um: merge arch/um/sys-{i386,x86_64}

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 0 insertions, 502 deletions

diff --git a/arch/um/sys-i386/ldt.c b/arch/um/sys-i386/ldt.c
deleted file mode 100644
index 3f2bf208d884..000000000000
--- a/arch/um/sys-i386/ldt.c
+++ /dev/null
@@ -1,502 +0,0 @@
-/*
- * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
- */
-
-#include <linux/mm.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <asm/unistd.h>
-#include "os.h"
-#include "proc_mm.h"
-#include "skas.h"
-#include "skas_ptrace.h"
-#include "sysdep/tls.h"
-
-extern int modify_ldt(int func, void *ptr, unsigned long bytecount);
-
-static long write_ldt_entry(struct mm_id *mm_idp, int func,
-		     struct user_desc *desc, void **addr, int done)
-{
-	long res;
-
-	if (proc_mm) {
-		/*
-		 * This is a special handling for the case, that the mm to
-		 * modify isn't current->active_mm.
-		 * If this is called directly by modify_ldt,
-		 *     (current->active_mm->context.skas.u == mm_idp)
-		 * will be true. So no call to __switch_mm(mm_idp) is done.
-		 * If this is called in case of init_new_ldt or PTRACE_LDT,
-		 * mm_idp won't belong to current->active_mm, but child->mm.
-		 * So we need to switch child's mm into our userspace, then
-		 * later switch back.
-		 *
-		 * Note: I'm unsure: should interrupts be disabled here?
-		 */
-		if (!current->active_mm || current->active_mm == &init_mm ||
-		    mm_idp != &current->active_mm->context.id)
-			__switch_mm(mm_idp);
-	}
-
-	if (ptrace_ldt) {
-		struct ptrace_ldt ldt_op = (struct ptrace_ldt) {
-			.func = func,
-			.ptr = desc,
-			.bytecount = sizeof(*desc)};
-		u32 cpu;
-		int pid;
-
-		if (!proc_mm)
-			pid = mm_idp->u.pid;
-		else {
-			cpu = get_cpu();
-			pid = userspace_pid[cpu];
-		}
-
-		res = os_ptrace_ldt(pid, 0, (unsigned long) &ldt_op);
-
-		if (proc_mm)
-			put_cpu();
-	}
-	else {
-		void *stub_addr;
-		res = syscall_stub_data(mm_idp, (unsigned long *)desc,
-					(sizeof(*desc) + sizeof(long) - 1) &
-					    ~(sizeof(long) - 1),
-					addr, &stub_addr);
-		if (!res) {
-			unsigned long args[] = { func,
-						 (unsigned long)stub_addr,
-						 sizeof(*desc),
-						 0, 0, 0 };
-			res = run_syscall_stub(mm_idp, __NR_modify_ldt, args,
-					       0, addr, done);
-		}
-	}
-
-	if (proc_mm) {
-		/*
-		 * This is the second part of special handling, that makes
-		 * PTRACE_LDT possible to implement.
-		 */
-		if (current->active_mm && current->active_mm != &init_mm &&
-		    mm_idp != &current->active_mm->context.id)
-			__switch_mm(&current->active_mm->context.id);
-	}
-
-	return res;
-}
-
-static long read_ldt_from_host(void __user * ptr, unsigned long bytecount)
-{
-	int res, n;
-	struct ptrace_ldt ptrace_ldt = (struct ptrace_ldt) {
-			.func = 0,
-			.bytecount = bytecount,
-			.ptr = kmalloc(bytecount, GFP_KERNEL)};
-	u32 cpu;
-
-	if (ptrace_ldt.ptr == NULL)
-		return -ENOMEM;
-
-	/*
-	 * This is called from sys_modify_ldt only, so userspace_pid gives
-	 * us the right number
-	 */
-
-	cpu = get_cpu();
-	res = os_ptrace_ldt(userspace_pid[cpu], 0, (unsigned long) &ptrace_ldt);
-	put_cpu();
-	if (res < 0)
-		goto out;
-
-	n = copy_to_user(ptr, ptrace_ldt.ptr, res);
-	if (n != 0)
-		res = -EFAULT;
-
-  out:
-	kfree(ptrace_ldt.ptr);
-
-	return res;
-}
-
-/*
- * In skas mode, we hold our own ldt data in UML.
