linux_dsm_epyc7002/arch/sparc/kernel/systbls_64.S
David S. Miller 517ffce4e1 sparc64: Make montmul/montsqr/mpmul usable in 32-bit threads.
The Montgomery Multiply, Montgomery Square, and Multiple-Precision
Multiply instructions work by loading a combination of the floating
point and multiple register windows worth of integer registers
with the inputs.

These values are 64-bit.  But for 32-bit userland processes we only
save the low 32-bits of each integer register during a register spill.
This is because the register window save area is in the user stack and
has a fixed layout.

Therefore, the only way to use these instruction in 32-bit mode is to
perform the following sequence:

1) Load the top-32bits of a choosen integer register with a sentinel,
   say "-1".  This will be in the outer-most register window.

   The idea is that we're trying to see if the outer-most register
   window gets spilled, and thus the 64-bit values were truncated.

2) Load all the inputs for the montmul/montsqr/mpmul instruction,
   down to the inner-most register window.

3) Execute the opcode.

4) Traverse back up to the outer-most register window.

5) Check the sentinel, if it's still "-1" store the results.
   Otherwise retry the entire sequence.

This retry is extremely troublesome.  If you're just unlucky and an
interrupt or other trap happens, it'll push that outer-most window to
the stack and clear the sentinel when we restore it.

We could retry forever and never make forward progress if interrupts
arrive at a fast enough rate (consider perf events as one example).
So we have do limited retries and fallback to software which is
extremely non-deterministic.

Luckily it's very straightforward to provide a mechanism to let
32-bit applications use a 64-bit stack.  Stacks in 64-bit mode are
biased by 2047 bytes, which means that the lowest bit is set in the
actual %sp register value.

So if we see bit zero set in a 32-bit application's stack we treat
it like a 64-bit stack.

Runtime detection of such a facility is tricky, and cumbersome at
best.  For example, just trying to use a biased stack and seeing if it
works is hard to recover from (the signal handler will need to use an
alt stack, plus something along the lines of longjmp).  Therefore, we
add a system call to report a bitmask of arch specific features like
this in a cheap and less hairy way.

With help from Andy Polyakov.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-26 15:18:37 -07:00

