arch/sparc/kernel/sigutil_32.c
Source file repositories/reference/linux-study-clean/arch/sparc/kernel/sigutil_32.c
File Facts
- System
- Linux kernel
- Corpus path
arch/sparc/kernel/sigutil_32.c- Extension
.c- Size
- 3387 bytes
- Lines
- 130
- Domain
- Architecture Layer
- Bucket
- arch/sparc
- Inferred role
- Architecture Layer: implementation source
- Status
- source implementation candidate
Why This File Exists
CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/kernel.hlinux/types.hlinux/thread_info.hlinux/uaccess.hlinux/sched.hasm/sigcontext.hasm/fpumacro.hasm/ptrace.hasm/switch_to.hsigutil.h
Detected Declarations
function save_fpu_statefunction restore_fpu_statefunction save_rwin_statefunction restore_rwin_state
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/thread_info.h>
#include <linux/uaccess.h>
#include <linux/sched.h>
#include <asm/sigcontext.h>
#include <asm/fpumacro.h>
#include <asm/ptrace.h>
#include <asm/switch_to.h>
#include "sigutil.h"
int save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
int err = 0;
#ifdef CONFIG_SMP
if (test_tsk_thread_flag(current, TIF_USEDFPU)) {
put_psr(get_psr() | PSR_EF);
fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
regs->psr &= ~(PSR_EF);
clear_tsk_thread_flag(current, TIF_USEDFPU);
}
#else
if (current == last_task_used_math) {
put_psr(get_psr() | PSR_EF);
fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
last_task_used_math = NULL;
regs->psr &= ~(PSR_EF);
}
#endif
err |= __copy_to_user(&fpu->si_float_regs[0],
¤t->thread.float_regs[0],
(sizeof(unsigned long) * 32));
err |= __put_user(current->thread.fsr, &fpu->si_fsr);
err |= __put_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
if (current->thread.fpqdepth != 0)
err |= __copy_to_user(&fpu->si_fpqueue[0],
¤t->thread.fpqueue[0],
((sizeof(unsigned long) +
(sizeof(unsigned long *)))*16));
clear_used_math();
return err;
}
int restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
int err;
if (((unsigned long) fpu) & 3)
return -EFAULT;
#ifdef CONFIG_SMP
if (test_tsk_thread_flag(current, TIF_USEDFPU))
regs->psr &= ~PSR_EF;
#else
if (current == last_task_used_math) {
last_task_used_math = NULL;
regs->psr &= ~PSR_EF;
}
#endif
set_used_math();
clear_tsk_thread_flag(current, TIF_USEDFPU);
if (!access_ok(fpu, sizeof(*fpu)))
return -EFAULT;
err = __copy_from_user(¤t->thread.float_regs[0], &fpu->si_float_regs[0],
(sizeof(unsigned long) * 32));
err |= __get_user(current->thread.fsr, &fpu->si_fsr);
err |= __get_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
if (current->thread.fpqdepth != 0)
err |= __copy_from_user(¤t->thread.fpqueue[0],
&fpu->si_fpqueue[0],
((sizeof(unsigned long) +
(sizeof(unsigned long *)))*16));
return err;
}
int save_rwin_state(int wsaved, __siginfo_rwin_t __user *rwin)
{
int i, err = __put_user(wsaved, &rwin->wsaved);
for (i = 0; i < wsaved; i++) {
struct reg_window32 *rp;
unsigned long fp;
Annotation
- Immediate include surface: `linux/kernel.h`, `linux/types.h`, `linux/thread_info.h`, `linux/uaccess.h`, `linux/sched.h`, `asm/sigcontext.h`, `asm/fpumacro.h`, `asm/ptrace.h`.
- Detected declarations: `function save_fpu_state`, `function restore_fpu_state`, `function save_rwin_state`, `function restore_rwin_state`.
- Atlas domain: Architecture Layer / arch/sparc.
- Implementation status: source implementation candidate.
- This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.