- * Thus, the code implementing sys_modify_ldt_skas
- * is very similar to (and mostly stolen from) sys_modify_ldt
- * for arch/i386/kernel/ldt.c
- * The routines copied and modified in part are:
- * - read_ldt
- * - read_default_ldt
- * - write_ldt
- * - sys_modify_ldt_skas
- */
-
-static int read_ldt(void __user * ptr, unsigned long bytecount)
-{
-	int i, err = 0;
-	unsigned long size;
-	uml_ldt_t * ldt = &current->mm->context.ldt;
-
-	if (!ldt->entry_count)
-		goto out;
-	if (bytecount > LDT_ENTRY_SIZE*LDT_ENTRIES)
-		bytecount = LDT_ENTRY_SIZE*LDT_ENTRIES;
-	err = bytecount;
-
-	if (ptrace_ldt)
-		return read_ldt_from_host(ptr, bytecount);
-
-	mutex_lock(&ldt->lock);
-	if (ldt->entry_count <= LDT_DIRECT_ENTRIES) {
-		size = LDT_ENTRY_SIZE*LDT_DIRECT_ENTRIES;
-		if (size > bytecount)
-			size = bytecount;
-		if (copy_to_user(ptr, ldt->u.entries, size))
-			err = -EFAULT;
-		bytecount -= size;
-		ptr += size;
-	}
-	else {
-		for (i=0; i<ldt->entry_count/LDT_ENTRIES_PER_PAGE && bytecount;
-		     i++) {
-			size = PAGE_SIZE;
-			if (size > bytecount)
-				size = bytecount;
-			if (copy_to_user(ptr, ldt->u.pages[i], size)) {
-				err = -EFAULT;
-				break;
-			}
-			bytecount -= size;
-			ptr += size;
-		}
-	}
-	mutex_unlock(&ldt->lock);
-
-	if (bytecount == 0 || err == -EFAULT)
-		goto out;
-
-	if (clear_user(ptr, bytecount))
-		err = -EFAULT;
-
-out:
-	return err;
-}
-
-static int read_default_ldt(void __user * ptr, unsigned long bytecount)
-{
-	int err;
-
-	if (bytecount > 5*LDT_ENTRY_SIZE)
-		bytecount = 5*LDT_ENTRY_SIZE;
-
-	err = bytecount;
-	/*
-	 * UML doesn't support lcall7 and lcall27.
-	 * So, we don't really have a default ldt, but emulate
-	 * an empty ldt of common host default ldt size.
-	 */
-	if (clear_user(ptr, bytecount))
-		err = -EFAULT;
-
-	return err;
-}
-
-static int write_ldt(void __user * ptr, unsigned long bytecount, int func)
-{
-	uml_ldt_t * ldt = &current->mm->context.ldt;
-	struct mm_id * mm_idp = &current->mm->context.id;
-	int i, err;
-	struct user_desc ldt_info;
-	struct ldt_entry entry0, *ldt_p;
-	void *addr = NULL;
-
-	err = -EINVAL;
-	if (bytecount != sizeof(ldt_info))
-		goto out;
-	err = -EFAULT;
-	if (copy_from_user(&ldt_info, ptr, sizeof(ldt_info)))
-		goto out;
-
-	err = -EINVAL;
-	if (ldt_info.entry_number >= LDT_ENTRIES)
-		goto out;
-	if (ldt_info.contents == 3) {
-		if (func == 1)
-			goto out;
-		if (ldt_info.seg_not_present == 0)
-			goto out;
-	}
-
-	if (!ptrace_ldt)
-		mutex_lock(&ldt->lock);
-
-	err = write_ldt_entry(mm_idp, func, &ldt_info, &addr, 1);
-	if (err)
-		goto out_unlock;
-	else if (ptrace_ldt) {
-		/* With PTRACE_LDT available, this is used as a flag only */
-		ldt->entry_count = 1;
-		goto out;
-	}
-
-	if (ldt_info.entry_number >= ldt->entry_count &&
-	    ldt_info.entry_number >= LDT_DIRECT_ENTRIES) {
-		for (i=ldt->entry_count/LDT_ENTRIES_PER_PAGE;
-		     i*LDT_ENTRIES_PER_PAGE <= ldt_info.entry_number;
-		     i++) {
-			if (i == 0)
-				memcpy(&entry0, ldt->u.entries,
-				       sizeof(entry0));
-			ldt->u.pages[i] = (struct ldt_entry *)
-				__get_free_page(GFP_KERNEL|__GFP_ZERO);
-			if (!ldt->u.pages[i]) {
-				err = -ENOMEM;
-				/* Undo the change in host */
-				memset(&ldt_info, 0, sizeof(ldt_info));
-				write_ldt_entry(mm_idp, 1, &ldt_info, &addr, 1);
-				goto out_unlock;
