Merge tag 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml

Pull UML updates from Richard Weinberger:
 - hostfs saw a face lifting
 - old/broken stuff was removed (SMP, HIGHMEM, SKAS3/4)
 - random cleanups and bug fixes

* tag 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (26 commits)
  um: Print minimum physical memory requirement
  um: Move uml_postsetup in the init_thread stack
  um: add a kmsg_dumper
  x86, UML: fix integer overflow in ELF_ET_DYN_BASE
  um: hostfs: Reduce number of syscalls in readdir
  um: Remove broken highmem support
  um: Remove broken SMP support
  um: Remove SKAS3/4 support
  um: Remove ppc cruft
  um: Remove ia64 cruft
  um: Remove dead code from stacktrace
  hostfs: No need to box and later unbox the file mode
  hostfs: Use page_offset()
  hostfs: Set page flags in hostfs_readpage() correctly
  hostfs: Remove superfluous initializations in hostfs_open()
  hostfs: hostfs_open: Reset open flags upon each retry
  hostfs: Remove superfluous test in hostfs_open()
  hostfs: Report append flag in ->show_options()
  hostfs: Use __getname() in follow_link
  hostfs: Remove open coded strcpy()
  ...

arch/um/Kconfig.um

@@ -95,48 +95,6 @@ config MAGIC_SYSRQ
 	  The keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
 	  unless you really know what this hack does.
 
-config SMP
-	bool "Symmetric multi-processing support"
-	default n
-	depends on BROKEN
-	help
-	  This option enables UML SMP support.
-	  It is NOT related to having a real SMP box. Not directly, at least.
-
-	  UML implements virtual SMP by allowing as many processes to run
-	  simultaneously on the host as there are virtual processors configured.
-
-	  Obviously, if the host is a uniprocessor, those processes will
-	  timeshare, but, inside UML, will appear to be running simultaneously.
-	  If the host is a multiprocessor, then UML processes may run
-	  simultaneously, depending on the host scheduler.
-
-	  This, however, is supported only in TT mode. So, if you use the SKAS
-	  patch on your host, switching to TT mode and enabling SMP usually
-	  gives	you worse performances.
-	  Also, since the support for SMP has been under-developed, there could
-	  be some bugs being exposed by enabling SMP.
-
-	  If you don't know what to do, say N.
-
-config NR_CPUS
-	int "Maximum number of CPUs (2-32)"
-	range 2 32
-	depends on SMP
-	default "32"
-
-config HIGHMEM
-	bool "Highmem support"
-	depends on !64BIT && BROKEN
-	default n
-	help
-	  This was used to allow UML to run with big amounts of memory.
-	  Currently it is unstable, so if unsure say N.
-
-	  To use big amounts of memory, it is recommended enable static
-	  linking (i.e. CONFIG_STATIC_LINK) - this should allow the
-	  guest to use up to 2.75G of memory.
-
 config KERNEL_STACK_ORDER
 	int "Kernel stack size order"
 	default 1 if 64BIT

arch/um/Makefile-ia64

@@ -1 +0,0 @@
-START_ADDR = 0x1000000000000000

arch/um/Makefile-ppc

@@ -1,9 +0,0 @@
-ifeq ($(CONFIG_HOST_2G_2G), y)
-START_ADDR = 0x80000000
-else
-START_ADDR = 0xc0000000
-endif
-ARCH_CFLAGS = -U__powerpc__ -D__UM_PPC__
-
-# The arch is ppc, but the elf32 name is powerpc
-ELF_SUBARCH = powerpc

arch/um/include/asm/fixmap.h

@@ -33,10 +33,6 @@
  * fix-mapped?
  */
 enum fixed_addresses {
-#ifdef CONFIG_HIGHMEM
-	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
-	FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
-#endif
 	__end_of_fixed_addresses
 };
 

arch/um/include/asm/pgtable.h

@@ -47,11 +47,7 @@ extern unsigned long end_iomem;
 #define VMALLOC_OFFSET	(__va_space)
 #define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
 #define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
-#ifdef CONFIG_HIGHMEM
-# define VMALLOC_END	(PKMAP_BASE-2*PAGE_SIZE)
-#else
-# define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
-#endif
+#define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
 #define MODULES_VADDR	VMALLOC_START
 #define MODULES_END	VMALLOC_END
 #define MODULES_LEN	(MODULES_VADDR - MODULES_END)

arch/um/include/asm/processor-generic.h

@@ -98,16 +98,8 @@ struct cpuinfo_um {
 
 extern struct cpuinfo_um boot_cpu_data;
 
