diff options
author | Jeff Dike <jdike@addtoit.com> | 2007-10-16 01:26:47 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-16 09:43:05 -0700 |
commit | 42daba316557e597a90a730f61c762602b7f0e0c (patch) | |
tree | 9b7e9da84cef7d2547c577f1cf94b408cf308619 /arch/um/os-Linux/sys-i386/registers.c | |
parent | 5c8aaceab88ac787c0a4038b29143c954c2a45e0 (diff) |
uml: stop saving process FP state
Throw out a lot of code dealing with saving and restoring floating-point
state. In skas mode, where processes run in a restoring floating-point state
on kernel entry and exit is pointless.
This eliminates most of arch/um/os-Linux/sys-{i386,x86_64}/registers.c. Most
of what remained is now arch-indpendent, and can be moved up to
arch/um/os-Linux/registers.c. Both arches need the jmp_buf accessor
get_thread_reg, and i386 needs {save,restore}_fp_regs because it cheats during
sigreturn by getting the fp state using ptrace rather than copying it out of
the process sigcontext.
After this, it turns out that arch/um/include/skas/mode-skas.h is almost
completely unneeded. The declarations in it are variables which either don't
exist or which don't have global scope. The one exception is
kill_off_processes_skas. If that's removed, this header can be deleted.
This uncovered a bug in user.h, which wasn't correctly making sure that a
size_t definition was available to both userspace and kernelspace files.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/um/os-Linux/sys-i386/registers.c')
-rw-r--r-- | arch/um/os-Linux/sys-i386/registers.c | 108 |
1 files changed, 1 insertions, 107 deletions
diff --git a/arch/um/os-Linux/sys-i386/registers.c b/arch/um/os-Linux/sys-i386/registers.c index 84b44f9cd42..f171204caa4 100644 --- a/arch/um/os-Linux/sys-i386/registers.c +++ b/arch/um/os-Linux/sys-i386/registers.c @@ -4,30 +4,10 @@ */ #include <errno.h> -#include <string.h> -#include "sysdep/ptrace_user.h" -#include "sysdep/ptrace.h" -#include "uml-config.h" -#include "skas_ptregs.h" -#include "registers.h" +#include <sysdep/ptrace_user.h> #include "longjmp.h" #include "user.h" -/* These are set once at boot time and not changed thereafter */ - -static unsigned long exec_regs[MAX_REG_NR]; -static unsigned long exec_fp_regs[HOST_FP_SIZE]; -static unsigned long exec_fpx_regs[HOST_XFP_SIZE]; -static int have_fpx_regs = 1; - -void init_thread_registers(union uml_pt_regs *to) -{ - memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs)); - memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp)); - if(have_fpx_regs) - memcpy(to->skas.xfp, exec_fpx_regs, sizeof(to->skas.xfp)); -} - /* XXX These need to use [GS]ETFPXREGS and copy_sc_{to,from}_user_skas needs * to pass in a sufficiently large buffer */ @@ -45,92 +25,6 @@ int restore_fp_registers(int pid, unsigned long *fp_regs) return 0; } -static int move_registers(int pid, int int_op, union uml_pt_regs *regs, - int fp_op, unsigned long *fp_regs) -{ - if(ptrace(int_op, pid, 0, regs->skas.regs) < 0) - return -errno; - - if(ptrace(fp_op, pid, 0, fp_regs) < 0) - return -errno; - - return 0; -} - -void save_registers(int pid, union uml_pt_regs *regs) -{ - unsigned long *fp_regs; - int err, fp_op; - - if(have_fpx_regs){ - fp_op = PTRACE_GETFPXREGS; - fp_regs = regs->skas.xfp; - } - else { - fp_op = PTRACE_GETFPREGS; - fp_regs = regs->skas.fp; - } - - err = move_registers(pid, PTRACE_GETREGS, regs, fp_op, fp_regs); - if(err) - panic("save_registers - saving registers failed, errno = %d\n", - -err); -} - -void restore_registers(int pid, union uml_pt_regs *regs) -{ - unsigned long *fp_regs; - int err, fp_op; - - if(have_fpx_regs){ - fp_op = PTRACE_SETFPXREGS; - fp_regs = regs->skas.xfp; - } - else { - fp_op = PTRACE_SETFPREGS; - fp_regs = regs->skas.fp; - } - - err = move_registers(pid, PTRACE_SETREGS, regs, fp_op, fp_regs); - if(err) - panic("restore_registers - saving registers failed, " - "errno = %d\n", -err); -} - -void init_registers(int pid) -{ - int err; - - memset(exec_regs, 0, sizeof(exec_regs)); - err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs); - if(err) - panic("check_ptrace : PTRACE_GETREGS failed, errno = %d", - errno); - - errno = 0; - err = ptrace(PTRACE_GETFPXREGS, pid, 0, exec_fpx_regs); - if(!err) - return; - if(errno != EIO) - panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d", - errno); - - have_fpx_regs = 0; - - err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs); - if(err) - panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d", - errno); -} - -void get_safe_registers(unsigned long *regs, unsigned long *fp_regs) -{ - memcpy(regs, exec_regs, sizeof(exec_regs)); - if(fp_regs != NULL) - memcpy(fp_regs, exec_fp_regs, - HOST_FP_SIZE * sizeof(unsigned long)); -} - unsigned long get_thread_reg(int reg, jmp_buf *buf) { switch(reg){ |