KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures [try #6]

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>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
cc: linux-arch@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>

diff --git a/arch/alpha/include/asm/thread_info.h b/arch/alpha/include/asm/thread_info.h
index 60c83ab..5076a88 100644 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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..13dec27 100644 (file)
--- 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_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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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);
+       }
 }