From b32e41bb97971161ad34ea69364c4f9ec3909151 Mon Sep 17 00:00:00 2001 From: Milind Arun Choudhary Date: Tue, 8 May 2007 00:30:08 -0700 Subject: SPIN_LOCK_UNLOCKED cleanup in init_task.h SPIN_LOCK_UNLOCKED cleanup,use __SPIN_LOCK_UNLOCKED instead Signed-off-by: Milind Arun Choudhary Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/init_task.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/init_task.h') diff --git a/include/linux/init_task.h b/include/linux/init_task.h index a2d95ff50e9b..795102309bf1 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -138,7 +138,7 @@ extern struct group_info init_groups; .journal_info = NULL, \ .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ .fs_excl = ATOMIC_INIT(0), \ - .pi_lock = SPIN_LOCK_UNLOCKED, \ + .pi_lock = __SPIN_LOCK_UNLOCKED(tsk.pi_lock), \ INIT_TRACE_IRQFLAGS \ INIT_LOCKDEP \ } -- cgit v1.2.3 From f7e4217b007d1f73e7e3cf10ba4fea4a608c603f Mon Sep 17 00:00:00 2001 From: Roman Zippel Date: Wed, 9 May 2007 02:35:17 -0700 Subject: rename thread_info to stack This finally renames the thread_info field in task structure to stack, so that the assumptions about this field are gone and archs have more freedom about placing the thread_info structure. Nonbroken archs which have a proper thread pointer can do the access to both current thread and task structure via a single pointer. It'll allow for a few more cleanups of the fork code, from which e.g. ia64 could benefit. Signed-off-by: Roman Zippel [akpm@linux-foundation.org: build fix] Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Russell King Cc: Ian Molton Cc: Haavard Skinnemoen Cc: Mikael Starvik Cc: David Howells Cc: Yoshinori Sato Cc: "Luck, Tony" Cc: Hirokazu Takata Cc: Geert Uytterhoeven Cc: Roman Zippel Cc: Greg Ungerer Cc: Ralf Baechle Cc: Ralf Baechle Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Heiko Carstens Cc: Martin Schwidefsky Cc: Paul Mundt Cc: Kazumoto Kojima Cc: Richard Curnow Cc: William Lee Irwin III Cc: "David S. Miller" Cc: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Cc: Miles Bader Cc: Andi Kleen Cc: Chris Zankel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/blackfin/kernel/ptrace.c | 6 +++--- arch/h8300/kernel/asm-offsets.c | 2 +- arch/ia64/kernel/mca.c | 2 +- arch/mips/kernel/asm-offsets.c | 2 +- arch/parisc/kernel/asm-offsets.c | 2 +- arch/powerpc/kernel/asm-offsets.c | 2 +- arch/ppc/kernel/asm-offsets.c | 2 +- arch/s390/kernel/asm-offsets.c | 2 +- arch/sparc/kernel/asm-offsets.c | 2 +- arch/v850/kernel/asm-offsets.c | 2 +- arch/xtensa/kernel/asm-offsets.c | 2 +- include/asm-alpha/thread_info.h | 8 ++++---- include/asm-blackfin/processor.h | 6 +++--- include/asm-blackfin/system.h | 4 ++-- include/asm-m68k/thread_info.h | 6 +++--- include/asm-x86_64/system.h | 2 +- include/linux/init_task.h | 2 +- include/linux/sched.h | 8 ++++---- kernel/fork.c | 4 ++-- 19 files changed, 33 insertions(+), 33 deletions(-) (limited to 'include/linux/init_task.h') diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c index d7c8e514cb92..e718bb4a1ef0 100644 --- a/arch/blackfin/kernel/ptrace.c +++ b/arch/blackfin/kernel/ptrace.c @@ -73,7 +73,7 @@ static inline struct pt_regs *get_user_regs(struct task_struct *task) { return (struct pt_regs *) - ((unsigned long)task->thread_info + + ((unsigned long)task_stack_page(task) + (THREAD_SIZE - sizeof(struct pt_regs))); } @@ -99,7 +99,7 @@ static inline long get_reg(struct task_struct *task, int regno) unsigned char *reg_ptr; struct pt_regs *regs = - (struct pt_regs *)((unsigned long)task->thread_info + + (struct pt_regs *)((unsigned long)task_stack_page(task) + (THREAD_SIZE - sizeof(struct pt_regs))); reg_ptr = (char *)regs; @@ -125,7 +125,7 @@ put_reg(struct task_struct *task, int regno, unsigned long data) char * reg_ptr; struct pt_regs *regs = - (struct pt_regs *)((unsigned long)task->thread_info + + (struct pt_regs *)((unsigned long)task_stack_page(task) + (THREAD_SIZE - sizeof(struct pt_regs))); reg_ptr = (char *)regs; diff --git a/arch/h8300/kernel/asm-offsets.c b/arch/h8300/kernel/asm-offsets.c index b78b82ad28a3..fc30b4fd0914 100644 --- a/arch/h8300/kernel/asm-offsets.c +++ b/arch/h8300/kernel/asm-offsets.c @@ -30,7 +30,7 @@ int main(void) DEFINE(TASK_PTRACE, offsetof(struct task_struct, ptrace)); DEFINE(TASK_BLOCKED, offsetof(struct task_struct, blocked)); DEFINE(TASK_THREAD, offsetof(struct task_struct, thread)); - DEFINE(TASK_THREAD_INFO, offsetof(struct task_struct, thread_info)); + DEFINE(TASK_THREAD_INFO, offsetof(struct task_struct, stack)); DEFINE(TASK_MM, offsetof(struct task_struct, mm)); DEFINE(TASK_ACTIVE_MM, offsetof(struct task_struct, active_mm)); diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c index 1d7cc7e2ce32..f8ae709de0b5 100644 --- a/arch/ia64/kernel/mca.c +++ b/arch/ia64/kernel/mca.c @@ -1689,7 +1689,7 @@ format_mca_init_stack(void *mca_data, unsigned long offset, ti->preempt_count = 1; ti->task = p; ti->cpu = cpu; - p->thread_info = ti; + p->stack = ti; p->state = TASK_UNINTERRUPTIBLE; cpu_set(cpu, p->cpus_allowed); INIT_LIST_HEAD(&p->tasks); diff --git a/arch/mips/kernel/asm-offsets.c b/arch/mips/kernel/asm-offsets.c index 761a779d5c4f..3b27309d54b1 100644 --- a/arch/mips/kernel/asm-offsets.c +++ b/arch/mips/kernel/asm-offsets.c @@ -82,7 +82,7 @@ void output_task_defines(void) { text("/* MIPS