// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/arch/alpha/kernel/osf_sys.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 */

/*
 * This file handles some of the stranger OSF/1 system call interfaces.
 * Some of the system calls expect a non-C calling standard, others have
 * special parameter blocks..
 */

#include <linux/errno.h>
#include <linux/sched/signal.h>
#include <linux/sched/mm.h>
#include <linux/sched/task_stack.h>
#include <linux/sched/cputime.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/stddef.h>
#include <linux/syscalls.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/utsname.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/major.h>
#include <linux/stat.h>
#include <linux/mman.h>
#include <linux/shm.h>
#include <linux/poll.h>
#include <linux/file.h>
#include <linux/types.h>
#include <linux/ipc.h>
#include <linux/namei.h>
#include <linux/uio.h>
#include <linux/vfs.h>
#include <linux/rcupdate.h>
#include <linux/slab.h>

#include <asm/fpu.h>
#include <asm/io.h>
#include <linux/uaccess.h>
#include <asm/sysinfo.h>
#include <asm/thread_info.h>
#include <asm/hwrpb.h>
#include <asm/processor.h>

/*
 * Brk needs to return an error.  Still support Linux's brk(0) query idiom,
 * which OSF programs just shouldn't be doing.  We're still not quite
 * identical to OSF as we don't return 0 on success, but doing otherwise
 * would require changes to libc.  Hopefully this is good enough.
 */
SYSCALL_DEFINE1(osf_brk, unsigned long, brk)
{
        unsigned long retval = sys_brk(brk);
        if (brk && brk != retval)
                retval = -ENOMEM;
        return retval;
}
 
/*
 * This is pure guess-work..
 */
SYSCALL_DEFINE4(osf_set_program_attributes, unsigned long, text_start,
                unsigned long, text_len, unsigned long, bss_start,
                unsigned long, bss_len)
{
        struct mm_struct *mm;

        mm = current->mm;
        mm->end_code = bss_start + bss_len;
        mm->start_brk = bss_start + bss_len;
        mm->brk = bss_start + bss_len;
#if 0
        printk("set_program_attributes(%lx %lx %lx %lx)\n",
                text_start, text_len, bss_start, bss_len);
#endif
        return 0;
}

/*
 * OSF/1 directory handling functions...
 *
 * The "getdents()" interface is much more sane: the "basep" stuff is
 * braindamage (it can't really handle filesystems where the directory
 * offset differences aren't the same as "d_reclen").
 */
#define NAME_OFFSET     offsetof (struct osf_dirent, d_name)

struct osf_dirent {
        unsigned int d_ino;
        unsigned short d_reclen;
        unsigned short d_namlen;
        char d_name[1];
};

struct osf_dirent_callback {
        struct dir_context ctx;
        struct osf_dirent __user *dirent;
        long __user *basep;
        unsigned int count;
        int error;
};

static int
osf_filldir(struct dir_context *ctx, const char *name, int namlen,
            loff_t offset, u64 ino, unsigned int d_type)
{
        struct osf_dirent __user *dirent;
        struct osf_dirent_callback *buf =
                container_of(ctx, struct osf_dirent_callback, ctx);
        unsigned int reclen = ALIGN(NAME_OFFSET + namlen + 1, sizeof(u32));
        unsigned int d_ino;

        buf->error = -EINVAL;   /* only used if we fail */
        if (reclen > buf->count)
                return -EINVAL;
        d_ino = ino;
        if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
                buf->error = -EOVERFLOW;
                return -EOVERFLOW;
        }
        if (buf->basep) {
                if (put_user(offset, buf->basep))
                        goto Efault;
                buf->basep = NULL;
        }
        dirent = buf->dirent;
        if (put_user(d_ino, &dirent->d_ino) ||
            put_user(namlen, &dirent->d_namlen) ||
            put_user(reclen, &dirent->d_reclen) ||
            copy_to_user(dirent->d_name, name, namlen) ||
            put_user(0, dirent->d_name + namlen))
                goto Efault;
        dirent = (void __user *)dirent + reclen;
        buf->dirent = dirent;
        buf->count -= reclen;
        return 0;
Efault:
        buf->error = -EFAULT;
        return -EFAULT;
}

SYSCALL_DEFINE4(osf_getdirentries, unsigned int, fd,
                struct osf_dirent __user *, dirent, unsigned int, count,
                long __user *, basep)
{
        int error;
        struct fd arg = fdget_pos(fd);
        struct osf_dirent_callback buf = {
                .ctx.actor = osf_filldir,
                .dirent = dirent,
                .basep = basep,
                .count = count
        };

        if (!arg.file)
                return -EBADF;

        error = iterate_dir(arg.file, &buf.ctx);
        if (error >= 0)
                error = buf.error;
        if (count != buf.count)
                error = count - buf.count;

        fdput_pos(arg);
        return error;
}

#undef NAME_OFFSET

SYSCALL_DEFINE6(osf_mmap, unsigned long, addr, unsigned long, len,
                unsigned long, prot, unsigned long, flags, unsigned long, fd,
                unsigned long, off)
{
        unsigned long ret = -EINVAL;

