// SPDX-License-Identifier: GPL-2.0+
//
// Security related flags and so on.
//
// Copyright 2018, Michael Ellerman, IBM Corporation.

#include <linux/cpu.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/memblock.h>
#include <linux/nospec.h>
#include <linux/prctl.h>
#include <linux/seq_buf.h>
#include <linux/debugfs.h>

#include <asm/asm-prototypes.h>
#include <asm/text-patching.h>
#include <asm/security_features.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/inst.h>

#include "setup.h"

u64 powerpc_security_features __read_mostly = SEC_FTR_DEFAULT;

enum branch_cache_flush_type {
        BRANCH_CACHE_FLUSH_NONE = 0x1,
        BRANCH_CACHE_FLUSH_SW   = 0x2,
        BRANCH_CACHE_FLUSH_HW   = 0x4,
};
static enum branch_cache_flush_type count_cache_flush_type = BRANCH_CACHE_FLUSH_NONE;
static enum branch_cache_flush_type link_stack_flush_type = BRANCH_CACHE_FLUSH_NONE;

bool barrier_nospec_enabled;
static bool no_nospec;
static bool btb_flush_enabled;
#if defined(CONFIG_PPC_E500) || defined(CONFIG_PPC_BOOK3S_64)
static bool no_spectrev2;
#endif

static void enable_barrier_nospec(bool enable)
{
        barrier_nospec_enabled = enable;
        do_barrier_nospec_fixups(enable);
}

void __init setup_barrier_nospec(void)
{
        bool enable;

        /*
         * It would make sense to check SEC_FTR_SPEC_BAR_ORI31 below as well.
         * But there's a good reason not to. The two flags we check below are
         * both are enabled by default in the kernel, so if the hcall is not
         * functional they will be enabled.
         * On a system where the host firmware has been updated (so the ori
         * functions as a barrier), but on which the hypervisor (KVM/Qemu) has
         * not been updated, we would like to enable the barrier. Dropping the
         * check for SEC_FTR_SPEC_BAR_ORI31 achieves that. The only downside is
         * we potentially enable the barrier on systems where the host firmware
         * is not updated, but that's harmless as it's a no-op.
         */
        enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
                 security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR);

        if (!no_nospec && !cpu_mitigations_off())
                enable_barrier_nospec(enable);
}

static int __init handle_nospectre_v1(char *p)
{
        no_nospec = true;

        return 0;
}
early_param("nospectre_v1", handle_nospectre_v1);

#ifdef CONFIG_DEBUG_FS
static int barrier_nospec_set(void *data, u64 val)
{
        switch (val) {
        case 0:
        case 1:
                break;
        default:
                return -EINVAL;
        }

        if (!!val == !!barrier_nospec_enabled)
                return 0;

        enable_barrier_nospec(!!val);

        return 0;
}

static int barrier_nospec_get(void *data, u64 *val)
{
        *val = barrier_nospec_enabled ? 1 : 0;
        return 0;
}

DEFINE_DEBUGFS_ATTRIBUTE(fops_barrier_nospec, barrier_nospec_get,
                         barrier_nospec_set, "%llu\n");

static __init int barrier_nospec_debugfs_init(void)
{
        debugfs_create_file_unsafe("barrier_nospec", 0600,
                                   arch_debugfs_dir, NULL,
                                   &fops_barrier_nospec);
        return 0;
}
device_initcall(barrier_nospec_debugfs_init);

static __init int security_feature_debugfs_init(void)
{
        debugfs_create_x64("security_features", 0400, arch_debugfs_dir,
                           &powerpc_security_features);
        return 0;
}
device_initcall(security_feature_debugfs_init);
#endif /* CONFIG_DEBUG_FS */

#if defined(CONFIG_PPC_E500) || defined(CONFIG_PPC_BOOK3S_64)
static int __init handle_nospectre_v2(char *p)
{
        no_spectrev2 = true;

        return 0;
}
early_param("nospectre_v2", handle_nospectre_v2);
#endif /* CONFIG_PPC_E500 || CONFIG_PPC_BOOK3S_64 */