-#define my_cpu_data		cpu_data[smp_processor_id()]
-
-#ifdef CONFIG_SMP
-extern struct cpuinfo_um cpu_data[];
-#define current_cpu_data cpu_data[smp_processor_id()]
-#else
 #define cpu_data (&boot_cpu_data)
 #define current_cpu_data boot_cpu_data
-#endif
-
 
 #define KSTK_REG(tsk, reg) get_thread_reg(reg, &tsk->thread.switch_buf)
 extern unsigned long get_wchan(struct task_struct *p);

arch/um/include/asm/smp.h

@@ -1,32 +1,6 @@
 #ifndef __UM_SMP_H
 #define __UM_SMP_H
 
-#ifdef CONFIG_SMP
-
-#include <linux/bitops.h>
-#include <asm/current.h>
-#include <linux/cpumask.h>
-
-#define raw_smp_processor_id() (current_thread->cpu)
-
-#define cpu_logical_map(n) (n)
-#define cpu_number_map(n) (n)
-extern int hard_smp_processor_id(void);
-#define NO_PROC_ID -1
-
-extern int ncpus;
-
-
-static inline void smp_cpus_done(unsigned int maxcpus)
-{
-}
-
-extern struct task_struct *idle_threads[NR_CPUS];
-
-#else
-
 #define hard_smp_processor_id()		0
 
 #endif
-
-#endif

arch/um/include/shared/as-layout.h

@@ -56,6 +56,7 @@ extern unsigned long brk_start;
 extern unsigned long host_task_size;
 
 extern int linux_main(int argc, char **argv);
+extern void uml_finishsetup(void);
 
 struct siginfo;
 extern void (*sig_info[])(int, struct siginfo *si, struct uml_pt_regs *);

arch/um/include/shared/os.h

@@ -174,7 +174,6 @@ extern unsigned long long os_makedev(unsigned major, unsigned minor);
 
 /* start_up.c */
 extern void os_early_checks(void);
-extern void can_do_skas(void);
 extern void os_check_bugs(void);
 extern void check_host_supports_tls(int *supports_tls, int *tls_min);
 
@@ -187,7 +186,6 @@ extern int os_process_parent(int pid);
 extern void os_stop_process(int pid);
 extern void os_kill_process(int pid, int reap_child);
 extern void os_kill_ptraced_process(int pid, int reap_child);
-extern long os_ptrace_ldt(long pid, long addr, long data);
 
 extern int os_getpid(void);
 extern int os_getpgrp(void);

arch/um/include/shared/skas/proc_mm.h

@@ -1,44 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#ifndef __SKAS_PROC_MM_H
-#define __SKAS_PROC_MM_H
-
-#define MM_MMAP 54
-#define MM_MUNMAP 55
-#define MM_MPROTECT 56
-#define MM_COPY_SEGMENTS 57
-
-struct mm_mmap {
-	unsigned long addr;
-	unsigned long len;
-	unsigned long prot;
-	unsigned long flags;
-	unsigned long fd;
-	unsigned long offset;
-};
-
-struct mm_munmap {
-	unsigned long addr;
-	unsigned long len;
-};
-
-struct mm_mprotect {
-	unsigned long addr;
-	unsigned long len;
-	unsigned int prot;
-};
-
-struct proc_mm_op {
-	int op;
-	union {
-		struct mm_mmap mmap;
-		struct mm_munmap munmap;
-	        struct mm_mprotect mprotect;
-		int copy_segments;
-	} u;
-};
-
-#endif

