kernel: don't use pointer types for registers, add proc_savereturn

8 files changed, 26 insertions, 27 deletions

diff --git a/src/kernel/arch/amd64/registers.h b/src/kernel/arch/amd64/registers.h
index cfbfa54..a76062f 100644
--- a/src/kernel/arch/amd64/registers.h
+++ b/src/kernel/arch/amd64/registers.h
@@ -5,14 +5,7 @@
 /* requires 16-byte alignment */
 struct CpuRegs {
 	uint64_t r15, r14, r13, r12, r11, r10, r9, r8;
-	uint64_t rdi, rsi;
-	userptr_t rbp, rsp;
-	uint64_t rbx, rdx, rcx, rax, rip, flags;
+	uint64_t rdi, rsi, rbp, rsp, rbx, rdx, rcx, rax;
+	uint64_t rip, flags;
 	uint8_t _sse[512];
 } __attribute__((__packed__));
-
-// saves a return value according to the SysV ABI
-static inline uint64_t regs_savereturn(CpuRegs *regs, uint64_t value) {
-	regs->rax = value;
-	return value;
-}
diff --git a/src/kernel/pipe.c b/src/kernel/pipe.c
index b7f5ad3..5efafc8 100644
--- a/src/kernel/pipe.c
+++ b/src/kernel/pipe.c
@@ -9,7 +9,7 @@ void pipe_joinqueue(Handle *h, Proc *proc, void __user *pbuf, size_t pbuflen) {
 	assert(h && h->type == HANDLE_PIPE);
 	assert(h->readable ^ h->writeable);
 	if (!h->pipe.sister) {
-		regs_savereturn(&proc->regs, h->readable ? 0 : -EPIPE);
+		proc_savereturn(proc, h->readable ? 0 : -EPIPE);
 		return;
 	}
 
@@ -54,8 +54,8 @@ static void pipe_trytransfer(Handle *h) {
 	h->pipe.sister->pipe.queued = h->pipe.sister->pipe.queued->waits4pipe.next;
 	proc_setstate(rdr, PS_RUNNING);
 	proc_setstate(wtr, PS_RUNNING);
-	regs_savereturn(&rdr->regs, len);
-	regs_savereturn(&wtr->regs, len);
+	proc_savereturn(rdr, len);
+	proc_savereturn(wtr, len);
 }
 
 void pipe_invalidate_end(Handle *h) {
@@ -63,7 +63,7 @@ void pipe_invalidate_end(Handle *h) {
 	while (p) {
 		assert(p->state == PS_WAITS4PIPE);
 		proc_setstate(p, PS_RUNNING);
-		regs_savereturn(&p->regs, -1);
+		proc_savereturn(p, -1);
 		p = p->waits4pipe.next;
 	}
 	h->pipe.queued = NULL;
diff --git a/src/kernel/proc.c b/src/kernel/proc.c
index 8be1080..d85384f 100644
--- a/src/kernel/proc.c
+++ b/src/kernel/proc.c
@@ -309,7 +309,7 @@ void proc_tryreap(Proc *dead) {
 			if (parent->awaited_death.pid && parent->awaited_death.pid != pid) {
 				return; /* we're not The One */
 			}
-			regs_savereturn(&parent->regs, pid);
+			proc_savereturn(parent, pid);
 			if (parent->awaited_death.out) {
 				struct sys_wait2 __user *out = parent->awaited_death.out;
 				struct sys_wait2 data;
@@ -417,14 +417,14 @@ static void proc_intr_deliver(Proc *p) {
 
 	// one more because the buffer itself isn't NUL terminated
 	// TODO ensure NUL termination
-	void __user *sp = p->regs.rsp - 128 - sizeof(d) - intr->len - 1;
+	void __user *sp = (void __user*)(p->regs.rsp - 128 - sizeof(d) - intr->len - 1);
 	pcpy_to(p, sp, &d, sizeof(d));
 	pcpy_to(p, sp + sizeof(d), intr->buf, intr->len);
 	pcpy_to(p, sp + sizeof(d) + intr->len, "", 1);
 
 	/* switch to intr handler */
 	p->regs.rip = (uint64_t)p->intr_fn;
-	p->regs.rsp = sp;
+	p->regs.rsp = (uint64_t)sp;
 
 	kfree(p->queuedintr);
 	p->queuedintr = NULL;
@@ -518,6 +518,10 @@ Proc *proc_next(Proc *root, Proc *p) {
 	return p->sibling;
 }
 
+void proc_savereturn(Proc *p, uint64_t val) {
+	p->regs.rax = val;
+}
+
 void proc_setstate(Proc *p, enum proc_state state) {
 	assert(p->state != PS_FREED);
 	if (state == PS_FREED) {
diff --git a/src/kernel/proc.h b/src/kernel/proc.h
index 96cd8ba..a371e04 100644
--- a/src/kernel/proc.h
+++ b/src/kernel/proc.h
@@ -131,6 +131,9 @@ _Noreturn void proc_switch_any(void);
 
