);
MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");

static int psp_probe_timeout = 5;
module_param(psp_probe_timeout, int, 0644);
MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");

static char *init_ex_path;
module_param(init_ex_path, charp, 0444);
MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX");

static bool psp_init_on_probe = true;
module_param(psp_init_on_probe, bool, 0444);
MODULE_PARM_DESC(psp_init_on_probe, "  if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it");

#if IS_ENABLED(CONFIG_PCI_TSM)
static bool sev_tio_enabled = true;
module_param_named(tio, sev_tio_enabled, bool, 0444);
MODULE_PARM_DESC(tio, "Enables TIO in SNP_INIT_EX");
#else
static const bool sev_tio_enabled = false;
#endif

MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */

static bool psp_dead;
static int psp_timeout;

enum snp_hv_fixed_pages_state {
        ALLOCATED,
        HV_FIXED,
};

struct snp_hv_fixed_pages_entry {
        struct list_head list;
        struct page *page;
        unsigned int order;
        bool free;
        enum snp_hv_fixed_pages_state page_state;
};

static LIST_HEAD(snp_hv_fixed_pages);

/* Trusted Memory Region (TMR):
 *   The TMR is a 1MB area that must be 1MB aligned.  Use the page allocator
 *   to allocate the memory, which will return aligned memory for the specified
 *   allocation order.
 *
 * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized.
 */
#define SEV_TMR_SIZE            (1024 * 1024)
#define SNP_TMR_SIZE            (2 * 1024 * 1024)

static void *sev_es_tmr;
static size_t sev_es_tmr_size = SEV_TMR_SIZE;

/* INIT_EX NV Storage:
 *   The NV Storage is a 32Kb area and must be 4Kb page aligned.  Use the page
 *   allocator to allocate the memory, which will return aligned memory for the
 *   specified allocation order.
 */
#define NV_LENGTH (32 * 1024)
static void *sev_init_ex_buffer;

static void __sev_firmware_shutdown(struct sev_device *sev, bool panic);

static int snp_shutdown_on_panic(struct notifier_block *nb,
                                 unsigned long reason, void *arg);

static struct notifier_block snp_panic_notifier = {
        .notifier_call = snp_shutdown_on_panic,
};

static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
{
        struct sev_device *sev = psp_master->sev_data;

        if (sev->api_major > maj)
                return true;

        if (sev->api_major == maj && sev->api_minor >= min)
                return true;

        return false;
}

static void sev_irq_handler(int irq, void *data, unsigned int status)
{
        struct sev_device *sev = data;
        int reg;

        /* Check if it is command completion: */
        if (!(status & SEV_CMD_COMPLETE))
                return;

        /* Check if it is SEV command completion: */
        reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
        if (FIELD_GET(PSP_CMDRESP_RESP, reg)) {
                sev->int_rcvd = 1;
                wake_up(&sev->int_queue);
        }
}

static int sev_wait_cmd_ioc(struct sev_device *sev,
                            unsigned int *reg, unsigned int timeout)
{
        int ret;

        /*
         * If invoked during panic handling, local interrupts are disabled,
         * so the PSP command completion interrupt can't be used. Poll for
         * PSP command completion instead.
         */
        if (irqs_disabled()) {
                unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10;

                /* Poll for SEV command completion: */
                while (timeout_usecs--) {
                        *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
                        if (*reg & PSP_CMDRESP_RESP)
                                return 0;

                        udelay(10);
                }
                return -ETIMEDOUT;
        }

        ret = wait_event_timeout(sev->int_queue,
                        sev->int_rcvd, timeout * HZ);
        if (!ret)
                return -ETIMEDOUT;

        *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);

        return 0;
}

static int sev_cmd_buffer_len(int cmd)
{
        switch (cmd) {
        case SEV_CMD_INIT:                      return sizeof(struct sev_data_init);
        case SEV_CMD_INIT_EX:                   return sizeof(struct sev_data_init_ex);
        case SEV_CMD_SNP_SHUTDOWN_EX:           return sizeof(struct sev_data_snp_shutdown_ex);
        case SEV_CMD_SNP_INIT_EX:               return sizeof(struct sev_data_snp_init_ex);
        case SEV_CMD_PLATFORM_STATUS:           return sizeof(struct sev_user_data_status);
        case SEV_CMD_PEK_CSR:                   return sizeof(struct sev_data_pek_csr);
        case SEV_CMD_PEK_CERT_IMPORT:           return sizeof(struct sev_data_pek_cert_import);
        case SEV_CMD_PDH_CERT_EXPORT:           return sizeof(struct sev_data_pdh_cert_export);
        case SEV_CMD_LAUNCH_START:              return sizeof(struct sev_data_launch_start);
        case SEV_CMD_LAUNCH_UPDATE_DATA:        return sizeof(struct sev_data_launch_update_data);
        case SEV_CMD_LAUNCH_UPDATE_VMSA:        return sizeof(struct sev_data_launch_update_vmsa);
        case SEV_CMD_LAUNCH_FINISH:             return sizeof(struct sev_data_launch_finish);
        case SEV_CMD_LAUNCH_MEASURE:            return sizeof(struct sev_data_launch_measure);
        case SEV_CMD_ACTIVATE:                  return sizeof(struct sev_data_activate);
        case SEV_CMD_DEACTIVATE:                return sizeof(struct sev_data_deactivate);
        case SEV_CMD_DECOMMISSION:              return sizeof(struct sev_data_decommission);
        case SEV_CMD_GUEST_STATUS:              return sizeof(struct sev_data_guest_status);
        case SEV_CMD_DBG_DECRYPT:               return sizeof(struct sev_data_dbg);
        case SEV_CMD_DBG_ENCRYPT:               return sizeof(struct sev_data_dbg);
        case SEV_CMD_SEND_START:                return sizeof(struct sev_data_send_start);
        case SEV_CMD_SEND_UPDATE_DATA:          return sizeof(struct sev_data_send_update_data);
        case SEV_CMD_SEND_UPDATE_VMSA:          return sizeof(struct sev_data_send_update_vmsa);
        case SEV_CMD_SEND_FINISH:               return sizeof(struct sev_data_send_finish);
        case SEV_CMD_RECEIVE_START:             return sizeof(struct sev_data_receive_start);
        case SEV_CMD_RECEIVE_FINISH:            return sizeof(struct sev_data_receive_finish);
        case SEV_CMD_RECEIVE_UPDATE_DATA:       return sizeof(struct sev_data_receive_update_data);
        case SEV_CMD_RECEIVE_UPDATE_VMSA:       return sizeof(struct sev_data_receive_update_vmsa);
        case SEV_CMD_LAUNCH_UPDATE_SECRET:      return sizeof(struct sev_data_launch_secret);
        case SEV_CMD_DOWNLOAD_FIRMWARE:         return sizeof(struct sev_data_download_firmware);
        case SEV_CMD_GET_ID:                    return sizeof(struct sev_data_get_id);
        case SEV_CMD_ATTESTATION_REPORT:        return sizeof(struct sev_data_attestation_report);
        case SEV_CMD_SEND_CANCEL:               return sizeof(struct sev_data_send_cancel);
        case SEV_CMD_SNP_GCTX_CREATE:           return sizeof(struct sev_data_snp_addr);
        case SEV_CMD_SNP_LAUNCH_START:          return sizeof(struct sev_data_snp_launch_start);
        case SEV_CMD_SNP_LAUNCH_UPDATE:         return sizeof(struct sev_data_snp_launch_update);
        case SEV_CMD_SNP_ACTIVATE:              return sizeof(struct sev_data_snp_activate);
        case SEV_CMD_SNP_DECOMMISSION:          return sizeof(struct sev_data_snp_addr);
        case SEV_CMD_SNP_PAGE_RECLAIM:          return sizeof(struct sev_data_snp_page_reclaim);
        case SEV_CMD_SNP_GUEST_STATUS:          return sizeof(struct sev_data_snp_guest_status);
        case SEV_CMD_SNP_LAUNCH_FINISH:         return sizeof(struct sev_data_snp_launch_finish);
        case SEV_CMD_SNP_DBG_DECRYPT:           return sizeof(struct sev_data_snp_dbg);
        case SEV_CMD_SNP_DBG_ENCRYPT:           return sizeof(struct sev_data_snp_dbg);
        case SEV_CMD_SNP_PAGE_UNSMASH:          return sizeof(struct sev_data_snp_page_unsmash);
        case SEV_CMD_SNP_PLATFORM_STATUS:       return sizeof(struct sev_data_snp_addr);
        case SEV_CMD_SNP_GUEST_REQUEST:         return sizeof(struct sev_data_snp_guest_request);
        case SEV_CMD_SNP_CONFIG:                return sizeof(struct sev_user_data_snp_config);
        case SEV_CMD_SNP_COMMIT:                return sizeof(struct sev_data_snp_commit);
        case SEV_CMD_SNP_FEATURE_INFO:          return sizeof(struct sev_data_snp_feature_info);
        case SEV_CMD_SNP_VLEK_LOAD:             return sizeof(struct sev_user_data_snp_vlek_load);
        default:                                return sev_tio_cmd_buffer_len(cmd);
        }

        return 0;
}

static struct file *open_file_as_root(const char *filename, int flags, umode_t mode)
{
        struct path root __free(path_put) = {};

        task_lock(&init_task);
        get_fs_root(init_task.fs, &root);
        task_unlock(&init_task);

