x86: switch to ->regset_get()
authorAl Viro <viro@zeniv.linux.org.uk>
Tue, 18 Feb 2020 17:14:34 +0000 (12:14 -0500)
committerAl Viro <viro@zeniv.linux.org.uk>
Mon, 27 Jul 2020 18:31:07 +0000 (14:31 -0400)
All instances of ->get() in arch/x86 switched; that might or might
not be worth splitting up.  Notes:

* for xstateregs_get() the amount we want to store is determined at
the boot time; see init_xstate_size() and update_regset_xstate_info() for
details.  task->thread.fpu.state.xsave ends with a flexible array member and
the amount of data in it depends upon the FPU features supported/enabled.

* fpregs_get() writes slightly less than full ->thread.fpu.state.fsave
(the last word is not copied); we pass the full size of state.fsave and let
membuf_write() trim to the amount declared by regset - __regset_get() will
make sure that the space in buffer is no more than that.

* copy_xstate_to_user() and its helpers are gone now.

* fpregs_soft_get() was getting user_regset_copyout() arguments
wrong.  Since "x86: x86 user_regset math_emu" back in 2008...  I really
doubt that it's worth splitting out for -stable, though - you need
a 486SX box for that to trigger...

[Kevin's braino fix for copy_xstate_to_kernel() essentially duplicated here]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
arch/x86/include/asm/fpu/regset.h
arch/x86/include/asm/fpu/xstate.h
arch/x86/kernel/fpu/regset.c
arch/x86/kernel/fpu/signal.c
arch/x86/kernel/fpu/xstate.c
arch/x86/kernel/ptrace.c
arch/x86/kernel/tls.c
arch/x86/kernel/tls.h
arch/x86/math-emu/fpu_entry.c

index d5bdffb..4f928d6 100644 (file)
@@ -8,8 +8,8 @@
 #include <linux/regset.h>
 
 extern user_regset_active_fn regset_fpregs_active, regset_xregset_fpregs_active;
-extern user_regset_get_fn fpregs_get, xfpregs_get, fpregs_soft_get,
-                               xstateregs_get;
+extern user_regset_get2_fn fpregs_get, xfpregs_get, fpregs_soft_get,
+                                xstateregs_get;
 extern user_regset_set_fn fpregs_set, xfpregs_set, fpregs_soft_set,
                                 xstateregs_set;
 
index 422d836..f691ea1 100644 (file)
@@ -71,8 +71,8 @@ extern void __init update_regset_xstate_info(unsigned int size,
 void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
 const void *get_xsave_field_ptr(int xfeature_nr);
 int using_compacted_format(void);
-int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int offset, unsigned int size);
-int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned int offset, unsigned int size);
+struct membuf;
+void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave);
 int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
 int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
 void copy_supervisor_to_kernel(struct xregs_state *xsave);
index 91f80ac..c413756 100644 (file)
@@ -27,8 +27,7 @@ int regset_xregset_fpregs_active(struct task_struct *target, const struct user_r
 }
 
 int xfpregs_get(struct task_struct *target, const struct user_regset *regset,
-               unsigned int pos, unsigned int count,
-               void *kbuf, void __user *ubuf)
+               struct membuf to)
 {
        struct fpu *fpu = &target->thread.fpu;
 
@@ -38,8 +37,7 @@ int xfpregs_get(struct task_struct *target, const struct user_regset *regset,
        fpu__prepare_read(fpu);
        fpstate_sanitize_xstate(fpu);
 
-       return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-                                  &fpu->state.fxsave, 0, -1);
+       return membuf_write(&to, &fpu->state.fxsave, sizeof(struct fxregs_state));
 }
 
 int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
@@ -74,12 +72,10 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
 }
 
 int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
-               unsigned int pos, unsigned int count,
-               void *kbuf, void __user *ubuf)
+               struct membuf to)
 {
        struct fpu *fpu = &target->thread.fpu;
        struct xregs_state *xsave;
-       int ret;
 
        if (!boot_cpu_has(X86_FEATURE_XSAVE))
                return -ENODEV;
@@ -89,10 +85,8 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
        fpu__prepare_read(fpu);
 