#if 0
        if (flags & (_MAP_HASSEMAPHORE | _MAP_INHERIT | _MAP_UNALIGNED))
                printk("%s: unimplemented OSF mmap flags %04lx\n", 
                        current->comm, flags);
#endif
        if ((off + PAGE_ALIGN(len)) < off)
                goto out;
        if (off & ~PAGE_MASK)
                goto out;
        ret = ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 out:
        return ret;
}

struct osf_stat {
        int             st_dev;
        int             st_pad1;
        unsigned        st_mode;
        unsigned short  st_nlink;
        short           st_nlink_reserved;
        unsigned        st_uid;
        unsigned        st_gid;
        int             st_rdev;
        int             st_ldev;
        long            st_size;
        int             st_pad2;
        int             st_uatime;
        int             st_pad3;
        int             st_umtime;
        int             st_pad4;
        int             st_uctime;
        int             st_pad5;
        int             st_pad6;
        unsigned        st_flags;
        unsigned        st_gen;
        long            st_spare[4];
        unsigned        st_ino;
        int             st_ino_reserved;
        int             st_atime;
        int             st_atime_reserved;
        int             st_mtime;
        int             st_mtime_reserved;
        int             st_ctime;
        int             st_ctime_reserved;
        long            st_blksize;
        long            st_blocks;
};

/*
 * The OSF/1 statfs structure is much larger, but this should
 * match the beginning, at least.
 */
struct osf_statfs {
        short f_type;
        short f_flags;
        int f_fsize;
        int f_bsize;
        int f_blocks;
        int f_bfree;
        int f_bavail;
        int f_files;
        int f_ffree;
        __kernel_fsid_t f_fsid;
};

struct osf_statfs64 {
        short f_type;
        short f_flags;
        int f_pad1;
        int f_pad2;
        int f_pad3;
        int f_pad4;
        int f_pad5;
        int f_pad6;
        int f_pad7;
        __kernel_fsid_t f_fsid;
        u_short f_namemax;
        short f_reserved1;
        int f_spare[8];
        char f_pad8[90];
        char f_pad9[90];
        long mount_info[10];
        u_long f_flags2;
        long f_spare2[14];
        long f_fsize;
        long f_bsize;
        long f_blocks;
        long f_bfree;
        long f_bavail;
        long f_files;
        long f_ffree;
};

static int
linux_to_osf_stat(struct kstat *lstat, struct osf_stat __user *osf_stat)
{
        struct osf_stat tmp = { 0 };

        tmp.st_dev      = lstat->dev;
        tmp.st_mode     = lstat->mode;
        tmp.st_nlink    = lstat->nlink;
        tmp.st_uid      = from_kuid_munged(current_user_ns(), lstat->uid);
        tmp.st_gid      = from_kgid_munged(current_user_ns(), lstat->gid);
        tmp.st_rdev     = lstat->rdev;
        tmp.st_ldev     = lstat->rdev;
        tmp.st_size     = lstat->size;
        tmp.st_uatime   = lstat->atime.tv_nsec / 1000;
        tmp.st_umtime   = lstat->mtime.tv_nsec / 1000;
        tmp.st_uctime   = lstat->ctime.tv_nsec / 1000;
        tmp.st_ino      = lstat->ino;
        tmp.st_atime    = lstat->atime.tv_sec;
        tmp.st_mtime    = lstat->mtime.tv_sec;
        tmp.st_ctime    = lstat->ctime.tv_sec;
        tmp.st_blksize  = lstat->blksize;
        tmp.st_blocks   = lstat->blocks;

        return copy_to_user(osf_stat, &tmp, sizeof(tmp)) ? -EFAULT : 0;
}

static int
linux_to_osf_statfs(struct kstatfs *linux_stat, struct osf_statfs __user *osf_stat,
                    unsigned long bufsiz)
{
        struct osf_statfs tmp_stat;

        tmp_stat.f_type = linux_stat->f_type;
        tmp_stat.f_flags = 0;   /* mount flags */
        tmp_stat.f_fsize = linux_stat->f_frsize;
        tmp_stat.f_bsize = linux_stat->f_bsize;
        tmp_stat.f_blocks = linux_stat->f_blocks;
        tmp_stat.f_bfree = linux_stat->f_bfree;
        tmp_stat.f_bavail = linux_stat->f_bavail;
        tmp_stat.f_files = linux_stat->f_files;
        tmp_stat.f_ffree = linux_stat->f_ffree;
        tmp_stat.f_fsid = linux_stat->f_fsid;
        if (bufsiz > sizeof(tmp_stat))
                bufsiz = sizeof(tmp_stat);
        return copy_to_user(osf_stat, &tmp_stat, bufsiz) ? -EFAULT : 0;
}

static int
linux_to_osf_statfs64(struct kstatfs *linux_stat, struct osf_statfs64 __user *osf_stat,
                      unsigned long bufsiz)
{
        struct osf_statfs64 tmp_stat = { 0 };

        tmp_stat.f_type = linux_stat->f_type;
        tmp_stat.f_fsize = linux_stat->f_frsize;
        tmp_stat.f_bsize = linux_stat->f_bsize;
        tmp_stat.f_blocks = linux_stat->f_blocks;
        tmp_stat.f_bfree = linux_stat->f_bfree;
        tmp_stat.f_bavail = linux_stat->f_bavail;
        tmp_stat.f_files = linux_stat->f_files;
        tmp_stat.f_ffree = linux_stat->f_ffree;
        tmp_stat.f_fsid = linux_stat->f_fsid;
        if (bufsiz > sizeof(tmp_stat))
                bufsiz = sizeof(tmp_stat);
        return copy_to_user(osf_stat, &tmp_stat, bufsiz) ? -EFAULT : 0;
}

SYSCALL_DEFINE3(osf_statfs, const char __user *, pathname,
                struct osf_statfs __user *, buffer, unsigned long, bufsiz)
{
        struct kstatfs linux_stat;
        int error = user_statfs(pathname, &linux_stat);
        if (!error)
                error = linux_to_osf_statfs(&linux_stat, buffer, bufsiz);
        return error;   
}

