diff options
| -rw-r--r-- | arch/tile/Kconfig | 3 | ||||
| -rw-r--r-- | arch/tile/include/asm/elf.h | 5 | ||||
| -rw-r--r-- | arch/tile/include/asm/mmu.h | 1 | ||||
| -rw-r--r-- | arch/tile/include/asm/page.h | 8 | ||||
| -rw-r--r-- | arch/tile/include/asm/processor.h | 6 | ||||
| -rw-r--r-- | arch/tile/include/asm/sections.h | 4 | ||||
| -rw-r--r-- | arch/tile/include/asm/vdso.h | 49 | ||||
| -rw-r--r-- | arch/tile/include/uapi/asm/auxvec.h | 3 | ||||
| -rw-r--r-- | arch/tile/kernel/Makefile | 4 | ||||
| -rw-r--r-- | arch/tile/kernel/compat_signal.c | 3 | ||||
| -rw-r--r-- | arch/tile/kernel/entry.S | 16 | ||||
| -rw-r--r-- | arch/tile/kernel/signal.c | 3 | ||||
| -rw-r--r-- | arch/tile/kernel/stack.c | 5 | ||||
| -rw-r--r-- | arch/tile/kernel/time.c | 37 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso.c | 212 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/Makefile | 118 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vdso.S | 28 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vdso.lds.S | 87 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vdso32.S | 28 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vgettimeofday.c | 107 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vrt_sigreturn.S | 30 | ||||
| -rw-r--r-- | arch/tile/mm/elf.c | 37 |
22 files changed, 732 insertions, 62 deletions
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig index 1126b9d2f4cc..7b87318ee690 100644 --- a/arch/tile/Kconfig +++ b/arch/tile/Kconfig @@ -64,6 +64,9 @@ config HUGETLB_SUPER_PAGES depends on HUGETLB_PAGE && TILEGX def_bool y +config GENERIC_TIME_VSYSCALL + def_bool y + # FIXME: tilegx can implement a more efficient rwsem. config RWSEM_GENERIC_SPINLOCK def_bool y diff --git a/arch/tile/include/asm/elf.h b/arch/tile/include/asm/elf.h index ff8a93408823..31d854f1b83b 100644 --- a/arch/tile/include/asm/elf.h +++ b/arch/tile/include/asm/elf.h @@ -132,6 +132,11 @@ extern int dump_task_regs(struct task_struct *, elf_gregset_t *); struct linux_binprm; extern int arch_setup_additional_pages(struct linux_binprm *bprm, int executable_stack); +#define ARCH_DLINFO \ +do { \ + NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_BASE); \ +} while (0) + #ifdef CONFIG_COMPAT #define COMPAT_ELF_PLATFORM "tilegx-m32" diff --git a/arch/tile/include/asm/mmu.h b/arch/tile/include/asm/mmu.h index e2c789096795..0cab1182bde1 100644 --- a/arch/tile/include/asm/mmu.h +++ b/arch/tile/include/asm/mmu.h @@ -22,6 +22,7 @@ struct mm_context { * semaphore but atomically, but it is conservatively set. */ unsigned long priority_cached; + unsigned long vdso_base; }; typedef struct mm_context mm_context_t; diff --git a/arch/tile/include/asm/page.h b/arch/tile/include/asm/page.h index dd033a4fd627..b4f96c0024df 100644 --- a/arch/tile/include/asm/page.h +++ b/arch/tile/include/asm/page.h @@ -39,6 +39,12 @@ #define HPAGE_MASK (~(HPAGE_SIZE - 1)) /* + * We do define AT_SYSINFO_EHDR to support vDSO, + * but don't use the gate mechanism. + */ +#define __HAVE_ARCH_GATE_AREA 1 + +/* * If the Kconfig doesn't specify, set a maximum zone order that * is enough so that we can create huge pages from small pages given * the respective sizes of the two page types. See <linux/mmzone.h>. @@ -246,7 +252,7 @@ static inline __attribute_const__ int get_order(unsigned long size) #endif /* __tilegx__ */ -#ifndef __ASSEMBLY__ +#if !defined(__ASSEMBLY__) && !defined(VDSO_BUILD) #ifdef CONFIG_HIGHMEM diff --git a/arch/tile/include/asm/processor.h b/arch/tile/include/asm/processor.h index fed1c044fec8..461322b473b5 100644 --- a/arch/tile/include/asm/processor.h +++ b/arch/tile/include/asm/processor.h @@ -180,10 +180,10 @@ struct thread_struct { #define TASK_SIZE TASK_SIZE_MAX #endif -/* We provide a minimal "vdso" a la x86; just the sigreturn code for now. */ -#define VDSO_BASE (TASK_SIZE - PAGE_SIZE) +#define VDSO_BASE ((unsigned long)current->active_mm->context.vdso_base) +#define VDSO_SYM(x) (VDSO_BASE + (unsigned long)(x)) -#define STACK_TOP VDSO_BASE +#define STACK_TOP TASK_SIZE /* STACK_TOP_MAX is used temporarily in execve and should not check COMPAT. */ #define STACK_TOP_MAX TASK_SIZE_MAX diff --git a/arch/tile/include/asm/sections.h b/arch/tile/include/asm/sections.h index cc95276ef9c9..5d5d3b739a6b 100644 --- a/arch/tile/include/asm/sections.h +++ b/arch/tile/include/asm/sections.h @@ -25,6 +25,10 @@ extern char _sinitdata[], _einitdata[]; /* Write-once data is writable only till the end of initialization. */ extern char __w1data_begin[], __w1data_end[]; +extern char vdso_start[], vdso_end[]; +#ifdef CONFIG_COMPAT +extern char vdso32_start[], vdso32_end[]; +#endif /* Not exactly sections, but PC comparison points in the code. */ extern char __rt_sigreturn[], __rt_sigreturn_end[]; diff --git a/arch/tile/include/asm/vdso.h b/arch/tile/include/asm/vdso.h new file mode 100644 index 000000000000..9f6a78d665fa --- /dev/null +++ b/arch/tile/include/asm/vdso.h @@ -0,0 +1,49 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#ifndef __TILE_VDSO_H__ +#define __TILE_VDSO_H__ + +#include <linux/types.h> + +/* + * Note about the vdso_data structure: + * + * NEVER USE THEM IN USERSPACE CODE DIRECTLY. The layout of the + * structure is supposed to be known only to the function in the vdso + * itself and may change without notice. + */ + +struct vdso_data { + __u64 tz_update_count; /* Timezone atomicity ctr */ + __u64 tb_update_count; /* Timebase atomicity ctr */ + __u64 xtime_tod_stamp; /* TOD clock for xtime */ + __u64 xtime_clock_sec; /* Kernel time second */ + __u64 xtime_clock_nsec; /* Kernel time nanosecond */ + __u64 wtom_clock_sec; /* Wall to monotonic clock second */ + __u64 wtom_clock_nsec; /* Wall to monotonic clock nanosecond */ + __u32 mult; /* Cycle to nanosecond multiplier */ + __u32 shift; /* Cycle to nanosecond divisor (power of two) */ + __u32 tz_minuteswest; /* Minutes west of Greenwich */ + __u32 tz_dsttime; /* Type of dst correction */ +}; + +extern struct vdso_data *vdso_data; + +/* __vdso_rt_sigreturn is defined with the addresses in the vdso page. */ +extern void __vdso_rt_sigreturn(void); + +extern int setup_vdso_pages(void); + +#endif /* __TILE_VDSO_H__ */ diff --git a/arch/tile/include/uapi/asm/auxvec.h b/arch/tile/include/uapi/asm/auxvec.h index 1d393edb0641..c93e92709f14 100644 --- a/arch/tile/include/uapi/asm/auxvec.h +++ b/arch/tile/include/uapi/asm/auxvec.h @@ -15,6 +15,7 @@ #ifndef _ASM_TILE_AUXVEC_H #define _ASM_TILE_AUXVEC_H -/* No extensions to auxvec */ +/* The vDSO location. */ +#define AT_SYSINFO_EHDR 33 #endif /* _ASM_TILE_AUXVEC_H */ diff --git a/arch/tile/kernel/Makefile b/arch/tile/kernel/Makefile index 6846c4ef5bf1..5157d1c4b4ed 100644 --- a/arch/tile/kernel/Makefile +++ b/arch/tile/kernel/Makefile @@ -6,7 +6,7 @@ extra-y := vmlinux.lds head_$(BITS).o obj-y := backtrace.o entry.o irq.o messaging.o \ pci-dma.o proc.o process.o ptrace.o reboot.o \ setup.o signal.o single_step.o stack.o sys.o \ - sysfs.o time.o traps.o unaligned.o \ + sysfs.o time.o traps.o unaligned.o vdso.o \ intvec_$(BITS).o regs_$(BITS).o tile-desc_$(BITS).o obj-$(CONFIG_HARDWALL) += hardwall.o @@ -21,3 +21,5 @@ else obj-$(CONFIG_PCI) += pci.o endif obj-$(CONFIG_TILE_USB) += usb.o + +obj-y += vdso/ diff --git a/arch/tile/kernel/compat_signal.c