#ifdef CONFIG_PPC_E500
void __init setup_spectre_v2(void)
{
        if (no_spectrev2 || cpu_mitigations_off())
                do_btb_flush_fixups();
        else
                btb_flush_enabled = true;
}
#endif /* CONFIG_PPC_E500 */

#ifdef CONFIG_PPC_BOOK3S_64
ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
{
        bool thread_priv;

        thread_priv = security_ftr_enabled(SEC_FTR_L1D_THREAD_PRIV);

        if (rfi_flush) {
                struct seq_buf s;
                seq_buf_init(&s, buf, PAGE_SIZE - 1);

                seq_buf_printf(&s, "Mitigation: RFI Flush");
                if (thread_priv)
                        seq_buf_printf(&s, ", L1D private per thread");

                seq_buf_printf(&s, "\n");

                return s.len;
        }

        if (thread_priv)
                return sprintf(buf, "Vulnerable: L1D private per thread\n");

        if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) &&
            !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR))
                return sprintf(buf, "Not affected\n");

        return sprintf(buf, "Vulnerable\n");
}

ssize_t cpu_show_l1tf(struct device *dev, struct device_attribute *attr, char *buf)
{
        return cpu_show_meltdown(dev, attr, buf);
}
#endif

ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct seq_buf s;

        seq_buf_init(&s, buf, PAGE_SIZE - 1);

        if (security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR)) {
                if (barrier_nospec_enabled)
                        seq_buf_printf(&s, "Mitigation: __user pointer sanitization");
                else
                        seq_buf_printf(&s, "Vulnerable");

                if (security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31))
                        seq_buf_printf(&s, ", ori31 speculation barrier enabled");

                seq_buf_printf(&s, "\n");
        } else
                seq_buf_printf(&s, "Not affected\n");

        return s.len;
}

ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct seq_buf s;
        bool bcs, ccd;

        seq_buf_init(&s, buf, PAGE_SIZE - 1);

        bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED);
        ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED);

        if (bcs || ccd) {
                seq_buf_printf(&s, "Mitigation: ");

                if (bcs)
                        seq_buf_printf(&s, "Indirect branch serialisation (kernel only)");

                if (bcs && ccd)
                        seq_buf_printf(&s, ", ");

                if (ccd)
                        seq_buf_printf(&s, "Indirect branch cache disabled");

        } else if (count_cache_flush_type != BRANCH_CACHE_FLUSH_NONE) {
                seq_buf_printf(&s, "Mitigation: Software count cache flush");

                if (count_cache_flush_type == BRANCH_CACHE_FLUSH_HW)
                        seq_buf_printf(&s, " (hardware accelerated)");

        } else if (btb_flush_enabled) {
                seq_buf_printf(&s, "Mitigation: Branch predictor state flush");
        } else {
                seq_buf_printf(&s, "Vulnerable");
        }

        if (bcs || ccd || count_cache_flush_type != BRANCH_CACHE_FLUSH_NONE) {
                if (link_stack_flush_type != BRANCH_CACHE_FLUSH_NONE)
                        seq_buf_printf(&s, ", Software link stack flush");
                if (link_stack_flush_type == BRANCH_CACHE_FLUSH_HW)
                        seq_buf_printf(&s, " (hardware accelerated)");
        }

        seq_buf_printf(&s, "\n");

        return s.len;
}

#ifdef CONFIG_PPC_BOOK3S_64
/*
 * Store-forwarding barrier support.
 */

static enum stf_barrier_type stf_enabled_flush_types;
static bool no_stf_barrier;
static bool stf_barrier;

static int __init handle_no_stf_barrier(char *p)
{
        pr_info("stf-barrier: disabled on command line.");
        no_stf_barrier = true;
        return 0;
}

early_param("no_stf_barrier", handle_no_stf_barrier);

enum stf_barrier_type stf_barrier_type_get(void)
{
        return stf_enabled_flush_types;
}