SYSCALL_DEFINE2(osf_stat, char __user *, name, struct osf_stat __user *, buf)
{
        struct kstat stat;
        int error;

        error = vfs_stat(name, &stat);
        if (error)
                return error;

        return linux_to_osf_stat(&stat, buf);
}

SYSCALL_DEFINE2(osf_lstat, char __user *, name, struct osf_stat __user *, buf)
{
        struct kstat stat;
        int error;

        error = vfs_lstat(name, &stat);
        if (error)
                return error;

        return linux_to_osf_stat(&stat, buf);
}

SYSCALL_DEFINE2(osf_fstat, int, fd, struct osf_stat __user *, buf)
{
        struct kstat stat;
        int error;

        error = vfs_fstat(fd, &stat);
        if (error)
                return error;

        return linux_to_osf_stat(&stat, buf);
}

SYSCALL_DEFINE3(osf_fstatfs, unsigned long, fd,
                struct osf_statfs __user *, buffer, unsigned long, bufsiz)
{
        struct kstatfs linux_stat;
        int error = fd_statfs(fd, &linux_stat);
        if (!error)
                error = linux_to_osf_statfs(&linux_stat, buffer, bufsiz);
        return error;
}

SYSCALL_DEFINE3(osf_statfs64, char __user *, pathname,
                struct osf_statfs64 __user *, buffer, unsigned long, bufsiz)
{
        struct kstatfs linux_stat;
        int error = user_statfs(pathname, &linux_stat);
        if (!error)
                error = linux_to_osf_statfs64(&linux_stat, buffer, bufsiz);
        return error;
}

SYSCALL_DEFINE3(osf_fstatfs64, unsigned long, fd,
                struct osf_statfs64 __user *, buffer, unsigned long, bufsiz)
{
        struct kstatfs linux_stat;
        int error = fd_statfs(fd, &linux_stat);
        if (!error)
                error = linux_to_osf_statfs64(&linux_stat, buffer, bufsiz);
        return error;
}

/*
 * Uhh.. OSF/1 mount parameters aren't exactly obvious..
 *
 * Although to be frank, neither are the native Linux/i386 ones..
 */
struct ufs_args {
        char __user *devname;
        int flags;
        uid_t exroot;
};

struct cdfs_args {
        char __user *devname;
        int flags;
        uid_t exroot;

        /* This has lots more here, which Linux handles with the option block
           but I'm too lazy to do the translation into ASCII.  */
};

struct procfs_args {
        char __user *devname;
        int flags;
        uid_t exroot;
};

/*
 * We can't actually handle ufs yet, so we translate UFS mounts to
 * ext2fs mounts. I wouldn't mind a UFS filesystem, but the UFS
 * layout is so braindead it's a major headache doing it.
 *
 * Just how long ago was it written? OTOH our UFS driver may be still
 * unhappy with OSF UFS. [CHECKME]
 */
static int
osf_ufs_mount(const char __user *dirname,
              struct ufs_args __user *args, int flags)
{
        int retval;
        struct cdfs_args tmp;
        struct filename *devname;

        retval = -EFAULT;
        if (copy_from_user(&tmp, args, sizeof(tmp)))
                goto out;
        devname = getname(tmp.devname);
        retval = PTR_ERR(devname);
        if (IS_ERR(devname))
                goto out;
        retval = do_mount(devname->name, dirname, "ext2", flags, NULL);
        putname(devname);
 out:
        return retval;
}

static int
osf_cdfs_mount(const char __user *dirname,
               struct cdfs_args __user *args, int flags)
{
        int retval;
        struct cdfs_args tmp;
        struct filename *devname;

        retval = -EFAULT;
        if (copy_from_user(&tmp, args, sizeof(tmp)))
                goto out;
        devname = getname(tmp.devname);
        retval = PTR_ERR(devname);
        if (IS_ERR(devname))
                goto out;
        retval = do_mount(devname->name, dirname, "iso9660", flags, NULL);
        putname(devname);
 out:
        return retval;
}

static int
osf_procfs_mount(const char __user *dirname,
                 struct procfs_args __user *args, int flags)
{
        struct procfs_args tmp;

        if (copy_from_user(&tmp, args, sizeof(tmp)))
                return -EFAULT;

        return do_mount("", dirname, "proc", flags, NULL);
}

SYSCALL_DEFINE4(osf_mount, unsigned long, typenr, const char __user *, path,
                int, flag, void __user *, data)
{
        int retval;

        switch (typenr) {
        case 1:
                retval = osf_ufs_mount(path, data, flag);
                break;
        case 6:
                retval = osf_cdfs_mount(path, data, flag);
                break;
        case 9:
                retval = osf_procfs_mount(path, data, flag);
                break;
        default:
                retval = -EINVAL;
                printk("osf_mount(%ld, %x)\n", typenr, flag);
        }

        return retval;
}

SYSCALL_DEFINE1(osf_utsname, char __user *, name)
{
        int error;

        down_read(&uts_sem);
        error = -EFAULT;
        if (copy_to_user(name + 0, utsname()->sysname, 32))
                goto out;
        if (copy_to_user(name + 32, utsname()->nodename, 32))
                goto out;
        if (copy_to_user(name + 64, utsname()->release, 32))
                goto out;
        if (copy_to_user(name + 96, utsname()->version, 32))
                goto out;
        if (copy_to_user(name + 128, utsname()->machine, 32))
                goto out;

