Merge branch 'linus' into perf/core

Conflicts:
	arch/sparc/kernel/perf_event.c

Merge reason: Resolve the conflict.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

15 files changed, 221 insertions, 116 deletions

diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 7109f5b1baa8..2300426e531a 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -138,6 +138,7 @@ static int do_signal_pending(sigset_t *oldset, struct pt_regs *regs)
                         ti->local_flags &= ~_TLF_RESTORE_SIGMASK;
                         sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
                 }
+                regs->trap = 0;
                 return 0;               /* no signals delivered */
         }
 
@@ -164,6 +165,7 @@ static int do_signal_pending(sigset_t *oldset, struct pt_regs *regs)
                 ret = handle_rt_signal64(signr, &ka, &info, oldset, regs);
         }
 
+        regs->trap = 0;
         if (ret) {
                 spin_lock_irq(&current->sighand->siglock);
                 sigorsets(&current->blocked, &current->blocked,
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 266610119f66..b96a3a010c26 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -511,6 +511,7 @@ static long restore_user_regs(struct pt_regs *regs,
         if (!sig)
                 save_r2 = (unsigned int)regs->gpr[2];
         err = restore_general_regs(regs, sr);
+        regs->trap = 0;
         err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
         if (!sig)
                 regs->gpr[2] = (unsigned long) save_r2;
@@ -884,7 +885,6 @@ int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
         regs->nip = (unsigned long) ka->sa.sa_handler;
         /* enter the signal handler in big-endian mode */
         regs->msr &= ~MSR_LE;
-        regs->trap = 0;
         return 1;
 
 badframe:
@@ -1228,7 +1228,6 @@ int handle_signal32(unsigned long sig, struct k_sigaction *ka,
         regs->nip = (unsigned long) ka->sa.sa_handler;
         /* enter the signal handler in big-endian mode */
         regs->msr &= ~MSR_LE;
-        regs->trap = 0;
 
         return 1;
 
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 2fe6fc64b614..27c4a4584f80 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -178,7 +178,7 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
         err |= __get_user(regs->xer, &sc->gp_regs[PT_XER]);
         err |= __get_user(regs->ccr, &sc->gp_regs[PT_CCR]);
         /* skip SOFTE */
-        err |= __get_user(regs->trap, &sc->gp_regs[PT_TRAP]);
+        regs->trap = 0;
         err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
         err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
         err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c
index f9a706759364..0d6deb55a2ae 100644
--- a/arch/sparc/kernel/perf_event.c
+++ b/arch/sparc/kernel/perf_event.c
@@ -1076,13 +1076,24 @@ static int sparc_pmu_event_init(struct perf_event *event)
                 break;
 
         case PERF_TYPE_RAW:
-                return -EOPNOTSUPP;
+                pmap = NULL;
+                break;
 
         default:
                 return -ENOENT;
 
         }
 
+        if (pmap) {
+                hwc->event_base = perf_event_encode(pmap);
+        } else {
+                /*
+                 * User gives us "(encoding << 16) | pic_mask" for
+                 * PERF_TYPE_RAW events.
+                 */
+                hwc->event_base = attr->config;
+        }
+
         /* We save the enable bits in the config_base.  */
         hwc->config_base = sparc_pmu->irq_bit;
         if (!attr->exclude_user)
@@ -1092,8 +1103,6 @@ static int sparc_pmu_event_init(struct perf_event *event)
         if (!attr->exclude_hv)
                 hwc->config_base |= sparc_pmu->hv_bit;
 
-        hwc->event_base = perf_event_encode(pmap);
-
         n = 0;
         if (event->group_leader != event) {
                 n = collect_events(event->group_leader,
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index ea22cd373c64..75fad425e249 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c
@@ -453,8 +453,66 @@ static int save_fpu_state32(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
         return err;
 }
 