/* This is the generic flag used by other architectures */
static int __init handle_ssbd(char *p)
{
        if (!p || strncmp(p, "auto", 5) == 0 || strncmp(p, "on", 2) == 0 ) {
                /* Until firmware tells us, we have the barrier with auto */
                return 0;
        } else if (strncmp(p, "off", 3) == 0) {
                handle_no_stf_barrier(NULL);
                return 0;
        } else
                return 1;

        return 0;
}
early_param("spec_store_bypass_disable", handle_ssbd);

/* This is the generic flag used by other architectures */
static int __init handle_no_ssbd(char *p)
{
        handle_no_stf_barrier(NULL);
        return 0;
}
early_param("nospec_store_bypass_disable", handle_no_ssbd);

static void stf_barrier_enable(bool enable)
{
        if (enable)
                do_stf_barrier_fixups(stf_enabled_flush_types);
        else
                do_stf_barrier_fixups(STF_BARRIER_NONE);

        stf_barrier = enable;
}

void setup_stf_barrier(void)
{
        enum stf_barrier_type type;
        bool enable;

        /* Default to fallback in case fw-features are not available */
        if (cpu_has_feature(CPU_FTR_ARCH_300))
                type = STF_BARRIER_EIEIO;
        else if (cpu_has_feature(CPU_FTR_ARCH_207S))
                type = STF_BARRIER_SYNC_ORI;
        else if (cpu_has_feature(CPU_FTR_ARCH_206))
                type = STF_BARRIER_FALLBACK;
        else
                type = STF_BARRIER_NONE;

        enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
                 security_ftr_enabled(SEC_FTR_STF_BARRIER);

        if (type == STF_BARRIER_FALLBACK) {
                pr_info("stf-barrier: fallback barrier available\n");
        } else if (type == STF_BARRIER_SYNC_ORI) {
                pr_info("stf-barrier: hwsync barrier available\n");
        } else if (type == STF_BARRIER_EIEIO) {
                pr_info("stf-barrier: eieio barrier available\n");
        }

        stf_enabled_flush_types = type;

        if (!no_stf_barrier && !cpu_mitigations_off())
                stf_barrier_enable(enable);
}

ssize_t cpu_show_spec_store_bypass(struct device *dev, struct device_attribute *attr, char *buf)
{
        if (stf_barrier && stf_enabled_flush_types != STF_BARRIER_NONE) {
                const char *type;
                switch (stf_enabled_flush_types) {
                case STF_BARRIER_EIEIO:
                        type = "eieio";
                        break;
                case STF_BARRIER_SYNC_ORI:
                        type = "hwsync";
                        break;
                case STF_BARRIER_FALLBACK:
                        type = "fallback";
                        break;
                default:
                        type = "unknown";
                }
                return sprintf(buf, "Mitigation: Kernel entry/exit barrier (%s)\n", type);
        }

        if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) &&
            !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR))
                return sprintf(buf, "Not affected\n");

        return sprintf(buf, "Vulnerable\n");
}

static int ssb_prctl_get(struct task_struct *task)
{
        /*
         * The STF_BARRIER feature is on by default, so if it's off that means
         * firmware has explicitly said the CPU is not vulnerable via either
         * the hypercall or device tree.
         */
        if (!security_ftr_enabled(SEC_FTR_STF_BARRIER))
                return PR_SPEC_NOT_AFFECTED;

        /*
         * If the system's CPU has no known barrier (see setup_stf_barrier())
         * then assume that the CPU is not vulnerable.
         */
        if (stf_enabled_flush_types == STF_BARRIER_NONE)
                return PR_SPEC_NOT_AFFECTED;