b/arch/tile/kernel/compat_signal.c index d0a052e725be..85e00b2f39bf 100644 --- a/arch/tile/kernel/compat_signal.c +++ b/arch/tile/kernel/compat_signal.c @@ -32,6 +32,7 @@ #include <asm/ucontext.h> #include <asm/sigframe.h> #include <asm/syscalls.h> +#include <asm/vdso.h> #include <arch/interrupts.h> struct compat_ucontext { @@ -227,7 +228,7 @@ int compat_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, if (err) goto give_sigsegv; - restorer = VDSO_BASE; + restorer = VDSO_SYM(&__vdso_rt_sigreturn); if (ka->sa.sa_flags & SA_RESTORER) restorer = ptr_to_compat_reg(ka->sa.sa_restorer); diff --git a/arch/tile/kernel/entry.S b/arch/tile/kernel/entry.S index f116cb0bce20..3d9175992a20 100644 --- a/arch/tile/kernel/entry.S +++ b/arch/tile/kernel/entry.S @@ -27,22 +27,6 @@ STD_ENTRY(current_text_addr) { move r0, lr; jrp lr } STD_ENDPROC(current_text_addr) -/* - * We don't run this function directly, but instead copy it to a page - * we map into every user process. See vdso_setup(). - * - * Note that libc has a copy of this function that it uses to compare - * against the PC when a stack backtrace ends, so if this code is - * changed, the libc implementation(s) should also be updated. - */ - .pushsection .data -ENTRY(__rt_sigreturn) - moveli TREG_SYSCALL_NR_NAME,__NR_rt_sigreturn - swint1 - ENDPROC(__rt_sigreturn) - ENTRY(__rt_sigreturn_end) - .popsection - STD_ENTRY(dump_stack) { move r2, lr; lnk r1 } { move r4, r52; addli r1, r1, dump_stack - . } diff --git a/arch/tile/kernel/signal.c b/arch/tile/kernel/signal.c index 9531845bf661..2d1dbf38a9ab 100644 --- a/arch/tile/kernel/signal.c +++ b/arch/tile/kernel/signal.c @@ -33,6 +33,7 @@ #include <asm/ucontext.h> #include <asm/sigframe.h> #include <asm/syscalls.h> +#include <asm/vdso.h> #include <arch/interrupts.h> #define DEBUG_SIG 0 @@ -190,7 +191,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, if (err) goto give_sigsegv; - restorer = VDSO_BASE; + restorer = VDSO_SYM(&__vdso_rt_sigreturn); if (ka->sa.sa_flags & SA_RESTORER) restorer = (unsigned long) ka->sa.sa_restorer; diff --git a/arch/tile/kernel/stack.c b/arch/tile/kernel/stack.c index 176ffe48eee9..a9db923bb9eb 100644 --- a/arch/tile/kernel/stack.c +++ b/arch/tile/kernel/stack.c @@ -29,6 +29,7 @@ #include <asm/switch_to.h> #include <asm/sigframe.h> #include <asm/stack.h> +#include <asm/vdso.h> #include <arch/abi.h> #include <arch/interrupts.h> @@ -119,7 +120,7 @@ static struct pt_regs *valid_fault_handler(struct KBacktraceIterator* kbt) /* Is the pc pointing to a sigreturn trampoline? */ static int is_sigreturn(unsigned long pc) { - return (pc == VDSO_BASE); + return current->mm && (pc == VDSO_SYM(&__vdso_rt_sigreturn)); } /* Return a pt_regs pointer for a valid signal handler frame */ @@ -128,7 +129,7 @@ static struct pt_regs *valid_sigframe(struct KBacktraceIterator* kbt, { BacktraceIterator *b = &kbt->it; - if (b->pc == VDSO_BASE && b->sp < PAGE_OFFSET && + if (is_sigreturn(b->pc) && b->sp < PAGE_OFFSET && b->sp % sizeof(long) == 0) { int retval; pagefault_disable(); diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c index 5ac397ec6986..36dc1e1bc0a0 100644 --- a/arch/tile/kernel/time.c +++ b/arch/tile/kernel/time.c @@ -23,8 +23,10 @@ #include <linux/smp.h> #include <linux/delay.h> #include <linux/module.h> +#include <linux/timekeeper_internal.h> #include <asm/irq_regs.h> #include <asm/traps.h> +#include <asm/vdso.h> #include <hv/hypervisor.h> #include <arch/interrupts.h> #include <arch/spr_def.h> @@ -110,7 +112,6 @@ void __init time_init(void) setup_tile_timer(); } - /* * Define the tile timer clock event device. The timer is driven