hypfs_diag.c

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/*
 *    Hypervisor filesystem for Linux on s390. Diag 204 and 224
 *    implementation.
 *
 *    Copyright IBM Corp. 2006, 2008
 *    Author(s): Michael Holzheu <[email protected]>
 */

#define KMSG_COMPONENT "hypfs"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <asm/ebcdic.h>
#include "hypfs.h"

#define LPAR_NAME_LEN 8     /* lpar name len in diag 204 data */
#define CPU_NAME_LEN 16     /* type name len of cpus in diag224 name table */
#define TMP_SIZE 64     /* size of temporary buffers */

#define DBFS_D204_HDR_VERSION   0

/* diag 204 subcodes */
enum diag204_sc {
    SUBC_STIB4 = 4,
    SUBC_RSI = 5,
    SUBC_STIB6 = 6,
    SUBC_STIB7 = 7
};

/* The two available diag 204 data formats */
enum diag204_format {
    INFO_SIMPLE = 0,
    INFO_EXT = 0x00010000
};

/* bit is set in flags, when physical cpu info is included in diag 204 data */
#define LPAR_PHYS_FLG  0x80

static char *diag224_cpu_names;         /* diag 224 name table */
static enum diag204_sc diag204_store_sc;    /* used subcode for store */
static enum diag204_format diag204_info_type;   /* used diag 204 data format */

static void *diag204_buf;       /* 4K aligned buffer for diag204 data */
static void *diag204_buf_vmalloc;   /* vmalloc pointer for diag204 data */
static int diag204_buf_pages;       /* number of pages for diag204 data */

static struct dentry *dbfs_d204_file;

/*
 * DIAG 204 data structures and member access functions.
 *
 * Since we have two different diag 204 data formats for old and new s390
 * machines, we do not access the structs directly, but use getter functions for
 * each struct member instead. This should make the code more readable.
 */

/* Time information block */

struct info_blk_hdr {
    __u8  npar;
    __u8  flags;
    __u16 tslice;
    __u16 phys_cpus;
    __u16 this_part;
    __u64 curtod;
} __attribute__ ((packed));

struct x_info_blk_hdr {
    __u8  npar;
    __u8  flags;
    __u16 tslice;
    __u16 phys_cpus;
    __u16 this_part;
    __u64 curtod1;
    __u64 curtod2;
    char reserved[40];
} __attribute__ ((packed));

static inline int info_blk_hdr__size(enum diag204_format type)
{
    if (type == INFO_SIMPLE)
        return sizeof(struct info_blk_hdr);
    else /* INFO_EXT */
        return sizeof(struct x_info_blk_hdr);
}

static inline __u8 info_blk_hdr__npar(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct info_blk_hdr *)hdr)->npar;
    else /* INFO_EXT */
        return ((struct x_info_blk_hdr *)hdr)->npar;
}

static inline __u8 info_blk_hdr__flags(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct info_blk_hdr *)hdr)->flags;
    else /* INFO_EXT */
        return ((struct x_info_blk_hdr *)hdr)->flags;
}

static inline __u16 info_blk_hdr__pcpus(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct info_blk_hdr *)hdr)->phys_cpus;
    else /* INFO_EXT */
        return ((struct x_info_blk_hdr *)hdr)->phys_cpus;
}

/* Partition header */

struct part_hdr {
    __u8 pn;
    __u8 cpus;
    char reserved[6];
    char part_name[LPAR_NAME_LEN];
} __attribute__ ((packed));

struct x_part_hdr {
    __u8  pn;
    __u8  cpus;
    __u8  rcpus;
    __u8  pflag;
    __u32 mlu;
    char  part_name[LPAR_NAME_LEN];
    char  lpc_name[8];
    char  os_name[8];
    __u64 online_cs;
    __u64 online_es;
    __u8  upid;
    char  reserved1[3];
    __u32 group_mlu;
    char  group_name[8];
    char  reserved2[32];
} __attribute__ ((packed));

static inline int part_hdr__size(enum diag204_format type)
{
    if (type == INFO_SIMPLE)
        return sizeof(struct part_hdr);
    else /* INFO_EXT */
        return sizeof(struct x_part_hdr);
}