        CLASS(prepare_creds, cred)();
        if (!cred)
                return ERR_PTR(-ENOMEM);

        cred->fsuid = GLOBAL_ROOT_UID;

        scoped_with_creds(cred)
                return file_open_root(&root, filename, flags, mode);
}

static int sev_read_init_ex_file(void)
{
        struct sev_device *sev = psp_master->sev_data;
        struct file *fp;
        ssize_t nread;

        lockdep_assert_held(&sev_cmd_mutex);

        if (!sev_init_ex_buffer)
                return -EOPNOTSUPP;

        fp = open_file_as_root(init_ex_path, O_RDONLY, 0);
        if (IS_ERR(fp)) {
                int ret = PTR_ERR(fp);

                if (ret == -ENOENT) {
                        dev_info(sev->dev,
                                "SEV: %s does not exist and will be created later.\n",
                                init_ex_path);
                        ret = 0;
                } else {
                        dev_err(sev->dev,
                                "SEV: could not open %s for read, error %d\n",
                                init_ex_path, ret);
                }
                return ret;
        }

        nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL);
        if (nread != NV_LENGTH) {
                dev_info(sev->dev,
                        "SEV: could not read %u bytes to non volatile memory area, ret %ld\n",
                        NV_LENGTH, nread);
        }

        dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread);
        filp_close(fp, NULL);

        return 0;
}

static int sev_write_init_ex_file(void)
{
        struct sev_device *sev = psp_master->sev_data;
        struct file *fp;
        loff_t offset = 0;
        ssize_t nwrite;

        lockdep_assert_held(&sev_cmd_mutex);

        if (!sev_init_ex_buffer)
                return 0;

        fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600);
        if (IS_ERR(fp)) {
                int ret = PTR_ERR(fp);

                dev_err(sev->dev,
                        "SEV: could not open file for write, error %d\n",
                        ret);
                return ret;
        }

        nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset);
        vfs_fsync(fp, 0);
        filp_close(fp, NULL);

        if (nwrite != NV_LENGTH) {
                dev_err(sev->dev,
                        "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n",
                        NV_LENGTH, nwrite);
                return -EIO;
        }

        dev_dbg(sev->dev, "SEV: write successful to NV file\n");

        return 0;
}

static int sev_write_init_ex_file_if_required(int cmd_id)
{
        lockdep_assert_held(&sev_cmd_mutex);

        if (!sev_init_ex_buffer)
                return 0;

        /*
         * Only a few platform commands modify the SPI/NV area, but none of the
         * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN,
         * PEK_CERT_IMPORT, and PDH_GEN do.
         */
        switch (cmd_id) {
        case SEV_CMD_FACTORY_RESET:
        case SEV_CMD_INIT_EX:
        case SEV_CMD_PDH_GEN:
        case SEV_CMD_PEK_CERT_IMPORT:
        case SEV_CMD_PEK_GEN:
                break;
        default:
                return 0;
        }

        return sev_write_init_ex_file();
}

int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked)
{
        int ret, err, i;

        paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE));

        for (i = 0; i < npages; i++, paddr += PAGE_SIZE) {
                struct sev_data_snp_page_reclaim data = {0};

                data.paddr = paddr;

                if (locked)
                        ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
                else
                        ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);

                if (ret)
                        goto cleanup;

                ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K);
                if (ret)
                        goto cleanup;
        }

        return 0;

cleanup:
        /*
         * If there was a failure reclaiming the page then it is no longer safe
         * to release it back to the system; leak it instead.
         */
        snp_leak_pages(__phys_to_pfn(paddr), npages - i);
        return ret;
}
EXPORT_SYMBOL_GPL(snp_reclaim_pages);

static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked)
{
        unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT;
        int rc, i;

        for (i = 0; i < npages; i++, pfn++) {
                rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true);
                if (rc)
                        goto cleanup;
        }

        return 0;

cleanup:
        /*
         * Try unrolling the firmware state changes by
         * reclaiming the pages which were already changed to the
         * firmware state.
         */
        snp_reclaim_pages(paddr, i, locked);

        return rc;
}

static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked)
{
        unsigned long npages = 1ul << order, paddr;
        struct sev_device *sev;
        struct page *page;

        if (!psp_master || !psp_master->sev_data)
                return NULL;

        page = alloc_pages(gfp_mask, order);
        if (!page)
                return NULL;

        /* If SEV-SNP is initialized then add the page in RMP table. */
        sev = psp_master->sev_data;
        if (!sev->snp_initialized)
                return page;

        paddr = __pa((unsigned long)page_address(page));
        if (rmp_mark_pages_firmware(paddr, npages, locked))
                return NULL;

        return page;
}

void *snp_alloc_firmware_page(gfp_t gfp_mask)
{
        struct page *page;

        page = __snp_alloc_firmware_pages(gfp_mask, 0, false);

        return page ? page_address(page) : NULL;
}
EXPORT_SYMBOL_GPL(snp_alloc_firmware_page);

static void __snp_free_firmware_pages(struct page *page, int order, bool locked)
{
        struct sev_device *sev = psp_master->sev_data;
        unsigned long paddr, npages = 1ul << order;

        if (!page)
                return;

        paddr = __pa((unsigned long)page_address(page));
        if (sev->snp_initialized &&
            snp_reclaim_pages(paddr, npages, locked))
                return;

        __free_pages(page, order);
}

void snp_free_firmware_page(void *addr)
{
        if (!addr)
                return;

        __snp_free_firmware_pages(virt_to_page(addr), 0, false);
}
EXPORT_SYMBOL_GPL(snp_free_firmware_page);

static void *sev_fw_alloc(unsigned long len)
{
        struct page *page;

        page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true);
        if (!page)
                return NULL;

        return page_address(page);
}

/**
 * struct cmd_buf_desc - descriptors for managing legacy SEV command address
 * parameters corresponding to buffers that may be written to by firmware.
 *
 * @paddr_ptr:  pointer to the address parameter in the command buffer which may
 *              need to be saved/restored depending on whether a bounce buffer
 *              is used. In the case of a bounce buffer, the command buffer
 *              needs to be updated with the address of the new bounce buffer
 *              snp_map_cmd_buf_desc() has allocated specifically for it. Must
 *              be NULL if this descriptor is only an end-of-list indicator.
 *
 * @paddr_orig: storage for the original address parameter, which can be used to
 *              restore the original value in @paddr_ptr in cases where it is
 *              replaced with the address of a bounce buffer.
 *
 * @len: length of buffer located at the address originally stored at @paddr_ptr
 *
 * @guest_owned: true if the address corresponds to guest-owned pages, in which
 *               case bounce buffers are not needed.
 */
struct cmd_buf_desc {
        u64 *paddr_ptr;
        u64 paddr_orig;
        u32 len;
        bool guest_owned;
};

/*
 * If a legacy SEV command parameter is a memory address, those pages in
 * turn need to be transitioned to/from firmware-owned before/after
 * executing the firmware command.
 *
 * Additionally, in cases where those pages are not guest-owned, a bounce
 * buffer is needed in place of the original memory address parameter.
 *
 * A set of descriptors are used to keep track of this handling, and
 * initialized here based on the specific commands being executed.
 */
static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf,
                                           struct cmd_buf_desc *desc_list)
{
        switch (cmd) {
        case SEV_CMD_PDH_CERT_EXPORT: {
                struct sev_data_pdh_cert_export *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->pdh_cert_address;
                desc_list[0].len = data->pdh_cert_len;
                desc_list[1].paddr_ptr = &data->cert_chain_address;
                desc_list[1].len = data->cert_chain_len;
                break;
        }
        case SEV_CMD_GET_ID: {
                struct sev_data_get_id *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->address;
                desc_list[0].len = data->len;
                break;
        }
        case SEV_CMD_PEK_CSR: {
                struct sev_data_pek_csr *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->address;
                desc_list[0].len = data->len;
                break;
        }
        case SEV_CMD_LAUNCH_UPDATE_DATA: {
                struct sev_data_launch_update_data *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->address;
                desc_list[0].len = data->len;
                desc_list[0].guest_owned = true;
                break;
        }
        case SEV_CMD_LAUNCH_UPDATE_VMSA: {
                struct sev_data_launch_update_vmsa *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->address;
                desc_list[0].len = data->len;
                desc_list[0].guest_owned = true;
                break;
        }
        case SEV_CMD_LAUNCH_MEASURE: {
                struct sev_data_launch_measure *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->address;
                desc_list[0].len = data->len;
                break;
        }
        case SEV_CMD_LAUNCH_UPDATE_SECRET: {
                struct sev_data_launch_secret *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->guest_address;
                desc_list[0].len = data->guest_len;
                desc_list[0].guest_owned = true;
                break;
        }
        case SEV_CMD_DBG_DECRYPT: {
                struct sev_data_dbg *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->dst_addr;
                desc_list[0].len = data->len;
                desc_list[0].guest_owned = true;
                break;
        }
        case SEV_CMD_DBG_ENCRYPT: {
                struct sev_data_dbg *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->dst_addr;
                desc_list[0].len = data->len;
                desc_list[0].guest_owned = true;
                break;
        }
        case SEV_CMD_ATTESTATION_REPORT: {
                struct sev_data_attestation_report *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->address;
                desc_list[0].len = data->len;
                break;
        }
        case SEV_CMD_SEND_START: {
                struct sev_data_send_start *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->session_address;
                desc_list[0].len = data->session_len;
                break;
        }
        case SEV_CMD_SEND_UPDATE_DATA: {
                struct sev_data_send_update_data *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->hdr_address;
                desc_list[0].len = data->hdr_len;
                desc_list[1].paddr_ptr = &data->trans_address;
                desc_list[1].len = data->trans_len;
                break;
        }
        case SEV_CMD_SEND_UPDATE_VMSA: {
                struct sev_data_send_update_vmsa *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->hdr_address;
                desc_list[0].len = data->hdr_len;
                desc_list[1].paddr_ptr = &data->trans_address;
                desc_list[1].len = data->trans_len;
                break;
        }
        case SEV_CMD_RECEIVE_UPDATE_DATA: {
                struct sev_data_receive_update_data *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->guest_address;
                desc_list[0].len = data->guest_len;
                desc_list[0].guest_owned = true;
                break;
        }
        case SEV_CMD_RECEIVE_UPDATE_VMSA: {
                struct sev_data_receive_update_vmsa *data = cmd_buf;

                desc_list[0].paddr_ptr = &data->guest_address;
                desc_list[0].len = data->guest_len;
                desc_list[0].guest_owned = true;
                break;
        }
        default:
                break;
        }
}

static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc)
{
        unsigned int npages;

        if (!desc->len)
                return 0;