        error = 0;
 out:
        up_read(&uts_sem);      
        return error;
}

SYSCALL_DEFINE0(getpagesize)
{
        return PAGE_SIZE;
}

SYSCALL_DEFINE0(getdtablesize)
{
        return sysctl_nr_open;
}

/*
 * For compatibility with OSF/1 only.  Use utsname(2) instead.
 */
SYSCALL_DEFINE2(osf_getdomainname, char __user *, name, int, namelen)
{
        int len, err = 0;
        char *kname;

        if (namelen > 32)
                namelen = 32;

        down_read(&uts_sem);
        kname = utsname()->domainname;
        len = strnlen(kname, namelen);
        if (copy_to_user(name, kname, min(len + 1, namelen)))
                err = -EFAULT;
        up_read(&uts_sem);

        return err;
}

/*
 * The following stuff should move into a header file should it ever
 * be labeled "officially supported."  Right now, there is just enough
 * support to avoid applications (such as tar) printing error
 * messages.  The attributes are not really implemented.
 */

/*
 * Values for Property list entry flag
 */
#define PLE_PROPAGATE_ON_COPY           0x1     /* cp(1) will copy entry
                                                   by default */
#define PLE_FLAG_MASK                   0x1     /* Valid flag values */
#define PLE_FLAG_ALL                    -1      /* All flag value */

struct proplistname_args {
        unsigned int pl_mask;
        unsigned int pl_numnames;
        char **pl_names;
};

union pl_args {
        struct setargs {
                char __user *path;
                long follow;
                long nbytes;
                char __user *buf;
        } set;
        struct fsetargs {
                long fd;
                long nbytes;
                char __user *buf;
        } fset;
        struct getargs {
                char __user *path;
                long follow;
                struct proplistname_args __user *name_args;
                long nbytes;
                char __user *buf;
                int __user *min_buf_size;
        } get;
        struct fgetargs {
                long fd;
                struct proplistname_args __user *name_args;
                long nbytes;
                char __user *buf;
                int __user *min_buf_size;
        } fget;
        struct delargs {
                char __user *path;
                long follow;
                struct proplistname_args __user *name_args;
        } del;
        struct fdelargs {
                long fd;
                struct proplistname_args __user *name_args;
        } fdel;
};

enum pl_code {
        PL_SET = 1, PL_FSET = 2,
        PL_GET = 3, PL_FGET = 4,
        PL_DEL = 5, PL_FDEL = 6
};

SYSCALL_DEFINE2(osf_proplist_syscall, enum pl_code, code,
                union pl_args __user *, args)
{
        long error;
        int __user *min_buf_size_ptr;

        switch (code) {
        case PL_SET:
                if (get_user(error, &args->set.nbytes))
                        error = -EFAULT;
                break;
        case PL_FSET:
                if (get_user(error, &args->fset.nbytes))
                        error = -EFAULT;
                break;
        case PL_GET:
                error = get_user(min_buf_size_ptr, &args->get.min_buf_size);
                if (error)
                        break;
                error = put_user(0, min_buf_size_ptr);
                break;
        case PL_FGET:
                error = get_user(min_buf_size_ptr, &args->fget.min_buf_size);
                if (error)
                        break;
                error = put_user(0, min_buf_size_ptr);
                break;
        case PL_DEL:
        case PL_FDEL:
                error = 0;
                break;
        default:
                error = -EOPNOTSUPP;
                break;
        };
        return error;
}

SYSCALL_DEFINE2(osf_sigstack, struct sigstack __user *, uss,
                struct sigstack __user *, uoss)
{
        unsigned long usp = rdusp();
        unsigned long oss_sp = current->sas_ss_sp + current->sas_ss_size;
        unsigned long oss_os = on_sig_stack(usp);
        int error;

        if (uss) {
                void __user *ss_sp;

                error = -EFAULT;
                if (get_user(ss_sp, &uss->ss_sp))
                        goto out;

                /* If the current stack was set with sigaltstack, don't
                   swap stacks while we are on it.  */
                error = -EPERM;
                if (current->sas_ss_sp && on_sig_stack(usp))
                        goto out;

                /* Since we don't know the extent of the stack, and we don't
                   track onstack-ness, but rather calculate it, we must 
                   presume a size.  Ho hum this interface is lossy.  */
                current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
                current->sas_ss_size = SIGSTKSZ;
        }

        if (uoss) {
                error = -EFAULT;
                if (put_user(oss_sp, &uoss->ss_sp) ||
                    put_user(oss_os, &uoss->ss_onstack))
                        goto out;
        }

        error = 0;
 out:
        return error;
}

SYSCALL_DEFINE3(osf_sysinfo, int, command, char __user *, buf, long, count)
{
        const char *sysinfo_table[] = {
                utsname()->sysname,
                utsname()->nodename,
                utsname()->release,
                utsname()->version,
                utsname()->machine,
                "alpha",        /* instruction set architecture */
                "dummy",        /* hardware serial number */
                "dummy",        /* hardware manufacturer */
                "dummy",        /* secure RPC domain */
        };
        unsigned long offset;
        const char *res;
        long len, err = -EINVAL;

        offset = command-1;
        if (offset >= ARRAY_SIZE(sysinfo_table)) {
                /* Digital UNIX has a few unpublished interfaces here */
                printk("sysinfo(%d)", command);
                goto out;
        }

        down_read(&uts_sem);
        res = sysinfo_table[offset];
        len = strlen(res)+1;
        if ((unsigned long)len > (unsigned long)count)
                len = count;
        if (copy_to_user(buf, res, len))
                err = -EFAULT;
        else
                err = 0;
        up_read(&uts_sem);
 out:
        return err;
}