static inline __u8 part_hdr__rcpus(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct part_hdr *)hdr)->cpus;
    else /* INFO_EXT */
        return ((struct x_part_hdr *)hdr)->rcpus;
}

static inline void part_hdr__part_name(enum diag204_format type, void *hdr,
                       char *name)
{
    if (type == INFO_SIMPLE)
        memcpy(name, ((struct part_hdr *)hdr)->part_name,
               LPAR_NAME_LEN);
    else /* INFO_EXT */
        memcpy(name, ((struct x_part_hdr *)hdr)->part_name,
               LPAR_NAME_LEN);
    EBCASC(name, LPAR_NAME_LEN);
    name[LPAR_NAME_LEN] = 0;
    strim(name);
}

struct cpu_info {
    __u16 cpu_addr;
    char  reserved1[2];
    __u8  ctidx;
    __u8  cflag;
    __u16 weight;
    __u64 acc_time;
    __u64 lp_time;
} __attribute__ ((packed));

struct x_cpu_info {
    __u16 cpu_addr;
    char  reserved1[2];
    __u8  ctidx;
    __u8  cflag;
    __u16 weight;
    __u64 acc_time;
    __u64 lp_time;
    __u16 min_weight;
    __u16 cur_weight;
    __u16 max_weight;
    char  reseved2[2];
    __u64 online_time;
    __u64 wait_time;
    __u32 pma_weight;
    __u32 polar_weight;
    char  reserved3[40];
} __attribute__ ((packed));

/* CPU info block */

static inline int cpu_info__size(enum diag204_format type)
{
    if (type == INFO_SIMPLE)
        return sizeof(struct cpu_info);
    else /* INFO_EXT */
        return sizeof(struct x_cpu_info);
}

static inline __u8 cpu_info__ctidx(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct cpu_info *)hdr)->ctidx;
    else /* INFO_EXT */
        return ((struct x_cpu_info *)hdr)->ctidx;
}

static inline __u16 cpu_info__cpu_addr(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct cpu_info *)hdr)->cpu_addr;
    else /* INFO_EXT */
        return ((struct x_cpu_info *)hdr)->cpu_addr;
}

static inline __u64 cpu_info__acc_time(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct cpu_info *)hdr)->acc_time;
    else /* INFO_EXT */
        return ((struct x_cpu_info *)hdr)->acc_time;
}

static inline __u64 cpu_info__lp_time(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct cpu_info *)hdr)->lp_time;
    else /* INFO_EXT */
        return ((struct x_cpu_info *)hdr)->lp_time;
}

static inline __u64 cpu_info__online_time(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return 0;   /* online_time not available in simple info */
    else /* INFO_EXT */
        return ((struct x_cpu_info *)hdr)->online_time;
}

/* Physical header */

struct phys_hdr {
    char reserved1[1];
    __u8 cpus;
    char reserved2[6];
    char mgm_name[8];
} __attribute__ ((packed));

struct x_phys_hdr {
    char reserved1[1];
    __u8 cpus;
    char reserved2[6];
    char mgm_name[8];
    char reserved3[80];
} __attribute__ ((packed));

static inline int phys_hdr__size(enum diag204_format type)
{
    if (type == INFO_SIMPLE)
        return sizeof(struct phys_hdr);
    else /* INFO_EXT */
        return sizeof(struct x_phys_hdr);
}

static inline __u8 phys_hdr__cpus(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct phys_hdr *)hdr)->cpus;
    else /* INFO_EXT */
        return ((struct x_phys_hdr *)hdr)->cpus;
}

