| /* See COPYRIGHT for copyright information. */ |
| |
| #pragma once |
| |
| #define ROS_KERN_TRAP_H |
| |
| #include <ros/trapframe.h> |
| #include <arch/arch.h> |
| #include <arch/mmu.h> |
| #include <sys/queue.h> |
| #include <arch/trap.h> |
| |
| // func ptr for interrupt service routines |
| typedef void (*isr_t)(struct hw_trapframe *hw_tf, void *data); |
| |
| void idt_init(void); |
| int register_irq(int irq, isr_t handler, void *irq_arg, uint32_t tbdf); |
| int route_irqs(int cpu_vec, int coreid); |
| void print_trapframe(struct hw_trapframe *hw_tf); |
| void print_swtrapframe(struct sw_trapframe *sw_tf); |
| void print_vmtrapframe(struct vm_trapframe *vm_tf); |
| void print_user_ctx(struct user_context *ctx); |
| /* Generic per-core timer interrupt handler. set_percore_timer() will fire the |
| * timer_interrupt(). */ |
| void set_core_timer(uint32_t usec, bool periodic); |
| void timer_interrupt(struct hw_trapframe *hw_tf, void *data); |
| |
| extern inline void save_fp_state(struct ancillary_state *silly); |
| extern inline void restore_fp_state(struct ancillary_state *silly); |
| extern inline void init_fp_state(void); |
| /* Set stacktop for the current core to be the stack the kernel will start on |
| * when trapping/interrupting from userspace */ |
| void set_stack_top(uintptr_t stacktop); |
| uintptr_t get_stack_top(void); |
| |
| void send_nmi(uint32_t os_coreid); |
| int reflect_current_context(void); |
| void reflect_unhandled_trap(unsigned int trap_nr, unsigned int err, |
| unsigned long aux); |
| void __arch_reflect_trap_hwtf(struct hw_trapframe *hw_tf, unsigned int trap_nr, |
| unsigned int err, unsigned long aux); |
| |
| uintptr_t get_user_ctx_pc(struct user_context *ctx); |
| uintptr_t get_user_ctx_fp(struct user_context *ctx); |
| uintptr_t get_user_ctx_sp(struct user_context *ctx); |
| |
| /* Partial contexts are those where the full context is split between the parts |
| * in the struct and the parts still loaded in hardware. |
| * |
| * Finalizing a context ensures that the full context is saved in the struct and |
| * nothing remains in hardware. Finalize does two things: makes sure the |
| * context can be run again on another core and makes sure the core can run |
| * another context. |
| * |
| * arch_finalize_ctx() must be idempotent and have no effect on a full context. |
| * It is up to the architecture to keep track of whether or not a context is |
| * full or partial and handle finalize calls on a context that might not be |
| * partial. They can do so in the ctx itself, in their own arch-dependent |
| * manner. |
| * |
| * The kernel's guarantee to the arches is that: |
| * - finalize will be called after proc_pop_ctx (i.e. after it runs) at least |
| * once, before that context is used again on another core or before another |
| * context is used on this core. |
| * - the arches can store the partial status and anything else it wants in the |
| * *ctx without fear of it being tampered with. |
| * - user-provided contexts will be passed to proc_secure_ctx, and those |
| * contexts are full/finalized already. Anything else is a user bug. The |
| * arches enforce this. |
| * - an arch will never be asked to pop a partial context that was not already |
| * loaded onto the current core. |
| * - contexts will be finalized before handing them back to the user. */ |
| extern inline void arch_finalize_ctx(struct user_context *ctx); |
| extern inline bool arch_ctx_is_partial(struct user_context *ctx); |
| void copy_current_ctx_to(struct user_context *to_ctx); |
| |
