arch/tile: Miscellaneous cleanup changes.

This commit is primarily changes caused by reviewing "sparse"
and "checkpatch" output on our sources, so is somewhat noisy, since
things like "printk() -> pr_err()" (or whatever) throughout the
codebase tend to get tedious to read.  Rather than trying to tease
apart precisely which things changed due to which type of code
review, this commit includes various cleanups in the code:

- sparse: Add declarations in headers for globals.
- sparse: Fix __user annotations.
- sparse: Using gfp_t consistently instead of int.
- sparse: removing functions not actually used.
- checkpatch: Clean up printk() warnings by using pr_info(), etc.;
  also avoid partial-line printks except in bootup code.
  - checkpatch: Use exposed structs rather than typedefs.
  - checkpatch: Change some C99 comments to C89 comments.

In addition, a couple of minor other changes are rolled in
to this commit:

- Add support for a "raise" instruction to cause SIGFPE, etc., to be raised.
- Remove some compat code that is unnecessary when we fully eliminate
  some of the deprecated syscalls from the generic syscall ABI.
- Update the tile_defconfig to reflect current config contents.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 67 insertions, 43 deletions

diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c
index c70ff14a48e4..ed590ad0acdc 100644
--- a/arch/tile/kernel/process.c
+++ b/arch/tile/kernel/process.c
@@ -24,9 +24,14 @@
 #include <linux/compat.h>
 #include <linux/hardirq.h>
 #include <linux/syscalls.h>
+#include <linux/kernel.h>
 #include <asm/system.h>
 #include <asm/stack.h>
 #include <asm/homecache.h>
+#include <asm/syscalls.h>
+#ifdef CONFIG_HARDWALL
+#include <asm/hardwall.h>
+#endif
 #include <arch/chip.h>
 #include <arch/abi.h>
 
@@ -43,7 +48,7 @@ static int __init idle_setup(char *str)
 		return -EINVAL;
 
 	if (!strcmp(str, "poll")) {
-		printk("using polling idle threads.\n");
+		pr_info("using polling idle threads.\n");
 		no_idle_nap = 1;
 	} else if (!strcmp(str, "halt"))
 		no_idle_nap = 0;
@@ -62,7 +67,6 @@ early_param("idle", idle_setup);
  */
 void cpu_idle(void)
 {
-	extern void _cpu_idle(void);
 	int cpu = smp_processor_id();
 
 
@@ -108,7 +112,7 @@ void cpu_idle(void)
 struct thread_info *alloc_thread_info(struct task_struct *task)
 {
 	struct page *page;
-	int flags = GFP_KERNEL;
+	gfp_t flags = GFP_KERNEL;
 
 #ifdef CONFIG_DEBUG_STACK_USAGE
 	flags |= __GFP_ZERO;
@@ -116,7 +120,7 @@ struct thread_info *alloc_thread_info(struct task_struct *task)
 
 	page = alloc_pages(flags, THREAD_SIZE_ORDER);
 	if (!page)
-		return 0;
+		return NULL;
 
 	return (struct thread_info *)page_address(page);
 }
@@ -129,6 +133,18 @@ void free_thread_info(struct thread_info *info)
 {
 	struct single_step_state *step_state = info->step_state;
 
+#ifdef CONFIG_HARDWALL
+	/*
+	 * We free a thread_info from the context of the task that has
+	 * been scheduled next, so the original task is already dead.
+	 * Calling deactivate here just frees up the data structures.
+	 * If the task we're freeing held the last reference to a
+	 * hardwall fd, it would have been released prior to this point
+	 * anyway via exit_files(), and "hardwall" would be NULL by now.
+	 */
+	if (info->task->thread.hardwall)
+		hardwall_deactivate(info->task);
+#endif
 
 	if (step_state) {
 
@@ -154,8 +170,6 @@ void free_thread_info(struct thread_info *info)
 
 static void save_arch_state(struct thread_struct *t);
 
-extern void ret_from_fork(void);
-
 int copy_thread(unsigned long clone_flags, unsigned long sp,
 		unsigned long stack_size,
 		struct task_struct *p, struct pt_regs *regs)
@@ -235,6 +249,10 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 	p->thread.proc_status = 0;
 #endif
 
+#ifdef CONFIG_HARDWALL
+	/* New thread does not own any networks. */
+	p->thread.hardwall = NULL;
+#endif
 
 
 	/*
@@ -257,7 +275,7 @@ struct task_struct *validate_current(void)
 	if (unlikely((unsigned long)tsk < PAGE_OFFSET ||
 		     (void *)tsk > high_memory ||
 		     ((unsigned long)tsk & (__alignof__(*tsk) - 1)) != 0)) {
-		printk("Corrupt 'current' %p (sp %#lx)\n", tsk, stack_pointer);
+		pr_err("Corrupt 'current' %p (sp %#lx)\n", tsk, stack_pointer);
 		tsk = &corrupt;
 	}
 	return tsk;
@@ -447,10 +465,6 @@ void _prepare_arch_switch(struct task_struct *next)
 }
 
 
-extern struct task_struct *__switch_to(struct task_struct *prev,
-				       struct task_struct *next,
-				       unsigned long new_system_save_1_0);
-
 struct task_struct *__sched _switch_to(struct task_struct *prev,
 				       struct task_struct *next)
 {
@@ -486,6 +500,15 @@ struct task_struct *__sched _switch_to(struct task_struct *prev,
 	}
 #endif
 