168 lines
13 KiB
ArmAsm

/* systbls.S: System call entry point tables for OS compatibility.
* The native Linux system call table lives here also.
*
* Copyright (C) 1995, 1996, 2007 David S. Miller (davem@davemloft.net)
* Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*
* Based upon preliminary work which is:
*
* Copyright (C) 1995 Adrian M. Rodriguez (adrian@remus.rutgers.edu)
*/
.text
.align 4
#ifdef CONFIG_COMPAT
/* First, the 32-bit Linux native syscall table. */
.globl sys_call_table32
sys_call_table32:
/*0*/ .word sys_restart_syscall, sys32_exit, sys_fork, sys_read, sys_write
/*5*/ .word sys32_open, sys_close, sys32_wait4, sys32_creat, sys_link
/*10*/ .word sys_unlink, sunos_execv, sys_chdir, sys_chown16, sys32_mknod
/*15*/ .word sys_chmod, sys_lchown16, sys_brk, sys_nis_syscall, sys32_lseek
/*20*/ .word sys_getpid, sys_capget, sys_capset, sys_setuid16, sys_getuid16
/*25*/ .word sys32_vmsplice, compat_sys_ptrace, sys_alarm, sys32_sigaltstack, sys_pause
/*30*/ .word compat_sys_utime, sys_lchown, sys_fchown, sys32_access, sys32_nice
.word sys_chown, sys_sync, sys32_kill, compat_sys_newstat, sys32_sendfile
/*40*/ .word compat_sys_newlstat, sys_dup, sys_sparc_pipe, compat_sys_times, sys_getuid
.word sys32_umount, sys_setgid16, sys_getgid16, sys32_signal, sys_geteuid16
/*50*/ .word sys_getegid16, sys_acct, sys_nis_syscall, sys_getgid, compat_sys_ioctl
.word sys32_reboot, sys32_mmap2, sys_symlink, sys32_readlink, sys32_execve
/*60*/ .word sys32_umask, sys_chroot, compat_sys_newfstat, compat_sys_fstat64, sys_getpagesize
.word sys32_msync, sys_vfork, sys32_pread64, sys32_pwrite64, sys_geteuid
/*70*/ .word sys_getegid, sys_mmap, sys_setreuid, sys_munmap, sys_mprotect
.word sys_madvise, sys_vhangup, sys32_truncate64, sys_mincore, sys_getgroups16
/*80*/ .word sys_setgroups16, sys_getpgrp, sys32_setgroups, sys32_setitimer, sys32_ftruncate64
.word sys32_swapon, sys32_getitimer, sys_setuid, sys32_sethostname, sys_setgid
/*90*/ .word sys_dup2, sys_setfsuid, compat_sys_fcntl, sys32_select, sys_setfsgid
.word sys_fsync, sys32_setpriority, sys_nis_syscall, sys_nis_syscall, sys_nis_syscall
/*100*/ .word sys32_getpriority, sys32_rt_sigreturn, sys32_rt_sigaction, sys32_rt_sigprocmask, sys32_rt_sigpending
.word compat_sys_rt_sigtimedwait, sys32_rt_sigqueueinfo, compat_sys_rt_sigsuspend, sys_setresuid, sys_getresuid
/*110*/ .word sys_setresgid, sys_getresgid, sys_setregid, sys_nis_syscall, sys_nis_syscall
.word sys32_getgroups, compat_sys_gettimeofday, sys32_getrusage, sys_nis_syscall, sys_getcwd
/*120*/ .word compat_sys_readv, compat_sys_writev, compat_sys_settimeofday, sys_fchown16, sys_fchmod
.word sys_nis_syscall, sys_setreuid16, sys_setregid16, sys_rename, sys32_truncate
/*130*/ .word sys32_ftruncate, sys_flock, compat_sys_lstat64, sys_nis_syscall, sys_nis_syscall
.word sys_nis_syscall, sys32_mkdir, sys_rmdir, compat_sys_utimes, compat_sys_stat64
/*140*/ .word sys32_sendfile64, sys_nis_syscall, sys32_futex, sys_gettid, compat_sys_getrlimit
.word compat_sys_setrlimit, sys_pivot_root, sys32_prctl, sys_pciconfig_read, sys_pciconfig_write
/*150*/ .word sys_nis_syscall, sys_inotify_init, sys_inotify_add_watch, sys_poll, sys_getdents64
.word compat_sys_fcntl64, sys_inotify_rm_watch, compat_sys_statfs, compat_sys_fstatfs, sys_oldumount