/* Physical CPU info block */

struct phys_cpu {
    __u16 cpu_addr;
    char  reserved1[2];
    __u8  ctidx;
    char  reserved2[3];
    __u64 mgm_time;
    char  reserved3[8];
} __attribute__ ((packed));

struct x_phys_cpu {
    __u16 cpu_addr;
    char  reserved1[2];
    __u8  ctidx;
    char  reserved2[3];
    __u64 mgm_time;
    char  reserved3[80];
} __attribute__ ((packed));

static inline int phys_cpu__size(enum diag204_format type)
{
    if (type == INFO_SIMPLE)
        return sizeof(struct phys_cpu);
    else /* INFO_EXT */
        return sizeof(struct x_phys_cpu);
}

static inline __u16 phys_cpu__cpu_addr(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct phys_cpu *)hdr)->cpu_addr;
    else /* INFO_EXT */
        return ((struct x_phys_cpu *)hdr)->cpu_addr;
}

static inline __u64 phys_cpu__mgm_time(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct phys_cpu *)hdr)->mgm_time;
    else /* INFO_EXT */
        return ((struct x_phys_cpu *)hdr)->mgm_time;
}

static inline __u64 phys_cpu__ctidx(enum diag204_format type, void *hdr)
{
    if (type == INFO_SIMPLE)
        return ((struct phys_cpu *)hdr)->ctidx;
    else /* INFO_EXT */
        return ((struct x_phys_cpu *)hdr)->ctidx;
}

/* Diagnose 204 functions */

static int diag204(unsigned long subcode, unsigned long size, void *addr)
{
    register unsigned long _subcode asm("0") = subcode;
    register unsigned long _size asm("1") = size;

    asm volatile(
        "   diag    %2,%0,0x204\n"
        "0:\n"
        EX_TABLE(0b,0b)
        : "+d" (_subcode), "+d" (_size) : "d" (addr) : "memory");
    if (_subcode)
        return -1;
    return _size;
}

/*
 * For the old diag subcode 4 with simple data format we have to use real
 * memory. If we use subcode 6 or 7 with extended data format, we can (and
 * should) use vmalloc, since we need a lot of memory in that case. Currently
 * up to 93 pages!
 */

static void diag204_free_buffer(void)
{
    if (!diag204_buf)
        return;
    if (diag204_buf_vmalloc) {
        vfree(diag204_buf_vmalloc);
        diag204_buf_vmalloc = NULL;
    } else {
        free_pages((unsigned long) diag204_buf, 0);
    }
    diag204_buf = NULL;
}

static void *page_align_ptr(void *ptr)
{
    return (void *) PAGE_ALIGN((unsigned long) ptr);
}

static void *diag204_alloc_vbuf(int pages)
{
    /* The buffer has to be page aligned! */
    diag204_buf_vmalloc = vmalloc(PAGE_SIZE * (pages + 1));
    if (!diag204_buf_vmalloc)
        return ERR_PTR(-ENOMEM);
    diag204_buf = page_align_ptr(diag204_buf_vmalloc);
    diag204_buf_pages = pages;
    return diag204_buf;
}

static void *diag204_alloc_rbuf(void)
{
    diag204_buf = (void*)__get_free_pages(GFP_KERNEL,0);
    if (!diag204_buf)
        return ERR_PTR(-ENOMEM);
    diag204_buf_pages = 1;
    return diag204_buf;
}

static void *diag204_get_buffer(enum diag204_format fmt, int *pages)
{
    if (diag204_buf) {
        *pages = diag204_buf_pages;
        return diag204_buf;
    }
    if (fmt == INFO_SIMPLE) {
        *pages = 1;
        return diag204_alloc_rbuf();
    } else {/* INFO_EXT */
        *pages = diag204((unsigned long)SUBC_RSI |
                 (unsigned long)INFO_EXT, 0, NULL);
        if (*pages <= 0)
            return ERR_PTR(-ENOSYS);
        else
            return diag204_alloc_vbuf(*pages);
    }
}