arch/um/include/shared/skas/skas.h

@@ -9,13 +9,10 @@
 #include <sysdep/ptrace.h>
 
 extern int userspace_pid[];
-extern int proc_mm, ptrace_faultinfo, ptrace_ldt;
-extern int skas_needs_stub;
 
 extern int user_thread(unsigned long stack, int flags);
 extern void new_thread_handler(void);
 extern void handle_syscall(struct uml_pt_regs *regs);
-extern int new_mm(unsigned long stack);
 extern long execute_syscall_skas(void *r);
 extern unsigned long current_stub_stack(void);
 

arch/um/include/shared/skas_ptrace.h

@@ -1,14 +0,0 @@
-/* 
- * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
- */
-
-#ifndef __SKAS_PTRACE_H
-#define __SKAS_PTRACE_H
-
-#define PTRACE_FAULTINFO 52
-#define PTRACE_SWITCH_MM 55
-
-#include <sysdep/skas_ptrace.h>
-
-#endif

arch/um/kernel/Makefile

@@ -12,8 +12,8 @@ clean-files :=
 
 obj-y = config.o exec.o exitcode.o irq.o ksyms.o mem.o \
 	physmem.o process.o ptrace.o reboot.o sigio.o \
-	signal.o smp.o syscall.o sysrq.o time.o tlb.o trap.o \
-	um_arch.o umid.o maccess.o skas/
+	signal.o syscall.o sysrq.o time.o tlb.o trap.o \
+	um_arch.o umid.o maccess.o kmsg_dump.o skas/
 
 obj-$(CONFIG_BLK_DEV_INITRD) += initrd.o
 obj-$(CONFIG_GPROF)	+= gprof_syms.o

arch/um/kernel/irq.c

@@ -35,9 +35,6 @@ void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
 	struct irq_fd *irq_fd;
 	int n;
 
-	if (smp_sigio_handler())
-		return;
-
 	while (1) {
 		n = os_waiting_for_events(active_fds);
 		if (n <= 0) {

arch/um/kernel/kmsg_dump.c

@@ -0,0 +1,43 @@
+#include <linux/kmsg_dump.h>
+#include <linux/console.h>
+#include <shared/init.h>
+#include <shared/kern.h>
+#include <os.h>
+
+static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
+				enum kmsg_dump_reason reason)
+{
+	static char line[1024];
+
+	size_t len = 0;
+	bool con_available = false;
+
+	/* only dump kmsg when no console is available */
+	if (!console_trylock())
+		return;
+
+	if (console_drivers != NULL)
+		con_available = true;
+
+	console_unlock();
+
+	if (con_available == true)
+		return;
+
+	printf("kmsg_dump:\n");
+	while (kmsg_dump_get_line(dumper, true, line, sizeof(line), &len)) {
+		line[len] = '\0';
+		printf("%s", line);
+	}
+}
+
+static struct kmsg_dumper kmsg_dumper = {
+	.dump = kmsg_dumper_stdout
+};
+
+int __init kmsg_dumper_stdout_init(void)
+{
+	return kmsg_dump_register(&kmsg_dumper);
+}
+
+__uml_postsetup(kmsg_dumper_stdout_init);

arch/um/kernel/mem.c

@@ -38,19 +38,6 @@ int kmalloc_ok = 0;
 /* Used during early boot */
 static unsigned long brk_end;
 
-#ifdef CONFIG_HIGHMEM
-static void setup_highmem(unsigned long highmem_start,
-			  unsigned long highmem_len)
-{
-	unsigned long highmem_pfn;
-	int i;
-
-	highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
-	for (i = 0; i < highmem_len >> PAGE_SHIFT; i++)
-		free_highmem_page(&mem_map[highmem_pfn + i]);
-}
-#endif
-
 void __init mem_init(void)
 {
 	/* clear the zero-page */
@@ -67,9 +54,6 @@ void __init mem_init(void)
 	/* this will put all low memory onto the freelists */
 	free_all_bootmem();
 	max_low_pfn = totalram_pages;
-#ifdef CONFIG_HIGHMEM
-	setup_highmem(end_iomem, highmem);
-#endif
 	max_pfn = totalram_pages;
 	mem_init_print_info(NULL);
 	kmalloc_ok = 1;
@@ -127,49 +111,6 @@ static void __init fixrange_init(unsigned long start, unsigned long end,
 	}
 }
 