        if (using_compacted_format()) {
-               if (kbuf)
-                       ret = copy_xstate_to_kernel(kbuf, xsave, pos, count);
-               else
-                       ret = copy_xstate_to_user(ubuf, xsave, pos, count);
+               copy_xstate_to_kernel(to, xsave);
+               return 0;
        } else {
                fpstate_sanitize_xstate(fpu);
                /*
@@ -105,9 +99,8 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
                /*
                 * Copy the xstate memory layout.
                 */
-               ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, xsave, 0, -1);
+               return membuf_write(&to, xsave, fpu_user_xstate_size);
        }
-       return ret;
 }
 
 int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
@@ -293,8 +286,7 @@ void convert_to_fxsr(struct fxregs_state *fxsave,
 }
 
 int fpregs_get(struct task_struct *target, const struct user_regset *regset,
-              unsigned int pos, unsigned int count,
-              void *kbuf, void __user *ubuf)
+              struct membuf to)
 {
        struct fpu *fpu = &target->thread.fpu;
        struct user_i387_ia32_struct env;
@@ -302,23 +294,22 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset,
        fpu__prepare_read(fpu);
 
        if (!boot_cpu_has(X86_FEATURE_FPU))
-               return fpregs_soft_get(target, regset, pos, count, kbuf, ubuf);
+               return fpregs_soft_get(target, regset, to);
 
-       if (!boot_cpu_has(X86_FEATURE_FXSR))
-               return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-                                          &fpu->state.fsave, 0,
-                                          -1);
+       if (!boot_cpu_has(X86_FEATURE_FXSR)) {
+               return membuf_write(&to, &fpu->state.fsave,
+                                   sizeof(struct fregs_state));
+       }
 
        fpstate_sanitize_xstate(fpu);
 
-       if (kbuf && pos == 0 && count == sizeof(env)) {
-               convert_from_fxsr(kbuf, target);
+       if (to.left == sizeof(env)) {
+               convert_from_fxsr(to.p, target);
                return 0;
        }
 
        convert_from_fxsr(&env, target);
-
-       return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1);
+       return membuf_write(&to, &env, sizeof(env));
 }
 
 int fpregs_set(struct task_struct *target, const struct user_regset *regset,
index e0b832d..a4ec653 100644 (file)
@@ -172,7 +172,8 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size)
 
        if (!static_cpu_has(X86_FEATURE_FPU)) {
                struct user_i387_ia32_struct fp;
-               fpregs_soft_get(current, NULL, 0, sizeof(fp), &fp, NULL);
+               fpregs_soft_get(current, NULL, (struct membuf){.p = &fp,
+                                               .left = sizeof(fp)});
                return copy_to_user(buf, &fp, sizeof(fp)) ? -EFAULT : 0;
        }
 
index bda2e5e..4f8e428 100644 (file)
@@ -1009,32 +1009,20 @@ static inline bool xfeatures_mxcsr_quirk(u64 xfeatures)
        return true;
 }
 
-static void fill_gap(unsigned to, void **kbuf, unsigned *pos, unsigned *count)
+static void fill_gap(struct membuf *to, unsigned *last, unsigned offset)
 {
-       if (*pos < to) {
-               unsigned size = to - *pos;
-
-               if (size > *count)
-                       size = *count;
-               memcpy(*kbuf, (void *)&init_fpstate.xsave + *pos, size);
-               *kbuf += size;
-               *pos += size;
-               *count -= size;
-       }
+       if (*last >= offset)
+               return;
+       membuf_write(to, (void *)&init_fpstate.xsave + *last, offset - *last);
+       *last = offset;
 }
 
-static void copy_part(unsigned offset, unsigned size, void *from,
-                       void **kbuf, unsigned *pos, unsigned *count)
+static void copy_part(struct membuf *to, unsigned *last, unsigned offset,
+                     unsigned size, void *from)
 {
-       fill_gap(offset, kbuf, pos, count);
-       if (size > *count)
-               size = *count;
-       if (size) {
-               memcpy(*kbuf, from, size);
-               *kbuf += size;
-               *pos += size;
-               *count -= size;
-       }
+       fill_gap(to, last, offset);
+       membuf_write(to, from, size);
+       *last = offset + size;
 }
 
