Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756828AbXKUWkL (ORCPT ); Wed, 21 Nov 2007 17:40:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752680AbXKUWj6 (ORCPT ); Wed, 21 Nov 2007 17:39:58 -0500 Received: from mx1.redhat.com ([66.187.233.31]:34012 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753518AbXKUWj5 (ORCPT ); Wed, 21 Nov 2007 17:39:57 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Zachary Amsden X-Fcc: ~/Mail/linus Cc: Andrew Morton , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , linux-kernel@vger.kernel.org Subject: [replacement PATCH 6/6] x86: TLS cleanup In-Reply-To: Zachary Amsden's message of Wednesday, 21 November 2007 10:34:39 -0800 <1195670079.6352.252.camel@bodhitayantram.eng.vmware.com> References: <20071121101928.A08CF26F8BE@magilla.localdomain> <20071121102511.08B8A26F8BE@magilla.localdomain> <1195670079.6352.252.camel@bodhitayantram.eng.vmware.com> X-Shopping-List: (1) Fallacious anthropomorphic abstention annoyers (2) Harried exhibitions (3) Salubrious trans-Atlantic convulsion commotions (4) Responsible dwarf thunder Message-Id: <20071121223951.2A6F526F8BE@magilla.localdomain> Date: Wed, 21 Nov 2007 14:39:51 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 17794 Lines: 598 This consolidates the four different places that implemented the same encoding magic for the GDT-slot 32-bit TLS support. The old tls32.c was renamed and is now only slightly modified to be the shared implementation. Signed-off-by: Roland McGrath --- arch/x86/ia32/ia32entry.S | 4 +- arch/x86/kernel/Makefile_32 | 1 + arch/x86/kernel/process_32.c | 143 ++---------------------------------------- arch/x86/kernel/process_64.c | 3 +- arch/x86/kernel/ptrace_32.c | 91 +++------------------------ arch/x86/kernel/ptrace_64.c | 26 +++----- arch/x86/kernel/tls.c | 97 +++++++++++----------------- include/asm-x86/ia32.h | 6 -- include/asm-x86/ptrace.h | 11 +++ 9 files changed, 80 insertions(+), 302 deletions(-) diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index df588f0..0a71fa9 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -644,8 +644,8 @@ ia32_sys_call_table: .quad compat_sys_futex /* 240 */ .quad compat_sys_sched_setaffinity .quad compat_sys_sched_getaffinity - .quad sys32_set_thread_area - .quad sys32_get_thread_area + .quad sys_set_thread_area + .quad sys_get_thread_area .quad compat_sys_io_setup /* 245 */ .quad sys_io_destroy .quad compat_sys_io_getevents diff --git a/arch/x86/kernel/Makefile_32 b/arch/x86/kernel/Makefile_32 index a7bc93c..e660584 100644 --- a/arch/x86/kernel/Makefile_32 +++ b/arch/x86/kernel/Makefile_32 @@ -10,6 +10,7 @@ obj-y := process_32.o signal_32.o entry_32.o traps_32.o irq_32.o \ pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\ quirks.o i8237.o topology.o alternative.o i8253.o tsc_32.o +obj-y += tls.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-y += cpu/ obj-y += acpi/ diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 7b89958..ebbbfc5 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -480,33 +480,16 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long esp, set_tsk_thread_flag(p, TIF_IO_BITMAP); } + err = 0; + /* * Set a new TLS for the child thread? */ - if (clone_flags & CLONE_SETTLS) { - struct desc_struct *desc; - struct user_desc info; - int idx; - - err = -EFAULT; - if (copy_from_user(&info, (void __user *)childregs->esi, sizeof(info))) - goto out; - err = -EINVAL; - if (LDT_empty(&info)) - goto out; - - idx = info.entry_number; - if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) - goto out; - - desc = p->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; - desc->a = LDT_entry_a(&info); - desc->b = LDT_entry_b(&info); - } + if (clone_flags & CLONE_SETTLS) + err = do_set_thread_area(p, -1, + (struct user_desc __user *)childregs->esi, 0); - err = 0; - out: - if (err && p->thread.io_bitmap_ptr) { + if (err && p->thread.io_bitmap_ptr) { kfree(p->thread.io_bitmap_ptr); p->thread.io_bitmap_max = 0; } @@ -851,120 +834,6 @@ unsigned long get_wchan(struct task_struct *p) return 0; } -/* - * sys_alloc_thread_area: get a yet unused TLS descriptor index. - */ -static int get_free_idx(void) -{ - struct thread_struct *t = ¤t->thread; - int idx; - - for (idx = 0; idx < GDT_ENTRY_TLS_ENTRIES; idx++) - if (desc_empty(t->tls_array + idx)) - return idx + GDT_ENTRY_TLS_MIN; - return -ESRCH; -} - -/* - * Set a given TLS descriptor: - */ -asmlinkage int sys_set_thread_area(struct user_desc __user *u_info) -{ - struct thread_struct *t = ¤t->thread; - struct user_desc info; - struct desc_struct *desc; - int cpu, idx; - - if (copy_from_user(&info, u_info, sizeof(info))) - return -EFAULT; - idx = info.entry_number; - - /* - * index -1 means the kernel should try to find and - * allocate an empty descriptor: - */ - if (idx == -1) { - idx = get_free_idx(); - if (idx < 0) - return idx; - if (put_user(idx, &u_info->entry_number)) - return -EFAULT; - } - - if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) - return -EINVAL; - - desc = t->tls_array + idx - GDT_ENTRY_TLS_MIN; - - /* - * We must not get preempted while modifying the TLS. - */ - cpu = get_cpu(); - - if (LDT_empty(&info)) { - desc->a = 0; - desc->b = 0; - } else { - desc->a = LDT_entry_a(&info); - desc->b = LDT_entry_b(&info); - } - load_TLS(t, cpu); - - put_cpu(); - - return 0; -} - -/* - * Get the current Thread-Local Storage area: - */ - -#define GET_BASE(desc) ( \ - (((desc)->a >> 16) & 0x0000ffff) | \ - (((desc)->b << 16) & 0x00ff0000) | \ - ( (desc)->b & 0xff000000) ) - -#define GET_LIMIT(desc) ( \ - ((desc)->a & 0x0ffff) | \ - ((desc)->b & 0xf0000) ) - -#define GET_32BIT(desc) (((desc)->b >> 22) & 1) -#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3) -#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1) -#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1) -#define GET_PRESENT(desc) (((desc)->b >> 15) & 1) -#define GET_USEABLE(desc) (((desc)->b >> 20) & 1) - -asmlinkage int sys_get_thread_area(struct user_desc __user *u_info) -{ - struct user_desc info; - struct desc_struct *desc; - int idx; - - if (get_user(idx, &u_info->entry_number)) - return -EFAULT; - if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) - return -EINVAL; - - memset(&info, 0, sizeof(info)); - - desc = current->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; - - info.entry_number = idx; - info.base_addr = GET_BASE(desc); - info.limit = GET_LIMIT(desc); - info.seg_32bit = GET_32BIT(desc); - info.contents = GET_CONTENTS(desc); - info.read_exec_only = !GET_WRITABLE(desc); - info.limit_in_pages = GET_LIMIT_PAGES(desc); - info.seg_not_present = !GET_PRESENT(desc); - info.useable = GET_USEABLE(desc); - - if (copy_to_user(u_info, &info, sizeof(info))) - return -EFAULT; - return 0; -} - unsigned long arch_align_stack(unsigned long sp) { if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index b8d131d..3fdbf78 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -513,7 +513,8 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp, if (clone_flags & CLONE_SETTLS) { #ifdef CONFIG_IA32_EMULATION if (test_thread_flag(TIF_IA32)) - err = ia32_child_tls(p, childregs); + err = do_set_thread_area(p, -1, + (struct user_desc __user *)childregs->rsi, 0); else #endif err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8); diff --git a/arch/x86/kernel/ptrace_32.c b/arch/x86/kernel/ptrace_32.c index ff5431c..39a94a0 100644 --- a/arch/x86/kernel/ptrace_32.c +++ b/arch/x86/kernel/ptrace_32.c @@ -276,85 +276,6 @@ void ptrace_disable(struct task_struct *child) clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); } -/* - * Perform get_thread_area on behalf of the traced child. - */ -static int -ptrace_get_thread_area(struct task_struct *child, - int idx, struct user_desc __user *user_desc) -{ - struct user_desc info; - struct desc_struct *desc; - -/* - * Get the current Thread-Local Storage area: - */ - -#define GET_BASE(desc) ( \ - (((desc)->a >> 16) & 0x0000ffff) | \ - (((desc)->b << 16) & 0x00ff0000) | \ - ( (desc)->b & 0xff000000) ) - -#define GET_LIMIT(desc) ( \ - ((desc)->a & 0x0ffff) | \ - ((desc)->b & 0xf0000) ) - -#define GET_32BIT(desc) (((desc)->b >> 22) & 1) -#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3) -#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1) -#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1) -#define GET_PRESENT(desc) (((desc)->b >> 15) & 1) -#define GET_USEABLE(desc) (((desc)->b >> 20) & 1) - - if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) - return -EINVAL; - - desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; - - info.entry_number = idx; - info.base_addr = GET_BASE(desc); - info.limit = GET_LIMIT(desc); - info.seg_32bit = GET_32BIT(desc); - info.contents = GET_CONTENTS(desc); - info.read_exec_only = !GET_WRITABLE(desc); - info.limit_in_pages = GET_LIMIT_PAGES(desc); - info.seg_not_present = !GET_PRESENT(desc); - info.useable = GET_USEABLE(desc); - - if (copy_to_user(user_desc, &info, sizeof(info))) - return -EFAULT; - - return 0; -} - -/* - * Perform set_thread_area on behalf of the traced child. - */ -static int -ptrace_set_thread_area(struct task_struct *child, - int idx, struct user_desc __user *user_desc) -{ - struct user_desc info; - struct desc_struct *desc; - - if (copy_from_user(&info, user_desc, sizeof(info))) - return -EFAULT; - - if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) - return -EINVAL; - - desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; - if (LDT_empty(&info)) { - desc->a = 0; - desc->b = 0; - } else { - desc->a = LDT_entry_a(&info); - desc->b = LDT_entry_b(&info); - } - - return 0; -} - long arch_ptrace(struct task_struct *child, long request, long addr, long data) { struct user * dummy = NULL; @@ -601,13 +522,17 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) } case PTRACE_GET_THREAD_AREA: - ret = ptrace_get_thread_area(child, addr, - (struct user_desc __user *) data); + if (addr < 0) + return -EIO; + ret = do_get_thread_area(child, addr, + (struct user_desc __user *) data); break; case PTRACE_SET_THREAD_AREA: - ret = ptrace_set_thread_area(child, addr, - (struct user_desc __user *) data); + if (addr < 0) + return -EIO; + ret = do_set_thread_area(child, addr, + (struct user_desc __user *) data, 0); break; default: diff --git a/arch/x86/kernel/ptrace_64.c b/arch/x86/kernel/ptrace_64.c index 3ff7ddc..07de75d 100644 --- a/arch/x86/kernel/ptrace_64.c +++ b/arch/x86/kernel/ptrace_64.c @@ -474,23 +474,19 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) 64bit debugger to fully examine them too. Better don't use it against 64bit processes, use PTRACE_ARCH_PRCTL instead. */ - case PTRACE_SET_THREAD_AREA: { - struct user_desc __user *p; - int old; - p = (struct user_desc __user *)data; - get_user(old, &p->entry_number); - put_user(addr, &p->entry_number); - ret = do_set_thread_area(&child->thread, p); - put_user(old, &p->entry_number); - break; case PTRACE_GET_THREAD_AREA: - p = (struct user_desc __user *)data; - get_user(old, &p->entry_number); - put_user(addr, &p->entry_number); - ret = do_get_thread_area(&child->thread, p); - put_user(old, &p->entry_number); + if (addr < 0) + return -EIO; + ret = do_get_thread_area(child, addr, + (struct user_desc __user *) data); + + break; + case PTRACE_SET_THREAD_AREA: + if (addr < 0) + return -EIO; + ret = do_set_thread_area(child, addr, + (struct user_desc __user *) data, 0); break; - } #endif /* normal 64bit interface to access TLS data. Works just like arch_prctl, except that the arguments diff --git a/arch/x86/kernel/tls.c b/arch/x86/kernel/tls.c index 5291596..0a1a744 100644 --- a/arch/x86/kernel/tls.c +++ b/arch/x86/kernel/tls.c @@ -19,31 +19,34 @@ static int get_free_idx(void) int idx; for (idx = 0; idx < GDT_ENTRY_TLS_ENTRIES; idx++) - if (desc_empty((struct n_desc_struct *)(t->tls_array) + idx)) + if (desc_empty(&t->tls_array[idx])) return idx + GDT_ENTRY_TLS_MIN; return -ESRCH; } /* * Set a given TLS descriptor: - * When you want addresses > 32bit use arch_prctl() */ -int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) +int do_set_thread_area(struct task_struct *p, int idx, + struct user_desc __user *u_info, + int can_allocate) { + struct thread_struct *t = &p->thread; struct user_desc info; - struct n_desc_struct *desc; - int cpu, idx; + u32 *desc; + int cpu; if (copy_from_user(&info, u_info, sizeof(info))) return -EFAULT; - idx = info.entry_number; + if (idx == -1) + idx = info.entry_number; /* * index -1 means the kernel should try to find and * allocate an empty descriptor: */ - if (idx == -1) { + if (idx == -1 && can_allocate) { idx = get_free_idx(); if (idx < 0) return idx; @@ -54,7 +57,7 @@ int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) return -EINVAL; - desc = ((struct n_desc_struct *)t->tls_array) + idx - GDT_ENTRY_TLS_MIN; + desc = (u32 *) &t->tls_array[idx - GDT_ENTRY_TLS_MIN]; /* * We must not get preempted while modifying the TLS. @@ -62,11 +65,11 @@ int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) cpu = get_cpu(); if (LDT_empty(&info)) { - desc->a = 0; - desc->b = 0; + desc[0] = 0; + desc[1] = 0; } else { - desc->a = LDT_entry_a(&info); - desc->b = LDT_entry_b(&info); + desc[0] = LDT_entry_a(&info); + desc[1] = LDT_entry_b(&info); } if (t == ¤t->thread) load_TLS(t, cpu); @@ -75,9 +78,9 @@ int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info) return 0; } -asmlinkage long sys32_set_thread_area(struct user_desc __user *u_info) +asmlinkage int sys_set_thread_area(struct user_desc __user *u_info) { - return do_set_thread_area(¤t->thread, u_info); + return do_set_thread_area(current, -1, u_info, 1); } @@ -86,33 +89,34 @@ asmlinkage long sys32_set_thread_area(struct user_desc __user *u_info) */ #define GET_LIMIT(desc) ( \ - ((desc)->a & 0x0ffff) | \ - ((desc)->b & 0xf0000) ) - -#define GET_32BIT(desc) (((desc)->b >> 22) & 1) -#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3) -#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1) -#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1) -#define GET_PRESENT(desc) (((desc)->b >> 15) & 1) -#define GET_USEABLE(desc) (((desc)->b >> 20) & 1) -#define GET_LONGMODE(desc) (((desc)->b >> 21) & 1) - -int do_get_thread_area(struct thread_struct *t, struct user_desc __user *u_info) + ((desc)[0] & 0x0ffff) | \ + ((desc)[1] & 0xf0000) ) + +#define