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-pgprot_t kmap_prot;
-
-#define kmap_get_fixmap_pte(vaddr)					\
-	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)),\
-				     (vaddr)), (vaddr))
-
-static void __init kmap_init(void)
-{
-	unsigned long kmap_vstart;
-
-	/* cache the first kmap pte */
-	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
-
-	kmap_prot = PAGE_KERNEL;
-}
-
-static void __init init_highmem(void)
-{
-	pgd_t *pgd;
-	pud_t *pud;
-	pmd_t *pmd;
-	pte_t *pte;
-	unsigned long vaddr;
-
-	/*
-	 * Permanent kmaps:
-	 */
-	vaddr = PKMAP_BASE;
-	fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
-
-	pgd = swapper_pg_dir + pgd_index(vaddr);
-	pud = pud_offset(pgd, vaddr);
-	pmd = pmd_offset(pud, vaddr);
-	pte = pte_offset_kernel(pmd, vaddr);
-	pkmap_page_table = pte;
-
-	kmap_init();
-}
-#endif /* CONFIG_HIGHMEM */
-
 static void __init fixaddr_user_init( void)
 {
 #ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
@@ -211,9 +152,6 @@ void __init paging_init(void)
 
 	zones_size[ZONE_NORMAL] = (end_iomem >> PAGE_SHIFT) -
 		(uml_physmem >> PAGE_SHIFT);
-#ifdef CONFIG_HIGHMEM
-	zones_size[ZONE_HIGHMEM] = highmem >> PAGE_SHIFT;
-#endif
 	free_area_init(zones_size);
 
 	/*
@@ -224,10 +162,6 @@ void __init paging_init(void)
 	fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
 
 	fixaddr_user_init();
-
-#ifdef CONFIG_HIGHMEM
-	init_highmem();
-#endif
 }
 
 /*

arch/um/kernel/physmem.c

@@ -57,22 +57,51 @@ void map_memory(unsigned long virt, unsigned long phys, unsigned long len,
 
 extern int __syscall_stub_start;
 
+/**
+ * setup_physmem() - Setup physical memory for UML
+ * @start:	Start address of the physical kernel memory,
+ *		i.e start address of the executable image.
+ * @reserve_end:	end address of the physical kernel memory.
+ * @len:	Length of total physical memory that should be mapped/made
+ *		available, in bytes.
+ * @highmem:	Number of highmem bytes that should be mapped/made available.
+ *
+ * Creates an unlinked temporary file of size (len + highmem) and memory maps
+ * it on the last executable image address (uml_reserved).
+ *
+ * The offset is needed as the length of the total physical memory
+ * (len + highmem) includes the size of the memory used be the executable image,
+ * but the mapped-to address is the last address of the executable image
+ * (uml_reserved == end address of executable image).
+ *
+ * The memory mapped memory of the temporary file is used as backing memory
+ * of all user space processes/kernel tasks.
+ */
 void __init setup_physmem(unsigned long start, unsigned long reserve_end,
 			  unsigned long len, unsigned long long highmem)
 {
 	unsigned long reserve = reserve_end - start;
-	int pfn = PFN_UP(__pa(reserve_end));
-	int delta = (len - reserve) >> PAGE_SHIFT;
-	int err, offset, bootmap_size;
+	unsigned long pfn = PFN_UP(__pa(reserve_end));
+	unsigned long delta = (len - reserve) >> PAGE_SHIFT;
+	unsigned long offset, bootmap_size;
+	long map_size;
+	int err;
+
+	offset = uml_reserved - uml_physmem;
+	map_size = len - offset;
+	if(map_size <= 0) {
+		printf("Too few physical memory! Needed=%d, given=%d\n",
+		       offset, len);
+		exit(1);
+	}
 
 	physmem_fd = create_mem_file(len + highmem);
 