-static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
-                          int signo, sigset_t *oldset)
+/* The I-cache flush instruction only works in the primary ASI, which
+ * right now is the nucleus, aka. kernel space.
+ *
+ * Therefore we have to kick the instructions out using the kernel
+ * side linear mapping of the physical address backing the user
+ * instructions.
+ */
+static void flush_signal_insns(unsigned long address)
+{
+        unsigned long pstate, paddr;
+        pte_t *ptep, pte;
+        pgd_t *pgdp;
+        pud_t *pudp;
+        pmd_t *pmdp;
+
+        /* Commit all stores of the instructions we are about to flush.  */
+        wmb();
+
+        /* Disable cross-call reception.  In this way even a very wide
+         * munmap() on another cpu can't tear down the page table
+         * hierarchy from underneath us, since that can't complete
+         * until the IPI tlb flush returns.
+         */
+
+        __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
+        __asm__ __volatile__("wrpr %0, %1, %%pstate"
+                                : : "r" (pstate), "i" (PSTATE_IE));
+
+        pgdp = pgd_offset(current->mm, address);
+        if (pgd_none(*pgdp))
+                goto out_irqs_on;
+        pudp = pud_offset(pgdp, address);
+        if (pud_none(*pudp))
+                goto out_irqs_on;
+        pmdp = pmd_offset(pudp, address);
+        if (pmd_none(*pmdp))
+                goto out_irqs_on;
+
+        ptep = pte_offset_map(pmdp, address);
+        pte = *ptep;
+        if (!pte_present(pte))
+                goto out_unmap;
+
+        paddr = (unsigned long) page_address(pte_page(pte));
+
+        __asm__ __volatile__("flush     %0 + %1"
+                             : /* no outputs */
+                             : "r" (paddr),
+                               "r" (address & (PAGE_SIZE - 1))
+                             : "memory");
+
+out_unmap:
+        pte_unmap(ptep);
+out_irqs_on:
+        __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
+
+}
+
+static int setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
+                         int signo, sigset_t *oldset)
 {
         struct signal_frame32 __user *sf;
         int sigframe_size;
@@ -547,13 +605,7 @@ static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
         if (ka->ka_restorer) {
                 regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
         } else {
-                /* Flush instruction space. */
                 unsigned long address = ((unsigned long)&(sf->insns[0]));
-                pgd_t *pgdp = pgd_offset(current->mm, address);
-                pud_t *pudp = pud_offset(pgdp, address);
-                pmd_t *pmdp = pmd_offset(pudp, address);
-                pte_t *ptep;
-                pte_t pte;
 
                 regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
         
@@ -562,34 +614,22 @@ static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
                 if (err)
                         goto sigsegv;
 
-                preempt_disable();
-                ptep = pte_offset_map(pmdp, address);
-                pte = *ptep;
-                if (pte_present(pte)) {
-                        unsigned long page = (unsigned long)
-                                page_address(pte_page(pte));
-
-                        wmb();
-                        __asm__ __volatile__("flush     %0 + %1"
-                                             : /* no outputs */
-                                             : "r" (page),
-                                               "r" (address & (PAGE_SIZE - 1))
-                                             : "memory");
-                }
-                pte_unmap(ptep);
-                preempt_enable();
+                flush_signal_insns(address);
         }
-        return;
+        return 0;
 
 sigill:
         do_exit(SIGILL);
+        return -EINVAL;
+
 sigsegv:
         force_sigsegv(signo, current);
+        return -EFAULT;
 }
 
-static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
-                             unsigned long signr, sigset_t *oldset,
-                             siginfo_t *info)
+static int setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
+                            unsigned long signr, sigset_t *oldset,
+                            siginfo_t *info)
 {
         struct rt_signal_frame32 __user *sf;
         int sigframe_size;
@@ -687,12 +727,7 @@ static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
         if (ka->ka_restorer)
                 regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
         else {
-                /* Flush instruction space. */
                 unsigned long address = ((unsigned long)&(sf->insns[0]));
-                pgd_t *pgdp = pgd_offset(current->mm, address);
-                pud_t *pudp = pud_offset(pgdp, address);
-                pmd_t *pmdp = pmd_offset(pudp, address);
-                pte_t *ptep;
 
                 regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
         
@@ -704,38 +739,32 @@ static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
                 if (err)
                         goto sigsegv;
 
