[PATCH 8/9] KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures [try #5]

David Howells
2009-09-02T07:21:29Z

Implement TIF_NOTIFY_RESUME for most of those architectures in which isn't yet
available, and, whilst we're at it, have it call the appropriate tracehook.

After this patch, blackfin, m68k* and xtensa still lack support and need
alteration of assembly code to make it work.

Resume notification can then be used (by a later patch) to install a new
session keyring on the parent of a process.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-arch@vger.kernel.org
---

arch/alpha/include/asm/thread_info.h | 5 ++++-
arch/alpha/kernel/signal.c | 5 +++++
arch/arm/include/asm/thread_info.h | 3 +++
arch/arm/kernel/entry-common.S | 2 +-
arch/arm/kernel/signal.c | 5 +++++
arch/avr32/include/asm/thread_info.h | 6 +++++-
arch/avr32/kernel/entry-avr32b.S | 2 +-
arch/avr32/kernel/signal.c | 5 +++++
arch/cris/kernel/ptrace.c | 5 +++++
arch/h8300/include/asm/thread_info.h | 2 ++
arch/h8300/kernel/signal.c | 5 +++++
arch/m32r/include/asm/thread_info.h | 2 ++
arch/m32r/kernel/signal.c | 5 +++++
arch/mips/include/asm/thread_info.h | 2 ++
arch/mips/kernel/signal.c | 5 +++++
arch/parisc/include/asm/thread_info.h | 4 +++-
arch/parisc/kernel/entry.S | 2 +-
arch/parisc/kernel/signal.c | 5 +++++
18 files changed, 64 insertions(+), 6 deletions(-)

diff --git a/arch/alpha/include/asm/thread_info.h b/arch/alpha/include/asm/thread_info.h
index 60c83ab..5076a88 100644
--- a/arch/alpha/include/asm/thread_info.h
+++ b/arch/alpha/include/asm/thread_info.h
@@ -75,6 +75,7 @@ register struct thread_info *__current_thread_info __asm__("$8");
#define TIF_UAC_SIGBUS 7
#define TIF_MEMDIE 8
#define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */
+#define TIF_NOTIFY_RESUME 10 /* callback before returning to user */
#define TIF_FREEZE 16 /* is freezing for suspend */

#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
@@ -82,10 +83,12 @@ register struct thread_info *__current_thread_info __asm__("$8");
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
+#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
#define _TIF_FREEZE (1<<TIF_FREEZE)

/* Work to do on interrupt/exception return. */
-#define _TIF_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED)
+#define _TIF_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+ _TIF_NOTIFY_RESUME)

/* Work to do on any return to userspace. */
#define _TIF_ALLWORK_MASK (_TIF_WORK_MASK \
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
index df65eaa..04e17c1 100644
--- a/arch/alpha/kernel/signal.c
+++ b/arch/alpha/kernel/signal.c
@@ -683,4 +683,9 @@ do_notify_resume(struct pt_regs *regs, struct switch_stack *sw,
{
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
do_signal(regs, sw, r0, r19);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}
diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index 73394e5..d3a39b1 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -130,11 +130,13 @@ extern void vfp_sync_state(struct thread_info *thread);
* TIF_SYSCALL_TRACE - syscall trace active
* TIF_SIGPENDING - signal pending
* TIF_NEED_RESCHED - rescheduling necessary
+ * TIF_NOTIFY_RESUME - callback before returning to user
* TIF_USEDFPU - FPU was used by this task this quantum (SMP)
* TIF_POLLING_NRFLAG - true if poll_idle() is polling TIF_NEED_RESCHED
*/
#define TIF_SIGPENDING 0
#define TIF_NEED_RESCHED 1
+#define TIF_NOTIFY_RESUME 2 /* callback before returning to user */
#define TIF_SYSCALL_TRACE 8
#define TIF_POLLING_NRFLAG 16
#define TIF_USING_IWMMXT 17
@@ -143,6 +145,7 @@ extern void vfp_sync_state(struct thread_info *thread);