 Proc *proc_next(Proc *root, Proc *p);
 
+/** Saves a return value. */
+void proc_savereturn(Proc *p, uint64_t val);
+
 void proc_setstate(Proc *, enum proc_state);
 
 size_t pcpy_to(Proc *p, __user void *dst, const void *src, size_t len);
diff --git a/src/kernel/syscalls.c b/src/kernel/syscalls.c
index ffd69b8..42f548e 100644
--- a/src/kernel/syscalls.c
+++ b/src/kernel/syscalls.c
@@ -14,7 +14,7 @@
 
 #define SYSCALL_RETURN(val) do { \
 	assert(proc_cur->state == PS_RUNNING); \
-	regs_savereturn(&proc_cur->regs, (long)(val)); \
+	proc_savereturn(proc_cur, (long)(val)); \
 	return 0; \
 } while (0)
 
@@ -27,7 +27,7 @@ long _sys_fork(int flags, hid_t __user *fs_front) {
 	Proc *child;
 
 	child = proc_fork(proc_cur, flags);
-	regs_savereturn(&child->regs, 0);
+	proc_savereturn(child, 0);
 
 	if (flags & FORK_NEWFS) {
 		Handle *h;
@@ -589,7 +589,7 @@ long _syscall(long num, long a, long b, long c, long d, long e) {
 		break; case _SYS_DEBUG_KLOG:	_sys_debug_klog((userptr_t)a, b);
 		break;
 		default:
-			regs_savereturn(&proc_cur->regs, -1);
+			proc_savereturn(proc_cur, -1);
 			break;
 	}
 	/* return value is unused. execution continues in sysenter_stage2 */
diff --git a/src/kernel/vfs/request.c b/src/kernel/vfs/request.c
index 3f6fda7..69a007e 100644
--- a/src/kernel/vfs/request.c
+++ b/src/kernel/vfs/request.c
@@ -115,7 +115,7 @@ vfsreq_finish(VfsReq *req, char __user *stored, long ret, int flags, Proc *handl
 
 	if (req->caller) {
 		assert(req->caller->state == PS_WAITS4FS);
-		regs_savereturn(&req->caller->regs, ret);
+		proc_savereturn(req->caller, ret);
 		proc_setstate(req->caller, PS_RUNNING);
 	}
 	kfree(req);
@@ -181,7 +181,7 @@ vfsback_useraccept(VfsReq *req)
 	if (hid < 0) panic_unimplemented();
 	h->req = req;
 	proc_setstate(handler, PS_RUNNING);
-	regs_savereturn(&handler->regs, hid);
+	proc_savereturn(handler, hid);
 	req->backend->user.handler = NULL;
 }
 
@@ -210,7 +210,7 @@ vfsback_userdown(VfsBackend *b)
 			Proc *p = b->user.handler;
 			b->user.handler = NULL;
 			assert(p->state == PS_WAITS4REQUEST);
-			regs_savereturn(&p->regs, -EPIPE);
+			proc_savereturn(p, -EPIPE);
 			proc_setstate(p, PS_RUNNING);
 		}
 	}
diff --git a/src/libc/intr.c b/src/libc/intr.c
index c44a90e..12e6f4c 100644
--- a/src/libc/intr.c
+++ b/src/libc/intr.c
@@ -9,6 +9,6 @@ void intr_set(void (*fn)(struct intr_data *)) {
 	_intr = fn ? fn : intr_null;
 }
 
-void intr_default(struct intr_data *intr) {
+void intr_default(struct intr_data *) {
 	exit(-1);
 }
diff --git a/src/libk/include/camellia/types.h b/src/libk/include/camellia/types.h
index 86ffb56..6fee578 100644
--- a/src/libk/include/camellia/types.h
+++ b/src/libk/include/camellia/types.h
@@ -37,10 +37,9 @@ struct intr_data {
 	 * notable omissions:
 	 * - SSE registers (usually there's no need to save them, userland can do
 	 *                  that itself if it wants) */
-	uint64_t r15, r14, r13, r12, r11, r10, r9, r8;
-	uint64_t rdi, rsi;
-	userptr_t rbp, rsp;
-	uint64_t rbx, rdx, rcx, rax, rip, flags;
+	uint64_t r15, r14, r13, r12, r11, r10, r9,  r8;
+	uint64_t rdi, rsi, rbp, rsp, rbx, rdx, rcx, rax;
+	uint64_t rip, flags;
 
 	char msg[]; /* variable size, NUL terminated */
 };