-                preempt_disable();
-                ptep = pte_offset_map(pmdp, address);
-                if (pte_present(*ptep)) {
-                        unsigned long page = (unsigned long)
-                                page_address(pte_page(*ptep));
-
-                        wmb();
-                        __asm__ __volatile__("flush     %0 + %1"
-                                             : /* no outputs */
-                                             : "r" (page),
-                                               "r" (address & (PAGE_SIZE - 1))
-                                             : "memory");
-                }
-                pte_unmap(ptep);
-                preempt_enable();
+                flush_signal_insns(address);
         }
-        return;
+        return 0;
 
 sigill:
         do_exit(SIGILL);
+        return -EINVAL;
+
 sigsegv:
         force_sigsegv(signr, current);
+        return -EFAULT;
 }
 
-static inline void handle_signal32(unsigned long signr, struct k_sigaction *ka,
-                                   siginfo_t *info,
-                                   sigset_t *oldset, struct pt_regs *regs)
+static inline int handle_signal32(unsigned long signr, struct k_sigaction *ka,
+                                  siginfo_t *info,
+                                  sigset_t *oldset, struct pt_regs *regs)
 {
+        int err;
+
         if (ka->sa.sa_flags & SA_SIGINFO)
-                setup_rt_frame32(ka, regs, signr, oldset, info);
+                err = setup_rt_frame32(ka, regs, signr, oldset, info);
         else
-                setup_frame32(ka, regs, signr, oldset);
+                err = setup_frame32(ka, regs, signr, oldset);
+
+        if (err)
+                return err;
 
         spin_lock_irq(&current->sighand->siglock);
         sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
@@ -743,6 +772,10 @@ static inline void handle_signal32(unsigned long signr, struct k_sigaction *ka,
                 sigaddset(&current->blocked,signr);
         recalc_sigpending();
         spin_unlock_irq(&current->sighand->siglock);
+
+        tracehook_signal_handler(signr, info, ka, regs, 0);
+
+        return 0;
 }
 
 static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
@@ -789,16 +822,14 @@ void do_signal32(sigset_t *oldset, struct pt_regs * regs,
         if (signr > 0) {
                 if (restart_syscall)
                         syscall_restart32(orig_i0, regs, &ka.sa);
-                handle_signal32(signr, &ka, &info, oldset, regs);
-
-                /* A signal was successfully delivered; the saved
-                 * sigmask will have been stored in the signal frame,
-                 * and will be restored by sigreturn, so we can simply
-                 * clear the TS_RESTORE_SIGMASK flag.
-                 */
-                current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
-
-                tracehook_signal_handler(signr, &info, &ka, regs, 0);
+                if (handle_signal32(signr, &ka, &info, oldset, regs) == 0) {
+                        /* A signal was successfully delivered; the saved
+                         * sigmask will have been stored in the signal frame,
+                         * and will be restored by sigreturn, so we can simply
+                         * clear the TS_RESTORE_SIGMASK flag.
+                         */
+                        current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
+                }
                 return;
         }
         if (restart_syscall &&
@@ -809,12 +840,14 @@ void do_signal32(sigset_t *oldset, struct pt_regs * regs,
                 regs->u_regs[UREG_I0] = orig_i0;
                 regs->tpc -= 4;
                 regs->tnpc -= 4;
+                pt_regs_clear_syscall(regs);
         }
         if (restart_syscall &&
             regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
                 regs->u_regs[UREG_G1] = __NR_restart_syscall;
                 regs->tpc -= 4;
                 regs->tnpc -= 4;
+                pt_regs_clear_syscall(regs);
         }
 
         /* If there's no signal to deliver, we just put the saved sigmask
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 9882df92ba0a..5e5c5fd03783 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -315,8 +315,8 @@ save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
         return err;
 }
 