SYSCALL_DEFINE5(osf_getsysinfo, unsigned long, op, void __user *, buffer,
                unsigned long, nbytes, int __user *, start, void __user *, arg)
{
        unsigned long w;
        struct percpu_struct *cpu;

        switch (op) {
        case GSI_IEEE_FP_CONTROL:
                /* Return current software fp control & status bits.  */
                /* Note that DU doesn't verify available space here.  */

                w = current_thread_info()->ieee_state & IEEE_SW_MASK;
                w = swcr_update_status(w, rdfpcr());
                if (put_user(w, (unsigned long __user *) buffer))
                        return -EFAULT;
                return 0;

        case GSI_IEEE_STATE_AT_SIGNAL:
                /*
                 * Not sure anybody will ever use this weird stuff.  These
                 * ops can be used (under OSF/1) to set the fpcr that should
                 * be used when a signal handler starts executing.
                 */
                break;

        case GSI_UACPROC:
                if (nbytes < sizeof(unsigned int))
                        return -EINVAL;
                w = current_thread_info()->status & UAC_BITMASK;
                if (put_user(w, (unsigned int __user *)buffer))
                        return -EFAULT;
                return 1;

        case GSI_PROC_TYPE:
                if (nbytes < sizeof(unsigned long))
                        return -EINVAL;
                cpu = (struct percpu_struct*)
                  ((char*)hwrpb + hwrpb->processor_offset);
                w = cpu->type;
                if (put_user(w, (unsigned long  __user*)buffer))
                        return -EFAULT;
                return 1;

        case GSI_GET_HWRPB:
                if (nbytes > sizeof(*hwrpb))
                        return -EINVAL;
                if (copy_to_user(buffer, hwrpb, nbytes) != 0)
                        return -EFAULT;
                return 1;

        default:
                break;
        }

        return -EOPNOTSUPP;
}

SYSCALL_DEFINE5(osf_setsysinfo, unsigned long, op, void __user *, buffer,
                unsigned long, nbytes, int __user *, start, void __user *, arg)
{
        switch (op) {
        case SSI_IEEE_FP_CONTROL: {
                unsigned long swcr, fpcr;
                unsigned int *state;

                /* 
                 * Alpha Architecture Handbook 4.7.7.3:
                 * To be fully IEEE compiant, we must track the current IEEE
                 * exception state in software, because spurious bits can be
                 * set in the trap shadow of a software-complete insn.
                 */

                if (get_user(swcr, (unsigned long __user *)buffer))
                        return -EFAULT;
                state = &current_thread_info()->ieee_state;

                /* Update softare trap enable bits.  */
                *state = (*state & ~IEEE_SW_MASK) | (swcr & IEEE_SW_MASK);

                /* Update the real fpcr.  */
                fpcr = rdfpcr() & FPCR_DYN_MASK;
                fpcr |= ieee_swcr_to_fpcr(swcr);
                wrfpcr(fpcr);

                return 0;
        }

        case SSI_IEEE_RAISE_EXCEPTION: {
                unsigned long exc, swcr, fpcr, fex;
                unsigned int *state;

                if (get_user(exc, (unsigned long __user *)buffer))
                        return -EFAULT;
                state = &current_thread_info()->ieee_state;
                exc &= IEEE_STATUS_MASK;

                /* Update softare trap enable bits.  */
                swcr = (*state & IEEE_SW_MASK) | exc;
                *state |= exc;

                /* Update the real fpcr.  */
                fpcr = rdfpcr();
                fpcr |= ieee_swcr_to_fpcr(swcr);
                wrfpcr(fpcr);

                /* If any exceptions set by this call, and are unmasked,
                   send a signal.  Old exceptions are not signaled.  */
                fex = (exc >> IEEE_STATUS_TO_EXCSUM_SHIFT) & swcr;
                if (fex) {
                        int si_code = FPE_FLTUNK;

                        if (fex & IEEE_TRAP_ENABLE_DNO) si_code = FPE_FLTUND;
                        if (fex & IEEE_TRAP_ENABLE_INE) si_code = FPE_FLTRES;
                        if (fex & IEEE_TRAP_ENABLE_UNF) si_code = FPE_FLTUND;
                        if (fex & IEEE_TRAP_ENABLE_OVF) si_code = FPE_FLTOVF;
                        if (fex & IEEE_TRAP_ENABLE_DZE) si_code = FPE_FLTDIV;
                        if (fex & IEEE_TRAP_ENABLE_INV) si_code = FPE_FLTINV;

                        send_sig_fault(SIGFPE, si_code,
                                       (void __user *)NULL,  /* FIXME */
                                       0, current);
                }
                return 0;
        }

        case SSI_IEEE_STATE_AT_SIGNAL:
        case SSI_IEEE_IGNORE_STATE_AT_SIGNAL:
                /*
                 * Not sure anybody will ever use this weird stuff.  These
                 * ops can be used (under OSF/1) to set the fpcr that should
                 * be used when a signal handler starts executing.
                 */
                break;

        case SSI_NVPAIRS: {
                unsigned __user *p = buffer;
                unsigned i;
                
                for (i = 0, p = buffer; i < nbytes; ++i, p += 2) {
                        unsigned v, w, status;

