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author | Suresh Siddha <suresh.b.siddha@intel.com> | 2010-02-22 14:51:33 -0800 |
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committer | H. Peter Anvin <hpa@zytor.com> | 2010-02-23 13:45:27 -0800 |
commit | ff7fbc72e0c3ef7e94a27a3a918fd09ec9a30204 (patch) | |
tree | 1e07cfb9d41d8c7c155ae781f901e287f3833273 /arch/x86/kernel/i387.c | |
parent | c6a0dd7ec6fb2d4927979ed4dc562fc5c122d826 (diff) | |
download | op-kernel-dev-ff7fbc72e0c3ef7e94a27a3a918fd09ec9a30204.zip op-kernel-dev-ff7fbc72e0c3ef7e94a27a3a918fd09ec9a30204.tar.gz |
x86, ptrace: Simplify xstateregs_get()
48 bytes (bytes 464..511) of the xstateregs payload come from the
kernel defined structure (xstate_fx_sw_bytes). Rest comes from the
xstate regs structure in the thread struct. Instead of having multiple
user_regset_copyout()'s, simplify the xstateregs_get() by first
copying the SW bytes into the xstate regs structure in the thread structure
and then using one user_regset_copyout() to copyout the xstateregs.
Requested-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20100222225240.494688491@sbs-t61.sc.intel.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Diffstat (limited to 'arch/x86/kernel/i387.c')
-rw-r--r-- | arch/x86/kernel/i387.c | 30 |
1 files changed, 7 insertions, 23 deletions
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index 7a8a193..81e23bf 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -243,34 +243,18 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset, return ret; /* - * First copy the fxsave bytes 0..463. + * Copy the 48bytes defined by the software first into the xstate + * memory layout in the thread struct, so that we can copy the entire + * xstateregs to the user using one user_regset_copyout(). */ - ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->xsave, 0, - offsetof(struct user_xstateregs, - i387.xstate_fx_sw)); - if (ret) - return ret; - - /* - * Copy the 48bytes defined by software. - */ - ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, - xstate_fx_sw_bytes, - offsetof(struct user_xstateregs, - i387.xstate_fx_sw), - offsetof(struct user_xstateregs, - xsave_hdr)); - if (ret) - return ret; + memcpy(&target->thread.xstate->fxsave.sw_reserved, + xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes)); /* - * Copy the rest of xstate memory layout. + * Copy the xstate memory layout. */ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->xsave.xsave_hdr, - offsetof(struct user_xstateregs, - xsave_hdr), -1); + &target->thread.xstate->xsave, 0, -1); return ret; } |