#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
+#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
#define _TIF_USING_IWMMXT (1 << TIF_USING_IWMMXT)
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 8c3de1a..7813ab7 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -51,7 +51,7 @@ fast_work_pending:
work_pending:
tst r1, #_TIF_NEED_RESCHED
bne work_resched
- tst r1, #_TIF_SIGPENDING
+ tst r1, #_TIF_SIGPENDING|_TIF_NOTIFY_RESUME
beq no_work_pending
mov r0, sp @ 'regs'
mov r2, why @ 'syscall'
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index f6bc5d4..6759f45 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -707,4 +707,9 @@ do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall)
{
if (thread_flags & _TIF_SIGPENDING)
do_signal(&current->blocked, regs, syscall);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}
diff --git a/arch/avr32/include/asm/thread_info.h b/arch/avr32/include/asm/thread_info.h
index fc42de5..fd0c5d7 100644
--- a/arch/avr32/include/asm/thread_info.h
+++ b/arch/avr32/include/asm/thread_info.h
@@ -84,6 +84,7 @@ static inline struct thread_info *current_thread_info(void)
#define TIF_MEMDIE 6
#define TIF_RESTORE_SIGMASK 7 /* restore signal mask in do_signal */
#define TIF_CPU_GOING_TO_SLEEP 8 /* CPU is entering sleep 0 mode */
+#define TIF_NOTIFY_RESUME 9 /* callback before returning to user */
#define TIF_FREEZE 29
#define TIF_DEBUG 30 /* debugging enabled */
#define TIF_USERSPACE 31 /* true if FS sets userspace */
@@ -96,6 +97,7 @@ static inline struct thread_info *current_thread_info(void)
#define _TIF_MEMDIE (1 << TIF_MEMDIE)
#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
#define _TIF_CPU_GOING_TO_SLEEP (1 << TIF_CPU_GOING_TO_SLEEP)
+#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_FREEZE (1 << TIF_FREEZE)

/* Note: The masks below must never span more than 16 bits! */
@@ -103,13 +105,15 @@ static inline struct thread_info *current_thread_info(void)
/* work to do on interrupt/exception return */
#define _TIF_WORK_MASK \
((1 << TIF_SIGPENDING) \
+ | _TIF_NOTIFY_RESUME \
| (1 << TIF_NEED_RESCHED) \
| (1 << TIF_POLLING_NRFLAG) \
| (1 << TIF_BREAKPOINT) \
| (1 << TIF_RESTORE_SIGMASK))

/* work to do on any return to userspace */
-#define _TIF_ALLWORK_MASK (_TIF_WORK_MASK | (1 << TIF_SYSCALL_TRACE))
+#define _TIF_ALLWORK_MASK (_TIF_WORK_MASK | (1 << TIF_SYSCALL_TRACE) | \
+ _TIF_NOTIFY_RESUME)
/* work to do on return from debug mode */
#define _TIF_DBGWORK_MASK (_TIF_WORK_MASK & ~(1 << TIF_BREAKPOINT))

diff --git a/arch/avr32/kernel/entry-avr32b.S b/arch/avr32/kernel/entry-avr32b.S
index 009a801..169268c 100644
--- a/arch/avr32/kernel/entry-avr32b.S
+++ b/arch/avr32/kernel/entry-avr32b.S
@@ -281,7 +281,7 @@ syscall_exit_work:
ld.w r1, r0[TI_flags]
rjmp 1b

-2: mov r2, _TIF_SIGPENDING | _TIF_RESTORE_SIGMASK
+2: mov r2, _TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NOTIFY_RESUME
tst r1, r2
breq 3f
unmask_interrupts
diff --git a/arch/avr32/kernel/signal.c b/arch/avr32/kernel/signal.c
index 2722756..62d242e 100644
--- a/arch/avr32/kernel/signal.c
+++ b/arch/avr32/kernel/signal.c
@@ -322,4 +322,9 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, struct thread_info *ti)

if (ti->flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
do_signal(regs, &current->blocked, syscall);
+
+ if (ti->flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}
diff --git a/arch/cris/kernel/ptrace.c b/arch/cris/kernel/ptrace.c
index b326023..4f06d7f 100644
--- a/arch/cris/kernel/ptrace.c
+++ b/arch/cris/kernel/ptrace.c
@@ -36,4 +36,9 @@ void do_notify_resume(int canrestart, struct pt_regs *regs,
/* deal with pending signal delivery */
if (thread_info_flags & _TIF_SIGPENDING)
do_signal(canrestart,regs);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}
diff --git a/arch/h8300/include/asm/thread_info.h b/arch/h8300/include/asm/thread_info.h
index 8bbc8b0..70e67e4 100644
--- a/arch/h8300/include/asm/thread_info.h
+++ b/arch/h8300/include/asm/thread_info.h
@@ -89,6 +89,7 @@ static inline struct thread_info *current_thread_info(void)
TIF_NEED_RESCHED */
#define TIF_MEMDIE 4
#define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */
+#define TIF_NOTIFY_RESUME 6 /* callback before returning to user */
#define TIF_FREEZE 16 /* is freezing for suspend */