 /*
@@ -1044,19 +1032,14 @@ static void copy_part(unsigned offset, unsigned size, void *from,
  * It supports partial copy but pos always starts from zero. This is called
  * from xstateregs_get() and there we check the CPU has XSAVES.
  */
-int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int offset_start, unsigned int size_total)
+void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave)
 {
        struct xstate_header header;
        const unsigned off_mxcsr = offsetof(struct fxregs_state, mxcsr);
-       unsigned count = size_total;
+       unsigned size = to.left;
+       unsigned last = 0;
        int i;
 
-       /*
-        * Currently copy_regset_to_user() starts from pos 0:
-        */
-       if (unlikely(offset_start != 0))
-               return -EFAULT;
-
        /*
         * The destination is a ptrace buffer; we put in only user xstates:
         */
@@ -1065,27 +1048,26 @@ int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int of
        header.xfeatures &= xfeatures_mask_user();
 
        if (header.xfeatures & XFEATURE_MASK_FP)
-               copy_part(0, off_mxcsr,
-                         &xsave->i387, &kbuf, &offset_start, &count);
+               copy_part(&to, &last, 0, off_mxcsr, &xsave->i387);
        if (header.xfeatures & (XFEATURE_MASK_SSE | XFEATURE_MASK_YMM))
-               copy_part(off_mxcsr, MXCSR_AND_FLAGS_SIZE,
-                         &xsave->i387.mxcsr, &kbuf, &offset_start, &count);
+               copy_part(&to, &last, off_mxcsr,
+                         MXCSR_AND_FLAGS_SIZE, &xsave->i387.mxcsr);
        if (header.xfeatures & XFEATURE_MASK_FP)
-               copy_part(offsetof(struct fxregs_state, st_space), 128,
-                         &xsave->i387.st_space, &kbuf, &offset_start, &count);
+               copy_part(&to, &last, offsetof(struct fxregs_state, st_space),
+                         128, &xsave->i387.st_space);
        if (header.xfeatures & XFEATURE_MASK_SSE)
-               copy_part(xstate_offsets[XFEATURE_MASK_SSE], 256,
-                         &xsave->i387.xmm_space, &kbuf, &offset_start, &count);
+               copy_part(&to, &last, xstate_offsets[XFEATURE_SSE],
+                         256, &xsave->i387.xmm_space);
        /*
         * Fill xsave->i387.sw_reserved value for ptrace frame:
         */
-       copy_part(offsetof(struct fxregs_state, sw_reserved), 48,
-                 xstate_fx_sw_bytes, &kbuf, &offset_start, &count);
+       copy_part(&to, &last, offsetof(struct fxregs_state, sw_reserved),
+                 48, xstate_fx_sw_bytes);
        /*
         * Copy xregs_state->header:
         */
-       copy_part(offsetof(struct xregs_state, header), sizeof(header),
-                 &header, &kbuf, &offset_start, &count);
+       copy_part(&to, &last, offsetof(struct xregs_state, header),
+                 sizeof(header), &header);
 
        for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) {
                /*
@@ -1094,104 +1076,12 @@ int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int of
                if ((header.xfeatures >> i) & 1) {
                        void *src = __raw_xsave_addr(xsave, i);
 
-                       copy_part(xstate_offsets[i], xstate_sizes[i],
-                                 src, &kbuf, &offset_start, &count);
+                       copy_part(&to, &last, xstate_offsets[i],
+                                 xstate_sizes[i], src);
                }
 