/*
 * diag204_probe() has to find out, which type of diagnose 204 implementation
 * we have on our machine. Currently there are three possible scanarios:
 *   - subcode 4   + simple data format (only one page)
 *   - subcode 4-6 + extended data format
 *   - subcode 4-7 + extended data format
 *
 * Subcode 5 is used to retrieve the size of the data, provided by subcodes
 * 6 and 7. Subcode 7 basically has the same function as subcode 6. In addition
 * to subcode 6 it provides also information about secondary cpus.
 * In order to get as much information as possible, we first try
 * subcode 7, then 6 and if both fail, we use subcode 4.
 */

static int diag204_probe(void)
{
    void *buf;
    int pages, rc;

    buf = diag204_get_buffer(INFO_EXT, &pages);
    if (!IS_ERR(buf)) {
        if (diag204((unsigned long)SUBC_STIB7 |
                (unsigned long)INFO_EXT, pages, buf) >= 0) {
            diag204_store_sc = SUBC_STIB7;
            diag204_info_type = INFO_EXT;
            goto out;
        }
        if (diag204((unsigned long)SUBC_STIB6 |
                (unsigned long)INFO_EXT, pages, buf) >= 0) {
            diag204_store_sc = SUBC_STIB6;
            diag204_info_type = INFO_EXT;
            goto out;
        }
        diag204_free_buffer();
    }

    /* subcodes 6 and 7 failed, now try subcode 4 */

    buf = diag204_get_buffer(INFO_SIMPLE, &pages);
    if (IS_ERR(buf)) {
        rc = PTR_ERR(buf);
        goto fail_alloc;
    }
    if (diag204((unsigned long)SUBC_STIB4 |
            (unsigned long)INFO_SIMPLE, pages, buf) >= 0) {
        diag204_store_sc = SUBC_STIB4;
        diag204_info_type = INFO_SIMPLE;
        goto out;
    } else {
        rc = -ENOSYS;
        goto fail_store;
    }
out:
    rc = 0;
fail_store:
    diag204_free_buffer();
fail_alloc:
    return rc;
}

static int diag204_do_store(void *buf, int pages)
{
    int rc;

    rc = diag204((unsigned long) diag204_store_sc |
             (unsigned long) diag204_info_type, pages, buf);
    return rc < 0 ? -ENOSYS : 0;
}

static void *diag204_store(void)
{
    void *buf;
    int pages, rc;

    buf = diag204_get_buffer(diag204_info_type, &pages);
    if (IS_ERR(buf))
        goto out;
    rc = diag204_do_store(buf, pages);
    if (rc)
        return ERR_PTR(rc);
out:
    return buf;
}

/* Diagnose 224 functions */

static int diag224(void *ptr)
{
    int rc = -EOPNOTSUPP;

    asm volatile(
        "   diag    %1,%2,0x224\n"
        "0: lhi %0,0x0\n"
        "1:\n"
        EX_TABLE(0b,1b)
        : "+d" (rc) :"d" (0), "d" (ptr) : "memory");
    return rc;
}

static int diag224_get_name_table(void)
{
    /* memory must be below 2GB */
    diag224_cpu_names = kmalloc(PAGE_SIZE, GFP_KERNEL | GFP_DMA);
    if (!diag224_cpu_names)
        return -ENOMEM;
    if (diag224(diag224_cpu_names)) {
        kfree(diag224_cpu_names);
        return -EOPNOTSUPP;
    }
    EBCASC(diag224_cpu_names + 16, (*diag224_cpu_names + 1) * 16);
    return 0;
}

static void diag224_delete_name_table(void)
{
    kfree(diag224_cpu_names);
}

static int diag224_idx2name(int index, char *name)
{
    memcpy(name, diag224_cpu_names + ((index + 1) * CPU_NAME_LEN),
        CPU_NAME_LEN);
    name[CPU_NAME_LEN] = 0;
    strim(name);
    return 0;
}

struct dbfs_d204_hdr {
    u64 len;        /* Length of d204 buffer without header */
    u16 version;    /* Version of header */
    u8  sc;     /* Used subcode */
    char    reserved[53];
} __attribute__ ((packed));

struct dbfs_d204 {
    struct dbfs_d204_hdr    hdr;    /* 64 byte header */
    char            buf[];  /* d204 buffer */
} __attribute__ ((packed));

static int dbfs_d204_create(void **data, void **data_free_ptr, size_t *size)
{
    struct dbfs_d204 *d204;
    int rc, buf_size;
    void *base;

