x86: mm: move mmap_sem unlock from mm_fault_error() to caller

This replaces four copies in various stages of mm_fault_error() handling
with just a single one.  It will also allow for more natural placement
of the unlocking after some further cleanup.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2014-12-15 14:46:06 -08:00
parent 67e2c38838
commit 7fb08eca45

View File

@ -844,11 +844,8 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
unsigned int fault)
{
struct task_struct *tsk = current;
struct mm_struct *mm = tsk->mm;
int code = BUS_ADRERR;
up_read(&mm->mmap_sem);
/* Kernel mode? Handle exceptions or die: */
if (!(error_code & PF_USER)) {
no_context(regs, error_code, address, SIGBUS, BUS_ADRERR);
@ -879,7 +876,6 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
unsigned long address, unsigned int fault)
{
if (fatal_signal_pending(current) && !(error_code & PF_USER)) {
up_read(&current->mm->mmap_sem);
no_context(regs, error_code, address, 0, 0);
return;
}
@ -887,14 +883,11 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
if (fault & VM_FAULT_OOM) {
/* Kernel mode? Handle exceptions or die: */
if (!(error_code & PF_USER)) {
up_read(&current->mm->mmap_sem);
no_context(regs, error_code, address,
SIGSEGV, SEGV_MAPERR);
return;
}
up_read(&current->mm->mmap_sem);
/*
* We ran out of memory, call the OOM killer, and return the
* userspace (which will retry the fault, or kill us if we got
@ -1247,6 +1240,7 @@ good_area:
return;
if (unlikely(fault & VM_FAULT_ERROR)) {
up_read(&mm->mmap_sem);
mm_fault_error(regs, error_code, address, fault);
return;
}