                        if (get_user(v, p) || get_user(w, p + 1))
                                return -EFAULT;
                        switch (v) {
                        case SSIN_UACPROC:
                                w &= UAC_BITMASK;
                                status = current_thread_info()->status;
                                status = (status & ~UAC_BITMASK) | w;
                                current_thread_info()->status = status;
                                break;
 
                        default:
                                return -EOPNOTSUPP;
                        }
                }
                return 0;
        }
 
        case SSI_LMF:
                return 0;

        default:
                break;
        }

        return -EOPNOTSUPP;
}

/* Translations due to the fact that OSF's time_t is an int.  Which
   affects all sorts of things, like timeval and itimerval.  */

extern struct timezone sys_tz;

struct timeval32
{
    int tv_sec, tv_usec;
};

struct itimerval32
{
    struct timeval32 it_interval;
    struct timeval32 it_value;
};

static inline long
get_tv32(struct timespec64 *o, struct timeval32 __user *i)
{
        struct timeval32 tv;
        if (copy_from_user(&tv, i, sizeof(struct timeval32)))
                return -EFAULT;
        o->tv_sec = tv.tv_sec;
        o->tv_nsec = tv.tv_usec * NSEC_PER_USEC;
        return 0;
}

static inline long
put_tv32(struct timeval32 __user *o, struct timespec64 *i)
{
        return copy_to_user(o, &(struct timeval32){
                                .tv_sec = i->tv_sec,
                                .tv_usec = i->tv_nsec / NSEC_PER_USEC},
                            sizeof(struct timeval32));
}

static inline long
put_tv_to_tv32(struct timeval32 __user *o, struct timeval *i)
{
        return copy_to_user(o, &(struct timeval32){
                                .tv_sec = i->tv_sec,
                                .tv_usec = i->tv_usec},
                            sizeof(struct timeval32));
}

static inline long
get_it32(struct itimerval *o, struct itimerval32 __user *i)
{
        struct itimerval32 itv;
        if (copy_from_user(&itv, i, sizeof(struct itimerval32)))
                return -EFAULT;
        o->it_interval.tv_sec = itv.it_interval.tv_sec;
        o->it_interval.tv_usec = itv.it_interval.tv_usec;
        o->it_value.tv_sec = itv.it_value.tv_sec;
        o->it_value.tv_usec = itv.it_value.tv_usec;
        return 0;
}

static inline long
put_it32(struct itimerval32 __user *o, struct itimerval *i)
{
        return copy_to_user(o, &(struct itimerval32){
                                .it_interval.tv_sec = o->it_interval.tv_sec,
                                .it_interval.tv_usec = o->it_interval.tv_usec,
                                .it_value.tv_sec = o->it_value.tv_sec,
                                .it_value.tv_usec = o->it_value.tv_usec},
                            sizeof(struct itimerval32));
}

static inline void
jiffies_to_timeval32(unsigned long jiffies, struct timeval32 *value)
{
        value->tv_usec = (jiffies % HZ) * (1000000L / HZ);
        value->tv_sec = jiffies / HZ;
}

SYSCALL_DEFINE2(osf_gettimeofday, struct timeval32 __user *, tv,
                struct timezone __user *, tz)
{
        if (tv) {
                struct timespec64 kts;

                ktime_get_real_ts64(&kts);
                if (put_tv32(tv, &kts))
                        return -EFAULT;
        }
        if (tz) {
                if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
                        return -EFAULT;
        }
        return 0;
}

SYSCALL_DEFINE2(osf_settimeofday, struct timeval32 __user *, tv,
                struct timezone __user *, tz)
{
        struct timespec64 kts;
        struct timezone ktz;

        if (tv) {
                if (get_tv32(&kts, tv))
                        return -EFAULT;
        }
        if (tz) {
                if (copy_from_user(&ktz, tz, sizeof(*tz)))
                        return -EFAULT;
        }

        return do_sys_settimeofday64(tv ? &kts : NULL, tz ? &ktz : NULL);
}

asmlinkage long sys_ni_posix_timers(void);

SYSCALL_DEFINE2(osf_getitimer, int, which, struct itimerval32 __user *, it)
{
        struct itimerval kit;
        int error;

        if (!IS_ENABLED(CONFIG_POSIX_TIMERS))
                return sys_ni_posix_timers();

        error = do_getitimer(which, &kit);
        if (!error && put_it32(it, &kit))
                error = -EFAULT;

        return error;
}

SYSCALL_DEFINE3(osf_setitimer, int, which, struct itimerval32 __user *, in,
                struct itimerval32 __user *, out)
{
        struct itimerval kin, kout;
        int error;

        if (!IS_ENABLED(CONFIG_POSIX_TIMERS))
                return sys_ni_posix_timers();

        if (in) {
                if (get_it32(&kin, in))
                        return -EFAULT;
        } else
                memset(&kin, 0, sizeof(kin));

        error = do_setitimer(which, &kin, out ? &kout : NULL);
        if (error || !out)
                return error;

        if (put_it32(out, &kout))
                return -EFAULT;

        return 0;

