Have all the functions finding xstate address take a struct fpu * pointer in preparation for dynamic state buffer support.
init_fpstate is a special case, which is indicated by a null pointer parameter to get_xsave_addr() and __raw_xsave_addr(). No functional change. Signed-off-by: Chang S. Bae <chang.seok....@intel.com> Reviewed-by: Len Brown <len.br...@intel.com> Cc: x...@kernel.org Cc: linux-kernel@vger.kernel.org Cc: k...@vger.kernel.org --- Changes from v3: * Updated the changelog. (Borislav Petkov) * Updated the function comment to use kernel-doc style. (Borislav Petkov) Changes from v2: * Updated the changelog with task->fpu removed. (Borislav Petkov) Changes from v1: * Rebased on the upstream kernel (5.10) --- arch/x86/include/asm/fpu/internal.h | 2 +- arch/x86/include/asm/fpu/xstate.h | 2 +- arch/x86/include/asm/pgtable.h | 2 +- arch/x86/kernel/cpu/common.c | 2 +- arch/x86/kernel/fpu/xstate.c | 38 +++++++++++++++++++++-------- arch/x86/kvm/x86.c | 10 +++----- arch/x86/mm/pkeys.c | 2 +- 7 files changed, 37 insertions(+), 21 deletions(-) diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index d81d8c407dc0..0153c4d4ca77 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -579,7 +579,7 @@ static inline void switch_fpu_finish(struct fpu *new_fpu) * return to userland e.g. for a copy_to_user() operation. */ if (current->mm) { - pk = get_xsave_addr(&new_fpu->state.xsave, XFEATURE_PKRU); + pk = get_xsave_addr(new_fpu, XFEATURE_PKRU); if (pk) pkru_val = pk->pkru; } diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index e0f1b22f53ce..24bf8d3f559a 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -100,7 +100,7 @@ extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; extern void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask); -void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr); +void *get_xsave_addr(struct fpu *fpu, int xfeature_nr); const void *get_xsave_field_ptr(int xfeature_nr); int using_compacted_format(void); int xfeature_size(int xfeature_nr); diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index a02c67291cfc..83268b41444f 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -141,7 +141,7 @@ static inline void write_pkru(u32 pkru) if (!boot_cpu_has(X86_FEATURE_OSPKE)) return; - pk = get_xsave_addr(¤t->thread.fpu.state.xsave, XFEATURE_PKRU); + pk = get_xsave_addr(¤t->thread.fpu, XFEATURE_PKRU); /* * The PKRU value in xstate needs to be in sync with the value that is diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 35ad8480c464..860b19db208b 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -478,7 +478,7 @@ static __always_inline void setup_pku(struct cpuinfo_x86 *c) return; cr4_set_bits(X86_CR4_PKE); - pk = get_xsave_addr(&init_fpstate.xsave, XFEATURE_PKRU); + pk = get_xsave_addr(NULL, XFEATURE_PKRU); if (pk) pk->pkru = init_pkru_value; /* diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 6156dad0feb6..5401a71dd15e 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -894,15 +894,24 @@ void fpu__resume_cpu(void) * Given an xstate feature nr, calculate where in the xsave * buffer the state is. Callers should ensure that the buffer * is valid. + * + * @fpu: If NULL, use init_fpstate */ -static void *__raw_xsave_addr(struct xregs_state *xsave, int xfeature_nr) +static void *__raw_xsave_addr(struct fpu *fpu, int xfeature_nr) { + void *xsave; + if (!xfeature_enabled(xfeature_nr)) { WARN_ON_FPU(1); return NULL; } - return (void *)xsave + xstate_comp_offsets[xfeature_nr]; + if (fpu) + xsave = &fpu->state.xsave; + else + xsave = &init_fpstate.xsave; + + return xsave + xstate_comp_offsets[xfeature_nr]; } /* * Given the xsave area and a state inside, this function returns the @@ -915,15 +924,18 @@ static void *__raw_xsave_addr(struct xregs_state *xsave, int xfeature_nr) * this will return NULL. * * Inputs: - * xstate: the thread's storage area for all FPU data + * fpu: the thread's FPU data to reference xstate buffer(s). + * (A null pointer parameter indicates init_fpstate.) * xfeature_nr: state which is defined in xsave.h (e.g. XFEATURE_FP, * XFEATURE_SSE, etc...) * Output: * address of the state in the xsave area, or NULL if the * field is not present in the xsave buffer. */ -void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr) +void *get_xsave_addr(struct fpu *fpu, int xfeature_nr) { + struct xregs_state *xsave; + /* * Do we even *have* xsave state? */ @@ -936,6 +948,12 @@ void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr) */ WARN_ONCE(!