task_struct offsets. */"); offset("#define TASK_STATE ", struct task_struct, state); - offset("#define TASK_THREAD_INFO ", struct task_struct, thread_info); + offset("#define TASK_THREAD_INFO ", struct task_struct, stack); offset("#define TASK_FLAGS ", struct task_struct, flags); offset("#define TASK_MM ", struct task_struct, mm); offset("#define TASK_PID ", struct task_struct, pid); diff --git a/arch/parisc/kernel/asm-offsets.c b/arch/parisc/kernel/asm-offsets.c index 54fdb959149c..d3b7917a87cb 100644 --- a/arch/parisc/kernel/asm-offsets.c +++ b/arch/parisc/kernel/asm-offsets.c @@ -54,7 +54,7 @@ int main(void) { - DEFINE(TASK_THREAD_INFO, offsetof(struct task_struct, thread_info)); + DEFINE(TASK_THREAD_INFO, offsetof(struct task_struct, stack)); DEFINE(TASK_STATE, offsetof(struct task_struct, state)); DEFINE(TASK_FLAGS, offsetof(struct task_struct, flags)); DEFINE(TASK_SIGPENDING, offsetof(struct task_struct, pending)); diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 8f48560b7ee2..37bc35e69dbe 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -58,7 +58,7 @@ int main(void) #ifdef CONFIG_PPC64 DEFINE(AUDITCONTEXT, offsetof(struct task_struct, audit_context)); #else - DEFINE(THREAD_INFO, offsetof(struct task_struct, thread_info)); + DEFINE(THREAD_INFO, offsetof(struct task_struct, stack)); DEFINE(PTRACE, offsetof(struct task_struct, ptrace)); #endif /* CONFIG_PPC64 */ diff --git a/arch/ppc/kernel/asm-offsets.c b/arch/ppc/kernel/asm-offsets.c index c5850a272650..e8e94321b59e 100644 --- a/arch/ppc/kernel/asm-offsets.c +++ b/arch/ppc/kernel/asm-offsets.c @@ -35,7 +35,7 @@ int main(void) { DEFINE(THREAD, offsetof(struct task_struct, thread)); - DEFINE(THREAD_INFO, offsetof(struct task_struct, thread_info)); + DEFINE(THREAD_INFO, offsetof(struct task_struct, stack)); DEFINE(MM, offsetof(struct task_struct, mm)); DEFINE(PTRACE, offsetof(struct task_struct, ptrace)); DEFINE(KSP, offsetof(struct thread_struct, ksp)); diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index ec514fe5ccd0..1375f8a4469e 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -15,7 +15,7 @@ int main(void) { - DEFINE(__THREAD_info, offsetof(struct task_struct, thread_info),); + DEFINE(__THREAD_info, offsetof(struct task_struct, stack),); DEFINE(__THREAD_ksp, offsetof(struct task_struct, thread.ksp),); DEFINE(__THREAD_per, offsetof(struct task_struct, thread.per_info),); DEFINE(__THREAD_mm_segment, diff --git a/arch/sparc/kernel/asm-offsets.c b/arch/sparc/kernel/asm-offsets.c index 29d7cfd1c970..6773ed76e414 100644 --- a/arch/sparc/kernel/asm-offsets.c +++ b/arch/sparc/kernel/asm-offsets.c @@ -28,7 +28,7 @@ int foo(void) DEFINE(AOFF_task_gid, offsetof(struct task_struct, gid)); DEFINE(AOFF_task_euid, offsetof(struct task_struct, euid)); DEFINE(AOFF_task_egid, offsetof(struct task_struct, egid)); - /* DEFINE(THREAD_INFO, offsetof(struct task_struct, thread_info)); */ + /* DEFINE(THREAD_INFO, offsetof(struct task_struct, stack)); */ DEFINE(ASIZ_task_uid, sizeof(current->uid)); DEFINE(ASIZ_task_gid, sizeof(current->gid)); DEFINE(ASIZ_task_euid, sizeof(current->euid)); diff --git a/arch/v850/kernel/asm-offsets.c b/arch/v850/kernel/asm-offsets.c index 24f291369070..cee5c3142d41 100644 --- a/arch/v850/kernel/asm-offsets.c +++ b/arch/v850/kernel/asm-offsets.c @@ -29,7 +29,7 @@ int main (void) DEFINE (TASK_PTRACE, offsetof (struct task_struct, ptrace)); DEFINE (TASK_BLOCKED, offsetof (struct task_struct, blocked)); DEFINE (TASK_THREAD, offsetof (struct task_struct, thread)); - DEFINE (TASK_THREAD_INFO, offsetof (struct task_struct, thread_info)); + DEFINE (TASK_THREAD_INFO, offsetof (struct task_struct, stack)); DEFINE (TASK_MM, offsetof (struct task_struct, mm)); DEFINE (TASK_ACTIVE_MM, offsetof (struct task_struct, active_mm)); DEFINE (TASK_PID, offsetof (struct task_struct, pid)); diff --git a/arch/xtensa/kernel/asm-offsets.c b/arch/xtensa/kernel/asm-offsets.c index b256cfbef344..698079b3a336 100644 --- a/arch/xtensa/kernel/asm-offsets.c +++ b/arch/xtensa/kernel/asm-offsets.c @@ -70,7 +70,7 @@ int main(void) DEFINE(TASK_ACTIVE_MM, offsetof (struct task_struct, active_mm)); DEFINE(TASK_PID, offsetof (struct task_struct, pid)); DEFINE(TASK_THREAD, offsetof (struct task_struct, thread)); - DEFINE(TASK_THREAD_INFO, offsetof (struct task_struct, thread_info)); + DEFINE(TASK_THREAD_INFO, offsetof (struct task_struct, stack)); DEFINE(TASK_STRUCT_SIZE, sizeof (struct task_struct)); BLANK(); diff --git a/include/asm-alpha/thread_info.h b/include/asm-alpha/thread_info.h index eeb3bef91e11..f4defc2bd3fb 100644 --- a/include/asm-alpha/thread_info.h +++ b/include/asm-alpha/thread_info.h @@ -97,7 +97,7 @@ register struct thread_info *__current_thread_info __asm__("$8"); 1 << TIF_UAC_SIGBUS) #define SET_UNALIGN_CTL(task,value) ({ \ - (task)->thread_info->flags = (((task)->thread_info->flags & \ + task_thread_info(task)->flags = ((task_thread_info(task)->flags & \ ~ALPHA_UAC_MASK) \ | (((value) << ALPHA_UAC_SHIFT) & (1<thread_info->flags & (1 << TIF_UAC_NOPRINT)) \ + put_user((task_thread_info(task)->flags & (1 << TIF_UAC_NOPRINT))\ >> ALPHA_UAC_SHIFT \ - | ((task)->thread_info->flags & (1 << TIF_UAC_SIGBUS)) \ + | (task_thread_info(task)->flags & (1 << TIF_UAC_SIGBUS))\ >> (ALPHA_UAC_SHIFT + 1) \ - | ((task)->thread_info->flags & (1 << TIF_UAC_NOFIX)) \ + | (task_thread_info(task)->flags & (1 << TIF_UAC_NOFIX))\ >> (ALPHA_UAC_SHIFT - 1), \ (int __user *)(value)); \ }) diff --git a/include/asm-blackfin/processor.h b/include/asm-blackfin/processor.h index 997465c93e82..0336ff132c16 100644 --- a/include/asm-blackfin/processor.h +++ b/include/asm-blackfin/processor.h @@ -58,10 +58,10 @@ do { \ (_regs)->pc = (_pc); \ if (current->mm) \ (_regs)->p5 = current->mm->start_data; \ - current->thread_info->l1_task_info.stack_start \ + task_thread_info(current)->l1_task_info.stack_start \ = (void *)current->mm->context.stack_start; \ - current->thread_info->l1_task_info.lowest_sp = (void *)(_usp); \ - memcpy(L1_SCRATCH_TASK_INFO, ¤t->thread_info->l1_task_info, \ + task_thread_info(current)->l1_task_info.lowest_sp = (void *)(_usp); \ + memcpy(L1_SCRATCH_TASK_INFO, &task_thread_info(current)->l1_task_info, \ sizeof(*L1_SCRATCH_TASK_INFO)); \ wrusp(_usp); \ } while(0) diff --git a/include/asm-blackfin/system.h b/include/asm-blackfin/system.h index b5bf6e7cb5e8..5e5f1a0566c0 100644 --- a/include/asm-blackfin/system.h +++ b/include/asm-blackfin/system.h @@ -239,9 +239,9 @@ asmlinkage struct task_struct *resume(struct task_struct *prev, struct task_stru #define switch_to(prev,next,last) \ do { \ - memcpy (&prev->thread_info->l1_task_info, L1_SCRATCH_TASK_INFO, \ + memcpy (&task_thread_info(prev)->l1_task_info, L1_SCRATCH_TASK_INFO, \ sizeof *L1_SCRATCH_TASK_INFO); \ - memcpy (L1_SCRATCH_TASK_INFO, &next->thread_info->l1_task_info, \ + memcpy (L1_SCRATCH_TASK_INFO, &task_thread_info(next)->l1_task_info, \ sizeof *L1_SCRATCH_TASK_INFO); \ (last) = resume (prev, next); \ } while (0) diff --git a/include/asm-m68k/thread_info.h b/include/asm-m68k/thread_info.h index c4d622a57dfb..d635a3752488 100644 --- a/include/asm-m68k/thread_info.h +++ b/include/asm-m68k/thread_info.h @@ -37,17 +37,17 @@ struct thread_info { #define init_stack (init_thread_union.stack) #define task_thread_info(tsk) (&(tsk)->thread.info) -#define task_stack_page(tsk) ((void *)(tsk)->thread_info) +#define task_stack_page(tsk) ((tsk)->stack) #define current_thread_info() task_thread_info(current) #define __HAVE_THREAD_FUNCTIONS #define setup_thread_stack(p, org) ({ \ - *(struct task_struct **)(p)->thread_info = (p); \ + *(struct task_struct **)(p)->stack = (p); \ task_thread_info(p)->task = (p); \ }) -#define end_of_stack(p) ((unsigned long *)(p)->thread_info + 1) +#define end_of_stack(p) ((unsigned long *)(p)->stack + 1) /* entry.S relies on these definitions! * bits 0-7 are tested at every exception exit diff --git a/include/asm-x86_64/system.h b/include/asm-x86_64/system.h index b7b8021e8c43..ead9f9a56234 100644 --- a/include/asm-x86_64/system.h +++ b/include/asm-x86_64/system.h @@ -39,7 +39,7 @@ [threadrsp] "i" (offsetof(struct task_struct, thread.rsp)), \ [ti_flags] "i" (offsetof(struct thread_info, flags)),\ [tif_fork] "i" (TIF_FORK), \ - [thread_info] "i" (offsetof(struct task_struct, thread_info)), \ + [thread_info] "i" (offsetof(struct task_struct, stack)), \ [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent)) \ : "memory", "cc" __EXTRA_CLOBBER) diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 795102309bf1..45170b2fa253 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -95,7 +95,7 @@ extern struct group_info init_groups; #define INIT_TASK(tsk) \ { \ .state = 0, \ - .thread_info = &init_thread_info, \ + .stack = &init_thread_info, \ .usage = ATOMIC_INIT(2), \ .flags = 0, \ .lock_depth = -1, \ diff --git a/include/linux/sched.h b/include/linux/sched.h index 28000b1658f9..17b72d88c4cb 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -817,7 +817,7 @@ struct prio_array; struct task_struct { volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ - struct thread_info *thread_info; + void *stack; atomic_t usage; unsigned int flags; /* per process flags, defined below */ unsigned int ptrace; @@ -1513,8 +1513,8 @@ static inline void unlock_task_sighand(struct task_struct *tsk, #ifndef __HAVE_THREAD_FUNCTIONS -#define task_thread_info(task) (task)->thread_info -#define task_stack_page(task) ((void*)((task)->thread_info)) +#define task_thread_info(task) ((struct thread_info *)(task)->stack) +#define task_stack_page(task) ((task)->stack) static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) { @@ -1524,7 +1524,7 @@ static inline void setup_thread_stack(struct task_struct *p, struct task_struct static inline unsigned long *end_of_stack(struct task_struct *p) { - return (unsigned long *)(p->thread_info + 1); + return (unsigned long *)(task_thread_info(p) + 1); } #endif diff --git a/kernel/fork.c b/kernel/fork.c index a8dd75d4992b..5dd3979747f5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -105,7 +105,7 @@ static struct kmem_cache *mm_cachep; void free_task(struct task_struct *tsk) { - free_thread_info(tsk->thread_info); + free_thread_info(tsk->stack); rt_mutex_debug_task_free(tsk); free_task_struct(tsk); } @@ -175,7 +175,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig) } *tsk = *orig; - tsk->thread_info = ti; + tsk->stack = ti; setup_thread_stack(tsk, orig); #ifdef CONFIG_CC_STACKPROTECTOR -- cgit v1.2.3 From 820e45db2380eb1545fa2bc5d34b8b2f2933faeb Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Thu, 10 May 2007 22:23:00 -0700 Subject: statically initialize struct pid for swapper Statically initialize a struct pid for the swapper process (pid_t == 0) and attach it to init_task. This is needed so task_pid(), task_pgrp() and task_session() interfaces work on the swapper process also. Signed-off-by: Sukadev Bhattiprolu Cc: Cedric Le Goater Cc: Dave Hansen Cc: Serge Hallyn Cc: Eric Biederman Cc: Herbert Poetzl Cc: Acked-by: Eric W. Biederman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/init_task.h | 27 +++++++++++++++++++++++++++ include/linux/pid.h | 2 ++ kernel/pid.c | 2 ++ 3 files changed, 31 insertions(+) (limited to 'include/linux/init_task.h') diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 45170b2fa253..a68835fc8c04 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -88,6 +88,28 @@ extern struct nsproxy init_nsproxy; extern struct group_info init_groups; +#define INIT_STRUCT_PID { \ + .count = ATOMIC_INIT(1), \ + .nr = 0, \ + /* Don't put this struct pid in pid_hash */ \ + .pid_chain = { .next = NULL, .pprev = NULL }, \ + .tasks = { \ + { .first = &init_task.pids[PIDTYPE_PID].node }, \ + { .first = &init_task.pids[PIDTYPE_PGID].node }, \ + { .first = &init_task.pids[PIDTYPE_SID].node }, \ + }, \ + .rcu = RCU_HEAD_INIT, \ +} + +#define INIT_PID_LINK(type) \ +{ \ + .node = { \ + .next = NULL, \ + .pprev = &init_struct_pid.tasks[type].first, \ + }, \ + .pid = &init_struct_pid, \ +} + /* * INIT_TASK is used to set up the first task table, touch at * your own risk!. Base=0, limit=0x1fffff (=2MB) @@ -139,6 +161,11 @@ extern struct group_info init_groups; .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ .fs_excl = ATOMIC_INIT(0), \ .pi_lock = __SPIN_LOCK_UNLOCKED(tsk.pi_lock), \ + .pids = { \ + [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \ + [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \ + [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \ + }, \ INIT_TRACE_IRQFLAGS \ INIT_LOCKDEP \ } diff --git a/include/linux/pid.h b/include/linux/pid.h index 33d343880d89..1e0e4e3423a6 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -51,6 +51,8 @@ struct pid struct rcu_head rcu; }; +extern struct pid init_struct_pid; + struct pid_link { struct hlist_node node; diff --git a/kernel/pid.c b/kernel/pid.c index d76f59326bd4..eb66bd2953ab 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -27,11 +27,13 @@ #include #include #include +#include #define pid_hashfn(nr) hash_long((unsigned long)nr, pidhash_shift) static struct hlist_head *pid_hash; static int pidhash_shift; static struct kmem_cache *pid_cachep; +struct pid init_struct_pid = INIT_STRUCT_PID; int pid_max = PID_MAX_DEFAULT; -- cgit v1.2.3 From 325aa33da784e5997c756a151bc46e9cc9b79db2 Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Thu, 10 May 2007 22:23:10 -0700 Subject: Don't init pgrp and __session in INIT_SIGNALS Remove initialization of pgrp and __session in INIT_SIGNALS, as these are later set by the call to __set_special_pids() in init/main.c by the patch: explicitly-set-pgid-and-sid-of-init-process.patch Signed-off-by: Sukadev Bhattiprolu Cc: Cedric Le Goater Cc: Dave Hansen Cc: Serge Hallyn Cc: Eric Biederman Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/init_task.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/init_task.h') diff --git a/include/linux/init_task.h b/include/linux/init_task.h index a68835fc8c04..66e2f0a70814 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -65,9 +65,9 @@ .posix_timers = LIST_HEAD_INIT(sig.posix_timers), \ .cpu_timers = INIT_CPU_TIMERS(sig.cpu_timers), \ .rlim = INIT_RLIMITS, \ - .pgrp = 1, \ + .pgrp = 0, \ .tty_old_pgrp = NULL, \ - { .__session = 1}, \ + { .__session = 0}, \ } extern struct nsproxy init_nsproxy; -- cgit v1.2.3 From fba2afaaec790dc5ab4ae8827972f342211bbb86 Mon Sep 17 00:00:00 2001 From: Davide Libenzi Date: Thu, 10 May 2007 22:23:13 -0700 Subject: signal/timer/event: signalfd core This patch series implements the new signalfd() system call. I took part of the original Linus code (and you know how badly it can be broken :), and I added even more breakage ;) Signals are fetched from the same signal queue used by the process, so signalfd will compete with standard kernel delivery in dequeue_signal(). If you want to reliably fetch signals on the signalfd file, you need to block them with sigprocmask(SIG_BLOCK). This seems to be working fine on my Dual Opteron machine. I made a quick test program for it: http://www.xmailserver.org/signafd-test.c The signalfd() system call implements signal delivery into a file descriptor receiver. The signalfd file descriptor if created with the following API: int signalfd(int ufd, const sigset_t *mask, size_t masksize); The "ufd" parameter allows to change an existing signalfd sigmask, w/out going to close/create cycle (Linus idea). Use "ufd" == -1 if you want a brand new signalfd file. The "mask" allows to specify the signal mask of signals that we are interested in. The "masksize" parameter is the size of "mask". The signalfd fd supports the poll(2) and read(2) system calls. The poll(2) will return POLLIN when signals are available to be dequeued. As a direct consequence of supporting the Linux poll subsystem, the signalfd fd can use used together with epoll(2) too. The read(2) system call will return a "struct signalfd_siginfo" structure