        /*
         * Otherwise the CPU is vulnerable. The barrier is not a global or
         * per-process mitigation, so the only value that can be reported here
         * is PR_SPEC_ENABLE, which appears as "vulnerable" in /proc.
         */
        return PR_SPEC_ENABLE;
}

int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which)
{
        switch (which) {
        case PR_SPEC_STORE_BYPASS:
                return ssb_prctl_get(task);
        default:
                return -ENODEV;
        }
}

#ifdef CONFIG_DEBUG_FS
static int stf_barrier_set(void *data, u64 val)
{
        bool enable;

        if (val == 1)
                enable = true;
        else if (val == 0)
                enable = false;
        else
                return -EINVAL;

        /* Only do anything if we're changing state */
        if (enable != stf_barrier)
                stf_barrier_enable(enable);

        return 0;
}

static int stf_barrier_get(void *data, u64 *val)
{
        *val = stf_barrier ? 1 : 0;
        return 0;
}

DEFINE_DEBUGFS_ATTRIBUTE(fops_stf_barrier, stf_barrier_get, stf_barrier_set,
                         "%llu\n");

static __init int stf_barrier_debugfs_init(void)
{
        debugfs_create_file_unsafe("stf_barrier", 0600, arch_debugfs_dir,
                                   NULL, &fops_stf_barrier);
        return 0;
}
device_initcall(stf_barrier_debugfs_init);
#endif /* CONFIG_DEBUG_FS */

static void update_branch_cache_flush(void)
{
        u32 *site, __maybe_unused *site2;

#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
        site = &patch__call_kvm_flush_link_stack;
        site2 = &patch__call_kvm_flush_link_stack_p9;
        // This controls the branch from guest_exit_cont to kvm_flush_link_stack
        if (link_stack_flush_type == BRANCH_CACHE_FLUSH_NONE) {
                patch_instruction_site(site, ppc_inst(PPC_RAW_NOP()));
                patch_instruction_site(site2, ppc_inst(PPC_RAW_NOP()));
        } else {
                // Could use HW flush, but that could also flush count cache
                patch_branch_site(site, (u64)&kvm_flush_link_stack, BRANCH_SET_LINK);
                patch_branch_site(site2, (u64)&kvm_flush_link_stack, BRANCH_SET_LINK);
        }
#endif

        // Patch out the bcctr first, then nop the rest
        site = &patch__call_flush_branch_caches3;
        patch_instruction_site(site, ppc_inst(PPC_RAW_NOP()));
        site = &patch__call_flush_branch_caches2;
        patch_instruction_site(site, ppc_inst(PPC_RAW_NOP()));
        site = &patch__call_flush_branch_caches1;
        patch_instruction_site(site, ppc_inst(PPC_RAW_NOP()));

        // This controls the branch from _switch to flush_branch_caches
        if (count_cache_flush_type == BRANCH_CACHE_FLUSH_NONE &&
            link_stack_flush_type == BRANCH_CACHE_FLUSH_NONE) {
                // Nothing to be done

        } else if (count_cache_flush_type == BRANCH_CACHE_FLUSH_HW &&
                   link_stack_flush_type == BRANCH_CACHE_FLUSH_HW) {
                // Patch in the bcctr last
                site = &patch__call_flush_branch_caches1;
                patch_instruction_site(site, ppc_inst(0x39207fff)); // li r9,0x7fff
                site = &patch__call_flush_branch_caches2;
                patch_instruction_site(site, ppc_inst(0x7d2903a6)); // mtctr r9
                site = &patch__call_flush_branch_caches3;
                patch_instruction_site(site, ppc_inst(PPC_INST_BCCTR_FLUSH));

        } else {
                patch_branch_site(site, (u64)&flush_branch_caches, BRANCH_SET_LINK);

                // If we just need to flush the link stack, early return
                if (count_cache_flush_type == BRANCH_CACHE_FLUSH_NONE) {
                        patch_instruction_site(&patch__flush_link_stack_return,
                                               ppc_inst(PPC_RAW_BLR()));