        /* Allocate a bounce buffer if this isn't a guest owned page. */
        if (!desc->guest_owned) {
                struct page *page;

                page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len));
                if (!page) {
                        pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n");
                        return -ENOMEM;
                }

                desc->paddr_orig = *desc->paddr_ptr;
                *desc->paddr_ptr = __psp_pa(page_to_virt(page));
        }

        npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;

        /* Transition the buffer to firmware-owned. */
        if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) {
                pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n");
                return -EFAULT;
        }

        return 0;
}

static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc)
{
        unsigned int npages;

        if (!desc->len)
                return 0;

        npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT;

        /* Transition the buffers back to hypervisor-owned. */
        if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) {
                pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n");
                return -EFAULT;
        }

        /* Copy data from bounce buffer and then free it. */
        if (!desc->guest_owned) {
                void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr));
                void *dst_buf = __va(__sme_clr(desc->paddr_orig));

                memcpy(dst_buf, bounce_buf, desc->len);
                __free_pages(virt_to_page(bounce_buf), get_order(desc->len));

                /* Restore the original address in the command buffer. */
                *desc->paddr_ptr = desc->paddr_orig;
        }

        return 0;
}

static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
{
        int i;

        snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list);

        for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
                struct cmd_buf_desc *desc = &desc_list[i];

                if (!desc->paddr_ptr)
                        break;

                if (snp_map_cmd_buf_desc(desc))
                        goto err_unmap;
        }

        return 0;

err_unmap:
        for (i--; i >= 0; i--)
                snp_unmap_cmd_buf_desc(&desc_list[i]);

        return -EFAULT;
}

static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list)
{
        int i, ret = 0;

        for (i = 0; i < CMD_BUF_DESC_MAX; i++) {
                struct cmd_buf_desc *desc = &desc_list[i];

                if (!desc->paddr_ptr)
                        break;

                if (snp_unmap_cmd_buf_desc(&desc_list[i]))
                        ret = -EFAULT;
        }

        return ret;
}

static bool sev_cmd_buf_writable(int cmd)
{
        switch (cmd) {
        case SEV_CMD_PLATFORM_STATUS:
        case SEV_CMD_GUEST_STATUS:
        case SEV_CMD_LAUNCH_START:
        case SEV_CMD_RECEIVE_START:
        case SEV_CMD_LAUNCH_MEASURE:
        case SEV_CMD_SEND_START:
        case SEV_CMD_SEND_UPDATE_DATA:
        case SEV_CMD_SEND_UPDATE_VMSA:
        case SEV_CMD_PEK_CSR:
        case SEV_CMD_PDH_CERT_EXPORT:
        case SEV_CMD_GET_ID:
        case SEV_CMD_ATTESTATION_REPORT:
                return true;
        default:
                return false;
        }
}

/* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */
static bool snp_legacy_handling_needed(int cmd)
{
        struct sev_device *sev = psp_master->sev_data;

        return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized;
}

static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list)
{
        if (!snp_legacy_handling_needed(cmd))
                return 0;

        if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list))
                return -EFAULT;

        /*
         * Before command execution, the command buffer needs to be put into
         * the firmware-owned state.
         */
        if (sev_cmd_buf_writable(cmd)) {
                if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true))
                        return -EFAULT;
        }

        return 0;
}

static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf)
{
        if (!snp_legacy_handling_needed(cmd))
                return 0;

        /*
         * After command completion, the command buffer needs to be put back
         * into the hypervisor-owned state.
         */
        if (sev_cmd_buf_writable(cmd))
                if (snp_reclaim_pages(__pa(cmd_buf), 1, true))
                        return -EFAULT;

        return 0;
}

int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
{
        struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0};
        struct psp_device *psp = psp_master;
        struct sev_device *sev;
        unsigned int cmdbuff_hi, cmdbuff_lo;
        unsigned int phys_lsb, phys_msb;
        unsigned int reg;
        void *cmd_buf;
        int buf_len;
        int ret = 0;

        if (!psp || !psp->sev_data)
                return -ENODEV;

        if (psp_dead)
                return -EBUSY;

        sev = psp->sev_data;

        buf_len = sev_cmd_buffer_len(cmd);
        if (WARN_ON_ONCE(!data != !buf_len))
                return -EINVAL;

        /*
         * Copy the incoming data to driver's scratch buffer as __pa() will not
         * work for some memory, e.g. vmalloc'd addresses, and @data may not be
         * physically contiguous.
         */
        if (data) {
                /*
                 * Commands are generally issued one at a time and require the
                 * sev_cmd_mutex, but there could be recursive firmware requests
                 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while
                 * preparing buffers for another command. This is the only known
                 * case of nesting in the current code, so exactly one
                 * additional command buffer is available for that purpose.
                 */
                if (!sev->cmd_buf_active) {
                        cmd_buf = sev->cmd_buf;
                        sev->cmd_buf_active = true;
                } else if (!sev->cmd_buf_backup_active) {
                        cmd_buf = sev->cmd_buf_backup;
                        sev->cmd_buf_backup_active = true;
                } else {
                        dev_err(sev->dev,
                                "SEV: too many firmware commands in progress, no command buffers available.\n");
                        return -EBUSY;
                }

                memcpy(cmd_buf, data, buf_len);

                /*
                 * The behavior of the SEV-legacy commands is altered when the
                 * SNP firmware is in the INIT state.
                 */
                ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list);
                if (ret) {
                        dev_err(sev->dev,
                                "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n",
                                cmd, ret);
                        return ret;
                }
        } else {
                cmd_buf = sev->cmd_buf;
        }

        /* Get the physical address of the command buffer */
        phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0;
        phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0;

        dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
                cmd, phys_msb, phys_lsb, psp_timeout);

        print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
                             buf_len, false);

        iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
        iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);

        sev->int_rcvd = 0;

        reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd);

        /*
         * If invoked during panic handling, local interrupts are disabled so
         * the PSP command completion interrupt can't be used.
         * sev_wait_cmd_ioc() already checks for interrupts disabled and
         * polls for PSP command completion.  Ensure we do not request an
         * interrupt from the PSP if irqs disabled.
         */
        if (!irqs_disabled())
                reg |= SEV_CMDRESP_IOC;

        iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);

        /* wait for command completion */
        ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
        if (ret) {
                if (psp_ret)
                        *psp_ret = 0;

                dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
                psp_dead = true;

                return ret;
        }

        psp_timeout = psp_cmd_timeout;

        if (psp_ret)
                *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg);

        if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
                dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n",
                        cmd, FIELD_GET(PSP_CMDRESP_STS, reg));

                /*
                 * PSP firmware may report additional error information in the
                 * command buffer registers on error. Print contents of command
                 * buffer registers if they changed.
                 */
                cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
                cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
                if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) {
                        dev_dbg(sev->dev, "Additional error information reported in cmdbuff:");
                        dev_dbg(sev->dev, "  cmdbuff hi: %#010x\n", cmdbuff_hi);
                        dev_dbg(sev->dev, "  cmdbuff lo: %#010x\n", cmdbuff_lo);
                }
                ret = -EIO;
        } else {
                ret = sev_write_init_ex_file_if_required(cmd);
        }

