Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750813AbWAOUsJ (ORCPT ); Sun, 15 Jan 2006 15:48:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750795AbWAOUr6 (ORCPT ); Sun, 15 Jan 2006 15:47:58 -0500 Received: from saraswathi.solana.com ([198.99.130.12]:28323 "EHLO saraswathi.solana.com") by vger.kernel.org with ESMTP id S1750760AbWAOUrw (ORCPT ); Sun, 15 Jan 2006 15:47:52 -0500 Message-Id: <200601152139.k0FLdWvO027705@ccure.user-mode-linux.org> X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.0.4 To: akpm@osdl.org cc: linux-kernel@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net, Bodo Stroesser Subject: [PATCH 1/11] UML - Move LDT creation Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sun, 15 Jan 2006 16:39:32 -0500 From: Jeff Dike Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5548 Lines: 163 From: Bodo Stroesser s390 doesn't have a LDT. So MM_COPY_SEGMENTS will not be supported on s390. The only user of MM_COPY_SEGMENTS is new_mm(), but that's no longer useful, as arch/sys-i386/ldt.c defines init_new_ldt(), which is called immediately after new_mm(). So we should copy host's LDT in init_new_ldt(), if /proc/mm is available, to have this subarch specific call in subarch code. Signed-off-by: Bodo Stroesser Signed-off-by: Jeff Dike Index: linux-2.6.15/arch/um/kernel/skas/include/skas.h =================================================================== --- linux-2.6.15.orig/arch/um/kernel/skas/include/skas.h 2006-01-05 16:19:59.000000000 -0500 +++ linux-2.6.15/arch/um/kernel/skas/include/skas.h 2006-01-05 21:26:43.000000000 -0500 @@ -33,7 +33,7 @@ extern int protect(struct mm_id * mm_idp unsigned long len, int r, int w, int x, int done, void **data); extern void user_signal(int sig, union uml_pt_regs *regs, int pid); -extern int new_mm(int from, unsigned long stack); +extern int new_mm(unsigned long stack); extern int start_userspace(unsigned long stub_stack); extern int copy_context_skas0(unsigned long stack, int pid); extern void get_skas_faultinfo(int pid, struct faultinfo * fi); Index: linux-2.6.15/arch/um/kernel/skas/mmu.c =================================================================== --- linux-2.6.15.orig/arch/um/kernel/skas/mmu.c 2006-01-03 17:39:46.000000000 -0500 +++ linux-2.6.15/arch/um/kernel/skas/mmu.c 2006-01-05 21:26:43.000000000 -0500 @@ -78,7 +78,7 @@ int init_new_context_skas(struct task_st struct mmu_context_skas *from_mm = NULL; struct mmu_context_skas *to_mm = &mm->context.skas; unsigned long stack = 0; - int from_fd, ret = -ENOMEM; + int ret = -ENOMEM; if(skas_needs_stub){ stack = get_zeroed_page(GFP_KERNEL); @@ -108,11 +108,7 @@ int init_new_context_skas(struct task_st from_mm = ¤t->mm->context.skas; if(proc_mm){ - if(from_mm) - from_fd = from_mm->id.u.mm_fd; - else from_fd = -1; - - ret = new_mm(from_fd, stack); + ret = new_mm(stack); if(ret < 0){ printk("init_new_context_skas - new_mm failed, " "errno = %d\n", ret); Index: linux-2.6.15/arch/um/kernel/skas/process_kern.c =================================================================== --- linux-2.6.15.orig/arch/um/kernel/skas/process_kern.c 2006-01-05 16:19:59.000000000 -0500 +++ linux-2.6.15/arch/um/kernel/skas/process_kern.c 2006-01-05 21:26:43.000000000 -0500 @@ -20,7 +20,6 @@ #include "tlb.h" #include "kern.h" #include "mode.h" -#include "proc_mm.h" #include "registers.h" void switch_to_skas(void *prev, void *next) @@ -125,25 +124,14 @@ int copy_thread_skas(int nr, unsigned lo extern void map_stub_pages(int fd, unsigned long code, unsigned long data, unsigned long stack); -int new_mm(int from, unsigned long stack) +int new_mm(unsigned long stack) { - struct proc_mm_op copy; - int n, fd; + int fd; fd = os_open_file("/proc/mm", of_cloexec(of_write(OPENFLAGS())), 0); if(fd < 0) return(fd); - if(from != -1){ - copy = ((struct proc_mm_op) { .op = MM_COPY_SEGMENTS, - .u = - { .copy_segments = from } } ); - n = os_write_file(fd, ©, sizeof(copy)); - if(n != sizeof(copy)) - printk("new_mm : /proc/mm copy_segments failed, " - "err = %d\n", -n); - } - if(skas_needs_stub) map_stub_pages(fd, CONFIG_STUB_CODE, CONFIG_STUB_DATA, stack); Index: linux-2.6.15/arch/um/sys-i386/ldt.c =================================================================== --- linux-2.6.15.orig/arch/um/sys-i386/ldt.c 2006-01-03 17:39:46.000000000 -0500 +++ linux-2.6.15/arch/um/sys-i386/ldt.c 2006-01-05 21:26:43.000000000 -0500 @@ -16,6 +16,8 @@ #include "choose-mode.h" #include "kern.h" #include "mode_kern.h" +#include "proc_mm.h" +#include "os.h" extern int modify_ldt(int func, void *ptr, unsigned long bytecount); @@ -456,13 +458,14 @@ long init_new_ldt(struct mmu_context_ska int i; long page, err=0; void *addr = NULL; + struct proc_mm_op copy; - memset(&desc, 0, sizeof(desc)); if(!ptrace_ldt) init_MUTEX(&new_mm->ldt.semaphore); if(!from_mm){ + memset(&desc, 0, sizeof(desc)); /* * We have to initialize a clean ldt. */ @@ -494,8 +497,26 @@ long init_new_ldt(struct mmu_context_ska } } new_mm->ldt.entry_count = 0; + + goto out; } - else if (!ptrace_ldt) { + + 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, ©, sizeof(copy)); + if(i != sizeof(copy)) + printk("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 @@ -524,6 +545,7 @@ long init_new_ldt(struct mmu_context_ska up(&from_mm->ldt.semaphore); } + out: return err; } - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/