    buf_size = PAGE_SIZE * (diag204_buf_pages + 1) + sizeof(d204->hdr);
    base = vzalloc(buf_size);
    if (!base)
        return -ENOMEM;
    d204 = page_align_ptr(base + sizeof(d204->hdr)) - sizeof(d204->hdr);
    rc = diag204_do_store(d204->buf, diag204_buf_pages);
    if (rc) {
        vfree(base);
        return rc;
    }
    d204->hdr.version = DBFS_D204_HDR_VERSION;
    d204->hdr.len = PAGE_SIZE * diag204_buf_pages;
    d204->hdr.sc = diag204_store_sc;
    *data = d204;
    *data_free_ptr = base;
    *size = d204->hdr.len + sizeof(struct dbfs_d204_hdr);
    return 0;
}

static struct hypfs_dbfs_file dbfs_file_d204 = {
    .name       = "diag_204",
    .data_create    = dbfs_d204_create,
    .data_free  = vfree,
};

__init int hypfs_diag_init(void)
{
    int rc;

    if (diag204_probe()) {
        pr_err("The hardware system does not support hypfs\n");
        return -ENODATA;
    }
    if (diag204_info_type == INFO_EXT) {
        rc = hypfs_dbfs_create_file(&dbfs_file_d204);
        if (rc)
            return rc;
    }
    if (MACHINE_IS_LPAR) {
        rc = diag224_get_name_table();
        if (rc) {
            pr_err("The hardware system does not provide all "
                   "functions required by hypfs\n");
            debugfs_remove(dbfs_d204_file);
            return rc;
        }
    }
    return 0;
}

void hypfs_diag_exit(void)
{
    debugfs_remove(dbfs_d204_file);
    diag224_delete_name_table();
    diag204_free_buffer();
    hypfs_dbfs_remove_file(&dbfs_file_d204);
}

/*
 * Functions to create the directory structure
 * *******************************************
 */

static int hypfs_create_cpu_files(struct super_block *sb,
                  struct dentry *cpus_dir, void *cpu_info)
{
    struct dentry *cpu_dir;
    char buffer[TMP_SIZE];
    void *rc;

    snprintf(buffer, TMP_SIZE, "%d", cpu_info__cpu_addr(diag204_info_type,
                                cpu_info));
    cpu_dir = hypfs_mkdir(sb, cpus_dir, buffer);
    rc = hypfs_create_u64(sb, cpu_dir, "mgmtime",
                  cpu_info__acc_time(diag204_info_type, cpu_info) -
                  cpu_info__lp_time(diag204_info_type, cpu_info));
    if (IS_ERR(rc))
        return PTR_ERR(rc);
    rc = hypfs_create_u64(sb, cpu_dir, "cputime",
                  cpu_info__lp_time(diag204_info_type, cpu_info));
    if (IS_ERR(rc))
        return PTR_ERR(rc);
    if (diag204_info_type == INFO_EXT) {
        rc = hypfs_create_u64(sb, cpu_dir, "onlinetime",
                      cpu_info__online_time(diag204_info_type,
                                cpu_info));
        if (IS_ERR(rc))
            return PTR_ERR(rc);
    }
    diag224_idx2name(cpu_info__ctidx(diag204_info_type, cpu_info), buffer);
    rc = hypfs_create_str(sb, cpu_dir, "type", buffer);
    if (IS_ERR(rc))
        return PTR_ERR(rc);
    return 0;
}

static void *hypfs_create_lpar_files(struct super_block *sb,
                     struct dentry *systems_dir, void *part_hdr)
{
    struct dentry *cpus_dir;
    struct dentry *lpar_dir;
    char lpar_name[LPAR_NAME_LEN + 1];
    void *cpu_info;
    int i;