| /* Kernel messages. This is an in-order 'active message' style messaging |
| * subsystem, where you can instruct other cores (including your own) to execute |
| * a function (with arguments), either immediately or whenever the kernel is |
| * able to abandon its context/stack (permanent swap). |
| * |
| * These are different (for now) than the smp_calls in smp.h, since |
| * they will be executed immediately (for urgent messages), and in the order in |
| * which they are sent. smp_calls are currently not run in order, and they must |
| * return (possibly passing the work to a workqueue, which is really just a |
| * routine message, so they really need to just return). |
| * |
| * Eventually, smp_call will be replaced by these. |
| * |
| * Also, a big difference is that smp_calls can use the same message (registered |
| * in the interrupt_handlers[] for x86) for every recipient, but the kernel |
| * messages require a unique message. Also for now, but it might be like that |
| * for a while on x86 (til we have a broadcast). */ |
| |
| #define KMSG_IMMEDIATE 1 |
| #define KMSG_ROUTINE 2 |
| |
| typedef void (*amr_t)(uint32_t srcid, long a0, long a1, long a2); |
| |
| struct kernel_message |
| { |
| STAILQ_ENTRY(kernel_message) link; |
| uint32_t srcid; |
| uint32_t dstid; |
| amr_t pc; |
| long arg0; |
| long arg1; |
| long arg2; |
| }__attribute__((aligned(8))); |
| |
| STAILQ_HEAD(kernel_msg_list, kernel_message); |
| typedef struct kernel_message kernel_message_t; |
| |
| void kernel_msg_init(void); |
| uint32_t send_kernel_message(uint32_t dst, amr_t pc, long arg0, long arg1, |
| long arg2, int type); |
| void handle_kmsg_ipi(struct hw_trapframe *hw_tf, void *data); |
| bool has_routine_kmsg(void); |
| void process_routine_kmsg(void); |
| void print_kmsgs(uint32_t coreid); |
| |
| /* Runs a function with up to two arguments as a routine kernel message. Kernel |
| * messages can have three arguments, but the deferred function pointer counts |
| * as one. Note the arguments to the function will be treated as longs. */ |
| #define run_as_rkm(f, ...) do { \ |
| static_assert(MACRO_NR_ARGS(__VA_ARGS__) <= 2); \ |
| PASTE(__run_as_rkm_, MACRO_NR_ARGS(__VA_ARGS__))(f, ##__VA_ARGS__); \ |
| } while (0) |
| |
| #define __run_as_rkm_0(f) \ |
| send_kernel_message(core_id(), __kmsg_trampoline, (long)f, 0xcafebabe, \ |
| 0xcafebabe, KMSG_ROUTINE) |
| #define __run_as_rkm_1(f, a1) \ |
| send_kernel_message(core_id(), __kmsg_trampoline, (long)f, (long)a1, \ |
| 0xcafebabe, KMSG_ROUTINE) |
| #define __run_as_rkm_2(f, a1, a2) \ |
| send_kernel_message(core_id(), __kmsg_trampoline, (long)f, (long)a1, \ |
| (long)a2, KMSG_ROUTINE) |
| void __kmsg_trampoline(uint32_t srcid, long a0, long a1, long a2); |
| |
| /* Kernel context depths. IRQ depth is how many nested IRQ stacks/contexts we |
| * are working on. Kernel trap depth is how many nested kernel traps (not |
| * user-space traps) we have. |
| * |
| * Some examples: |
| * (original context in parens, +(x, y) is the change to IRQ and ktrap |
| * depth): |
| * - syscall (user): +(0, 0) |
| * - trap (user): +(0, 0) |
| * - irq (user): +(1, 0) |
| * - irq (kernel, handling syscall): +(1, 0) |
| * - trap (kernel, regardless of context): +(0, 1) |
| * - NMI (kernel): it's actually a kernel trap, even though it is |
| * sent by IPI. +(0, 1) |
| * - NMI (user): just a trap. +(0, 0) |
| * |
| * So if the user traps in for a syscall (0, 0), then the kernel takes an IRQ |
| * (1, 0), and then another IRQ (2, 0), and then the kernel page faults (a |
| * trap), we're at (2, 1). |
| * |
