- unsigned int offset, size;
- int i;
- struct xstate_header hdr;
-
- offset = offsetof(struct xregs_state, header);
- size = sizeof(hdr);
-
- if (copy_from_user(&hdr, ubuf + offset, size))
- return -EFAULT;
-
- if (validate_user_xstate_header(&hdr))
- return -EINVAL;
-
- for (i = 0; i < XFEATURE_MAX; i++) {
- u64 mask = ((u64)1 << i);
-
- if (hdr.xfeatures & mask) {
- void *dst = __raw_xsave_addr(xsave, i);
-
- offset = xstate_offsets[i];
- size = xstate_sizes[i];
-
- if (copy_from_user(dst, ubuf + offset, size))
- return -EFAULT;
- }
- }
-
- if (xfeatures_mxcsr_quirk(hdr.xfeatures)) {
- offset = offsetof(struct fxregs_state, mxcsr);
- size = MXCSR_AND_FLAGS_SIZE;
- if (copy_from_user(&xsave->i387.mxcsr, ubuf + offset, size))
- return -EFAULT;
- }
-
- /*
- * The state that came in from userspace was user-state only.
- * Mask all the user states out of 'xfeatures':
- */
- xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR_ALL;
-
- /*
- * Add back in the features that came in from userspace:
- */
- xsave->header.xfeatures |= hdr.xfeatures;
-
- return 0;