        }
-       fill_gap(size_total, &kbuf, &offset_start, &count);
-
-       return 0;
-}
-
-static inline int
-__copy_xstate_to_user(void __user *ubuf, const void *data, unsigned int offset, unsigned int size, unsigned int size_total)
-{
-       if (!size)
-               return 0;
-
-       if (offset < size_total) {
-               unsigned int copy = min(size, size_total - offset);
-
-               if (__copy_to_user(ubuf + offset, data, copy))
-                       return -EFAULT;
-       }
-       return 0;
-}
-
-/*
- * Convert from kernel XSAVES compacted format to standard format and copy
- * to a user-space buffer. It supports partial copy but pos always starts from
- * zero. This is called from xstateregs_get() and there we check the CPU
- * has XSAVES.
- */
-int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned int offset_start, unsigned int size_total)
-{
-       unsigned int offset, size;
-       int ret, i;
-       struct xstate_header header;
-
-       /*
-        * Currently copy_regset_to_user() starts from pos 0:
-        */
-       if (unlikely(offset_start != 0))
-               return -EFAULT;
-
-       /*
-        * The destination is a ptrace buffer; we put in only user xstates:
-        */
-       memset(&header, 0, sizeof(header));
-       header.xfeatures = xsave->header.xfeatures;
-       header.xfeatures &= xfeatures_mask_user();
-
-       /*
-        * Copy xregs_state->header:
-        */
-       offset = offsetof(struct xregs_state, header);
-       size = sizeof(header);
-
-       ret = __copy_xstate_to_user(ubuf, &header, offset, size, size_total);
-       if (ret)
-               return ret;
-
-       for (i = 0; i < XFEATURE_MAX; i++) {
-               /*
-                * Copy only in-use xstates:
-                */
-               if ((header.xfeatures >> i) & 1) {
-                       void *src = __raw_xsave_addr(xsave, i);
-
-                       offset = xstate_offsets[i];
-                       size = xstate_sizes[i];
-
-                       /* The next component has to fit fully into the output buffer: */
-                       if (offset + size > size_total)
-                               break;
-
-                       ret = __copy_xstate_to_user(ubuf, src, offset, size, size_total);
-                       if (ret)
-                               return ret;
-               }
-
-       }
-
-       if (xfeatures_mxcsr_quirk(header.xfeatures)) {
-               offset = offsetof(struct fxregs_state, mxcsr);
-               size = MXCSR_AND_FLAGS_SIZE;
-               __copy_xstate_to_user(ubuf, &xsave->i387.mxcsr, offset, size, size_total);
-       }
-
-       /*
-        * Fill xsave->i387.sw_reserved value for ptrace frame:
-        */
-       offset = offsetof(struct fxregs_state, sw_reserved);
-       size = sizeof(xstate_fx_sw_bytes);
-
-       ret = __copy_xstate_to_user(ubuf, xstate_fx_sw_bytes, offset, size, size_total);
-       if (ret)
-               return ret;
-
-       return 0;
+       fill_gap(&to, &last, size);
 }
 
 /*
index 4413058..8413cb1 100644 (file)
@@ -433,26 +433,12 @@ static unsigned long getreg(struct task_struct *task, unsigned long offset)
 
 static int genregs_get(struct task_struct *target,
                       const struct user_regset *regset,
-                      unsigned int pos, unsigned int count,
-                      void *kbuf, void __user *ubuf)
+                      struct membuf to)
 {
-       if (kbuf) {
-               unsigned long *k = kbuf;
-               while (count >= sizeof(*k)) {
-                       *k++ = getreg(target, pos);
-                       count -= sizeof(*k);
-                       pos += sizeof(*k);
-               }
-       } else {
-               unsigned long __user *u = ubuf;
-               while (count >= sizeof(*u)) {
-                       if (__put_user(getreg(target, pos), u++))
-                               return -EFAULT;
-                       count -= sizeof(*u);
-                       pos += sizeof(*u);
-               }
-       }
+       int reg;
 
+       for (reg = 0; to.left; reg++)
+               membuf_store(&to, getreg(target, reg * sizeof(unsigned long)));
        return 0;
 }
 
@@ -716,16 +702,14 @@ static int ioperm_active(struct task_struct *target,
 
 static int ioperm_get(struct task_struct *target,
                      const struct user_regset *regset,
-                     unsigned int pos, unsigned int count,
-                     void *kbuf, void __user *ubuf)
+                     struct membuf to)
 {
        struct io_bitmap *iobm = target->thread.io_bitmap;
 
        if (!iobm)
                return -ENXIO;
 
-       return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-                                  iobm->bitmap, 0, IO_BITMAP_BYTES);
+       return membuf_write(&to, iobm->bitmap, IO_BITMAP_BYTES);
 }
 