(xfeatures_mask_all & BIT_ULL(xfeature_nr)), "get of unsupported state"); + + if (fpu) + xsave = &fpu->state.xsave; + else + xsave = &init_fpstate.xsave; + /* * This assumes the last 'xsave*' instruction to * have requested that 'xfeature_nr' be saved. @@ -950,7 +968,7 @@ void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr) if (!(xsave->header.xfeatures & BIT_ULL(xfeature_nr))) return NULL; - return __raw_xsave_addr(xsave, xfeature_nr); + return __raw_xsave_addr(fpu, xfeature_nr); } EXPORT_SYMBOL_GPL(get_xsave_addr); @@ -981,7 +999,7 @@ const void *get_xsave_field_ptr(int xfeature_nr) */ fpu__save(fpu); - return get_xsave_addr(&fpu->state.xsave, xfeature_nr); + return get_xsave_addr(fpu, xfeature_nr); } #ifdef CONFIG_ARCH_HAS_PKEYS @@ -1116,7 +1134,7 @@ void copy_xstate_to_kernel(struct membuf to, struct fpu *fpu) * Copy only in-use xstates: */ if ((header.xfeatures >> i) & 1) { - void *src = __raw_xsave_addr(xsave, i); + void *src = __raw_xsave_addr(fpu, i); copy_part(&to, &last, xstate_offsets[i], xstate_sizes[i], src); @@ -1151,7 +1169,7 @@ int copy_kernel_to_xstate(struct fpu *fpu, const void *kbuf) u64 mask = ((u64)1 << i); if (hdr.xfeatures & mask) { - void *dst = __raw_xsave_addr(xsave, i); + void *dst = __raw_xsave_addr(fpu, i); offset = xstate_offsets[i]; size = xstate_sizes[i]; @@ -1208,7 +1226,7 @@ int copy_user_to_xstate(struct fpu *fpu, const void __user *ubuf) u64 mask = ((u64)1 << i); if (hdr.xfeatures & mask) { - void *dst = __raw_xsave_addr(xsave, i); + void *dst = __raw_xsave_addr(fpu, i); offset = xstate_offsets[i]; size = xstate_sizes[i]; @@ -1450,7 +1468,7 @@ void update_pasid(void) */ xsave = &fpu->state.xsave; xsave->header.xfeatures |= XFEATURE_MASK_PASID; - ppasid_state = get_xsave_addr(xsave, XFEATURE_PASID); + ppasid_state = get_xsave_addr(fpu, XFEATURE_PASID); /* * Since XFEATURE_MASK_PASID is set in xfeatures, ppasid_state * won't be NULL and no need to check its value. diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b933d005d45e..cc3b604ddcd2 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4461,7 +4461,7 @@ static void fill_xsave(u8 *dest, struct kvm_vcpu *vcpu) while (valid) { u64 xfeature_mask = valid & -valid; int xfeature_nr = fls64(xfeature_mask) - 1; - void *src = get_xsave_addr(xsave, xfeature_nr); + void *src = get_xsave_addr(vcpu->arch.guest_fpu, xfeature_nr); if (src) { u32 size, offset, ecx, edx; @@ -4504,7 +4504,7 @@ static void load_xsave(struct kvm_vcpu *vcpu, u8 *src) while (valid) { u64 xfeature_mask = valid & -valid; int xfeature_nr = fls64(xfeature_mask) - 1; - void *dest = get_xsave_addr(xsave, xfeature_nr); + void *dest = get_xsave_addr(vcpu->arch.guest_fpu, xfeature_nr); if (dest) { u32 size, offset, ecx, edx; @@ -10140,12 +10140,10 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) */ if (init_event) kvm_put_guest_fpu(vcpu); - mpx_state_buffer = get_xsave_addr(&vcpu->arch.guest_fpu->state.xsave, - XFEATURE_BNDREGS); + mpx_state_buffer = get_xsave_addr(vcpu->arch.guest_fpu, XFEATURE_BNDREGS); if (mpx_state_buffer) memset(mpx_state_buffer, 0, sizeof(struct mpx_bndreg_state)); - mpx_state_buffer = get_xsave_addr(&vcpu->arch.guest_fpu->state.xsave, - XFEATURE_BNDCSR); + mpx_state_buffer = get_xsave_addr(vcpu->arch.guest_fpu, XFEATURE_BNDCSR); if (mpx_state_buffer) memset(mpx_state_buffer, 0, sizeof(struct mpx_bndcsr)); if (init_event) diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c index 8873ed1438a9..772e8bc3d49d 100644 --- a/arch/x86/mm/pkeys.c +++ b/arch/x86/mm/pkeys.c @@ -177,7 +177,7 @@ static ssize_t init_pkru_write_file(struct file *file, return -EINVAL; WRITE_ONCE(init_pkru_value, new_init_pkru); - pk = get_xsave_addr(&init_fpstate.xsave, XFEATURE_PKRU); + pk = get_xsave_addr(NULL, XFEATURE_PKRU); if (!pk) return -EINVAL; pk->pkru = new_init_pkru; -- 2.17.1