From 84e07b9d0ac8728b1865b23498d746861a8ab4c2 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 20 Feb 2018 13:23:37 +1100 Subject: [PATCH] staging: lustre: improve API and implementation of blocking signals. According to comment for set_current_blocked() in kernel/signal.c, changing ->blocked directly is wrong. sigprocmask() should be called instead. So change cfs_block_sigsinv() and cfs_restore_sigs() to use sigprocmask(). For consistency, change them to pass the sigset_t by reference rather than by value. Also fix cfs_block_sigsinv() so that it correctly blocks signals above 32 on a 32bit host. Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman --- .../staging/lustre/include/linux/libcfs/libcfs.h | 4 ++-- .../staging/lustre/lnet/libcfs/linux/linux-prim.c | 24 +++++++--------------- drivers/staging/lustre/lustre/include/lustre_lib.h | 18 ++++++++-------- drivers/staging/lustre/lustre/llite/llite_mmap.c | 8 ++++---- 4 files changed, 22 insertions(+), 32 deletions(-) diff --git a/drivers/staging/lustre/include/linux/libcfs/libcfs.h b/drivers/staging/lustre/include/linux/libcfs/libcfs.h index 7f06b01..9dff050 100644 --- a/drivers/staging/lustre/include/linux/libcfs/libcfs.h +++ b/drivers/staging/lustre/include/linux/libcfs/libcfs.h @@ -67,8 +67,8 @@ /* * Defined by platform */ -sigset_t cfs_block_sigsinv(unsigned long sigs); -void cfs_restore_sigs(sigset_t sigset); +void cfs_block_sigsinv(unsigned long sigs, sigset_t *sigset); +void cfs_restore_sigs(sigset_t *sigset); struct libcfs_ioctl_handler { struct list_head item; diff --git a/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c b/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c index 6b73b98..0766659 100644 --- a/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c +++ b/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c @@ -44,29 +44,19 @@ #endif /* Block all signals except for the @sigs */ -sigset_t cfs_block_sigsinv(unsigned long sigs) +void cfs_block_sigsinv(unsigned long sigs, sigset_t *old) { - unsigned long flags; - sigset_t old; + sigset_t new; - spin_lock_irqsave(¤t->sighand->siglock, flags); - old = current->blocked; - sigaddsetmask(¤t->blocked, ~sigs); - recalc_sigpending(); - spin_unlock_irqrestore(¤t->sighand->siglock, flags); - - return old; + siginitsetinv(&new, sigs); + sigorsets(&new, ¤t->blocked, &new); + sigprocmask(SIG_BLOCK, &new, old); } EXPORT_SYMBOL(cfs_block_sigsinv); void -cfs_restore_sigs(sigset_t old) +cfs_restore_sigs(sigset_t *old) { - unsigned long flags; - - spin_lock_irqsave(¤t->sighand->siglock, flags); - current->blocked = old; - recalc_sigpending(); - spin_unlock_irqrestore(¤t->sighand->siglock, flags); + sigprocmask(SIG_SETMASK, old, NULL); } EXPORT_SYMBOL(cfs_restore_sigs); diff --git a/drivers/staging/lustre/lustre/include/lustre_lib.h b/drivers/staging/lustre/lustre/include/lustre_lib.h index 1efd86f..0053eaf 100644 --- a/drivers/staging/lustre/lustre/include/lustre_lib.h +++ b/drivers/staging/lustre/lustre/include/lustre_lib.h @@ -94,31 +94,31 @@ static inline int l_fatal_signal_pending(struct task_struct *p) */ #define l_wait_event_abortable(wq, condition) \ ({ \ - sigset_t __blocked; \ + sigset_t __old_blocked; \ int __ret = 0; \ - __blocked = cfs_block_sigsinv(LUSTRE_FATAL_SIGS); \ + cfs_block_sigsinv(LUSTRE_FATAL_SIGS, &__old_blocked); \ __ret = wait_event_interruptible(wq, condition); \ - cfs_restore_sigs(__blocked); \ + cfs_restore_sigs(&__old_blocked); \ __ret; \ }) #define l_wait_event_abortable_timeout(wq, condition, timeout) \ ({ \ - sigset_t __blocked; \ + sigset_t __old_blocked; \ int __ret = 0; \ - __blocked = cfs_block_sigsinv(LUSTRE_FATAL_SIGS); \ + cfs_block_sigsinv(LUSTRE_FATAL_SIGS, &__old_blocked); \ __ret = wait_event_interruptible_timeout(wq, condition, timeout);\ - cfs_restore_sigs(__blocked); \ + cfs_restore_sigs(&__old_blocked); \ __ret; \ }) #define l_wait_event_abortable_exclusive(wq, condition) \ ({ \ - sigset_t __blocked; \ + sigset_t __old_blocked; \ int __ret = 0; \ - __blocked = cfs_block_sigsinv(LUSTRE_FATAL_SIGS); \ + cfs_block_sigsinv(LUSTRE_FATAL_SIGS, &__old_blocked); \ __ret = wait_event_interruptible_exclusive(wq, condition); \ - cfs_restore_sigs(__blocked); \ + cfs_restore_sigs(&__old_blocked); \ __ret; \ }) #endif /* _LUSTRE_LIB_H */ diff --git a/drivers/staging/lustre/lustre/llite/llite_mmap.c b/drivers/staging/lustre/lustre/llite/llite_mmap.c index c0533bd..214b075 100644 --- a/drivers/staging/lustre/lustre/llite/llite_mmap.c +++ b/drivers/staging/lustre/lustre/llite/llite_mmap.c @@ -177,14 +177,14 @@ static int ll_page_mkwrite0(struct vm_area_struct *vma, struct page *vmpage, vio->u.fault.ft_vma = vma; vio->u.fault.ft_vmpage = vmpage; - set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM)); + cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM), &set); inode = vvp_object_inode(io->ci_obj); lli = ll_i2info(inode); result = cl_io_loop(env, io); - cfs_restore_sigs(set); + cfs_restore_sigs(&set); if (result == 0) { struct inode *inode = file_inode(vma->vm_file); @@ -334,7 +334,7 @@ static int ll_fault(struct vm_fault *vmf) * so that it can be killed by admin but not cause segfault by * other signals. */ - set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM)); + cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM), &set); restart: result = ll_fault0(vmf->vma, vmf); @@ -360,7 +360,7 @@ restart: result = VM_FAULT_LOCKED; } - cfs_restore_sigs(set); + cfs_restore_sigs(&set); return result; } -- 2.7.4