-static void setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
-                        int signo, sigset_t *oldset)
+static int setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
+                       int signo, sigset_t *oldset)
 {
         struct signal_frame __user *sf;
         int sigframe_size, err;
@@ -384,16 +384,19 @@ static void setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
                 /* Flush instruction space. */
                 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
         }
-        return;
+        return 0;
 
 sigill_and_return:
         do_exit(SIGILL);
+        return -EINVAL;
+
 sigsegv:
         force_sigsegv(signo, current);
+        return -EFAULT;
 }
 
-static void setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
-                           int signo, sigset_t *oldset, siginfo_t *info)
+static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
+                          int signo, sigset_t *oldset, siginfo_t *info)
 {
         struct rt_signal_frame __user *sf;
         int sigframe_size;
@@ -466,22 +469,30 @@ static void setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
                 /* Flush instruction space. */
                 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
         }
-        return;
+        return 0;
 
 sigill:
         do_exit(SIGILL);
+        return -EINVAL;
+
 sigsegv:
         force_sigsegv(signo, current);
+        return -EFAULT;
 }
 
-static inline void
+static inline int
 handle_signal(unsigned long signr, struct k_sigaction *ka,
               siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
 {
+        int err;
+
         if (ka->sa.sa_flags & SA_SIGINFO)
-                setup_rt_frame(ka, regs, signr, oldset, info);
+                err = setup_rt_frame(ka, regs, signr, oldset, info);
         else
-                setup_frame(ka, regs, signr, oldset);
+                err = setup_frame(ka, regs, signr, oldset);
+
+        if (err)
+                return err;
 
         spin_lock_irq(&current->sighand->siglock);
         sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
@@ -489,6 +500,10 @@ handle_signal(unsigned long signr, struct k_sigaction *ka,
                 sigaddset(&current->blocked, signr);
         recalc_sigpending();
         spin_unlock_irq(&current->sighand->siglock);
+
+        tracehook_signal_handler(signr, info, ka, regs, 0);
+
+        return 0;
 }
 
 static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
@@ -546,17 +561,15 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
         if (signr > 0) {
                 if (restart_syscall)
                         syscall_restart(orig_i0, regs, &ka.sa);
-                handle_signal(signr, &ka, &info, oldset, regs);
-
-                /* a signal was successfully delivered; the saved
-                 * sigmask will have been stored in the signal frame,
-                 * and will be restored by sigreturn, so we can simply
-                 * clear the TIF_RESTORE_SIGMASK flag.
-                 */
-                if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                        clear_thread_flag(TIF_RESTORE_SIGMASK);
-
-                tracehook_signal_handler(signr, &info, &ka, regs, 0);
+                if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
+                        /* a signal was successfully delivered; the saved
+                         * sigmask will have been stored in the signal frame,
+                         * and will be restored by sigreturn, so we can simply
+                         * clear the TIF_RESTORE_SIGMASK flag.
+                         */
+                        if (test_thread_flag(TIF_RESTORE_SIGMASK))
+                                clear_thread_flag(TIF_RESTORE_SIGMASK);
+                }
                 return;
         }
         if (restart_syscall &&
@@ -567,12 +580,14 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
                 regs->u_regs[UREG_I0] = orig_i0;
                 regs->pc -= 4;
                 regs->npc -= 4;
+                pt_regs_clear_syscall(regs);
         }
         if (restart_syscall &&
             regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
                 regs->u_regs[UREG_G1] = __NR_restart_syscall;
                 regs->pc -= 4;
                 regs->npc -= 4;
+                pt_regs_clear_syscall(regs);
         }
 
         /* if there's no signal to deliver, we just put the saved sigmask
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
index 9fa48c30037e..006fe4515886 100644
--- a/arch/sparc/kernel/signal_64.c
+++ b/arch/sparc/kernel/signal_64.c
@@ -409,7 +409,7 @@ static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *
         return (void __user *) sp;
 }
 
-static inline void
+static inline int
 setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
                int signo, sigset_t *oldset, siginfo_t *info)
 {
@@ -483,26 +483,37 @@ setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
         }
         /* 4. return to kernel instructions */
         regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
-        return;
+        return 0;
 
 sigill:
         do_exit(SIGILL);
+        return -EINVAL;
+
 sigsegv:
         force_sigsegv(signo, current);
+        return -EFAULT;
 }
 