 /*
@@ -1003,28 +987,15 @@ static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
 
 static int genregs32_get(struct task_struct *target,
                         const struct user_regset *regset,
-                        unsigned int pos, unsigned int count,
-                        void *kbuf, void __user *ubuf)
+                        struct membuf to)
 {
-       if (kbuf) {
-               compat_ulong_t *k = kbuf;
-               while (count >= sizeof(*k)) {
-                       getreg32(target, pos, k++);
-                       count -= sizeof(*k);
-                       pos += sizeof(*k);
-               }
-       } else {
-               compat_ulong_t __user *u = ubuf;
-               while (count >= sizeof(*u)) {
-                       compat_ulong_t word;
-                       getreg32(target, pos, &word);
-                       if (__put_user(word, u++))
-                               return -EFAULT;
-                       count -= sizeof(*u);
-                       pos += sizeof(*u);
-               }
-       }
+       int reg;
 
+       for (reg = 0; to.left; reg++) {
+               u32 val;
+               getreg32(target, reg * 4, &val);
+               membuf_store(&to, val);
+       }
        return 0;
 }
 
@@ -1234,25 +1205,25 @@ static struct user_regset x86_64_regsets[] __ro_after_init = {
                .core_note_type = NT_PRSTATUS,
                .n = sizeof(struct user_regs_struct) / sizeof(long),
                .size = sizeof(long), .align = sizeof(long),
-               .get = genregs_get, .set = genregs_set
+               .regset_get = genregs_get, .set = genregs_set
        },
        [REGSET_FP] = {
                .core_note_type = NT_PRFPREG,
                .n = sizeof(struct user_i387_struct) / sizeof(long),
                .size = sizeof(long), .align = sizeof(long),
-               .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
+               .active = regset_xregset_fpregs_active, .regset_get = xfpregs_get, .set = xfpregs_set
        },
        [REGSET_XSTATE] = {
                .core_note_type = NT_X86_XSTATE,
                .size = sizeof(u64), .align = sizeof(u64),
-               .active = xstateregs_active, .get = xstateregs_get,
+               .active = xstateregs_active, .regset_get = xstateregs_get,
                .set = xstateregs_set
        },
        [REGSET_IOPERM64] = {
                .core_note_type = NT_386_IOPERM,
                .n = IO_BITMAP_LONGS,
                .size = sizeof(long), .align = sizeof(long),
-               .active = ioperm_active, .get = ioperm_get
+               .active = ioperm_active, .regset_get = ioperm_get
        },
 };
 
@@ -1275,24 +1246,24 @@ static struct user_regset x86_32_regsets[] __ro_after_init = {
                .core_note_type = NT_PRSTATUS,
                .n = sizeof(struct user_regs_struct32) / sizeof(u32),
                .size = sizeof(u32), .align = sizeof(u32),
-               .get = genregs32_get, .set = genregs32_set
+               .regset_get = genregs32_get, .set = genregs32_set
        },
        [REGSET_FP] = {
                .core_note_type = NT_PRFPREG,
                .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
                .size = sizeof(u32), .align = sizeof(u32),
-               .active = regset_fpregs_active, .get = fpregs_get, .set = fpregs_set
+               .active = regset_fpregs_active, .regset_get = fpregs_get, .set = fpregs_set
        },
        [REGSET_XFP] = {
                .core_note_type = NT_PRXFPREG,
                .n = sizeof(struct user32_fxsr_struct) / sizeof(u32),
                .size = sizeof(u32), .align = sizeof(u32),
-               .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
+               .active = regset_xregset_fpregs_active, .regset_get = xfpregs_get, .set = xfpregs_set
        },
        [REGSET_XSTATE] = {
                .core_note_type = NT_X86_XSTATE,
                .size = sizeof(u64), .align = sizeof(u64),
-               .active = xstateregs_active, .get = xstateregs_get,
+               .active = xstateregs_active, .regset_get = xstateregs_get,
                .set = xstateregs_set
        },
        [REGSET_TLS] = {
@@ -1301,13 +1272,13 @@ static struct user_regset x86_32_regsets[] __ro_after_init = {
                .size = sizeof(struct user_desc),
                .align = sizeof(struct user_desc),
                .active = regset_tls_active,
-               .get = regset_tls_get, .set = regset_tls_set
+               .regset_get = regset_tls_get, .set = regset_tls_set
        },
        [REGSET_IOPERM32] = {
                .core_note_type = NT_386_IOPERM,
                .n = IO_BITMAP_BYTES / sizeof(u32),
                .size = sizeof(u32), .align = sizeof(u32),
-               .active = ioperm_active, .get = ioperm_get
+               .active = ioperm_active, .regset_get = ioperm_get
        },
 };
 