}

SYSCALL_DEFINE2(osf_utimes, const char __user *, filename,
                struct timeval32 __user *, tvs)
{
        struct timespec64 tv[2];

        if (tvs) {
                if (get_tv32(&tv[0], &tvs[0]) ||
                    get_tv32(&tv[1], &tvs[1]))
                        return -EFAULT;

                if (tv[0].tv_nsec < 0 || tv[0].tv_nsec >= 1000000000 ||
                    tv[1].tv_nsec < 0 || tv[1].tv_nsec >= 1000000000)
                        return -EINVAL;
        }

        return do_utimes(AT_FDCWD, filename, tvs ? tv : NULL, 0);
}

SYSCALL_DEFINE5(osf_select, int, n, fd_set __user *, inp, fd_set __user *, outp,
                fd_set __user *, exp, struct timeval32 __user *, tvp)
{
        struct timespec64 end_time, *to = NULL;
        if (tvp) {
                struct timespec64 tv;
                to = &end_time;

                if (get_tv32(&tv, tvp))
                        return -EFAULT;

                if (tv.tv_sec < 0 || tv.tv_nsec < 0)
                        return -EINVAL;

                if (poll_select_set_timeout(to, tv.tv_sec, tv.tv_nsec))
                        return -EINVAL;         

        }

        /* OSF does not copy back the remaining time.  */
        return core_sys_select(n, inp, outp, exp, to);
}

struct rusage32 {
        struct timeval32 ru_utime;      /* user time used */
        struct timeval32 ru_stime;      /* system time used */
        long    ru_maxrss;              /* maximum resident set size */
        long    ru_ixrss;               /* integral shared memory size */
        long    ru_idrss;               /* integral unshared data size */
        long    ru_isrss;               /* integral unshared stack size */
        long    ru_minflt;              /* page reclaims */
        long    ru_majflt;              /* page faults */
        long    ru_nswap;               /* swaps */
        long    ru_inblock;             /* block input operations */
        long    ru_oublock;             /* block output operations */
        long    ru_msgsnd;              /* messages sent */
        long    ru_msgrcv;              /* messages received */
        long    ru_nsignals;            /* signals received */
        long    ru_nvcsw;               /* voluntary context switches */
        long    ru_nivcsw;              /* involuntary " */
};

SYSCALL_DEFINE2(osf_getrusage, int, who, struct rusage32 __user *, ru)
{
        struct rusage32 r;
        u64 utime, stime;
        unsigned long utime_jiffies, stime_jiffies;

        if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
                return -EINVAL;

        memset(&r, 0, sizeof(r));
        switch (who) {
        case RUSAGE_SELF:
                task_cputime(current, &utime, &stime);
                utime_jiffies = nsecs_to_jiffies(utime);
                stime_jiffies = nsecs_to_jiffies(stime);
                jiffies_to_timeval32(utime_jiffies, &r.ru_utime);
                jiffies_to_timeval32(stime_jiffies, &r.ru_stime);
                r.ru_minflt = current->min_flt;
                r.ru_majflt = current->maj_flt;
                break;
        case RUSAGE_CHILDREN:
                utime_jiffies = nsecs_to_jiffies(current->signal->cutime);
                stime_jiffies = nsecs_to_jiffies(current->signal->cstime);
                jiffies_to_timeval32(utime_jiffies, &r.ru_utime);
                jiffies_to_timeval32(stime_jiffies, &r.ru_stime);
                r.ru_minflt = current->signal->cmin_flt;
                r.ru_majflt = current->signal->cmaj_flt;
                break;
        }

        return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
}

SYSCALL_DEFINE4(osf_wait4, pid_t, pid, int __user *, ustatus, int, options,
                struct rusage32 __user *, ur)
{
        struct rusage r;
        long err = kernel_wait4(pid, ustatus, options, &r);
        if (err <= 0)
                return err;
        if (!ur)
                return err;
        if (put_tv_to_tv32(&ur->ru_utime, &r.ru_utime))
                return -EFAULT;
        if (put_tv_to_tv32(&ur->ru_stime, &r.ru_stime))
                return -EFAULT;
        if (copy_to_user(&ur->ru_maxrss, &r.ru_maxrss,
              sizeof(struct rusage32) - offsetof(struct rusage32, ru_maxrss)))
                return -EFAULT;
        return err;
}

/*
 * I don't know what the parameters are: the first one
 * seems to be a timeval pointer, and I suspect the second
 * one is the time remaining.. Ho humm.. No documentation.
 */
SYSCALL_DEFINE2(osf_usleep_thread, struct timeval32 __user *, sleep,
                struct timeval32 __user *, remain)
{
        struct timespec64 tmp;
        unsigned long ticks;

        if (get_tv32(&tmp, sleep))
                goto fault;

        ticks = timespec64_to_jiffies(&tmp);

        ticks = schedule_timeout_interruptible(ticks);

        if (remain) {
                jiffies_to_timespec64(ticks, &tmp);
                if (put_tv32(remain, &tmp))
                        goto fault;
        }
        
        return 0;
 fault:
        return -EFAULT;
}


struct timex32 {
        unsigned int modes;     /* mode selector */
        long offset;            /* time offset (usec) */
        long freq;              /* frequency offset (scaled ppm) */
        long maxerror;          /* maximum error (usec) */
        long esterror;          /* estimated error (usec) */
        int status;             /* clock command/status */
        long constant;          /* pll time constant */
        long precision;         /* clock precision (usec) (read only) */
        long tolerance;         /* clock frequency tolerance (ppm)
                                 * (read only)
                                 */
        struct timeval32 time;  /* (read only) */
        long tick;              /* (modified) usecs between clock ticks */

        long ppsfreq;           /* pps frequency (scaled ppm) (ro) */
        long jitter;            /* pps jitter (us) (ro) */
        int shift;              /* interval duration (s) (shift) (ro) */
        long stabil;            /* pps stability (scaled ppm) (ro) */
        long jitcnt;            /* jitter limit exceeded (ro) */
        long calcnt;            /* calibration intervals (ro) */
        long errcnt;            /* calibration errors (ro) */
        long stbcnt;            /* stability limit exceeded (ro) */

        int  :32; int  :32; int  :32; int  :32;
        int  :32; int  :32; int  :32; int  :32;
        int  :32; int  :32; int  :32; int  :32;
};