/* as above, but as bit values */
@@ -97,6 +98,7 @@ static inline struct thread_info *current_thread_info(void)
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
+#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_FREEZE (1<<TIF_FREEZE)

#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c
index cf3472f..56b3ab7 100644
--- a/arch/h8300/kernel/signal.c
+++ b/arch/h8300/kernel/signal.c
@@ -552,4 +552,9 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
{
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
do_signal(regs, NULL);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}
diff --git a/arch/m32r/include/asm/thread_info.h b/arch/m32r/include/asm/thread_info.h
index 07bb5bd..7157815 100644
--- a/arch/m32r/include/asm/thread_info.h
+++ b/arch/m32r/include/asm/thread_info.h
@@ -149,6 +149,7 @@ static inline unsigned int get_thread_fault_code(void)
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
#define TIF_SINGLESTEP 3 /* restore singlestep on return to user mode */
#define TIF_IRET 4 /* return with iret */
+#define TIF_NOTIFY_RESUME 5 /* callback before returning to user */
#define TIF_RESTORE_SIGMASK 8 /* restore signal mask in do_signal() */
#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
@@ -160,6 +161,7 @@ static inline unsigned int get_thread_fault_code(void)
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
#define _TIF_IRET (1<<TIF_IRET)
+#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_USEDFPU (1<<TIF_USEDFPU)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
diff --git a/arch/m32r/kernel/signal.c b/arch/m32r/kernel/signal.c
index 1812454..3220258 100644
--- a/arch/m32r/kernel/signal.c
+++ b/arch/m32r/kernel/signal.c
@@ -408,5 +408,10 @@ void do_notify_resume(struct pt_regs *regs, sigset_t *oldset,
if (thread_info_flags & _TIF_SIGPENDING)
do_signal(regs,oldset);

+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
+
clear_thread_flag(TIF_IRET);
}
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index f9df720..01cc163 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -115,6 +115,7 @@ register struct thread_info *__current_thread_info __asm__("$28");
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
#define TIF_SYSCALL_AUDIT 3 /* syscall auditing active */
#define TIF_SECCOMP 4 /* secure computing */
+#define TIF_NOTIFY_RESUME 5 /* callback before returning to user */
#define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal() */
#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
@@ -139,6 +140,7 @@ register struct thread_info *__current_thread_info __asm__("$28");
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP (1<<TIF_SECCOMP)
+#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_USEDFPU (1<<TIF_USEDFPU)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 830c5ef..a3d1015 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -700,4 +700,9 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
/* deal with pending signal delivery */
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
do_signal(regs);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}
diff --git a/arch/parisc/include/asm/thread_info.h b/arch/parisc/include/asm/thread_info.h
index 4ce0edf..ac775a7 100644
--- a/arch/parisc/include/asm/thread_info.h
+++ b/arch/parisc/include/asm/thread_info.h
@@ -59,6 +59,7 @@ struct thread_info {
#define TIF_MEMDIE 5
#define TIF_RESTORE_SIGMASK 6 /* restore saved signal mask */
#define TIF_FREEZE 7 /* is freezing for suspend */
+#define TIF_NOTIFY_RESUME 8 /* callback before returning to user */

#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
@@ -67,8 +68,9 @@ struct thread_info {
#define _TIF_32BIT (1 << TIF_32BIT)
#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
#define _TIF_FREEZE (1 << TIF_FREEZE)
+#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)

-#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | \
+#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | \
_TIF_NEED_RESCHED | _TIF_RESTORE_SIGMASK)

#endif /* __KERNEL__ */
diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S
index e552e54..8c4712b 100644
--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -948,7 +948,7 @@ intr_check_sig:
/* As above */
mfctl %cr30,%r1
LDREG TI_FLAGS(%r1),%r19
- ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK), %r20
+ ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NOTIFY_RESUME), %r20
and,COND(<>) %r19, %r20, %r0
b,n intr_restore /* skip past if we've nothing to do */

diff --git a/arch/parisc/kernel/signal.c b/arch/parisc/kernel/signal.c
index f825442..b3bfc43 100644
--- a/arch/parisc/kernel/signal.c
+++ b/arch/parisc/kernel/signal.c
@@ -645,4 +645,9 @@ void do_notify_resume(struct pt_regs *regs, long in_syscall)
if (test_thread_flag(TIF_SIGPENDING) ||
test_thread_flag(TIF_RESTORE_SIGMASK))
do_signal(regs, in_syscall);
+
+ if (test_thread_flag(TIF_NOTIFY_RESUME)) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}