+#ifdef CONFIG_HARDWALL
+	/* Enable or disable access to the network registers appropriately. */
+	if (prev->thread.hardwall != NULL) {
+		if (next->thread.hardwall == NULL)
+			restrict_network_mpls();
+	} else if (next->thread.hardwall != NULL) {
+		grant_network_mpls();
+	}
+#endif
 
 	/*
 	 * Switch kernel SP, PC, and callee-saved registers.
@@ -496,14 +519,14 @@ struct task_struct *__sched _switch_to(struct task_struct *prev,
 	return __switch_to(prev, next, next_current_ksp0(next));
 }
 
-int _sys_fork(struct pt_regs *regs)
+long _sys_fork(struct pt_regs *regs)
 {
 	return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
 }
 
-int _sys_clone(unsigned long clone_flags, unsigned long newsp,
-	       void __user *parent_tidptr, void __user *child_tidptr,
-	       struct pt_regs *regs)
+long _sys_clone(unsigned long clone_flags, unsigned long newsp,
+		void __user *parent_tidptr, void __user *child_tidptr,
+		struct pt_regs *regs)
 {
 	if (!newsp)
 		newsp = regs->sp;
@@ -511,7 +534,7 @@ int _sys_clone(unsigned long clone_flags, unsigned long newsp,
 		       parent_tidptr, child_tidptr);
 }
 
-int _sys_vfork(struct pt_regs *regs)
+long _sys_vfork(struct pt_regs *regs)
 {
 	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp,
 		       regs, 0, NULL, NULL);
@@ -520,10 +543,10 @@ int _sys_vfork(struct pt_regs *regs)
 /*
  * sys_execve() executes a new program.
  */
-int _sys_execve(char __user *path, char __user *__user *argv,
-		char __user *__user *envp, struct pt_regs *regs)
+long _sys_execve(char __user *path, char __user *__user *argv,
+		 char __user *__user *envp, struct pt_regs *regs)
 {
-	int error;
+	long error;
 	char *filename;
 
 	filename = getname(path);
@@ -537,10 +560,10 @@ out:
 }
 
 #ifdef CONFIG_COMPAT
-int _compat_sys_execve(char __user *path, compat_uptr_t __user *argv,
-		       compat_uptr_t __user *envp, struct pt_regs *regs)
+long _compat_sys_execve(char __user *path, compat_uptr_t __user *argv,
+			compat_uptr_t __user *envp, struct pt_regs *regs)
 {
-	int error;
+	long error;
 	char *filename;
 
 	filename = getname(path);
@@ -616,31 +639,32 @@ void exit_thread(void)
 	/* Nothing */
 }
 
-#ifdef __tilegx__
-# define LINECOUNT 3
-# define EXTRA_NL "\n"
-#else
-# define LINECOUNT 4
-# define EXTRA_NL ""
-#endif
-
 void show_regs(struct pt_regs *regs)
 {
 	struct task_struct *tsk = validate_current();
-	int i, linebreak;
-	printk("\n");
-	printk(" Pid: %d, comm: %20s, CPU: %d\n",
+	int i;
+
+	pr_err("\n");
+	pr_err(" Pid: %d, comm: %20s, CPU: %d\n",
 	       tsk->pid, tsk->comm, smp_processor_id());
-	for (i = linebreak = 0; i < 53; ++i) {
-		printk(" r%-2d: "REGFMT, i, regs->regs[i]);
-		if (++linebreak == LINECOUNT) {
-			linebreak = 0;
-			printk("\n");
-		}
-	}
-	printk(" tp : "REGFMT EXTRA_NL " sp : "REGFMT" lr : "REGFMT"\n",
-	       regs->tp, regs->sp, regs->lr);
-	printk(" pc : "REGFMT" ex1: %ld     faultnum: %ld\n",
+#ifdef __tilegx__
+	for (i = 0; i < 51; i += 3)
+		pr_err(" r%-2d: "REGFMT" r%-2d: "REGFMT" r%-2d: "REGFMT"\n",
+		       i, regs->regs[i], i+1, regs->regs[i+1],
+		       i+2, regs->regs[i+2]);
+	pr_err(" r51: "REGFMT" r52: "REGFMT" tp : "REGFMT"\n",
+	       regs->regs[51], regs->regs[52], regs->tp);
+	pr_err(" sp : "REGFMT" lr : "REGFMT"\n", regs->sp, regs->lr);
+#else
+	for (i = 0; i < 52; i += 3)
+		pr_err(" r%-2d: "REGFMT" r%-2d: "REGFMT
+		       " r%-2d: "REGFMT" r%-2d: "REGFMT"\n",
+		       i, regs->regs[i], i+1, regs->regs[i+1],
+		       i+2, regs->regs[i+2], i+3, regs->regs[i+3]);
+	pr_err(" r52: "REGFMT" tp : "REGFMT" sp : "REGFMT" lr : "REGFMT"\n",
+	       regs->regs[52], regs->tp, regs->sp, regs->lr);
+#endif
+	pr_err(" pc : "REGFMT" ex1: %ld     faultnum: %ld\n",
 	       regs->pc, regs->ex1, regs->faultnum);
 
 	dump_stack_regs(regs);