diff options
| author | Eli Cooper <elicooper@gmx.com> | 2016-03-20 00:58:41 +0800 |
|---|---|---|
| committer | Richard Weinberger <richard@nod.at> | 2016-05-21 23:38:06 +0200 |
| commit | a78ff1112263fdd871d3506dbcff44f6f12e8423 (patch) | |
| tree | e57ced8c83977e3686b8a69343cc5541565b8b94 /arch/x86/um/os-Linux | |
| parent | b6024b21fec8367ef961a771cc9dde31f1831965 (diff) | |
um: add extended processor state save/restore support
This patch extends save_fp_registers() and restore_fp_registers() to use
PTRACE_GETREGSET and PTRACE_SETREGSET with the XSTATE note type, adding
support for new processor state extensions between context switches.
When the new ptrace requests are unavailable, it falls back to the old
PTRACE_GETFPREGS and PTRACE_SETFPREGS methods, which have been renamed to
save_i387_registers() and restore_i387_registers().
Now these functions expect *fp_regs to have the space of an _xstate struct.
Thus, this also makes ptrace in UML responde to PTRACE_GETFPREGS/_SETFPREG
requests with a user_i387_struct (thus independent from HOST_FP_SIZE), and
by calling save_i387_registers() and restore_i387_registers() instead of
the extended save_fp_registers() and restore_fp_registers() functions.
Signed-off-by: Eli Cooper <elicooper@gmx.com>
Diffstat (limited to 'arch/x86/um/os-Linux')
| -rw-r--r-- | arch/x86/um/os-Linux/registers.c | 49 |
1 files changed, 47 insertions, 2 deletions
diff --git a/arch/x86/um/os-Linux/registers.c b/arch/x86/um/os-Linux/registers.c index 41bfe84e11ab..00f54a91bb4b 100644 --- a/arch/x86/um/os-Linux/registers.c +++ b/arch/x86/um/os-Linux/registers.c @@ -11,21 +11,56 @@ #endif #include <longjmp.h> #include <sysdep/ptrace_user.h> +#include <sys/uio.h> +#include <asm/sigcontext.h> +#include <linux/elf.h> -int save_fp_registers(int pid, unsigned long *fp_regs) +int have_xstate_support; + +int save_i387_registers(int pid, unsigned long *fp_regs) { if (ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0) return -errno; return 0; } -int restore_fp_registers(int pid, unsigned long *fp_regs) +int save_fp_registers(int pid, unsigned long *fp_regs) +{ + struct iovec iov; + + if (have_xstate_support) { + iov.iov_base = fp_regs; + iov.iov_len = sizeof(struct _xstate); + if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0) + return -errno; + return 0; + } else { + return save_i387_registers(pid, fp_regs); + } +} + +int restore_i387_registers(int pid, unsigned long *fp_regs) { if (ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0) return -errno; return 0; } +int restore_fp_registers(int pid, unsigned long *fp_regs) +{ + struct iovec iov; + + if (have_xstate_support) { + iov.iov_base = fp_regs; + iov.iov_len = sizeof(struct _xstate); + if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0) + return -errno; + return 0; + } else { + return restore_i387_registers(pid, fp_regs); + } +} + #ifdef __i386__ int have_fpx_regs = 1; int save_fpx_registers(int pid, unsigned long *fp_regs) @@ -85,6 +120,16 @@ int put_fp_registers(int pid, unsigned long *regs) return restore_fp_registers(pid, regs); } +void arch_init_registers(int pid) +{ + struct _xstate fp_regs; + struct iovec iov; + + iov.iov_base = &fp_regs; + iov.iov_len = sizeof(struct _xstate); + if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0) + have_xstate_support = 1; +} #endif unsigned long get_thread_reg(int reg, jmp_buf *buf) |