        /*
         * Copy potential output from the PSP back to data.  Do this even on
         * failure in case the caller wants to glean something from the error.
         */
        if (data) {
                int ret_reclaim;
                /*
                 * Restore the page state after the command completes.
                 */
                ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf);
                if (ret_reclaim) {
                        dev_err(sev->dev,
                                "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n",
                                cmd, ret_reclaim);
                        return ret_reclaim;
                }

                memcpy(data, cmd_buf, buf_len);

                if (sev->cmd_buf_backup_active)
                        sev->cmd_buf_backup_active = false;
                else
                        sev->cmd_buf_active = false;

                if (snp_unmap_cmd_buf_desc_list(desc_list))
                        return -EFAULT;
        }

        print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
                             buf_len, false);

        return ret;
}

int sev_do_cmd(int cmd, void *data, int *psp_ret)
{
        int rc;

        mutex_lock(&sev_cmd_mutex);
        rc = __sev_do_cmd_locked(cmd, data, psp_ret);
        mutex_unlock(&sev_cmd_mutex);

        return rc;
}
EXPORT_SYMBOL_GPL(sev_do_cmd);

static int __sev_init_locked(int *error)
{
        struct sev_data_init data;

        memset(&data, 0, sizeof(data));
        if (sev_es_tmr) {
                /*
                 * Do not include the encryption mask on the physical
                 * address of the TMR (firmware should clear it anyway).
                 */
                data.tmr_address = __pa(sev_es_tmr);

                data.flags |= SEV_INIT_FLAGS_SEV_ES;
                data.tmr_len = sev_es_tmr_size;
        }

        return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
}

static int __sev_init_ex_locked(int *error)
{
        struct sev_data_init_ex data;

        memset(&data, 0, sizeof(data));
        data.length = sizeof(data);
        data.nv_address = __psp_pa(sev_init_ex_buffer);
        data.nv_len = NV_LENGTH;

        if (sev_es_tmr) {
                /*
                 * Do not include the encryption mask on the physical
                 * address of the TMR (firmware should clear it anyway).
                 */
                data.tmr_address = __pa(sev_es_tmr);

                data.flags |= SEV_INIT_FLAGS_SEV_ES;
                data.tmr_len = sev_es_tmr_size;
        }

        return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
}

static inline int __sev_do_init_locked(int *psp_ret)
{
        if (sev_init_ex_buffer)
                return __sev_init_ex_locked(psp_ret);
        else
                return __sev_init_locked(psp_ret);
}

static void snp_set_hsave_pa(void *arg)
{
        wrmsrq(MSR_VM_HSAVE_PA, 0);
}

/* Hypervisor Fixed pages API interface */
static void snp_hv_fixed_pages_state_update(struct sev_device *sev,
                                            enum snp_hv_fixed_pages_state page_state)
{
        struct snp_hv_fixed_pages_entry *entry;

        /* List is protected by sev_cmd_mutex */
        lockdep_assert_held(&sev_cmd_mutex);

        if (list_empty(&snp_hv_fixed_pages))
                return;

        list_for_each_entry(entry, &snp_hv_fixed_pages, list)
                entry->page_state = page_state;
}

/*
 * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole
 * 2MB pages are marked as HV_FIXED.
 */
struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages)
{
        struct psp_device *psp_master = psp_get_master_device();
        struct snp_hv_fixed_pages_entry *entry;
        unsigned int order;
        struct page *page;

        if (!psp_master)
                return NULL;

        order = get_order(PMD_SIZE * num_2mb_pages);

        /*
         * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
         * also needs to be protected using the same mutex.
         */
        guard(mutex)(&sev_cmd_mutex);

        /*
         * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed
         * page state, fail if SNP is already initialized.
         */
        if (psp_master->sev_data &&
            ((struct sev_device *)psp_master->sev_data)->snp_initialized)
                return NULL;

        /* Re-use freed pages that match the request */
        list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
                /* Hypervisor fixed page allocator implements exact fit policy */
                if (entry->order == order && entry->free) {
                        entry->free = false;
                        memset(page_address(entry->page), 0,
                               (1 << entry->order) * PAGE_SIZE);
                        return entry->page;
                }
        }

        page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
        if (!page)
                return NULL;

        entry = kzalloc_obj(*entry);
        if (!entry) {
                __free_pages(page, order);
                return NULL;
        }

        entry->page = page;
        entry->order = order;
        list_add_tail(&entry->list, &snp_hv_fixed_pages);

        return page;
}

void snp_free_hv_fixed_pages(struct page *page)
{
        struct psp_device *psp_master = psp_get_master_device();
        struct snp_hv_fixed_pages_entry *entry, *nentry;

        if (!psp_master)
                return;

        /*
         * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list
         * also needs to be protected using the same mutex.
         */
        guard(mutex)(&sev_cmd_mutex);

        list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) {
                if (entry->page != page)
                        continue;

                /*
                 * HV_FIXED page state cannot be changed until reboot
                 * and they cannot be used by an SNP guest, so they cannot
                 * be returned back to the page allocator.
                 * Mark the pages as free internally to allow possible re-use.
                 */
                if (entry->page_state == HV_FIXED) {
                        entry->free = true;
                } else {
                        __free_pages(page, entry->order);
                        list_del(&entry->list);
                        kfree(entry);
                }
                return;
        }
}

static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list)
{
        struct snp_hv_fixed_pages_entry *entry;
        struct sev_data_range *range;
        int num_elements;

        lockdep_assert_held(&sev_cmd_mutex);

        if (list_empty(&snp_hv_fixed_pages))
                return;

        num_elements = list_count_nodes(&snp_hv_fixed_pages) +
                       range_list->num_elements;

        /*
         * Ensure the list of HV_FIXED pages that will be passed to firmware
         * do not exceed the page-sized argument buffer.
         */
        if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) {
                dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n");
                return;
        }

        range = &range_list->ranges[range_list->num_elements];
        list_for_each_entry(entry, &snp_hv_fixed_pages, list) {
                range->base = page_to_pfn(entry->page) << PAGE_SHIFT;
                range->page_count = 1 << entry->order;
                range++;
        }
        range_list->num_elements = num_elements;
}

static void snp_leak_hv_fixed_pages(void)
{
        struct snp_hv_fixed_pages_entry *entry;

        /* List is protected by sev_cmd_mutex */
        lockdep_assert_held(&sev_cmd_mutex);

        if (list_empty(&snp_hv_fixed_pages))
                return;

        list_for_each_entry(entry, &snp_hv_fixed_pages, list)
                if (entry->page_state == HV_FIXED)
                        __snp_leak_pages(page_to_pfn(entry->page),
                                         1 << entry->order, false);
}

bool sev_is_snp_ciphertext_hiding_supported(void)
{
        struct psp_device *psp = psp_master;
        struct sev_device *sev;

        if (!psp || !psp->sev_data)
                return false;

        sev = psp->sev_data;

        /*
         * Feature information indicates if CipherTextHiding feature is
         * supported by the SEV firmware and additionally platform status
         * indicates if CipherTextHiding feature is enabled in the
         * Platform BIOS.
         */
        return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) &&
                 sev->snp_plat_status.ciphertext_hiding_cap);
}
EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported);

static int snp_get_platform_data(struct sev_device *sev, int *error)
{
        struct sev_data_snp_feature_info snp_feat_info;
        struct snp_feature_info *feat_info;
        struct sev_data_snp_addr buf;
        struct page *page;
        int rc;

        /*
         * This function is expected to be called before SNP is
         * initialized.
         */
        if (sev->snp_initialized)
                return -EINVAL;

        buf.address = __psp_pa(&sev->snp_plat_status);
        rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error);
        if (rc) {
                dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n",
                        rc, *error);
                return rc;
        }

        sev->api_major = sev->snp_plat_status.api_major;
        sev->api_minor = sev->snp_plat_status.api_minor;
        sev->build = sev->snp_plat_status.build_id;

        /*
         * Do feature discovery of the currently loaded firmware,
         * and cache feature information from CPUID 0x8000_0024,
         * sub-function 0.
         */
        if (!sev->snp_plat_status.feature_info)
                return 0;

        /*
         * Use dynamically allocated structure for the SNP_FEATURE_INFO
         * command to ensure structure is 8-byte aligned, and does not
         * cross a page boundary.
         */
        page = alloc_page(GFP_KERNEL);
        if (!page)
                return -ENOMEM;

        feat_info = page_address(page);
        snp_feat_info.length = sizeof(snp_feat_info);
        snp_feat_info.ecx_in = 0;
        snp_feat_info.feature_info_paddr = __psp_pa(feat_info);

        rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error);
        if (!rc)
                sev->snp_feat_info_0 = *feat_info;
        else
                dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n",
                        rc, *error);

        __free_page(page);

        return rc;
}

static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
{
        struct sev_data_range_list *range_list = arg;
        struct sev_data_range *range = &range_list->ranges[range_list->num_elements];
        size_t size;

        /*
         * Ensure the list of HV_FIXED pages that will be passed to firmware
         * do not exceed the page-sized argument buffer.
         */
        if ((range_list->num_elements * sizeof(struct sev_data_range) +
             sizeof(struct sev_data_range_list)) > PAGE_SIZE)
                return -E2BIG;

        switch (rs->desc) {
        case E820_TYPE_RESERVED:
        case E820_TYPE_PMEM:
        case E820_TYPE_ACPI:
                range->base = rs->start & PAGE_MASK;
                size = PAGE_ALIGN((rs->end + 1) - rs->start);
                range->page_count = size >> PAGE_SHIFT;
                range_list->num_elements++;
                break;
        default:
                break;
        }

        return 0;
}

static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
{
        struct sev_data_range_list *snp_range_list __free(kfree) = NULL;
        struct psp_device *psp = psp_master;
        struct sev_data_snp_init_ex data;
        struct sev_device *sev;
        void *arg = &data;
        int cmd, rc = 0;

        if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
                return -ENODEV;

        sev = psp->sev_data;

        if (sev->snp_initialized)
                return 0;

        if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) {
                dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n",
                        SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR);
                return -EOPNOTSUPP;
        }

        /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */
        on_each_cpu(snp_set_hsave_pa, NULL, 1);

        /*
         * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list
         * of system physical address ranges to convert into HV-fixed page
         * states during the RMP initialization.  For instance, the memory that
         * UEFI reserves should be included in the that list. This allows system
         * components that occasionally write to memory (e.g. logging to UEFI
         * reserved regions) to not fail due to RMP initialization and SNP
         * enablement.
         *
         */
        if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) {
                bool tio_supp = !!(sev->snp_feat_info_0.ebx & SNP_SEV_TIO_SUPPORTED);