-			}
-			if (i == 0) {
-				memcpy(ldt->u.pages[0], &entry0,
-				       sizeof(entry0));
-				memcpy(ldt->u.pages[0]+1, ldt->u.entries+1,
-				       sizeof(entry0)*(LDT_DIRECT_ENTRIES-1));
-			}
-			ldt->entry_count = (i + 1) * LDT_ENTRIES_PER_PAGE;
-		}
-	}
-	if (ldt->entry_count <= ldt_info.entry_number)
-		ldt->entry_count = ldt_info.entry_number + 1;
-
-	if (ldt->entry_count <= LDT_DIRECT_ENTRIES)
-		ldt_p = ldt->u.entries + ldt_info.entry_number;
-	else
-		ldt_p = ldt->u.pages[ldt_info.entry_number/LDT_ENTRIES_PER_PAGE] +
-			ldt_info.entry_number%LDT_ENTRIES_PER_PAGE;
-
-	if (ldt_info.base_addr == 0 && ldt_info.limit == 0 &&
-	   (func == 1 || LDT_empty(&ldt_info))) {
-		ldt_p->a = 0;
-		ldt_p->b = 0;
-	}
-	else{
-		if (func == 1)
-			ldt_info.useable = 0;
-		ldt_p->a = LDT_entry_a(&ldt_info);
-		ldt_p->b = LDT_entry_b(&ldt_info);
-	}
-	err = 0;
-
-out_unlock:
-	mutex_unlock(&ldt->lock);
-out:
-	return err;
-}
-
-static long do_modify_ldt_skas(int func, void __user *ptr,
-			       unsigned long bytecount)
-{
-	int ret = -ENOSYS;
-
-	switch (func) {
-		case 0:
-			ret = read_ldt(ptr, bytecount);
-			break;
-		case 1:
-		case 0x11:
-			ret = write_ldt(ptr, bytecount, func);
-			break;
-		case 2:
-			ret = read_default_ldt(ptr, bytecount);
-			break;
-	}
-	return ret;
-}
-
-static DEFINE_SPINLOCK(host_ldt_lock);
-static short dummy_list[9] = {0, -1};
-static short * host_ldt_entries = NULL;
-
-static void ldt_get_host_info(void)
-{
-	long ret;
-	struct ldt_entry * ldt;
-	short *tmp;
-	int i, size, k, order;
-
-	spin_lock(&host_ldt_lock);
-
-	if (host_ldt_entries != NULL) {
-		spin_unlock(&host_ldt_lock);
-		return;
-	}
-	host_ldt_entries = dummy_list+1;
-
-	spin_unlock(&host_ldt_lock);
-
-	for (i = LDT_PAGES_MAX-1, order=0; i; i>>=1, order++)
-		;
-
-	ldt = (struct ldt_entry *)
-	      __get_free_pages(GFP_KERNEL|__GFP_ZERO, order);
-	if (ldt == NULL) {
-		printk(KERN_ERR "ldt_get_host_info: couldn't allocate buffer "
-		       "for host ldt\n");
-		return;
-	}
-
-	ret = modify_ldt(0, ldt, (1<<order)*PAGE_SIZE);
-	if (ret < 0) {
-		printk(KERN_ERR "ldt_get_host_info: couldn't read host ldt\n");
-		goto out_free;
-	}
-	if (ret == 0) {
-		/* default_ldt is active, simply write an empty entry 0 */
-		host_ldt_entries = dummy_list;
-		goto out_free;
-	}
-
-	for (i=0, size=0; i<ret/LDT_ENTRY_SIZE; i++) {
-		if (ldt[i].a != 0 || ldt[i].b != 0)
-			size++;
-	}
-
-	if (size < ARRAY_SIZE(dummy_list))
-		host_ldt_entries = dummy_list;
-	else {
-		size = (size + 1) * sizeof(dummy_list[0]);
-		tmp = kmalloc(size, GFP_KERNEL);
-		if (tmp == NULL) {
-			printk(KERN_ERR "ldt_get_host_info: couldn't allocate "
-			       "host ldt list\n");
-			goto out_free;
-		}
-		host_ldt_entries = tmp;
-	}
-
-	for (i=0, k=0; i<ret/LDT_ENTRY_SIZE; i++) {
-		if (ldt[i].a != 0 || ldt[i].b != 0)
-			host_ldt_entries[k++] = i;
-	}
-	host_ldt_entries[k] = -1;
-
-out_free:
-	free_pages((unsigned long)ldt, order);
-}
-
-long init_new_ldt(struct mm_context *new_mm, struct mm_context *from_mm)
-{
-	struct user_desc desc;
-	short * num_p;
-	int i;
-	long page, err=0;
-	void *addr = NULL;
-	struct proc_mm_op copy;
-
-
-	if (!ptrace_ldt)
-		mutex_init(&new_mm->ldt.lock);
-
-	if (!from_mm) {
-		memset(&desc, 0, sizeof(desc));
-		/*
-		 * We have to initialize a clean ldt.