                // If we have flush instruction, early return
                } else if (count_cache_flush_type == BRANCH_CACHE_FLUSH_HW) {
                        patch_instruction_site(&patch__flush_count_cache_return,
                                               ppc_inst(PPC_RAW_BLR()));
                }
        }
}

static void toggle_branch_cache_flush(bool enable)
{
        if (!enable || !security_ftr_enabled(SEC_FTR_FLUSH_COUNT_CACHE)) {
                if (count_cache_flush_type != BRANCH_CACHE_FLUSH_NONE)
                        count_cache_flush_type = BRANCH_CACHE_FLUSH_NONE;

                pr_info("count-cache-flush: flush disabled.\n");
        } else {
                if (security_ftr_enabled(SEC_FTR_BCCTR_FLUSH_ASSIST)) {
                        count_cache_flush_type = BRANCH_CACHE_FLUSH_HW;
                        pr_info("count-cache-flush: hardware flush enabled.\n");
                } else {
                        count_cache_flush_type = BRANCH_CACHE_FLUSH_SW;
                        pr_info("count-cache-flush: software flush enabled.\n");
                }
        }

        if (!enable || !security_ftr_enabled(SEC_FTR_FLUSH_LINK_STACK)) {
                if (link_stack_flush_type != BRANCH_CACHE_FLUSH_NONE)
                        link_stack_flush_type = BRANCH_CACHE_FLUSH_NONE;

                pr_info("link-stack-flush: flush disabled.\n");
        } else {
                if (security_ftr_enabled(SEC_FTR_BCCTR_LINK_FLUSH_ASSIST)) {
                        link_stack_flush_type = BRANCH_CACHE_FLUSH_HW;
                        pr_info("link-stack-flush: hardware flush enabled.\n");
                } else {
                        link_stack_flush_type = BRANCH_CACHE_FLUSH_SW;
                        pr_info("link-stack-flush: software flush enabled.\n");
                }
        }

        update_branch_cache_flush();
}

void setup_count_cache_flush(void)
{
        bool enable = true;

        if (no_spectrev2 || cpu_mitigations_off()) {
                if (security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED) ||
                    security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED))
                        pr_warn("Spectre v2 mitigations not fully under software control, can't disable\n");

                enable = false;
        }

        /*
         * There's no firmware feature flag/hypervisor bit to tell us we need to
         * flush the link stack on context switch. So we set it here if we see
         * either of the Spectre v2 mitigations that aim to protect userspace.
         */
        if (security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED) ||
            security_ftr_enabled(SEC_FTR_FLUSH_COUNT_CACHE))
                security_ftr_set(SEC_FTR_FLUSH_LINK_STACK);

        toggle_branch_cache_flush(enable);
}

static enum l1d_flush_type enabled_flush_types;
static void *l1d_flush_fallback_area;
static bool no_rfi_flush;
static bool no_entry_flush;
static bool no_uaccess_flush;
bool rfi_flush;
static bool entry_flush;
static bool uaccess_flush;
DEFINE_STATIC_KEY_FALSE(uaccess_flush_key);
EXPORT_SYMBOL(uaccess_flush_key);

static int __init handle_no_rfi_flush(char *p)
{
        pr_info("rfi-flush: disabled on command line.");
        no_rfi_flush = true;
        return 0;
}
early_param("no_rfi_flush", handle_no_rfi_flush);

static int __init handle_no_entry_flush(char *p)
{
        pr_info("entry-flush: disabled on command line.");
        no_entry_flush = true;
        return 0;
}
early_param("no_entry_flush", handle_no_entry_flush);

static int __init handle_no_uaccess_flush(char *p)
{
        pr_info("uaccess-flush: disabled on command line.");
        no_uaccess_flush = true;
        return 0;
}
early_param("no_uaccess_flush", handle_no_uaccess_flush);