                /*
                 * Firmware checks that the pages containing the ranges enumerated
                 * in the RANGES structure are either in the default page state or in the
                 * firmware page state.
                 */
                snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL);
                if (!snp_range_list) {
                        dev_err(sev->dev,
                                "SEV: SNP_INIT_EX range list memory allocation failed\n");
                        return -ENOMEM;
                }

                /*
                 * Retrieve all reserved memory regions from the e820 memory map
                 * to be setup as HV-fixed pages.
                 */
                rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0,
                                         snp_range_list, snp_filter_reserved_mem_regions);
                if (rc) {
                        dev_err(sev->dev,
                                "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc);
                        return rc;
                }

                /*
                 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the
                 * HV_Fixed page list.
                 */
                snp_add_hv_fixed_pages(sev, snp_range_list);

                memset(&data, 0, sizeof(data));

                if (max_snp_asid) {
                        data.ciphertext_hiding_en = 1;
                        data.max_snp_asid = max_snp_asid;
                }

                data.init_rmp = 1;
                data.list_paddr_en = 1;
                data.list_paddr = __psp_pa(snp_range_list);

                data.tio_en = tio_supp && sev_tio_enabled && amd_iommu_sev_tio_supported();

                /*
                 * When psp_init_on_probe is disabled, the userspace calling
                 * SEV ioctl can inadvertently shut down SNP and SEV-TIO causing
                 * unexpected state loss.
                 */
                if (data.tio_en && !psp_init_on_probe)
                        dev_warn(sev->dev, "SEV-TIO as incompatible with psp_init_on_probe=0\n");

                cmd = SEV_CMD_SNP_INIT_EX;
        } else {
                cmd = SEV_CMD_SNP_INIT;
                arg = NULL;
        }

        /*
         * The following sequence must be issued before launching the first SNP
         * guest to ensure all dirty cache lines are flushed, including from
         * updates to the RMP table itself via the RMPUPDATE instruction:
         *
         * - WBINVD on all running CPUs
         * - SEV_CMD_SNP_INIT[_EX] firmware command
         * - WBINVD on all running CPUs
         * - SEV_CMD_SNP_DF_FLUSH firmware command
         */
        wbinvd_on_all_cpus();

        rc = __sev_do_cmd_locked(cmd, arg, error);
        if (rc) {
                dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n",
                        cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT",
                        rc, *error);
                return rc;
        }

        /* Prepare for first SNP guest launch after INIT. */
        wbinvd_on_all_cpus();
        rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error);
        if (rc) {
                dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n",
                        rc, *error);
                return rc;
        }

        snp_hv_fixed_pages_state_update(sev, HV_FIXED);
        sev->snp_initialized = true;
        dev_dbg(sev->dev, "SEV-SNP firmware initialized, SEV-TIO is %s\n",
                data.tio_en ? "enabled" : "disabled");

        dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
                 sev->api_minor, sev->build);

        atomic_notifier_chain_register(&panic_notifier_list,
                                       &snp_panic_notifier);

        if (data.tio_en) {
                /*
                 * This executes with the sev_cmd_mutex held so down the stack
                 * snp_reclaim_pages(locked=false) might be needed (which is extremely
                 * unlikely) but will cause a deadlock.
                 * Instead of exporting __snp_alloc_firmware_pages(), allocate a page
                 * for this one call here.
                 */
                void *tio_status = page_address(__snp_alloc_firmware_pages(
                        GFP_KERNEL_ACCOUNT | __GFP_ZERO, 0, true));

                if (tio_status) {
                        sev_tsm_init_locked(sev, tio_status);
                        __snp_free_firmware_pages(virt_to_page(tio_status), 0, true);
                }
        }

        sev_es_tmr_size = SNP_TMR_SIZE;

        return 0;
}

static void __sev_platform_init_handle_tmr(struct sev_device *sev)
{
        if (sev_es_tmr)
                return;

        /* Obtain the TMR memory area for SEV-ES use */
        sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
        if (sev_es_tmr) {
                /* Must flush the cache before giving it to the firmware */
                if (!sev->snp_initialized)
                        clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
        } else {
                        dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n");
        }
}

/*
 * If an init_ex_path is provided allocate a buffer for the file and
 * read in the contents. Additionally, if SNP is initialized, convert
 * the buffer pages to firmware pages.
 */
static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev)
{
        struct page *page;
        int rc;

        if (!init_ex_path)
                return 0;

        if (sev_init_ex_buffer)
                return 0;

        page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH));
        if (!page) {
                dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n");
                return -ENOMEM;
        }

        sev_init_ex_buffer = page_address(page);

        rc = sev_read_init_ex_file();
        if (rc)
                return rc;

        /* If SEV-SNP is initialized, transition to firmware page. */
        if (sev->snp_initialized) {
                unsigned long npages;

                npages = 1UL << get_order(NV_LENGTH);
                if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) {
                        dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n");
                        return -ENOMEM;
                }
        }

        return 0;
}

static int __sev_platform_init_locked(int *error)
{
        int rc, psp_ret, dfflush_error;
        struct sev_device *sev;

        psp_ret = dfflush_error = SEV_RET_NO_FW_CALL;

        if (!psp_master || !psp_master->sev_data)
                return -ENODEV;

        sev = psp_master->sev_data;

        if (sev->sev_plat_status.state == SEV_STATE_INIT)
                return 0;

        __sev_platform_init_handle_tmr(sev);

        rc = __sev_platform_init_handle_init_ex_path(sev);
        if (rc)
                return rc;

        rc = __sev_do_init_locked(&psp_ret);
        if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
                /*
                 * Initialization command returned an integrity check failure
                 * status code, meaning that firmware load and validation of SEV
                 * related persistent data has failed. Retrying the
                 * initialization function should succeed by replacing the state
                 * with a reset state.
                 */
                dev_err(sev->dev,
"SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state.");
                rc = __sev_do_init_locked(&psp_ret);
        }

        if (error)
                *error = psp_ret;

        if (rc) {
                dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n",
                        sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc);
                return rc;
        }

        sev->sev_plat_status.state = SEV_STATE_INIT;

        /* Prepare for first SEV guest launch after INIT */
        wbinvd_on_all_cpus();
        rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error);
        if (rc) {
                dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n",
                        dfflush_error, rc);
                return rc;
        }

        dev_dbg(sev->dev, "SEV firmware initialized\n");

        dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
                 sev->api_minor, sev->build);

        return 0;
}

static int _sev_platform_init_locked(struct sev_platform_init_args *args)
{
        struct sev_device *sev;
        int rc;

        if (!psp_master || !psp_master->sev_data)
                return -ENODEV;

        /*
         * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP
         * may already be initialized in the previous kernel. Since no
         * SNP/SEV guests are run under a kdump kernel, there is no
         * need to initialize SNP or SEV during kdump boot.
         */
        if (is_kdump_kernel())
                return 0;

        sev = psp_master->sev_data;

        if (sev->sev_plat_status.state == SEV_STATE_INIT)
                return 0;

        rc = __sev_snp_init_locked(&args->error, args->max_snp_asid);
        if (rc && rc != -ENODEV)
                return rc;

        /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */
        if (args->probe && !psp_init_on_probe)
                return 0;

        return __sev_platform_init_locked(&args->error);
}

int sev_platform_init(struct sev_platform_init_args *args)
{
        int rc;

        mutex_lock(&sev_cmd_mutex);
        rc = _sev_platform_init_locked(args);
        mutex_unlock(&sev_cmd_mutex);

        return rc;
}
EXPORT_SYMBOL_GPL(sev_platform_init);

static int __sev_platform_shutdown_locked(int *error)
{
        struct psp_device *psp = psp_master;
        struct sev_device *sev;
        int ret;

        if (!psp || !psp->sev_data)
                return 0;

        sev = psp->sev_data;

        if (sev->sev_plat_status.state == SEV_STATE_UNINIT)
                return 0;

        ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
        if (ret) {
                dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n",
                        *error, ret);
                return ret;
        }

        sev->sev_plat_status.state = SEV_STATE_UNINIT;
        dev_dbg(sev->dev, "SEV firmware shutdown\n");

        return ret;
}

static int sev_get_platform_state(int *state, int *error)
{
        struct sev_user_data_status data;
        int rc;

        rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
        if (rc)
                return rc;

        *state = data.state;
        return rc;
}

static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
{
        struct sev_platform_init_args init_args = {0};
        int rc;

        rc = _sev_platform_init_locked(&init_args);
        if (rc) {
                argp->error = SEV_RET_INVALID_PLATFORM_STATE;
                return rc;
        }

        *shutdown_required = true;

        return 0;
}

static int snp_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required)
{
        int error, rc;

        rc = __sev_snp_init_locked(&error, 0);
        if (rc) {
                argp->error = SEV_RET_INVALID_PLATFORM_STATE;
                return rc;
        }

        *shutdown_required = true;

        return 0;
}

static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
{
        int state, rc;

        if (!writable)
                return -EPERM;