by * the TILE_TIMER_CONTROL register, which consists of a 31-bit down @@ -237,3 +238,37 @@ cycles_t ns2cycles(unsigned long nsecs) struct clock_event_device *dev = &__raw_get_cpu_var(tile_timer); return ((u64)nsecs * dev->mult) >> dev->shift; } + +void update_vsyscall_tz(void) +{ + /* Userspace gettimeofday will spin while this value is odd. */ + ++vdso_data->tz_update_count; + smp_wmb(); + vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; + vdso_data->tz_dsttime = sys_tz.tz_dsttime; + smp_wmb(); + ++vdso_data->tz_update_count; +} + +void update_vsyscall(struct timekeeper *tk) +{ + struct timespec wall_time = tk_xtime(tk); + struct timespec *wtm = &tk->wall_to_monotonic; + struct clocksource *clock = tk->clock; + + if (clock != &cycle_counter_cs) + return; + + /* Userspace gettimeofday will spin while this value is odd. */ + ++vdso_data->tb_update_count; + smp_wmb(); + vdso_data->xtime_tod_stamp = clock->cycle_last; + vdso_data->xtime_clock_sec = wall_time.tv_sec; + vdso_data->xtime_clock_nsec = wall_time.tv_nsec; + vdso_data->wtom_clock_sec = wtm->tv_sec; + vdso_data->wtom_clock_nsec = wtm->tv_nsec; + vdso_data->mult = clock->mult; + vdso_data->shift = clock->shift; + smp_wmb(); + ++vdso_data->tb_update_count; +} diff --git a/arch/tile/kernel/vdso.c b/arch/tile/kernel/vdso.c new file mode 100644 index 000000000000..1533af24106e --- /dev/null +++ b/arch/tile/kernel/vdso.c @@ -0,0 +1,212 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/binfmts.h> +#include <linux/compat.h> +#include <linux/elf.h> +#include <linux/mm.h> +#include <linux/pagemap.h> + +#include <asm/vdso.h> +#include <asm/mman.h> +#include <asm/sections.h> + +#include <arch/sim.h> + +/* The alignment of the vDSO. */ +#define VDSO_ALIGNMENT PAGE_SIZE + + +static unsigned int vdso_pages; +static struct page **vdso_pagelist; + +#ifdef CONFIG_COMPAT +static unsigned int vdso32_pages; +static struct page **vdso32_pagelist; +#endif +static int vdso_ready; + +/* + * The vdso data page. + */ +static union { + struct vdso_data data; + u8 page[PAGE_SIZE]; +} vdso_data_store __page_aligned_data; + +struct vdso_data *vdso_data = &vdso_data_store.data; + +static unsigned int __read_mostly vdso_enabled = 1; + +static struct page **vdso_setup(void *vdso_kbase, unsigned int pages) +{ + int i; + struct page **pagelist; + + pagelist = kzalloc(sizeof(struct page *) * (pages + 1), GFP_KERNEL); + BUG_ON(pagelist == NULL); + for (i = 0; i < pages - 1; i++) { + struct page *pg = virt_to_page(vdso_kbase + i*PAGE_SIZE); + ClearPageReserved(pg); + pagelist[i] = pg; + } + pagelist[pages - 1] = virt_to_page(vdso_data); + pagelist[pages] = NULL; + + return pagelist; +} + +static int __init vdso_init(void) +{ + int data_pages = sizeof(vdso_data_store) >> PAGE_SHIFT; + + /* + * We can disable vDSO support generally, but we need to retain + * one page to support the two-bundle (16-byte) rt_sigreturn path. + */ + if (!vdso_enabled) { + size_t offset = (unsigned long)&__vdso_rt_sigreturn; + static struct page *sigret_page; + sigret_page = alloc_page(GFP_KERNEL | __GFP_ZERO); + BUG_ON(sigret_page == NULL); + vdso_pagelist = &sigret_page; + vdso_pages = 1; + BUG_ON(offset >= PAGE_SIZE); + memcpy(page_address(sigret_page) + offset, + vdso_start + offset, 16); +#ifdef CONFIG_COMPAT + vdso32_pages = vdso_pages; + vdso32_pagelist = vdso_pagelist; +#endif + vdso_ready = 1; + return 0; + } + + vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT; + vdso_pages += data_pages; + vdso_pagelist = vdso_setup(vdso_start, vdso_pages); + +#ifdef CONFIG_COMPAT + vdso32_pages = (vdso32_end - vdso32_start) >> PAGE_SHIFT; + vdso32_pages += data_pages; + vdso32_pagelist = vdso_setup(vdso32_start, vdso32_pages); +#endif + + smp_wmb(); + vdso_ready = 1; + + return 0; +} +arch_initcall(vdso_init); + +const char *arch_vma_name(struct vm_area_struct *vma) +{ + if (vma->vm_mm && vma->vm_start == VDSO_BASE) + return "[vdso]"; +#ifndef __tilegx__ + if (vma->vm_start == MEM_USER_INTRPT) + return "[intrpt]"; +#endif + return NULL; +} + +struct vm_area_struct *get_gate_vma(struct mm_struct *mm) +{ + return NULL; +} + +int in_gate_area(struct mm_struct *mm, unsigned long address) +{ + return 0; +} + +int in_gate_area_no_mm(unsigned long address) +{ + return 0; +} + +int setup_vdso_pages(void) +{ + struct page **pagelist; + unsigned long pages; + struct mm_struct *mm = current->mm; + unsigned long vdso_base = 0; + int retval = 0; + + if (!vdso_ready) + return 0; + + mm->context.vdso_base = 0; + + pagelist = vdso_pagelist; + pages = vdso_pages; +#ifdef CONFIG_COMPAT + if (is_compat_task()) { + pagelist = vdso32_pagelist; + pages = vdso32_pages; + } +#endif + + /* + * vDSO has a problem and was disabled, just don't "enable" it for the + * process. + */ + if (pages == 0) + return 0; + + vdso_base = get_unmapped_area(NULL, vdso_base, + (pages << PAGE_SHIFT) + + ((VDSO_ALIGNMENT - 1) & PAGE_MASK), + 0, 0); + if (IS_ERR_VALUE(vdso_base)) { + retval = vdso_base; + return retval; + } + + /* Add required alignment. */ + vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT); + + /* + * Put vDSO base into mm struct. We need to do this before calling + * install_special_mapping or the perf counter mmap tracking code + * will fail to recognise it as a vDSO (since arch_vma_name fails). + */ + mm->context.vdso_base = vdso_base; + + /* + * our vma flags don't have VM_WRITE so by default, the process isn't + * allowed to write those pages. + * gdb can break that with ptrace interface, and thus trigger COW on + * those pages but it's then your responsibility to never do that on + * the "data" page of the vDSO or you'll stop getting kernel updates + * and your nice userland gettimeofday will be totally dead. + * It's fine to use that for setting breakpoints in the vDSO code + * pages though + */ + retval = install_special_mapping(mm, vdso_base, + pages << PAGE_SHIFT, + VM_READ|VM_EXEC | + VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, + pagelist); + if (retval) + mm->context.vdso_base = 0; + + return retval; +} + +static __init int vdso_func(char *s) +{ + return kstrtouint(s, 0, &vdso_enabled); +} +__setup("vdso=", vdso_func); diff --git a/arch/tile/kernel/vdso/Makefile b/arch/tile/kernel/vdso/Makefile new file mode 100644 index 000000000000..e2b7a2f4ee41 --- /dev/null +++ b/arch/tile/kernel/vdso/Makefile @@ -0,0 +1,118 @@ +# Symbols present in the vdso +vdso-syms = rt_sigreturn gettimeofday + +# Files to link into the vdso +obj-vdso = $(patsubst %, v%.o, $(vdso-syms)) + +# Build rules +targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds +obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) + +# vdso32 is only for tilegx -m32 compat task. +VDSO32-$(CONFIG_COMPAT) := y + +obj-y += vdso.o +obj-$(VDSO32-y) += vdso32.o +extra-y += vdso.lds +CPPFLAGS_vdso.lds += -P -C -U$(ARCH) + +# vDSO code runs in userspace and -pg doesn't help with profiling anyway. +CFLAGS_REMOVE_vdso.o = -pg +CFLAGS_REMOVE_vdso32.o = -pg +CFLAGS_REMOVE_vrt_sigreturn.o = -pg +CFLAGS_REMOVE_vrt_sigreturn32.o = -pg +CFLAGS_REMOVE_vgettimeofday.o = -pg +CFLAGS_REMOVE_vgettimeofday32.o = -pg + +ifdef CONFIG_FEEDBACK_COLLECT +# vDSO code runs in userspace, not collecting feedback data. +CFLAGS_REMOVE_vdso.o = -ffeedback-generate +CFLAGS_REMOVE_vdso32.o = -ffeedback-generate +CFLAGS_REMOVE_vrt_sigreturn.o = -ffeedback-generate +CFLAGS_REMOVE_vrt_sigreturn32.o = -ffeedback-generate +CFLAGS_REMOVE_vgettimeofday.o = -ffeedback-generate +CFLAGS_REMOVE_vgettimeofday32.o = -ffeedback-generate +endif + +# Disable gcov profiling for VDSO code +GCOV_PROFILE := n + +# Force dependency +$(obj)/vdso.o: $(obj)/vdso.so + +# link rule for the .so file, .lds has to be first +SYSCFLAGS_vdso.so.dbg = $(c_flags) +$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) + $(call if_changed,vdsold) + + +# We also create a special relocatable object that should mirror the symbol +# table and layout of the linked DSO. With ld -R we can then refer to +# these symbols in the kernel code rather than hand-coded addresses. +extra-y += vdso-syms.o +$(obj)/built-in.o: $(obj)/vdso-syms.o +$(obj)/built-in.o: ld_flags += -R $(obj)/vdso-syms.o + +SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ + $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) +SYSCFLAGS_vdso_syms.o = -r +$(obj)/vdso-syms.o: $(src)/vdso.lds $(obj)/vrt_sigreturn.o FORCE + $(call if_changed,vdsold) + + +# strip rule for the .so file +$(obj)/%.so: OBJCOPYFLAGS := -S +$(obj)/%.so: $(obj)/%.so.dbg FORCE + $(call if_changed,objcopy) + +# actual build commands +# The DSO images are built using a special linker script +# Add -lgcc so tilepro gets static muldi3 and lshrdi3 definitions. +# Make sure only to export the intended __vdso_xxx symbol offsets. +quiet_cmd_vdsold = VDSOLD $@ + cmd_vdsold = $(CC) $(KCFLAGS) -nostdlib $(SYSCFLAGS_$(@F)) \ + -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp -lgcc && \ + $(CROSS_COMPILE)objcopy \ + $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ + +# install commands for the unstripped file +quiet_cmd_vdso_install = INSTALL $@ + cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ + +vdso.so: $(obj)/vdso.so.dbg + @mkdir -p $(MODLIB)/vdso + $(call cmd,vdso_install) + +vdso32.so: $(obj)/vdso32.so.dbg + $(call cmd,vdso_install) + +vdso_install: vdso.so +vdso32_install: vdso32.so + + +KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) +KBUILD_AFLAGS_32 += -m32 -s +KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS)) +KBUILD_CFLAGS_32 += -m32 -fPIC -shared + +obj-vdso32 = $(patsubst %, v%32.o, $(vdso-syms)) +obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32)) + +targets += $(obj-vdso32) vdso32.so vdso32.so.dbg + +$(obj-vdso32:%=%): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32) +$(obj-vdso32:%=%): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32) + +$(obj)/vgettimeofday32.o: $(obj)/vgettimeofday.c + $(call if_changed,cc_o_c) + +$(obj)/vrt_sigreturn32.o: $(obj)/vrt_sigreturn.S + $(call if_changed,as_o_S) + +# Force dependency +$(obj)/vdso32.o: $(obj)/vdso32.so + +SYSCFLAGS_vdso32.so.dbg = -m32 -shared -s -Wl,-soname=linux-vdso32.so.1 \ + $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) +$(obj)/vdso32.so.dbg: $(src)/vdso.lds $(obj-vdso32) + $(call if_changed,vdsold) diff --git a/arch/tile/kernel/vdso/vdso.S b/arch/tile/kernel/vdso/vdso.S new file mode 100644 index 000000000000..3467adb41630 --- /dev/null +++ b/arch/tile/kernel/vdso/vdso.S @@ -0,0 +1,28 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <asm/page.h> + + __PAGE_ALIGNED_DATA + + .global vdso_start, vdso_end + .align PAGE_SIZE +vdso_start: + .incbin "arch/tile/kernel/vdso/vdso.so" + .align PAGE_SIZE +vdso_end: + + .previous diff --git a/arch/tile/kernel/vdso/vdso.lds.S b/arch/tile/kernel/vdso/vdso.lds.S new file mode 100644 index 000000000000..041cd6c39c83 --- /dev/null +++ b/arch/tile/kernel/vdso/vdso.lds.S @@ -0,0 +1,87 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#define VDSO_VERSION_STRING LINUX_2.6 + + +OUTPUT_ARCH(tile) + +/* The ELF entry point can be used to set the AT_SYSINFO value. */ +ENTRY(__vdso_rt_sigreturn); + + +SECTIONS +{ + . = SIZEOF_HEADERS; + + .hash : { *(.hash) } :text + .gnu.hash : { *(.gnu.hash) } + .dynsym : { *(.dynsym) } + .dynstr : { *(.dynstr) } + .gnu.version : { *(.gnu.version) } + .gnu.version_d : { *(.gnu.version_d) } + .gnu.version_r : { *(.gnu.version_r) } + + .note : { *(.note.