/*160*/ .word compat_sys_sched_setaffinity, compat_sys_sched_getaffinity, sys32_getdomainname, sys32_setdomainname, sys_nis_syscall
.word sys_quotactl, sys_set_tid_address, compat_sys_mount, compat_sys_ustat, sys32_setxattr
/*170*/ .word sys32_lsetxattr, sys32_fsetxattr, sys_getxattr, sys_lgetxattr, compat_sys_getdents
.word sys_setsid, sys_fchdir, sys32_fgetxattr, sys_listxattr, sys_llistxattr
/*180*/ .word sys32_flistxattr, sys_removexattr, sys_lremovexattr, compat_sys_sigpending, sys_ni_syscall
.word sys32_setpgid, sys32_fremovexattr, sys32_tkill, sys32_exit_group, sys_newuname
/*190*/ .word sys32_init_module, sys_sparc64_personality, sys_remap_file_pages, sys32_epoll_create, sys32_epoll_ctl
.word sys32_epoll_wait, sys32_ioprio_set, sys_getppid, sys32_sigaction, sys_sgetmask
/*200*/ .word sys32_ssetmask, sys_sigsuspend, compat_sys_newlstat, sys_uselib, compat_sys_old_readdir
.word sys32_readahead, sys32_socketcall, sys32_syslog, sys32_lookup_dcookie, sys32_fadvise64
/*210*/ .word sys32_fadvise64_64, sys32_tgkill, sys32_waitpid, sys_swapoff, compat_sys_sysinfo
.word compat_sys_ipc, sys32_sigreturn, sys_clone, sys32_ioprio_get, compat_sys_adjtimex
/*220*/ .word sys32_sigprocmask, sys_ni_syscall, sys32_delete_module, sys_ni_syscall, sys32_getpgid
.word sys32_bdflush, sys32_sysfs, sys_nis_syscall, sys_setfsuid16, sys_setfsgid16
/*230*/ .word sys32_select, compat_sys_time, sys32_splice, compat_sys_stime, compat_sys_statfs64
.word compat_sys_fstatfs64, sys_llseek, sys_mlock, sys_munlock, sys32_mlockall
/*240*/ .word sys_munlockall, sys32_sched_setparam, sys32_sched_getparam, sys32_sched_setscheduler, sys32_sched_getscheduler
.word sys_sched_yield, sys32_sched_get_priority_max, sys32_sched_get_priority_min, sys32_sched_rr_get_interval, compat_sys_nanosleep
/*250*/ .word sys_mremap, compat_sys_sysctl, sys32_getsid, sys_fdatasync, sys_nis_syscall
.word sys32_sync_file_range, compat_sys_clock_settime, compat_sys_clock_gettime, compat_sys_clock_getres, sys32_clock_nanosleep
/*260*/ .word compat_sys_sched_getaffinity, compat_sys_sched_setaffinity, sys32_timer_settime, compat_sys_timer_gettime, sys_timer_getoverrun
.word sys_timer_delete, compat_sys_timer_create, sys_ni_syscall, compat_sys_io_setup, sys_io_destroy
/*270*/ .word sys32_io_submit, sys_io_cancel, compat_sys_io_getevents, sys32_mq_open, sys_mq_unlink
.word compat_sys_mq_timedsend, compat_sys_mq_timedreceive, compat_sys_mq_notify, compat_sys_mq_getsetattr, compat_sys_waitid
/*280*/ .word sys32_tee, sys_add_key, sys_request_key, compat_sys_keyctl, compat_sys_openat
.word sys_mkdirat, sys_mknodat, sys_fchownat, compat_sys_futimesat, compat_sys_fstatat64
/*290*/ .word sys_unlinkat, sys_renameat, sys_linkat, sys_symlinkat, sys_readlinkat
.word sys_fchmodat, sys_faccessat, compat_sys_pselect6, compat_sys_ppoll, sys_unshare
/*300*/ .word compat_sys_set_robust_list, compat_sys_get_robust_list, compat_sys_migrate_pages, compat_sys_mbind, compat_sys_get_mempolicy
.word compat_sys_set_mempolicy, compat_sys_kexec_load, compat_sys_move_pages, sys_getcpu, compat_sys_epoll_pwait
/*310*/ .word compat_sys_utimensat, compat_sys_signalfd, sys_timerfd_create, sys_eventfd, compat_sys_fallocate