        /*
         * The SEV spec requires that FACTORY_RESET must be issued in
         * UNINIT state. Before we go further lets check if any guest is
         * active.
         *
         * If FW is in WORKING state then deny the request otherwise issue
         * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
         *
         */
        rc = sev_get_platform_state(&state, &argp->error);
        if (rc)
                return rc;

        if (state == SEV_STATE_WORKING)
                return -EBUSY;

        if (state == SEV_STATE_INIT) {
                rc = __sev_platform_shutdown_locked(&argp->error);
                if (rc)
                        return rc;
        }

        return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
}

static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
{
        struct sev_user_data_status data;
        int ret;

        memset(&data, 0, sizeof(data));

        ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
        if (ret)
                return ret;

        if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
                ret = -EFAULT;

        return ret;
}

static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
{
        struct sev_device *sev = psp_master->sev_data;
        bool shutdown_required = false;
        int rc;

        if (!writable)
                return -EPERM;

        if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
                rc = sev_move_to_init_state(argp, &shutdown_required);
                if (rc)
                        return rc;
        }

        rc = __sev_do_cmd_locked(cmd, NULL, &argp->error);

        if (shutdown_required)
                __sev_firmware_shutdown(sev, false);

        return rc;
}

static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_user_data_pek_csr input;
        bool shutdown_required = false;
        struct sev_data_pek_csr data;
        void __user *input_address;
        void *blob = NULL;
        int ret;

        if (!writable)
                return -EPERM;

        if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
                return -EFAULT;

        memset(&data, 0, sizeof(data));

        /* userspace wants to query CSR length */
        if (!input.address || !input.length)
                goto cmd;

        /* allocate a physically contiguous buffer to store the CSR blob */
        input_address = (void __user *)input.address;
        if (input.length > SEV_FW_BLOB_MAX_SIZE)
                return -EFAULT;

        blob = kzalloc(input.length, GFP_KERNEL);
        if (!blob)
                return -ENOMEM;

        data.address = __psp_pa(blob);
        data.len = input.length;

cmd:
        if (sev->sev_plat_status.state == SEV_STATE_UNINIT) {
                ret = sev_move_to_init_state(argp, &shutdown_required);
                if (ret)
                        goto e_free_blob;
        }

        ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);

         /* If we query the CSR length, FW responded with expected data. */
        input.length = data.len;

        if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
                ret = -EFAULT;
                goto e_free_blob;
        }

        if (blob) {
                if (copy_to_user(input_address, blob, input.length))
                        ret = -EFAULT;
        }

e_free_blob:
        if (shutdown_required)
                __sev_firmware_shutdown(sev, false);

        kfree(blob);
        return ret;
}

void *psp_copy_user_blob(u64 uaddr, u32 len)
{
        if (!uaddr || !len)
                return ERR_PTR(-EINVAL);

        /* verify that blob length does not exceed our limit */
        if (len > SEV_FW_BLOB_MAX_SIZE)
                return ERR_PTR(-EINVAL);

        return memdup_user((void __user *)uaddr, len);
}
EXPORT_SYMBOL_GPL(psp_copy_user_blob);

static int sev_get_api_version(void)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_user_data_status status;
        int error = 0, ret;

        /*
         * Cache SNP platform status and SNP feature information
         * if SNP is available.
         */
        if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) {
                ret = snp_get_platform_data(sev, &error);
                if (ret)
                        return 1;
        }

        ret = sev_platform_status(&status, &error);
        if (ret) {
                dev_err(sev->dev,
                        "SEV: failed to get status. Error: %#x\n", error);
                return 1;
        }

        /* Cache SEV platform status */
        sev->sev_plat_status = status;

        sev->api_major = status.api_major;
        sev->api_minor = status.api_minor;
        sev->build = status.build;

        return 0;
}

static int sev_get_firmware(struct device *dev,
                            const struct firmware **firmware)
{
        char fw_name_specific[SEV_FW_NAME_SIZE];
        char fw_name_subset[SEV_FW_NAME_SIZE];

        snprintf(fw_name_specific, sizeof(fw_name_specific),
                 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
                 boot_cpu_data.x86, boot_cpu_data.x86_model);

        snprintf(fw_name_subset, sizeof(fw_name_subset),
                 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
                 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);

        /* Check for SEV FW for a particular model.
         * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
         *
         * or
         *
         * Check for SEV FW common to a subset of models.
         * Ex. amd_sev_fam17h_model0xh.sbin for
         *     Family 17h Model 00h -- Family 17h Model 0Fh
         *
         * or
         *
         * Fall-back to using generic name: sev.fw
         */
        if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
            (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
            (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
                return 0;

        return -ENOENT;
}

/* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
static int sev_update_firmware(struct device *dev)
{
        struct sev_data_download_firmware *data;
        const struct firmware *firmware;
        int ret, error, order;
        struct page *p;
        u64 data_size;

        if (!sev_version_greater_or_equal(0, 15)) {
                dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
                return -1;
        }

        if (sev_get_firmware(dev, &firmware) == -ENOENT) {
                dev_dbg(dev, "No SEV firmware file present\n");
                return -1;
        }

        /*
         * SEV FW expects the physical address given to it to be 32
         * byte aligned. Memory allocated has structure placed at the
         * beginning followed by the firmware being passed to the SEV
         * FW. Allocate enough memory for data structure + alignment
         * padding + SEV FW.
         */
        data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);

        order = get_order(firmware->size + data_size);
        p = alloc_pages(GFP_KERNEL, order);
        if (!p) {
                ret = -1;
                goto fw_err;
        }

        /*
         * Copy firmware data to a kernel allocated contiguous
         * memory region.
         */
        data = page_address(p);
        memcpy(page_address(p) + data_size, firmware->data, firmware->size);

        data->address = __psp_pa(page_address(p) + data_size);
        data->len = firmware->size;

        ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);

        /*
         * A quirk for fixing the committed TCB version, when upgrading from
         * earlier firmware version than 1.50.
         */
        if (!ret && !sev_version_greater_or_equal(1, 50))
                ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);

        if (ret)
                dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);

        __free_pages(p, order);

fw_err:
        release_firmware(firmware);

        return ret;
}

static int __sev_snp_shutdown_locked(int *error, bool panic)
{
        struct psp_device *psp = psp_master;
        struct sev_device *sev;
        struct sev_data_snp_shutdown_ex data;
        int ret;

        if (!psp || !psp->sev_data)
                return 0;

        sev = psp->sev_data;

        if (!sev->snp_initialized)
                return 0;

        memset(&data, 0, sizeof(data));
        data.len = sizeof(data);
        data.iommu_snp_shutdown = 1;

        /*
         * If invoked during panic handling, local interrupts are disabled
         * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called.
         * In that case, a wbinvd() is done on remote CPUs via the NMI
         * callback, so only a local wbinvd() is needed here.
         */
        if (!panic)
                wbinvd_on_all_cpus();
        else
                wbinvd();

        ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error);
        /* SHUTDOWN may require DF_FLUSH */
        if (*error == SEV_RET_DFFLUSH_REQUIRED) {
                int dfflush_error = SEV_RET_NO_FW_CALL;

                ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error);
                if (ret) {
                        dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n",
                                ret, dfflush_error);
                        return ret;
                }
                /* reissue the shutdown command */
                ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data,
                                          error);
        }
        if (ret) {
                dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n",
                        ret, *error);
                return ret;
        }

        /*
         * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP
         * enforcement by the IOMMU and also transitions all pages
         * associated with the IOMMU to the Reclaim state.
         * Firmware was transitioning the IOMMU pages to Hypervisor state
         * before version 1.53. But, accounting for the number of assigned
         * 4kB pages in a 2M page was done incorrectly by not transitioning
         * to the Reclaim state. This resulted in RMP #PF when later accessing
         * the 2M page containing those pages during kexec boot. Hence, the
         * firmware now transitions these pages to Reclaim state and hypervisor
         * needs to transition these pages to shared state. SNP Firmware
         * version 1.53 and above are needed for kexec boot.
         */
        ret = amd_iommu_snp_disable();
        if (ret) {
                dev_err(sev->dev, "SNP IOMMU shutdown failed\n");
                return ret;
        }

        snp_leak_hv_fixed_pages();
        sev->snp_initialized = false;
        dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");

        /*
         * __sev_snp_shutdown_locked() deadlocks when it tries to unregister
         * itself during panic as the panic notifier is called with RCU read
         * lock held and notifier unregistration does RCU synchronization.
         */
        if (!panic)
                atomic_notifier_chain_unregister(&panic_notifier_list,
                                                 &snp_panic_notifier);

        /* Reset TMR size back to default */
        sev_es_tmr_size = SEV_TMR_SIZE;

        return ret;
}

static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_user_data_pek_cert_import input;
        struct sev_data_pek_cert_import data;
        bool shutdown_required = false;
        void *pek_blob, *oca_blob;
        int ret;

        if (!writable)
                return -EPERM;

        if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
                return -EFAULT;

        /* copy PEK certificate blobs from userspace */
        pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
        if (IS_ERR(pek_blob))
                return PTR_ERR(pek_blob);

        data.reserved = 0;
        data.pek_cert_address = __psp_pa(pek_blob);
        data.pek_cert_len = input.pek_cert_len;

        /* copy PEK certificate blobs from userspace */
        oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
        if (IS_ERR(oca_blob)) {
                ret = PTR_ERR(oca_blob);
                goto e_free_pek;
        }

        data.oca_cert_address = __psp_pa(oca_blob);
        data.oca_cert_len = input.oca_cert_len;