-		 */
-		if (proc_mm) {
-			/*
-			 * If the new mm was created using proc_mm, host's
-			 * default-ldt currently is assigned, which normally
-			 * contains the call-gates for lcall7 and lcall27.
-			 * To remove these gates, we simply write an empty
-			 * entry as number 0 to the host.
-			 */
-			err = write_ldt_entry(&new_mm->id, 1, &desc, &addr, 1);
-		}
-		else{
-			/*
-			 * Now we try to retrieve info about the ldt, we
-			 * inherited from the host. All ldt-entries found
-			 * will be reset in the following loop
-			 */
-			ldt_get_host_info();
-			for (num_p=host_ldt_entries; *num_p != -1; num_p++) {
-				desc.entry_number = *num_p;
-				err = write_ldt_entry(&new_mm->id, 1, &desc,
-						      &addr, *(num_p + 1) == -1);
-				if (err)
-					break;
-			}
-		}
-		new_mm->ldt.entry_count = 0;
-
-		goto out;
-	}
-
-	if (proc_mm) {
-		/*
-		 * We have a valid from_mm, so we now have to copy the LDT of
-		 * from_mm to new_mm, because using proc_mm an new mm with
-		 * an empty/default LDT was created in new_mm()
-		 */
-		copy = ((struct proc_mm_op) { .op 	= MM_COPY_SEGMENTS,
-					      .u 	=
-					      { .copy_segments =
-							from_mm->id.u.mm_fd } } );
-		i = os_write_file(new_mm->id.u.mm_fd, &copy, sizeof(copy));
-		if (i != sizeof(copy))
-			printk(KERN_ERR "new_mm : /proc/mm copy_segments "
-			       "failed, err = %d\n", -i);
-	}
-
-	if (!ptrace_ldt) {
-		/*
-		 * Our local LDT is used to supply the data for
-		 * modify_ldt(READLDT), if PTRACE_LDT isn't available,
-		 * i.e., we have to use the stub for modify_ldt, which
-		 * can't handle the big read buffer of up to 64kB.
-		 */
-		mutex_lock(&from_mm->ldt.lock);
-		if (from_mm->ldt.entry_count <= LDT_DIRECT_ENTRIES)
-			memcpy(new_mm->ldt.u.entries, from_mm->ldt.u.entries,
-			       sizeof(new_mm->ldt.u.entries));
-		else {
-			i = from_mm->ldt.entry_count / LDT_ENTRIES_PER_PAGE;
-			while (i-->0) {
-				page = __get_free_page(GFP_KERNEL|__GFP_ZERO);
-				if (!page) {
-					err = -ENOMEM;
-					break;
-				}
-				new_mm->ldt.u.pages[i] =
-					(struct ldt_entry *) page;
-				memcpy(new_mm->ldt.u.pages[i],
-				       from_mm->ldt.u.pages[i], PAGE_SIZE);
-			}
-		}
-		new_mm->ldt.entry_count = from_mm->ldt.entry_count;
-		mutex_unlock(&from_mm->ldt.lock);
-	}
-
-    out:
-	return err;
-}
-
-
-void free_ldt(struct mm_context *mm)
-{
-	int i;
-
-	if (!ptrace_ldt && mm->ldt.entry_count > LDT_DIRECT_ENTRIES) {
-		i = mm->ldt.entry_count / LDT_ENTRIES_PER_PAGE;
-		while (i-- > 0)
-			free_page((long) mm->ldt.u.pages[i]);
-	}
-	mm->ldt.entry_count = 0;
-}
-
-int sys_modify_ldt(int func, void __user *ptr, unsigned long bytecount)
-{
-	return do_modify_ldt_skas(func, ptr, bytecount);
-}