GET_32BIT(desc) (((desc)[1] >> 22) & 1) +#define GET_CONTENTS(desc) (((desc)[1] >> 10) & 3) +#define GET_WRITABLE(desc) (((desc)[1] >> 9) & 1) +#define GET_LIMIT_PAGES(desc) (((desc)[1] >> 23) & 1) +#define GET_PRESENT(desc) (((desc)[1] >> 15) & 1) +#define GET_USEABLE(desc) (((desc)[1] >> 20) & 1) +#define GET_LONGMODE(desc) (((desc)[1] >> 21) & 1) + +int do_get_thread_area(struct task_struct *p, int idx, + struct user_desc __user *u_info) { + struct thread_struct *t = &p->thread; struct user_desc info; - struct n_desc_struct *desc; - int idx; + u32 *desc; - if (get_user(idx, &u_info->entry_number)) + if (idx == -1 && get_user(idx, &u_info->entry_number)) return -EFAULT; if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) return -EINVAL; - desc = ((struct n_desc_struct *)t->tls_array) + idx - GDT_ENTRY_TLS_MIN; + desc = (u32 *) &t->tls_array[idx - GDT_ENTRY_TLS_MIN]; memset(&info, 0, sizeof(struct user_desc)); info.entry_number = idx; - info.base_addr = get_desc_base(desc); + info.base_addr = get_desc_base((void *)desc); info.limit = GET_LIMIT(desc); info.seg_32bit = GET_32BIT(desc); info.contents = GET_CONTENTS(desc); @@ -120,39 +124,16 @@ int do_get_thread_area(struct thread_struct *t, struct user_desc __user *u_info) info.limit_in_pages = GET_LIMIT_PAGES(desc); info.seg_not_present = !GET_PRESENT(desc); info.useable = GET_USEABLE(desc); +#ifdef CONFIG_X86_64 info.lm = GET_LONGMODE(desc); +#endif if (copy_to_user(u_info, &info, sizeof(info))) return -EFAULT; return 0; } -asmlinkage long sys32_get_thread_area(struct user_desc __user *u_info) -{ - return do_get_thread_area(¤t->thread, u_info); -} - - -int ia32_child_tls(struct task_struct *p, struct pt_regs *childregs) +asmlinkage int sys_get_thread_area(struct user_desc __user *u_info) { - struct n_desc_struct *desc; - struct user_desc info; - struct user_desc __user *cp; - int idx; - - cp = (void __user *)childregs->rsi; - if (copy_from_user(&info, cp, sizeof(info))) - return -EFAULT; - if (LDT_empty(&info)) - return -EINVAL; - - idx = info.entry_number; - if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) - return -EINVAL; - - desc = (struct n_desc_struct *)(p->thread.tls_array) + idx - GDT_ENTRY_TLS_MIN; - desc->a = LDT_entry_a(&info); - desc->b = LDT_entry_b(&info); - - return 0; + return do_get_thread_area(current, -1, u_info); } diff --git a/include/asm-x86/ia32.h b/include/asm-x86/ia32.h index 0190b7c..aa97332 100644 --- a/include/asm-x86/ia32.h +++ b/include/asm-x86/ia32.h @@ -159,12 +159,6 @@ struct ustat32 { #define IA32_STACK_TOP IA32_PAGE_OFFSET #ifdef __KERNEL__ -struct user_desc; -struct siginfo_t; -int do_get_thread_area(struct thread_struct *t, struct user_desc __user *info); -int do_set_thread_area(struct thread_struct *t, struct user_desc __user *info); -int ia32_child_tls(struct task_struct *p, struct pt_regs *childregs); - struct linux_binprm; extern int ia32_setup_arg_pages(struct linux_binprm *bprm, unsigned long stack_top, int exec_stack); diff --git a/include/asm-x86/ptrace.h b/include/asm-x86/ptrace.h index 51ddb25..105d153 100644 --- a/include/asm-x86/ptrace.h +++ b/include/asm-x86/ptrace.h @@ -137,6 +137,17 @@ enum { }; #endif /* __KERNEL__ */ #endif /* !__i386__ */ + +#ifdef __KERNEL__ + +struct user_desc; +extern int do_get_thread_area(struct task_struct *p, int idx, + struct user_desc __user *info); +extern int do_set_thread_area(struct task_struct *p, int idx, + struct user_desc __user *info, int can_allocate); + +#endif /* __KERNEL__ */ + #endif /* !__ASSEMBLY__ */ #endif - 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/