index 71d3fef..64a496a 100644 (file)
@@ -256,36 +256,16 @@ int regset_tls_active(struct task_struct *target,
 }
 
 int regset_tls_get(struct task_struct *target, const struct user_regset *regset,
-                  unsigned int pos, unsigned int count,
-                  void *kbuf, void __user *ubuf)
+                  struct membuf to)
 {
        const struct desc_struct *tls;
+       struct user_desc v;
+       int pos;
 
-       if (pos >= GDT_ENTRY_TLS_ENTRIES * sizeof(struct user_desc) ||
-           (pos % sizeof(struct user_desc)) != 0 ||
-           (count % sizeof(struct user_desc)) != 0)
-               return -EINVAL;
-
-       pos /= sizeof(struct user_desc);
-       count /= sizeof(struct user_desc);
-
-       tls = &target->thread.tls_array[pos];
-
-       if (kbuf) {
-               struct user_desc *info = kbuf;
-               while (count-- > 0)
-                       fill_user_desc(info++, GDT_ENTRY_TLS_MIN + pos++,
-                                      tls++);
-       } else {
-               struct user_desc __user *u_info = ubuf;
-               while (count-- > 0) {
-                       struct user_desc info;
-                       fill_user_desc(&info, GDT_ENTRY_TLS_MIN + pos++, tls++);
-                       if (__copy_to_user(u_info++, &info, sizeof(info)))
-                               return -EFAULT;
-               }
+       for (pos = 0, tls = target->thread.tls_array; to.left; pos++, tls++) {
+               fill_user_desc(&v, GDT_ENTRY_TLS_MIN + pos, tls);
+               membuf_write(&to, &v, sizeof(v));
        }
-
        return 0;
 }
 
index 3a76e1d..fc39447 100644 (file)
@@ -12,7 +12,7 @@
 #include <linux/regset.h>
 
 extern user_regset_active_fn regset_tls_active;
-extern user_regset_get_fn regset_tls_get;
+extern user_regset_get2_fn regset_tls_get;
 extern user_regset_set_fn regset_tls_set;
 
 #endif /* _ARCH_X86_KERNEL_TLS_H */
index a873da6..8679a9d 100644 (file)
@@ -689,12 +689,10 @@ int fpregs_soft_set(struct task_struct *target,
 
 int fpregs_soft_get(struct task_struct *target,
                    const struct user_regset *regset,
-                   unsigned int pos, unsigned int count,
-                   void *kbuf, void __user *ubuf)
+                   struct membuf to)
 {
        struct swregs_state *s387 = &target->thread.fpu.state.soft;
        const void *space = s387->st_space;
-       int ret;
        int offset = (S387->ftop & 7) * 10, other = 80 - offset;
 
        RE_ENTRANT_CHECK_OFF;
@@ -709,18 +707,11 @@ int fpregs_soft_get(struct task_struct *target,
        S387->fos |= 0xffff0000;
 #endif /* PECULIAR_486 */
 
-       ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, s387, 0,
-                                 offsetof(struct swregs_state, st_space));
-
-       /* Copy all registers in stack order. */
-       if (!ret)
-               ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-                                         space + offset, 0, other);
-       if (!ret)
-               ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-                                         space, 0, offset);
+       membuf_write(&to, s387, offsetof(struct swregs_state, st_space));
+       membuf_write(&to, space + offset, other);
+       membuf_write(&to, space, offset);
 
        RE_ENTRANT_CHECK_ON;
 
-       return ret;
+       return 0;
 }