in the userspace supplied buffer. The return value is the number of bytes copied in the supplied buffer, or -1 in case of error. The read(2) call can also return 0, in case the sighand structure to which the signalfd was attached, has been orphaned. The O_NONBLOCK flag is also supported, and read(2) will return -EAGAIN in case no signal is available. If the size of the buffer passed to read(2) is lower than sizeof(struct signalfd_siginfo), -EINVAL is returned. A read from the signalfd can also return -ERESTARTSYS in case a signal hits the process. The format of the struct signalfd_siginfo is, and the valid fields depends of the (->code & __SI_MASK) value, in the same way a struct siginfo would: struct signalfd_siginfo { __u32 signo; /* si_signo */ __s32 err; /* si_errno */ __s32 code; /* si_code */ __u32 pid; /* si_pid */ __u32 uid; /* si_uid */ __s32 fd; /* si_fd */ __u32 tid; /* si_fd */ __u32 band; /* si_band */ __u32 overrun; /* si_overrun */ __u32 trapno; /* si_trapno */ __s32 status; /* si_status */ __s32 svint; /* si_int */ __u64 svptr; /* si_ptr */ __u64 utime; /* si_utime */ __u64 stime; /* si_stime */ __u64 addr; /* si_addr */ }; [akpm@linux-foundation.org: fix signalfd_copyinfo() on i386] Signed-off-by: Davide Libenzi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/Makefile | 1 + fs/exec.c | 11 +- fs/signalfd.c | 349 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/Kbuild | 1 + include/linux/init_task.h | 1 + include/linux/sched.h | 1 + include/linux/signal.h | 1 + include/linux/signalfd.h | 97 +++++++++++++ include/linux/syscalls.h | 1 + init/Kconfig | 10 ++ kernel/exit.c | 9 ++ kernel/fork.c | 8 +- kernel/signal.c | 22 ++- kernel/sys_ni.c | 3 + 14 files changed, 508 insertions(+), 7 deletions(-) create mode 100644 fs/signalfd.c create mode 100644 include/linux/signalfd.h (limited to 'include/linux/init_task.h') diff --git a/fs/Makefile b/fs/Makefile index b5cd46a88cb0..cd8a57aeac04 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_INOTIFY) += inotify.o obj-$(CONFIG_INOTIFY_USER) += inotify_user.o obj-$(CONFIG_EPOLL) += eventpoll.o obj-$(CONFIG_ANON_INODES) += anon_inodes.o +obj-$(CONFIG_SIGNALFD) += signalfd.o obj-$(CONFIG_COMPAT) += compat.o compat_ioctl.o nfsd-$(CONFIG_NFSD) := nfsctl.o diff --git a/fs/exec.c b/fs/exec.c index 2255dc72deef..955a8eb66d70 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -50,6 +50,7 @@ #include #include #include +#include #include #include @@ -581,6 +582,13 @@ static int de_thread(struct task_struct *tsk) struct task_struct *leader = NULL; int count; + /* + * Tell all the sighand listeners that this sighand has + * been detached. The signalfd_detach() function grabs the + * sighand lock, if signal listeners are present on the sighand. + */ + signalfd_detach(tsk); + /* * If we don't share sighandlers, then we aren't sharing anything * and we can just re-use it all. @@ -757,8 +765,7 @@ no_thread_group: spin_unlock(&oldsighand->siglock); write_unlock_irq(&tasklist_lock); - if (atomic_dec_and_test(&oldsighand->count)) - kmem_cache_free(sighand_cachep, oldsighand); + __cleanup_sighand(oldsighand); } BUG_ON(!thread_group_leader(tsk)); diff --git a/fs/signalfd.c b/fs/signalfd.c new file mode 100644 index 000000000000..7cfeab412b45 --- /dev/null +++ b/fs/signalfd.c @@ -0,0 +1,349 @@ +/* + * fs/signalfd.c + * + * Copyright (C) 2003 Linus Torvalds + * + * Mon Mar 5, 2007: Davide Libenzi + * Changed ->read() to return a siginfo strcture instead of signal number. + * Fixed locking in ->poll(). + * Added sighand-detach notification. + * Added fd re-use in sys_signalfd() syscall. + * Now using anonymous inode source. + * Thanks to Oleg Nesterov for useful code review and suggestions. + * More comments and suggestions from Arnd Bergmann. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct signalfd_ctx { + struct list_head lnk; + wait_queue_head_t wqh; + sigset_t sigmask; + struct task_struct *tsk; +}; + +struct signalfd_lockctx { + struct task_struct *tsk; + unsigned long flags; +}; + +/* + * Tries to acquire the sighand lock. We do not increment the sighand + * use count, and we do not even pin the task struct, so we need to + * do it inside an RCU read lock, and we must be prepared for the + * ctx->tsk going to NULL (in signalfd_deliver()), and for the sighand + * being detached. We return 0 if the sighand has been detached, or + * 1 if we were able to pin the sighand lock. + */ +static int signalfd_lock(struct signalfd_ctx *ctx, struct signalfd_lockctx *lk) +{ + struct sighand_struct *sighand = NULL; + + rcu_read_lock(); + lk->tsk = rcu_dereference(ctx->tsk); + if (likely(lk->tsk != NULL)) + sighand = lock_task_sighand(lk->tsk, &lk->flags); + rcu_read_unlock(); + + if (sighand && !ctx->tsk) { + unlock_task_sighand(lk->tsk, &lk->flags); + sighand = NULL; + } + + return sighand != NULL; +} + +static void signalfd_unlock(struct signalfd_lockctx *lk) +{ + unlock_task_sighand(lk->tsk, &lk->flags); +} + +/* + * This must be called with the sighand lock held. + */ +void signalfd_deliver(struct task_struct *tsk, int sig) +{ + struct sighand_struct *sighand = tsk->sighand; + struct signalfd_ctx *ctx, *tmp; + + BUG_ON(!sig); + list_for_each_entry_safe(ctx, tmp, &sighand->signalfd_list, lnk) { + /* + * We use a negative signal value as a way to broadcast that