        /* If platform is not in INIT state then transition it to INIT */
        if (sev->sev_plat_status.state != SEV_STATE_INIT) {
                ret = sev_move_to_init_state(argp, &shutdown_required);
                if (ret)
                        goto e_free_oca;
        }

        ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);

e_free_oca:
        if (shutdown_required)
                __sev_firmware_shutdown(sev, false);

        kfree(oca_blob);
e_free_pek:
        kfree(pek_blob);
        return ret;
}

static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
{
        struct sev_user_data_get_id2 input;
        struct sev_data_get_id data;
        void __user *input_address;
        void *id_blob = NULL;
        int ret;

        /* SEV GET_ID is available from SEV API v0.16 and up */
        if (!sev_version_greater_or_equal(0, 16))
                return -ENOTSUPP;

        if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
                return -EFAULT;

        input_address = (void __user *)input.address;

        if (input.address && input.length) {
                /*
                 * The length of the ID shouldn't be assumed by software since
                 * it may change in the future.  The allocation size is limited
                 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator.
                 * If the allocation fails, simply return ENOMEM rather than
                 * warning in the kernel log.
                 */
                id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
                if (!id_blob)
                        return -ENOMEM;

                data.address = __psp_pa(id_blob);
                data.len = input.length;
        } else {
                data.address = 0;
                data.len = 0;
        }

        ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);

        /*
         * Firmware will return the length of the ID value (either the minimum
         * required length or the actual length written), return it to the user.
         */
        input.length = data.len;

        if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
                ret = -EFAULT;
                goto e_free;
        }

        if (id_blob) {
                if (copy_to_user(input_address, id_blob, data.len)) {
                        ret = -EFAULT;
                        goto e_free;
                }
        }

e_free:
        kfree(id_blob);

        return ret;
}

static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
{
        struct sev_data_get_id *data;
        u64 data_size, user_size;
        void *id_blob, *mem;
        int ret;

        /* SEV GET_ID available from SEV API v0.16 and up */
        if (!sev_version_greater_or_equal(0, 16))
                return -ENOTSUPP;

        /* SEV FW expects the buffer it fills with the ID to be
         * 8-byte aligned. Memory allocated should be enough to
         * hold data structure + alignment padding + memory
         * where SEV FW writes the ID.
         */
        data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
        user_size = sizeof(struct sev_user_data_get_id);

        mem = kzalloc(data_size + user_size, GFP_KERNEL);
        if (!mem)
                return -ENOMEM;

        data = mem;
        id_blob = mem + data_size;

        data->address = __psp_pa(id_blob);
        data->len = user_size;

        ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
        if (!ret) {
                if (copy_to_user((void __user *)argp->data, id_blob, data->len))
                        ret = -EFAULT;
        }

        kfree(mem);

        return ret;
}

static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_user_data_pdh_cert_export input;
        void *pdh_blob = NULL, *cert_blob = NULL;
        struct sev_data_pdh_cert_export data;
        void __user *input_cert_chain_address;
        void __user *input_pdh_cert_address;
        bool shutdown_required = false;
        int ret;

        if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
                return -EFAULT;

        memset(&data, 0, sizeof(data));

        input_pdh_cert_address = (void __user *)input.pdh_cert_address;
        input_cert_chain_address = (void __user *)input.cert_chain_address;

        /* Userspace wants to query the certificate length. */
        if (!input.pdh_cert_address ||
            !input.pdh_cert_len ||
            !input.cert_chain_address)
                goto cmd;

        /* Allocate a physically contiguous buffer to store the PDH blob. */
        if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
                return -EFAULT;

        /* Allocate a physically contiguous buffer to store the cert chain blob. */
        if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
                return -EFAULT;

        pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
        if (!pdh_blob)
                return -ENOMEM;

        data.pdh_cert_address = __psp_pa(pdh_blob);
        data.pdh_cert_len = input.pdh_cert_len;

        cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
        if (!cert_blob) {
                ret = -ENOMEM;
                goto e_free_pdh;
        }

        data.cert_chain_address = __psp_pa(cert_blob);
        data.cert_chain_len = input.cert_chain_len;

cmd:
        /* If platform is not in INIT state then transition it to INIT. */
        if (sev->sev_plat_status.state != SEV_STATE_INIT) {
                if (!writable) {
                        ret = -EPERM;
                        goto e_free_cert;
                }
                ret = sev_move_to_init_state(argp, &shutdown_required);
                if (ret)
                        goto e_free_cert;
        }

        ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);

        /* If we query the length, FW responded with expected data. */
        input.cert_chain_len = data.cert_chain_len;
        input.pdh_cert_len = data.pdh_cert_len;

        if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
                ret = -EFAULT;
                goto e_free_cert;
        }

        if (pdh_blob) {
                if (copy_to_user(input_pdh_cert_address,
                                 pdh_blob, input.pdh_cert_len)) {
                        ret = -EFAULT;
                        goto e_free_cert;
                }
        }

        if (cert_blob) {
                if (copy_to_user(input_cert_chain_address,
                                 cert_blob, input.cert_chain_len))
                        ret = -EFAULT;
        }

e_free_cert:
        if (shutdown_required)
                __sev_firmware_shutdown(sev, false);

        kfree(cert_blob);
e_free_pdh:
        kfree(pdh_blob);
        return ret;
}

static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_data_snp_addr buf;
        struct page *status_page;
        void *data;
        int ret;

        if (!argp->data)
                return -EINVAL;

        status_page = alloc_page(GFP_KERNEL_ACCOUNT);
        if (!status_page)
                return -ENOMEM;

        data = page_address(status_page);

        /*
         * SNP_PLATFORM_STATUS can be executed in any SNP state. But if executed
         * when SNP has been initialized, the status page must be firmware-owned.
         */
        if (sev->snp_initialized) {
                /*
                 * Firmware expects the status page to be in Firmware state,
                 * otherwise it will report an error INVALID_PAGE_STATE.
                 */
                if (rmp_mark_pages_firmware(__pa(data), 1, true)) {
                        ret = -EFAULT;
                        goto cleanup;
                }
        }

        buf.address = __psp_pa(data);
        ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error);

        if (sev->snp_initialized) {
                /*
                 * The status page will be in Reclaim state on success, or left
                 * in Firmware state on failure. Use snp_reclaim_pages() to
                 * transition either case back to Hypervisor-owned state.
                 */
                if (snp_reclaim_pages(__pa(data), 1, true))
                        return -EFAULT;
        }

        if (ret)
                goto cleanup;

        if (copy_to_user((void __user *)argp->data, data,
                         sizeof(struct sev_user_data_snp_status)))
                ret = -EFAULT;

cleanup:
        __free_pages(status_page, 0);
        return ret;
}

static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_data_snp_commit buf;
        bool shutdown_required = false;
        int ret, error;

        if (!sev->snp_initialized) {
                ret = snp_move_to_init_state(argp, &shutdown_required);
                if (ret)
                        return ret;
        }

        buf.len = sizeof(buf);

        ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error);

        if (shutdown_required)
                __sev_snp_shutdown_locked(&error, false);

        return ret;
}

static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_user_data_snp_config config;
        bool shutdown_required = false;
        int ret, error;

        if (!argp->data)
                return -EINVAL;

        if (!writable)
                return -EPERM;

        if (copy_from_user(&config, (void __user *)argp->data, sizeof(config)))
                return -EFAULT;

        if (!sev->snp_initialized) {
                ret = snp_move_to_init_state(argp, &shutdown_required);
                if (ret)
                        return ret;
        }

        ret = __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error);

        if (shutdown_required)
                __sev_snp_shutdown_locked(&error, false);

        return ret;
}

static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable)
{
        struct sev_device *sev = psp_master->sev_data;
        struct sev_user_data_snp_vlek_load input;
        bool shutdown_required = false;
        int ret, error;
        void *blob;

        if (!argp->data)
                return -EINVAL;

        if (!writable)
                return -EPERM;

        if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input)))
                return -EFAULT;

        if (input.len != sizeof(input) || input.vlek_wrapped_version != 0)
                return -EINVAL;

        blob = psp_copy_user_blob(input.vlek_wrapped_address,
                                  sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick));
        if (IS_ERR(blob))
                return PTR_ERR(blob);

        input.vlek_wrapped_address = __psp_pa(blob);

        if (!sev->snp_initialized) {
                ret = snp_move_to_init_state(argp, &shutdown_required);
                if (ret)
                        goto cleanup;
        }

        ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error);

        if (shutdown_required)
                __sev_snp_shutdown_locked(&error, false);

cleanup:
        kfree(blob);

        return ret;
}

static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
{
        void __user *argp = (void __user *)arg;
        struct sev_issue_cmd input;
        int ret = -EFAULT;
        bool writable = file->f_mode & FMODE_WRITE;

        if (!psp_master || !psp_master->sev_data)
                return -ENODEV;

        if (ioctl != SEV_ISSUE_CMD)
                return -EINVAL;

        if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
                return -EFAULT;

        if (input.cmd > SEV_MAX)
                return -EINVAL;

        mutex_lock(&sev_cmd_mutex);

        switch (input.cmd) {

        case SEV_FACTORY_RESET:
                ret = sev_ioctl_do_reset(&input, writable);
                break;
        case SEV_PLATFORM_STATUS:
                ret = sev_ioctl_do_platform_status(&input);
                break;
        case SEV_PEK_GEN:
                ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
                break;
        case SEV_PDH_GEN:
                ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
                break;
        case SEV_PEK_CSR:
                ret = sev_ioctl_do_pek_csr(&input, writable);
                break;
        case SEV_PEK_CERT_IMPORT:
                ret = sev_ioctl_do_pek_import(&input, writable);
                break;
        case SEV_PDH_CERT_EXPORT:
                ret = sev_ioctl_do_pdh_export(&input, writable);
                break;
        case SEV_GET_ID:
                pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
                ret = sev_ioctl_do_get_id(&input);
                break;
        case SEV_GET_ID2:
                ret = sev_ioctl_do_get_id2(&input);
                break;
        case SNP_PLATFORM_STATUS:
                ret = sev_ioctl_do_snp_platform_status(&input);
                break;
        case SNP_COMMIT:
                ret = sev_ioctl_do_snp_commit(&input);
                break;
        case SNP_SET_CONFIG:
                ret = sev_ioctl_do_snp_set_config(&input, writable);
                break;
        case SNP_VLEK_LOAD:
                ret = sev_ioctl_do_snp_vlek_load(&input, writable);
                break;
        default:
                ret = -EINVAL;
                goto out;
        }

        if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
                ret = -EFAULT;
out:
        mutex_unlock(&sev_cmd_mutex);

        return ret;
}

static const struct file_operations sev_fops = {
        .owner  = THIS_MODULE,
        .unlocked_ioctl = sev_ioctl,
};

int sev_platform_status(struct sev_user_data_status *data, int *error)
{
        return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
}
EXPORT_SYMBOL_GPL(sev_platform_status);

int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
{
        return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
}
EXPORT_SYMBOL_GPL(sev_guest_deactivate);

int sev_guest_activate(struct sev_data_activate *data, int *error)
{
        return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
}
EXPORT_SYMBOL_GPL(sev_guest_activate);

int sev_guest_decommission(struct sev_data_decommission *data, int *error)
{
        return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
}
EXPORT_SYMBOL_GPL(sev_guest_decommission);

int sev_guest_df_flush(int *error)
{
        return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
}
EXPORT_SYMBOL_GPL(sev_guest_df_flush);

static void sev_exit(struct kref *ref)
{
        misc_deregister(&misc_dev->misc);
        kfree(misc_dev);
        misc_dev = NULL;
}

static int sev_misc_init(struct sev_device *sev)
{
        struct device *dev = sev->dev;
        int ret;

        /*
         * SEV feature support can be detected on multiple devices but the SEV
         * FW commands must be issued on the master. During probe, we do not
         * know the master hence we create /dev/sev on the first device probe.
         * sev_do_cmd() finds the right master device to which to issue the
         * command to the firmware.
         */
        if (!misc_dev) {
                struct miscdevice *misc;

                misc_dev = kzalloc_obj(*misc_dev);
                if (!misc_dev)
                        return -ENOMEM;

                misc = &misc_dev->misc;
                misc->minor = MISC_DYNAMIC_MINOR;
                misc->name = DEVICE_NAME;
                misc->fops = &sev_fops;

                ret = misc_register(misc);
                if (ret)
                        return ret;

                kref_init(&misc_dev->refcount);
        } else {
                kref_get(&misc_dev->refcount);
        }

        init_waitqueue_head(&sev->int_queue);
        sev->misc = misc_dev;
        dev_dbg(dev, "registered SEV device\n");

        return 0;
}

int sev_dev_init(struct psp_device *psp)
{
        struct device *dev = psp->dev;
        struct sev_device *sev;
        int ret = -ENOMEM;

        if (!boot_cpu_has(X86_FEATURE_SEV)) {
                dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
                return 0;
        }

        sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
        if (!sev)
                goto e_err;

        sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1);
        if (!sev->cmd_buf)
                goto e_sev;

        sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE;

        psp->sev_data = sev;

        sev->dev = dev;
        sev->psp = psp;

        sev->io_regs = psp->io_regs;

        sev->vdata = (struct sev_vdata *)psp->vdata->sev;
        if (!sev->vdata) {
                ret = -ENODEV;
                dev_err(dev, "sev: missing driver data\n");
                goto e_buf;
        }

        psp_set_sev_irq_handler(psp, sev_irq_handler, sev);

        ret = sev_misc_init(sev);
        if (ret)
                goto e_irq;

        dev_notice(dev, "sev enabled\n");

        return 0;

e_irq:
        psp_clear_sev_irq_handler(psp);
e_buf:
        devm_free_pages(dev, (unsigned long)sev->cmd_buf);
e_sev:
        devm_kfree(dev, sev);
e_err:
        psp->sev_data = NULL;

        dev_notice(dev, "sev initialization failed\n");

        return ret;
}

static void __sev_firmware_shutdown(struct sev_device *sev, bool panic)
{
        int error;

        __sev_platform_shutdown_locked(&error);

        if (sev_es_tmr) {
                /*
                 * The TMR area was encrypted, flush it from the cache.
                 *
                 * If invoked during panic handling, local interrupts are
                 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus()
                 * can't be used. In that case, wbinvd() is done on remote CPUs
                 * via the NMI callback, and done for this CPU later during
                 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped.
                 */
                if (!panic)
                        wbinvd_on_all_cpus();

                __snp_free_firmware_pages(virt_to_page(sev_es_tmr),
                                          get_order(sev_es_tmr_size),
                                          true);
                sev_es_tmr = NULL;
        }

        if (sev_init_ex_buffer) {
                __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer),
                                          get_order(NV_LENGTH),
                                          true);
                sev_init_ex_buffer = NULL;
        }

        __sev_snp_shutdown_locked(&error, panic);
}

static void sev_firmware_shutdown(struct sev_device *sev)
{
        /*
         * Calling without sev_cmd_mutex held as TSM will likely try disconnecting
         * IDE and this ends up calling sev_do_cmd() which locks sev_cmd_mutex.
         */
        if (sev->tio_status)
                sev_tsm_uninit(sev);

        mutex_lock(&sev_cmd_mutex);

        __sev_firmware_shutdown(sev, false);

        kfree(sev->tio_status);
        sev->tio_status = NULL;

        mutex_unlock(&sev_cmd_mutex);
}

void sev_platform_shutdown(void)
{
        if (!psp_master || !psp_master->sev_data)
                return;

        sev_firmware_shutdown(psp_master->sev_data);
}
EXPORT_SYMBOL_GPL(sev_platform_shutdown);

u64 sev_get_snp_policy_bits(void)
{
        struct psp_device *psp = psp_master;
        struct sev_device *sev;
        u64 policy_bits;

        if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
                return 0;

        if (!psp || !psp->sev_data)
                return 0;

        sev = psp->sev_data;

        policy_bits = SNP_POLICY_MASK_BASE;

        if (sev->snp_plat_status.feature_info) {
                if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED)
                        policy_bits |= SNP_POLICY_MASK_RAPL_DIS;

                if (sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED)
                        policy_bits |= SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM;

                if (sev->snp_feat_info_0.ecx & SNP_AES_256_XTS_POLICY_SUPPORTED)
                        policy_bits |= SNP_POLICY_MASK_MEM_AES_256_XTS;

                if (sev->snp_feat_info_0.ecx & SNP_CXL_ALLOW_POLICY_SUPPORTED)
                        policy_bits |= SNP_POLICY_MASK_CXL_ALLOW;

                if (sev_version_greater_or_equal(1, 58))
                        policy_bits |= SNP_POLICY_MASK_PAGE_SWAP_DISABLE;
        }

        return policy_bits;
}
EXPORT_SYMBOL_GPL(sev_get_snp_policy_bits);

void sev_dev_destroy(struct psp_device *psp)
{
        struct sev_device *sev = psp->sev_data;

        if (!sev)
                return;

        sev_firmware_shutdown(sev);

        if (sev->misc)
                kref_put(&misc_dev->refcount, sev_exit);

        psp_clear_sev_irq_handler(psp);
}

static int snp_shutdown_on_panic(struct notifier_block *nb,
                                 unsigned long reason, void *arg)
{
        struct sev_device *sev = psp_master->sev_data;

        /*
         * If sev_cmd_mutex is already acquired, then it's likely
         * another PSP command is in flight and issuing a shutdown
         * would fail in unexpected ways. Rather than create even
         * more confusion during a panic, just bail out here.
         */
        if (mutex_is_locked(&sev_cmd_mutex))
                return NOTIFY_DONE;

        __sev_firmware_shutdown(sev, true);

        return NOTIFY_DONE;
}

int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
                                void *data, int *error)
{
        if (!filep || filep->f_op != &sev_fops)
                return -EBADF;

        return sev_do_cmd(cmd, data, error);
}
EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);

void sev_pci_init(void)
{
        struct sev_device *sev = psp_master->sev_data;
        u8 api_major, api_minor, build;

        if (!sev)
                return;

        psp_timeout = psp_probe_timeout;

        if (sev_get_api_version())
                goto err;

        api_major = sev->api_major;
        api_minor = sev->api_minor;
        build     = sev->build;

        if (sev_update_firmware(sev->dev) == 0)
                sev_get_api_version();

        if (api_major != sev->api_major || api_minor != sev->api_minor ||
            build != sev->build)
                dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n",
                         api_major, api_minor, build,
                         sev->api_major, sev->api_minor, sev->build);

        return;

err:
        sev_dev_destroy(psp_master);

        psp_master->sev_data = NULL;
}

void sev_pci_exit(void)
{
        struct sev_device *sev = psp_master->sev_data;

        if (!sev)
                return;

        sev_firmware_shutdown(sev);
}