-	offset = uml_reserved - uml_physmem;
 	err = os_map_memory((void *) uml_reserved, physmem_fd, offset,
-			    len - offset, 1, 1, 1);
+			    map_size, 1, 1, 1);
 	if (err < 0) {
 		printf("setup_physmem - mapping %ld bytes of memory at 0x%p "
-		       "failed - errno = %d\n", len - offset,
+		       "failed - errno = %d\n", map_size,
 		       (void *) uml_reserved, err);
 		exit(1);
 	}

arch/um/kernel/process.c

@@ -259,17 +259,6 @@ int strlen_user_proc(char __user *str)
 	return strlen_user(str);
 }
 
-int smp_sigio_handler(void)
-{
-#ifdef CONFIG_SMP
-	int cpu = current_thread_info()->cpu;
-	IPI_handler(cpu);
-	if (cpu != 0)
-		return 1;
-#endif
-	return 0;
-}
-
 int cpu(void)
 {
 	return current_thread_info()->cpu;

arch/um/kernel/ptrace.c

@@ -8,9 +8,6 @@
 #include <linux/sched.h>
 #include <linux/tracehook.h>
 #include <asm/uaccess.h>
-#include <skas_ptrace.h>
-
-
 
 void user_enable_single_step(struct task_struct *child)
 {
@@ -104,35 +101,6 @@ long arch_ptrace(struct task_struct *child, long request,
 		ret = ptrace_set_thread_area(child, addr, vp);
 		break;
 
-	case PTRACE_FAULTINFO: {
-		/*
-		 * Take the info from thread->arch->faultinfo,
-		 * but transfer max. sizeof(struct ptrace_faultinfo).
-		 * On i386, ptrace_faultinfo is smaller!
-		 */
-		ret = copy_to_user(p, &child->thread.arch.faultinfo,
-				   sizeof(struct ptrace_faultinfo)) ?
-			-EIO : 0;
-		break;
-	}
-
-#ifdef PTRACE_LDT
-	case PTRACE_LDT: {
-		struct ptrace_ldt ldt;
-
-		if (copy_from_user(&ldt, p, sizeof(ldt))) {
-			ret = -EIO;
-			break;
-		}
-
-		/*
-		 * This one is confusing, so just punt and return -EIO for
-		 * now
-		 */
-		ret = -EIO;
-		break;
-	}
-#endif
 	default:
 		ret = ptrace_request(child, request, addr, data);
 		if (ret == -EIO)

arch/um/kernel/reboot.c

@@ -15,28 +15,21 @@ void (*pm_power_off)(void);
 
 static void kill_off_processes(void)
 {
-	if (proc_mm)
-		/*
-		 * FIXME: need to loop over userspace_pids
-		 */
-		os_kill_ptraced_process(userspace_pid[0], 1);
-	else {
-		struct task_struct *p;
-		int pid;
+	struct task_struct *p;
+	int pid;
 
-		read_lock(&tasklist_lock);
-		for_each_process(p) {
-			struct task_struct *t;
+	read_lock(&tasklist_lock);
+	for_each_process(p) {
+		struct task_struct *t;
 
-			t = find_lock_task_mm(p);
-			if (!t)
-				continue;
-			pid = t->mm->context.id.u.pid;
-			task_unlock(t);
-			os_kill_ptraced_process(pid, 1);
-		}
-		read_unlock(&tasklist_lock);
+		t = find_lock_task_mm(p);
+		if (!t)
+			continue;
+		pid = t->mm->context.id.u.pid;
+		task_unlock(t);
+		os_kill_ptraced_process(pid, 1);
 	}
+	read_unlock(&tasklist_lock);
 }
 
 void uml_cleanup(void)