*) } :text :note + .dynamic : { *(.dynamic) } :text :dynamic + + .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr + .eh_frame : { KEEP (*(.eh_frame)) } :text + + .rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) } + + /* + * This linker script is used both with -r and with -shared. + * For the layouts to match, we need to skip more than enough + * space for the dynamic symbol table et al. If this amount + * is insufficient, ld -shared will barf. Just increase it here. + */ + . = 0x1000; + .text : { *(.text .text.*) } :text + + .data : { + *(.got.plt) *(.got) + *(.data .data.* .gnu.linkonce.d.*) + *(.dynbss) + *(.bss .bss.* .gnu.linkonce.b.*) + } +} + + +/* + * We must supply the ELF program headers explicitly to get just one + * PT_LOAD segment, and set the flags explicitly to make segments read-only. + */ +PHDRS +{ + text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ + dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ + note PT_NOTE FLAGS(4); /* PF_R */ + eh_frame_hdr PT_GNU_EH_FRAME; +} + + +/* + * This controls what userland symbols we export from the vDSO. + */ +VERSION +{ + VDSO_VERSION_STRING { + global: + __vdso_rt_sigreturn; + __vdso_gettimeofday; + gettimeofday; + local:*; + }; +} diff --git a/arch/tile/kernel/vdso/vdso32.S b/arch/tile/kernel/vdso/vdso32.S new file mode 100644 index 000000000000..1d1ac3257e11 --- /dev/null +++ b/arch/tile/kernel/vdso/vdso32.S @@ -0,0 +1,28 @@ +/* + * Copyright 2013 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <asm/page.h> + + __PAGE_ALIGNED_DATA + + .global vdso32_start, vdso32_end + .align PAGE_SIZE +vdso32_start: + .incbin "arch/tile/kernel/vdso/vdso32.so" + .align PAGE_SIZE +vdso32_end: + + .previous diff --git a/arch/tile/kernel/vdso/vgettimeofday.c b/arch/tile/kernel/vdso/vgettimeofday.c new file mode 100644 index 000000000000..51ec8e46f5f9 --- /dev/null +++ b/arch/tile/kernel/vdso/vgettimeofday.c @@ -0,0 +1,107 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#define VDSO_BUILD /* avoid some shift warnings for -m32 in <asm/page.h> */ +#include <linux/time.h> +#include <asm/timex.h> +#include <asm/vdso.h> + +#if CHIP_HAS_SPLIT_CYCLE() +static inline cycles_t get_cycles_inline(void) +{ + unsigned int high = __insn_mfspr(SPR_CYCLE_HIGH); + unsigned int low = __insn_mfspr(SPR_CYCLE_LOW); + unsigned int high2 = __insn_mfspr(SPR_CYCLE_HIGH); + + while (unlikely(high != high2)) { + low = __insn_mfspr(SPR_CYCLE_LOW); + high = high2; + high2 = __insn_mfspr(SPR_CYCLE_HIGH); + } + + return (((cycles_t)high) << 32) | low; +} +#define get_cycles get_cycles_inline +#endif + +/* + * Find out the vDSO data page address in the process address space. + */ +inline unsigned long get_datapage(void) +{ + unsigned long ret; + + /* vdso data page located in the 2nd vDSO page. */ + asm volatile ("lnk %0" : "=r"(ret)); + ret &= ~(PAGE_SIZE - 1); + ret += PAGE_SIZE; + + return ret; +} + +int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) +{ + cycles_t cycles; + unsigned long count, sec, ns; + volatile struct vdso_data *vdso_data; + + vdso_data = (struct vdso_data *)get_datapage(); + /* The use of the timezone is obsolete, normally tz is NULL. */ + if (unlikely(tz != NULL)) { + while (1) { + /* Spin until the update finish. */ + count = vdso_data->tz_update_count; + if (count & 1) + continue; + + tz->tz_minuteswest = vdso_data->tz_minuteswest; + tz->tz_dsttime = vdso_data->tz_dsttime; + + /* Check whether updated, read again if so. */ + if (count == vdso_data->tz_update_count) + break; + } + } + + if (unlikely(tv == NULL)) + return 0; + + while (1) { + /* Spin until the update finish. */ + count = vdso_data->tb_update_count; + if (count & 1) + continue; + + cycles = (get_cycles() - vdso_data->xtime_tod_stamp); + ns = (cycles * vdso_data->mult) >> vdso_data->shift; + sec = vdso_data->xtime_clock_sec; + ns += vdso_data->xtime_clock_nsec; + if (ns >= NSEC_PER_SEC) { + ns -= NSEC_PER_SEC; + sec += 1; + } + + /* Check whether updated, read again if so. */ + if (count == vdso_data->tb_update_count) + break; + } + + tv->tv_sec = sec; + tv->tv_usec = ns / 1000; + + return 0; +} + +int gettimeofday(struct timeval *tv, struct timezone *tz) + __attribute__((weak, alias("__vdso_gettimeofday"))); diff --git a/arch/tile/kernel/vdso/vrt_sigreturn.S b/arch/tile/kernel/vdso/vrt_sigreturn.S new file mode 100644 index 000000000000..6326caf4a039 --- /dev/null +++ b/arch/tile/kernel/vdso/vrt_sigreturn.S @@ -0,0 +1,30 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/linkage.h> +#include <arch/abi.h> +#include <asm/unistd.h> + +/* + * Note that libc has a copy of this function that it uses to compare + * against the PC when a stack backtrace ends, so if this code is + * changed, the libc implementation(s) should also be updated. + */ +ENTRY(__vdso_rt_sigreturn) + moveli TREG_SYSCALL_NR_NAME, __NR_rt_sigreturn + swint1 + /* We don't use ENDPROC to avoid tagging this symbol as FUNC, + * which confuses the perf tool. + */ + END(__vdso_rt_sigreturn) diff --git a/arch/tile/mm/elf.c b/arch/tile/mm/elf.c index 1691b81b2b0c..23f044e8a7ab 100644 --- a/arch/tile/mm/elf.c +++ b/arch/tile/mm/elf.c @@ -21,6 +21,7 @@ #include <asm/pgtable.h> #include <asm/pgalloc.h> #include <asm/sections.h> +#include <asm/vdso.h> #include <arch/sim.h> /* Notify a running simulator, if any, that an exec just occurred. */ @@ -102,37 +103,10 @@ static void sim_notify_interp(unsigned long load_addr) } -/* Kernel address of page used to map read-only kernel data into userspace. */ -static void *vdso_page; - -/* One-entry array used for install_special_mapping. */ -static struct page *vdso_pages[1]; - -static int __init vdso_setup(void) -{ - vdso_page = (void *)get_zeroed_page(GFP_ATOMIC); - memcpy(vdso_page, __rt_sigreturn, __rt_sigreturn_end - __rt_sigreturn); - vdso_pages[0] = virt_to_page(vdso_page); - return 0; -} -device_initcall(vdso_setup); - -const char *arch_vma_name(struct vm_area_struct *vma) -{ - if (vma->vm_private_data == vdso_pages) - return "[vdso]"; -#ifndef __tilegx__ - if (vma->vm_start == MEM_USER_INTRPT) - return "[intrpt]"; -#endif - return NULL; -} - int arch_setup_additional_pages(struct linux_binprm *bprm, int executable_stack) { struct mm_struct *mm = current->mm; - unsigned long vdso_base; int retval = 0; down_write(&mm->mmap_sem); @@ -145,14 +119,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, if (!notify_exec(mm)) sim_notify_exec(bprm->filename); - /* - * MAYWRITE to allow gdb to COW and set breakpoints - */ - vdso_base = VDSO_BASE; - retval = install_special_mapping(mm, vdso_base, PAGE_SIZE, - VM_READ|VM_EXEC| - VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, - vdso_pages); + retval = setup_vdso_pages(); #ifndef __tilegx__ /* |