-static inline void handle_signal(unsigned long signr, struct k_sigaction *ka,
-                                 siginfo_t *info,
-                                 sigset_t *oldset, struct pt_regs *regs)
+static inline int handle_signal(unsigned long signr, struct k_sigaction *ka,
+                                siginfo_t *info,
+                                sigset_t *oldset, struct pt_regs *regs)
 {
-        setup_rt_frame(ka, regs, signr, oldset,
-                       (ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
+        int err;
+
+        err = setup_rt_frame(ka, regs, signr, oldset,
+                             (ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
+        if (err)
+                return err;
         spin_lock_irq(&current->sighand->siglock);
         sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
         if (!(ka->sa.sa_flags & SA_NOMASK))
                 sigaddset(&current->blocked,signr);
         recalc_sigpending();
         spin_unlock_irq(&current->sighand->siglock);
+
+        tracehook_signal_handler(signr, info, ka, regs, 0);
+
+        return 0;
 }
 
 static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
@@ -571,16 +582,14 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
         if (signr > 0) {
                 if (restart_syscall)
                         syscall_restart(orig_i0, regs, &ka.sa);
-                handle_signal(signr, &ka, &info, oldset, regs);
-
-                /* A signal was successfully delivered; the saved
-                 * sigmask will have been stored in the signal frame,
-                 * and will be restored by sigreturn, so we can simply
-                 * clear the TS_RESTORE_SIGMASK flag.
-                 */
-                current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
-
-                tracehook_signal_handler(signr, &info, &ka, regs, 0);
+                if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
+                        /* A signal was successfully delivered; the saved
+                         * sigmask will have been stored in the signal frame,
+                         * and will be restored by sigreturn, so we can simply
+                         * clear the TS_RESTORE_SIGMASK flag.
+                         */
+                        current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
+                }
                 return;
         }
         if (restart_syscall &&
@@ -591,12 +600,14 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
                 regs->u_regs[UREG_I0] = orig_i0;
                 regs->tpc -= 4;
                 regs->tnpc -= 4;
+                pt_regs_clear_syscall(regs);
         }
         if (restart_syscall &&
             regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
                 regs->u_regs[UREG_G1] = __NR_restart_syscall;
                 regs->tpc -= 4;
                 regs->tnpc -= 4;
+                pt_regs_clear_syscall(regs);
         }
 
         /* If there's no signal to deliver, we just put the saved sigmask
diff --git a/block/blk-map.c b/block/blk-map.c
index c65d7593f7f1..ade0a08c9099 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -307,7 +307,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
                 return PTR_ERR(bio);
 
         if (rq_data_dir(rq) == WRITE)
-                bio->bi_rw |= (1 << REQ_WRITE);
+                bio->bi_rw |= REQ_WRITE;
 
         if (do_copy)
                 rq->cmd_flags |= REQ_COPY_USER;
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index f65c6f01c475..9eba291eb6fd 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1019,10 +1019,20 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
          */
         atomic_set(&cfqg->ref, 1);
 
-        /* Add group onto cgroup list */
-        sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
-        cfq_blkiocg_add_blkio_group(blkcg, &cfqg->blkg, (void *)cfqd,
+        /*
+         * Add group onto cgroup list. It might happen that bdi->dev is
+         * not initiliazed yet. Initialize this new group without major
+         * and minor info and this info will be filled in once a new thread
+         * comes for IO. See code above.
+         */
+        if (bdi->dev) {
+                sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
+                cfq_blkiocg_add_blkio_group(blkcg, &cfqg->blkg, (void *)cfqd,
                                         MKDEV(major, minor));
+        } else
+                cfq_blkiocg_add_blkio_group(blkcg, &cfqg->blkg, (void *)cfqd,
+                                        0);
+
         cfqg->weight = blkcg_get_weight(blkcg, cfqg->blkg.dev);
 