SYSCALL_DEFINE1(old_adjtimex, struct timex32 __user *, txc_p)
{
        struct timex txc;
        int ret;

        /* copy relevant bits of struct timex. */
        if (copy_from_user(&txc, txc_p, offsetof(struct timex32, time)) ||
            copy_from_user(&txc.tick, &txc_p->tick, sizeof(struct timex32) - 
                           offsetof(struct timex32, tick)))
          return -EFAULT;

        ret = do_adjtimex(&txc);        
        if (ret < 0)
          return ret;
        
        /* copy back to timex32 */
        if (copy_to_user(txc_p, &txc, offsetof(struct timex32, time)) ||
            (copy_to_user(&txc_p->tick, &txc.tick, sizeof(struct timex32) - 
                          offsetof(struct timex32, tick))) ||
            (put_tv_to_tv32(&txc_p->time, &txc.time)))
          return -EFAULT;

        return ret;
}

/* Get an address range which is currently unmapped.  Similar to the
   generic version except that we know how to honor ADDR_LIMIT_32BIT.  */

static unsigned long
arch_get_unmapped_area_1(unsigned long addr, unsigned long len,
                         unsigned long limit)
{
        struct vm_unmapped_area_info info;

        info.flags = 0;
        info.length = len;
        info.low_limit = addr;
        info.high_limit = limit;
        info.align_mask = 0;
        info.align_offset = 0;
        return vm_unmapped_area(&info);
}

unsigned long
arch_get_unmapped_area(struct file *filp, unsigned long addr,
                       unsigned long len, unsigned long pgoff,
                       unsigned long flags)
{
        unsigned long limit;

        /* "32 bit" actually means 31 bit, since pointers sign extend.  */
        if (current->personality & ADDR_LIMIT_32BIT)
                limit = 0x80000000;
        else
                limit = TASK_SIZE;

        if (len > limit)
                return -ENOMEM;

        if (flags & MAP_FIXED)
                return addr;

        /* First, see if the given suggestion fits.

           The OSF/1 loader (/sbin/loader) relies on us returning an
           address larger than the requested if one exists, which is
           a terribly broken way to program.

           That said, I can see the use in being able to suggest not
           merely specific addresses, but regions of memory -- perhaps
           this feature should be incorporated into all ports?  */

        if (addr) {
                addr = arch_get_unmapped_area_1 (PAGE_ALIGN(addr), len, limit);
                if (addr != (unsigned long) -ENOMEM)
                        return addr;
        }

        /* Next, try allocating at TASK_UNMAPPED_BASE.  */
        addr = arch_get_unmapped_area_1 (PAGE_ALIGN(TASK_UNMAPPED_BASE),
                                         len, limit);
        if (addr != (unsigned long) -ENOMEM)
                return addr;

        /* Finally, try allocating in low memory.  */
        addr = arch_get_unmapped_area_1 (PAGE_SIZE, len, limit);

        return addr;
}

#ifdef CONFIG_OSF4_COMPAT

/* Clear top 32 bits of iov_len in the user's buffer for
   compatibility with old versions of OSF/1 where iov_len
   was defined as int. */
static int
osf_fix_iov_len(const struct iovec __user *iov, unsigned long count)
{
        unsigned long i;

        for (i = 0 ; i < count ; i++) {
                int __user *iov_len_high = (int __user *)&iov[i].iov_len + 1;

                if (put_user(0, iov_len_high))
                        return -EFAULT;
        }
        return 0;
}

SYSCALL_DEFINE3(osf_readv, unsigned long, fd,
                const struct iovec __user *, vector, unsigned long, count)
{
        if (unlikely(personality(current->personality) == PER_OSF4))
                if (osf_fix_iov_len(vector, count))
                        return -EFAULT;
        return sys_readv(fd, vector, count);
}

SYSCALL_DEFINE3(osf_writev, unsigned long, fd,
                const struct iovec __user *, vector, unsigned long, count)
{
        if (unlikely(personality(current->personality) == PER_OSF4))
                if (osf_fix_iov_len(vector, count))
                        return -EFAULT;
        return sys_writev(fd, vector, count);
}

#endif

SYSCALL_DEFINE2(osf_getpriority, int, which, int, who)
{
        int prio = sys_getpriority(which, who);
        if (prio >= 0) {
                /* Return value is the unbiased priority, i.e. 20 - prio.
                   This does result in negative return values, so signal
                   no error */
                force_successful_syscall_return();
                prio = 20 - prio;
        }
        return prio;
}

SYSCALL_DEFINE0(getxuid)
{
        current_pt_regs()->r20 = sys_geteuid();
        return sys_getuid();
}

SYSCALL_DEFINE0(getxgid)
{
        current_pt_regs()->r20 = sys_getegid();
        return sys_getgid();
}

SYSCALL_DEFINE0(getxpid)
{
        current_pt_regs()->r20 = sys_getppid();
        return sys_getpid();
}

SYSCALL_DEFINE0(alpha_pipe)
{
        int fd[2];
        int res = do_pipe_flags(fd, 0);
        if (!res) {
                /* The return values are in $0 and $20.  */
                current_pt_regs()->r20 = fd[1];
                res = fd[0];
        }
        return res;
}

SYSCALL_DEFINE1(sethae, unsigned long, val)
{
        current_pt_regs()->hae = val;
        return 0;
}