/*
 * The RFI flush is not KPTI, but because users will see doco that says to use
 * nopti we hijack that option here to also disable the RFI flush.
 */
static int __init handle_no_pti(char *p)
{
        pr_info("rfi-flush: disabling due to 'nopti' on command line.\n");
        handle_no_rfi_flush(NULL);
        return 0;
}
early_param("nopti", handle_no_pti);

static void do_nothing(void *unused)
{
        /*
         * We don't need to do the flush explicitly, just enter+exit kernel is
         * sufficient, the RFI exit handlers will do the right thing.
         */
}

void rfi_flush_enable(bool enable)
{
        if (enable) {
                do_rfi_flush_fixups(enabled_flush_types);
                on_each_cpu(do_nothing, NULL, 1);
        } else
                do_rfi_flush_fixups(L1D_FLUSH_NONE);

        rfi_flush = enable;
}

static void entry_flush_enable(bool enable)
{
        if (enable) {
                do_entry_flush_fixups(enabled_flush_types);
                on_each_cpu(do_nothing, NULL, 1);
        } else {
                do_entry_flush_fixups(L1D_FLUSH_NONE);
        }

        entry_flush = enable;
}

static void uaccess_flush_enable(bool enable)
{
        if (enable) {
                do_uaccess_flush_fixups(enabled_flush_types);
                static_branch_enable(&uaccess_flush_key);
                on_each_cpu(do_nothing, NULL, 1);
        } else {
                static_branch_disable(&uaccess_flush_key);
                do_uaccess_flush_fixups(L1D_FLUSH_NONE);
        }

        uaccess_flush = enable;
}

static void __ref init_fallback_flush(void)
{
        u64 l1d_size, limit;
        int cpu;

        /* Only allocate the fallback flush area once (at boot time). */
        if (l1d_flush_fallback_area)
                return;

        l1d_size = ppc64_caches.l1d.size;

        /*
         * If there is no d-cache-size property in the device tree, l1d_size
         * could be zero. That leads to the loop in the asm wrapping around to
         * 2^64-1, and then walking off the end of the fallback area and
         * eventually causing a page fault which is fatal. Just default to
         * something vaguely sane.
         */
        if (!l1d_size)
                l1d_size = (64 * 1024);

        limit = min(ppc64_bolted_size(), ppc64_rma_size);

        /*
         * Align to L1d size, and size it at 2x L1d size, to catch possible
         * hardware prefetch runoff. We don't have a recipe for load patterns to
         * reliably avoid the prefetcher.
         */
        l1d_flush_fallback_area = memblock_alloc_try_nid(l1d_size * 2,
                                                l1d_size, MEMBLOCK_LOW_LIMIT,
                                                limit, NUMA_NO_NODE);
        if (!l1d_flush_fallback_area)
                panic("%s: Failed to allocate %llu bytes align=0x%llx max_addr=%pa\n",
                      __func__, l1d_size * 2, l1d_size, &limit);


        for_each_possible_cpu(cpu) {
                struct paca_struct *paca = paca_ptrs[cpu];
                paca->rfi_flush_fallback_area = l1d_flush_fallback_area;
                paca->l1d_flush_size = l1d_size;
        }
}

void setup_rfi_flush(enum l1d_flush_type types, bool enable)
{
        if (types & L1D_FLUSH_FALLBACK) {
                pr_info("rfi-flush: fallback displacement flush available\n");
                init_fallback_flush();
        }

        if (types & L1D_FLUSH_ORI)
                pr_info("rfi-flush: ori type flush available\n");

        if (types & L1D_FLUSH_MTTRIG)
                pr_info("rfi-flush: mttrig type flush available\n");

        enabled_flush_types = types;

        if (!cpu_mitigations_off() && !no_rfi_flush)
                rfi_flush_enable(enable);
}

void setup_entry_flush(bool enable)
{
        if (cpu_mitigations_off())
                return;