.word compat_sys_timerfd_settime, compat_sys_timerfd_gettime, compat_sys_signalfd4, sys_eventfd2, sys_epoll_create1
/*320*/ .word sys_dup3, sys_pipe2, sys_inotify_init1, sys_accept4, compat_sys_preadv
.word compat_sys_pwritev, compat_sys_rt_tgsigqueueinfo, sys_perf_event_open, compat_sys_recvmmsg, sys_fanotify_init
/*330*/ .word sys32_fanotify_mark, sys_prlimit64, sys_name_to_handle_at, compat_sys_open_by_handle_at, compat_sys_clock_adjtime
.word sys_syncfs, compat_sys_sendmmsg, sys_setns, compat_sys_process_vm_readv, compat_sys_process_vm_writev
/*340*/ .word sys_kern_features
#endif /* CONFIG_COMPAT */
/* Now the 64-bit native Linux syscall table. */
.align 4
.globl sys_call_table64, sys_call_table
sys_call_table64:
sys_call_table:
/*0*/ .word sys_restart_syscall, sparc_exit, sys_fork, sys_read, sys_write
/*5*/ .word sys_open, sys_close, sys_wait4, sys_creat, sys_link
/*10*/ .word sys_unlink, sys_nis_syscall, sys_chdir, sys_chown, sys_mknod
/*15*/ .word sys_chmod, sys_lchown, sys_brk, sys_nis_syscall, sys_lseek
/*20*/ .word sys_getpid, sys_capget, sys_capset, sys_setuid, sys_getuid
/*25*/ .word sys_vmsplice, sys_ptrace, sys_alarm, sys_sigaltstack, sys_nis_syscall
/*30*/ .word sys_utime, sys_nis_syscall, sys_nis_syscall, sys_access, sys_nice
.word sys_nis_syscall, sys_sync, sys_kill, sys_newstat, sys_sendfile64
/*40*/ .word sys_newlstat, sys_dup, sys_sparc_pipe, sys_times, sys_nis_syscall
.word sys_umount, sys_setgid, sys_getgid, sys_signal, sys_geteuid
/*50*/ .word sys_getegid, sys_acct, sys_memory_ordering, sys_nis_syscall, sys_ioctl
.word sys_reboot, sys_nis_syscall, sys_symlink, sys_readlink, sys_execve
/*60*/ .word sys_umask, sys_chroot, sys_newfstat, sys_fstat64, sys_getpagesize
.word sys_msync, sys_vfork, sys_pread64, sys_pwrite64, sys_nis_syscall
/*70*/ .word sys_nis_syscall, sys_mmap, sys_nis_syscall, sys_64_munmap, sys_mprotect
.word sys_madvise, sys_vhangup, sys_nis_syscall, sys_mincore, sys_getgroups
/*80*/ .word sys_setgroups, sys_getpgrp, sys_nis_syscall, sys_setitimer, sys_nis_syscall
.word sys_swapon, sys_getitimer, sys_nis_syscall, sys_sethostname, sys_nis_syscall
/*90*/ .word sys_dup2, sys_nis_syscall, sys_fcntl, sys_select, sys_nis_syscall
.word sys_fsync, sys_setpriority, sys_socket, sys_connect, sys_accept
/*100*/ .word sys_getpriority, sys_rt_sigreturn, sys_rt_sigaction, sys_rt_sigprocmask, sys_rt_sigpending
.word sys_rt_sigtimedwait, sys_rt_sigqueueinfo, sys_rt_sigsuspend, sys_setresuid, sys_getresuid
/*110*/ .word sys_setresgid, sys_getresgid, sys_nis_syscall, sys_recvmsg, sys_sendmsg
.word sys_nis_syscall, sys_gettimeofday, sys_getrusage, sys_getsockopt, sys_getcwd
/*120*/ .word sys_readv, sys_writev, sys_settimeofday, sys_fchown, sys_fchmod
.word sys_recvfrom, sys_setreuid, sys_setregid, sys_rename, sys_truncate
/*130*/ .word sys_ftruncate, sys_flock, sys_lstat64, sys_sendto, sys_shutdown
.word sys_socketpair, sys_mkdir, sys_rmdir, sys_utimes, sys_stat64
/*140*/ .word sys_sendfile64, sys_getpeername, sys_futex, sys_gettid, sys_getrlimit
.word sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
/*150*/ .word sys_getsockname, sys_inotify_init, sys_inotify_add_watch, sys_poll, sys_getdents64
.word sys_nis_syscall, sys_inotify_rm_watch, sys_statfs, sys_fstatfs, sys_oldumount