the + * sighand has been orphaned, so that we can notify all the + * listeners about this. Remember the ctx->sigmask is inverted, + * so if the user is interested in a signal, that corresponding + * bit will be zero. + */ + if (sig < 0) { + if (ctx->tsk == tsk) { + ctx->tsk = NULL; + list_del_init(&ctx->lnk); + wake_up(&ctx->wqh); + } + } else { + if (!sigismember(&ctx->sigmask, sig)) + wake_up(&ctx->wqh); + } + } +} + +static void signalfd_cleanup(struct signalfd_ctx *ctx) +{ + struct signalfd_lockctx lk; + + /* + * This is tricky. If the sighand is gone, we do not need to remove + * context from the list, the list itself won't be there anymore. + */ + if (signalfd_lock(ctx, &lk)) { + list_del(&ctx->lnk); + signalfd_unlock(&lk); + } + kfree(ctx); +} + +static int signalfd_release(struct inode *inode, struct file *file) +{ + signalfd_cleanup(file->private_data); + return 0; +} + +static unsigned int signalfd_poll(struct file *file, poll_table *wait) +{ + struct signalfd_ctx *ctx = file->private_data; + unsigned int events = 0; + struct signalfd_lockctx lk; + + poll_wait(file, &ctx->wqh, wait); + + /* + * Let the caller get a POLLIN in this case, ala socket recv() when + * the peer disconnects. + */ + if (signalfd_lock(ctx, &lk)) { + if (next_signal(&lk.tsk->pending, &ctx->sigmask) > 0 || + next_signal(&lk.tsk->signal->shared_pending, + &ctx->sigmask) > 0) + events |= POLLIN; + signalfd_unlock(&lk); + } else + events |= POLLIN; + + return events; +} + +/* + * Copied from copy_siginfo_to_user() in kernel/signal.c + */ +static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo, + siginfo_t const *kinfo) +{ + long err; + + BUILD_BUG_ON(sizeof(struct signalfd_siginfo) != 128); + + /* + * Unused memebers should be zero ... + */ + err = __clear_user(uinfo, sizeof(*uinfo)); + + /* + * If you change siginfo_t structure, please be sure + * this code is fixed accordingly. + */ + err |= __put_user(kinfo->si_signo, &uinfo->signo); + err |= __put_user(kinfo->si_errno, &uinfo->err); + err |= __put_user((short)kinfo->si_code, &uinfo->code); + switch (kinfo->si_code & __SI_MASK) { + case __SI_KILL: + err |= __put_user(kinfo->si_pid, &uinfo->pid); + err |= __put_user(kinfo->si_uid, &uinfo->uid); + break; + case __SI_TIMER: + err |= __put_user(kinfo->si_tid, &uinfo->tid); + err |= __put_user(kinfo->si_overrun, &uinfo->overrun); + err |= __put_user((long)kinfo->si_ptr, &uinfo->svptr); + break; + case __SI_POLL: + err |= __put_user(kinfo->si_band, &uinfo->band); + err |= __put_user(kinfo->si_fd, &uinfo->fd); + break; + case __SI_FAULT: + err |= __put_user((long)kinfo->si_addr, &uinfo->addr); +#ifdef __ARCH_SI_TRAPNO + err |= __put_user(kinfo->si_trapno, &uinfo->trapno); +#endif + break; + case __SI_CHLD: + err |= __put_user(kinfo->si_pid, &uinfo->pid); + err |= __put_user(kinfo->si_uid, &uinfo->uid); + err |= __put_user(kinfo->si_status, &uinfo->status); + err |= __put_user(kinfo->si_utime, &uinfo->utime); + err |= __put_user(kinfo->si_stime, &uinfo->stime); + break; + case __SI_RT: /* This is not generated by the kernel as of now. */ + case __SI_MESGQ: /* But this is */ + err |= __put_user(kinfo->si_pid, &uinfo->pid); + err |= __put_user(kinfo->si_uid, &uinfo->uid); + err |= __put_user((long)kinfo->si_ptr, &uinfo->svptr); + break; + default: /* this is just in case for now ... */ + err |= __put_user(kinfo->si_pid, &uinfo->pid); + err |= __put_user(kinfo->si_uid, &uinfo->uid); + break; + } + + return err ? -EFAULT: sizeof(*uinfo); +} + +/* + * Returns either the size of a "struct signalfd_siginfo", or zero if the + * sighand we are attached to, has been orphaned. The "count" parameter + * must be at least the size of a "struct signalfd_siginfo". + */ +static ssize_t signalfd_read(struct file *file, char __user *buf, size_t count, + loff_t *ppos) +{ + struct signalfd_ctx *ctx = file->private_data; + ssize_t res = 0; + int locked, signo; + siginfo_t info; + struct signalfd_lockctx lk; + DECLARE_WAITQUEUE(wait, current); + + if (count < sizeof(struct signalfd_siginfo)) + return -EINVAL; + locked = signalfd_lock(ctx, &lk); + if (!locked) + return 0; + res = -EAGAIN; + signo = dequeue_signal(lk.tsk, &ctx->sigmask, &info); + if (signo == 0 && !(file->f_flags & O_NONBLOCK)) { + add_wait_queue(&ctx->wqh, &wait); + for (;;) { + set_current_state(TASK_INTERRUPTIBLE); + signo = dequeue_signal(lk.tsk, &ctx->sigmask, &info); + if (signo != 0) + break; + if (signal_pending(current)) { + res = -ERESTARTSYS; + break; + } + signalfd_unlock(&lk); + schedule(); + locked = signalfd_lock(ctx, &lk); + if (unlikely(!locked)) { + /* + * Let the caller read zero byte, ala socket + * recv() when the peer disconnect. This test + * must be done before doing a dequeue_signal(), + * because if the sighand has been orphaned, + * the dequeue_signal() call is going to crash. + */ + res = 0; + break; + } + } + remove_wait_queue(&ctx->wqh, &wait); + __set_current_state(TASK_RUNNING); + } + if (likely(locked)) + signalfd_unlock(&lk); + if (likely(signo)) + res = signalfd_copyinfo((struct signalfd_siginfo __user *) buf, + &info); + + return res; +} + +static const struct file_operations signalfd_fops = { + .release = signalfd_release, + .poll = signalfd_poll, + .read = signalfd_read, +}; + +/* + * Create a file descriptor that is associated with our signal + * state. We can pass it around to others if we want to, but + * it will always be _our_ signal state. + */ +asmlinkage long sys_signalfd(int ufd, sigset_t __user *user_mask, size_t sizemask) +{ + int error; + sigset_t sigmask; + struct signalfd_ctx *ctx; + struct sighand_struct *sighand; + struct file *file; + struct inode *inode; + struct signalfd_lockctx lk; + + if (sizemask != sizeof(sigset_t) || + copy_from_user(&sigmask, user_mask, sizeof(sigmask))) + return error = -EINVAL; + sigdelsetmask(&sigmask, sigmask(SIGKILL) | sigmask(SIGSTOP)); + signotset(&sigmask); + + if (ufd == -1) { + ctx = kmalloc(sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + init_waitqueue_head(&ctx->wqh); + ctx->sigmask = sigmask; + ctx->tsk = current; + + sighand = current->sighand; + /* + * Add this fd to the list of signal listeners. + */ + spin_lock_irq(&sighand->siglock); + list_add_tail(&ctx->lnk, &sighand->signalfd_list); + spin_unlock_irq(&sighand->siglock); + + /* + * When we call this, the initialization must be complete, since + * anon_inode_getfd() will install the fd. + */ + error = anon_inode_getfd(&ufd, &inode, &file, "[signalfd]", + &signalfd_fops, ctx); + if (error) + goto err_fdalloc; + } else { + file = fget(ufd); + if (!file) + return -EBADF; + ctx = file->private_data; + if (file->f_op != &signalfd_fops) { + fput(file); + return -EINVAL; + } + /* + * We need to be prepared of the fact that the sighand this fd + * is attached to, has been detched. In that case signalfd_lock() + * will return 0, and we'll just skip setting the new mask. + */ + if (signalfd_lock(ctx, &lk)) { + ctx->sigmask = sigmask; + signalfd_unlock(&lk); + } + wake_up(&ctx->wqh); + fput(file); + } + + return ufd; + +err_fdalloc: + signalfd_cleanup(ctx); + return error; +} + diff --git a/include/linux/Kbuild b/include/linux/Kbuild index 645b3b528150..bcd01f269f60 100644 --- a/include/linux/Kbuild +++ b/include/linux/Kbuild @@ -190,6 +190,7 @@ unifdef-y += errno.h unifdef-y += errqueue.h unifdef-y += ethtool.h unifdef-y += eventpoll.h +unifdef-y += signalfd.h unifdef-y += ext2_fs.h unifdef-y += ext3_fs.h unifdef-y += fb.h diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 66e2f0a70814..276ccaa2670c 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -84,6 +84,7 @@ extern struct nsproxy init_nsproxy; .count = ATOMIC_INIT(1), \ .action = { { { .sa_handler = NULL, } }, }, \ .siglock = __SPIN_LOCK_UNLOCKED(sighand.siglock), \ + .signalfd_list = LIST_HEAD_INIT(sighand.signalfd_list), \ } extern struct group_info init_groups; diff --git a/include/linux/sched.h b/include/linux/sched.h index 75f44379b7e9..97c0c7da58ef 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -391,6 +391,7 @@ struct sighand_struct { atomic_t count; struct k_sigaction action[_NSIG]; spinlock_t siglock; + struct list_head signalfd_list; }; struct pacct_struct { diff --git a/include/linux/signal.h b/include/linux/signal.h index 3fa0fab4a04b..9a5eac508e5e 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -233,6 +233,7 @@ static inline int valid_signal(unsigned long sig) return sig <= _NSIG ? 1 : 0; } +extern int next_signal(struct sigpending *pending, sigset_t *mask); extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p); extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *); extern long do_sigpending(void __user *, unsigned long); diff --git a/include/linux/signalfd.h b/include/linux/signalfd.h new file mode 100644 index 000000000000..510429495690 --- /dev/null +++ b/include/linux/signalfd.h @@ -0,0 +1,97 @@ +/* + * include/linux/signalfd.h + * + * Copyright (C) 2007 Davide Libenzi + * + */ + +#ifndef _LINUX_SIGNALFD_H +#define _LINUX_SIGNALFD_H + + +struct signalfd_siginfo { + __u32 signo; + __s32 err; + __s32 code; + __u32 pid; + __u32 uid; + __s32 fd; + __u32 tid; + __u32 band; + __u32 overrun; + __u32 trapno; + __s32 status; + __s32 svint; + __u64 svptr; + __u64 utime; + __u64 stime; + __u64 addr; + + /* + * Pad strcture to 128 bytes. Remember to update the + * pad size when you add new memebers. We use a fixed + * size structure to avoid compatibility problems with + * future versions, and we leave extra space for additional + * members. We use fixed size members because this strcture + * comes out of a read(2) and we really don't want to have + * a compat on read(2). + */ + __u8 __pad[48]; +}; + + +#ifdef __KERNEL__ + +#ifdef CONFIG_SIGNALFD + +/* + * Deliver the signal to listening signalfd. This must be called + * with the sighand lock held. Same are the following that end up + * calling signalfd_deliver(). + */ +void signalfd_deliver(struct task_struct *tsk, int sig); + +/* + * No need to fall inside signalfd_deliver() if no signal listeners + * are available. + */ +static inline void signalfd_notify(struct task_struct *tsk, int sig) +{ + if (unlikely(!list_empty(&tsk->sighand->signalfd_list))) + signalfd_deliver(tsk, sig); +} + +/* + * The signal -1 is used to notify the signalfd that the sighand + * is on its way to be detached. + */ +static inline void signalfd_detach_locked(struct task_struct *tsk) +{ + if (unlikely(!list_empty(&tsk->sighand->signalfd_list))) + signalfd_deliver(tsk, -1); +} + +static inline void signalfd_detach(struct task_struct *tsk) +{ + struct sighand_struct *sighand = tsk->sighand; + + if (unlikely(!list_empty(&sighand->signalfd_list))) { + spin_lock_irq(&sighand->siglock); + signalfd_deliver(tsk, -1); + spin_unlock_irq(&sighand->siglock); + } +} + +#else /* CONFIG_SIGNALFD */ + +#define signalfd_deliver(t, s) do { } while (0) +#define signalfd_notify(t, s) do { } while (0) +#define signalfd_detach_locked(t) do { } while (0) +#define signalfd_detach(t) do { } while (0) + +#endif /* CONFIG_SIGNALFD */ + +#endif /* __KERNEL__ */ + +#endif /* _LINUX_SIGNALFD_H */ + diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 3139f4412297..e049f14a75b7 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -604,6 +604,7 @@ asmlinkage long sys_get_robust_list(int pid, asmlinkage long sys_set_robust_list(struct robust_list_head __user *head, size_t len); asmlinkage long sys_getcpu(unsigned __user *cpu, unsigned __user *node, struct getcpu_cache __user *cache); +asmlinkage long sys_signalfd(int ufd, sigset_t __user *user_mask, size_t sizemask); int kernel_execve(const char *filename, char *const argv[], char *const envp[]); diff --git a/init/Kconfig b/init/Kconfig index a80bd8326bc6..db707204b751 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -492,6 +492,16 @@ config EPOLL Disabling this option will cause the kernel to be built without support for epoll family of system calls. +config SIGNALFD + bool "Enable signalfd() system call" if EMBEDDED + depends on ANON_INODES + default y + help + Enable the signalfd() system call that allows to receive signals + on a file descriptor. + + If unsure, say Y. + config SHMEM bool "Use full shmem filesystem" if EMBEDDED default y diff --git a/kernel/exit.c b/kernel/exit.c index e93691e9b325..c6d14b8008dd 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -83,6 +84,14 @@ static void __exit_signal(struct task_struct *tsk) sighand = rcu_dereference(tsk->sighand); spin_lock(&sighand->siglock); + /* + * Notify that this sighand has been detached. This must + * be called with the tsk->sighand lock held. Also, this + * access tsk->sighand internally, so it must be called + * before tsk->sighand is reset. + */ + signalfd_detach_locked(tsk); + posix_cpu_timers_exit(tsk); if (atomic_dec_and_test(&sig->count)) posix_cpu_timers_exit_group(tsk); diff --git a/kernel/fork.c b/kernel/fork.c index 083bf8953ce8..49530e40ea8b 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1422,12 +1422,15 @@ long do_fork(unsigned long clone_flags, #define ARCH_MIN_MMSTRUCT_ALIGN 0 #endif -static void sighand_ctor(void *data, struct kmem_cache *cachep, unsigned long flags) +static void sighand_ctor(void *data, struct kmem_cache *cachep, + unsigned long flags) { struct sighand_struct *sighand = data; - if (flags & SLAB_CTOR_CONSTRUCTOR) + if (flags & SLAB_CTOR_CONSTRUCTOR) { spin_lock_init(&sighand->siglock); + INIT_LIST_HEAD(&sighand->signalfd_list); + } } void __init proc_caches_init(void) @@ -1453,7 +1456,6 @@ void __init proc_caches_init(void) SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL); } - /* * Check constraints on flags passed to the unshare system call and * force unsharing of additional process context as appropriate. diff --git a/kernel/signal.c b/kernel/signal.c index 2ac3a668d9dd..34b7d6abce8f 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -113,8 +114,7 @@ void recalc_sigpending(void) /* Given the mask, find the first available signal that should be serviced. */ -static int -next_signal(struct sigpending *pending, sigset_t *mask) +int next_signal(struct sigpending *pending, sigset_t *mask) { unsigned long i, *s, *m, x; int sig = 0; @@ -629,6 +629,12 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t, struct sigqueue * q = NULL; int ret = 0; + /* + * Deliver the signal to listening signalfds. This must be called + * with the sighand lock held. + */ + signalfd_notify(t, sig); + /* * fast-pathed signals for kernel-internal things like SIGSTOP * or SIGKILL. @@ -1280,6 +1286,11 @@ int send_sigqueue(int sig, struct sigqueue *q, struct task_struct *p) ret = 1; goto out; } + /* + * Deliver the signal to listening signalfds. This must be called + * with the sighand lock held. + */ + signalfd_notify(p, sig); list_add_tail(&q->list, &p->pending.list); sigaddset(&p->pending.signal, sig); @@ -1323,6 +1334,11 @@ send_group_sigqueue(int sig, struct sigqueue *q, struct task_struct *p) q->info.si_overrun++; goto out; } + /* + * Deliver the signal to listening signalfds. This must be called + * with the sighand lock held. + */ + signalfd_notify(p, sig); /* * Put this signal on the shared-pending queue. @@ -1983,6 +1999,8 @@ int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from) /* * If you change siginfo_t structure, please be sure * this code is fixed accordingly. + * Please remember to update the signalfd_copyinfo() function + * inside fs/signalfd.c too, in case siginfo_t changes. * It should never copy any pad contained in the structure * to avoid security leaks, but must copy the generic * 3 ints plus the relevant union member. diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index d7306d0f3dfc..807e9bb8fcdb 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -141,3 +141,6 @@ cond_syscall(compat_sys_migrate_pages); cond_syscall(sys_bdflush); cond_syscall(sys_ioprio_set); cond_syscall(sys_ioprio_get); + +/* New file descriptors */ +cond_syscall(sys_signalfd); -- cgit v1.2.3