        if (!no_entry_flush)
                entry_flush_enable(enable);
}

void setup_uaccess_flush(bool enable)
{
        if (cpu_mitigations_off())
                return;

        if (!no_uaccess_flush)
                uaccess_flush_enable(enable);
}

#ifdef CONFIG_DEBUG_FS
static int count_cache_flush_set(void *data, u64 val)
{
        bool enable;

        if (val == 1)
                enable = true;
        else if (val == 0)
                enable = false;
        else
                return -EINVAL;

        toggle_branch_cache_flush(enable);

        return 0;
}

static int count_cache_flush_get(void *data, u64 *val)
{
        if (count_cache_flush_type == BRANCH_CACHE_FLUSH_NONE)
                *val = 0;
        else
                *val = 1;

        return 0;
}

static int link_stack_flush_get(void *data, u64 *val)
{
        if (link_stack_flush_type == BRANCH_CACHE_FLUSH_NONE)
                *val = 0;
        else
                *val = 1;

        return 0;
}

DEFINE_DEBUGFS_ATTRIBUTE(fops_count_cache_flush, count_cache_flush_get,
                         count_cache_flush_set, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_link_stack_flush, link_stack_flush_get,
                         count_cache_flush_set, "%llu\n");

static __init int count_cache_flush_debugfs_init(void)
{
        debugfs_create_file_unsafe("count_cache_flush", 0600,
                                   arch_debugfs_dir, NULL,
                                   &fops_count_cache_flush);
        debugfs_create_file_unsafe("link_stack_flush", 0600,
                                   arch_debugfs_dir, NULL,
                                   &fops_link_stack_flush);
        return 0;
}
device_initcall(count_cache_flush_debugfs_init);

static int rfi_flush_set(void *data, u64 val)
{
        bool enable;

        if (val == 1)
                enable = true;
        else if (val == 0)
                enable = false;
        else
                return -EINVAL;

        /* Only do anything if we're changing state */
        if (enable != rfi_flush)
                rfi_flush_enable(enable);

        return 0;
}

static int rfi_flush_get(void *data, u64 *val)
{
        *val = rfi_flush ? 1 : 0;
        return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set, "%llu\n");

static int entry_flush_set(void *data, u64 val)
{
        bool enable;

        if (val == 1)
                enable = true;
        else if (val == 0)
                enable = false;
        else
                return -EINVAL;

        /* Only do anything if we're changing state */
        if (enable != entry_flush)
                entry_flush_enable(enable);

        return 0;
}

static int entry_flush_get(void *data, u64 *val)
{
        *val = entry_flush ? 1 : 0;
        return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(fops_entry_flush, entry_flush_get, entry_flush_set, "%llu\n");

static int uaccess_flush_set(void *data, u64 val)
{
        bool enable;

        if (val == 1)
                enable = true;
        else if (val == 0)
                enable = false;
        else
                return -EINVAL;

        /* Only do anything if we're changing state */
        if (enable != uaccess_flush)
                uaccess_flush_enable(enable);

        return 0;
}

static int uaccess_flush_get(void *data, u64 *val)
{
        *val = uaccess_flush ? 1 : 0;
        return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(fops_uaccess_flush, uaccess_flush_get, uaccess_flush_set, "%llu\n");

static __init int rfi_flush_debugfs_init(void)
{
        debugfs_create_file("rfi_flush", 0600, arch_debugfs_dir, NULL, &fops_rfi_flush);
        debugfs_create_file("entry_flush", 0600, arch_debugfs_dir, NULL, &fops_entry_flush);
        debugfs_create_file("uaccess_flush", 0600, arch_debugfs_dir, NULL, &fops_uaccess_flush);
        return 0;
}
device_initcall(rfi_flush_debugfs_init);
#endif /* CONFIG_DEBUG_FS */
#endif /* CONFIG_PPC_BOOK3S_64 */