/*160*/ .word sys_sched_setaffinity, sys_sched_getaffinity, sys_getdomainname, sys_setdomainname, sys_utrap_install
.word sys_quotactl, sys_set_tid_address, sys_mount, sys_ustat, sys_setxattr
/*170*/ .word sys_lsetxattr, sys_fsetxattr, sys_getxattr, sys_lgetxattr, sys_getdents
.word sys_setsid, sys_fchdir, sys_fgetxattr, sys_listxattr, sys_llistxattr
/*180*/ .word sys_flistxattr, sys_removexattr, sys_lremovexattr, sys_nis_syscall, sys_ni_syscall
.word sys_setpgid, sys_fremovexattr, sys_tkill, sys_exit_group, sys_newuname
/*190*/ .word sys_init_module, sys_sparc64_personality, sys_remap_file_pages, sys_epoll_create, sys_epoll_ctl
.word sys_epoll_wait, sys_ioprio_set, sys_getppid, sys_nis_syscall, sys_sgetmask
/*200*/ .word sys_ssetmask, sys_nis_syscall, sys_newlstat, sys_uselib, sys_nis_syscall
.word sys_readahead, sys_socketcall, sys_syslog, sys_lookup_dcookie, sys_fadvise64
/*210*/ .word sys_fadvise64_64, sys_tgkill, sys_waitpid, sys_swapoff, sys_sysinfo
.word sys_sparc_ipc, sys_nis_syscall, sys_clone, sys_ioprio_get, sys_adjtimex
/*220*/ .word sys_nis_syscall, sys_ni_syscall, sys_delete_module, sys_ni_syscall, sys_getpgid
.word sys_bdflush, sys_sysfs, sys_nis_syscall, sys_setfsuid, sys_setfsgid
/*230*/ .word sys_select, sys_nis_syscall, sys_splice, sys_stime, sys_statfs64
.word sys_fstatfs64, sys_llseek, sys_mlock, sys_munlock, sys_mlockall
/*240*/ .word sys_munlockall, sys_sched_setparam, sys_sched_getparam, sys_sched_setscheduler, sys_sched_getscheduler
.word sys_sched_yield, sys_sched_get_priority_max, sys_sched_get_priority_min, sys_sched_rr_get_interval, sys_nanosleep
/*250*/ .word sys_64_mremap, sys_sysctl, sys_getsid, sys_fdatasync, sys_nis_syscall
.word sys_sync_file_range, sys_clock_settime, sys_clock_gettime, sys_clock_getres, sys_clock_nanosleep
/*260*/ .word sys_sched_getaffinity, sys_sched_setaffinity, sys_timer_settime, sys_timer_gettime, sys_timer_getoverrun
.word sys_timer_delete, sys_timer_create, sys_ni_syscall, sys_io_setup, sys_io_destroy
/*270*/ .word sys_io_submit, sys_io_cancel, sys_io_getevents, sys_mq_open, sys_mq_unlink
.word sys_mq_timedsend, sys_mq_timedreceive, sys_mq_notify, sys_mq_getsetattr, sys_waitid
/*280*/ .word sys_tee, sys_add_key, sys_request_key, sys_keyctl, sys_openat
.word sys_mkdirat, sys_mknodat, sys_fchownat, sys_futimesat, sys_fstatat64
/*290*/ .word sys_unlinkat, sys_renameat, sys_linkat, sys_symlinkat, sys_readlinkat
.word sys_fchmodat, sys_faccessat, sys_pselect6, sys_ppoll, sys_unshare
/*300*/ .word sys_set_robust_list, sys_get_robust_list, sys_migrate_pages, sys_mbind, sys_get_mempolicy
.word sys_set_mempolicy, sys_kexec_load, sys_move_pages, sys_getcpu, sys_epoll_pwait
/*310*/ .word sys_utimensat, sys_signalfd, sys_timerfd_create, sys_eventfd, sys_fallocate
.word sys_timerfd_settime, sys_timerfd_gettime, sys_signalfd4, sys_eventfd2, sys_epoll_create1
/*320*/ .word sys_dup3, sys_pipe2, sys_inotify_init1, sys_accept4, sys_preadv
.word sys_pwritev, sys_rt_tgsigqueueinfo, sys_perf_event_open, sys_recvmmsg, sys_fanotify_init
/*330*/ .word sys_fanotify_mark, sys_prlimit64, sys_name_to_handle_at, sys_open_by_handle_at, sys_clock_adjtime
.word sys_syncfs, sys_sendmmsg, sys_setns, sys_process_vm_readv, sys_process_vm_writev
/*340*/ .word sys_kern_features