         /* Add group on cfqd list */
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 6124c2fd2d33..5e4fadcdece9 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -4792,7 +4792,7 @@ static int __devinit cciss_init_one(struct pci_dev *pdev,
 clean4:
         kfree(h->cmd_pool_bits);
         /* Free up sg elements */
-        for (k = 0; k < h->nr_cmds; k++)
+        for (k-- ; k >= 0; k--)
                 kfree(h->scatter_list[k]);
         kfree(h->scatter_list);
         cciss_free_sg_chain_blocks(h->cmd_sg_list, h->nr_cmds);
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index a398ecdbd758..1f528fad3516 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -788,10 +788,11 @@ static const struct file_operations zero_fops = {
 /*
  * capabilities for /dev/zero
  * - permits private mappings, "copies" are taken of the source of zeros
+ * - no writeback happens
  */
 static struct backing_dev_info zero_bdi = {
         .name           = "char/mem",
-        .capabilities   = BDI_CAP_MAP_COPY,
+        .capabilities   = BDI_CAP_MAP_COPY | BDI_CAP_NO_ACCT_AND_WRITEBACK,
 };
 
 static const struct file_operations full_fops = {
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 7674efb55378..b33c78586bfc 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -680,6 +680,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 
         if (r == 0)
                 r = num;
+
+        omap_i2c_wait_for_bb(dev);
 out:
         omap_i2c_idle(dev);
         return r;
diff --git a/fs/char_dev.c b/fs/char_dev.c
index f80a4f25123c..143d393881cb 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -40,7 +40,9 @@ struct backing_dev_info directly_mappable_cdev_bdi = {
 #endif
                 /* permit direct mmap, for read, write or exec */
                 BDI_CAP_MAP_DIRECT |
-                BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP),
+                BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP |
+                /* no writeback happens */
+                BDI_CAP_NO_ACCT_AND_WRITEBACK),
 };
 
 static struct kobj_map *cdev_map;
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 81e086d8aa57..5581122bd2c0 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -52,8 +52,6 @@ struct wb_writeback_work {
 #define CREATE_TRACE_POINTS
 #include <trace/events/writeback.h>
 
-#define inode_to_bdi(inode)     ((inode)->i_mapping->backing_dev_info)
-
 /*
  * We don't actually have pdflush, but this one is exported though /proc...
  */
@@ -71,6 +69,27 @@ int writeback_in_progress(struct backing_dev_info *bdi)
         return test_bit(BDI_writeback_running, &bdi->state);
 }
 
+static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
+{
+        struct super_block *sb = inode->i_sb;
+        struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info;
+
+        /*
+         * For inodes on standard filesystems, we use superblock's bdi. For
+         * inodes on virtual filesystems, we want to use inode mapping's bdi
+         * because they can possibly point to something useful (think about
+         * block_dev filesystem).
+         */
+        if (sb->s_bdi && sb->s_bdi != &noop_backing_dev_info) {
+                /* Some device inodes could play dirty tricks. Catch them... */
+                WARN(bdi != sb->s_bdi && bdi_cap_writeback_dirty(bdi),
+                        "Dirtiable inode bdi %s != sb bdi %s\n",
+                        bdi->name, sb->s_bdi->name);
+                return sb->s_bdi;
+        }
+        return bdi;
+}
+
 static void bdi_queue_work(struct backing_dev_info *bdi,
                 struct wb_writeback_work *work)
 {
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index c2bf86f470ed..65d420499a61 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -30,6 +30,7 @@ EXPORT_SYMBOL_GPL(default_backing_dev_info);
 
 struct backing_dev_info noop_backing_dev_info = {
         .name           = "noop",
+        .capabilities   = BDI_CAP_NO_ACCT_AND_WRITEBACK,
 };
 EXPORT_SYMBOL_GPL(noop_backing_dev_info);
 
@@ -243,6 +244,7 @@ static int __init default_bdi_init(void)
         err = bdi_init(&default_backing_dev_info);
         if (!err)
                 bdi_register(&default_backing_dev_info, NULL, "default");
+        err = bdi_init(&noop_backing_dev_info);
 
         return err;
 }