    part_hdr__part_name(diag204_info_type, part_hdr, lpar_name);
    lpar_name[LPAR_NAME_LEN] = 0;
    lpar_dir = hypfs_mkdir(sb, systems_dir, lpar_name);
    if (IS_ERR(lpar_dir))
        return lpar_dir;
    cpus_dir = hypfs_mkdir(sb, lpar_dir, "cpus");
    if (IS_ERR(cpus_dir))
        return cpus_dir;
    cpu_info = part_hdr + part_hdr__size(diag204_info_type);
    for (i = 0; i < part_hdr__rcpus(diag204_info_type, part_hdr); i++) {
        int rc;
        rc = hypfs_create_cpu_files(sb, cpus_dir, cpu_info);
        if (rc)
            return ERR_PTR(rc);
        cpu_info += cpu_info__size(diag204_info_type);
    }
    return cpu_info;
}

static int hypfs_create_phys_cpu_files(struct super_block *sb,
                       struct dentry *cpus_dir, void *cpu_info)
{
    struct dentry *cpu_dir;
    char buffer[TMP_SIZE];
    void *rc;

    snprintf(buffer, TMP_SIZE, "%i", phys_cpu__cpu_addr(diag204_info_type,
                                cpu_info));
    cpu_dir = hypfs_mkdir(sb, cpus_dir, buffer);
    if (IS_ERR(cpu_dir))
        return PTR_ERR(cpu_dir);
    rc = hypfs_create_u64(sb, cpu_dir, "mgmtime",
                  phys_cpu__mgm_time(diag204_info_type, cpu_info));
    if (IS_ERR(rc))
        return PTR_ERR(rc);
    diag224_idx2name(phys_cpu__ctidx(diag204_info_type, cpu_info), buffer);
    rc = hypfs_create_str(sb, cpu_dir, "type", buffer);
    if (IS_ERR(rc))
        return PTR_ERR(rc);
    return 0;
}

static void *hypfs_create_phys_files(struct super_block *sb,
                     struct dentry *parent_dir, void *phys_hdr)
{
    int i;
    void *cpu_info;
    struct dentry *cpus_dir;

    cpus_dir = hypfs_mkdir(sb, parent_dir, "cpus");
    if (IS_ERR(cpus_dir))
        return cpus_dir;
    cpu_info = phys_hdr + phys_hdr__size(diag204_info_type);
    for (i = 0; i < phys_hdr__cpus(diag204_info_type, phys_hdr); i++) {
        int rc;
        rc = hypfs_create_phys_cpu_files(sb, cpus_dir, cpu_info);
        if (rc)
            return ERR_PTR(rc);
        cpu_info += phys_cpu__size(diag204_info_type);
    }
    return cpu_info;
}

int hypfs_diag_create_files(struct super_block *sb, struct dentry *root)
{
    struct dentry *systems_dir, *hyp_dir;
    void *time_hdr, *part_hdr;
    int i, rc;
    void *buffer, *ptr;

    buffer = diag204_store();
    if (IS_ERR(buffer))
        return PTR_ERR(buffer);

    systems_dir = hypfs_mkdir(sb, root, "systems");
    if (IS_ERR(systems_dir)) {
        rc = PTR_ERR(systems_dir);
        goto err_out;
    }
    time_hdr = (struct x_info_blk_hdr *)buffer;
    part_hdr = time_hdr + info_blk_hdr__size(diag204_info_type);
    for (i = 0; i < info_blk_hdr__npar(diag204_info_type, time_hdr); i++) {
        part_hdr = hypfs_create_lpar_files(sb, systems_dir, part_hdr);
        if (IS_ERR(part_hdr)) {
            rc = PTR_ERR(part_hdr);
            goto err_out;
        }
    }
    if (info_blk_hdr__flags(diag204_info_type, time_hdr) & LPAR_PHYS_FLG) {
        ptr = hypfs_create_phys_files(sb, root, part_hdr);
        if (IS_ERR(ptr)) {
            rc = PTR_ERR(ptr);
            goto err_out;
        }
    }
    hyp_dir = hypfs_mkdir(sb, root, "hyp");
    if (IS_ERR(hyp_dir)) {
        rc = PTR_ERR(hyp_dir);
        goto err_out;
    }
    ptr = hypfs_create_str(sb, hyp_dir, "type", "LPAR Hypervisor");
    if (IS_ERR(ptr)) {
        rc = PTR_ERR(ptr);
        goto err_out;
    }
    rc = 0;

err_out:
    return rc;
}