diff options
| author | Ian Moffett <ian@osmora.org> | 2024-07-02 21:19:49 -0400 |
|---|---|---|
| committer | Ian Moffett <ian@osmora.org> | 2024-07-02 21:25:53 -0400 |
| commit | 2d7bc823503167276c6d3c40500c3055d4f38938 (patch) | |
| tree | 2971c86e108f5afa1c622afa511a289d12e7a3e6 /sys/include | |
| parent | 52760e9c5e677b76c81e921bbab95da26478f425 (diff) | |
kernel/amd64: Handle the user GS segment register
This commit introduces usage of swapgs to switch out the GS register
with the user GS register. An md_td_kick() function is also introduced
to start up user threads. The this_cpu() function uses the GS register
to read the current CPU structure using a new "self" field.
Signed-off-by: Ian Moffett <ian@osmora.org>
Diffstat (limited to 'sys/include')
| -rw-r--r-- | sys/include/arch/amd64/cpu.h | 1 | ||||
| -rw-r--r-- | sys/include/arch/amd64/frameasm.h | 24 | ||||
| -rw-r--r-- | sys/include/sys/proc.h | 2 |
3 files changed, 23 insertions, 4 deletions
diff --git a/sys/include/arch/amd64/cpu.h b/sys/include/arch/amd64/cpu.h index 16936e9..2ce363c 100644 --- a/sys/include/arch/amd64/cpu.h +++ b/sys/include/arch/amd64/cpu.h @@ -42,6 +42,7 @@ struct cpu_info { size_t lapic_tmr_freq; struct tss_entry *tss; struct proc *curtd; + struct cpu_info *self; }; void cpu_startup(struct cpu_info *ci); diff --git a/sys/include/arch/amd64/frameasm.h b/sys/include/arch/amd64/frameasm.h index b8791ba..8983d36 100644 --- a/sys/include/arch/amd64/frameasm.h +++ b/sys/include/arch/amd64/frameasm.h @@ -106,11 +106,19 @@ */ #define INTRENTRY(ENTLABEL, HANDLER) \ ENTLABEL: \ - push_trapframe $0 ; \ + testq $0x3, 8(%rsp) ; \ + jz 1f ; \ + lfence ; \ + swapgs ; \ + 1: push_trapframe $0 ; \ mov %rsp, %rdi ; \ call HANDLER ; \ pop_trapframe ; \ - iretq + testq $0x3, 8(%rsp) ; \ + jz 2f ; \ + lfence ; \ + swapgs ; \ + 2: iretq /* * Trap entry where an error code is on @@ -118,10 +126,18 @@ */ #define TRAPENTRY(ENTLABEL, TRAPNO) \ ENTLABEL: \ - push_trapframe_ec TRAPNO ; \ + testq $0x3, 8(%rsp) ; \ + jz 1f ; \ + lfence ; \ + swapgs ; \ + 1: push_trapframe_ec TRAPNO ; \ mov %rsp, %rdi ; \ call trap_handler ; \ pop_trapframe_ec ; \ - iretq + testq $0x3, 8(%rsp) ; \ + jz 2f ; \ + lfence ; \ + swapgs ; \ + 2: iretq #endif /* !_MACHINE_FRAMEASM_H_ */ diff --git a/sys/include/sys/proc.h b/sys/include/sys/proc.h index ba931f3..805c4a5 100644 --- a/sys/include/sys/proc.h +++ b/sys/include/sys/proc.h @@ -34,6 +34,7 @@ #include <sys/spinlock.h> #include <sys/queue.h> #include <sys/param.h> +#include <sys/cdefs.h> #if defined(_KERNEL) #include <machine/frame.h> #include <machine/pcb.h> @@ -63,6 +64,7 @@ struct proc *this_td(void); int md_fork(struct proc *p, struct proc *parent, uintptr_t ip); void md_td_stackinit(struct proc *td, void *stack_top, struct exec_prog *prog); +__dead void md_td_kick(struct proc *td); int fork1(struct proc *cur, int flags, void(*ip)(void), struct proc **newprocp); int exit1(struct proc *td); |