| * Or if we're in userspace, then an IRQ arrives, we're in the kernel at (1, 0). |
| * Note that regardless of whether or not we are in userspace or the kernel when |
| * an irq arrives, we still are only at level 1 irq depth. We don't care if we |
| * have one or 0 kernel contexts under us. (The reason for this is that I care |
| * if it is *possible* for us to interrupt the kernel, not whether or not it |
| * actually happened). */ |
| |
| /* uint32_t __ctx_depth is laid out like so: |
| * |
| * +------8------+------8------+------8------+------8------+ |
| * | Flags | Unused | Kernel Trap | IRQ Depth | |
| * | | | Depth | | |
| * +-------------+-------------+-------------+-------------+ |
| * |
| */ |
| #define __CTX_IRQ_D_SHIFT 0 |
| #define __CTX_KTRAP_D_SHIFT 8 |
| #define __CTX_FLAG_SHIFT 24 |
| #define __CTX_IRQ_D_MASK ((1 << 8) - 1) |
| #define __CTX_KTRAP_D_MASK ((1 << 8) - 1) |
| #define __CTX_NESTED_CTX_MASK ((1 << 16) - 1) |
| #define __CTX_CANNOT_BLOCK (1 << (__CTX_FLAG_SHIFT + 0)) |
| |
| /* Basic functions to get or change depths */ |
| |
| #define irq_depth(pcpui) \ |
| (((pcpui)->__ctx_depth >> __CTX_IRQ_D_SHIFT) & __CTX_IRQ_D_MASK) |
| |
| #define ktrap_depth(pcpui) \ |
| (((pcpui)->__ctx_depth >> __CTX_KTRAP_D_SHIFT) & __CTX_KTRAP_D_MASK) |
| |
| #define inc_irq_depth(pcpui) \ |
| ((pcpui)->__ctx_depth += 1 << __CTX_IRQ_D_SHIFT) |
| |
| #define dec_irq_depth(pcpui) \ |
| ((pcpui)->__ctx_depth -= 1 << __CTX_IRQ_D_SHIFT) |
| |
| #define inc_ktrap_depth(pcpui) \ |
| ((pcpui)->__ctx_depth += 1 << __CTX_KTRAP_D_SHIFT) |
| |
| #define dec_ktrap_depth(pcpui) \ |
| ((pcpui)->__ctx_depth -= 1 << __CTX_KTRAP_D_SHIFT) |
| |
| #define set_cannot_block(pcpui) \ |
| ((pcpui)->__ctx_depth |= __CTX_CANNOT_BLOCK) |
| |
| #define clear_cannot_block(pcpui) \ |
| ((pcpui)->__ctx_depth &= ~__CTX_CANNOT_BLOCK) |
| |
| /* Functions to query the kernel context depth/state. I haven't fully decided |
| * on whether or not 'default' context includes RKMs or not. Will depend on |
| * how we use it. Check the code below to see what the latest is. */ |
| |
| #define in_irq_ctx(pcpui) \ |
| (irq_depth(pcpui)) |
| |
| /* Right now, anything (KTRAP, IRQ, or RKM) makes us not 'default' */ |
| #define in_default_ctx(pcpui) \ |
| (!(pcpui)->__ctx_depth) |
| |
| /* Can block only if we have no nested contexts (ktraps or irqs, (which are |
| * potentially nested contexts)) and not in an explicit CANNOT_BLOCK. */ |
| #define can_block(pcpui) \ |
| (!((pcpui)->__ctx_depth & (__CTX_NESTED_CTX_MASK | __CTX_CANNOT_BLOCK))) |
| |
| /* TRUE if we are allowed to spin, given that the 'lock' was declared as not |
| * grabbable from IRQ context. Meaning, we can't grab the lock from any nested |
| * context. (And for most locks, we can never grab them from a kernel trap |
| * handler). |
| * |
| * Example is a lock that is not declared as irqsave, but we later grab it from |
| * irq context. This could deadlock the system, even if it doesn't do it this |
| * time. This function will catch that. */ |
| #define can_spinwait_noirq(pcpui) \ |
| (!((pcpui)->__ctx_depth & __CTX_NESTED_CTX_MASK)) |
| |
| /* TRUE if we are allowed to spin, given that the 'lock' was declared as |
| * potentially grabbable by IRQ context (such as with an irqsave lock). We can |
| * never grab from a ktrap, since there is no way to prevent that. And we must |
| * have IRQs disabled, since an IRQ handler could attempt to grab the lock. */ |
| #define can_spinwait_irq(pcpui) \ |
| ((!ktrap_depth(pcpui) && !irq_is_enabled())) |
| |
| /* Debugging */ |
| void print_kctx_depths(const char *str); |
